USVI Public Records

Document text (beginning — full text at the TXT link above)

Water Resources Data Puerto Rico and the U.S. Virgin Islands Water Year 1992 St Thomas I Islade V Culebra Isla de Vieques PUERTO RICO St John I U. S. V I R G I N ISLANDS Saint Croix I U.S. GEOLOGICAL SURVEY WATER-DATA REPORT PR-92-1 Prepared in cooperation with the Commonwealth of Puerto Rico, the Government of the U.S. Virgin Islands and other agencies CALENDAR FOR WATER YEAR 1992 1991 OCTOBER NOVEMBER DECEMBER S M T W T F S M T W S M T W T F S 12345 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 1 2 3456789 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 1234567 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 1992 JANUARY FEBRUARY MARCH M W S M T W T F S M T W 1234 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 1 2345678 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 1234567 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 APRIL MAY JUNE M W M W M W 234 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 JULY S M T W T F S 1 2 3456789 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 AUGUST S M T W T F S 123456 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 SEPTEMBER S M T W T F S 1234 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 1 2345678 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 12345 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 Water Resources Data Puerto Rico and the U.S. Virgin Islands Water Year 1992 by P.L. Dfaz, Z. Aquino, C. Figueroa-Alamo, R.J. Vachier, and A.V. Sanchez St Thomas I Isla de Vs* Culebra Isla de Vieques PUERTO RICO St John U. S. V I R G I IS ISLANDS Saint Croix I U.S. GEOLOGICAL SURVEY WATER-DATA REPORT PR-92-1 Prepared in cooperation with the Commonwealth of Puerto Rico, the Government of the U.S. Virgin Islands and other agencies U.S. DEPARTMENT OF THE INTERIOR BRUCE BABBITT, Secretary U.S. GEOLOGICAL SURVEY Dallas L. Peck, Director For additional information on the water resources investigation programs in Puerto Rico and the U.S. Virgin Islands write to: Chief, Caribbean District, Water Resources Division U.S. Geological Survey P.O. Box 364424 San Juan, Puerto Rico 00936-4424 (Telephone: (809) 749-4346) 1993 PREFACE This annual hydrologic data report of Puerto Rico and the U.S. Virgin Islands is one of a series of annual reports that document hydrologic data gathered from the U.S. Geological Survey's surface- and ground-water data-collection networks in each state, Puerto Rico, the U.S. Virgin Islands, and the other Trust Territories. These records of streamflow, ground-water levels, and quality of water provide the hydrologic information needed by state, local and Federal agencies, and the private sector for developing and managing our Nation's land and water resources. The report is the culmination of a concerted effort by dedicated personnel of the U.S. Geological Survey, Water Resources Division who collected, compiled, analyzed, verified, and organized the data, and who typed, edited, and assembled the report. In addition to the authors, who had primary responsibility for assuring that the information contained herein is accurate, complete and adheres to Geological Survey policy and established guidelines, the following personnel contributed significantly to the collection, processing and tabulations of the data: Jose M. Agis Carlos Narvaez George Arroyo Jerry A. Ortiz Angel Class-Cacho Keith Overton Iris M. Concepcion Antonio Pagan-Gavino Felix V. Elias David Peyton Angel G. Ferrer Rafael Pefia-Cortez Eduardo Figueroa Francisco Perez-Blair Pedro Galindo Carlos C. Rodriguez Jose Gonzalez Julio A. Rodriguez Evelyn S. Guevara Miguel Rodriguez Senen Guzman-Rios Jose Rene Sanchez Alien Heaken Luis Santiago-Rivera Felipe Hernandez Carlos Santos Richard Kessler Luis Soler Sandra Lagares Heriberto Torres-Sierra Xevier Maldonado Jose A. Torres Ernesto Mangual Ahmed Valencia Ruth I. Guzman typed the text of the report. Rafael Medina prepared the illustrations. This report was prepared in cooperation with agencies of the Commonwealth of Puerto Rico, the Government of the U.S. Virgin Islands, and with other federal agencies under the general supervision of Alien L. Zack, District Chief, Caribbean District, San Juan, Puerto Rico. 30277-1Q1 ____________ REPORT DOCUMENTATION PAGE 1. REPORT NO. USGS/WRD/HD-93/269 4. Title and Subtitle Water Resources Data for Puerto Rico and the U.S. Virgin Islands Water Year 1993 <.») Pedro L. Diaz, Z,aida Aquino, Calrlos Figueroa-Alamo, Ricardo J. Vachier, Ana V. Sanchez 5. Recipient** Accession No. S. Report D»te April 5, 1993 &. Pci-'orminf Oif enuetton Rept. No. USGS-WDR-PR-92-1 9. Performing Organisation N*m« »,-id Address U.S. Geological Survey, Water Resources Division P.O. Box 364424 San Juan, Puerto Rico 00936-4424 10. Pn|*ct/T*Ik/Wort Unit No. 11. Contr*ct(C) or Gr*nt(G) No. (0 (C) 12. Sponsoring Organization Name and Addr»*« U.S. Geological Survey, Water Resources Division P.O. Box 364424 San Juan, Puerto Rico 00936-4424 IX. Typ« of Report 4 Pvnod Cov«r«d Annual-Oct. 1, 1991 n Sppt ^0 1QQ7 .________ 14. IS. So :i«m*nt<ry Note* Prepared in cooperation with the Commonwealth of Puerto Rico, the Government of the U.S. Virgin Islands and other agencies. 16. Abstract (Limit: 200 words) Water resources data for surface-water, quality-of-water, and ground-water records for the 1992 water year for Puerto Rico and the U.S. Virgin Islands, consists of records of discharge, water quality of streams, and water levels of wells. This report contains discharge records for 74 stream flow-gaging stations; daily sediment records for 21 streamflow stations; 112 partial-record or miscellaneous streamflow stations; stage records for 9 reservoirs; water-quality records for 16 streamflow-gaging stations, 42 ungaged streamsites, 11 lake sites, 2 lagoons, and 1 bay; and water-level records for 91 observation wells. These data represent that part of the National Water Data System collected by the U.S. Geological Survey and cooperating local and federal agencies in Puerto Rico and the U.S. Virgin Islands. 17. Document Analysis a. Descriptors ^Surface water, *Water quality, *Ground water. Aquifers, Chemical analysis. Gaging stations, Hydrologic data. Sediments, Streamflow, Water analysis. Water Levels, Lakes. b. Id*ntlfi«rs/Op*n-Cnd*d Terms Puerto Rico, U.S. Virgin Islands, Sampling sites. c. COSATI Held/Group IS. Avail»bihty Sl»!«m«n. NO RESTRICTION ON DISTRIBUTIONS 19. Security Class CThis Report) ____Unclassified_____ 20. Security Class (This P»g«) 21. No. of Piges (S«« ANSI-Z39.1B) &e« 'nttructions on Pr-t OPTIONAL FORM 272 <*-77) <Form«rty NTlS-35) Dep*rtm*nt of Commerce CONTENTS y Page Preface .............................................................................. iii List of surface-water and water-quality stations, in downstream order, for which records are published in this volume ........................................ vii List of ground-water wells, by basin, for which records are published in this volume ............................................................. xii List of discontinued surface-water discharge or stage-only stations .................................... xv Introduction .......................................................................... 1 Cooperation .......................................................................... 2 Summary of hydrologic conditions ........................................................... 3 Precipitation ...................................................................... 3 Surface water ..................................................................... 3 Ground water ..................................................................... 5 Water quality ..................................................................... 5 Special networks and programs ............................................................. 9 Explanation of records ................................................................... 9 Station identification numbers .......................................................... 9 Downstream order system ......................................................... 9 Latitude-longitude system ......................................................... 9 Records of stage and water discharge ..................................................... 19 Data collection and computation .................................................... 19 Data presentation ............................................................... 20 Station manuscript .......................................................... 20 Data table of daily mean values ................................................. 21 Statistics of monthly mean data ................................................. 22 Summary statistics .......................................................... 22 Identifying estimated daily discharge ................................................. 23 Accuracy of the records .......................................................... 23 Records of surface-water quality ........................................................ 24 Classification of records .......................................................... 24 Arrangement of records .......................................................... 24 On-site measurements and sample collection ............................................ 24 Water temperature .............................................................. 25 Sediment .................................................................... 25 Laboratory measurements ......................................................... 25 Data presentation ............................................................... 26 Remark codes ................................................................. 27 Records of ground-water levels ......................................................... 27 Data collection and computation .................................................... 27 Data presentation ............................................................... 28 Records of ground-water quality ........................................................ 28 Data collection and computation .................................................... 29 Data presentation ............................................................... 29 Access to WATSTORE data ............................................................... 29 Definition of terms ...................................................................... 30 Publications on Techniques of Water-Resources Investigations ....................................... 40 Surface- and quality-of-water records for Puerto Rico ............................................. 43 Discharge at partial-record stations in Puerto Rico ............................................... 455 Water-quality at partial-record stations in Puerto Rico ............................................ 469 Ground-water records for Puerto Rico ....................................................... 481 Surface-water records for the U.S. Virgin Islands ............................................... 537 Ground-water records for the U.S. Virgin Islands ............................................... 555 Index .............................................................................. 593 VI ILLUSTRATIONS Page Figure 1. Graph showing monthly-mean discharge of selected streams in Puerto Rico ...................... 4 2. Graph showing ground-water levels at selected wells in Puerto Rico and the U.S. Virgin Islands ............................................................... 7 3. Map showing location of fecal coliform bacteria concentration at sampled sites .................. 10 4. Map showing location of fecal streptococci bacteria concentration at sampled sites ................ 11 5. Map showing location of surface-water stations in Puerto Rico .............................. 12 6. Map showing location of water-quality stations in Puerto Rico .............................. 13 7. Map showing location of low-flow partial-record stations in Southwest Puerto Rico ............... 14 8. Map showing location of ground-water stations in Puerto Rico .............................. 15 9. Map showing location of surface-water stations in U.S. Virgin Islands ........................ 16 10. Map showing location of ground-water stations in the U.S. Virgin Islands ..................... 17 11. Map showing location of surface-water stations in Vieques and Culebra Islands ................. 18 12. Grid showing system for numbering wells and miscellaneous site (latitude and longitude) .......... 19 13. Map showing the Rio Guajataca basin .............................................. 45 14. Map showing the Rio Camuy basin ................................................ 53 15. Map showing the Rio Grande de Arecibo basin ........................................ 59 16. Map showing the Rio Grande de Manati basin ......................................... 85 17. Map showing the Rio Cibuco basin ............................................... 107 18. Map showing the Rio de la Plata basin ............................................. 115 19. Map showing the Rio Hondo to the Rio Puerto Nuevo basins ............................. 163 20. Map showing the Rio Grande de Loiza basin ......................................... 207 21. Map showing northeastern river basins the Rio Herrera to the Rio Antdn Ruiz basins ............ 343 22. Map showing southeastern river basins the Rio Humacao to the Rio Seco basins ................ 365 23. Map showing south coast river basins the Rio Salinas to the Rio Jacaguas basins ............... 381 24. Map showing south coast river basins the Rio Inabon to the Rio Loco basins .................. 395 25. Map showing the Rio Guanajibo basin ............................................. 413 26. Map showing the Rio Yagiiez and the Rio Grande de Anasco basins ........................ 429 27. Map showing the Rio Culebrinas basin ............................................. 441 TABLES Page Table 1. Island-wide monthly precipitation and annual averages for 1992 water year and the 30-year reference period, 1951-80 .............................................. 3 2. Peak discharges during January 5-6, 1992 and maximums previously recorded at selected streamflow gaging stations in Puerto Rico ................................... 5 3. Highest water level recorded during 1992 water year and previous high water level (in feet below land-surface datum) at selected ground-water wells in Puerto Rico and the U.S. Virgin Islands ............................................ 6 4. Surface-water quality stations in Puerto Rico with highest concentration of selected constituents during water year 1992 ......................................... 8 5. Factors for conversion of chemical constituents in milligrams per liter to milli- equivalents per liter .......................................................... 34 SURFACE-WATER AND WATER-QUALITY STATIONS, IN DOWNSTREAM ORDER, VII FOR WHICH RECORDS ARE PUBLISHED IN THIS VOLUME (Letter after station name designates type of data: (d) discharge, (c) chemical, (b) biological, (s) sediment, (p) pesticide, (e) elevation, gage heights) Station number RIO GUAJATACA BASIN Rio Guajataca at Lares (d,c,b) .......................................... 50010500 46 Canal Principal de Diversiones at Lago Guajataca (c,b) ........................ 50011000 49 Rio Guajataca above mouth near Quebradillas (c,b) ........................... 50011400 51 RIO CAMUY BASIN Rio Camuy at Tres Pueblos Sinkhole (d) ................................... 50014600 54 Rio Camuy near Bayaney (d) ........................................... 50014800 55 Rio Camuy near Hatillo (d) ............................................ 50015700 56 RIO GRANDE DE ARECIBO BASIN Rio Grande de Arecibo near Adjuntas (c,b) ................................. 50020500 60 Rio Grande de Arecibo near Utuado (c,b) .................................. 50025000 62 Rio Saliente at Coabey near Jayuya (d) ................................ 50025155 64 Rio Caonillas above Lago Caonillas near Jayuya (c,b) ............................. 50026050 65 Lago Caonillas at Caonillas (e) ...................................... 50026140 67 Rio Grande de Arecibo below Lago Dos Bocas near Florida (c,b) ................. 50027250 68 Rio Grande de Arecibo above Arecibo (d) .................................. 50027750 70 Rio Tanama near Utuado (d,c,b,s) .................................... 50028000 72 Rio Tanama at Charco Hondo (d) .................................... 50028400 81 Rio Grande de Arecibo at Central Cambalache (c,b) ........................... 50029000 82 RIO GRANDE DE MANATI BASIN Rio Orocovis at Orocovis (d) ........................................ 50030460 86 Rio Orocovis near Orocovis (c,b) ..................................... 50030700 89 Rio Grande de Manati near Morovis (d,c,b) ................................. 50031200 91 Lago El Guineo at Damsite (e) ...................................... 50032290 94 Lago Matrullas at Damsite (e) ....................................... 50032590 95 Rio Bauta near Orocovis (d) ........................................ 50034000 96 Rio Grande de Manati at Ciales (d) ....................................... 50035000 97 Rio Grande de Manati at Highway 149 at Ciales (c,b) .......................... 50035500 98 Rio Cialitos at Highway 649 at Ciales (c,b) ............................. 50035950 100 Rio Grande de Manati at Highway 2 near Manati (d,c,b,p) ...................... 50038100 102 LACUNA TORTUGUERO BASIN Laguna Tortuguero Outlet near Vega Baja (c,b) .............................. 50038200 106 RIO CIBUCO BASIN Rio Cibuco below Corozal (d,c,b) ........................................ 50038320 108 Rio Cibuco at Vega Baja (d,c,b) ......................................... 50039500 111 RIO DE LA PLATA BASIN Lago Carite at Gate Tower (e) .......................................... 50039990 116 Rio de La Plata at Proyecto La Plata (d,c,b) ................................. 50043000 117 Rio de La Plata at Comerio (d) .......................................... 50043800 120 Rio de La.Plata near Comerio (c,b) ....................................... 50044000 127 Rio Guadiana at Guadiana (d) ....................................... 50044830 129 Rio Guadiana near Naranjito (c,b) .................................... 50044850 141 Lago La Plata at Damsite (e) ........................................... 50045000 143 Rio de La Plata below La Plata Dam (d) ................................... 50045010 144 Rio de La Plata at Highway 2 near Toa Alta (d,c,b,s,p) ......................... 50046000 159 VIII SURFACE-WATER AND WATER-QUALITY STATIONS, IN DOWNSTREAM ORDER, FOR WHICH RECORDS ARE PUBLISHED IN THIS VOLUME-Continued Station number Page RIO HONDO BASIN Rio Hondo at Flood Channel near Catano (c,b) .............................. 50047530 164 RIO DE BAYAMON BASIN Lago de Cidra at Damsite near Cidra (e) ................................... 50047550 166 Rio de Bayamdn below Cidra Dam (d) .................................... 50047560 167 Rio de Bayamdn near Aguas Buenas (c,b) .................................. 50047600 178 Rio de Bayamdn near Bayamdn (d) ...................................... 50047850 180 Rio Guaynabo near Bayamdn (c,b) .................................... 50047990 182 Rio de Bayamdn at Flood Channel at Bayamdn (c,b,p) ......................... 50048510 183 RIO PUERTO NUEVO BASIN Rio Piedras: Rio Piedras at El Senorial (d,s) .......................................... 50048770 185 Rio Piedras near Rio Piedras (c,b,p) ...................................... 50048800 192 Rio Piedras at Rio Piedras (d,s) ......................................... 50049000 194 Rio Piedras at Hato Rey (d,c,b) ......................................... 50049100 201 Laguna San Jose: Laguna San Jose No 2 at San Juan (c,b) ................................... 50049820 204 Bah fa de San Juan: Bahia de San Juan No 5 at San Juan (c,b) .................................. 50049920 205 QUEBRADA BLASINA BASIN Quebrada Blasina near Carolina (c,b) ..................................... 50050300 208 RIO GRANDE DE LOIZA BASIN Rio Grande de Loiza at Quebrada Arenas (d) ................................ 50050900 210 Quebrada Blanca at El Jagual (d,s) .................................... 50051150 212 Quebrada Salvatierra near San Lorenzo (d,s) ............................. 50051180 219 Rio Cayaguas at Cerro Gordo (d) ..................................... 50051310 226 Rio Grande de Loiza at Highway 183 near San Lorenzo (d) ..................... 50051800 227 Rio Turabo above Borinquen (d) ..................................... 50053025 241 Rio Grande de Loiza at Caguas (d,c,b,s) ................................... 50055000 255 Rio Caguitas near Aguas Buenas (d) .................................. 50055100 264 Rio Caguitas at Villa Blanca at Caguas (d) .............................. 50055225 278 Rio Caguitas at Highway 30 at Caguas (c,b) ............................. 50055250 291 Rio Bairoa at Bairoa (d) ........................................... 50055390 292 Rio Bairoa near Caguas (c,b) ........................................ 50055400 296 Rio Gurabo: Rio Gurabo below El Mango (d) ..................................... 50055750 298 Rio Valenciano near Juncos (d) ................................... 50056400 306 Quebrada Mamey near Gurabo (d) ................................. 50056900 314 Rio Gurabo at Gurabo (d,s) ......................................... 50057000 316 Rio Gurabo near Gurabo (c,b) ....................................... 50057025 324 Rio Canas at Rio Canas (d,s) ........................................ 50058350 326 Lago Loiza at Damsite (c,b,e) .......................................... 50059000 334 Rio Grande de Loiza below Trujillo Alto (c,b) ............................... 50059100 336 Rio Grande de Loiza at Carolina (e) ...................................... 50061000 338 Rio Candvanas near Campo Rico (d) .................................. 50061800 340 SURFACE-WATER AND WATER-QUALITY STATIONS, IN DOWNSTREAM ORDER, IX FOR WHICH RECORDS ARE PUBLISHED IN THIS VOLUME-Continued Station number RIO ESPIRITU SANTO BASIN Quebrada Sonadora near El Verde (d) ................................. 50063440 344 Quebrada Toronja at El Verde (d) .................................... 50063500 346 Rio Espiritu Santo near Rio Grande (d,c,b) ................................. 50063800 348 Rio Grande near El Verde (d) ....................................... 50064200 351 RIO MAMEYES BASIN Rio Mameyes near Sabana (d) .......................................... 50065500 353 RIO SABANA BASIN Rio Sabana at Sabana (d) .............................................. 50067000 355 RIO FAJARDO BASIN Rio Fajardo near Fajardo (d,c,b,p) ........................................ 50071000 357 Rio Fajardo below Fajardo (c,b) ......................................... 50072500 360 RIO BLANCO BASIN Rio Icacos near Naguabo (d) ........................................... 50075000 362 RIO HUMACAO BASIN Rio Humacao at Las Piedras (d) ......................................... 50081000 366 Rio Humacao at Highway 3 at Humacao (c,b) ............................... 50082000 367 RIO GUAYANES BASIN Rio Guayanes at Yabucoa (c,b,p) ........................................ 50083500 369 Rio Guayanes above mouth at Playa de Guayanes (c,b) ......................... 50086500 371 RIO MAUNABO BASIN Rio Maunabo at Lizas (d) ............................................. 50090500 373 Rio Maunabo at Maunabo (c,b) ......................................... 50091000 374 RIO CfflCO BASIN Rio Chico at Providencia (c,b) .......................................... 50091800 376 RIO GRANDE DE PATILLAS BASIN Rio Grande de Patillas near Patillas (c,b) ................................... 50092000 378 RIO SALINAS BASIN Rio Lapas near Rabo del Buey (d) ....................................... 50100200 382 Rio Majada at La Plena (d) ............................................ 50100450 383 RIO COAMO BASIN Rio Coamo near Coamo (c,b) ........................................... 50106500 384 RIO DESCALABRADO BASIN Rio Descalabrado near Los Llanos (d) ..................................... 50108000 386 RIO JACAGUAS BASIN Rio Toa Vaca above Lago Toa Vaca (d,s) ............................... 50110900 387 Rio Jacaguas at Juana Diaz (d) .......................................... 50111500 394 RIO INABON BASIN Rio Inabon at Real Abajo (d) ........................................... 50112500 396 X SURFACE-WATER AND WATER-QUALITY STATIONS, IN DOWNSTREAM ORDER, FOR WHICH RECORDS ARE PUBLISHED IN THIS VOLUME-Continued Station number Page RIO BUCANA BASIN Rio Bucand: Rio Cerrillos above Lago Cerrillos near Ponce (d) ............................ 50113800 397 Rio Cerrillos near Ponce (d,c,b) ......................................... 50114000 398 Rio Bucan£ at Hwy 14 Bridge near Ponce (d) ............................... 50114390 401 RIO PORTUGUES BASIN Rio Portugues near Ponce (d,c,b) ........................................ 50115000 402 Rio Portugues at Ponce (c,b,p) .......................................... 50116200 405 RIO GUAYANILLA BASIN Rio Guayanilla near Guayanilla (d) ....................................... 50124200 407 Rio Guayanilla at Central Rufina (c,b,p) ................................... 50124700 408 RIO YAUCO BASIN Lago Luchetti at Damsite (e) ........................................... 50125780 410 RIO LOCO BASIN Rio Loco at Guanica (c,b,p) ............................................ 50129700 411 RIO GUANAJIBO BASIN Rio Guanajibo at Highway 119 at San German (d) ............................ 50131990 414 Rio Guanajibo near San German (c,b) ..................................... 50133600 415 Rio Rosario near Hormigueros (d,c,b,s) ................................ 50136400 417 Rio Guanajibo near Hormigueros (d,c,b,p) .................................. 50138000 426 RIO YAGUEZ BASIN Rio Yaguez near Mayaguez (c,b) ........................................ 50138800 430 RIO GRANDE DE ANASCO BASIN Lago Guayo near Castaner (e) ....................................... 50141500 432 Rio Grande de Anasco near Lares (c,b) .................................... 50143000 433 Rio Grande de Anasco near San Sebastian (d,c,b,s) ............................ 50144000 435 Rio Grande de Anasco near Anasco (c,b,p) ................................. 50146000 438 RIO CULEBRINAS BASIN Rio Culebrinas near San Sebastian (c,b) ................................... 50147600 442 Rio Culebrinas at Highway 404 near Moca (d) ............................... 50147800 444 Rio Culebrinas near Aguada (c,b,p) ....................................... 50149100 445 CULEBRA, P.R. Quebrada Resaca near Monte Resaca (e) ................................... 50214500 447 Drainage Canal at Culebra Airport (e) ..................................... 50215000 448 VIEQUES, P.R. Quebrada Cofresi Tributary near Isabela II (e) ............................... 50231000 449 Quebrada La Mina near Esperanza (e) ..................................... 50232000 451 Quebrada Pildn at Colonia Puerto Real (e) .................................. 50233000 453 ST THOMAS, US VIRGIN ISLANDS Bonne Resolution Gut at Bonne Resolution (d) .............................. 50252000 538 Turpentine Run at Mariendal (d) ......................................... 50276000 539 ST JOHN, US VIRGIN ISLANDS Guinea Gut at Bethany (d) ............................................. 50295000 540 Cruz Bay Gut at Cruz Bay (e) .......................................... 50295500 541 SURFACE-WATER AND WATER-QUALITY STATIONS, IN DOWNSTREAM ORDER, XI FOR WHICH RECORDS ARE PUBLISHED IN THIS VOLUME-Continued Station number Page ST CROIX, US VIRGIN ISLANDS River Gut at River (e) ................................................ 50332000 542 River Gut near Golden Grove (d) ........................................ 50333500 543 River Gut at Hwy 66 at Fairplanes (d) .................................... 50333700 544 Bethlehen Gut at Hwy 66 at Fairplanes (d) ................................. 50334500 547 Gut 4.5 at Cane Valley (e) ............................................. 50337500 550 Jolly Hill Gut at Jolly Hill (d) .......................................... 50345000 551 Salt River at Canaan (e) .............................................. 50348000 552 Gut 10 near Altona (e) ............................................... 50349000 553 Discharge at partial-record stations and miscellaneous sites .......................... 455 Low-flow partial-record stations .......................................... 456 Analyses of samples collected of water-quality partial-record stations and miscellaneous sites ....................................... 469 XII GROUND-WATER WELLS, BY BASIN, FOR WHICH RECORDS ARE PUBLISHED Page RIO GUAJATACA BASIN Well 182422067015100 Local number 165 ................................................. 482 Well 182647066552400 Local number 202 ................................................. 483 RIO GRANDE DE ARECIBO BASIN Well 182737066370900 Local number 204 ................................................. 484 RIO GRANDE DE MANATI BASIN Well 182757066325600 Local number 206 ................................................. 485 Well 182710066303700 Local number 207 ................................................. 486 Well 182308066260400 Local number 210 ................................................. 487 RIO CIBUCO BASIN Well 182647066201700 Local number 70 .................................................. 488 Well 182615066235300 Local number 211 ................................................. 489 Well 182515066194000 Local number 212 ................................................. 490 Well 182330066185700 Local number 213 ................................................. 491 RIO DE LA PLATA BASIN Well 182746066170800 Local number 214 ................................................. 492 Well 182530066135400 Local number 216 ................................................. 493 Well 182655066142400 Local number 217 ................................................. 494 RIO HONDO TO RIO PUERTO NUEVO BASINS Well 182623066111000 Local number 218 ................................................. 495 Well 182441066082600 Local number 219 ................................................. 496 Well 182413066044000 Local number 220 ................................................. 497 Well 182511066045401 Local number PN-2 ................................................ 498 Well 182435066052701 Local number PN-5 .................................................... 499 Well 182445066043401 Local number PN-6 ................................................ 500 Well 182437066040501 Local number PN-7 .................................................... 501 Well 182443066041502 Local number PN-8c ............................................... 502 Well 182417066042700 Local number PN-10 ............................................... 503 Well 182349066032600 Local number PN-13 ............................................... 504 Well 182406066034700 Local number PN-19 ............................................... 505 RIO GRANDE DE LOIZA BASIN Well 181550065593201 Local number 50 .................................................. 506 Well 182515065594100 Local number 222 ................................................. 507 Well 181513065554601 Local number CJ-TW-3B ............................................ 508 Well 181352066025300 Local number CJ-TW-19A ........................................... 509 RIO HUMACAO TO RIO SECO BASINS Well 175858066100200 Local number 6 ................................................... 510 Well 180415065513900 Local number 96 .................................................. 511 GROUND-WATER WELLS, BY BASIN, FOR WHICH RECORDS ARE PUBLISHED-Continued XIII Page RIO SALINAS TO RIO JACAGUAS BASINS Well 175829066232200 Local number 87 .................................................. 512 Well 180002066132200 Local number HW-TW-01 ........................................... 513 Well 180001066122002 Local number HW-TW-03C .......................................... 514 Well 175947066130601 Local number HW-TW-05B .......................................... 515 Well 175957066123400 Local number HW-TW-13 ........................................... 516 Well 175946066102000 Local number HW-TW-14 ........................................... 517 Well 180206066135500 Local number RM-05 ............................................... 518 Well 180104066152300 Local number RM-10 ............................................... 519 RIO INABON TO RIO LOCO BASINS Well 180133066503300 Local number 132 ................................................. 520 Well 175900066354200 Local number 141 ................................................. 521 RIO GUANAJIBO BASIN Well 180132067033800 Local number 143 ................................................. 522 Well 180627067080600 Local number CR-TW-1 ............................................. 523 Well 180628067075800 Local number CR-TW-2A ............................................ 524 Well 180628067075801 Local number CR-TW-2B ............................................ 525 Well 180628067075802 Local number CR-TW-2C ............................................ 526 Well 180643067080400 Local number CR-TW-3 ............................................. 527 Well 180650067073700 Local number CR-TW-4 ............................................. 528 Well 180557067083100 Local number CR-TW-5 ............................................. 529 Well 180617067083300 Local number CR-TW-6 ............................................. 530 Well 180604067085100 Local number CR-TW-7 ............................................. 531 Well 180547067084800 Local number CR-TW-8 ............................................. 532 Well 180628067084300 Local number CR-TW-9A ............................................ 533 Well 180547067073100 Local number CR-TW-10 ............................................ 534 RIO CULEBRINAS BASIN Well 182442067091700 Local number 200 ................................................. 535 ST. CROK, U.S. VIRGIN ISLANDS Well 174225064471900 Local number 1 ................................................... 556 Well 174225064472000 Local number 2 ................................................... 557 Well 174243064475100 Local number 3 ................................................... 558 Well 174245064475800 Local number 4 ................................................... 559 Well 174308064484400 Local number 6 ................................................... 560 Well 174525064460600 Local number 7 ................................................... 561 Well 174527064460100 Local number 8 ................................................... 562 Well 174532064460300 Local number 9 ................................................... 563 Well 174329064454700 Local number 10 .................................................. 564 Well 174303064481100 Local number 11 .................................................. 565 Well 174308064482800 Local number 12 .................................................. 566 XIV GROUND-WATER WELLS, BY BASIN, FOR WHICH RECORDS ARE PUBLISHED-Continued Page Well 174316064480800 Local number 13 .................................................. 567 Well 174247064475701 Local number 14 .................................................. 568 Well 174319064454401 Local number 15 .................................................. 569 ST. THOMAS, U.S. VIRGIN ISLANDS Well 182050064580400 Local number 1 ................................................... 570 Well 182138064543100 Local number 2 ................................................... 571 Well 182138064542500 Local number 3 ................................................... 572 Well 182136064541900 Local number 4 ................................................... 573 Well 182038064550300 Local number 6 ................................................... 574 Well 182036064545200 Local number 7 ................................................... 575 Well 182038064580000 Local number 8 ................................................... 576 Well 181917064524600 Local number 9 ................................................... 577 Well 182131064541000 Local number 10 .................................................. 578 Well 182035064550200 Local number 11 .................................................. 579 ST. JOHN, U.S. VIRGIN ISLANDS Well 182010064472600 Local number 1 ................................................... 580 Well 182109064460300 Local number 2 ................................................... 581 Well 182116064451000 Local number 3 ................................................... 582 Well 182042064454500 Local number 5 ................................................... 583 Well 182044064454600 Local number 6 ................................................... 584 Well 182044064454800 Local number 7 ................................................... 585 Well 182044064454900 Local number 8 ................................................... 586 Well 182044064455000 Local number 9 ................................................... 587 Well 182044064455200 Local number 10 .................................................. 588 Well 181956064464500 Local number 11 .................................................. 589 Well 182110064430000 Local number 12 .................................................. 590 Well 181950064422300 Local number 13 .................................................. 591 Well 182048064430400 Local number 14 .................................................. 592 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1992 DISCONTINUED STREAMFLOW STATIONS The following continuous-record streamflow stations in Puerto Rico and the U.S. Virgin Islands have been discontinued or converted to partial-record stations. Daily streamflow or stage records were collected for the period of record shown for each station. Station number 50007000 50010600 50011000 50011200 50011400 50013000 50014000 50016000 50021000 50021050 50021500 50023000 50027200 50029000 50031500 50035200 50035950 50038360 50038600 50038700 50038900 50039600 50043200 50043400 50044600 50044650 50044800 50045700 50047820 50048000 50049310 50053050 50054000 50055650 50056000 50058300 50061300 50062500 50063300 50065700 50072000 50073200 50073400 50074000 50075500 50076000 50077000 50077400 50078500 50081500 50082000 50082200 50082800 50083500 50084000 50085100 50086100 50086500 50087200 50091000 Station name Quebrada de los Cedros near Isabela Rio Guajataca above Lago de Guajataca Canal Diversion Lago Guajataca Rio Guajataca below Lago Guajataca Rio Guajataca above mouth near Quebradillas Rio Camuy near Lares Rio Criminales near Lares Rio Camuy near Camuy Rio Pellejas at Central Pellejas Rio Pellejas below Central Pellejas Rio Pellejas near Utuado Rio Vivi near Central Pellejas Rio Grande de Arecibo blw. Lago dos Bocas Rio Grande de Arecibo at Central Cambalache Rio Sana Muerto near Orocovis Rio Grande de Manati at Hwy 145 at Ciales Rio Cialitos at Hwy 649 at Ciales Rio Mavilla near Corozal Rio Unibon near Morovis Rio Morovis at Morovis Rio Indio at Vega Baja Rio Cibuco at Central San Vicente Rio Usabon near Barranquitas Rio Aibonito Tributary near Aibonito Rio Guadiana near Naranjito Quebrada del Toro near Naranjito Quebrada Anones near Naranjito Rio Lajas at Toa Alta Rio de Bayamon at Hwy 174 near Bayam6n Rio de Bayamon at Bayam6n Quebrada Josefina at Piftero Avenue Rio Turabo at Borinquen Quebrada de las Quebradillas near Caguas Quebrada Caimito near Juncos Rio Valenciano near Las Piedras Quebrada Arena near Caguas Rio Canovanillas near Loiza Rio Herrera near Colonia Dolores Rio Espiritu Santo near El Verde Rio Mameyes at Hwy 191 at Mameyes Rio Fajardo at Fajardo Rio Daguao at Daguao Quebrada Palma at Daguao Rio Santiago at Naguabo Rio Blanco at Florida Rio Blanco near Florida Rio Blanco at Rio Blanco Rio Blanco at Colonia La Fe Rio Anton Ruiz at Central Pasto Viejo Rio Humacao near Humacao Rio Humacao at Hwy 3 at Humacao Rio Humacao near La Suiza Rio Guayanes near Colonia Laura Rio Guayanes near Yabucoa Rio Limones near Yabucoa Rio Guayanes at Central Roig Rio del Ingenio at Comunas Rio Guayanes at Playa Guayanes Cafto Santiago near Central Roig Rio Maunabo at Maunabo Drainage area (mi 2 ) 6.91 7.62 4.68 5.46 7.89 9.55 5.66 169 200 3.68 132 17 9.51 5.29 1.26 9.15 .13 .73 0.54 2.32 8.65 31.90 71.90 3.84 7.89 6.25 0.82 6.85 14.40 2.75 2.23 11.80 21.60 2.26 4.84 4.99 11.00 12.30 17.60 18.80 4.33 9.23 17.30 19.90 4.69 17.20 7.89 26.60 5.50 34.00 6.04 12.40 Period of record 1970 1984-89 1970 1969-70, 1984-87 1969-70, 1984-89 1969-71 1969-70 1969-73 1968-70 1972-75 1969-71 1969-75 1970-71 1969-83 1965-70 1972 1970-82 1969-70 1969-70 1968 1963,66,71 1969-72 1968-69,7] 1968-71 1971 1971 1971 1966-75 1966 1963-67 1988-91 1984-90 1969-71,73 1984-87 1971 1971 1968-73 1968-72 1968-73 1967-85 1960-63 1966-82 1972-77 1966-82 1966-82 1983-85 1973-77 1967-70 1968 1973 1983-85 1965-66, 1969-71 1969-82 1969-71 1969-71 1965-66, 1968,70 1965-66, 1968-69 1965-66, 1968-71 1965-71 1965,67, 1969-82 XVI WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1992 DISCONTINUED STREAMFLOW STATIONS--Continued Station number 50091200 50091400 50091700 50091800 50094200 50094300 50094400 50095200 50095500 50099000 50106500 50106900 50107200 50108200 50108500 50111200 50111700 50111750 50112100 50112600 50113100 50113500 50114400 50114700 50115900 50116500 50119000 50121000 50122000 50124000 50124500 50125900 50126150 50128000 50129000 50129500 50129900 50130320 50136000 50141000 50145000 50147000 50276000 Station name Rio Maunabo near Maunabo Rio Jacaboa near Lamboglia Rio Chico at Patillas Rio Chico at Providencia Rio Grande de Patillas at Patillas Rio Grande de Patillas at Providencia Rio Nigua at Pitahaya Rio Guamani at Guayama Rio Guamani near Guayama Quebrada Aguas Verdes near Salinas Rio Coamo near Coamo Rio Coamo below Lago Coamo near Coamo Rio Coamo at mouth near Santa Isabel Rio Descalabrado at Las Ollas Rio Descalabrado near Santa Isabel Rio Toa Vaca near Villalba Rio Jacaguas near Juana Diaz Rio Jacaguas below Quebrada Guanabana Rio Jacaguas near Ariis Rio Inab6n at Coto Laurel Rio Guayo near Coto Laurel Rio Inabon near Ariis Rio Bucand near Ponce Rio Bucand near PIaya de Ponce Rio Portugues at Hwy 14 at Ponce Rio Portugues at Highway 2 Bypass at Ponce Rio Matilde at Ponce Rio Tallaboa at Penuelas Rio Tallaboa at Tallaboa Rio Guayanilla nr Guayanilla Rio Guayanilla at Guayanilla Rio Duey above Diversion near Yauco Rio Yauco above Diversion Monserrate near Yauco Rio Yauco near Yauco Rio Loco near Yauco Rio Loco near Guanica Laguna Cartagena near Boquer6n Quebrada Mamey at Joyuda Rio Rosario at Rosario Rio Yahuecas near Adjuntas Rio Grande de Aftasco at El Espino Rio Culebrinas at San Sebastian Turpentine Run at Marienda1 Drainage area (mi 2 ) 12.70 4.13 6.82 4.90 27.90 29.00 5.86 8.22 12.30 0.39 46.00 65.40 69.30 13.90 18.10 21.40 53.20 56.30 59.60 11.80 30.20 25.60 28.40 20.50 19.40 24.20 31.50 18.50 20.80 8.93 27.20 45.50 8.50 21.00 0.38 16.40 15.40 108.00 16.70 2.97 Period of record 1971- 1965- 1965, 1969- 1965, 1967- 1971 1967, 1969, 1971 1971 1965, 1970- 1973 1969- 1969- 1989 1967- 1984- 1986 1967- 1967- 1965, 1967- 1966- 1966- 1966- 1989 1966- 1967- 1965, 1968- 1964- 1965- 1964- 1965- 1964- 1965- 1959- 1959- 1961- 1971- 1977- 1978- 1962- 1977- 1963- 72 69, 1969, 71, 1963-69 1984-86 1986-88 1975-86 1980-85 1959-66, 1961-63 1960-82 1963-69, 1978-86 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1992 1 INTRODUCTION The Water Resources Division of the U.S. Geological Survey, in cooperation with local and federal agencies obtains a large amount of data pertaining to the water resources of the Commonwealth of Puerto Rico and the Territory of the U.S. Virgin Islands each water year. These data, accumulated during many water years, constitute a valuable data base for developing an improved understanding of the water resources of the area. To make these data readily available to interested parties outside the Geological Survey, the data are published annually in this report series entitled "Water Resources Data for Puerto Rico and the U.S. Virgin Islands, 1992." This report includes records on both surface and ground water. Specifically, it contains: (1) Discharge records for 74 streamflow-gaging stations, stage only for 11 gaging stations, daily sediment records for 21 streamflow stations, 112 partial-record or miscellaneous streamflow stations, stage records for 9 reservoirs, and (2) water-quality records for 16 streamflow-gaging stations, and for 42 ungaged streamsites, 11 lake sites, 2 lagoons, and 1 bay; and (3) water-level records for 91 observation wells. Water-resources data for Puerto Rico for calendar years 1958-67 were released in a series of reports entitled "Water Records of Puerto Rico". Water-resources data for the U.S. Virgin Islands for the calendar years 1962-69 were released in a report entitled "Water Records of U.S. Virgin Islands." Included were records of streamflow, ground-water levels, and water-quality data for both surface and ground water. Beginning with the 1968 calendar year, surface-water records for Puerto Rico were released separately on an annual basis. Ground-water level records and water-quality data for surface and ground water were released in companion reports covering periods of several years. Data for the 1973-74 reports were published under separate covers. Water- resources data reports for 1975-76, 1977, 1978, 1979-80, 1981-82, 1983, 1984, 1985, 1986, 1987, 1988, 1989, 1990, and 1991 water years consist of one volume each and contain data for streamflow, water quality and ground water. Publications similar to this report are published annually by the Geological Survey for all States. These official Survey reports have an identification number consisting of the two-letter State abbreviation, the last two digits of the water year, and the volume number. For example, this volume is identified as "U.S. Geological Survey Water-Data Report PR-92-1". These water-data reports are for sale in paper copy or in microfiche by the National Technical Information Service, U.S. Department of Commerce, Springfield, Virginia, 22161. Beginning with the 1990 water year, all water-data reports will also be available on Compact Disc-Read Only Memory (CD-ROM). All data reports published for the current water year for the entire Nation, including Puerto Rico and the Trust Territories, will be reproduced on a single CD-ROM disc. Additional information, including- current prices, for ordering specific reports may be obtained from the District Chief at the address given on back of the title page or by telephone (809) 749-4346. A limited number of CD-ROM discs will be available for sale by the Books and Open-File Reports Section, U.S. Geological Survey, Federal Center, Box 25425, Denver, Colorado 80225. 2 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1992 COOPERATION The U.S. Geological Survey has had cooperative agreements with organizations of the Commonwealth of Puerto Rico and the Territory of the U.S. Virgin Islands for the systematic collections of water resources data since 1958. Organizations that supplied data are acknowledged in the station descriptions. Organizations that assisted in collecting data through cooperative agreements with the Survey are: Puerto Rico Environmental Quality Board Puerto Rico Aqueduct and Sewer Authority Puerto Rico Department of Agriculture Puerto Rico Industrial Development Company Puerto Rico Department of Housing Puerto Rico Highway Authority Puerto Rico Department of Natural Resources Puerto Rico Department of Health Puerto Rico Electric and Power Authority Puerto Rico Planning Board Water Resources Research Institute, University of Puerto Rico Water Resources Research Institute, College of the Virgin Islands U.S. Virgin Islands Water and Power Authority U.S. Virgin Islands Energy Office U.S. Virgin Islands Department of Planning and Natural Resources Funds were also provided by the Corps of Engineers, U.S. Army, for the collection of records at seven gaging stations published in this report. WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1992 3 SUMMARY OF HYDROLOGIC CONDITIONS Precipitation Precipitation throughout Puerto Rico during the 1992 water year (October 1991 to September 1992) averaged about 94 percent of normal. However, precipitation was 84 percent of normal in northern Puerto Rico, 102 percent of normal in southern Puerto Rico, 104 percent of normal in eastern Puerto Rico, and 91 percent of normal in western Puerto Rico. Unusually dry conditions prevailed during most of the 1992 water year except for the months of January and May. May was the wettest month of the 1992 water year. Monthly average precipitation islandwide for the 1992 water year and for the 30-year reference period 1951-1980 used to define normal rainfall, as reported by the National Oceanic and Atmospheric Administration, are listed in table 1. Table 1. Islandwide monthly precipitation and annual averages for the 1992 water year and the 30-year reference period, 1951-80 Month OCT NOV DEC JAN FEE MAR APR MAY JUN JUL AUG SEP TOTAL 1992 Water Year (inches) 4. 5, 2 , 7, 1. 2, 4, 11, 4 3 6, 5 59 .23 ,60 ,35 ,58 .61 .78 .38 .30 .37 .97 .08 .43 .68 30 -year normal ( inches) 7, 5, 4, 3, 2 2, 4 6 5 5 7 7 63 .74 .95 .32 .08 .35 .62 .63 .48 .58 .48 .28 .78 .29 Surface Water Streamflow in Puerto Rico was slightly above normal during water year 1992, based on the index stations with monthly-mean discharges about 10 percent greater than the long-term median. The 1992 monthly-mean flow, the long- term monthly median flow, and extreme monthly flows are shown for four index stations in figure 1. High and low long-term monthly median flows were recorded during water year 1992 (fig. 1). New high long- term monthly flows were recorded at Rio Grande de Manatf at Hwy 2 (50038100) during January 1992, and at Rio Inabon at Real Abajo (50112500) during January, February, and April 1992. New low long-term monthly flows were recorded at Rio Grande de Anasco near San Sebastian (50114000) during November and December 1991, and February 1992; at Rio Grande de Manati at Hwy 2 (50038100) during December 1991 and at Rio Fajardo near Fajardo (50071000) during July 1992. October 1991 was unusually dry with monthly-mean flows less than 60 percent of the long-term October median. Streamflows below the long-term monthly-median flow continued into November and December. January was exceptionally wet with above normal monthly-mean flows and historical maximum-peak flows for many stations in the streamflow network. Heavy precipitation on January 5-6, 1992 caused islandwide flash floods resulting in 23 deaths and total damage estimated in 155 million dollars. Peak discharges for 18 stations in the areas most affected by this flood are listed in table 2. WEST RfO GRANGE DE ANASCO NEAR SAN SEBASTIAN (50144000) NORTH Rfo GRANGE DE MANATl AT HWY 2 (50038100) O O LLJ W tr in o. LLJ LLJ LL g m Z)o 8 LLJ W CC LLJ CL LLJ O CC< Ow Q >j K- SOUTH RlO INAB6N AT REAL ABAJO (50112500) 1992 MONTHLY MEAN - 19965-91 MONTHLY MEDIAN LLJ O CC < Ow Q EAST RlO FAJARDO NEAR FA JAR DO (50071000) J A S 1992 Unshaded area indicates range between highest and lowest monthly mean discharges for the period of record. Figure 1.-Monthly mean discharge of selected streams in Puerto Rico. WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1992 5 Two of the most important stations in the network, Rio Grande de Lofza below Damsite (50059050) and Rio Grande de Patillas near Patillas (50092000), which peak flows are listed in table 2, were not published in this volume because records were questionable and were withheld until additional data have been collected. During February and March, streamflow declined below the long-term median at the index stations except the Rio Inabdn at Real Abajo, in the southern part of the island. Streamflows during April, May, and June increased due to excessive rainfall activity. During the last week of May, peak discharges at*many stations were as high as those of January 5-6. Streamflow conditions from July to September were variable, but stayed below the islandwide long-term median. In Vieques, Culebra, and the U.S. Virgin Islands (St. Thomas, St. Croix, and St. John), precipitation and streamflow patterns were similar to those in Puerto Rico. Rainfall in the U.S. Virgin Islands during 1992 water year was 77 percent of normal. Table 2. Peak discharges during January 5-6, 1992 and maximuma previously recorded at selected streamflow gaging stations in Puerto Rico Station number 50043000 50043800 50044830 50045010 50046000 50050900 50051150 50051800 50055000 50055225 50055390 50059050 50067000 50071000 50092000 50100200 50100450 50110900 Drainage Station area name (mi 2 ) Rio Rio Rio Rio Rio Rio de La Plata at Proyecto La Plata de La Plata at Comerio Guadiana at Guadiana de La Plata below La Plata Dam de La Plata at Hwy 2 near Toa Alta Grande de Loiza at Quebrada Arenas Quebrada Blanca at El Jagual Rio Rio Rio Rio Rio Rio Rio Rio Rio Rio Rio Grande de Loiza at Hwy 183 near San Lorenzo Grande de Loiza at Caguas Caguitas at Villa Blanca at Caguas Bairoa at Bairoa Grande de Loiza below Damsite Sabana at Sabana Fajardo near Fajardo Grande de Patillas near Patillas Lapa near Rabo del Buey Majada at La Plena Toa Vaca above Lago Toa Vaca 54. 109 9. 173 200 6, 3. 25. 89, 16, 5. 209 3, 14, 18, 9 16, 7 .8 .19 .00 .25 .0 .8 .9 .08 .96 .9 .3 .92 .7 .64 Period of record 1960-92 1988-92 1990-92 1989-92 1960-92 1978-92 1985-92 1990-92 1960-92 1991-92 1991-92 1987-92 1980-92 1962-92 1966-92 1989-92 1989-92 1989-92 Maximum discharge previously recorded Date Discharge (ftVs) 08-27-61 09-18-89 02-05-91 09-18-89 09-06-60 11-05-83 05-17-85 10-20-90 09-06-60 07-16-91 07-16-91 11-27-87 04-21-83 09-18-89 09-16-75 10-20-90 10-25-90 08-24-89 59, 32, 4, 48, 95, 11, 7, 7, 71, 2, 124, 9, 23, 14, 1, 3, 3, 600 000 600 800 500 700 400 510 500 060 742 300 010 500 800 750 820 740 Maximum for January 5-6, 1992 Day Discharge (ft'/s) 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 73 127 6 127 118 18 7 40 42 13 1 79 9 23 30 15 15 8 ,600 ,000 ,670 ,000 ,000 ,200 , 870 ,700 ,800 ,300 ,580 ,500 ,600 ,300 ,900 ,700 ,200 ,710 Ground-Water Levels Ground-water levels in the major aquifers of Puerto Rico during water year 1992 followed a seasonal trend associated with rainfall. Two significant rainfall events, one in January and the other in May, caused ground-water levels to rise; recharging the major coastal aquifers. Record-high water levels were recorded at several wells in Puerto Rico and the U.S. Virgin Islands (table 3). In the north coast limestone aquifer, ground-water levels at the Sabana Hoyos index well rose from October 1991 to January 1992 (fig. 2). Thereafter, water levels declined until mid-May, when above normal rainfall reversed the trend. A declining trend was observed during the rest of the water year. In the south coast alluvial aquifers, the Yauco and Alomar index wells recorded generally declining ground-water levels from October 1991 to January 1992 (fig. 2). In mid-May, ground-water levels rose about 8 and 2 ft at Yauco and Alomar index wells, respectively, due to intense rainfall in the area. From May until the end of the water year 1992 water-levels changed very little at the Yauco index well and declined at the Alomar index well due to ground-water withdrawals for public irrigation and industrial use. 6 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1992 Ground-water levels in the U.S. Virgin Islands in the observation well 11 at Guinea Gut, St. John followed a seasonal trend associated with rainfall (fig. 2). Water-levels were affected by rainfall events during November and December 1991 and on January and May 1992. From January to early-May 1992 the water-level in Guinea Gut well dropped 12.0 ft in response to below normal rainfall in the area. Table 3. Highest ground-water levels recorded during 1992 water year and previous high ground-water levels at selected wells in Puerto Rico and the U.S. Virgin Islands [PR, Puerto Rico; St.C, St. Croiz; St.T, St. Thomas; St.J, St. John; mm-dd-yy, month-day-year, ft-blsd, feet below land surface datum, mm-yy, month-year] 1992 high Well Local water name number Location (ft-blsd) Saltos 1 165 PR 38.75 La Esperanza PN-2 PR 8.07 2 Jardin Botdnico PN-19 PR 4.04 3 HW-TW-05B HW-TW-05B PR 7.89 RM 5 RM 5 PR 7.48 WAPA-23a 15 St.C 55.29 VIEO-1 7 St.T 68.23 VIEO-2 12 St.J 21.47 VIEO-3 13 St.J 52.04 Date (mm-dd-yy) 09-23-92 09-26-92 06-08-92 06-09-92 06-10-92 06-09-92 05-26-92 05-26-92 10-01-91 02-11-92 06-05-92 06-06-92 06-07-92 06-08-92 12-03-91 12-04-91 12-05-91 Previous high water (ft-blsd) 38.81 8.12 6.37 9.40 8.15 56.84 71.88 23.48 52.21 Date (mm-dd-yy) 10-05-90 10-07-90 10-08-90 10-22-90 09-30-91 08-25-88 10-26-90 02-13-91 06-16-91 05-23-91 05-24-91 05-25-91 05-26-91 09-30-91 Period of record (mm-yy) 1-82 to 9-92 7-89 to 9-92 6-91 to 9-92 4-88 to 9-92 3-89 to 9-92 2-90 to 9-92 5-91 to 9-92 5-91 to 9-92 5-91 to 9-92 VIEO-4 14 St.J 9.95 06-05-92 10.50 09-29-91 5-91 to 9-92 i i 25 30 35 I I WELL 70, SABANA HOYOS, PUERTO RICO J_____1______I______I_____I______I_____I______I_____I______1______I OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1991 1992 I 23 Q 1 Ul DO 31 39 T i WELL 87, ALOMAR 1, PUERTO RICO OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1991 1992 WELL 11, GUINEA GUT ST. JOHN, U.S. VIRGIN ISLANDS. 1_____I_____I_____1_____I_____1_____I_____I_____I_____I_____I NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1991 1992 Figure 2.—Ground-water levels at selected wells in Puerto Rico and the U.S. Virgin Islands. 3 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1992 Water Quality In water year 1992, the U.S. Geological Survey, in cooperation with local government agencies, completed the eighth year of sampling for the constituents listed in table 4. These constituents were added to the water quality monitoring program in 1985 and are in addition to the major chemical constituents and physical properties monitored in the continuing water quality monitoring program in Puerto Rico. The highest concentration of selected constituents detected during water year 1992, along with the stations at which these concentrations were detected, are summarized in table 4. Table 4. Surface-water quality stations in Puerto Rico with highest concentration of selected constituents during water year 1992 [All constituent concentrations are in milligrams per liter; MBAS, Methylene blue active substance] Station number 50106500 50129700 50124700 50055400 50043000 50149100 50149100 50055250 50055250 Rio Rio Rio Rio Rio Rio Rio Rio Rio Station Portugu^s name near Constituent Concentration Ponce Loco at Gucinica Guayanilla Grande de at Central Arecibo near de La Plata Culebrinas Culebrinas CagOitas at CagUitas at at near near Hwy Hwy Ruf ina Utuado Proyecto La Aguada Aguada 30 at 30 at Plata Caguas Caguas Sulf ids Boron Manganese Iron Iron Zinc Cyanide Phenols MBAS 0. 0. 1. 14 14 0. 0. 0. 1. 8 .7 ,2 .12 ,06 .011 .7 The presence of high concentrations of fecal coliform (FC) and fecal streptococci (FS) bacteria continued to be the principal surface-water quality problem in Puerto Rico during water year 1992. Bacteria concentration exceeding one million colonies per hundred milliliters of raw water were not observed at any sampling station during this water year as observed in previous years. The highest concentrations observed during this year were in the San Juan metropolitan area monitoring stations (figs. 3 and 4), which has the highest population density in Puerto Rico. In addition to the effluent from the San Juan metropolitan area, the streams also receive effluent from the upper basin sewage treatment plants servicing urban and suburban zones. The main sources of contamination in surface-water systems in Puerto Rico are discharges of liquid wastes from industrial and municipal sources. The highest concentration of fecal coliforms and fecal streptococcus bacteria in surface-waters occurred in heavily populated and industrialized areas of the island. Elevated concentration of suspended sediment are a common problem in many streams in Puerto Rico, especially in the coastal areas. Suspended sediment concentrations are of concern because the deposition of these sediments is rapidly reducing the storage capacities of reservoirs used for water supply. Suspended sediment concentration were monitored at twenty one sites in Puerto Rico during the 1992 water year as part of the cooperative program between the U.S. Geological Survey and various other Commonwealth and Federal agencies. WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1992 9 SPECIAL NETWORKS AND PROGRAMS National Stream Quality Accounting Network (NASQAN) is a nationwide data-collection network designed by the U.S. Geological Survey to meet many of the information needs of government agencies and other groups involved in natural or regional water-quality planning and management. The 500 or so sites on NASQAN are generally located at the downstream ends of hydrologic accounting units designated by the U.S. Geological Survey Office of Water Data Coordination in consultation with the Water Resources Council. The objectives of NASQAN are (1) to obtain information on the quality and quantity of water moving within and from the United States through a systematic and uniform process of data collection, summarization, analysis, and reporting such that the data may be used for, (2) description of the areal variability of water quality in the Nation's rivers through analysis of data from this and other programs, (3) detection of changes or trends with time in the pattern of occurrence of water-quality characteristics, and (4) providing a nationally consistent data base useful for water-quality assessment and hydrologic research. EXPLANATION OF RECORDS The surface-water and ground-water records published in this report are for the 1992 water year that began October 1, 1991 and ended September 30, 1992. A calendar of the water year is provided on the inside of the front cover. The records contain streamflow data, water-quality data for surface and ground water, and ground-water-level data. The locations of the stations and wells where the data were collected are shown in figures 3 to 10. The following sections of the introductory text are presented to provide users with a more detailed explanation of how the hydrologic data published in this report were collected, analyzed, computed, and arranged for presentation. Station Identification Numbers Each data station, whether streamsite or well, in this report is assigned a unique identification number. This number is unique in that it applies specifically to a given station and to no other. The number usually is assigned when a station is first established and is retained for that station indefinitely. The systems used by the U.S. Geological Survey to assign identification numbers for surface-water stations and for ground-water well sites differ, but both are based on geographic location. The "downstream order" system is used for regular surface-water stations and the "latitude- longitude" system is used for wells. Downstream Order System Since October 1, 1950, the order of listing hydrologic-station records in Survey reports is in a downstream direction along the main stream. All stations on a tributary entering upstream from a main-stream station are listed before that station. A station on a tributary that enters between two main-stream stations is listed between them. A similar order is followed in listing stations in first rank, second rank, and other ranks of tributaries. As an added means of identification, each hydrologic station and partial-record station has been assigned a station number. These are in the same downstream order used in this report. In assigning station numbers, no distinction is made between partial-record stations and other stations; therefore, the station number for a partial-record station indicates downstream order position in a list made up of both types of stations that may be established; hence, the numbers are not consecutive. The complete 8-digit number for each station such as 50028000, which appears just to the left of the station name, includes the 2-digit part number "50" plus the 6-digit downstream order number "028000." Latitude-Longitude System The 8-digit downstream order station numbers are not assigned to wells and miscellaneous sites where only random water-quality samples or discharge measurements are taken. The well and miscellaneous site numbering system of the U.S. Geological Survey is based on the grid system of latitude and longitude. The system provides the geographic location of the well or miscellaneous site and a unique number for each site. The number consists of 15 digits. The first 6 digits denote the degrees, minutes, and seconds of latitude, the next 7 digits denote degrees, minutes, and seconds of longitude, and the last 2 digits (assigned sequentially) identify the wells or other sites within a 1-second grid. The numbers shown in the grid correspond to the local numbers assigned to each well as visited in the field. An example is well 16 (fig. 12). iB'tlO ATLANTIC OCEAN •->> T , "'-^"> / LJ-. >^r^ ,4^>?:• \ ' rS"~^f V^^ •<••' VV.*' "- fv-~ -^ x^v y^xtj^T- • 1*" -"'' -*• ^• 10 20 30 KILOMETERS 20 MILES CARIBBEAN SEA. EXPLANATION FECAL STREPTOCOCCI • < 1000 • 1000-10,000 10,000-100,000 100,000-1,000,000 > 1,000,000 Figure 3.--Location of fecal coliform bacteria concentration at sampled sites. !800' ATLANTIC OCEAN I / ' v j X ^ iU'/'lJj'C/ rw-?1 CARIBBEAN SEA EXPLANATION FECAL STREPTOCOCCI < 1000 1000-10,000 I 10,000-100,000 ; 100,000-1,000,000 > 1,000,000 Figure 4.--Location of fecal streptococci bacteria concentration at sampled sites. ATLANTIC OCEAN p? , ^" J »0157 *,.- "ji-nv.v ,-' Vr, u,.. •*-'-'•£* r\ \\ V-'x *•—»,. 1440A '~~i «*,.•'-.• tfll\r-, ^ U, ,') ''UK: V* l^jf 'y \ i, \ 0284A/±°27750 ——^ /N A046° <!i..<A0491 ^ : n61Q V /^V^ *••**•"" "*r"h A1478 •'• 1L < V « i — A >- -A0490 A Y 2 °642 "V^i^/? ( \ \\ ^" .. ^_ / :r J ',v t ^38320 A045010 ' ', ''' A048770 ' ^ A A"638 '°67A • ^ / "^-. L A0148 S ' A0350 i Al ^ ^0450 ' " M -A A0635 • ,^ { "^.-Ol05 ^ j^8° >* -"^'"X ^^,,0312']// .°472 0535 ^"059° °618' °6344^ ^6554-.-'T"'"" '^"V ^\ .*"" \ 0340 A '( : - 047560 A 055390A A 0569 0750 ^ ' ^^' - [ o \ </ 0146 A i ,-i ^^ ^ i^. ! **A A , I -^ "-M ."' ^ A / < ' . ..n/1(:n 044830 055lAA4 A A Q55750 ' > , > X r , •- •' ^ B 032590 .fA? A 04755°H 055225/A A0564 ^ ) \1^ i <.1415 - v / < 025155 • 'K' ' ; °438 °55° \ ^V- A .. , ^ J 1138 A ,,„,. • A"09 A A ^A 051310 -^ f\ ?"-&•*•?- ,,n -,rc^ 1364A ' . »nnn ^* i •^•^ V'?1 / >' 131990 Aj' _/ / '; •^^*—J w :-/ 1150A A11140 125780 1242A ( I 11439oA V Am5 A1080 ;i ^ / 1 °°2A 039990 ' 100450 /••- 053025 A g , f\ "'-» \4 C'.-« 1^:>T O.j,, ^V,, ^«v^r J 10 20 > 1242A f / ii«9q4 ) Ams ^ ^ /' ^ 1UU46U y- ^"~^\ ^7^""^ifc^?^^ '.i.^ i,""' C-'"1 20 30 KlLCWif-TEHS SE4 VJ, ! °^5 .? J'*6 -^- / .•" ' A _ / .--•' -*u EXPLANATION 30 KlLCWif-TEHS 2D MILES 0905 CONTINUOUS STREAMFLOW STATION AND NUMBER I 1415 LAKE-ELEVATION STATION Figure 5.--Location of surface-water stations in Puerto Rico. ATLANTIC OCEAN <' , •* ^9920 ,0105 ^r* 027250 ^JT 027090 ^•025110 '^026050 f038320 047990W" _ 1^638 y^^^ $590 0588 TTT '/< > \ ~. ••v\ •%/Yp (\ ' 1336 - , / J .' \ ^ / t K W205 ^020050 11 so > 1^ 140 ^*^*-- ^ /' Y > / \ IT 0430 0820 IT ...:/" 'I 0835 0865 '0399 0920 W~ ' '-- ,0910 s IT ' W 1* 10 10 3C KILOMETERS 20 MILLS CARIBBEAN SEA EXPLANATION QUALITY OF WATER STATIONS ^0430 BIOLOGICAL }f 0820 CHEMICAL ^f 0280 SEDIMENT (Daily) Y"0910 SEDIMENT (Bi-monthly) Figure 6.--Location of water-quality stations in Puerto Rico. Co IB'30' 67'1: 67'00 30' EXPLANATION A LOW-FLOW PARTIAL-RECORD STATION 1107 STATION IDENTIFICATION NUMBER 1800' 10 20 I 10 30 KILOMETERS cO MILES CARIBBEAN Figure 7--Location of low-flow partial-record stations in southwest Puerto Rico. 65 30 ATLANTIC OCEAN J65 ,200 *W-\ 'tit' \ '•-.,, *;>. V ''- CR-TW-6 CR-TW-9A C ' , CR-TW-1 CR-JW-3 CR-TW-2A CR-T:W-4 /CR-TW-2B CR-TW-7 CR-TW-8 i CR-TW-2C <; 30 KILOMtltRS 20 MILES CARIBBEAN SEA EXPLANATION e WELL AND WELL NUMBER Figure 8-Location of ground-water stations in Puerto Rico. 65'00' 64W i3'24' ST THOMAS 01234 KILOMETER 01234 MILES 64 50' 6440' X^/y, ? 18 18 : KILOMETERS 01 234 JslLOMETERS 1234 MILE A 3490 SURFACE-WATER STATION AND NUMBER Figure 9-Location of surface-water stations in the U.S. Virgin Islands. 17 65'!05 ! 65W 55 s 64'50' !8'24! ST, THOMAS :8 !'20' •— V _\_^v 10 01234 KILOMETERS 01234 MILES ' r^ 17 45 ! 64 40 s ST. JOHN 234 KILOMETERS EXPLANATION 1 WELL AND WELL NUMBER 64 =50 ! 45 ! 40' 64°35 ! ST CROIX 17-45T 11 \ V12 „.— t S13 K\ I q r/ kv;r*2^i34 Frederiksied 01234 KILOMETERS 01234 MILES Figure 10r-Location of ground-water stations in the U.S. Virgin Islands. 18 25-00' Isla de Vieques, RR. .. , .. X...>- / >vJk ' EXPLANATION A2310 SURFACE-WATER STATION AND NUMBER 65'15W Isla de Cu'ebra, RR. 2 KILOMETERS 2 r" EXPLANATION 2145 SURFACE-WATER STATION AND NUMBER Figure 11 .--Location of surface-water stations in Vieques and Culebra Islands. 19 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1992 66°53' 52' 51' 50' 49' 48' 66°47' IflOn ••' or iflOrifV i/ocq' 134 132^ I3r \ V •l6 ^ •27 •74 C</c COORDINATES FOR WELLS 27 (180150066474000) AND 74 (180136066471000) COORDINATES FOR WELLS 132 (180133066503300) AND 134 (180120066603200) COORDINATES FOR WELL 131 (160058066502700) COORDINATES FOR WELL 16 (175922066405800) Figure 12.--Grid showing system for numbering wells and miscellaneous sites (latitude and longitude). Records of Stage and Water Discharge Records of stage and water discharge may be complete or partial. Complete records of discharge are those obtained using a continuous stage-recording device through which either instantaneous or mean daily discharges may be computed for any time, or any period of time, during the period of record. Complete records of lake or reservoir content, similarly, are those for which stage or content may be computed or estimated with reasonable accuracy for any time, or period of time. They may be obtained using a continuous stage-recording device, but need not be. Because daily mean discharges and end-of-day contents commonly are published for such stations, they are referred to as "daily stations." By contrast, partial records are obtained through discrete measurements without using a continuous stage-recording device and pertain only to a few flow characteristics, or perhaps only one. The nature of the partial record is indicated by table title such as "Low-flow partial records." Records of miscellaneous discharge measurements or of measurements from special studies, such as low-flow seepage studies, may be considered as partial records, but they are presented separately in this type of report. Location of all complete-record stations for which data are given in this report are shown in figures 5 and 8. Data Collection and Computation The data obtained at a complete-record gaging station on a stream or canal consists of a continuous record of stage, individual measurements of discharge throughout a range of stages, and notations regarding factors that may affect the relationships between stage and discharge. These data, together with supplemental information, such as weather records, are used to compute daily discharges. The data obtained at a complete-record gaging station on a lake or reservoir consist of a record of stage and of notations regarding factors that may affect the relationship between stage and lake content These data are used with stage-area and stage-capacity curves or tables to compute water-surface areas and lake storage. Continuous records of stage are obtained with analog recorders that trace continuous graphs of stage or with digital recorders that punch stage values on paper tapes at selected time intervals or electronic satellite data collector platforms that receive stage values at selected time intervals. Measurements of discharge are made with current meters using methods adapted by the Geological Survey as a result of experience accumulated since 1880. These methods are described in standard textbooks, in Water-Supply Paper 2175, and in U.S. Geological Survey Techniques of Water- Resources Investigations, Book 3, Chapter A6. 20 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1992 In computing discharge records, results of individual measurements are plotted against the corresponding stages, and stage-discharge relation curves are then constructed. From these curves, rating tables indicating the approximate discharge for any stage within the range of the measurements are prepared. If it is necessary to define extremes of discharge outside the range of the current-meter measurements, the curves are extended using: (1) logarithmic plotting; (2) velocity-area studies; (3) results of indirect measurements of peak discharge, such as slope-area or contracted-opening measurements, and computations of flow-over-dams or weirs; or (4) step-backwater techniques. Daily mean discharges are computed by applying the daily mean stages (gage heights) to the stage-discharge curves or tables. If the stage-discharge relation is subject to change because of frequent or continual change in the physical features that form the control, the daily mean discharge is determined by the shifting-control method, in which correction factors based on the individual discharge measurements and notes of the personnel making the measurements are applied to the gage heights before the discharges are determined from the curves or tables. This shifting-control method also is used if the stage-discharge relation is changed temporarily because of aquatic growth or debris on the control. At some stations the stage-discharge relation is affected by changing stage; at these stations the rate of change in stage is used as a factor in computing discharge. In computing records of lake or reservoir contents, it is necessary to have available from surveys, curves or tables defining the relationship of stage and contents. The application of stage to the stage-content curves or tables gives the contents from which daily, monthly or yearly changes then are determined. If the stage-content relationship changes because of deposition of sediment in a lake or reservoir, periodic surveys may be necessary to redefine it. Even when this is done, as time between the last survey increases, the contents computed may increase in error. Discharges over lake or reservoir spillways are computed from stage-discharge relationships much as other stream discharges are computed. For some gaging stations there are periods when no gage-height record is obtained, or the recorded gage height is so faulty that it cannot be used to compute daily discharge or contents. This happens when the recorder stops or otherwise fails to operate properly, intakes are plugged, the float is loose in the well, or for various other reasons. For such periods, the daily discharges are estimated from the recorded range in stage, previous or following record, discharge measurements, weather records, and comparison with other station records from the same or nearby basins. Likewise, daily contents may be estimated from operator's logs, previous or following record, inflow-outflow studies, and other information. Information explaining how estimated daily-discharge values are identified in station records is included in the next two sections, "Data Presentation" (REMARKS paragraph) and "Identifying Estimated Daily Discharge." Data Presentation Steamflow data in this report are presented in a new format that is considerably different from the format in data reports prior to the 1992 water year. The major changes are that statistical characteristics of discharge now appear in tabular summaries following the water-year data table and less information is provided in the text or station manuscript above the table. These changes represent the results of a pilot program to reformat the annual water-data report to meet current user needs and data preferences. The records published for each continuous-record surface-water discharge station (gaging station) now consist of four parts, the manuscript or station description; the data table of daily mean values of discharge for the current water year with summary data; a tabular statistical summary of monthly mean flow data for a designated period, by water year; and a summary statistics table that includes statistical data of annual, daily, and instantaneous flows as well as data pertaining to annual runoff, 7-day low-flow minimum, and flow duration. Station manuscript The manuscript provides, under various headings, descriptive information, such as station location; period of record; historical extremes outside the period of record; record accuracy; and other remarks pertinent to station operation and regulation. The following information, as appropriate, is provided with each continuous record of discharge or lake content. Comments to follow clarify information presented under the various headings of the stations descriptions. LOCATION.--Information on locations is obtained from the most accurate maps available. The location of the gage with respect to the cultural and physical features in the vicinity and with respect to the reference place mentioned in the station name is given. WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1992 21 DRAINAGE AREA.—Drainage areas are measured using the most accurate maps available. Drainage areas are updated as better maps become available. PERIOD OF RECORD.—This indicates the period for which there are published records for the station or for an equivalent station. An equivalent station is one that was in operation at a time that the present station was not, and whose location was such that records from it can reasonable be considered equivalent with records from the present station. REVISED RECORDS.—Because of new information, published records occasionally are found to be incorrect, and revisions are printed in later reports. Listed under this heading are all the reports in which revisions have been published for the station and the water years to which the revisions apply. If a revision did not include daily, monthly, or annual figures of discharge, that fact is noted after the year dates as follows: "(M)" means that only the instantaneous maximum discharge was revised; "(m)" that only the instantaneous minimum was revised; and "(P)" that only peak discharges were revised. If the drainage area has been revised, the report in which the most recently revised figure was first published is given. GAGE.-The type of gage in current use, the datum of the current gage, and a condensed history of the types, locations, and datums of previous gages are given under this heading. REMARKS.-All periods of estimated daily-discharge record will either be identified by date in this paragraph of the station description for water-discharge stations or flagged in the daily-discharge table. (See next section, "Identifying Estimated Daily Discharge.") If a remarks statement is used to identify estimated record, the paragraph will begin with this information presented as the first entry. The paragraph is also used to present information relative to the accuracy of the records, to special methods of computations, to conditions that affect natural flow at the station and, possibly, to other pertinent items. For reservoir stations, information is given on the dam forming the reservoir, the capacity, outlet works and spillway, and purpose and use of the reservoir. COOPERATION.—Records provided by a cooperating organization or obtained for the Geological Survey by a cooperating organization are identified here. EXTREMES OUTSIDE PERIOD OF RECORD.-Included here is information concerning major floods or unusually low flows that occurred outside the stated period of record. The information may or may not have been obtained by the U.S. Geological Survey. REVISIONS.--If a critical error in published records is discovered, a revision is included in the first report published following discovery of the error. Although rare, occasionally the records of a discontinued gaging station may need revision. Because, for these stations, there would be no current or, possibly, future station manuscript published to document the revision in a "Revised Records" entry, users of data for these stations who obtained the record from previously published data reports may wish to contact the District office to determine if the published records were ever revised after the station was discontinued. Of course, if the data were obtained by computer retrieval, the data would be current and there would be no need to check because any published revision of data is always accompanied by revision of the corresponding data in computer storage. Manuscript information for lake or reservoir stations differs from that for stream stations in the nature of the "Remarks" and in the inclusion of a skeleton stage-capacity table when daily contents are given. Data table of daily mean value The daily table of discharge records for stream-gaging stations gives mean discharge for each day of the water year. In the monthly summary for the table, the line headed "TOTAL" gives the sum of the daily figures for each month; the line headed "MEAN" gives the average flow in cubic feet per second for the month; and the lines headed "MAX" and "MIN" give the maximum and minimum daily mean discharges, respectively, for each month. Discharge for the month also is usually expressed in cubic feet per second per square mile (line headed "CFSM"); or in inches (line headed "IN"); or in acre-feet (line headed "AC-FT"). Figures for cubic feet per second per square mile and runoff in inches or in acre- feet may be omitted if there is extensive regulations or diversion or if the drainage area includes large noncontributing areas. 22 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1992 Statistics of monthly mean data A tabular summary of the mean (line headed "MEAN"), maximum (line headed "MAX"), and minimum (line headed "MIN") of monthly mean flows for each month for a designated period is provided below the mean values table. The water years of the first occurrence of the maximum and minimum monthly flow are provided immediately below those figures. The designated period will be expressed as "FOR WATER YEARS __-__, BY WATER YEAR (WY)," and will list the first and last water years of the range of years selected from the PERIOD OF RECORD paragraph in the station manuscript. It will consist of all of the station records within the specified water years, including complete months of record for partial water years, if any, and may coincide with the period of record for the station. The water years for which the statistics are computed will be consecutive, unless a break in the station record is indicated in the manuscript. Summary statistics A table titled "SUMMARY STATISTICS" follows the statistics of monthly mean data tabulation. This table consists of four columns, with the first column containing the line headings of the statistics being reported. The table provides a statistical summary of yearly, daily, and instantaneous flows, not only for the current water year but also for the previous calendar year and for a designated period, as appropriate. The designated period selected, "WATER YEARS __-__," will consist of all of the station records within the specified water years, inclusive, including complete months of record for partial water years, if any, and may coincide with the period of record for the station. The water years for which the statistics are computed will be consecutive, unless a break in the station record is indicated in the manuscript. All of the calculations for the statistical characteristics designated ANNUAL (see line headings below.), except for the "ANNUAL 7-DAY MINIMUM" statistic, are calculated for the designated period using complete water years. The other statistical characteristics may be calculated using partial water years. The date or water year, as appropriate, of the first occurrence of each statistic reporting extreme values of discharge is provided adjacent to the statistic. Repeated occurrences may be noted in the REMARKS paragraph of the manuscript or in footnotes. Because the designated period may not be the same as the station period of record published in the manuscript, occasionally the dates of occurrence listed for the daily and instantaneous extremes in the designated- period column may not be within the selected water years listed in the heading. When this occurs, it will be noted in the REMARKS paragraph or in footnotes. Selected streamflow duration curve statistics and runoff data are also given. Runoff data may be omitted if there is extensive regulation or diversion of flow in the drainage basin. The following summary statistics data, as appropriate, are provided with each continuous record of discharge. Comments to follow clarify information presented under the various line headings of the summary statistics table. ANNUAL TOTAL.—The sum of the daily mean values of discharge for the year. At some stations the annual total discharge is adjusted for reservoir storage or diversion. The adjusted figures are identified by a symbol and corresponding footnotes. ANNUAL MEAN.—The arithmetic mean of the individual daily mean discharges for the year noted or for the designated period. At some stations the yearly mean discharge is adjusted for reservoir storage or diversion. The adjusted figures are identified by a symbol and corresponding footnotes. HIGHEST ANNUAL MEAN.—The maximum annual mean discharge occurring for the designated period. LOWEST ANNUAL MEAN.--The minimum annual mean discharge occurring for the designated period. HIGHEST DAILY MEAN.—The maximum daily mean discharge for the year or for the designated period. LOWEST DAILY MEAN.-The minimum daily mean discharge for the year or for the designated period. ANNUAL 7-DAY MINIMUM.—The lowest mean discharge for 7 consecutive days for a calendar year or a water year. Note that most low-flow frequency analyses of annual 7-day minimum flows use a climatic year (April 1 - March 31). The date shown in the summary statistics table is the initial date of the 7-day period. (This value should not be confused with the 7-day 10-year low-flow statistics.) 23 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1992 INSTANTANEOUS PEAK FLOW.—The maximum instantaneous discharge occurring for the water year or for the designated period. Note that secondary instantaneous peak discharges above a selected base discharge are stored in District computer files for stations meeting certain criteria. Those discharge values may be obtained by writing to the District Office. (See address on back of the title page of this report.) INSTANTANEOUS PEAK STAGE.—The maximum instantaneous stage occurring for the water year or for the designated period. If the dates of occurrence for the instantaneous peak flow and instantaneous peak stage differ, the REMARKS paragraph in the manuscript or a footnote may be used to provide further information. INSTANTANEOUS LOW FLOW.-The minimum instantaneous discharge occurring for the water year or for the designated period. ANNUAL RUNOFF.—Indicates the total quantity of water in runoff for a drainage area for the year. Data reports may use any of the following units of measurements in presenting annual runoff data: Acre-foot (AC-FT) is the quantity of water required to cover 1 acre to a depth of 1 foot and is equivalent to 43,560 cubic feet or about 326,000 gallons or 1,233 cubic meters. Cubic feet per second per square mile (CFSM) is the average number of cubic feet of water flowing per second from each square mile of area drained, assuming the runoff is distributed uniformly in time and area. Inches (INCHES) indicates the depth to which the drainage area would be covered if all of the runoff for a given time period were uniformly distributed on it. 10 PERCENT EXCEEDS.-The discharge that is exceeded by 10 percent of the flow for the designated period. 50 PERCENT EXCEEDS.-The discharge that is exceeded by 50 percent of the flow for the designated period. 90 PERCENT EXCEEDS.-The discharge that is exceeded by 90 percent of the flow for the designated period. Data collected at partial-record stations follow the information for continuous-record sites. Data for partial-record discharge stations are presented in a table of discharge measurements at low-flow partial-record stations. These measurements are generally made in times of drought to give better areal coverage to those events. Those measurements and others collected for some special reason are called measurements at miscellaneous sites. Identifying Estimated Daily Discharge Estimated daily-discharge values published in the water-discharge tables are identified by flagging individual daily values with the letter symbol "e" and printing a table footnote, "e Estimated." Accuracy of the Records The accuracy of streamflow records depends primarily on: (1) The stability of the stage-discharge relation or, if the control is unstable, the frequency of discharge measurements; and (2) the accuracy of measurements of stage, measurements of discharge, and interpretation of records. The accuracy attributed to the records is indicated under "REMARKS." "Excellent" means that about 95 percent of the daily discharges are within 5 percent of the true; "good," within 10 percent; and "fair," within 15 percent. Records that do not meet the criteria mentioned, are rated "poor." Different accuracies may be attributed to different parts of a given record. Daily mean discharges in this report are given to the nearest hundredth of a cubic foot per second for values less than 1 ftVs; to the nearest tenth between 1.0 and 10 ft3/s; to whole numbers between 10 and 1,000 ft3/s; and to 3 significant figures for more than 1,000 ft3/s. The number of significant figures used is based solely on the magnitude of the discharge value. The same rounding rules apply to discharges listed for partial-record stations and miscellaneous sites. 24 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1992 Information used in the preparation of the records in this publication, such as discharge-measurement notes, gage- height records, temperature measurements, and rating tables are on file in the Caribbean District office. Also, most of the daily mean discharges are in computer-readable form and have been analyzed statistically. Information on the availability of the unpublished information or on the results of statistical analyses of the published records may be obtained from the District office. Records of Surface-Water Quality Records of surface-water quality ordinarily are obtained at or near stream-gaging stations because interpretation of records of surface-water quality nearly always requires corresponding discharge data. Records of surface-water quality in this report may involve a variety of types of data and measurement frequencies. Classification of Records Water-quality data for surface-water sites are grouped into one of three classifications. A continuing-record station is a site where data are collected on a regularly scheduled basis. Frequency may be once or more times daily, weekly, monthly, or quarterly. A partial-record station is a site where limited water-quality data are collected systematically over a period of years. Frequency of sampling is usually less than quarterly. A miscellaneous sampling site is a location other than a continuing or partial-record station, where random samples are collected to give better areal coverage to define water-quality conditions in the river basin. A careful distinction needs to be made between "continuing records" as used in this report and "continuous recordings," which refers to a continuous graph or a series of discrete values punched at short intervals on a paper tape. Some records of water quality, such as temperature and specific conductance, may be obtained through continuous recordings; however, because of costs, most data are obtained only monthly or less frequently. Locations of stations for which records on the quality of surface water appear in this report are shown in figure 6. Arrangement of Records Water-quality records collected at a surface-water daily record station are published immediately following that record, regardless of the frequency of sample collection. Station number and name are the same for both records. Where a surface-water daily record station is not available or where the water quality differs significantly from that at the nearby surface-water station, the continuing water-quality record is published with its own station number and name in the regular downstream-order sequence. Water-quality data for partial-record stations and for miscellaneous sampling sites appear in separate tables following the table of discharge measurement at miscellaneous sites. On-site Measurements and Sample Collection In obtaining water-quality data, a major concern needs to be assuring that the data obtained represent the in situ quality of the water. To assure this, certain measurements, such as water temperature, pH, and dissolved oxygen, need to be made onsite when the samples are taken. To assure that measurements made in the laboratory also represent the in situ water, carefully prescribed procedures need to be followed in collecting the samples, in treating the samples to prevent changes in quality pending analysis, and in shipping the samples to the laboratory. Procedures for onsite measurements and for collecting, treating, and shipping samples are given in publications on "Techniques of Water- Resources Investigations," Book 1, Chap. D2; Book 3, Chap. C2; Book 5, Chap. Al, A3, and A4. Detailed information on collecting, treating, and shipping samples may be obtained from the Geological Survey District office. One sample can define adequately the water quality at a given time if the mixture of solutes throughout the stream cross section is homogeneous. However, the concentration of solutes at different locations in the cross section may vary widely with different rates of water discharge, depending on the source of material and the turbulence and mixing of the stream. Some streams must be sampled through several vertical sections to obtain a representative sample needed for an accurate mean concentration and for use in calculating load. All samples obtained for the National Stream Quality Accounting Network (see definitions) are obtained from at least several verticals. Whether samples are obtained from the centroid of flow or from several verticals, depends on flow conditions and other factors which must be evaluated by the collector. 25 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1992 Chemical-quality data published in this report are considered to be the most representative values available for the stations listed. The values reported represent water-quality conditions at the time of sampling as much as possible, consistent with available sampling techniques and methods of analysis. In the rare case where an apparent inconsistency exists between a reported pH value and the relative abundance of carbon dioxide species (carbonate and bicarbonate), the inconsistency is the result of a slight uptake of carbon dioxide from the air by the sample between measurement of pH in the field and determination of carbonate and bicarbonate in the laboratory. For chemical-quality stations equipped with digital monitors, the records consist of daily maximum, minimum, and mean values for each constituent measured and are based upon hourly punches beginning at 0100 hours and ending at 2400 hours for the day of record. More detailed records, when available, (hourly values) may be obtained from the U.S.G.S. District office whose address is given on the back of the title page of this report. Water Temperature Water temperatures are measured at most of the water-quality stations. In addition, water temperatures are taken at time of discharge measurements for water-discharge stations. For stations where water temperatures are taken manually once or twice daily, the water temperatures are taken at about the same time each day. Large streams have a small diurnal temperature change; shallow streams may have a daily range of several degrees and may follow closely the changes in air temperature. Some streams may be affected by waste-heat discharges. At stations where recording instruments are used, either mean temperatures or maximum and minimum temperatures for each day are published. Water temperatures measured at the time of water-discharge measurements are on file in the District office. Sediment Suspended-sediment concentrations are determined from samples collected by using depth-integrating and pumping sediment samplers. Samples usually are obtained at several verticals in the cross section, or a single sample may be obtained at a fixed point and a coefficient applied to determine the mean concentration in the cross sections. During periods of rapidly changing flow or rapidly changing concentration, samples may have been collected more frequently (twice daily or hourly). The published sediment discharges for days of rapidly changing flow or concentration were computed by the subdivided-day method (time-discharge weighted average). Therefore, for those days when the published sediment discharge value differs from the value computed as the product of discharge times mean concentration times 0.0027, the reader can assume that the sediment discharge for that day was computed by the subdivided-day method. For periods when no samples were collected, daily discharges of suspended sediment were estimated on the basis of water discharge, sediment concentrations observed immediately before and after the periods, and suspended- sediment loads for other periods of similar discharge. At other stations, suspended-sediment samples were collected periodically at many verticals in the stream cross section. Although data collected periodically may represent conditions only at the time of observations, such data are useful in establishing seasonal relations between quality and streamflow and in predicting long-term sediment-discharge characteristics of the stream. In addition to the records of suspended-sediment discharge, records of the periodic measurements of the particle- size distribution of the suspended sediment and bed material are included for some stations. Laboratory Measurements Sediment samples, samples for biochemical-oxygen demand (BOD), samples for indicator bacteria, and daily samples for specific conductance are analyzed locally. All other samples are analyzed in the Geological Survey laboratories in Denver, Co. or Ocala, Ra. Methods used in analyzing sediment samples and computing sediment records are given in TWRI, Book 5, Chap. Cl. Methods used by the Geological Survey laboratories are given in TWRI, Book 1, Chap. D2; Book 3, Chap. C2; Book 5, Chap. Al, A3, and A4. 26 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1992 Data Presentation For continuing-record stations, information pertinent to the history of station operation is provided in descriptive headings preceding the tabular data. These descriptive headings give details regarding location, drainage area, period of record, type of data available, instrumentation, general remarks, cooperation, and extremes for parameters currently measured daily. Tables of chemical, physical, biological, radiochemical data, and so forth, obtained at a frequency less than daily are presented first, and tables of "daily values" of specific conductance, pH, water temperature, dissolved oxygen, and suspended sediment then follow in sequence, when these parameters are studied. In the descriptive headings, if the location is identical to that of the discharge gaging station, neither the LOCATION nor the DRAINAGE AREA statements are repeated. The following information, as appropriate, is provided with each continuous-record station. Comments that follow clarify information presented under the various headings of the station description. LOCATION.—See Data Presentation under "Records of Stage and Water Discharge;" same comments apply. DRAINAGE AREA.—See Data Presentation under "Records of Stage and Water Discharge;" same comments apply. PERIOD OF RECORD.—This indicates the periods for which there are published water-quality records for the station. The periods are shown separately for records of parameters measured daily or continuously and those measured less than daily. For those measured daily or continuously, periods of record are given for the parameters individually. INSTRUMENTATION.-Information on instrumentation is given only if a water-quality monitor temperature record, sediment pumping sampler, or other sampling device is in operation at a station. REMARKS.-Remarks provide added information pertinent to the collection, analysis, or computation of the records. COOPERATION.—Records provided by a cooperating organization or obtained for the Geological Survey by a cooperating organization are identified here. EXTREMES.—Maximums and minimums are given only for parameters measured daily or more frequently. None are given for parameters measured weekly or less frequently, because the true maximums or minimums may not have been sampled. Extremes, when given, are provided for both the period of record and for the current water year. REVISIONS.—If errors in published water-quality records are discovered after publication, appropriate updates are made to the Water-Quality File in the U.S. Geological Survey's computerized data system, WATSTORE, and subsequently by monthly transfer of update transactions to the U.S. Environmental Protection Agency's STORET system. Because the usual volume of updates makes it impractical to document individual changes in the State data-report series or elsewhere, potential users of U.S. Geological Survey water-quality data are encouraged to obtain all required data from the appropriate computer file to insure the most recent updates. The surface-water-quality records for partial-record stations and miscellaneous sampling sites are published in separate tables following the table of discharge measurements at miscellaneous sites. No descriptive statements are given for these records. Each station is published with its own station number and name in the regular downstream-order sequence. 27 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1992 Remark Codes The following remark codes may appear with the water-quality data in this report: PRINTED OUTPUT REMARK E Estimated value > Actual value is known to be greater than the value shown < Actual value is known to be less than the value shown K Results based on colony count outside the acceptance range (non-ideal colony count) L Biological organism count less than 0.5 percent (organism may be observed rather than counted) D Biological organism count equal to or greater than 15 percent (dominant) & Biological organism estimated as dominant Records of Ground-Water Levels Only ground-water level data from a basic network of observation wells are published herein. This basic network contains observation wells so located that the most significant data are obtained from the fewest wells in the most important aquifers. Data Collection and Computation Measurements of water levels are made in many types of wells under varying conditions, but the methods of measurement are standardized to the extent possible. The equipment and measuring techniques used at each observation well ensure that measurements at each well are of consistent accuracy and reliability. Each well is identified by means of (1) a 15-digit number that is based on latitude and longitude and (2) a local number that is provided for local needs. See figure 10. Water-level records are obtained from direct measurements with a steel tape or from the graph or punched tape of a water-stage recorder. The water-level measurements in this report are given in feet with reference to land-surface datum (Isd). Land-surface datum is a datum plane that is approximately at land surface at each well. If known, the elevation of the land-surface datum is given in the well description. The height of the measuring point (MP) above or below land-surface datum is given in each well description. Water levels in wells equipped with recording gages are reported for every day and as an instantaneous observation at noon. Water levels are reported to as many significant figures as can be justified by the local conditions. For example, in a measurement of a depth to water of several hundred feet, the error of determining the absolute value of the total depth to water may be a few tenths of a foot, whereas the error in determining the net change of water level between successive measurements may be only a hundredth of a few hundredths of a foot. For lesser depths to water, the accuracy is greater. Accordingly, most measurements reported to a hundredth of a foot, but some are given to a tenth of a foot or a larger unit. 28 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1992 Data Presentation Each well record consists of three parts, the station description, the data table of water levels observed during the water year and a graph of the water levels for the current water year and other selected period. The description of the well is presented first through use of descriptive headings preceding the tabular data. The comments to follow clarify information presented under the various headings of the well description. LOCATION.—This paragraph follows the well-identification number and reports the latitude and longitude (given in degrees, minutes, and seconds); a landline location designation; the hydrologic-unit number; the distance and direction from a geographic point of reference; and the owner's name. AQUIFER.—This entry designates by name (if a name exists) and geologic age the aquifer(s) open to the well. WELL CHARACTERISTICS.-This entry describes the well in terms of depth, diameter, casing depth and/or screened interval, method of construction, use, and additional information such as casing breaks, collapsed screen, and other changes since construction. INSTRUMENTATION.—This paragraph provides information on both the frequency of measurment and the collection method used, allowing the user to better evaluate the reported water-level extremes by knowing whether they are based on weekly, monthly, or some other frequency of measurement. DATUM.—This entry describes both the measuring point and the land-surface elevation at the well. The measuring point is described physically (such as top of collar, notch in top of casing, plug in pump base and so on), and in relation to land surface (such as 1.3 ft above land-surface datum). The elevation of the land-surface datum is- described in feet above mean sea level datum, if available. It is reported with precision depending on the method of determination. REMARKS.—This entry describes factors that may influence the water level in a well or the measurement of the water level. It should identify wells that also are water-quality observation wells, and may be used to acknowledge the assistance of local (non-Survey) observers. PERIOD OF RECORD.—This entry indicates the period for which there are published records for the well. It reports the month and year of the start of publication of water-level records by the U.S. Geological Survey and the words "to current year" if the records are to be continued into the following year. Periods for which water-level records are available, but are not published by the Geological Survey, may be noted. EXTREMES FOR PERIOD OF RECORD.-This entry contains the highest and lowest water levels of the period of published record, with respect to land-surface datum, and the dates of their occurrence. A table of water levels follows the station description for each well. Water levels are reported in feet below land-surface datum and all taped measurements of water level are listed. For wells equipped with recorders, daily values tables are published for the instantaneous water-level observation at noon. The highest and lowest water levels of the water year and their dates of occurrence are shown on a line below the table. Because all values are not published for wells with recorders, the extremes may be values that are not listed in the table. Missing records are indicated by dashes in place of the water level. A hydrograph for a selected period of record follows each water-level table. Records of Ground-Water Quality Records of ground-water quality in this type of report differ from other types of records in that for most sampling sites they consist of only one set of measurements for the water year. The quality of ground water ordinarily changes only slowly; therefore, for most general purposes one annual sampling, or only a few samples taken at infrequent intervals during the year, is sufficient. Frequent measurement of the same constituents is not necessary unless one is concerned with a particular problem, such as monitoring for trends in nitrate concentration. In the special cases where the quality of ground water may change more rapidly, more frequent measurements are made to identify the nature of the changes. 29 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1992 Data Collection and Computation The records of ground-water quality in this report were obtained mostly as a part of special studies in specific areas. Consequently, a number of chemical analyses are presented for some counties but none are presented for others. As a result, the records for this year, by themselves, do not provide a balanced view of ground-water quality Statewide. Such a view can be attained only by considering records for this year in context with similar records obtained for these and other counties in earlier years. Most methods for collecting and analyzing water samples are described in the "U.S. Geological Survey Techniques of Water-Resources Investigations" manuals listed on a following page. The values reported in this type of report represent water-quality conditions at the time of sampling as much as possible, consistent with available sampling techniques and methods of analysis. All samples are obtained by trained personnel. The wells sampled are pumped long enough to assure that the water collected comes directly from the aquifer and has not stood for a long time in the well casing where it would have been exposed to the atmosphere and to the material, possibly metal, comprising the casings. Data Presentation The records of ground-water quality, when available, are published in a section titled QUALITY OF GROUND WATER immediately following the ground-water level records. Data for quality of ground water are listed alphabetically by County, and are identified by well number. The prime identification number for wells sampled is the 15-digit number derived from the latitude-longitude locations. No descriptive statements are given for ground-water-quality records; however, the well number, depth of well, date of sampling, and other pertinent data are given in the table containing the chemical analyses of the ground water. The REMARK codes listed for surface-water-quality records are also applicable to ground-water-quality records. ACCESS TO WATSTORE DATA The U.S. Geological Survey is the principal Federal water-data agency and, as such, collects and disseminates about 70 percent of the water data currently being used by numerous State, local, private, and other Federal agencies to develop and manage our water resources. As part of the U.S. Geological Survey's program of releasing water data to the public, a large-scale computerized system has been developed for the storage and retrieval of water data collected through its activities. The National Water-Data Storage and Retrieval System (WATSTORE) was established in 1972 to provide an effective and efficient means for the processing and maintenance of water data collected through the activities of the U.S. Geological Survey and to facilitate release of the data to the public. A variety of useful products, ranging from data tables to complex statistical analyses such as Log Pearson Type III, can be produced using WATSTORE. The system resides on the central computer facilities of the U.S. Geological Survey at its National Center in Reston, Virginia, and consists of related files and data bases. * Station Header File - Contains descriptive information on over 440,000 sites throughout the United States and its territories where the U.S. Geological Survey collects or has collected data. * Daily Values Files - Contains over 220 million daily values of streamflow, stages, reservoir contents, water temperatures, specific conductances, sediment concentrations, sediment discharges, and ground-water level. * Peak Flow File - Contains approximately 500,000 maximum (peak) streamflow and gage-height values at surface-water sites. * Water-Quality Data - Contains approximately 2 million analyses of water samples that describe the chemical, physical, biological, and radio-chemicals characteristics of both surface and ground water. * Ground-Water Site Inventory Data Base - Contains inventory data for over 900,000 wells, springs, and other sources of ground water. The data includes site location, geohydrologic characteristics, well-construction history, and one-time field measurements such as water temperature. 30 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1992 In 1976, the U.S. Geological Survey opened WATSTORE to the public for direct access. The signing of a Memorandum of Agreement with the Survey is required to obtain direct access to WATSTORE. The system can be accessed either synchronously or asynchronously. The requestor will be expected to pay all computer costs he/she incurs. Direct access may be obtained by contacting: U.S. Geological Survey National Water Data Exchange 421 USGS National Center Reston, Virginia 22092 In addition to providing direct access to WATSTORE, data can be provided in various machine-readable formats on magnetic tape or 5-1/4 inch floppy disk; and, as noted in the introduction, on CD-ROM discs. Beginning with the 1990 water year, all water-data reports will also be available on Compact Disc-Read Only Memory (CD-ROM). All data report published for the current water year for the entire Nation, including Puerto Rico and the Trust Territories, will be reproduced on a single CD-ROM disc. Information about the availability of specific types of data or products, and user charges, can be obtained locally from each of the Water Resources Division's offices. (See address on the back of the title page. A limited number of CD-ROM discs will be available for sale by the Books and Open-File Reports Section, U.S. Geological Survey, Federal Center, Box 25425, Denver, Colorado 80225. DEFINITION OF TERMS Terms related to streamflow, water-quality, and other hydrologic data as used in this report, are defined below. See also the table for converting inch- pound units to the International System of units (SI) on the inside of the back cover. Acre-foot (AC-FT, acre-ft) is the quantity of water required to cover 1 acre to a depth of 1 foot and is equal to about 326,000 gallons or 1,233 cubic meters. Adenosine triphosphate (ATP) is an organic, phosphate-rich, compound important in the transfer of energy in organisms. Its central role in living cells makes it an excellent indicator of the presence of living material in water. A measure of ATP therefore provides a sensitive and rapid estimate of biomass. ATP is reported in micrograms per liter of the original water sample. Algae growth potential (AGP) is the maximum algal dry weight biomass that can be produced in a natural water sample under standardized laboratory conditions. The growth potential is the algal biomass present a stationary phase and is expressed as milligrams dry weight of algae produced per liter of sample. Aquifer is a geologic formation, group of formations, or part of a formation that contains sufficient saturated permeable material to yield significant quantities of water to wells and springs. Artesian means confined and is used to describe a well in which the water level stands above the top of the aquifer, tapped by the well. A flowing artesian well is one in which the water level is above the land surface. Bacteria are microscopic unicellular organisms, typically spherical, rodlike, or spiral and threadlike in shape, often clumped into colonies. Some bacteria cause disease, while others perform an essential role in nature in the recycling of materials; for example, by decomposing organic matter into a form available for reuse by plants. Total coliform bacteria are a particular group of bacteria that are used as indicators of possible sewage pollution. They are characterized as aerobic or facultative anaerobic, gram-negative, nonspore-forming, rod- shaped bacteria which ferment lactose with gas formation within 48 hours at 35°C. In the laboratory these bacteria are defined as all the organisms which produce colonies with a golden-green metallic sheen within 24 hours when incubated at 35°C _+ 1.0°C on M-Endo medium (nutrient medium for bacterial growth). Their concentrations are expressed as number of colonies per 100 mL of sample. Fecal coliform bacteria are bacteria that are present in the intestines or feces of warm-blooded animals. They are often used as indicators of the sanitary quality of the water. In the laboratory they are defined as all organisms which produce blue colonies within 24 hours when incubated at 44.5°C _+ 0.2°C on M-FC medium (nutrient medium for bacterial growth). Their concentrations are expressed as number of colonies per 100 mL of sample. 31 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1992 Fecal streptococcal bacteria are bacteria found also in intestines of warm-blooded animals. Their presence in water is considered to verify fecal pollution. They are characterized as Gram-positive, cocci bacteria which are capable of growth in brain-heart infusion broth. In the laboratory they are defined as all the organisms which produce red or pink colonies within 48 hours at 35°C +_ 1.0°C on KF-streptococcus medium (nutrient medium for bacterial growth). Their concentrations are expressed as number of colonies per 100 mL of sample. Bed material is the unconsolidated material of which a streambed, lake, pond, reservoir, or estuary bottom is composed. Biochemical oxygen demand (BOD) is a measure of the quantity of dissolved oxygen, in milligrams per liter, necessary for the decomposition of organic matter by microorganisms, such as bacteria. Biomass is the amount of living matter present at any given time, expressed as the mass per unit area or volume of habitat. Ash mass is the mass or amount of residue present after the residue from the dry mass determination has been ashed in a muffle furnace at a temperature of 500°C for 1 hour. The ash mass values of zooplankton and phytoplankton are expressed in grams per cubic meter (g/m3), and periphton and benthic organisms in grams per square meter (g/m2). Dry mass refers to the mass of residue present after drying in an oven at 105°C for zooplankton and periphyton, until the mass remains unchanged. This mass represents the total organic matter, ash and sediment, in the sample. Dry-mass values are expressed in the same units as ash mass. Organic mass or volatile mass of the living substance is the difference between the dry mass and the ash mass and represents the actual matter. The organic mass is expressed in the same units as for ash and dry mass. Wet mass is the mass of living matter plus contained water. Bottom material: See Bed material. Cells/volume refers to the number of cells of any organism which is counted by using a microscope and grid or counting cell. Many planktonic organisms are multicelled and are counted according to the number of contained cells per sample, usually milliliters (mL) or liters (L). Chemical oxygen demand (COD) is a measure of the chemically oxidizable material in the water, and furnishes an approximation of the amount of organic and reducing material present. The determined value may correlate with natural water color or with carbonaceous organic pollution from sewage or industrial wastes. Clorophyll refers to the green pigments of plants. Chlorophyll a and b are the two most common green pigments in plants. Color unit is produced by one milligram per liter of platinum in the form of the chloroplatinate ion. Color is expressed in units of the platinum-cobalt scale. Contents is the volume of water in a reservoir or lake. Unless otherwise indicated, volume is computed on the basis of a level pool and does not include bank storage. Control designates a feature downstream from the gage that determines the stage-discharge relation at the gage. This feature may be a natural constriction of the channel, an artificial structure, or a uniform cross section over a long reach of the channel. Control structure as used in this report is a structure on a stream or canal that is used to regulate the flow or stage of the stream or to prevent the intrusion of salt water. 32 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1992 Cubic foot per second (ft3/s) is the rate of discharge representing a volume of 1 cubic foot passing a given point during 1 second and is equivalent to 7.48 gallons per second or 448.8 gallons per minute or 0.02832 cubic meters per second. Cubic foot per second-day (ft3/s/day) is the volume of water represented by a flow of 1 cubic foot per second for 24 hours. It is equivalent to 86,400 cubic feet, approximately 1.9835 acre-feet, about 646,000 gallons, or 2,445 cubic meters. Cubic feet per second per square mile (CFSM) is the average number of cubic feet of water flowing per second from each square mile of area drained, assuming that the runoff is distributed uniformly in time and area. Discharge is the volume of water (or more broadly, volume of fluid plus suspended sediment), that passes a given point within a given period of time. Instantaneous discharge is the discharge at a particular instant of time. Mean discharge (MEAN) is the arithmetic mean of individual daily mean discharges during a specific period. Annual 7-day minimum is the lowest mean discharge for 7 consecutive days for a calendar year or a water year. Note that most low- flow frequency analyses of annual 7-day minimum flows use a climatic year (April 1 - March 31). The date shown in the summary statistics table is the initial date of the 7-day period. (This value should not be confused with the 7-day 10-year low-flow statistic.) Dissolved refers to that material in a representative water sample which passes through a 0.45 um membrane filter. This is a convenient operational definition used by Federal agencies that collect water data. Determinations of "dissolved" constituents are made on subsamples of the filtrate. Dissolved-solids concentration of water is determined either analytically by the "residue-on-evaporation" method, or mathematically by totaling the concentrations of individual constituents reported in a comprehensive chemical analysis. During the analytical determination of dissolved solids, the bicarbonate (generally a major dissolved component of water) is converted to carbonate. Therefore, in the mathematical calculations of dissolved-solids concentration, the bicarbonate value, in milligrams per liter, is multiplied by 0.492 to reflect the change. Diversity index is a numerical expression of evenness of distribution of aquatic organisms. The formula for diversity index is: __ s Where "i is the number of individuals per taxon, n is the total number of individuals, and s is the total number of taxa in the sample of the community. Diversity index values range from zero, when all the organisms in the sample are the same, to some positive number, when some or all of the organisms in the sample are different Drainage area of a stream at a specified location is that area, measured in a horizontal plane, enclosed by a topographic divide from which direct surface runoff from precipitation normally drains by gravity into the stream above the specified point Figures of drainage area given herein include all closed basins, or noncontribution areas, within the area unless otherwise noted. Drainage basin is a part of the surface of the earth that is occupied by a drainage system, which consists of a surface stream or a body of impounded surface water together with all tributary surface streams and bodies of impounded surface water. Gage height (G.H.) is the water-surface elevation referred to some arbitrary gage datum. Gage height is often used interchangeably with the more general term "stage," although gage height is more appropriate when used with a reading on a gage. 33 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1992 Gaging station is a particular site on a stream, canal, lake, or reservoir where systematic observations of hydrologic data are obtained. Ground-water station is a well at which observations of ground-water level are made, either continuously by recorder, or periodically by hand. In addition, various chemical or physical parameters may be obtained, usually on a periodic basis. Hardness of water is a physical-chemical characteristic that is commonly recognized by the increased quantity of soap required to produce lather. It is attributable to the presence of alkaline earths (principally calcium and magnesium) and is expressed as equivalent calcium carbonate (CaCO3). Hydrologic Bench-Mark Network is a network in small drainage basins around the country whose purpose is to provide consistent data on the hydrology, including water quality, and related factors in representative undeveloped watersheds nationwide, and to provide analyses on a continuing basis to compare and contrast conditions observed in basins more obviously affected by the activities of man. Hydrologic unit is a geographic area representing part or all of a surface drainage basin or distinct hydrologic feature as delineated by the Office of Water Data Coordination on the State Hydrologic Unit Maps; each hydrologic unit is identified by an eight-digit number. Land-surface datum (Isd) is a datum plane that is approximately at land surface at each ground-water observation well. Measuring point (MP) is an arbitrary permanent reference point from which the distance to the water surface in a well is measured to obtain the water level. Metamorphic stage refers to the stage of development that an organism exhibits during its transformation from an immature form to an adult form. This developmental process exists for most insects, and the degree of difference from the immature stage to the adult form varies from relatively slight to pronounced, with many intermediates. Examples of metamorphic stages of insects are egg-larva-adult or egg-nymph-adult. Methylene blue active substances (MBAS) are apparent detergents. The determination depends on the formation of a blue color when methylene blue dye reacts with synthetic anionic detergent compounds. Micrograms per gram (ug/g) is a unit expressing the concentration of a chemical element as the mass (micrograms) of the element per unit mass (gram) of material analyzed. Micrograms per liter (UG/L, ug/L) is a unit expressing the concentration of chemical constituents in solution as mass (micrograms) of solute per unit volume (liter) of water. One thousand micrograms per liter is equivalent to one milligram per liter. Milligrams per liter (MG/L, mg/L) is a unit for expressing the concentration of chemical constituents in solution. Milligrams per liter represent the mass of solute per unit volume (liter) of water. Concentration of suspended sediment also is expressed in mg/L, and is based on the mass of sediment per liter of water-sediment mixture. Conversion of chemical concentrations in Mg/L to milliequivalents per liter can be done by using the factors in table 5. 34 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1992 Table 5. Factors for conversion of chemical constituents in milligrams per liter to milliequivalents per liter. Ion Aluminum (Al+3 )*........ Ammonia as NH4+1 ........ Barium (Ba+2) ........... Bicarbonate (HCO3-1) .... Bromide (Br-1) .......... Calcium (Ca+2) .......... Carbonate (CO3-2) ....... Chloride (Cl-1) ......... Chromium (Cr+6 ) *........ Cobalt (Co+2) *.......... Copper (Cu+2) *.......... Cyanide (CN-1) .......... Fluoride (F-l) .......... Hydrogen (H+l) .......... Hydroxide (OH-1 )........ Multiply by 0.11119 .05544 .01456 .01639 .01251 .04990 .03333 .02821 .11539 .03394 .03148 .03844 .05264 .99209 .05880 Ion Iodide (1-1) ......... Iron (Fe+3) .......... Lead (Pb+2) .......... Lithium (Li+1) ....... Magnesium (Mg+2) ..... Manganese (Mn+2 )*.... Nickel (Ni+2) ........ Nitrate (N03-1) ...... Nitrite (N02-1) ...... Phosphate (PO4-3) .... Potassium (K+l) ...... Sodium (NA+1) ........ Strontium (Sr+2) ..... Sulfate (S04-2) ...... Zinc (Zn+2) *......... Multiply by 0.00788 .05372 .00965 .14411 .08226 .03640 .03406 .01613 .02174 .03159 .02557 .04350 .02283 .02082 .03060 Constituent reported in micrograms per liter; multiply by factor and divide results by 1,000, National Stream Quality Accounting Network (NASQAN) is a nationwide data-collection network designed by the U.S. Geological Survey to meet many of the information needs of government agencies and other groups involved in natural or regional water-quality planning and management. The 500 or so sites in NASQAN are generally located at the downstream ends of hydrologic accounting units designated by the U.S. Geological Survey office of Water Data Coordination in consultation with the Water Resources Council. The objectives of NASQAN are (1) to obtain information on the quality and quantity of water moving within and from the United States through a systematic and uniform process of data collection, summarization, analysis, and reporting such that the data may be used for, (2) description of the areal variability of water quality in the Nation's rivers through analysis of description of the areal variability of water quality in the Nation's rivers through analysis of data from this and other programs, (3) detection of changes or trends with time in the pattern of occurrence of water-quality characteristics, and (4) providing a nationally consistent data base useful for water-quality assessment and hydrologic research. National Trends Network (NTN) is a network for sampling atmospheric deposition in the United States. The purpose of the network is to determine the variability, both in location and in time, of the composition of atmospheric deposition, which includes snow, rain, dust particles, aerosols, and gases. The core from which the NTN was built was the already-existing deposition-monitoring network of the National Atmospheric Deposition Program (NADP). Organism is any living entity. Organism count/area refers to the number of organisms collected and enumerated in a sample and adjusted to the number per unit area habitat, usually square meters (m2), acres, or hectare. Periphyton, benthic organisms, and macrophytes are expressed in these terms. Organism count/volume refers to the number of organisms collected and enumei ated in a sample and adjusted to the number per sample volume, usually milliliters (mL) or liters (L). Numbers of planktonic organisms can be expressed in these terms. Total organism count is the total number of organisms collected and enumerated in any particular sample. Parameter Code is a 5-digit number used in the U.S. Geological Survey computerized data system, WATSTORE, to uniquely identify a specific constituent. The codes used in WATSTORE are the same as those used in the U.S. Environmental Protection Agency data system, STORET. The Environmental Protection Agency assigns and approves all requests for new codes. Partial-record station is a particular site where limited streamflow and/or water-quality data are collected systematically over a period of years for use in hydrologic analyses. 35 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1992 Particle-size is the diameter, in millimeters (mm), of a particle determined by either sieve or sedimentation methods. Sedimentation methods (pipet, bottom-withdrawal tube, visual-accumulation tube) determine fall diameter of particles in either distilled water (chemically dispersed) or in native water (the river water at the time and point of sampling). Particle-size classification used in this report agrees with recommendations made by the American Geophysical Union Subcommittee on Sediment Terminology. The classification is as follows: Classification Size (mm) Method of analysis Clay...... 0.00024 - 0.004 Sedimentation Silt...... .004 - .062 Sedimentation Sand...... .062 - 2.0 Sedimentation or sieve Gravel.... 2.0 - 64.0 Sieve The particle-size distributions given in this report are not necessarily representative of all particles in transport in the stream. Most of the organic matter is removed and the sample is subjected to mechanical and chemical dispersion before analysis in distilled water. Chemical dispersion is not used for native water analysis. Percent composition is a unit for expressing the ratio of a particular part of a sample or population to the total sample or population, in terms of types, numbers, mass or volume. Periphyton is the assemblage of microorganisms attached to and living upon submerged solid surfaces. While primarily consisting of algae, they also include bacteria, fungi, protozoa, rotifers, and other small organisms. Pesticides are chemical compounds used to control undesirable organisms. Major categories of pesticides include insecticides, miticides, fungicides, herbicides, and rodenticides. Picocurie (PC, pCi) is one trillionth (1 X 10-12) of the amount of ratioactivity represented by a curie (Ci). A curie is the amount of radioactivity that yields 3.7 x 10'° radioactive disintegrations per second. A picocurie yields 2.22 dpm (disintegrations per minute). Plankton is the community of suspended, floating, or weakly swimming organisms that live in the open water of lakes and rivers. Phytoplankton is the plant part of the plankton. They are usually microscopic and their movement is subject to the water currents. Phytoplankton growth is dependent upon solar radiation and nutrient substances. Because they are able to incorporate as well as release materials to the surrounding water, the phytoplankton have a profound effect upon the quality of the water. They are the primary food producers in the aquatic environment, and are commonly known as algae. Blue-green algae are a group of phytoplankton organisms having a blue pigment, in addition to the green pigment called chlorophyll. Blue-green algae often cause nuisance conditions in water. Diatoms are the unicellular or colonial algae having a siliceous shell. Their concentrations are expressed as number of cells per milliliter (cells/mL) of sample. Green algae have chlorophyll pigments similar in color to thos of higher green plants. Some forms produce algae mats or floating "moss" in lakes. Their concentrations are expressed as number of cells per milliliter (cells/mL) of sample. Zooplankton is the animal part of the plankton. Zooplankton are capable of extensive movements within the water column and are often large enough to be seen with the unaided eye. Zooplankton are secondary consumers feeding upon bacteria, phytoplankton, and detritus. Because they are the grazers in the aquatic environment, the Zooplankton are a vital part of the aquatic food web. The Zooplankton community is dominated by small crustaceans and rotifers. 36 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1992 Primary productivity is a measure of the rate at which new organic matter is formed and accumulated through photosynthetic and chemosynthetic activity of producer organisms (chiefly, green plants). The rate of primary production is estimated by measuring the amount of oxygen released (oxygen method) or the amount of carbon assimilated by the plants (carbon method). Milligrams of carbon per area or volume per unit time [mg C/(m2.time)] for periphyton and macrophytes and [mg C/(m3.time)1 for phytoplankton are units for expressing primary productivity. They define the amount of carbon dioxide consumed as measured by radioactive carbon (carbon 14). The carbon 14 method is of greater sensitivity than the oxygen light and dark bottle method, and is preferred for use in unenriched waters. Unit time may be either hour or day, depending on the incubation period. Milligrams of oxygen per area or volume per unit time [mgO / (m2.time)1 for periphvton and macrophytes and fmgO /(m3.time)1 for phytoplankton are the units for expressing primary productivity. They define production and respiration rates as estimated from changes in the measured dissolved-oxygen concentration. The oxygen light and dark bottle method is preferred if the rate of primary production is sufficient for accurate measurements to be made within 24 hours. Unit time may be either the hour or day, depending on the incubation period. Polychlorinated biphenyls (PCBs) are industrial chemicals that are mixtures of chlorinated biphenyl compounds having various percentages of chlorine. They are similar in structure to organochlorine insecticides. Radiochemical program is a network of regularly sampled water-quality stations where samples are collected to be analyzed for radioisotypes. The streams that are sampled represent major drainage basins in the conterminous United States. Recoverable from bottom material is the amount of a given constituent that is in solution after a representative sample of bottom material has been digested by a method (usually using an acid or mixture of acids) that results in dissolution of readily soluble substances. Complete dissolution of all bottom material is not achieved by the digestion treatment and thus the determination represents less than the total amount (that is, less than 95 percent) of the constituent in the sample. To achieve comparability of analytical data, equivalent digestion procedures would be required of all laboratories performing such analyses because different digestion procedures are likely to produce different analytical results. Return period is the average time interval between occurrences of a hydrological event of a given or greater magnitude, usually expressed in years. May also be called recurrence interval. Runoff in inches (IN, in) shows the depth to which the drainage area would be covered if all the runoff for a given time period were uniformly distributed on it. Sediment is solid material that originates mostly from disintegrated rocks and i* transported by, suspended in, or deposited from water; it includes chemical and biochemical precipitates and decomposed organic material, such as humus. The quantity, characteristics, and cause of the occurrence of sediment in streams are inrVaenced by environmental factors. Some major factors are degree of slope, length of slope, soil characteristics, land usage, and quantity and intensity of precipitation. Bed load is the sediment that is transported in a stream by rolling, sliding, or skipping along the bed and very close to it. In this report, bed load is considered to consist of particles in transit within 0.25 ft of the streambed. Bed load discharge (tons per day) is the quantity of bed load measured by dry weight that moves past a section as bed load in a given time. Suspended sediment is the sediment that at any given time is maintained in suspension by the upward components of turbulent currents or that exists in suspension as a colloid. Suspended-sediment concentration is the velocity-weighted concentration of suspended sediment in the sampled zone (from the water surface to a point approximately 0.3 ft above the bed) expressed as milligrams of dry sediment per liter of water-sediment mixture (mg/L). 37 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1992 Mean concentration is the time-weighted concentration of suspended sediment passing a stream section during a 24-hour day. Suspended-sediment discharge (tons/day) is the rate at which dry mass of sediment passes a section of a stream or is the quantity of sediment, as measured by dry mass or volume, that passes a section in a given time. It is calculated in units of tons per day as follows: concentrations (mg/L) x discharge (ft3/s) x 0.0027. Suspended-sediment load is a general term that refers to material in suspension. It is not synonymous with either discharge or concentration. Total sediment discharge (tons/day) is the sum of the suspended-sediment discharge and the bed-load discharge. It is the total quantity of sediment, as measured by dry mass or volume, that passes a section during a given time. Total-sediment load or total load is a term which refers to the total sediment (bed load plus suspended- sediment load) that is in transport. It is not synonymous with total-sediment discharge. 7-day 10-year low flow (7Q10) is the discharge at the 10-year recurrence interval taken from a frequency curve of annual values of the lowest mean discharge for 7 consecutive days (the 7-day low flow). Sodium-adsorption-ratio (SAR) is the expression of relative activity of sodium ions in exchange reactions within soil and is an index of sodium or alkali hazard to the soil. Waters range in respect to sodium hazard from those which can be used for irrigation on almost all soils to those which are generally unsatisfactory for irrigation. Solute is any substance that is dissolved in water. Specific conductance is a measure of the ability of a water to conduct an electric current. It is expressed in microsiemens per centimeter at 25°C. Specific conductance is related to the type and concentration of ions in solution and can be used for approximating the dissolved-solids content of the water. Commonly, the concentration of dissolved solids (in milligrams per liter) is about 65 percent of the specific conductance (in micromhos). This relation is not constant from stream to stream, and it may vary in the same source with changes in the composition of the water. Stage-discharge relation is the relation between gage height (stage) and volume of water per unit of time, flowing in a channel. Streamflow is the discharge that occurs in a natural channel. Although the term "discharge" can be applied to the flow of a canal, the word "streamflow" uniquely describes the discharge in a surface stream course. The term "streamflow" is more general than "runoff as streamflow may be applied to discharge whether or not it is affected by diversion or regulation. Substrate is the physical surface upon which an organism lives. Natural substrate refers to any naturally occurring emersed or submersed solid surface, such as a rock or tree, upon which an organism lives. Artificial substrate is a device which is purposely placed in a stream or lake for colonization of organisms. The artificial substrate simplifies the community structure by standardizing the substrate from which each sample is taken. Examples of artificial substrates are basket samplers (made of wire cages filled with clean streamside rocks) and multiplate samplers (made of hardboard) for benthic organism collection, and plexiglass strips for periphyton. Surface area of a lake is that area outlined on the latest U.S.G.S. topographic map as the boundary of the lake and measured by a planimeter in acres. In localities not covered by topographic maps, the areas are computed from the best maps available at the time planimetered. All areas shown are those for the stage when the planimetered map was made. Surficial bed material is that part (0.1 to 0.2 ft) of the bed material that is sampled using U.S. Series Bed-Material Samplers. 3d WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1992 Suspended (as used in tables of chemical analyses) refers to the amount (concentration) of the total concentration in a water-sediment mixture. It is associated with the material retained on a 0.45-micrometer filter. Suspended, recoverable is the amount of a given constituent that is in solution after the part of a representative water- suspended sediment sample that is retained on a 0.45 um membrane filter has been digested by a method (usually using a dilute acid solution) that results in dissolution of only readily soluble substances. Complete dissolution of all the participate matter is not achieved by the digestion treatment and thus the determination represents something less than the "total" amount (that is, less than 95 percent) of the constituent present in the sample. To achieve comparability of analytical data, equivalent digestion procedures are required of all laboratories performing such analyses because different digestion procedures are likely to produce different analytical results. Determinations of "suspended, recoverable" constituents are made either by analyzing portions of the material collected on the filter or, more commonly, by difference, based on determinations of (1) dissolved and (2) total recoverable concentrations of the constituent. Suspended, total is the total amount of a given constituent in the part of representative water-suspended sediment sample that is retained on a 0.45 um membrane filter. This term is used only when the analytical procedure assures measurement of at least 95 percent of the constituent determined. A knowledge of the expected form of the constituent in the sample, as well as the analytical methodology used, is required to determine when the results should be reported as "suspended, total." Determinations of "suspended, total" constituents are made either by analyzing portions of the material collected on the filter or, more commonly, by difference, based on determinations of (1) dissolved and (2) total concentrations of the constituent. Taxonomy is the division of biology concerned with the classification and naming of organisms. The classification of organisms is based upon a hierarchial scheme beginning with Kingdom and ending with Species at the base. The higher the classification level, the fewer features the organisms have in common. For example, the taxonomy of a particular mayfly, Hexagenia limbata, is the following: Kingdom.....................Animal Phylum........................Arthopoda Class...........................Insecta Order...........................Ephemeroptera Family.........................Ephemeridae Genus..........................Hexagenia Species........................Hexagenia limbata Thermograph is an instrument that continuously records variations of temperature on a chart. The more general term "temperature recorder" is used in the table heading and refers to any instrument that records temperature whether on a chart, a tape, or any other medium. Time-weighted average is computed by multiplying the number of days in the sampling period by the concentrations of individual constituents for the corresponding period and dividing the sum of the products by the total number of days. A time-weighted average represents the composition of water that would be contained in a vessel or reservoir that had received equal quantities of water from the stream each day for the year. Tons per acre-foot indicates the dry mass of dissolved solids in 1 acre-foot of water. It is computed by multiplying the concentration of the constituent, in milligrams per liter by 0.00136. Tons per day (T/DAY) is the quantity of a substance in solution or suspension that passes a stream section during a 24-hour period. 39 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1992 Total is the total amount of a given constituent in a representative water-suspended sediment sample, regardless of the constituent's physical or chemical form. This term is used only when the analytical procedure assures measurement of at least 95 percent of the constituent present in both the dissolved and suspended phases of the sample. A knowledge of the expected form of the constituent in the sample, as well as the analytical methodology used, is required to judge when the results should be reported as "total." (Note that the word "total" does double duty here, indicating both that the sample consists of a water-suspended sediment mixture and that the analytical method determined all of the constituent in the sample.) Total discharge is the total quantity of any individual constituent, as measured by dry mass or volume, that passes through a stream cross-section per unit of time. This term needs to be qualified, such as "total sediment discharge," "total chloride discharge," and so on. Total, recoverable is the amount of a given constituent that is in solution after a representative water-suspended sediment sample has been digested by a method (usually using a dilute acid solution) that results in dissolution of only readily soluble substances. Complete dissolution of all paniculate matter is not achieved by the digestion treatment, and thus the determination represents something less than the "total" amount (that is, less than 95 percent) of the constituent present in the dissolved and suspended phases of the sample. To achieve comparability of analytical data, equivalent digestion procedures are required of all laboratories performing such analyses, because different digestion procedures are likely to produce different analytical results. Tritium Network is a network of stations which has been established to provide baseline information on the occurrence of tritium in the Nation's surface waters. In addition to the surface-water stations in the network, tritium data are also obtained at a number of precipitations stations. The purpose of the precipitation stations is to provide an estimate sufficient for hydrologic studies of the tritium input to the United States. Water year in Geological Survey reports dealing with surface water supply is the 12-month period, October 1 through September 30. The water year is designated by the calendar year in which it ends and which includes 9 of the 12 months. Thus, the year ending September 30, 1980, is called the "1980 water year." WDR is used as an abbreviation for "Water-Data Report" in the REVISED RECORDS paragraph to refer to State annual hydrologic-data reports (WRD was used as an abbreviation for "Water-Resources Data" in reports published prior to 1976). Weighted average is used in this report to indicate discharge-weighted average. It is computed by multiplying the discharge for a sampling period by the concentrations of individual constituents for the corresponding period and dividing the sum of the products by the sum of the discharges. A discharge- weighted average approximates the composition of water that would be found in a reservoir containing all the water passing a given location during the water year after thorough mixing in the reservoir. WSP is used as an abbreviation for "Water-Supply Paper" in references to previously published reports. 40 PUBLICATIONS ON TECHNIQUES OF WATER-RESOURCES INVESTIGATIONS The U.S. Geological Survey publishes a series of manuals describing procedures for planning and con- ducting specialized work in water-resources investigations. The material is grouped under major subject headings cafled books and is further divided into sections and chapters. For example, Section A of Book 3 (Applications of Hydraulics) pertains to surface water. The chapter, the unit of publication, is limited to a narrow field of subject matter. This format permits flexibility in revision and publication as the need arises. The reports listed below are for sale by the U.S. Geological Survey, Books and Open-File Reports Section, Federal Center, Box 25425, Denver, Colorado 80225 (authorized agent of the Superintendent of Docu- ments, Government Printing Office). Prepayment is required. Remittance should be sent by check or money order payable to the U.S. Geological Survey. Prices are not included because they are subject to change. Current prices can be obtained by writing to the above address. When ordering or inquiring about prices for any of these publications, please give the title, book number, chapter number, and "U.S. Geolog- ical Survey Techniques of Water-Resources Investigations." 1-D1. Water temperature-influential factors, field measurement, and data presentation, by H. H. Stevens, Jr., J. F. Ficken, and G. F. Smoot: USGS--TWRI Book 1, Chapter D1. 1975. 65 pages. 1-D2. Guidelines for collection and field analysis of ground-water samples for selected unstable constituents, by W. W. Wood: USGS-TWRI Book 1, Chapter D2.1976. 24 pages. 2-D1. Application of surface geophysics to ground-water investigations, by A. A. R. Zohdy, G. P. Eaton, and D. R. Mabey: USGS-TWRI Book 2, Chapter D1.1974.116 pages. 2-D2. Application of seismic-refraction techniques to hydrologic studies, by F. P. Haeni: USGS-TWRI Book 2, Chapter D2.1988. 86 pages. 2-E1. Application of borehole geophysics to water-resources investigations, by W. S. Keys and L M. McCary: USGS-TWRI Book 2, Chapter E1.1971.126 pages. 2-E2. Borehole geophysics applied to ground-water investigations, by W. S. Keys: USGS-TWRI Book 2, Chapter E2.1990.150 pages. 2-F1. Application of drilling, coring, and sampling techniques to test holes and wells, by Eugene Shuter and W. E. Teasdale: USGS--TWRI Book 2, Chapter F1.1989. 97 pages. 3-A1. General field and office procedures for indirect discharge measurements, by M. A. Benson and Tate Dalrymple: USGS--TWRI Book 3, Chapter A1.1967. 30 pages. 3-A2. Measurement of peak discharge by the slope-area method, by Tate Dalrymple and M. A. Benson: USGS--TWRI Book 3, Chapter A2. 1967.12 pages. 3-A3. Measurement of peak discharge at culverts by indirect methods, by G. L. Bodhaine: USGS-TWRI Book 3, Chapter A3.1968. 60 pages. 3-A4. Measurement of peak discharge at width contractions by indirect methods, by H. F. Matthai: USGS-TWRI Book 3, Chapter A4.1967. 44 pages. 3-A5. Measurement of peak discharge at dams by indirect methods, by Harry Hulsing: USGS-TWRI Book 3. Chapter A5.1967. 29 pages. 3-A6. General procedure for gaging streams, by R. W. Carter and Jacob Davidian: USGS-TWRI Book 3, Chapter A6.1968.13 pages. 3-A7. Stage measurements at gaging stations, by T. J. Buchanan and W. P. Somers: USGS-TWRI Book 3, Chapter A7.1968. 28 pages. 3-A8. Discharge measurements at gaging stations, by T. J. Buchanan and W. P. Somers: USGS-TWRI Book 3, Chapter A8.1969. 65 pages. 3-A9. Measurement of time of travel in streams by dye tracing, by F. A. Kilpatrick and J. F. Wilson, Jr.: USGS-TWRI Book 3, Chapter A9. 1989. 27 pages. 41 PUBLICATIONS ON TECHNIQUES OF WATER-RESOURCES INVESTIGATIONS-Continued 3-AIO. Discharge ratings at gaging stations, by E. J. Kennedy: USGS--TWRI Book 3, Chapter A10.1984. 59 pages. 3-A11. Measurement of discharge by moving-boat method, by G. F. Smoot and C. E. Novak: USGS-- TWRI Book 3, Chapter A11. 1969. 22 pages. 3-A12. Fluorometric procedures for dye tracing, by J. F. Wilson, Jr., E. D. Cobb, and F. A. Kilpatrick: USGS- -TWRl Book 3, Chapter A12.1986. 41 pages. 3-A13. Computation of continuous records of streamflow, by E. J. Kennedy: USGS--TWRI Book 3, Chapter A13.1983. 53 pages. 3-A14. Use of flumes in measuring discharge, by F. A. Kilpatrick and V. R. Schneider: USGS-TWRI Book 3, Chapter A14.1983. 46 pages. 3-A15. Computation of water-surface profiles in open channels, by Jacob Davidian: USGS-TWRI Book 3, Chapter A15.1984.48 pages. 3-A16. Measurement of discharge using tracers, by F. A. Kilpatrick and E. D. Cobb: USGS-TWRI Book 3, Chapter A16.1985. 52 pages. 3-A17. Acoustic velocity meter systems, by Antonius Laenen: USGS-TWRI Book 3, Chapter A17.1985. 38 pages. 3-A18. Determination of stream reaeration coefficients by use of tracers, by F. A. KHpatrick, R. E. Rathburn, Nobuhiro Yotsukura, G. W. Parker, and L L. DeLong: USGS-TWRI Book 3, Chapter A18.1989. 52 pages. 3-A19. Levels of streamflow gaging stations, by E.J. Kennedy: USGS-TWRI Book 3, Chapter A19.1990. 27 pages. 3-B1. Aquifer-test design, observation, and data analysis, by R. W. Stallman: USGS-TWRI Book 3, Chapter B1.1971. 26 pages. 3-B2. Introduction to ground-water hydraulics, a programmed text for self-instruction, by G. D. Bennett: USGS- TWRl Book 3, Chapter B2.1976.172 pages. 3-B3. Type curves for selected problems of flow to wells in confined aquifers, by J. E. Reed: USGS- TWRI Book 3, Chapter B3.1980.106 pages. 3-B4. Regression modeling of ground-water flow, by R. L. Cooley and R. L. Naff: USGS-TWRI Book 3, Chapter B4.1990. 232 pages. 3-B5. Definition of boundary and initial conditions in the analysis of saturated ground-water flow systems-An introduction, by O. L. Franke, T. E. Reilly, and G. D. Bennett: USGS-TWRI Book 3, Chapter B5.1987.15 pages. 3-B6. The principle of superposition and its application in ground-water hydraulics, by T. E. Reilly, O. L. Franke, and G. D. Bennett: USGS-TWRI Book 3, Chapter B6.1987. 28 pages. 3-B7. Analytical solutions for one-, two-, and three-dimensional solute transport in ground-water systems with uniform flow, by E. J. Wexler: USGS-TWRI Book 3, Chapter B7.1992.90 pages. 3-C1. Fluvial sediment concepts, by H. P. Guy: USGS-TWRI Book 3, Chapter C1.1970. 55 pages. 3-C2. Field methods for measurement of fluvial sediment, by H. P. Guy and V. W. Norman: USGS-TWRI Book 3, Chapter C2.1970. 59 pages. 3-C3. Computation of fluvial-sediment discharge, by George Porterfield: USGS-TWRI Book 3, Chapter C3.1972. 66 pages. 4-A1. Some statistical tools in hydrology, by H. C. Riggs: USGS-TWRI Book 4, Chapter A1.1968. 39 pages. 42 PUBLICATIONS ON TECHNIQUES OF WATER-RESOURCES INVESTIGATlONS-Continued 4-A2. Frequency curves, by H. C. Riggs: USGS--TWRI Book 4, Chapter A2. 1968. 15 pages. 4-B1. Low-flow investigations, by H. C. Riggs: USGS--TWRI Book 4, Chapter B1.1972. 18 pages. 4-B2. Storage analyses for water supply, by H. C. Riggs and C. H. Hardison: USGS--TWRI Book 4, Chapter B2.1973. 20 pages. 4-B3. Regional analyses of streamflow characteristics, by H. C. Riggs: USGS--TWRI Book 4, Chapter B3.1973.15 pages. 4-D1. Computation of rate and volume of stream depletion by wells, by C. T. Jenkins: USGS--TWRI Book 4, Chapter D1.1970.17 pages. 5-A1. Methods for determination of inorganic substances in water and fluvial sediments, by M. J. Fishman and L C. Friedman: USGS--TWRI Book 5, Chapter A1.1989. 545 pages. 5-A2. Determination of minor elements in water by emission spectroscopy, by P. R. Barnett and E. C. Mallory, Jr.: USGS--TWRI Book 5, Chapter A2.1971. 31 pages. 5-A3. Methods for the determination of organic substances in water and fluvial sediments, edited by R. L. Wershaw, M. J. Fishman, R. R. Grabbe, and L. E. Lowe: USGS--TWRI Book 5, Chapter A3. 1987. 80 pages. 5-A4. Methods for collection and analysis of aquatic biological and microbiological samples, by L. J. Britton and P. E. Greeson, editors: USGS--TWRI Book 5, Chapter A4.1989.363 pages. 5-A5. Methods for determination of radioactive substances in water and fluvial sediments, by L. L. Thatcher, V. J. Janzer, and K. W. Edwards: USGS--TWRI Book 5, Chapter A5.1977. 95 pages. 5-A6. Quality assurance practices for the chemical and biological analyses of water and fluvial sediments, by L. C. Friedman and D. E. Erdmann: USGS--TWRI Book 5, Chapter A6.1982.181 pages. 5-C1. Laboratory theory and methods for sediment analysis, by H. P. Guy: USGS-TWRI Book 5, Chapter C1. 1969. 58 pages. 6-A1. A modular three-dimensional finite-difference ground-water flow model, by M. G. McDonald and A. W. Harbaugh: USGS--TWRI Book 6, Chapter A1.1988. 586 pages. 6-A2. Documentation of a computer program to simulate aquifer-system compaction using the modular finite-difference ground-water flow model, by S. A. Leake and D. E. Prudic: USGS--TWRI Book 6, Chapter A2.1991. 68 pages. 7-C1. Finite difference model for aquifer simulation in two dimensions with results of numerical experiments, by P. C. Trescott, G. F. Pinder, and S. P. Larson: USGS--TWRI Book 7, Chapter C1. 1976.116 pages. 7-C2. Computer model of two-dimensional solute transport and dispersion in ground water, by L. F. Konikow and J. D. Bredehoeft: USGS--TWRI Book 7, Chapter C2.1978. 90 pages. 7-C3. A model for simulation of flow in singular and interconnected channels, by R. W. Schaff rannek, R. A. Baltzer, and D. E. Goldberg: USGS--TWRI Book 7, Chapter C3.1981.110 pages. 8-A1. Methods of measuring water levels in deep wells, by M. S. Garber and F. C. Koopman: USGS-- TWRI Book 8, Chapter A1.1968. 23 pages. 8-A2. Installation and service manual for U.S. Geological Survey manometers, by J. D. Craig: USGS-- TWRI Book 8, Chapter A2.1983. 57 pages. 8-B2. Calibration and maintenance of vertical-axis type current meters, by G. F. Smoot and C. E. Novak: USGS--TWRI Books, Chapter B2.1968.15 pages. 43 Surface and Quality-of-Water Records for Puerto Rico 44 THIS PAGE WAS LEFT BLANK INTENTIONALLY 45 ATLANTIC OCEAN R.e CaUD'.AiH v > ;--_ ,1 * »ai"» •) v ; \ ); ^-4 X- V y/i \, at \ a EXPLANATION A 0105 SURFACE-WATER STATION AND NUMBER Y°™5 QUALITY-OF-WATER STATION AND NUMBER Voio72o QUALITY-OF-WATER PARTIAL RECORD STATION AND NUMBER • 165 WELL AND WELL NUMBER _»Jlv»«,;f / / 0 1 2 3 4 5 6 KILOMETERS 234 MILES Figure 13.--Rio Guajataca basin. 4O RIO GUAJATACA BASIN 50010500 RIO GUAJATACA AT LARES, PR LOCATION.--Lat 18°18'01", long 66°52'24", Hydrologic Unit 21010001 at bridge on Highway 111, 0.1 mi (0.2 km) upstream from Quebrada Anon, and 0.4 mi (0.6 km) east of Lares. DRAINAGE AREA.--3.16 mi* (8.18 km9 ). HATER-DISCHARGE RECORDS PERIOD OF RECORD.--February 1959 to February 1962 (annual low-flow measurements only), January 1963 to April 1969 (monthly measurements only), May 1969 to December 1970 (February to May 1971 and March 1974 to November 1989, monthly measurements only), December 1989 to current year. GAGE.—Hater-stage recorder and crest-stage gage. Elevation of gage is 935 ft (285 m), from topographic map. REMARKS.--Records poor. Gage-height and precipitation satellite telemetry at station. Small diversion above station for sewage treatment plant; effluent re-enters stream below station. DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES NOV DEC JAN MAR APR MAY JUN AUG 1 11 23 2 12 17 3 11 14 4 9.6 12 5 9.0 12 6 8.6 11 7 8.1 10 8 49 9.4 9 14 9.0 10 12 9.1 11 9.4 8.2 12 9.3 7.7 13 26 7.7 14 11 7.2 15 9.1 7.2 16 9.2 5.6 17 7.8 5.6 18 44 5.2 19 91 e4.4 20 32 e4.2 21 18 e4.0 22 17 e3.8 23 13 e3.5 24 12 e3.3 25 18 e3.1 26 12 e3.3 27 11 e2.8 28 11 2.6 29 10 2.5 30 18 2.6 31 99 --- TOTAL 632.1 221.0 MEAN 20.4 7.37 MAX 99 23 MIN 7.8 2.5 AC-FT 1250 438 CFSM 6.45 2.33 IN. 7.44 2.60 e Estimated 3.7 2.8 2.1 1.8 1.9 1.8 1.7 1.6 1.8 el. 5 el. 4 el. 3 el. 2 el. 2 el.l el.l el.O el.O e.96 el. 7 el. 5 .97 .95 .91 .89 .87 .84 .84 .84 .84 .82 42.93 1.38 3.7 .82 85 .44 .51 STATISTICS OF MONTHLY MEAN DATA MEAN 19.9 10.6 MAX 33.7 16.7 (HY) 1991 1971 MIN 11.9 6.51 (HY) 1971 1991 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 3.78 7.31 1971 1.35 1991 FOR e.85 e.82 e.81 e.80 el.O e2.4 el.O e.83 e.81 e.82 el. 3 el.l el.O e.96 e.94 el.O el.O el. 3 el.O el.l el.O el.O e.98 e.94 el.O el.O e.96 e.97 e.97 e.96 e.97 31.59 1.02 2.4 .80 63 .32 .37 FOR HATER 2.73 6.83 1971 .66 1991 el.O el.l el.l el.l el.O el.O e.96 e.93 e.89 e.90 e.89 e.90 e.90 e.90 e.94 e.90 e.94 e.91 el.O el.O e.96 e.90 e.88 e.88 e.88 e.87 e.84 e.83 e.80 ___ —— 27.10 .93 1.1 .80 54 .30 .32 YEARS 1969 2.31 5.37 1971 .93 1992 e.78 e.77 e.76 e.74 e.80 el. 4 e2.0 e.86 e.74 el. 2 e.72 e.66 e.66 e.64 e.64 e.76 e.81 e.69 e.68 e.64 e.64 e.64 e.61 e2.0 e2.3 el.O e2.5 el5 e5.0 e2.5 el. 5 50.64 1.63 15 .61 100 .52 .60 - 1992 2.50 6.38 1971 1.01 1970 1991 CALENDAR YEAR 2551. 6. 104 f 5060 2. 30. 15 3. . 94 99 May 20 47 Jan 13 51 Jan 9 21 04 1 83 el.l .92 .86 .86 .80 .98 .88 el.O el. 8 e3.0 e2.2 el. 6 el. 3 el. 2 e2.0 e3.9 e3.0 e6.2 e3.2 e2.2 el. 8 el. 4 el. 3 el. 3 el. 2 el.l el.O e.96 e.94 el.O --- 51.00 1.70 6.2 .80 101 .54 .60 el. 5 el. 2 el.O el.O el.O e.93 e.91 e.84 e.94 e2.8 e9.8 e4.5 e2.8 e2.1 el. 9 e2.3 e2.1 e6.4 e3.6 e7.0 e4.6 e!3 elO e5.8 e6.6 e3.1 e2.6 e4.6 e4.3 e6.0 e4.5 119.72 3.86 13 .84 237 1.22 1.41 e2.8 e2.1 el. 7 el. 6 e4.2 e5.8 e!3 e5.6 e4.8 e3.7 e3.5 e3.5 e3.3 e3.0 e2.8 e2.7 e2.7 e2.5 e2.4 e2.3 e2.3 e2.2 e2.3 e2.1 e2.1 e2.1 e2.2 e2.1 e2.0 el. 9 --- 95.3 3.18 13 1.6 189 1.01 1.12 e2.0 e2.5 e2.6 e2.3 e2.0 el. 9 el. 9 e2.1 el. 9 el. 8 e2.5 el. 9 el. 7 el. 6 el. 5 el. 5 e4.2 e3.5 e2.6 e3.6 e3.2 e2.0 el. 7 e2.2 el. 9 e2.2 e3.4 e2.1 el. 6 e3.4 e3.2 72.5 2.34 4.2 1.5 144 .74 .85 e2.3 e2.0 el. 8 el. 8 e6.0 e5.4 e3.2 e2.4 e2.3 e2.1 el. 9 e2.8 e5.2 e2.7 e2.2 e2.1 e2.0 e2.0 e2.1 e2.2 e2.5 e4.0 e4.8 elO e9.4 e7.0 e4.8 e4.0 e3.7 e3.6 e8.0 116.3 3.75 10 1.8 231 1.19 1.37 e!8 e!6 e!5 7.1 5.6 7.1 5.9 19 8.1 14 8.5 5.7 5.1 4.9 4.4 6.3 4.8 6.9 6.2 16 4.9 5.5 11 5.6 6.6 4.9 4.1 3.9 3.5 24 __- 258.6 8.62 24 3.5 513 2.73 3.04 , BY HATER YEAR (WY) 3.63 6.34 1971 1.31 1970 FOR 1992 1718 4 99 2870 17 3410 1 20 11 2 9.13 12.3 1991 3.86 1992 HATER YEAR .78 .70 Oct 31 .61 Mar 23 .67 Mar 17 Oct 19 .31 Oct 19 .49 .23 .1 .86 6.98 9.73 1970 3.18 1992 4.47 9.85 1969 2.03 1990 HATER 6 8 4 216 5300 21 4580 2 27 14 3 5.34 9.88 1991 3.34 1970 YEARS 1969 .33 .05 .70 .47 .51 .30 .00 .20 .7 .92 Oct Jan Jan Oct Oct 11.6 15.7 1990 8.62 1992 - 1992 1991 1992 7 1990 13 1991 9 1991 7 1990 7 1990 47 RIO GOAJATACA BASIN 50010500 RIO GOAJATACA AT LARES, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°18'01", long 66°52'24", at bridge on Highway 111 (km 32.9), 0.1 mi (0.2 km) Quebrada An6n, and 0.4 mi (0.6 km) northeast of Lares plaza. DRAINAGE AREA.--3.16 mi> (8.18 km>). PERIOD OF RECORD.--Water years 1958-71, 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 upstream from DATE OCT 1991 22. .. DEC 17... FBB 1992 20. .. APR 09. .. JUL 02. .. AUG 27. .. TIME 0855 1320 1510 0805 1010 0935 DIS- CHARGE, INST. CUBIC FEET PER SECOND 7.6 0.98 1.1 1.4 1.9 5.9 SPE- CIFIC CON- DUCT- ANCE (US/CM) 216 241 247 268 235 252 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.4 7.9 7.9 6.9 7.8 6.9 TEMPER- ATURE WATER (DBG C) 21.0 21.5 23.5 21.5 24.0 25.5 TUR- BID- ITY (NTU) 9.0 3.3 1.4 1.4 0.50 4.7 OXYGEN, DIS- SOLVED (MG/L) 7.6 7.5 8.7 8.1 8.0 5.4 OXYGEN, OXYGEN DIS- DEMAND, SOLVED CHEM- (PBR- ICAL CENT (HIGH SATUR- LEVEL) ATI ON) (MG/L) 87 <10 86 <10 103 <10 99 <10 94 <10 68 <10 COLI- FORM, FECAL, 0.7 UM-MF (COLS./ 100 ML) K11000 K90 490 K13000 700 630 STREP- TOCOCCI FECAL, KF AGAR (COLS. PER 100 ML) 9300 5300 770 4300 470 4100 DATE OCT 1991 22. .. DEC 17. .. FBB 1992 20. .. APR 09. .. JUL 02... AUG 27. .. HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MG/L TOT FLD SOLVED AS MG/L AS (MG/L CAC03) CAC03 MAGNE- SIUM, DIS- SODIUM, DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS NA) SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY SIUM, WAT WH DIS- SOLVED AS K) CHLO- SULPATB RIDE, TOT PET SULFIDB DIS- DIS- FIBLD TOTAL SOLVED SOLVED (MG/L MG/L AS (MG/L (MG/L CAC03 (MG/L AS S) AS S04) AS CL) 78 3 23 5.1 9.5 0.5 2.5 77 <0.5 6.4 11 84 100 100 2 32 6.0 12 0.5 3.0 99 <0.5 14 17 no 110 0 33 5.8 11 0.5 3.0 110 — 13 13 SOLIDS, RESIDUE DATE OCT 1991 22.. . DEC 17. .. FEB 1992 20.. . APR 09.. . JUL 02.. . AUG 27. .. FLUO- RIDB, DIS- SOLVED (MG/L AS P) 0.20 -- -- 0.20 -- <0.10 SILICA, DIS- SOLVED (MG/L AS SI02) 28 -- -- 27 -- 24 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 132 -- -- 171 -- 168 SOLIDS, DIS- SOLVED (TONS PER DAY) 2.69 -- — 0.66 -- 2.67 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) <1 1 6 13 <1 1 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 2.29 1.67 -- 0.980 1.79 1.69 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.010 0.030 <0.010 0.020 0.010 0.010 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 2.30 1.70 0.870 1.00 1.80 1,70 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.050 0.020 0.020 0.040 0.020 0.040 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.15 — — 0.16 0.28 -- non-ideal count 48 RIO QOAJATACA BASIN 50010500 RIO GDAJATACA AT LARES, PR--Continued HATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 22... DEC 17. .. FEB 1992 20.. . APR 09.. . JUL 02.. . AUG 27.. . DATE OCT 1991 22... DEC 17... FEB 1992 20.. . APR 09.. . JUL 02. .. AUG 27.. . NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.20 <0.20 <0.20 0.20 0.30 <0.20 IRON, TOTAL RECOV- ERABLE (UG/L AS FE) NITRO- GEN, TOTAL (MG/L AS N) 2.5 — — 1.2 2.1 -- LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS NO3) 11 -- -- 5.3 9.3 -- MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.070 0.130 0.120 0.040 0.060 0.080 MERCURY TOTAL RECOV- ERABLE (UG/L AS HO) ARSENIC TOTAL (UG/L AS AS) <1 -- -- 2 -- -- SELE- NIUM, TOTAL (UG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 -- — <100 -- — SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) 30 -- -- 30 -- -- ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (OG/L AS CD) <1 — — <1 -- -- CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) <1 -- -- <1 -- -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) <10 - -- <10 — -- METHY- LENE BLUE ACTIVE SUB- STANCE (MG/L) 370 170 10 30 30 <0.10 <0.10 <0.010 <0.010 0.03 0.03 49 RIO GDAJATACA BASIN 50011000 CANAL PRINCIPAL DE DIVBRSIONBS AT LAQO DE GDAJATACA, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°24'02", long 66°55'27", off Highway 476 at Lago Quajataca outlet, 3.0 ml (4.8 km) southwest of Segunda Onidad Baldorioty de Castro, and 5.3 ml (8.5 km) south of Quebradillas Plaza. DRAINAGE AREA.--Indeterminate. PERIOD OP RECORD.--Water years 1958-64, 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DIS- PH OCT 1991 22. .. DEC 17. .. PEB 1992 20. .. APR 10. .. JUL 07. .. AUG 27. . . OCT 1991 22. .. DEC 17. .. PEB 1992 20. .. APR 10. . . JUL 07. .. AUG 27. .. TIME 1345 1545 1000 1045 1050 1230 HARD- NESS TOTAL (MG/L AS CAC03 ) CHARGE, INST. CUBIC PEBT PER SECOND B105 E100 E70 E50 E50 E75 HARD- NESS NONCARB WH WAT TOT PLD MG/L AS CACO3 SPE- CIFIC CON- DUCT- ANCE (US/CM) 312 300 318 282 310 318 CALCIUM DIS- SOLVED (MG/L AS CA) WATER WHOLE FIELD (STAND- ARD UNITS) 7.3 7.4 7.6 6.8 6.9 6.7 MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) TEMPER- ATURE WATER (DEG C) 25.5 25.0 24.5 25.5 25.0 27.5 SODIUM, DIS- SOLVED (MG/L AS NA) 150 130 54 46 150 10 53 3.7 7.4 3.6 5.9 3.4 5.9 TUR- BID- ITY (NTU) 3.9 1.2 1.2 1.2 1.5 0.2 SODIUM AD- SORP- TION RATIO 0.3 -- -- 0.2 -- 0.2 OXYGEN, DIS- SOLVED (MG/L) 2.3 2.9 2.7 5.5 1.7 2.6 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 2.6 — — 2.1 -- 2.3 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 12 36 32 67 28 39 ALKA- LINITY WAT WH TOT PET FIELD MG/L AS CAC03 140 130 130 110 150 160 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 10 11 <10 17 12 <10 SULPIDE TOTAL (MG/L AS S) <0.5 -- — <0.5 — — COLI- PORM, FECAL, 0.7 UM-MF (COLS./ 100 ML) 20 K5 K2 29 10 330 SULPATE DIS- SOLVED (MG/L AS S04) 13 -- -- 7.6 -- 8.0 STREP- TOCOCCI FECAL, KP AGAR (COLS. PER 100 ML) K13 Kl Kll 20 10 2500 CHLO- RIDE, DIS- SOLVED (MG/L AS CL) 12 — — 15 -- 9.5 SOLIDS, RESIDUE DATE OCT 1991 22. . . DEC 17. .. PEB 1992 20.. . APR 10. . . JUL 07. .. AUG 27.. . PLUO- RIDE, DIS- SOLVED (MG/L AS P) 0.20 -- -- 0.20 -- <0.10 SILICA, DIS- SOLVED (MG/L AS SI02) 7.5 -- -- 4.6 -- 5.6 SUM OP CONSTI- TUENTS, DIS- SOLVED (MG/L) 184 -- -- 151 -- 176 SOLIDS, DIS- SOLVED (TONS PER DAY) -- -- -- -- -- -- TOTAL AT 105 DEG. C, SUS- PENDED (MG/L) 2 1 <1 6 <1 2 NITRO- NITRO- NITRO- NITRO- NITRO- GEN, GEN, GEN, GEN, GEN, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC TOTAL TOTAL TOTAL TOTAL TOTAL (MG/L (MG/L (MG/L (MG/L (MG/L AS N) AS N) AS N) AS N) AS N) 0.068 0. 0. 0. 0. 0. 0. 010 010 010 010 030 010 <0 0 <0 <0 <0 <0 .050 .078 .050 .050 .050 .050 0. 0. 0. 180 030 020 0.160 0. 0. 130 320 0. 0. 0. 0. 0. 0. 32 27 38 24 17 28 B = estimate K = non-ideal count 50 RIO GOAJATACA BASIN 50011000 CANAL PRINCIPAL DB DIVBRSIONBS AT LAGO DE QUAJATACA, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 22.. . DEC 17.. . FBB 1992 20.. . APR 10... JUL 07... AUG 27.. . DATE OCT 1991 22.. . DEC 17... FBB 1992 20.. . APR 10. . . OUL 07.. . AUG 27.. . NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.50 0.30 0.40 0.40 0.30 0.60 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) — 0.38 — — — -- LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N03) — 1.7 -- -- -- -- MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.020 <0.010 0.070 •cO.010 <0.010 0.020 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) ARSENIC TOTAL (UG/L AS AS) 3 -- -- 1 — -- SELE- NIUM, TOTAL (UG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 — — <100 — -- SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) 30 -- -- 30 -- -- ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 — -- <1 — -- CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) <1 -- -- <1 -- -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) <10 — — <10 — -- MBTHY- LENE BLUB ACTIVE SUB- STANCE (MG/L) 200 200 160 160 <0.10 <0.10 20 •cO.010 •cO.010 0.03 0.11 51 RIO GUAJATACA BASIN 50011400 RIO GUAJATACA ABOVE MOUTH NEAR QUBBRADILLAS, PR HATER-QUALITY RECORDS LOCATION.—Lat 18°28'31", long 66°57'46", Hydrologic Unit 21010002, on left bank at ford 1.7 mi (2.7 km) upstream from bridge on highway 2, 1.6 mi (2.6 km) weat of Quebradillaa plaza, 2.1 mi (3.4 km) upstream from Atlantic Ocean, and 6.6 mi (10.6 km) downstream from Lago Quajataca. DRAINAGE AREA.--Indeterminate PERIOD OF RECORD.—Hater years 1969 to current year. HATER-QOALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 OCT 22 JAN 10 PBB 20 APR 10 JUL 20 SEP 02 DATE 1991 ... 1992 . . . . . . . . . TIME 1630 1230 0800 0905 1030 1200 DIS- CHARGE, INST. CUBIC FEET PER SECOND 226 6.6 9.3 14 33 250 SPE- CIFIC CON- DUCT- ANCE (US/CM) 318 556 612 399 395 307 PH HATER WHOLE FIELD (STAND- ARD UNITS) 8.2 7.6 7.5 6.9 7.4 7.9 TEMPER- ATURE HATER (DBG C) 26.0 24.5 24.0 24.5 25.0 27.0 TUR- BID- ITY (NTU) 15 0.70 0.50 1.4 2.1 3.5 OXYGEN, DIS- SOLVED (MG/L) 4.1 5.9 4.5 5.4 6.3 6.2 OXYGEN, OXYGEN DIS- DEMAND, SOLVED CHBM- (PBR- ICAL CENT (HIGH SATUR- LEVEL) ATION) (MG/L) 47 20 68 <10 49 <10 63 <10 72 13 70 <10 COLI- FORM, FECAL, 0.7 UM-MP (COLS./ 100 ML) K840 40 31 2100 410 K270 STREP- TOCOCCI FECAL, KF AGAR (COLS. PER 100 ML) 880 110 54 3200 410 670 DATE OCT 1991 22. .. JAN 1992 10... PBB 20... APR 10... JUL 20. .. SEP 02... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH HAT DIS- (MG/L TOT FLD SOLVED AS MG/L AS (MG/L CAC03) CAC03 160 8 57 180 19 64 150 8 56 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS NA) 3.5 6.1 5.9 12 3.5 5.4 SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY SIUM, HAT WH CHLO- SULFATB RIDE, DIS- TOT FBT SULFIDB DIS- DIS- SOLVED FIELD TOTAL SOLVED SOLVED (MG/L MG/L AS (MG/L AS K) 0.2 1.9 0.4 1.7 0.2 1.7 CACO3 150 210 230 160 180 150 (MG/L (MG/L AS S) AS SO4) AS CL) <0.5 13 11 <0.5 8.5 26 9.2 11 SOLIDS, RESIDUE DATE OCT 1991 22.. . JAN 1992 10... FBB 20.. . APR 10... JUL 20... SEP 02.. . PLUO- RIDB, DIS- SOLVED (MG/L AS P) 0.20 -- -- 0.20 -- 0.10 SILICA, DIS- SOLVED (MG/L AS SI02) 7.4 -- -- 5.9 — 6.0 SUM OP CONSTI- TUENTS, DIS- SOLVED (MG/L) 190 -- -- 220 -- 181 SOLIDS, DIS- SOLVED (TONS PER DAY) 116 -- -- 8.38 -- 122 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) <1 7 4 7 28 <1 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.190 1.98 2.68 1.08 -- 0.280 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.020 0.020 0.020 0.020 <0.010 0.040 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 0.210 2.00 2.70 1.10 <0.050 0.320 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.070 0.030 0.020 0.040 0.020 0.020 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.83 — — — 0.38 0.18 K = non-ideal count 52 RIO GUAJATACA BASIN 50011400 RIO GUAJATACA ABOVE MOUTH NEAR QUEBRADILLAS, PR- -Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 22.. . JAN 1992 10. .. FBB 20.. . APR 10.. . JUL 20... SEP 02... DATE OCT 1991 22.. . JAN 1992 10. .. FBB 20. . . APR 10. .. JUL 20... SEP 02. . . NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.90 <0.20 <0.20 <0.20 0.40 0.20 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) 450 -- -- 140 -- -- NITRO- NITRO- GEN, GEN, TOTAL TOTAL (MG/L (MG/L AS N) AS N03) 1.1 4.9 __ __ __ __ 0.52 2.3 MANGA- LBAD, NBSB, TOTAL TOTAL RECOV- RECOV- ERABLE BRABLB (UG/L (UG/L AS PB) AS MN) 18 60 __ __ <1 40 __ __ PHOS- PHORUS ARSENIC TOTAL TOTAL (MG/L (UG/L AS P) AS AS) 0.040 3 •eO.010 0.020 •cO.010 <1 0.020 0.020 MERCURY TOTAL SBLE- RECOV- NIUM, BRABLB TOTAL (UG/L (UG/L AS HG) AS SB) •eO.10 <1 __ __ <0.10 <1 __ __ BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 -- -- <100 -- -- SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) <1 -- -- <1 -- -- CHRO- BORON, CADMIUM MIUM, TOTAL TOTAL TOTAL RBCOV- RECOV- RECOV- ERABLE BRABLB BRABLB (UG/L (UG/L (UG/L AS B) AS CD) AS CR) 30 <1 1 __ __ 30 <1 <1 __ — — — — — — ZINC, TOTAL RBCOV- CYANIDE BRABLB TOTAL PHENOLS (UG/L (MG/L TOTAL AS ZN) AS CN) (UG/L) 30 <0.010 <1 __ __ <10 <0.010 3 __ __ COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) 10 -- -- <10 -- -- METHY- LENE BLUB ACTIVE SUB- STANCE (MG/L) 0.03 — — 0.03 -- -- ATLANTIC OCEAN s .0157 .0148 AHEC'BO ' f J ••" / »v /' // \^:- \ ,—V I IJT1 >»!<>!•>___ '••«. ^S ««<liiiv»ntary iccfc* UTUAOO EXPLANATION CMS SURFACE-WATER STATION AND NUMBER , Vap I 1 T^ 0123^56 KILOMETERS 01 234 MILES Figure 14-Rio Camuy basin. 54 RIO CAMUY BASIN 50014600 RIO CAMUY AT TRBS PUEBLOS SINKHOLE, PR LOCATION.—Lat 18°20'42", long 66°49'29", Hydrologic Unit 21010002, at Parque de lac Cavema• del Rio Camuy, 1.8 ml (2.9 km) southeast from Escuela Segunda Dnidad de Santiago Palmer, 4.7 mi (7.6 km) tract from Observatorio de Arecibo and 4.8 mi (7.7 km) northeast from Plaza de Lares. DRAINAGE AREA.—Indeterminate. WATER-DISCHARGE RECORDS PERIOD OF RECORD.—June 1990 to current year. GAGE.—Water-stage recorder and crest-stage gage. Datum of gage is 612.21 ft (186.602 m), above mean sea level. REMARKS.--Records fair except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN APR MAY JUN JUL AUG 1 56 160 2 55 95 3 49 77 4 47 71 5 46 66 6 45 62 7 44 60 8 141 59 9 115 57 10 77 55 11 59 54 12 54 e53 13 70 e52 14 70 eSO 15 54 50 16 51 50 17 47 49 18 86 48 19 116 47 20 166 46 21 161 45 22 117 44 23 89 43 24 79 43 25 95 42 26 89 41 27 71 41 28 79 40 29 76 39 30 74 39 31 274 —— TOTAL 2652 1678 MEAN 85.5 55.9 MAX 274 160 MIN 44 39 AC-FT 5260 3330 e Estimated STATISTICS OF MONTHLY MEAN MEAN 98.8 53.3 MAX 112 55 . 9 (WY) 1991 1992 MIN 85.5 50.7 (WY) 1992 1991 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 38 37 37 36 36 35 35 34 34 33 33 32 32 e32 e31 30 30 30 30 33 40 32 31 30 29 29 29 29 28 28 28 1001 32.3 40 28 1990 DATA 31.1 32.3 1992 29.8 1991 FOR 28 27 27 27 27 67 35 30 29 28 33 39 30 28 26 26 25 24 24 24 23 23 23 23 23 23 22 22 21 21 21 849 27.4 67 21 1680 FOR WATER 24.5 27.4 1992 21.6 1991 21 20 21 21 20 20 20 19 18 18 18 18 18 17 17 17 17 16 16 16 16 16 16 16 16 15 15 15 14 --- 507 17.5 21 14 1010 YEARS 1990 22.2 27.0 1991 17.5 1992 14 15 15 15 15 15 34 32 21 20 28 19 18 17 17 17 19 20 18 18 18 17 17 17 64 62 30 72 233 101 49 1067 34.4 233 14 2120 - 1992 26.5 34.4 1992 18.5 1991 1991 CALENDAR YEAR 17258 47.3 274 15 16 88 36 20 Oct 31 Mar 16 Mar 13 41 36 33 31 30 30 33 33 49 50 47 38 38 34 32 59 71 56 85 62 46 41 39 37 36 35 34 33 32 32 --- 1253 41.8 85 30 2490 33 38 34 32 31 31 30 30 29 31 82 143 79 58 47 49 49 58 147 104 128 109 176 166 129 114 88 86 123 114 134 2502 80.7 176 29 4960 114 88 76 69 65 115 147 215 130 90 79 70 64 59 57 55 52 51 49 47 46 45 44 43 42 41 40 40 39 38 —— 2110 70.3 215 38 4190 37 37 37 39 38 36 35 36 37 35 41 38 35 33 33 32 31 31 32 49 44 41 34 36 42 34 52 61 38 35 70 1209 39.0 70 31 2400 58 46 38 36 38 111 96 65 53 50 46 44 74 63 46 42 40 41 39 46 46 44 45 69 125 103 56 46 44 41 39 1730 55.8 125 36 3430 73 57 44 42 40 41 58 64 53 51 49 44 41 40 40 41 42 40 39 70 47 42 57 59 49 45 42 39 38 64 —— 1451 48.4 73 38 2880 , BY WATER YEAR (WY) 43.3 44.9 1991 41.8 1992 FOR 1992 18009 49. 274 14 15 1030 12. 14 88 40 18 77.5 80.7 1992 74.2 1991 WATER YEAR 2 Oct 31 Feb 29 Feb 26 Oct 31 42 Oct 31 Feb 28 47.1 70.3 1992 32.1 1991 34.2 43.1 1991 20.7 1990 WATER 49 49 48 274 14 15 1030 12 14 89 37 19 50.2 66.0 1991 28.8 1990 YEARS 1990 - .1 .2 .9 Oct 31 Feb 29 Feb 26 Oct 31 .42 Oct 31 Feb 28 61.3 70.9 1990 48.4 1992 1992 1992 1991 1991 1992 1992 1991 1991 1992 RIO CAMUY BASIN 50014800 RIO CAMUY NEAR BAYANBY, PR 55 LOCATION.--Lat 18«23'48", long 66°49'04", Hydrologlc Unit 21010002, on left bank at Highway 488, 1.4 mi (2.2 km) southeast of school at Santiago, 0.9 mi (1.4 km) northwest from Bscuela Manual A. Rivera at Bayaney and 9.1 mi (14.6 km) upstream from Atlantic Ocean. DRAINAGE AREA.--Indeterminate. WATER-DISCHARGE RECORDS PERIOD OF RECORD.--May 1984 to current year. GAGE.—Water-stage recorder. Elevation of gage is 341 ft (104 m), from topographic map. REMARKS.--Records fair except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. DAY OCT DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES NOV DEC JAN FBB MAR APR MAY JUN JUL AOG SEP 1 92 458 2 96 208 3 83 160 4 80 146 5 77 134 6 73 126 7 71 149 8 314 133 9 303 113 10 195 107 11 122 104 12 98 99 13 124 96 14 129 93 15 92 90 16 84 89 17 80 87 18 157 84 19 235 81 20 395 78 21 356 77 22 234 75 23 163 75 24 137 77 25 170 77 26 173 77 27 128 77 28 152 76 29 150 75 30 141 73 31 620 --- TOTAL 5324 3394 MEAN 172 113 MAX 620 458 MIN 71 73 e Estimated STATISTICS OF MONTHLY MEAN MEAN 220 127 MAX 427 244 (WY) 1986 1986 MIN 81.6 74.9 (WY) 1988 1989 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN -DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 71 70 68 68 65 64 63 61 61 60 58 56 55 55 55 53 53 52 51 55 77 54 46 45 43 42 41 40 40 40 39 1701 54.9 77 39 DATA 67.4 97.4 1988 49.7 1989 FOR 39 39 39 39 39 124 71 48 45 44 46 73 54 45 41 39 38 37 36 36 36 35 35 35 34 35 35 34 34 33 34 1352 43.6 124 33 FOR WATER 48.5 80.9 1988 33.1 1991 33 33 36 36 35 34 33 30 29 28 28 28 28 28 28 29 28 28 28 29 29 28 26 26 26 26 26 26 26 ___ ___ 848 29.2 36 26 YEARS 1984 46.7 78.3 1987 29.2 1992 26 25 25 25 25 25 52 86 35 30 48 30 27 27 26 26 31 33 28 27 26 26 26 25 97 134 49 140 541 239 87 2047 66.0 541 25 - 1992 48.2 66.0 1992 35.7 1991 1991 CALENDAR YEAR 35824 98. 620 26 27 197 74 31 1 Oct 31 Feb 2 Jan 28 65 47 40 35 35 33 40 38 71 85 104 75 54 45 40 77 133 102 215 110 75 59 49 45 43 40 38 37 35 34 --- 1899 63.3 215 33 36 52 42 36 34 35 32 31 30 31 100 304 163 99 74 68 79 78 319 224 329 258 549 465 311 336 210 179 257 253 305 5319 172 549 30 261 193 155 133 132 217 306 eS20 e295 e!88 e!66 e!31 el20 ellS e!07 e96 e93 e91 e84 e83 e80 e78 e76 e77 e73 e72 e71 e73 e71 e68 4225 141 520 68 e66 e67 e86 e89 e79 e70 e66 e66 73 66 65 85 66 59 56 54 53 139 101 92 123 109 70 60 77 64 75 116 63 55 117 2427 78.3 139 53 112 80 68 63 61 202 187 110 82 77 71 64 95 173 90 74 72 71 69 71 73 81 127 158 254 229 121 91 82 74 71 3253 105 254 61 126 111 80 74 71 70 98 158 119 93 93 81 75 73 72 77 77 75 79 191 104 86 153 145 109 102 95 90 81 118 2976 99.2 191 70 , BY WATER YEAR (WY) 106 202 1986 61.4 1990 FOR 1992 34765 95 620 25 25 2500 12 25 189 73 29 196 624 1986 43.2 1989 WATER YEAR .0 Oct 31 Mar 2 Feb 29 Oct 31 .61 Oct 31 Mar 2 109 141 1992 79.9 1989 82.5 109 1989 58.4 1984 WATER 108 179 89 3820 25 25 6450 17 25 210 70 35 96.4 135 1989 54.2 1987 YEARS 1984 - .3 Oct 7 Apr 27 Feb 29 Oct 7 .66 Oct 7 Apr 26 151 273 1984 99.2 1992 1992 1986 1989 1985 1989 1992 1985 1985 1989 56 RIO CAMOY BASIN 50015700 RIO CAMUY NEAR HATILLO, PR LOCATION.--Lat 18°27'44", long 66 0 49'56", Hydrologic Unit 21010002, 1.8 mi (2.9 km) southwest of Hatillo plaza, and 1.8 mi (2.9 km) southeast of Camuy plaza, 1.2 mi (1.9 km) south of Planta de Purificaci6n, and 3.3 mi (5.5 km) upstream from Atlantic Ocean. DRAINAGE AREA.--Indeterminate. WATER-DISCHARGE RECORDS PERIOD OF RECORD.--June 1984 to current year. GAGE.--Water-stage recorder. Elevation of gage is 13 ft (4 m), from topographic map. REMARKS.--Records fair except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES OCT NOV DEC JAN FEB MAR JUN JUL AUG 1 103 1220 2 119 284 3 96 176 4 89 151 5 86 135 6 81 124 7 78 147 8 302 168 9 655 113 10 391 105 11 207 102 12 155 97 13 148 92 14 188 88 15 113 85 16 99 85 17 92 83 18 161 81 19 270 78 20 579 75 21 615 74 22 416 72 23 305 71 24 196 69 25 241 68 26 267 66 27 183 64 28 183 64 29 262 62 30 178 61 31 634 --- TOTAL 7492 4160 MEAN 242 139 MAX 655 1220 MIN 78 61 e Estimated STATISTICS OF MONTHLY MEAN MEAN 381 194 MAX 735 439 (WY) 1986 1986 MIN 116 115 (WY) 1988 1989 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 59 58 57 57 56 55 54 54 53 52 51 50 49 51 50 49 48 48 47 50 80 56 49 47 46 45 45 45 45 44 44 1594 51.4 80 44 DATA 83.1 151 1988 51.4 1992 FOR 44 44 42 42 43 147 80 52 47 46 45 75 59 47 43 42 41 40 40 40 39 39 39 39 38 39 38 38 38 38 38 1482 47.8 147 38 FOR WATER 62.9 131 1988 46.2 1989 37 37 38 41 38 37 37 36 35 34 34 34 34 34 34 33 33 33 33 32 32 32 32 32 32 32 32 31 31 ___ --- 990 34.1 41 31 YEARS 1984 68.1 134 1987 34.1 1992 31 31 31 31 31 31 35 108 41 36 49 36 33 33 33 32 33 40 36 34 34 33 32 32 50 236 40 60 688 660 102 2732 88.1 688 31 - 1992 69.0 88.1 1992 49.2 1988 1991 CALENDAR YEAR 49447 135 1600 37 38 288 75 42 Apr 26 Feb 2 Mar 11 77 57 48 43 40 38 45 44 77 89 127 111 62 49 43 42 171 143 162 153 78 64 53 49 46 43 42 40 39 39 --- 2114 70.5 171 38 41 60 48 41 38 38 37 35 34 34 59 454 310 112 77 73 95 71 354 508 464 568 1250 1090 636 838 565 302 425 484 508 9649 311 1250 34 569 390 306 266 371 274 578 795 645 280 251 173 144 130 ellO elOO e99 e97 e91 e89 e86 e83 e82 e81 e78 e76 e76 e78 e76 e72 --- 6546 218 795 72 e70 e71 e91 e94 e86 e76 e70 e70 e78 e71 e69 e91 e70 e64 e60 e58 e56 e!50 ellO e98 e!30 e!20 e74 e62 e82 e66 e58 176 74 63 107 2615 84.4 176 56 180 87 68 63 64 133 390 126 79 73 66 62 58 290 128 79 73 71 69 75 76 82 138 365 340 531 181 127 100 88 83 4345 140 531 58 124 181 88 82 76 75 91 223 177 77 105 76 67 65 64 76 71 67 64 326 133 84 164 223 126 112 159 157 80 101 --- 3514 117 326 64 , BY WATER YEAR (WY) 190 411 1986 70.5 1992 FOR 1992 47233 129 1250 31 31 4430 18, 303 72 34 394 1586 1986 59.5 1989 WATER YEAR May 23 Feb 28 Feb 28 Nov 1 , 16 Nov 1 150 218 1992 105 1991 111 161 1990 65.6 1984 WATER 170 335 129 8150 25 30 10700 24, 321 82 42 124 180 1989 71.6 1990 YEARS 1984 - Oct 7 May 30 May 19 Oct 7 . 7 5 Oct 7 206 376 1989 117 1992 1992 1986 1992 1985 1990 1990 1985 1985 RIO CAMUY BASIN 50015700 RIO CAMUY NEAR HATILLO, PR--Continued WATER QUALITY RECORDS PERIOD OP RECORD.--WATER YEARS AUGUST 1984 TO CURRENT YEAR DATE TIME FEB. 21 0848 AUG. 19 1404 STREAMFLOW, INSTANTANEOUS (CFS) 32 69 SPECIFIC CON- DUCTANCE (UMHOS) 320 220 TEMPERA- TURE (DBG C) 21.5 26.0 DATE TIME SEP. 19 1250 STREAMFLOW, INSTANTANEOUS (CFS) 114 SPECIFIC CON- DUCTANCE (UMHOS) 180 57 TEMPERA- TURE (DBG C) 28.0 THIS PAGE WAS LEFT BLANK INTENTIONALLY 59 V /' V- i , ^ ,7/<<n » 0J / .>VX *<> . .. v-^ ; x"^^w ~~ ^ / f-T -bonndfs; y -/ y. ft-. Y_.> l»ior)d \ ;?>-/". """- \ x--*y "''•" —— Moo \«*.»au€j > *V*r t- C»4U»1, «utr>iii J "•-^ B0*t > "• EXPLANATION ^0284 SURFACE-WATER STATION AND NUMBER y 0205 QUALITY-OF-WATER STATION AND NUMBER Y7 020050 QUALITY-OF-WATER PARTIAL RECORD v STATION AND NUMBER • 204 WELL AND WELL NUMBER • 026140 LAKE-ELEVATION STATION 0123456 KILOMETERS -—----- ~'~-H—• T 1 234 ?v,il.Eb Figure 15r-Rio Grande de Arecibo basin. 60 RIO GRANDB DB ARBCIBO BASIN 50020500 RIO QRANDB DB ARBCIBO NEAR ADJUNTAS, PR WATER-QUALITY RECORDS LOCATION.—Lat 18°10'54", long 66°44'12", at Highway 135 bridge, 1.0 mi (1.6 km) upatream from Lago Adjuntaa, and 1.5 mi (2.4 km) northwest of Adjunta* plaza. DRAINAGE AREA.--12.7 mi> (32.9 km 1 ) thia doe a not include 6.0 mi> (15.6 km 1 ) above Lago Garzaa. PERIOD OF RECORD.--Water year* 1969-74, 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE NOV 1991 06. .. JAN 1992 07. .. FEB 27. .. APR 03... JUN 11... AUG 21... TIME 1230 1545 1030 1000 1025 0950 DIS- CHARGE, INST. CUBIC FEET PER SECOND 22 48 11 41 27 18 SPE- CIFIC CON- DUCT- ANCE (US/CM) 417 333 335 265 280 515 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.7 7.4 7.7 7.4 7.5 7.4 TEMPER- ATURE WATER (DBG C) 24.0 23.0 21.0 22.0 24.0 23.5 TUR- BID- ITY (NTU) 13 12 0.50 4.3 1.2 1.1 OXYGEN, DIS- SOLVED (MG/L) 7.5 7.4 8.5 9.0 9.6 6.2 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 81 83 100 105 109 70 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 48 <10 16 12 18 16 COLI- FORM, FECAL, 0.7 UM-MF (COLS./ 100 ML) 4100 K1300 250 K1600 70 4900 STREP- TOCOCCI FECAL, KF AGAR (COLS. PER 100 ML) 9200 3500 5100 4700 260 24000 DATE NOV 1991 06... JAN 1992 07. .. FEB 27. .. APR 03. .. JUN 11. .. AUG 21... HARD- NESS TOTAL (MG/L AS CACO3) 110 HARD- NESS NONCARB CALCIUM WH WAT TOT FLD CACO3 DIS- SOLVED MG/L AS (MG/L 120 29 26 33 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS NA) 9.0 53 8.0 15 9.8 46 ALKA- SODIUM POTAS- LINITY AD- SIUM, WAT WH SORP- DIS- TOT FBT SULFIDB TION SOLVED FIELD TOTAL RATIO (MG/L MG/L AS (MG/L AS K) 3.6 0.7 3.5 2.9 CACO3 94 77 110 100 100 120 CHLO- SULFATB RIDE, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS S) AS SO4) AS CL) cO.5 9.3 86 cO.5 14 24 11 73 DATE NOV 1991 06... JAN 1992 07... FEB 27... APR 03... JUN 11... AUG 21... FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.10 -- -- 0.10 -- 0.20 SILICA, DIS- SOLVED (MG/L AS SI 02) 29 -- -- 23 — 27 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 275 -- -- 174 -- 273 SOLIDS, DIS- SOLVED (TONS PER DAY) 16.2 -- -- 19.0 — 13.3 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 10 7 1 1 3 8 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 1.12 1.37 1.14 1.08 0.740 0.650 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.080 0.030 0.060 0.020 0.050 0.080 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 1.20 1.40 1.20 1.10 0.790 0.730 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.170 0.160 0.040 0.110 0.020 0.070 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 1.0 0.34 0.16 0.09 -- 0.33 non-ideal count RIO GRANDB DB ARBCIBO BASIN 50020500 RIO GRANDB DB ARBCIBO NR ADJUNTAS, PR--Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1991 TO SBPTBMBBR 1992 61 DATE NOV 1991 06... JAN 1992 07.. . FBB 27... APR 03... JUN 11.. . ADG 21... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 1.2 0.50 0.20 0.20 <0.20 0.40 NITRO- GEN, TOTAL (MG/L AS N) 2.4 1.9 1.4 1.3 — 1.1 NITRO- GEN, TOTAL (MG/L AS N03) 11 8.4 6.2 5.8 -- 5.0 PHOS- PHORUS ARSENIC TOTAL TOTAL (MG/L (DG/L AS P) AS AS) 0.220 1 0.110 0.170 0.080 <1 0.080 0.190 BARIUM, TOTAL RECOV- ERABLE (DG/L AS BA) <100 — -- <100 -- — CHRO- BORON, CADMIUM MIUM, COPPER, TOTAL TOTAL TOTAL TOTAL RBCOV- RECOV- RBCOV- RECOV- ERABLE BRABLE BRABLE BRABLB (DG/L (DG/L (DG/L (UG/L AS B) AS CD) AS CR) AS CD) 20 <1 <1 50 __ __ <10 <1 <1 <10 __ — DATE NOV 1991 06... JAN 1992 07.. . FBB 27.. . APR 03... JUN 11.. . ADG 21... IRON, TOTAL RECOV- ERABLE (DG/L AS FB) LEAD, TOTAL RECOV- ERABLE (DG/L AS PB) MANGA- NESE, TOTAL RECOV- ERABLE (DG/L AS MN) MERCURY TOTAL RECOV- ERABLE (DG/L AS HG) SELE- NIUM, TOTAL (DG/L AS SB) SILVER, TOTAL RECOV- ERABLE (DG/L AS AG) ZINC, TOTAL RECOV- ERABLE (DG/L AS ZN) CYANIDE TOTAL (MG/L AS CN) PHENOLS TOTAL (DG/L) METHY- LBNE BLUB ACTIVE SUB- STANCE (MG/L) 1400 420 90 40 <0.10 0.20 20 <0.010 <0.010 0.09 0.05 62 RIO ORANDE DB ARBCIBO BASIN 50025000 RIO GRANGE DB ARBCIBO NEAR DTUADO, PR WATER-QUALITY RBCORDS LOCATION.--Lat 18<>18'11', long 66°41'59", at bridge near Highway 10 at km 56.4, 0.5 mi (0.8 km) down*tream from Rio de Caguana, and 2.5 mi (4.0 km) north of Utuado plaza. DRAINAGE AREA.—66.0 mi 1 (170.9 km1 ) this excludes 6.0 mi 1 (15.5 km 1 ) upstream from Lago Garzas to Rio Guayanes in the Rio Tallaboa basin. PERIOD OF RECORD.—Water years 1959-74, 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 30. .. DEC 30... FBB 1992 27... APR 15. .. JDN 24. .. AUG 20. .. TIME 1140 1000 1140 1055 0940 1035 DIS- CHARGE, INST. CUBIC FEET PER SECOND 158 39 35 55 77 60 SPE- CIFIC CON- DUCT- ANCE (US /CM) 141 308 310 291 280 299 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.7 7.9 8.0 7.7 8.4 7.5 TEMPER- ATURE WATER (DBG C) 24.5 20.0 22.5 26.5 25.0 26.0 TUR- BID- ITY (NTU) 250 10 2.1 5.0 2.4 1.5 OXYGEN, DIS- SOLVED (MQ/L) 7.5 9.3 8.5 8.0 10.0 7.0 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 84 108 96 100 112 81 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 40 <10 <10 12 <10 17 COLI- FORM, FECAL, 0.7 UM-MF (COLS./ 100 ML) K69000 K1000 72000 K800 K110 410 STREP- TOCOCCI FECAL, KF AGAR (COLS. PER 100 ML) 30000 310 3900 300 380 230 DATE OCT 1991 30... DEC 30... FBB 1992 27... APR 15. .. •TUN 24. .. AUG 20. .. HARD- NESS TOTAL (MG/L AS HARD- NESS NONCARB CALCIUM WH WAT DIS- TOT FLD SOLVED MG/L AS CACO3) CAC03 66 (MG/L 18 110 21 31 110 13 30 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MS) AS NA) 5.2 9.7 8.5 16 8.4 16 SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY SIUM, WAT WH DIS- TOT FBT SULFIDB SOLVED FIELD TOTAL (MG/L MG/L AS (MG/L AS K) 0.5 3.0 0.7 2.4 0.7 2.3 CACO3 55 100 98 92 100 98 CHLO- SULFATB RIDE, DIS- DIS- SOLVED SOLVED (MG/L <0.5 17 <0.5 21 20 (MG/L AS S) AS SO4) AS CL) 12 18 20 OCT 30 DEC 30 FBB 27 APR 15 JUN 24 AUG 20 K = FLUO- RIDB, DIS- SOLVED DATE (MG/L AS F) 1991 <0.10 . . . -- 1992 <0.10 0.20 non- ideal count SILICA, DIS- SOLVED (MG/L AS SIO2) 18 -- — 23 — 28 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 116 -- -- 175 -- 184 RESIDUE SOLIDS, TOTAL NITRO- DIS- AT 105 GEN, SOLVED DBG. C, NITRATE (TONS SUS- TOTAL PER FENDED (MG/L DAY) (MG/L) AS N) 49.3 25.8 30 NITRO- NITRO- NITRO- NITRO- GEN, GEN, GEN, GEN, NITRITE NO2+NO3 AMMONIA ORGANIC TOTAL TOTAL TOTAL TOTAL (MG/L (MG/L (MG/L (MG/L AS N) AS N) AS N) AS N) 348 16 1 25 10 16 1.15 0.970 1.12 0.620 0.940 0.970 0.050 0.030 0.080 0.050 0.050 0.030 1.20 1.00 1.20 0.670 0.990 1.00 0.110 0.030 0.240 0.110 0.080 0.020 0.79 0.17 0.26 0.09 0.12 — RIO GRANDB DB ARBCIBO BASIN 50025000 RIO GRANDB DB ARBCIBO NEAR UTOADO, PR—Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 30... DEC 30... FEB 1992 27.. . APR 15... JUN 24... AUG 20.. . NITRO- GEN, AM- MONIA 4 ORGANIC TOTAL (MG/L AS N) 0.90 0.20 0.50 0.20 0.20 <0.?i NITRO- GEN, TOTAL (MG/L AS N) 2.1 1.2 1.7 0.87 1.2 -- NITRO- GEN, TOTAL (MG/L AS N03) 9.3 5.3 7.5 3.9 5.3 -- PHOS- PHORUS ARSENIC TOTAL TOTAL (MG/L (UG/L AS P) AS AS) 0.320 <1 0.180 0.230 0.100 <1 0.170 0.070 BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) 200 — — <100 — -- CHRO- BORON, CADMIUM MIUM, COPPER, TOTAL TOTAL TOTAL TOTAL RBCOV- RECOV- RBCOV- RECOV- ERABLE BRABLB ERABLB BRABLB (UG/L (UG/L (UG/L (UG/L AS B) AS CD) AS CR) AS CU) 50 <1 12 100 __ __ <10 <1 <1 20 __ __ DATE OCT 1991 30.. . DEC 30.. . FEB 1992 27.. . APR 15.. . JUN 24... AUG 20.. . IRON, TOTAL RECOV- ERABLE (UG/L AS FE) LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) SELE- NIUM, TOTAL (UG/L AS SB) SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CYANIDE TOTAL (MG/L AS CN) PHENOLS TOTAL (UG/L) MBTHY- LENE BLUE ACTIVE SUB- STANCE (MG/L) 14000 410 420 40 0.10 <0.10 50 10 <0.010 •eO.010 0.06 0.02 64 RIO GRANDB DB ARBCIBO BASIN 50025155 RIO SALIENTB AT COABBY NEAR JAYUYA, PR LOCATION.--Lat 18°12'48", long 66°33'49", Hydrologic Unit 21010002, 2.0 mi (3.2 km) southeast of Jayuya, 1.4 mi (2.2 km) northeast of Hacienda Gripifias. DRAINAGE AREA.--9.25 mi* (23.96 km1 ). HATER-DISCHARGE RECORDS PERIOD OF RECORD.—October 1989 to current year. GAGE.—Hater-stage recorder. Elevation of gage is 1,706 ft (520 m), from topographic map. REMARKS.--Records fair except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY NOV DEC JAN FBB MAR MAY JUN JUL AUG SEP 1 10 e!6 2 9.6 e!5 3 9.1 e!3 4 8.2 ell 5 7.9 elO 6 8.0 ell 7 14 e!3 8 17 e!5 9 16 e!3 10 18 e!2 11 16 ell 12 13 ell 13 10 elO 14 9.2 elO 15 8.8 10 16 8.6 10 17 8.1 9.4 18 11 9.2 19 12 8.8 20 8.8 8.7 21 9.9 8.5 22 16 8.5 23 15 8.2 24 12 11 25 8.5 10 26 8.3 7.9 27 7.5 8.2 28 7.4 9.8 29 17 8.7 30 19 7.9 31 e!7 --- TOTAL 360.9 315.8 MEAN 11.6 10.5 MAX 19 16 MIN 7.4 7.9 AC-FT 716 626 CFSM 1.26 1.14 IN. 1.45 1.27 e Estimated 7.5 7.3 7.4 8.7 8.9 8.7 7.7 6.7 6.6 6.6 6.5 6.3 6.3 6.3 e6.3 5.6 6.0 6.0 5.8 e!9 e21 elO e8.6 e8.2 e7.8 e7.4 e7.6 e7.6 e7.4 e7.2 e7.2 250.2 8.07 21 5.6 496 .87 1.01 STATISTICS OF MONTHLY MEAN DATA MEAN 36.8 23.6 MAX 70.5 40.0 (WY) 1991 1991 MIN 11.6 10.5 (WY) 1992 1992 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS LOW FLOH ANNUAL RUNOFF (AC- FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 12.0 17.9 1991 8.07 1992 FOR e7.0 e6.9 e6.9 e35 e450 e300 e!20 e60 e40 e34 e39 e39 e31 e27 e24 e25 e26 e21 e!9 e!7 e!6 e!6 e!5 el6 e!5 el5 e!4 el4 e!4 el4 e!4 1490.8 48.1 450 6.9 2960 5.20 6.00 e!3 e!3 e!2 e!2 e!5 e32 e32 630 621 e!7 elS e!4 e!6 e!6 e!4 e!3 e!2 ell ell elO elO elO elO e9.6 ell e9.4 elO ell elO 420.0 14.5 32 9.4 833 1.57 1.69 FOR HATER YEARS 1989 22.6 48.1 1992 7.19 1990 11.2 14.5 1992 6.00 1990 e9.4 e9.4 e9.2 e9.1 e9.0 e9.1 e9.6 elO e 12 e9.0 e8.4 e8.2 e8.0 e7.8 e8.4 elO elO e7.6 e7.1 e6.9 e8.6 e6.6 67.4 69.0 e7.8 e!2 e20 e52 e25 e!5 e20 361.6 11.7 52 6.6 717 1.26 1.45 - 1992 11.5 13.0 1991 9.90 1990 1991 CALENDAR YEAR 4700.2 12.9 75 5.2 6.0 9320 1.39 18.90 21 10 7.2 Mar 26 Aug 12 Dec 13 e26 e20 e!2 elO e!5 e26 e24 e56 e45 e!9 e!4 ell e!2 e25 e72 e55 e77 e!80 e!35 e66 e33 624 e!9 e!6 e!4 e!3 e!2 e!2 e!5 e21 1079 36.0 180 10 2140 3.89 4.34 , BY HATER 18.8 36.0 1992 7.01 1990 FOR 1992 8764 23 450 5 6 2900 5 17380 2 35 43 14 7 e35 e22 e!7 e!5 e!7 e!5 e!2 ell ell e!3 e26 e27 e49 e64 e45 e96 e76 e!23 e72 e48 e38 e!20 6170 e!20 e80 e!40 e80 e50 e40 638 e!40 1810 58.4 170 11 3590 6.31 7.28 YEAR (WY) 26.2 58.4 1992 5.35 1990 e!50 e74 e50 e42 e37 e34 e32 e31 e30 e38 e30 e26 e24 e23 e23 e22 e22 e21 e20 e20 e20 e!9 e!8 e!7 e!6 e!6 e!5 e!4 e!4 e!3 911 30.4 150 13 1810 3.28 3.66 17.2 30.4 1992 10.1 1991 HATER YEAR .1 .9 .6 .0 .5 .59 .25 .9 Jan 5 Dec 16 Dec 13 Jan 5 Dec 15 el? e!5 e!3 e!2 e!2 e!2 e!5 e!3 e!2 ell ell ell ell elO ell elO elO e9.8 e9.5 e8.9 e8.8 e!5 22 10 11 9.8 9.6 9.8 9.6 30 40 409.8 13.2 40 8.8 813 1.43 1.65 11.8 15.3 1991 6.85 1990 HATER 19 23 14 450 2 3 2900 14330 2 29 38 12 5 18 14 12 16 42 35 17 15 23 60 34 23 18 17 17 16 15 14 13 13 55 25 18 16 15 27 21 16 15 14 15 669 21.6 60 12 1330 2.33 2.69 17.8 21.6 1992 13.8 1990 YEARS 1989 - .8 .9 .3 Jan 5 .4 Jul 23 .4 May 22 Jan 5 .14 .06 .6 14 13 13 15 17 15 88 36 22 18 17 16 15 14 38 21 18 15 14 19 20 16 45 26 27 25 18 18 18 35 ___ 686 22.9 88 13 1360 2.47 2.76 27.5 45.2 1990 14.4 1991 1992 1992 1990 1992 1990 1990 1992 RIO GRANDE DE ARECZBO BASIN 50026050 RIO CACHILLAS ABOVE LAOO CAONILLAS NEAR JAYUYA, PR WATER-QDALITY RECORDS LOCATION.--Lat 18°13'26", long 66<>38'22", 300 ft (91 at) off Highway 531, 700 ft (213 at) upstream front Caonillas, 3.3 mi (5.3 km) northwest of Jayuya plaza. DRAINAGE AREA.--40.4 mi> (104.6 km'). PERIOD OP RECORD.--Hater years 1979 to current year. HATER-QUALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 65 Lago DATE OCT 1991 31. .. JAN 1992 07. .. FEB 27. .. APR 02. .. JUN 04. .. ADQ 25. .. TIME 1200 1315 0845 0950 1105 0940 DIS- CHARGE, INST. CUBIC FEET PER SECOND 82 E300 23 39 171 38 SPE- CIFIC CON- DUCT- ANCE (US/CM) 146 132 184 201 170 204 PH HATER WHOLE FIELD (STAND- ARD UNITS) 7.4 7.3 7.9 7.6 7.7 7.2 TEMPER- ATURE HATER (DEG C) 23.0 22.0 21.0 23.5 25.0 24.0 TUR- BID- ITY (NTU) 17 18 0.40 7.5 5.1 69 OXYGEN, DIS- SOLVED (MG/L) 8.6 9.5 9.3 9.0 8.2 6.2 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 82 100 98 95 78 58 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 21 <10 14 12 13 10 COLI- FORM, FECAL, 0.7 UM-MF (COLS./ 100 ML) 3600 2300 K36 K745 K1300 K9700 STREP- TOCOCCI FECAL, KF AGAR (COLS. PER 100 ML) 2100 4100 82 360 360 4300 DATE OCT 1991 31. .. JAN 1992 07. . . FBB 27. .. APR 02. .. JUN 04. .. AUG 25. .. HARD- NESS TOTAL (MG/L AS HARD- NESS NONCARB CALCIUM HH WAT TOT FLD CACO3) CACO3 53 73 79 DIS- SOLVED MG/L AS (MG/L 14 19 21 MAGNE- SIUM, DIS- SODIUM, DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS NA) SODIUM AD- SORP- TION RATIO 6.2 11 6.5 14 POTAS- SIUM, DIS- SOLVED (MG/L AS K) ALKA- LINITY HAT HH TOT FET FIELD MG/L AS CAC03 SULFIDE TOTAL (MG/L AS S) SULFATE DIS- SOLVED (MG/L AS S04) CHLO- RIDE, DIS- SOLVED (MG/L AS CL) 4.5 8.1 0.5 1.8 0.6 3.1 0.7 1.8 48 32 75 69 53 70 <0.5 11 <0.5 14 13 9.4 12 9.3 SOLIDS, RESIDUE FLUO- SILICA, RIDE, DIS- DIS- SOLVED SOLVED (MG/L DATE (MG/L AS AS P) SI02) OCT 1991 31... <0.10 20 JAN 1992 07... FEB 27... APR 02... <0.10 22 JUN 04... AUG 25... <0.10 23 B = estimate K = non- ideal count SUM OF SOLIDS, TOTAL CONSTI- DIS- AT 105 TUENTS, SOLVED DBG. C, DIS- (TONS SUS- SOLVBD PER FENDED (MG/L) DAY) (MG/L) 98 21.7 12 17 1 129 13.5 1 12 133 13.6 82 NITRO- NITRO- GEN, GEN, NITRATE NITRITE TOTAL TOTAL (MG/L (MG/L AS N) AS N) 0.660 0.010 1.17 0.030 <0.010 <0.010 <0.010 0.510 0.070 NITRO- GEN, N02+N03 TOTAL (MG/L AS 0 1 0 0 1 0 N) .670 .20 .360 .570 .10 .580 NITRO- GEN, AMMONIA TOTAL (MG/L AS 0 0 0 0 <0 0 N) .030 .030 .020 .020 .010 .090 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.27 0.27 — -- -- -- 66 RIO GRANDE OB ARBCIBO BASIN 50026050 RIO CAONILLAS ABOVE LAOO CAONILLAS NEAR JAYTJYA, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 31... JAN 1992 07... FEB 27... APR 02... •TON 04.. . AUG 25... DATE OCT 1991 31... JAN 1992 07... FBB 27.. . APR 02... •TON 04.. . AUG 25... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.30 0.30 <0.20 <0.20 <0.20 <0.20 IRON, TOTAL RECOV- ERABLE (OG/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) 0.97 1.5 — — — -- LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS NO3) 4.3 6.6 -- -- -- -- MANGA- NESE, TOTAL RECOV- ERABLE (OG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.070 0.070 0.060 0.060 0.050 0.080 MERCURY TOTAL RECOV- ERABLE (OG/L AS HG) ARSENIC TOTAL (UG/L AS AS) <1 -- -- <1 -- -- SELE- NIUM, TOTAL (OG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 — — <100 — — SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) 20 -- -- <10 -- -- ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 — — <1 — — CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) <1 — -- <1 -- -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CO) 40 -- — <10 — -- METHY- LENB BLUE ACTIVE SUB- STANCE (MG/L) 1200 610 60 40 <0.10 <0.10 <0.010 <0.010 0.03 0.02 RIO QRANDB DB ARBCIBO BASIN QJ 50026140 LAQO CAONILLAS AT CACHILLAS, PR LOCATION.--Lat 18°16'43", long 66°39'43-, Hydrologic Unit 21010001, at Lago Caonillas Dam on Rio Caonillas, 2.92 mi (4.7 km) northeast of Plaza da Utuado, 0.34 mi (0.55 km) tract from Iglesia Santa Maria del Monte Carmelo, and 1,85 mi (3.0 km) nothwest from Hacienda Carbonell. DRAINAQB AREA.--48.4 mi' (125.4 km*). ELEVATION RECORDS PERIOD OF RECORD.--March 1991 to current year. GAGE.—Water stage recorder. Datum of gage is mean sea level. REMARKS.--Lago Caonillas was completed in 1948. The dam is a concrete gravity structure with a total length of 815 ft (248 m), a maximum height of 235 ft (72 m), and a maximum base width of 195 ft (59 m). Nonoverflow sections on each abutment have a total length of 603 ft (184 m). The dam is the main unit of Caonillas Hidroelectric Project, and provides 49,000 acre-feet (60 hm?) of usable storage for power generation at Caonillas Power Plant No. 1 located 2.5 mi (4.0 km) downstream from the dam. The dam is owned by Puerto Rico Electric Power Authority. Gage-height and precipitation satellite telemetry at station. EXTREMES FOR PERIOD OF RECORD.--Maximum elevation 824.46 ft (286.91 m), June 3; minimun elevation, less than 771.00 ft (235.00 m), many days. Capacity Table (based on data from Puerto Rico Electric Power Authority) Elevation, in feet Contents, in acre-feet Elevation, in feet Contents, in acre-feet 705 0 800 27,982 750 8,421 830 46,161 ELEVATION (FEET NGVD), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY OBSERVATION AT 24:00 VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 780.74 785.97 787.65 788.05 805.98 805.97 A 804.83 823.23 809.95 791.88 784.62 2 780.98 786.32 787.17 787.92 806.02 805.84 805.66 804.93 824.22 809.41 791.29 784.85 3 781.17 786.54 787.26 787.78 806.12 805.82 806.35 804.76 824.11 808.89 790.17 784.97 4 781.28 786.71 787.28 787.82 806.16 805.81 806.39 804.54 824.12 808.67 788.83 785.11 5 781.45 786.93 787.27 790.71 806.19 805.74 806.51 803.86 824.20 808.32 788.87 784.50 6 781.62 786.98 787.26 804.60 806.13 805.73 806.42 803.28 823.87 807.53 788.11 784.72 7 781.76 787.16 787.27 805.85 806.44 805.72 806.57 802.90 822.56 807.11 787.04 786.55 8 781.99 787.38 787.28 805.75 806.53 806.17 806.69 802.27 823.18 806.38 787.13 787.28 9 782.00 787.59 787.37 805.96 806.61 806.31 807.06 802.27 822.76 805.35 787.27 787.63 10 782.14 787.09 787.44 805.44 806.69 806.02 807.45 802.26 822.39 804.20 788.04 787.90 11 782.28 787.17 787.50 805.52 806.47 805.99 807.41 801.70 822.10 803.48 788.25 787.21 12 782.19 787.35 787.57 805.57 806.34 805.32 807.52 801.79 821.33 802.83 788.54 787.17 13 782.18 786.28 787.65 805.59 806.36 804.63 807.61 801.84 820.83 802.33 788.50 787.35 14 782.31 786.21 787.57 805.82 806.41 804.41 807.62 800.84 820.48 801.61 788.64 787.52 15 782.44 786.37 787.63 805.59 806.47 803.25 807.75 800.10 819.76 800.98 788.61 788.53 16 782.57 786.52 787.72 805.59 806.51 803.38 807.68 800.31 819.07 800.23 788.37 789.12 17 782.69 786.48 787.73 805.78 806.48 802.84 807.77 800.80 818.32 799.65 788.15 788.75 18 783.12 786.53 787.75 805.79 806.48 802.90 807.68 801.14 817.39 799.04 787.97 788.95 19 783.48 786.63 787.82 805.77 806.48 801.98 808.31 801.00 816.79 798.67 787.40 788.64 20 783.64 786.55 788.01 805.78 806.48 800.75 809.16 801.86 814.89 798.28 786.52 789.12 21 783.76 786.51 788.40 805.85 806.43 801.17 808.71 801.79 814.22 797.71 785.66 789.12 22 783.97 786.62 788.57 805.91 806.44 801.17 807.96 801.40 814.66 797.06 784.72 789.21 23 783.56 786.73 788.71 805.43 806.44 801.09 807.66 809.65 813.70 796.49 784.71 790.07 24 782.93 786.88 788.81 805.47 806.30 801.09 807.09 812.88 813.21 795.91 784.49 790.58 25 782.67 787.00 788.91 805.53 806.19 801.52 807.00 814.67 812.70 795.95 784.64 790.61 26 782.77 787.12 788.72 805.58 806.18 801.60 807.06 817.10 812.11 795.95 784.73 790.87 27 782.85 787.24 788.61 805.63 806.18 801.25 806.46 818.25 811.67 795.58 784.72 791.01 28 782.71 787.34 788.48 805.76 806.17 801.60 805.88 818.65 811.51 794.58 784.93 791.40 29 783.45 787.44 788.18 805.90 806.10 801.92 805.37 819.53 810.83 793.48 785.10 791.69 30 784.48 787.55 788.09 806.03 —— A 805.13 820.16 810.47 792.62 785.24 792.23 31 785.20 —— 787.91 806.05 —— A —- 821.56 —— 792.56 784.39 —— TOTAL24260.38 23605.19 24423.59 24889.82 23383.78 —— —— 25002.92 24550.68 24830.80 24402.91 23647.28 MEAN 782.59 786.84 787.86 802.90 806.34 —— —— 806.55 818.36 800.99 787.19 788.24 MAX 785.20 787.59 788.91 806.05 806.69 —— —— 821.56 824.22 809.95 791.88 792.23 MIN 780.74 785.97 787.17 787.78 805.98 —— --- 800.10 810.47 792.56 784.39 784.50 A No gage-height record. 68 RIO GRANDS DB ARBCIBO BASIN 50027250 RIO GRANDS DB ARBCIBO BELOW LAGO DOS BOCAS NEAR FLORIDA, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°20'50", long 66°40'02", at pedestrian bridge, 0.7 mi (1.1 km) downstream from Lago DOB Bocaa and 6.6 mi (10.6 km) west of Florida plaza. DRAINAGE AREA.--169 mi 1 (436 km>) does not include 6.0 mi> (15.6 km>) above Lago Garzaa. PERIOD OP RECORD.--Water years 1970-71, 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 SEPTEMBER 1992 DATE NOV 1991 05. .. DEC 30. .. FBB 1992 28. .. APR 15. .. JUN 24. .. AUG 20. .. TIME 1030 0815 0840 0900 0835 0845 DIS- CHARGE, INST. CUBIC FEET PER SECOND 26 20 20 18 16 19 SPE- CIFIC CON- DUCT- ANCE (OS/CM) 193 244 244 197 173 200 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.4 7.6 7.6 6.5 6.8 6.7 TEMPER- ATURE WATER (DBG C) 25.5 23.0 23.0 24.5 25.5 26.0 TUR- BID- ITY (NTU) 54 1.3 1.4 13 7.3 1.6 OXYGEN, DIS- SOLVED (MG/L) 5.4 6.3 6.3 6.0 5.6 4.0 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 60 78 79 71 64 52 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 13 <10 16 22 29 12 COLI- FORM, FECAL, 0.7 UM-MF (COLS./ 100 ML) 200 64 K8 54 K10 K40 STREP- TOCOCCI FECAL, KF AGAR (COLS. PER 100 ML) 400 85 K4 270 37 K120 DATE NOV 1991 05. .. DEC 30. .. FBB 1992 28. .. APR 15. . . JUN 24... AUG 20. .. HARD- NESS TOTAL (MG/L AS HARD- NESS NONCARB »H WAT TOT FLD MG/L AS CALCIUM DIS- SOLVED (MG/L MAGNE- SIUM, DIS- SOLVED (MG/L SODIUM, DIS- SOLVED (MG/L SODIUM AD- SORP- TION RATIO POTAS- SIUM, DIS- SOLVED (MG/L ALKA- LINITY WAT WH TOT FBT FIELD MG/L AS SULFIDB TOTAL (MG/L SULFATB DIS- SOLVED (MG/L CHLO- RIDE, DIS- SOLVED (MG/L CACO3) CAC03 68 76 81 AS CA) AS MG) AS NA) AS K) CAC03 AS S) AS SO4) AS CL) 19 21 22 5.1 8.8 0.5 2.5 5.7 9.7 0.5 2.6 6.3 11 0.5 2.3 64 85 85 66 62 80 <0.5 11 <0.5 14 13 11 14 13 SOLIDS, DATE NOV 1991 05.. . DEC 30... FEB 1992 28... APR 15. .. JUN 24.. . AUG 20... FLUO- RIDE, DIS- SOLVED (MG/L AS F) <0.10 -- __ 0.20 -- <0.10 SILICA, DIS- SOLVED (MG/L AS SI02) 20 -- __ 18 — 21 SUM OP CONSTI- TUENTS, DIS- SOLVED (MG/L) 116 -_ -- 125 -- 135 RESIDUE SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, SOLVED DBG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC (TONS BUS- TOTAL TOTAL TOTAL TOTAL TOTAL PER FENDED (MG/L (MG/L (MG/L (MG/L (MG/L DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) 14 1 1 30 12 10 0 0 0 0 0 .660 .500 — .630 .140 .240 0. 0. <0. 0. 0. 0. 040 010 010 020 020 020 0 0 0 0 0 0 .700 .510 .350 .650 .160 .260 0. 0. 0. 0. 0. 0. 060 020 040 040 090 080 0. — 0. — 0. 0. 34 46 11 42 non-ideal count 69 RIO GRANDB DE ARBCIBO BASIN 50027250 RIO GRANDB DB ARBCIBO BELOW LAQO DOS BOCAS NEAR FLORIDA, PR—Continued HATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE NOV 1991 05.. . DEC 30.. . FBB 1992 28.. . APR 15. .. JUN 24.. . AUG 20.. . DATE NOV 1991 05. . . DBC 30... FBB 1992 28.. . APR 15.. . JUN 24.. . AUG 20.. . NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.40 <0.20 0.50 <0.20 0.20 0.40 IRON, TOTAL RECOV- ERABLE (UG/L AS FE) 3600 -- -- 670 -- -- NITRO- GEN, TOTAL (MG/L AS N) 1.1 -- 0.85 -- 0.36 0.60 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) 3 -- -- <1 — -- NITRO- GEN, TOTAL (MG/L AS NO3) 4.9 __ 3.8 -- 1.6 2.7 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) 90 -- -- 30 -- -- PHOS- PHORUS TOTAL (MG/L AS P) 0.070 0.030 0.030 0.030 0.020 0.020 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) <0.10 -- -- 0.10 -- -- BARIUM, TOTAL ARSENIC RBCOV- TOTAL BRABLB (UG/L (UG/L AS AS) AS BA) <1 <100 __ __ <1 <100 __ __ _-. SILVER, SBLE- TOTAL NIUM, RECOV- TOTAL ERABLE (UG/L (UG/L AS SB) AS AG) <1 <1 __ __ <1 <1 __ __ CHRO- BORON, CADMIUM MIUM, TOTAL TOTAL TOTAL RBCOV- RBCOV- RECOV- ERABLE BRABLB BRABLB (UG/L (UG/L (UG/L AS B) AS CD) AS CR) 50 <1 4 __ __ 20 <1 <1 __ __ __ __ ZINC, TOTAL RECOV- CYANIDE BRABLB TOTAL PHENOLS (UG/L (MG/L TOTAL AS ZN) AS CN) (UG/L) <10 <0.010 1 __ __ <10 <0.010 1 -_ -_ COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) 70 __ -- 10 — -~ MBTHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 0.02 -- — 0.03 -- -- 70 RIO GRANDB DB ARBCIBO BASIN 50027750 RIO GRANDB DB ARBCIBO ABOVE ARBCIBO, PR LOCATION.--Lat 18°25'22", long 66°41'58", Hydrologic Unit 21010002, 0.5 mi (0.8 km) upitream from Rio Tanama, 3.6 mi (5.8 km) couth of Arecibo and 4.9 ai (7.9 km) above mouth, and 10.4 mi (16.7 km) downstream from Lago Do* Bocac. DRAINAGE AREA.--200 mi> (520 km'), approximately, of which an undetermined amount doe* not contribute directly to curface runoff. WATER-DISCHARGE RECORDS PERIOD OF RECORD.--April 1982 to current year. GAGB.—Water-«tage recorder. Elevation of gage i« 30 ft (9 m), from topographic map. REMARKS.--Record* fair except thoce for estimated daily discharge*, which are poor. Plow regulated by Lago Do* Boci Dam 10.4 mi (16.7 km) upctream from gage. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN PBB MAR APR MAY JUN JUL AUG SEP 1 87 e210 2 217 e230 3 446 e420 4 382 e450 5 94 e320 6 61 536 7 49 609 8 165 532 9 114 219 10 137 422 11 312 328 12 96 231 13 237 502 14 333 656 15 136 284 16 230 114 17 47 76 18 42 339 19 41 139 20 112 175 21 419 83 22 516 182 23 266 52 24 229 42 25 415 42 26 99 39 27 86 38 28 168 37 29 313 36 30 344 58 31 658 TOTAL 6851 7401 MEAN 221 247 MAX 658 656 MIN 41 36 AC -FT 13590 14680 CFSM 1.10 1.23 IN. 1.27 1.38 e Estimated STATISTICS OF MONTHLY MEAN MEAN 726 642 MAX 1984 1413 (WY) 1986 1986 MIN 221 247 (WY) 1992 1992 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC- FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 188 51 99 62 72 111 113 93 84 44 36 34 38 43 176 43 39 37 35 38 53 46 63 54 51 77 113 164 135 178 430 2800 90.3 430 34 5550 .45 .52 DATA 309 570 1988 90.3 1992 FOR 191 162 181 154 95 614 542 536 634 516 307 121 448 214 334 159 78 225 132 134 124 40 228 e!73 e60 e47 e212 e66 e!81 e460 e251 7619 246 634 40 15110 1.23 1.42 FOR WATER 255 437 1988 167 1989 e99 e96 e40 e33 e233 337 406 e!30 e47 e!30 223 453 135 e35 e33 e34 el20 e45 e41 e39 e37 e35 e34 el70 e80 e52 e34 34 38 ___ 3223 111 453 33 6390 .56 .60 YEARS 1982 241 428 1988 111 1992 141 e40 e37 e34 e560 e45 e38 e34 e40 87 112 e560 e740 el60 e250 e540 157 58 57 836 e!200 219 46 93 42 37 350 80 91 39 35 6758 218 1200 34 13400 1.09 1.26 - 1992 227 351 1985 114 1987 1991 CALENDAR YEAR 97499 267 1030 34 41 193400 1. 18. 535 219 58 May 11 Dec 12 Nov 23 34 13 34 35 66 109 162 295 120 74 346 805 748 245 55 46 132 130 134 49 300 543 745 862 565 541 196 81 409 354 463 191 8835 294 862 34 17520 1.47 1.64 241 83 262 185 281 282 278 432 95 51 358 292 248 405 120 84 80 566 730 576 618 828 1650 2030 993 811 906 690 588 476 569 15808 510 2030 51 31360 2.55 2.94 722 1210 737 618 519 377 574 680 638 665 669 674 643 388 625 658 692 727 825 113 302 719 674 242 120 78 64 148 199 511 --- 15811 527 1210 64 31360 2.64 2.94 422 407 350 199 222 595 236 257 271 214 358 378 591 98 61 391 408 301 314 361 450 324 341 360 90 51 216 420 447 482 126 9741 314 595 51 19320 1.57 1.81 611 597 367 478 427 351 397 89 186 548 468 123 151 133 46 255 ellO e98 e200 e300 e580 e480 e58 e400 608 485 354 81 38 33 143 9195 297 611 33 18240 1.48 1.71 65 101 436 293 311 67 38 84 440 666 653 129 68 64 89 115 316 130 313 247 145 359 210 513 593 304 92 201 403 526 --- 7971 266 666 38 15810 1.33 1.48 , BY WATER YEAR (WY) 418 617 1986 207 1984 FOR 1992 102013 279 2030 33 41 3880 9 202300 1 18 620 199 40 699 2000 1986 185 1989 WATER YEAR May 24 Feb 4 Nov 23 May 23 .03 May 23 .39 .97 398 683 1987 195 1990 280 374 1987 161 1990 WATER 415 729 279 14800 33 41 45800 18 30 300700 2 28 838 275 63 275 474 1988 154 1990 YEARS 1982 May Feb Nov May .22 May Mar .08 .20 498 1080 1984 266 1992 - 1992 1986 1992 18 1985 4 1992 23 1991 18 1985 18 1985 30 1986 71 RIO GRANDE DB ARBCIBO BASIN 50027750 RIO GRANDS DB ARECIBO ABOVE ARECIBO, PR--Continued HATER QUALITY RECORDS PERIOD OF RECORD.--HATER YEARS APRIL 1982 TO CURRENT YEAR STRBAMFLOW, SPECIFIC CON- TEMPERA- STRBAMFLOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCB TORS DATE TIME INSTANTANEOUS DUCTANCB TORE (CFS) (OMHOS) (DBG C) (CFS) (UMHOS) (DBG C) APR. 22 1125 121 230 26.0 AUG. 16 0930 92 242 22.5 JUN. 25 1145 43 273 28.0 '*• RIO GRANDB DB ARBCIBO BASIN 50028000 RIO TANAMA NEAR UTUADO, PR LOCATION.--Lat 18°18'02", long 66°46'58", Hydrologic Unit 21010001, on downstream side of left abutment of bridge on Highway 111, 1.2 mi (1.9 km) upstream from natural tunnel, 1.5 mi (2.4 km) northeast of Angeles, and 5.8 mi (9.3 km) northwest of Utuado. DRAINAGE AREA.--18.4 mi' (47.7 km'). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—June 1944 to June 1958 (daily stage and two to four measurements per month by Puerto Rico Water Resources Authority), November 1959 to current year. GAGE.--Water-stage recorder and crest-stage gage. Datum of gage is 938.32 ft (286.000 m) above mean sea level. Datum of gage was lowered 3.00 ft (0.914 m) on Oct. 1978. Prior to Nov. 17, 1966, non-recording gage and Nov. 17, 1966 to Sept. 30, 1978 recording gage, both at present site. REMARKS.--Records fair except those for estimated daily discharges, which are poor. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR MAY JUN JUL AUG SEP 1 52 73 2 40 57 3 36 51 4 35 48 5 34 45 6 34 44 7 34 43 8 91 41 9 49 39 10 40 38 11 36 37 12 34 36 13 36 36 14 34 35 15 34 35 16 32 35 17 30 34 18 76 33 19 118 33 20 103 32 21 109 32 22 139 32 23 82 31 24 e63 32 25 e56 31 26 50 30 27 46 31 28 59 28 29 71 28 30 80 27 31 124 --- TOTAL 1857 1127 MEAN 59.9 37.6 MAX 139 73 MIN 30 27 AC-FT 3680 2240 CFSM 3.26 2.04 IN. 3.75 2.28 e Estimated STATISTICS OF MONTHLY MEAN MEAN 80.7 70.5 MAX 195 159 (WY) 1990 1969 MIN 25.4 29.3 (WY) 1963 1979 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN- DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 26 26 26 26 25 24 24 24 24 24 23 23 22 24 22 22 22 22 21 37 35 24 23 22 21 21 21 21 21 21 22 739 23.8 37 21 1470 1.30 1.49 DATA 43.3 121 1966 21.5 1965 FOR 21 20 19 19 25 203 e34 26 25 23 25 26 24 22 21 21 21 20 19 19 18 18 18 19 18 19 18 19 19 19 19 837 27.0 203 18 1660 1.47 1.69 FOR WATER 29.4 50.1 1966 18.0 1974 18 17 16 16 16 17 19 17 16 15 14 15 15 15 15 14 14 14 14 14 13 13 13 13 13 13 13 12 12 __. --- 426 14.7 19 12 845 .80 .86 YEARS 1960 25.2 40.5 1961 13.2 1965 12 12 12 11 11 11 18 26 21 20 19 13 12 12 12 11 15 14 12 11 10 10 9.9 9.6 33 22 15 74 180 e50 47 745.5 24.0 180 9.6 1480 1.31 1.51 - 1992 24.8 71.2 1972 11.0 1984 1991 CALENDAR YEAR 15176 41. 338 11 12 30100 2. 30. 74 34 17 6 May 5 Mar 15 Mar 13 26 68 41 e28 e24 e20 18 21 29 25 59 65 35 30 27 23 24 47 40 27 88 45 33 31 28 26 25 24 24 23 23 25 --- 978 32.6 88 18 1940 1.77 1.98 27 37 26 24 23 23 23 22 21 21 45 80 37 28 26 58 49 99 194 e85 e84 54 199 132 101 100 74 62 76 59 91 1980 63.9 199 21 3930 3.47 4.00 223 99 74 e66 e58 55 72 133 e65 91 63 51 45 41 40 38 37 35 34 34 33 32 30 29 27 27 26 25 24 23 1630 54.3 223 23 3230 2.95 3.30 22 22 23 22 23 25 26 34 28 26 45 31 27 33 32 27 27 30 38 78 46 36 30 57 46 32 66 38 32 41 101 1144 36.9 101 22 2270 2.01 2.31 47 36 32 69 55 92 57 59 52 45 41 37 44 39 35 34 35 33 32 34 55 63 72 42 72 49 42 36 34 33 32 1438 46.4 92 32 2850 2.52 2.91 124 e61 42 39 43 45 85 75 47 74 48 44 43 43 42 42 42 41 42 84 45 46 48 41 38 37 36 52 52 135 1636 54.5 135 36 3250 2.96 3.31 , BY WATER YEAR (WY) 37.4 142 1969 9.70 1984 FOR 1992 14537. 39. 223 9. 11 3490 12. 9. 28840 2. 29. 74 32 15 59.2 193 1963 12.4 1977 WATER YEAR 5 7 Jun 1 6 Mar 24 Mar 18 Jan 6 46 Jan 6 4 Mar 24 16 39 43.2 116 1979 16.5 1977 37.9 65.7 1981 19.5 1976 WATER 47 71 29 2170 6 7 12200 17 6 34710 2 35 84 33 17 47.6 110 1979 24.3 1976 YEARS 1960 - .9 .1 .9 May 17 .5 May 12 .4 May 6 May 18 .45 May 18 .6 Jun 12 .60 .38 74.7 177 1961 27.6 1986 1992 1969 1983 1963 1984 1984 1985 1985 1977 73 RIO GRANDB DB ARECIBO BASIN 50028000 RIO TANAMA NEAR UTUADO, PR—Continued WATER-QUALITY RECORDS PERIOD OP RECORD.--Water years 1958 to current year. PERIOD OP DAILY RECORD.-- SUSPENDED SEDIMENT DISCHARGE: January 1968 to current year. INSTRUMENTATION.--US D-49 SEDIMENT SAMPLER SINCE OCTOBER 1968. AUTOMATIC SEDIMENT SAMPLER SINCE 1990 REMARKS.--Sediment samples were collected by a local observer on a weekly basis and during high flow events. Estimates for period of missing daily record were made from a sediment transport curve developed from a period of record over 5 years. EXTREMES POR PERIOD OP DAILY RECORD.-- SEDIMENT CONCENTRATIONS: Maximum daily mean, 20,400 mg/L November 27, 1968; minimum daily mean, 0 mg/L during water year 1985. SEDIMENT LOADS: Maximum daily, 167,000 tons (152,000 tonnes) May 18, 1985, minimum daily, 0.0 ton (0.0 tonne) several days during many years. EXTREMES FOR CURRENT YEAR,-- SEDIMENT CONCENTRATIONS: Maximum daily mean, 1,900 mg/L October 1, 1990; minimum daily mean, 3.0 mg/L several days. SEDIMENT LOADS: Maximum daily, 16,500 tons (15,000 tonnes) October 17, 1989; minimum daily 0.14 ton (0.13 tonne) several days. WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 21. .. DEC 17. .. PBB 1992 18. . . APR 09. . . JUL 08. .. SEP 03. .. TIME 1310 1030 1200 1020 0840 1055 DIS- CHARGE, INST. CUBIC PBBT PER SECOND 55 23 13 22 26 43 SPE- CIFIC CON- DUCT- ANCE (US/CM) 142 146 175 156 167 154 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.5 7.8 7.7 7.5 6.8 7.1 TEMPER- ATURE WATER (DBG C) 22.5 20.5 22.0 23.0 24.5 27.0 TUR- BID- ITY (NTU) 24 1.9 1.2 5.9 2.1 10 OXYGEN, DIS- SOLVED (MG/L) 8.9 6.4 8.8 9.8 8.4 7.1 OXYGEN, OXYGEN DIS- DEMAND, SOLVED CHEM- (PBR- ICAL CENT (HIGH SATUR- LEVEL) ATI ON) (MG/L) 102 <10 80 <10 99 <10 106 <10 90 <10 84 <10 COLI- FORM, FECAL, 0.7 UM-MF (COLS./ 100 ML) 2000 97 22 K16000 270 K590 STREP- TOCOCCI FECAL, KP AGAR (COLS. PER 100 ML) 1000 220 110 K2000 — K110 DATE OCT 1991 21. .. DEC 17. .. PBB 1992 18. .. APR 09... JUL 08. .. SBP 03. .. HARD- NESS TOTAL (MG/L AS CACO3) HARD- NESS NONCARB WH WAT TOT PLD MG/L AS CAC03 CALCIUM DIS- SOLVED (MG/L AS CA) MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) SODIUM, DIS- SOLVED (MG/L AS NA) 53 4 13 62 7 16 61 5 16 SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY SIUM, WAT WH DIS- SOLVED AS K) 4.9 7.5 0.4 2.2 5.3 7.6 0.4 2.4 5.1 7.7 0.4 2.0 CHLO- SULFATB RIDE, TOT PET SULPIDB DIS- DIS- PIBLD TOTAL SOLVED SOLVED (MG/L MG/L AS (MG/L CACO3 38 49 52 48 54 94 (MG/L <0.5 12 <0.5 15 12 (MG/L AS S) AS S04) AS CL) 6.6 12 8.2 non-ideal count 74 RIO GRANDB DB ARBCIBO BASIN 50028000 RIO TANAMA NEAR UTUADO, PR--Continued HATER-QUALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- DATE OCT 1991 21.. . DEC 17.. . FEB 1992 18.. . APR 09.. . JUL 08.. . SEP 03... DATE OCT 1991 21... DEC 17.. . FEB 1992 18... APR 09.. . JUL 08.. . SEP 03... DATE OCT 1991 21... DEC 17.. . FEB 1992 18.. . APR 09... JUL 08... SEP 03.. . RIDE, DIS- SOLVED (MG/L AS F) •eO.10 -- -- 0.20 -- •eO.10 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) <0.20 <0.20 0.20 <0.20 -- <0.20 IRON, TOTAL RECOV- ERABLE (UG/L AS FE) 2200 -- -- 490 -- . DIS- SOLVED (MG/L AS SI02) 20 -- -- 24 -- 22 NITRO- GEN, TOTAL (MG/L AS N) -- -- 0.90 -- -- - - LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) 2 -- -- •el -- -- CONSTI- TUENTS, DIS- SOLVED (MG/L) 89 -- -- 111 -- 105 NITRO- GEN, TOTAL (MG/L AS N03) -- -- 4.0 -- -- - - MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) 100 -- -- 40 -- -- DIS- SOLVED (TONS PER DAY) 13.2 -- -- 6.59 -- 12.2 PHOS- PHORUS TOTAL (MG/L AS P) 0.040 0.020 0.040 •eO.010 __ 0.020 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) •eO.10 -- -- •eO.10 -- -- AT 105 DBG. C, SUS- PENDED (MG/L) 19 1 7 14 16 •el ARSENIC TOTAL (UG/L AS AS) •el -- -- •el __ - - SELE- NIUM, TOTAL (UG/L AS SB) •el -- -- •el -- -- GEN, NITRATE TOTAL (MG/L AS N) 0.780 0.670 -- 0.650 0.690 -- BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) •elOO -- -- •clOO __ - - SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) <1 -- -- <1 -- -- GEN, NITRITE TOTAL (MG/L AS N) 0.020 0.010 •eO.010 0.020 0.010 •cO.010 BORON, TOTAL RECOV- ERABLE (UG/L AS B) 10 -- -- •elO -- - - ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) •elO -- -- <10 -- -- GEN, NO2+NO3 TOTAL (MG/L AS N) 0.800 0.680 0.590 0.670 0.700 0.890 CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 -- -- •el -- - - CYANIDE TOTAL (MG/L AS CN) <0.010 -- -- •cO.010 -- — OEN, AMMONIA TOTAL (MG/L AS N) 0.040 0.010 0.020 0.040 0.020 0.010 CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) 3 -- -- •el -- " PHENOLS TOTAL (UG/L) 2 -- -- 2 -- -- GEN, ORGANIC TOTAL (MG/L AS N) -- -- — -- 0.18 — - COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) 20 -- -- 10 -- " METHY- LBNB BLUE ACTIVE SUB- STANCE (MG/L) 0.02 -- -- 0.03 -- -- 75 RIO GRANDB DB ARBCIBO BASIN 50028000 RIO TANAMA NEAR OTUADO, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/ DAY) OCTOBER 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 52 40 36 35 34 34 34 91 49 40 36 34 36 34 34 32 30 76 118 103 109 139 82 e63 e56 50 46 59 71 80 124 65 27 21 20 17 11 9 315 38 21 20 19 14 10 8 6 5 279 448 515 360 492 114 38 30 38 35 83 140 141 393 18 3.1 2.0 1.9 1.5 1.0 .85 404 5.7 2.4 1.9 1.7 1.4 .92 .75 .56 .40 243 499 273 387 598 27 e6.9 e4.4 4.9 4.4 25 64 46 362 NOVEMBER 73 57 51 48 45 44 43 41 39 38 37 36 36 35 35 35 34 33 33 32 32 32 31 32 31 30 31 28 28 27 97 40 12 7 5 4 5 6 7 7 6 6 6 6 6 6 6 6 5 3 3 3 4 4 4 5 5 5 6 6 21 6.7 1.7 .92 .63 .49 .58 .66 .75 .71 .64 .58 .58 .57 .56 .56 .55 .53 .43 .30 .26 .29 .33 .34 .37 .40 .39 .43 .46 .43 MEAN DISCHARGE (CPS) 26 26 26 26 25 24 24 24 24 24 23 23 22 24 22 22 22 22 21 37 35 24 23 22 21 21 21 21 21 21 22 MEAN CONCEN- TRATION (MG/L) DECEMBER 6 6 7 7 5 4 3 3 5 5 29 28 8 5 4 6 9 11 12 12 10 7 SEDIMENT DISCHARGE (TONS/ DAY) .42 .45 .51 .47 .33 .26 .22 .22 .25 .24 .24 .24 .24 .24 .24 .24 .27 .30 .29 4.8 3.6 .55 .31 .27 .39 .52 .62 .68 .66 .57 .43 TOTAL 1857 2992.68 1127 43.14 739 19.07 e Estimated 76 RIO GRANDE DE ARECIBO BASIN 50028000 RIO TANAMA NEAR UTUADO, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DAY (CPS) (MG/L) (TONS/DAY) (CFS) (MG/L) (TONS/DAY) JANUARY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 21 20 19 19 25 203 e34 26 25 23 25 26 24 22 21 21 21 20 19 19 18 18 18 19 18 19 18 19 19 19 19 5 4 4 5 12 481 29 12 10 8 7 10 12 13 12 8 5 4 3 3 3 2 2 4 6 .31 .23 .23 .28 1.0 1190 e3.0 .83 .63 .51 .48 .70 .74 .79 .67 .46 .29 .21 .20 .21 .21 .20 .20 .20 .18 .15 .14 .12 .13 .21 .30 FEBRUARY 18 17 16 16 16 17 19 17 16 15 14 15 15 15 15 14 14 14 14 14 13 13 13 13 13 13 13 12 12 ___ __- 7 7 5 5 5 5 5 6 7 8 7 6 5 25 4 5 6 6 5 5 4 3 2 __. _._ .36 .32 .24 .22 .22 .24 .27 .29 .32 .32 .29 .25 .21 .18 .16 .16 .16 .15 .14 .86 .14 .18 .22 .22 .20 .18 .15 .11 .08 ___ -_. MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MARCH 12 12 12 11 11 11 18 26 21 20 19 13 12 12 12 11 15 14 12 11 10 10 9.9 9.6 33 22 15 74 180 e50 47 2 2 2 2 3 4 9 29 11 7 9 6 6 5 4 4 4 4 3 3 3 2 2 2 47 8 5 293 868 86 77 .06 .06 .06 .07 .10 .13 .62 6.9 .67 .60 .52 .21 .20 .18 .14 .12 .15 .15 .11 .09 .08 .06 .06 .06 16 .58 .25 252 2810 e!2 20 TOTAL 837 1203.81 426 6.84 745.5 3122.23 e Estimated RIO GRANDE DE ARBCIBO BASIN 50028000 RIO TANAMA NEAR OTOADO, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 77 MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCBN- SEDIMENT MEAN DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DISCHARGE DAY (CPS) (MG/L) (TONS/DAY) (CPS) (MG/L) (TONS/DAY) (CPS) 1 2 3 4 S 6 7 8 9 10 11 12 13 14 IS 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 41 e28 e24 e20 18 21 29 25 59 65 35 30 27 23 24 47 40 27 88 45 33 31 28 26 25 24 24 23 23 25 --- APRIL 35 19 17 13 10 8 8 8 129 96 25 13 11 10 11 75 31 13 301 45 21 19 22 23 20 IS 11 9 8 9 ___ MAY 5. el. el. e. • . . 62 24 2. 1. 30 4. 1. 321 6. 1. 1. 1. 1. 1. . , - 0 4 1 66 49 48 58 57 8 1 85 59 78 7 0 0 9 6 7 6 3 94 67 55 52 56 -- 27 37 26 24 23 23 23 22 21 21 45 80 37 28 26 58 49 99 194 e85 e84 54 199 132 101 100 74 62 76 59 91 10 10 10 10 10 10 8 6 4 4 67 451 33 16 14 85 64 561 1070 124 143 54 1070 309 185 176 40 19 105 87 229 21 372 3 1 23 18 546 1820 e35 eS6 8 827 129 55 56 8 3 38 16 161 .75 .97 .70 .63 .62 .59 .49 .36 .26 .27 .9 .2 .94 .6 .4 .1 223 99 74 e66 eS8 55 72 133 e6S 91 63 51 45 41 40 38 37 35 34 34 33 32 30 29 27 27 26 25 24 23 ___ MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) JUNE 1010 257 56 28 18 12 100 517 79 217 69 29 27 24 21 17 14 12 10 8 7 7 8 10 10 10 10 8 7 7 4060 80 11 eS.O e2.8 1.8 46 1030 el6 114 14 4.1 3.2 2.6 2.2 1.8 1.4 1.1 .86 .72 .65 .58 .63 .74 .75 .70 .64 .53 .44 .45 _._ TOTAL 978 476.44 1980 4204.78 1630 5404.69 e Estimated 78 RIO GRANDB DB ARBCIBO BASIN 50028000 RIO TANAMA NEAR DTDADO, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL YEAR 22 22 23 22 23 25 26 34 28 26 45 31 27 33 32 27 27 30 38 78 46 36 30 57 46 32 66 38 32 41 101 1144 14537.5 JULY 8 9 11 14 17 18 18 25 14 13 55 23 17 22 31 23 14 17 30 200 33 12 12 106 53 22 183 24 18 38 341 —— MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AUGUST .48 .52 .62 .77 1.0 1.2 1.2 2.7 1.1 .92 15 2.1 1.2 3.0 3.0 1.6 .95 1.4 4.6 133 4.4 1.1 .91 49 8.3 1.9 144 2.7 1.5 7.0 351 748.17 22228.63 47 36 32 69 55 92 57 59 52 45 41 37 44 39 35 34 35 33 32 34 55 63 72 42 72 49 42 36 34 33 32 1438 38 22 20 179 £5 229 74 81 51 25 20 14 35 40 28 16 17 20 21 21 118 190 121 46 906 47 27 19 17 17 16 —— 5.2 2.2 1.8 124 14 124 12 25 8.2 3.3 2.2 1.4 9.1 4.5 2.7 1.4 1.6 1.8 1.8 1.7 39 55 41 5.7 442 7.8 3.0 1.8 1.6 1.5 1.4 947.7 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) SEPTEMBER 124 e61 42 39 43 45 85 75 47 74 48 44 43 43 42 42 42 41 42 84 45 46 48 41 38 37 36 52 52 135 ___ 1636 731 71 30 27 26 32 386 123 41 205 44 29 22 20 17 14 21 48 66 293 48 41 34 31 25 15 10 78 61 1030 ___ —— 1150 e!4 3.5 2.8 3.0 4.1 275 39 5.6 149 £.2 3.4 2.6 2.3 1.8 1.5 3.2 5.6 16 160 6.6 £.5 4.0 3.4 2.5 1.5 .98 33 12 1140 ___ 3059.08 e Estimated RIO GRANDE DE ARECIBO BASIN 50028000 RIO TANAMA NEAR UTUADO, PR--Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 79 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT MAY i: 2: JUN 0 JUL 3 SEP DATE OCT 1991 18... 20... 31... JAN 1992 06... MAY 12. .. 23. .. JUN 01... JUL 31... SEP 01... 07. .. 19. .. 30.. . LTB 1991 ). .. ). .. L. .. 1992 t. .. 1. . . L. .. L . . • L. . . f. . . >. . . ). . . TIME 1610 1900 1543 0220 1630 0915 1645 1445 1550 1728 2355 1610 SED. SUSP. FALL DIAM. PERCENT FINER THAN .016 MM 27 47 53 17 63 59 53 55 39 61 58 50 DIS- CHARGE, INST. CUBIC FEET PER SECOND 292 197 240 1330 545 289 3400 535 988 300 254 821 SED. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM 39 62 64 25 73 64 65 66 50 72 65 56 SEDI- MENT, SUS- PENDED (MG/L) 7490 3780 3220 16000 4070 1830 7830 3720 7160 3700 2320 10100 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 58 81 83 39 87 92 80 77 60 91 79 70 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 5900 2010 2090 56300 5990 1430 71900 5370 19100 3000 1590 22400 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 75 92 93 54 95 97 90 83 72 97 91 85 SED. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM 7 12 19 3 28 42 24 30 21 36 36 20 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 89 97 98 77 98 99 96 97 84 98 97 93 SED. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM 12 24 26 7 39 48 35 36 23 41 43 29 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 98 99 99 93 99 99.7 99 99 94 99 99 97 SED. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 17 32 37 11 48 42 42 44 32 48 50 37 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 99 99.5 99.6 99 100 99.8 99.8 99.8 99 100 100 99 80 RIO GRANDB DB ARECIBO BASIN 50028000 RIO TANAMA NEAR DTDADO--Continued HATER QUALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT DATE OCT 1991 18.. . 20.. . 20... 22.. . 31.. . 31.. . DEC 02.. . MAR 1992 30.. . APR 09. . . 15.. . MAY 12.. . 18.. . 18.. . 18... 18... 23... 23... JDN 02.. . JDL 31. . . ADG 25.. . 25.. . 25.. . SEP 01.. . 01.. . 07. .. 20.. . 30. . . 30. . . TIME 1625 1716 2015 1638 1618 1808 1310 1256 0816 1920 1610 1028 1840 1920 2020 0800 0855 0837 1340 1623 1648 1928 1550 1730 2100 0115 0802 1520 STREAM- FLOW, INSTAN- TANEOUS (CFS) 457 361 130 353 661 246 23 79 22 231 389 40 471 540 290 215 274 102 272 255 493 107 330 419 253 210 46 455 SEDI- MENT, SDS- PENDBD (MG/L) 3340 911 3240 2500 3070 1440 30 70 131 1770 2610 255 2410 4830 2690 4430 1660 268 2550 1540 3100 3900 1650 4290 2100 1800 368 3610 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 4120 888 1140 2390 5480 957 1.9 15 7.8 1100 2740 27.6 3070 7050 2100 2572 1230 101 1870 1060 4120 1130 1470 4860 1430 1020 46 4440 SBD. SDSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 83 86 94 80 72 84 85 91 96 91 85 98 84 81 93 74 84 69 58 72 81 93 79 90 79 92 99 81 81 RIO GRANDS DB ARBCIBO BASIN 50028400 RIO TANAMA AT CHARCO HONDO, PR LOCATION.--Lat 18°24'52", long 66°42'52", Hydrologic Unit 21010002 on right bank at abandoned power house at Charco Hondo, 1.5 mi (2.4 km) upstream from mouth, and 4 mi (6 km) south of Arecibo. DRAINAGE AREA.--57.6 mi 1 (149.2 km1 ). WATER-DISCHARGE RECORDS PERIOD OP RECORD.--April 1969 to June 1971, October 1981 to current year. GAGE.--Water-stage recorder and crest-stage gage. Elevation of gage is 60 ft (18 m), from topographic map. REMARKS.--Records poor. Diversion 0.8 mi (1.3 km) upstream for municipal supply of Arecibo. DISCHARGE, CUBIC PBBT PER SECOND, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JON JUL ADO SEP 1 95 283 2 95 176 3 83 ellO 4 79 e98 5 76 e92 6 74 e87 7 77 e96 8 131 e!25 9 119 e94 10 106 e82 11 90 e78 12 84 e74 13 82 e71 14 110 e69 15 82 e68 16 77 e68 17 74 e67 18 112 e65 19 195 e64 20 213 e63 21 229 e62 22 234 e62 23 181 e61 24 113 e60 25 96 e62 26 91 e58 27 91 57 28 95 57 29 100 57 30 164 54 31 257 TOTAL 3705 2520 MEAN 120 84.0 MAX 257 283 MIN 74 54 AC-FT 7350 5000 CPSM 2.07 1.46 IN. 2.39 1.63 e Estimated STATISTICS OP MONTHLY MEAN MEAN 171 144 MAX 335 260 (WY) 1990 1982 MIN 72.1 71.5 (WY) 1983 1988 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN- DAY MINIMUM INSTANTANEOUS PEAK PLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW PLOW ANNUAL RUNOPP (AC- FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 53 54 53 53 52 51 50 50 50 50 49 49 48 50 48 47 49 47 46 52 100 56 51 48 47 46 46 46 46 45 45 1577 50.9 100 45 3130 .88 1.02 DATA 79.2 219 1982 36.4 1989 FOR 49 46 44 43 106 e288 e!50 e70 e58 e55 55 65 56 52 49 48 48 47 46 45 44 44 44 44 44 45 43 43 43 42 42 1898 61.2 288 42 3760 1.06 1.23 FOR WATER 53.0 90.8 1982 22.3 1989 41 40 42 51 42 41 43 41 39 39 38 38 37 37 37 37 37 36 36 36 34 34 34 35 35 36 35 34 34 --- 1099 37.9 51 34 2180 .66 .71 YEARS 1969 44.9 85.1 1971 16.7 1989 33 32 32 32 32 31 34 40 55 33 42 32 30 29 29 30 32 36 30 31 31 31 31 31 46 98 36 73 358 209 76 1697 54.7 356 29 3370 .95 1.10 - 1992 39.2 70.0 1971 16.6 1966 1991 CALENDAR YEAR 32091 87. 479 35 36 63650 1. 20. 154 69 41 9 May 5 Apr 22 Apr IB 53 73 e97 e70 e54 e45 e43 e47 e64 e56 e!20 166 272 e!20 e70 e60 e90 77 69 82 144 el!5 e60 e70 e63 e56 e55 e54 e52 e50 e50 e55 --- 2466 82.3 272 43 4900 1.43 1.59 e60 e80 e62 e53 e50 e50 e50 e48 e47 e47 e90 e!70 elOl e62 e57 e75 90 148 366 239 e212 229 483 407 235 273 198 148 166 148 224 4668 151 483 47 9260 2.61 3.01 412 236 e!50 e!30 e!20 ellS el50 e270 e!40 e!90 e!50 e!20 ellO elOO e90 e86 e62 73 70 66 67 66 65 66 66 67 66 66 66 65 3524 117 412 65 6990 2.04 2.26 67 67 67 74 65 67 65 67 71 67 76 60 66 66 73 70 70 69 73 132 110 96 71 e56 112 63 92 69 61 56 251 2537 61.6 251 56 5030 1.42 1.64 325 117 66 67 102 126 102 69 93 70 56 51 43 62 44 44 e45 49 45 43 57 73 115 144 106 96 100 70 56 52 49 2563 62.7 325 43 5060 1.44 1.66 165 123 66 61 56 66 104 152 104 111 102 66 59 e76 e90 107 73 67 63 207 116 69 101 127 76 83 63 59 94 160 2692 96.4 207 56 5740 1.67 1.67 , BY WATER YEAR (WY) 70.9 141 1986 25.9 1969 FOR 1992 31146 65. 463 29 31 2920 11. 29 61780 1. 20. 151 66 37 139 371 1966 15.6 1969 WATER YEAR 1 May 23 Mar 14 Mar 13 Mar 29 32 Mar 29 Mar 14 46 12 69.1 179 1970 23.3 1969 70.0 120 1969 22.0 1989 WATER 66 124 51 2500 4 5 15000 17 3 63620 1 20 160 65 27 76.6 125 1991 37.4 1967 YEARS 1969 - .1 .3 Oct 7 .2 May 26 .4 May 22 May 16 .95 May 16 .3 May 26 .53 .78 114 216 1964 59.7 1966 1992 1966 1969 1965 1969 1969 1965 1965 1969 82 RIO GRANDS DB ARBCIBO BASIN 50029000 RIO GRANDS DB ARBCIBO AT CENTRAL CAMBALACHB, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°27'20", long 66°42'10", Hydrologic Unit 21010002, at bridge on unimproved (152 m) upstream from Central Cambalache, near Highway 2, 8.3 mi (13.4 km) downstream frc 1.9 mi (3.1 km) downstream from Rio Tanama , and 1.6 mi (2.6 km) southeast of Arecibo. DRAINAGE AREA.--200 mi 1 (520 km 1 )/ approximately. PERIOD OP RECORD.--Water years 1963-66, 1969 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 road, about 500 ft m Dos Bocas Reservoir, DATE OCT 1991 29... JAN 1992 08... FEB 28. .. JUN 26... AUG 19... DIS- PH CHARGE, SPB- WATER INST. CIFIC WHOLE CUBIC CON- FIELD TEMPER- TUR- FBBT DUCT- (STAND- ATURB BID- TIME PER ANCB ARD WATER ITY SECOND (US/CM) UNITS) (DBG C) (NTU) 1045 202 240 7.9 25.0 12 1115 157 258 7.6 23.5 96 0945 63 299 7.8 23.5 1.3 0945 148 276 7.7 27.5 5.0 1035 112 281 7.8 26.5 4.3 HARD- OXYGEN, OXYGEN COLI- DIS- DEMAND, PORM, STREP- SOLVED CHEM- FECAL, TOCOCCI OXYGEN, (PER- ICAL 0.45 PBCAL, DIS- CENT (HIGH UM-MP (COLS. SOLVED SATUR- LEVEL) (COLS./ PER (MG/L) ATION) (MG/L) 100 ML) 100 ML) 7.2 84 <10 K1200 310 6.8 78 14 K1200 740 8.8 96 12 230 500 7.0 80 <10 650 K180 6.3 72 <10 K7200 900 ALKA- HARD- NESS MAGNB- SODIUM POTAS- LINITY CHLO- NESS NONCARB CALCIUM SIUM, SODIUM, AD- TOTAL WH WAT DIS- DIS- DIS- SORP- SIUM, WAT WH SULPATB RIDE, DIS- TOT PET SULPIDB DIS- DIS- (MG/L TOT PLD SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE OCT 1991 29. .. JAN 1992 08. .. FEB 28. .. JUN 26. .. AUG 19... AS MG/L AS (MG/L (MG/L (MG/L RATIO CACO3) CACO3 AS CA) AS MG) AS NA) 110 -- 35 5.0 8.7 0. -- -- 120 -- 40 5.9 8.7 0. 120 -- 40 5.8 8.9 0. SOLIDS, RESIDUE PLUO- SILICA, SUM OP SOLIDS, TOTAL RIDE, DIS- CONSTI- DIS- AT 105 (MG/L MG/L AS (MG/L (MG/L (MG/L AS K) CACO3 AS S) AS SO4 ) AS CL) 4 1.9 94 <0.5 11 12 90 120 3 1.7 110 <0.5 11 10 3 1.5 120 -- 11 12 NITRO- NITRO- NITRO- NITRO- NITRO- GEN, GEN, GEN, GEN, GEN, DIS- SOLVED TUENTS, SOLVED DBG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC OCT 29 JAN 08 PBB 28 JUN 26 AUG 19 K = SOLVED (MG/L DIS- (TONS SUS- DATB (MG/L AS SOLVED PER PBNDBD AS P) SIO2) (MG/L) DAY) (MG/L) 1991 0.10 18 148 80.8 8 1992 83 1 0.30 16 160 63.8 20 0.20 16 166 50.2 11 non- ideal count TOTAL TOTAL TOTAL TOTAL TOTAL (MG/L (MG/L (MG/L (MG/L (MG/L AS N) AS N) AS N) AS N) AS N) 0.520 0.010 0.530 0.030 0.840 0.070 0.910 0.120 0.28 < 0.010 0.280 0.010 <0.010 0.560 0.030 •cO.010 0.350 0.030 RIO GRANDB DB ARBCIBO BASIN 50029000 RIO GRANDB DB ARBCIBO AT CENTRAL CAMBALACHE, PR—Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 83 DATE OCT 1991 29... JAN 1992 08... FBB 28.. . JUN 26.. . AUG 19.. . DATE OCT 1991 29.. . JAN 1992 08.. . FBB 28. . . JUN 26. . . AUG 19.. . NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) <0.20 0.40 <0.20 <0.20 <0.20 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) — 1.3 -- -- -- LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS NO3) -- 5.8 -- -- -- MANGA- NESE, TOTAL RECOV- ERABLE (OG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.040 0.120 0.030 0.020 <0.010 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) ARSENIC TOTAL (OG/L AS AS) <1 -- -- <1 -- SELE- NIUM, TOTAL (OG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 — -- <100 -- SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) 40 -- -- 20 -- ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 — — <1 -- CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) 1 -- -- <1 -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) 30 — — <10 -- MBTHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 530 330 30 60 <0. 10 <0. 10 20 <0.010 <0.010 0.03 0.01 PESTICIDE ANALYSES DATE JUN 1992 26.. . PCB, TIME TOTAL (UG/L) 0945 ALDRIN, TOTAL (UG/L) <0.010 CHLOR- DANE, TOTAL (UG/L) DDD, TOTAL (UG/L) DDE, TOTAL (UG/L) DOT, TOTAL (UG/L) DI- AZINON, TOTAL (UG/L) DI- BNDO- BLDRIN SULFAN, TOTAL TOTAL (UG/L) (UG/L) <0.010 <0.010 <0.010 <0.01 <0.010 <0.010 JUN 1992 26... JUN 1992 26.. . ENDRIN WATER UNPLTRD REC (UG/L) <0.010 PARA- THION, TOTAL (UG/L) BTHION, TOTAL (UG/L) <0.01 NAPH- THA- LENES, POLY- CHLOR. TOTAL (UG/L) HBPTA- CHLOR, TOTAL (UG/L) •cO.010 PER- THANB TOTAL (UG/L) HEPTA- CHLOR BPOXIDB TOTAL (UG/L) •cO.010 TOX- APHENB, TOTAL (UG/L) LINDANB TOTAL (UG/L) •cO.010 TOTAL TRI- THION (UG/L) MA LA- THI ON, TOTAL (UG/L) <0.01 2,4-D, TOTAL (UG/L) METH- OXY- CHLOR, TOTAL (UG/L) <0.01 2,4,5-T TOTAL (UG/L) METHYL PARA- THION, TOTAL (UG/L) <0.01 2, 4 -DP TOTAL (UG/L) MIRBX, TOTAL (UG/L) <0.01 SILVEX, TOTAL (UG/L) <0.01 <0.10 <0.01 <0.01 <0.01 <0.01 <0.01 84 THIS PAGE WAS LEFT BLANK INTENTIONALLY ATU-.NTIC OChAN ;P •v- r3S«'.- 8a»i . ^ r—Ma? onsa _ \ *?3te"~"-- 1 t- EXPLANATION A 0350 SURFACE-WATER STATION AND NUMBER Y°307 QUALITY-OF-WATER STATION AND NUMBER • 210 WELL AND WELL NUMBER • 032290 LAKE-ELEVATION STATION Figure 16.-Rio Grande de Manati basin. 86 RIO GRANDE DE MANATI BASIN 50030460 RIO OROCOVIS AT OROCOVIS, PR LOCATION.--Lat 18°13'25", long 66°23'34 > , Hydrologic Unit 21010001, on right bank, 0.4 ml (0.6 km) south of junction of Highways 155 and 156 In Orocovls, 600 ft (183 m) upstream from Rio Batijas, and 250 ft (76 m) upstream from bridge on Highway 599. DRAINAGE AREA.--5.03 mi> (13.03 km2 ). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—April 1981 to September 1982, October 1988 to current year. GAGE.—Water-stage recorder. Elevation of gage is 500 ft (152 m), from topographic map. REMARKS.--Records poor. Low flow affected by divereione for water supply. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1989 TO SEPTEMBER 1990 DAILY MEAN VALUES DAY OCT JAN FEB MAR APR MAY JUN JUL AUG SEP 1 e!85 13 2 e247 11 3 e253 10 4 elOS 10 5 e32 9.7 6 18 9.0 7 16 8.9 8 17 8.3 9 15 8.4 10 14 8.5 11 13 8.0 12 '12 7.9 13 12 9.0 14 12 8.8 15 22 7.9 16 51 7.6 17 40 7.7 18 29 7.9 19 19 7.5 20 48 7.2 21 54 7.0 22 148 7.3 23 162 7.1 24 57 6.9 25 29 6.9 26 43 7.2 27 39 7.2 28 44 6.7 29 31 • 6.8 30 18 6.7 31 14 --- TOTAL 1799 246.1 MEAN 58.0 8.20 MAX 253 13 MIN 12 6.7 AC-FT 3570 488 CFSM 11.5 1.63 IN. 13.30 1.82 e Estimated STATISTICS OF MONTHLY MEAN MEAN 28.1 7.05 MAX 58.0 9.57 (WY) 1990 1982 MIN 7.40 3.38 (WY) 1989 1989 > SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNU'iL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN- DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 6.9 6.7 6.7 6.9 7.2 6.6 7.0 6.9 7.1 7.0 6.8 7.2 7.2 6.9 6.8 6.6 6.9 6.8 6.5 6.5 6.5 6.2 6.2 5.8 4.8 3.6 3.6 3.8 4.2 4.2 4.0 190.1 6.13 7.2 3.6 377 1.22 1.41 DATA 7.89 15.8 1982 1.69 1989 FOR 3.8 3.5 3.4 3.7 3.7 3.8 3.7 3.4 3.4 3.4 2.1 2.5 1.7 1.6 1.8 2.0 2.1 2.1 2.4 2.2 2.1 2.1 2.0 1.6 1.6 2.0 2.2 1.8 1.5 1.5 1.5 76.2 2.46 3.8 1.5 151 .49 .56 FOR WATER 2.66 4.06 1982 1.47 1989 1.6 1.7 1.7 1.6 1.7 2.1 3.2 4.1 3.6 2.6 2.2 2.4 2.8 8.4 2.1 1.7 1.4 1.5 1.5 1.3 1.5 1.7 1.6 1.6 1.8 2.2 1.6 1.6 ___ ___ 62.8 2.24 8.4 1.3 125 .45 .46 YEARS 1981 2.36 2.92 1982 1.92 1989 1.9 1.8 1.8 2.0 1.9 1.6 1.8 1.7 3.5 2.9 1.9 3.2 8.4 13 3.3 2.3 1.9 1.5 1.5 1.5 1.5 1.4 1.6 1.5 1.4 1.5 1.6 1.5 1.6 1.6 1.6 76.2 2.46 13 1.4 151 .49 .56 - 1990 1.85 2.46 1990 1.47 1982 1989 CALENDAR YEAR 4162. 11. 420 1. 1. 8260 2. 30. 22 2. 1. 80 4 Sep 18 0 Apr 24 1 Apr 19 27 79 0 2 1.6 1.6 1.8 1.7 1.7 1.7 1.8 2.0 2.3 2.2 1.9 2.6 2.9 2.5 2.3 2.3 3.1 5.2 4.1 12 2.7 2.1 1.7 1.5 1.5 1.6 1.3 1.0 1.0 .86 72.56 2.42 12 .86 144 .48 .54 , BY WATER 3.21 7.78 1981 1.32 1982 .97 1.1 1.1 .89 .89 .94 1.6 1.9 2.1 4.4 3.4 2.5 2.5 2.3 2.1 2.0 2.2 2.3 1.9 1.6 1.8 1.5 1.4 1.6 1.6 1.7 2.0 1.9 1.8 1.6 2.2 57.79 1.86 4.4 .89 115 .37 .43 YEAR (WY) 10.2 31.8 1981 1.42 1989 2.6 2.4 2.1 2.4 3.5 2.7 2.6 2.2 1.4 1.9 2.2 2.3 2.2 1.4 6.3 2.0 1.6 2.1 2.0 2.2 2.0 2.1 2.3 5.4 3.3 2.4 el. 9 el. 7 el. 7 el. 6 72.5 2.42 6.3 1.4 144 .48 .54 3.96 10.4 1981 1.16 1982 FOR 1990 WATER YEAR 3263.05 8.94 253 .86 .96 1800 10.77 6470 1.78 24.13 13 2.2 1.5 Oct 3 Apr 30 Apr 30 Sep 13 Sep 13 el. 6 el. 5 el. 4 el. 5 el. 4 el. 5 el. 5 el. 4 el. 4 1.9 2.3 1.9 2.2 2.6 2.2 1.9 2.9 1.3 1.8 2.2 1.7 1.2 1.3 2.0 2.0 el. 8 el. 8 el. 6 el. 4 el. 2 el. 2 53.6 1.73 2.9 1.2 106 .34 .40 2.78 5.68 1981 1.45 1982 WATER 7 8 6 420 5180 1 19 13 2 1 1.6 1.7 1.8 1.7 1.6 1.7 1.6 1.7 1.6 1.8 2.1 1.7 40 6.9 1.7 1.8 1.7 1.5 1.4 1.6 1.9 1.9 1.9 el. 5 el. 3 el. 2 el. 5 1.8 36 e2.0 el. 7 129.9 4.19 40 1.2 258 .83 .96 5.05 12.3 1989 1.03 1982 YEARS 1981 .15 .94 .17 Sep .74 Sep .80 Apr .42 .31 .2 .1 el. 4 el. 3 el. 7 el. 5 1.6 42 15 2.8 7.6 7.2 3.7 4.0 169 31 15 4.5 e2.4 e2.1 el. 9 el. 7 el. 5 el. 3 1.7 56 24 7.1 3.5 3.2 2.5 8.1 426.3 14.2 169 1.3 846 2.83 3.15 18.5 39.6 1989 9.83 1981 - 1990 1990 1982 18 1989 4 1982 25 1982 RIO GRANDB DB MANATI BASIN 50030460 RIO OROCOVIS AT OROCOVIS, PR--Continued DISCHARGE, CUBIC PBBT PER SECOND, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES 87 DAY OCT NOV DEC JAN PBB MAR APR MAY JUN JUL AOQ SEP 1 3.7 12 2 2.8 11 3 3.0 11 4 3.5 10 5 5.0 10 6 3.7 9.7 7 3.1 8.8 8 2.9 8.0 9 3.1 8.0 10 4.8 7.1 11 4.0 6.9 12 3.3 7.0 13 10 6.4 14 82 6.3 15 110 6.2 16 130 6.5 17 88 6.1 18 76 5.9 19 68 5.8 20 24 106 21 209 38 22 54 47 23 30 26 24 34 16 25 92 13 26 111 12 27 53 12 28 38 11 29 25 10 30 19 11 31 15 TOTAL 1310.9 454.7 MEAN 42.3 15.2 MAX 209 106 MIN 2.8 5.8 AC-PT 2600 902 CPSM 8.41 3.01 IN. 9.69 3.36 e Estimated 10 10 27 15 11 9.3 8.8 8.1 8.8 8.3 8.0 7.9 7.4 7.3 7.8 7.1 6.1 6.1 5.7 6.4 5.1 6.1 6.5 6.1 4.7 4.8 4.5 4.7 4.2 6.0 26 264.8 8.54 27 4.2 525 1.70 1.96 STATISTICS OP MONTHLY MEAN DATA MEAN 31.6 9.08 MAX 58.0 15.2 (WY) 1990 1991 MIN 7.40 3.38 (WY) 1989 1989 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK PLOW INSTANTANEOUS PEAK STAGE ANNUAL RUNOFF (AC-PT) ANNUAL RUNOFF (CPSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 8.05 15.8 1982 1.69 1989 POR 9.5 6.2 4.8 4.1 3.8 4.4 4.2 4.5 3.8 3.9 3.1 3.2 3.2 2.5 2.5 2.8 2.5 2.0 1.9 2.0 1.7 1.8 2.2 1.7 1.8 1.6 1.7 1.5 1.5 1.6 1.8 93.8 3.03 9.5 1.5 186 .60 .69 1.7 1.5 1.4 1.3 2.1 4.3 2.4 1.6 1.3 3.7 3.1 6.6 5.7 2.9 2.3 2.7 1.8 2.5 5.1 2.3 2.5 1.7 1.4 1.4 1.4 1.3 1.3 1.2 _._ __. 68.5 2.45 6.6 1.2 136 .49 .51 POR WATER YEARS 1981 2.75 4.06 1982 1.47 1989 2.38 2.92 1982 1.92 1989 1.1 1.1 1.1 .98 1.2 1.2 1.3 1.2 1.3 1.5 1.6 1.5 1.5 1.4 1.2 1.2 1.1 1.4 1.3 1.3 1.4 3.8 2.4 1.6 1.4 19 7.6 3.7 2.7 2.2 1.8 73.08 2.36 19 .98 145 .47 .54 - 1991 1.97 2.46 1990 1.47 1982 1990 CALENDAR YEAR 3058.25 8.38 209 .86 .96 6070 1.67 22.62 13 2.2 1.5 Oct 21 Apr 30 Apr 30 1.7 1.7 1.9 2.1 1.9 1.9 2.0 2.2 1.8 1.9 1.8 2.2 3.0 2.3 2.5 2.2 1.8 2.2 2.3 2.0 1.4 1.5 1.6 1.5 1.4 1.6 1.6 1.6 1.8 12 67.4 2.25 12 1.4 134 .45 .50 55 9.2 4.5 3.6 3.3 2.6 8.2 6.2 2.7 4.6 4.6 41 104 42 23 11 7.2 6.6 5.0 3.5 3.2 3.2 3.5 3.4 2.9 2.9 3.5 4.3 3.5 3.6 3.7 385.5 12.4 104 2.6 765 2.47 2.85 2.7 2.3 2.3 2.3 2.7 2.7 1.5 1.2 .87 1.3 .98 .89 1.0 .70 .95 .92 .84 .87 .95 1.6 2.8 2.0 1.0 1.0 .95 .93 1.0 .98 1.0 .96 42.19 1.41 2.8 .70 84 .28 .31 .94 1.3 1.3 e.90 e.90 .94 1.2 30 12 2.0 .95 el.O el.O el.l el. 3 139 24 8.7 4.1 2.5 2.0 1.7 1.8 1.8 3.2 3.2 1.5 5.3 2.1 1.5 1.3 260.53 8.40 139 .90 517 1.67 1.93 2.0 5.7 10 11 5.0 el. 4 1.6 3.1 3.4 2.8 el. 3 1.1 1.4 20 9.2 2.7 10 6.6 2.0 2.8 2.7 12 17 4.9 3.2 1.5 34 22 7.0 3.6 2.8 213.8 6.90 34 1.1 424 1.37 1.58 2.5 2.7 1.6 1.4 el. 4 el. 3 29 19 9.6 6.2 el. 9 el. 8 el. 8 el. 6 el. 5 el. 5 3.7 2.4 1.1 1.9 3.0 1.8 2.3 1.8 el. 3 el. 4 13 9.9 4.0 3.5 135.9 4.53 29 1.1 270 .90 1.01 , BY WATER YEAR (WY) 3.02 7.78 1981 1.32 1982 POR 1991 3371 9 209 803 8 6690 1 24 19 2 1 10.7 31.8 1981 1.42 1989 WATER YEAR .10 .24 Oct 21 .70 Jun 14 .88 Jun 12 Nov 20 .81 Nov 20 .84 .93 .9 .2 3.45 10.4 1981 1.16 1982 3.90 8.40 1991 1.45 1982 WATER 7 9 6 420 5560 1 20 13 2 1 5.42 12.3 1989 1.03 1982 YEARS 1981 .67 .24 .17 Sep . 7 0 Jun .80 Apr .52 .72 .3 .1 15.7 39.6 1989 4.53 1991 - 1991 1991 1982 18 1989 14 1991 25 1982 88 RIO GRANDB DE MANATI BASIN 50030460 RIO OROCOVIS AT OROCOVIS, PR—Continued DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN MAR APR MAY JUN JUIi AUG SEP 1 2.2 7.8 2 2.2 6.9 3 1.9 3.7 4 1.6 1.8 5 1.7 3.1 6 1.7 3.3 7 20 3.6 8 9.7 3.3 9 4.3 2.4 10 3.9 2.2 11 3.1 1.7 12 3.4 el. 3 13 3.1 el. 2 14 2.5 el. 2 15 1.7 1.2 16 1.7 1.3 17 1.3 .99 18 1.2 2.0 19 2.3 2.6 20 6.9 2.6 21 5.9 2.0 22 3.0 el. 3 23 5.3 el. 2 24 1.8 el.l 25 1.8 .93 26 1.3 .86 27 el. 3 1.0 28 el. 2 1.1 29 8.4 1.1 30 19 e.96 31 17 TOTAL 142.4 65.74 MEAN 4.59 2.19 MAX 20 7.8 MIN 1.2 .86 AC-FT 282 130 CFSM .91 .44 IN. 1.05 .49 e Estimated el.O 1.3 1.2 1.4 1.3 1.3 1.3 1.3 1.5 1.3 1.2 1.5 1.2 1.4 1.8 1.0 .98 1.1 1.1 9.1 13 1.8 1.4 1.2 1.1 1.3 .97 .94 .89 1.1 1.2 58.18 1.88 13 .89 115 .37 .43 STATISTICS OF MONTHLY MEAN DATA MEAN 26.2 7.70 MAX 58.0 15.2 (WY) 1990 1991 MIN 4.59 2.19 (WY) 1992 1992 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 6.82 15.8 1982 1.69 1989 FOR 1.0 .97 .92 .98 415 358 48 41 32 25 19 15 18 14 11 8.7 7.6 5.5 5.0 3.6 3.0 2.7 3.9 3.7 2.9 2.9 2.7 3.3 2.6 2.5 2.8 1063.27 34.3 415 .92 2110 6.82 7.86 1.9 1.5 1.7 1.8 1.9 12 14 12 5.1 2.9 2.1 2.0 2.3 1.8 1.7 1.6 2.5 1.5 1.4 1.5 1.2 1.2 1.3 1.4 1.7 1.6 1.5 1.5 1.5 ___ --- 86.1 2.97 14 1.2 171 .59 .64 FOR WATER YEARS 1981 9.06 34.3 1992 1.47 1989 2.50 2.97 1992 1.92 1989 1.3 1.2 1.7 1.4 1.2 1.2 1.1 1.4 1.5 1.9 1.2 1.0 .90 .92 1.1 1.0 2.7 2.1 1.2 .91 .92 1.1 1.2 el.O el. 6 el. 8 6.8 7.7 6.6 3.1 1.9 60.65 1.96 7.7 .90 120 .39 .45 - 1992 1.97 2.46 1990 1.47 1982 1991 CALENDAR YEAR 1607.02 4.40 139 .70 .88 3190 .88 11.88 8.3 1.9 1.0 Jul 16 Jun 14 Jun 12 2.4 4.5 2.2 1.5 1.6 1.5 2.4 1.7 71 26 13 13 11 8.4 9.6 32 24 14 86 40 15 7.7 5.3 4.0 2.6 2.5 2.0 1.8 1.8 2.9 411.4 13.7 86 1.5 816 2.73 3.04 3.0 7.2 3.2 2.3 1.5 7.4 3.4 1.8 1.5 1.5 1.4 2.2 1.2 5.6 8.5 3.1 7.2 5.0 4.3 35 17 7.4 213 131 56 160 37 21 16 44 99 907.7 29.3 213 1.2 1800 5.82 6.71 158 51 29 21 17 15 13 12 11 12 10 9.6 12 8.2 7.3 7.4 6.6 6.0 5.6 5.6 6.3 4.7 4.3 3.9 3.6 3.3 3.2 3.1 2.7 3.0 --- 455.4 15.2 158 2.7 903 3.02 3.37 2.5 11 4.5 3.1 2.3 3.5 2.8 4.1 2.4 3.8 2.6 1.9 1.6 1.8 1.9 2.6 1.9 2.1 1.6 1.8 1.4 1.5 1.4 1.2 1.2 2.2 1.9 1.0 1.0 .85 1.1 74.55 2.40 11 .85 148 .48 .55 1.5 1.9 .93 1.4 3.0 4.5 1.3 1.3 1.3 1.4 1.6 1.7 el. 4 el. 3 el. 3 1.5 1.4 1.4 1.3 1.2 el.O e.96 e.93 1.0 1.1 1.2 1.2 1.3 1.5 1.5 1.7 46.02 1.48 4.5 .93 91 .30 .34 2.1 2.6 2.9 2.8 2.5 2.9 2.2 5.7 2.5 1.3 e.90 e.86 1.5 1.2 .86 .83 e.88 el. 2 el. 6 el. 8 e2.1 el. 4 e.86 e.94 el. 7 e.88 e.88 e.88 e.80 e2.0 --- 51.57 1.72 5.7 .80 102 .34 .38 , BY WATER YEAR (WY) 4.80 13.7 1992 1.32 1982 FOR 1992 3422. 9. 415 . 2320 11. 6790 1. 25. 14 1. 1. 13.8 31.8 1981 1.42 1989 WATER YEAR 98 35 Jan 5 80 Sep 29 99 Sep 23 Jan 5 53 Jan 5 86 32 9 0 5.40 15.2 1992 1.16 1982 3.65 8.40 1991 1.45 1982 WATER 8 9 6 420 2320 11 5800 1 21 13 2 1 4.76 12.3 1989 1.03 1982 YEARS 1981 .01 .35 .17 .70 .80 .53 .59 .63 .2 .1 Sep Jun Apr Jan Jan 13.3 39.6 1989 1.72 1992 - 1992 1992 1982 18 1989 14 1991 25 1982 5 1992 5 1992 89 RIO GRANDEE DB MANATI BASIN 50030700 RIO OROCOVIS NEAR OROCOVIS, PR WATER-QUALITY RECORDS LOCATION.—Lat 18°14'20", long 66°22'58", at flat low bridge about 300 ft (91 m) northwest of Highway 568, 1.0 mi (1.6 km) north of Orocovis plaza. DRAINAGE AREA.--10.1 mi 1 (26.2 km 1 ). PERIOD OF RECORD.--Water year 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE DIS- CHARGE, INST. CUBIC FEET TIME PER SPE- CIFIC CON- DUCT- ANCE PH WATER WHOLE FIELD TBMPBR- (STAND- ATURB ARD WATER TUR- OXYGEN, BID- DIS- ITY SOLVED OXYGEN, OXYGEN DIS- DEMAND, SOLVED CHEM- (PBR- ICAL CENT (HIGH SATUR- LEVEL) COLI- STRBP- FORM, TOCOCCI FECAL, FECAL, 0.7 UM-MF (COLS./ KF AGAR (COLS. PER SECOND (US/CM) UNITS) (DBG C) (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) OCT 1991 10... DEC 16... FEB 1992 26. .. MAY 29... JUN 30... AUG 11... 1300 1100 1145 1010 0915 0915 6.4 4.5 8.3 24 15 7.9 316 229 284 235 275 312 8.2 8.3 8.1 7.4 7.8 7.8 24.0 20.5 22.5 22.5 24.0 24.5 10 1.7 3.0 2.7 2.0 2.2 7.9 8.3 8.2 8.0 8.4 8.0 84 99 98 92 102 93 15 27 16 <10 <10 18 K7200 K140 230 K7800 K1900 24000 900 K200 220 870 K550 360 DATE OCT 1991 10... DEC 16. .. FEB 1992 26... MAY 29... JUN 30... AUG 11. .. HARD- NESS TOTAL (MG/L AS HARD- NESS NONCARB CALCIUM WH WAT TOT FLD DIS- SOLVED MG/L AS (MG/L CACO3) CACO3 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS NA) 130 5 33 12 13 90 0 22 8.6 12 130 13 34 12 14 SODIUM AD- SORP- TION RATIO POTAS- SIUM, DIS- SOLVED AS K) 0.5 1.7 0.5 2.0 0.5 1.9 ALKA- LINITY WAT WH TOT FBT SULFIDB FIELD CAC03 120 140 110 82 120 110 TOTAL (MG/L MG/L AS (MG/L SULFATB DIS- SOLVED (MG/L CHLO- RIDE, DIS- SOLVED (MG/L AS S) AS S04) AS CL) <0.5 16 20 <0.5 7.5 14 8.3 17 SOLIDS, RESIDUE DATE OCT 1991 10... DEC 16... FBB 1992 26... MAY 29.. . JUN 30.. . AUG 11.. . FLUO- RIDB, DIS- SOLVED (MG/L AS F) <0.10 -- -- 0.10 -- 0.10 SILICA, DIS- SOLVED (MG/L AS SI 02) 32 -- -- 30 — 32 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 200 -- -- 145 -- 198 SOLIDS, DIS- SOLVED (TONS PER DAY) 3.44 -- -- 9.26 — 4.22 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 11 1 1 17 <1 <1 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.680 0.350 0.860 0.830 0.600 0.640 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.010 0.010 0.020 0.020 0.010 0.010 NITRO- GEN, N02+NO3 TOTAL (MG/L AS N) 0.690 0.360 0.880 0.850 0.610 0.650 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.020 0.030 0.050 0.060 0.050 0.030 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) -- 5.6 — -- 0.35 -- K = non-ideal count RIO GRANDB DE MANATI BASIN 50030700 RIO OROCOVIS NEAR OROCOVIS, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 10.. . DEC 16... FEB 1992 26... MAY 29.. . OUN 30... AUG 11... DATE OCT 1991 10... DEC 16.. . FEB 1992 26... MAY 29.. . JUN 30... AUG 11.. . NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) <0.20 5.6 <0.20 <0.20 0.40 <0.20 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) -- 6.0 -- — 1.0 -- LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N03) -- 26 -- -- 4.5 -- MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.070 0.060 0.220 0.090 0.120 0.150 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) ARSENIC TOTAL (UG/L AS AS) <1 -- -- <1 -- -- SELE- NIUM, TOTAL (UG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 — — <100 — -- SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) 50 -- -- 10 -- -- ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 — — <1 — -- CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) <1 -- -- <1 -- -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CD) 10 — — <10 — -- MBTHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 1100 140 40 20 <0.10 <0.10 <0.010 20 <0.010 21 0.02 0.06 91 RIO GRANDB DB MANATI BASIN 50031200 RIO GRANDB DB MANATI NEAR MOROVIS, PR LOCATION.--Lat 18«17'45-, long 66°24'47-, Hydrologic Unit 21010001, on right bank , 0.1 mi (0.2 km) down*trearn from Quebrada Percha», 0.8 »i (1/3 km) up»tream from Rio Sana Muerto, and 2.2 mi (3.5 km) »outh of Morovi». DRAINAGE AREA.--55.2 mi' (143.0 km'). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—January 1965 to current year. GAGB.--Water-»tage recorder and concrete control. Elevation of gage i» 440 ft (134 m), from topographic map. Feb. 2, 1966 to Apr. 27, 1967, »taff gage read twice daily. REMARKS.--Record* fair except tho»e for estimated daily di•charge*, which are poor. Public water-»upply pumpage, about 300 ft (91 m) above the station, influence* low-flow di(charge*. Gage-height and precipitation satellite telemetry at station. DAY DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES OCT NOV DEC JAN PBB MAR APR MAY JUN JUL ADG SBP 1 24 211 2 24 190 3 22 114 4 19 75 5 20 57 6 21 53 7 34 58 8 92 60 9 48 49 10 28 41 11 23 35 12 23 32 13 21 32 14 20 32 15 19 34 16 18 31 17 17 30 18 17 29 19 49 28 20 44 28 21 26 28 22 25 33 23 39 32 24 25 52 25 23 38 26 30 31 27 20 28 28 19 33 29 49 29 30 224 26 31 216 TOTAL 1279 1549 MEAN 41.3 51.6 MAX 224 211 MIN 17 26 AC-FT 2540 3070 CPSM .75 .94 IN. .86 1.04 e B»timated STATISTICS OP MONTHLY MEAN MEAN 168 158 MAX 1037 491 (WY) 1971 1971 MIN 24.0 28.3 (WY) 1978 1974 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW PLOW ANNUAL RUNOFF (AC- FT) ANNUAL RUNOFF (CPSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 26 25 26 29 30 28 26 25 27 34 29 27 25 25 25 25 25 24 24 43 176 69 46 34 30 29 33 33 31 27 27 1083 34.9 176 24 2150 .63 .73 DATA 118 522 1966 27.9 1984 FOR 27 26 25 24 2480 1530 246 147 116 117 e86 e82 e88 e84 e70 e70 e76 e62 e55 eSl e47 e46 e44 46 44 44 41 40 41 38 38 5931 191 2480 24 11760 3.47 4.00 FOR WATER 83.9 191 1992 24.7 1984 37 36 35 37 35 37 74 65 44 39 38 95 47 37 35 33 30 31 31 32 32 32 e33 e32 e32 e33 e30 e33 e36 ___ --- 1141 39.3 95 30 2260 .71 .77 YEARS 1965 66.5 179 1969 23.4 1984 e33 e30 e30 e30 e29 e28 e29 e30 e33 e35 e28 e27 e26 e25 e25 e25 31 49 39 32 27 28 27 24 23 22 128 62 71 42 39 1107 35.7 128 22 2200 .65 .75 - 1992 70.4 226 1972 12.7 1984 1991 CALENDAR YEAR 19164 52. 605 15 19 38010 12. 98 5 Jul 16 Sep 6 Aug 31 95 91 35 143 95 62 42 38 69 73 293 220 101 70 58 48 57 180 190 129 e580 e450 e200 96 73 62 54 50 46 43 64 141 --- 3762 125 580 35 7460 2.27 2.54 223 289 135 92 70 187 120 76 62 55 49 47 48 46 66 54 100 156 233 305 248 130 457 599 261 474 246 165 135 144 231 5503 178 599 46 10920 3.22 3.71 283 191 138 122 113 99 91 92 106 145 124 92 91 87 71 68 66 62 59 58 56 55 52 50 48 46 45 45 42 41 --- 2638 87.9 283 41 5230 1.59 1.78 41 41 67 43 41 39 38 54 56 42 39 42 39 54 41 48 41 40 35 35 33 32 34 43 37 34 33 32 32 31 30 1247 40.2 67 30 2470 .73 .84 35 32 33 63 69 119 54 42 37 36 34 35 32 30 46 34 29 28 26 119 97 39 29 27 35 27 26 24 23 23 25 1308 42.2 119 23 2590 .76 .88 24 21 23 26 42 45 31 27 63 29 22 21 20 19 19 19 21 22 29 69 31 24 24 23 20 20 20 17 17 56 --- 844 28.1 69 17 1670 .51 .57 , BY WATER YEAR (WY) 114 412 1969 10.6 1984 FOR 1992 27392 74 2480 17 19 19000 11 16 54330 1 18 139 170 915 1985 23.6 1977 WATER YEAR .8 Jan 5 Oct 17 Oct 12 Jan 5 . 27 Jan 5 Sep 28 .36 .46 65.2 173 1987 16.9 1977 48.4 157 1979 18.5 1977 WATER 102 248 40 17100 5 6 48000 17 4 73880 1 25 179 59.0 435 1979 9.70 1984 YEARS 1965 - .3 May 18 .7 Aug 20 .8 Aug 18 May 18 .89 May 18 .4 Apr 15 .85 .10 93.2 386 1979 25.0 1977 1992 1971 1974 1985 1984 1984 1985 1985 1984 92 PERIOD OF RECORD.-- RIO QRANDB OB MANATI BASIN 50031200 RIO GRANDB OB MANATI NEAR MOROVIS, PR--Continued WATER-QUALITY RECORDS Water years 1968 to current year. WATER-QUALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 09... DEC 12. .. FBB 1992 26... APR 21. .. JUN 30. .. AUG 11... TIME 1115 1415 0945 0945 1105 1125 DIS- CHARGE, INST. CUBIC FBBT PER SECOND 43 25 34 140 40 33 SPE- CIFIC CON- DUCT- ANCE (US/CM) 222 298 281 199 250 230 PH WATER HHOLB FIELD (STAND- ARD UNITS) 7.8 8.5 8.0 7.0 8.3 8.2 TEMPER- ATURE WATER (DBG C) 24.5 24. S 23.0 24.0 24.0 27.0 TUR- BID- ITY (NTU) 110 S.5 1.3 67 l.S 3.1 OXYGEN, DIS- SOLVED (MG/L) 8.0 8.3 8.3 8.7 7.5 7.0 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 93 98 100 104 99 86 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 31 IS 14 17 <10 17 COLI- FORM, FECAL, 0.7 UM-MF (COLS./ 100 ML) 23000 K10 130 2800 110 2700 STREP- TOCOCCI FECAL, KF AGAR (COLS. PER 100 ML) 9500 90 100 2000 450 60 DATE OCT 1991 09. .. DEC 12... FBB 1992 26... APR 21... JUN 30. .. AOG 11. .. HARD- NESS TOTAL (MG/L AS HARD- NESS NONCARB WH WAT TOT FLD MG/L AS CALCIUM DIS- SOLVED (MG/L MAGNE- SIUM, DIS- SOLVED (MG/L SODIUM, DIS- SOLVED (MG/L SODIUM AD- SORP- TION RATIO CAC03) CACO3 83 76 120 AS CA) AS MG) AS NA) 20 18 8.1 11 7.6 10 ALKA- POTAS- LINITY SIUM, HAT HH DIS- TOT PET SULFIDB SOLVED FIELD TOTAL (MG/L MG/L AS (MG/L 29 12 14 AS K) 0.5 2.4 O.S 3.6 0.6 2.1 CACO3 79 110 110 57 120 120 CHLO- SOLFATB RIDE, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS S) AS SO4) AS CL) <O.S 7.7 14 <0.5 11 16 7.4 17 SOLIDS, RESIDUE DATE OCT 1991 09... DEC 12.. . FEB 1992 26... APR 21.. . JUN 30.. . AUG 11... FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.20 -- -- 0.10 -- 0.20 SILICA, DIS- SOLVED (MG/L AS SI02) 21 -- __ 22 -- 25 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 132 -- __ 122 -- 175 SOLIDS, DIS- SOLVED (TONS PER DAY) 15.1 -- __ 46.1 — 15.6 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 33 17 1 64 <1 <1 NITRO- NITRO- NITRO- NITRO- NITRO- GEN, GEN, GEN, GEN, GEN, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC TOTAL TOTAL TOTAL TOTAL TOTAL (MG/L (MG/L (MG/L (MG/L (MG/L AS N) AS N) AS N) AS N) AS N) O.S60 1.25 0.070 <0.010 <0.010 0.050 <0.010 <0.010 0.630 0.360 0.300 1.30 0.170 0.270 0.080 0.020 0.020 0.070 0.080 0.030 0.42 — — O.S3 0.72 — K = non-ideal count RIO GRANDE DE MANATI BASIN S0031200 RIO GRANDE DE MANATI NEAR MOROVIS, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 93 DATE OCT 1991 09... DEC 12... FBB 1992 26.. . APR 21... JUN 30.. . AUG 11.. . DATE OCT 1991 09.. . DEC 12. .. FBB 1992 26.. . APR 21.. . JUN 30... AUG 11.. . NITRO- GEN, AM- MONIA * ORGANIC TOTAL (MG/L AS N) 0.50 <0.20 <0.20 0.60 0.80 <0.20 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) 1.1 -- -- 1.9 0.97 -- LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N03) 5.0 -- -- 8.4 4.3 -- MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.160 0.070 0.060 0.130 0.040 0.040 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) ARSENIC TOTAL (UG/L AS AS) <1 -- -- <1 -- -- SELE- NIUM, TOTAL (UG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 - -- <100 -- -- SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (DG/L AS B) 30 -- -- 20 -- -- ZINC, TOTAL RECOV- ERABLE (DG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (DG/L AS CD) <1 — — 1 -- -- CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) 8 -- -- 12 -- -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) 20 — — 20 — -- METHY- LENB BLUE ACTIVE SUB- STANCE (MG/L) 7100 5600 140 110 <0.10 <0.10 20 <0.010 10 <0.010 0.01 0.02 94 RIO GRANDB DB MANATI BASIN 50032290 LAGO EL GUINBO AT DAMSITB, PR LOCATION.--Lat 18°09'41", long 66°51'48", Hydrologic Unit 21010001, at damsite on Rio Toro Negro, 3.0 mi (4.8 km) northwest from Villalba plaza and 1.9 mi (3.1 km) northeast of Cerro Maravillas. The reservoir itself fixes the territorial limits between the Municipality of Ciales and Orocovis. DRAINAGE AREA.--1.64 mi> (4.25 km*). PERIOD OF RECORD.--May 1988 to current year. ELEVATION RECORDS GAGB.—Water-stage recorder. Datum of gage is mean sea level. REMARKS.--Lago Guineo was completed in 1931. It provides a maximum storage of approximately 2,180 ac-ft (2.688 hm3 ) for power and irrigation. Waters are discharged through an outlet power tunnel into the Rio Toro Negro and coveyed to the head water works of Toro Negro Hydroelectric Plant No.2, for energy generation at Toro Negro Hydroelectric plant No.l, and are discharged into the Guayabal Reservoir to be later used for irrigation at South Coast Irrigation System. The dam is rockfill with a vertical concrete corewall, rock toes, and riprap facing of upstream slope, with a total length of 565 ft (172 m), a maximum structural height of 125 ft (38 m) to top of corewall. At a maximum reservoir water surface elevation the uncontrolled morning-glory tunnel spillway crest has an elevation of 2,966 ft (904 m) above mean sea level and a design capacity of 7,000 ftVs. The dam is owned by Puerto Rico Electric Power Authority. Gage-height and precipitation satellite telemetry at station. EXTREMES OBSERVED FOR PERIOD OF RECORD.—Maximum elevation 2,961.70 ft (902.73 m), Oct. 21, 1990; minimun elevation, 2,919.79 ft (899.95 m), May 27, 1988. EXTREMES OBSERVED FOR CURRENT YEAR.--Maximum elevation, 2,961.11 ft (902.55 m), Jan. 6; minimun elevation, 2,941.60 ft (896.60 m), Jan. 3. Capacity Table (based on data from Puerto Rico Electric Power Authority) Elevation, in feet 2,872 2,919 2,925 Contents, in acre-feet 0 361 491 Elevation, in feet 2,943 2,950 2,961 Contents, in acre-feet 1,029 1,308 1,852 DAY ELEVATION (FEET NGVD), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY OBSERVATION AT 24:00 VALUES OCT NOV DEC JAN PBB MAR APR MAY JUN JUL AUG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN MAX MIN 2949.48 2949.20 2948.86 2948.46 2948.52 2948.57 2948.86 2948.72 2948.66 2948.32 2948.06 2947.49 2946.92 2946.76 2946.44 2946.52 2946.60 2946.72 2946.80 2946.88 2947.00 2947.04 2946.74 2946.46 2946.45 2946.52 2946.65 2946.56 2947.33 2947.23 2947.25 2947.49 2949.48 2946.44 2947.21 2947.33 2947.41 2947.31 2947.21 2947.31 2947.23 2947.33 2947.54 2947.65 2947.73 2947.41 2946.90 2946.44 2946.49 2946.55 2946.61 2946.10 2946.16 2946.21 2946.12 2945.88 2945.92 2945.99 2945.86 2945.74 2945.84 2945.93 2945.97 2946.01 --- 2946.65 2947.73 2945.74 2946.06 2945.67 2945.27 2945.04 2944.80 2944.48 2944.52 2944.56 2944.21 2944.23 2944.29 2943.91 2943.96 2944.00 2944.02 2944.04 2944.11 2944.13 2944.17 2944.34 2944.43 2944.47 2944.50 2944.54 2944.56 2944.60 2944.40 2943.34 2943.36 2942.96 2942.65 2944.31 2946.06 2942.65 2942.88 2942.50 2942.06 2942.10 2954.57 2961.03 2960.40 2959.90 2959.38 2958.83 2958.34 A A A A A A A A A A A A 2955.00 2955.19 2955.29 2954.85 2954.47 2953.87 2953.17 2952.83 ___ ___ 2952.29 2952.39 2952.19 2952.06 2951.93 2953.03 2953.29 2953.04 2953.21 2953.03 2953.15 2952.59 2952.26 2952.08 2951.87 2951.96 2952.05 2951.83 2951.43 2951.23 2951.02 2950.38 2950.46 2949.92 2950.00 2950.11 2950.20 2950.30 2949.52 ___ --- 2951.68 2953.29 2949.52 2949.59 2949.52 2949.58 2949.66 2949.72 2949.79 2949.86 2949.94 2950.09 2950.17 2950.23 2950.14 2949.90 2949.94 2950.00 2949.84 2949.94 2949.98 2950.03 2950.12 2950.19 2950.25 2950.31 2950.10 2950.15 2950.21 2950.16 2950.25 2950.61 2950.44 2952.01 2950.09 2952.01 2949.52 2952.14 2952.88 2953.07 2953.17 2953.25 2952.97 2952.71 2952.77 2953.12 2952.99 2952.55 2952.68 2952.43 2952.15 2951.99 2952.23 2952.43 2952.57 2953.58 2954.88 2954.64 2954.02 2953.54 2953.24 2953.38 2953.52 2953.00 2952.40 2952.38 2952.40 --- 2952.97 2954.88 2951.99 2952.32 2952.44 2952.54 2952.18 2951.92 2951.94 2951.81 2951.74 2951.83 2951.91 2951.38 2951.58 2951.70 2952.20 2952.12 2952.47 2952.64 2952.34 2952.10 2950.83 2950.57 2950.35 2956.76 2958.06 2959.10 2960.74 2960.43 2960.03 2959.85 2959.74 2960.80 2954.08 2960.80 2950.35 2960.80 2960.20 2960.38 2960.33 2960.17 2959.97 2960.19 2960.41 2960.20 2960.00 2959.86 2959.88 2960.15 2960.37 2959.85 2959.47 2959.27 2959.31 2959.25 2959.58 2959.46 2959.32 2959.08 2959.01 2958.86 2958.66 2958.37 2958.50 2958.40 2958.48 --- 2959.59 2960.80 2958.37 2958.39 A A A A A A A A A A A A A A A A A A A A A A A A A 2954.39 2954.10 2954.21 2954.02 2954.10 ___ ___ 2954.16 2954.24 2953.80 2953.74 2954.21 2954.13 2953.90 2953.99 2954.15 2956.42 2956.34 2956.24 2956.10 2955.98 2955.50 2955.58 2955.42 2955.25 2954.85 2954.65 2954.53 2954.05 2953.61 2953.38 2953.22 2953.06 2952.82 2952.66 2952.14 2952.22 2951.72 2954.26 2956.42 2951.72 2951.52 2951.31 2951.09 2950.77 2950.87 2950.93 2953.49 2953.41 2953.25 2953.09 2952.95 2952.37 2952.43 2952.25 2952.14 2952.02 2951.54 2950.96 2950.48 2950.10 2950.00 2949.86 2950.32 2950.48 2950.66 2950.82 2950.94 2951.28 2951.50 2951.75 --- 2951.49 2953.49 2949.86 A No gage-height record. 95 RIO GRANDS DB MANATI BASIN 50032590 LAGO DB MATRULLAS AT DAMSITB, PR LOGATION.--Lat 18°12'46", long 66°28'50", Hydrologic Unit 21010001, in concrete house at damsite, and 5.8 mi (9.3 km) southwest of Orocovis. DRAINAGE AREA.--4.46 mi 1 (11.55 km1 ). PERIOD OF RECORD.--May 1988 to current year. ELEVATION RECORDS GAGE.--Water-stage recorder. Datum of gage is mean sea level. REMARKS.--Lago Matrullas was completed in 1934. The dam is an earthfill structure about 120 ft ( 37 m) height, a top width of 30 ft (9 m) and a length of 710 ft (216 m), and has a maximum storage capacity of about 4,274 ac-ft (5.220 hm3 ) at top of dam elevation. The Matrullas Dam is owned by the Puerto Rico Electric Power Authority and is part of the Toro Negro Hydroelectric Project; a project developed by the P.R.E.P.A. for the primary purpose of generating electric power. Discharges from the Power Plants are collected by the Jacaguas River which flows into Guayabal Dam, at which dam they are regulated for irrigation of lands served by the Juana Diaz Canal. Gage-height and precipitation satellite telemetry at station. EXTREMES OBSERVED FOR PERIOD OF RECORD.--Maximum elevation 2,413.56 ft (735.65 m), Jan. 6, 1992; mi nil 2,392.81 ft (729.33 m), Sept. 10, 1989. elevation, EXTREMES OBSERVED FOR CURRENT YEAR.--Maximum elevation, 2,413.56 ft (735.65 m), Jan. 6; minimum elevation, 2,408.23 ft (734.03 m), Oct. 19. Capacity Table (based on data from Puerto Rico Electric Power Authority) Elevation, in feet 2,338 2,360 Contents, in acre-feet 2 302 Elevation, in feet 2,399 2,415 Contents, in acre-feet 1,845 2,945 DAY ELEVATION (FEET NGVD), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY OBSERVATION AT 24:00 VAL0BS NOV DEC JAN FEB MAR APR MAY JUN JDL ADG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN MAX MIN 2409.81 2409.60 2409.37 2409.13 2409.15 2409.25 2409.52 2409.80 2409.92 2410.06 2410.03 2409.77 2409.41 2409.11 2408.84 2408.65 2408.47 2408.27 2408.28 2408.39 2408.38 2408.54 2408.53 2408.36 2408.31 2408.45 2408.57 2408.58 2408.84 2409.16 2409.21 2409.02 2410.06 2408.27 2409.26 2409.41 2409.55 2409.53 2409.49 2409.49 2409.50 2409.54 2409.64 2409.75 2409.87 2409.75 2409.45 2409.07 2408.92 2408.99 2409.07 2409.05 2409.13 2409.03 2408.89 2408.65 2408.66 2408.77 2408.69 2408.61 2408.61 2408.70 2408.68 2408.76 --- 2409.15 2409.87 2408.61 2408.84 2408.69 2408.57 2408.51 2408.43 2408.33 2408.39 2408.48 2408.33 2408.32 2408.40 2408.48 2408.55 2408.64 2408.72 2408.80 2408.88 2408.96 2409.03 2409.29 2409.71 2409.87 2409.97 2410.04 2410.13 2410.23 2410.32 2410.41 2410.49 2410.45 2410.41 2409.18 2410.49 2408.32 2410. 2410. 2410. 2409. 2412. 2412. 2412. 2411. 2411. 2411. 2411. 2411. 2411. 2411. 2410. 2410. 2410. 2410. 2410. 2410. 2410. 2410. 2410. 2409. 2409. 2410. 2409. 2409. 2409. 2409. 2409. 2410. 2412. 2409. 46 29 03 81 87 55 04 72 54 38 18 45 40 20 96 92 98 78 58 56 42 27 12 98 88 02 94 78 58 28 06 68 87 06 2408.80 2408.81 2408.85 2408.87 2408.86 2409.40 2409.74 2409.76 2409.93 2409.88 2409.78 2409.60 2409.40 2409.28 2409.24 2409.35 2409.52 2409.49 2409.34 2409.30 2409.28 2409.08 2409.11 2409.14 2409.14 2409.16 2409.19 2409.32 2409.44 ___ --- 2409.31 2409.93 2408.80 2409.58 2409.73 2409.86 2409.90 2409.92 2409.99 2409.97 2410.08 2410.12 2410.18 2410.00 2409.76 2409.56 2409.27 2409.23 2409.06 2409.00 2409.00 2408.98 2408.94 2409.03 2409.18 2409.30 2409.26 2409.16 2409.05 2409.00 2409.18 2409.52 2409.66 2409.77 2409.49 2410.18 2408.94 2409.88 2410.20 2410.64 2410.82 2410.97 2410.86 2410.98 2411.02 2411.24 2411.20 2410.98 2411.06 2410.95 2410.78 2410.74 2411.27 2411.42 2411.43 2411.93 2412.18 2411.56 2411.34 2411.27 2411.30 2411.42 2411.44 2411.38 2411.45 2411.34 2411.34 --- 2411.15 2412.18 2409.88 2411.34 2411.53 2411.52 2411.32 2411.22 2411.26 2411.30 2411.30 2411.42 2411.48 2411.25 2411.58 2411.54 2411.69 2411.64 2411.91 2412.38 2411.80 2411.64 2411.56 2411.50 2411.56 2412.80 2412.48 2412.28 2412.51 2412.12 2411.91 2411.86 2411.81 2412.07 2411.73 2412.80 2411.22 2412.46 2411.96 2411.90 2411.89 2411.90 2411.88 2411.95 2411.95 2411.88 2411.86 2411.88 2411.88 2411.90 2411.89 2411.82 2411.80 2411.81 2411.84 2411.80 2411.82 2411.86 2411.82 2411.78 2411.78 2411.76 2411.75 2411.74 2411.79 2411.78 2411.78 2411.86 2412.46 2411.74 2411.77 2411.80 2411.77 2411.75 2411.79 2411.75 2411.72 2411.78 2411.76 2411.72 A A A 2411.75 2411.74 2411.73 2411.73 2411.76 2411.79 2411.78 2411.74 2411.67 2411.69 2411.67 2411.73 2411.76 2411.77 2411.69 2411.66 2411.64 2411.69 ___ 2411.77 2411.81 2411.70 2411.66 2411.70 2411.73 2411.74 2411.75 2411.76 2411.77 2411.72 2411.70 2411.66 2411.66 2411.57 2411.61 2411.60 2411.54 2411.42 2411.52 2411.62 2411.49 2411.29 2411.14 2411.01 2410.93 2410.87 2410.85 2410.67 2410.66 2410.57 2411.43 2411.81 2410.57 2410.46 2410.38 2410.32 2410.24 2410.30 2410.42 2410.53 2411.24 2411.53 2411.49 2411.44 2411.27 2411.29 2411.24 2411.17 2411.11 2410.99 2410.76 2410.46 2410.19 2410.02 2409.95 2410.01 2410.15 2410.14 2410.03 2410.07 2410.09 2410.09 2410.14 --- 2410.58 2411.53 2409.95 A No gage-height record. 96 RIO ORANDB DB MANATI BASIN 50034000 RIO BAOTA HEAR OROCOVIS, PR LOCATION.--Lat 18°14'10' / long 66°27'18' ( Hydrologic Unit 21010001, on left bank, at bridge on Highway 157 (12.1 km), and 4.2 mi (6.8 km) west of Orocovia. DRAINAGE AREA.--16.7 mi * (43.3 km>). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—February 1959 to April 1966 (annual low-flow measurements only), February to September 1969 (occasional measurements only), October 1969 to September 1982, October 1988 to current year. GAGE.—Water-stage recorder and crest-stage gage. Datum of gage is 772.82 ft (235.556 m) above mean sea level. REMARKS.--Record* fair except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. DAY OCT DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES NOV DEC JAN FEB MAR APR MAY JUN JDL AUG 1 11 43 2 11 32 3 10 19 4 9.9 14 5 10 12 6 9.9 13 7 54 16 8 30 24 9 20 14 10 16 12 11 14 11 12 12 10 13 11 9.9 14 10 9.7 15 9.9 9.7 16 9.8 10 17 9.5 9.4 18 9.2 9.0 19 9.3 8.7 20 10 8.5 21 9.8 8.6 22 13 8.8 23 14 8.6 24 11 8.6 25 10 9.4 26 10 8.6 27 9.8 8.5 28 9.2 8.5 29 35 7.9 30 44 7.6 31 63 TOTAL 515.3 380.0 MEAN 16.6 12.7 MAX 63 43 MIN 9.2 7.6 AC-FT 1020 754 CFSM 1.00 .76 IN. 1.15 .85 e Estimated 7.7 7.9 8.1 8.3 8.2 7.8 7.4 7.4 8.0 8.3 8.3 7.8 7.7 7.9 7.5 7.5 7.7 7.8 7.4 17 28 11 9.3 8.5 8.4 7.7 7.9 7.9 7.7 7.6 7.6 277.3 8.95 28 7.4 550 .54 .62 STATISTICS OF MONTHLY MEAN DATA MEAN 99.3 59.2 MAX 392 205 (WY) 1971 1971 MIN 15.8 8.14 (WY) 1976 1974 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST 'ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 29.8 108 1971 8.95 1992 FOR 7.3 7.2 7.2 7.2 904 922 149 66 43 36 30 30 33 30 25 26 28 22 20 18 17 17 16 17 16 16 15 15 15 15 15 2584.9 83.4 922 7.2 5130 4.99 5.76 FOR WATER 20.9 83.4 1992 6.62 1973 14 14 13 13 13 34 34 32 22 18 16 15 e28 el8 el5 e!4 e!3 e!2 e!2 ell ell ell ell elO 11 9.9 9.9 12 12 ___ --- 458.8 15.8 34 9.9 910 .95 1.02 YEARS 1969 14.1 30.9 1971 6.26 1977 11 9.8 9.9 9.7 9.5 9.3 9.4 10 9.8 13 9.5 8.8 8.6 8.4 8.3 8.1 11 11 9.4 8.6 8.3 9.1 8.3 7.9 11 9.0 15 17 91 37 19 425.7 13.7 91 7.9 844 .82 .95 - 1992 16.3 59.9 1972 5.57 1977 1991 CALENDAR YEAR 6282. 17. 362 6. 7. 12460 1. 13. 26 11 0 2 Jul 16 1 Jul 7 1 Jul 1 03 99 23 35 30 17 13 13 38 23 74 71 29 19 15 13 27 99 89 53 276 195 101 48 33 27 22 20 18 16 16 18 1471 49.0 276 13 2920 2.94 3.28 23 56 32 23 19 23 22 17 15 14 14 37 32 59 94 48 135 94 177 103 68 43 315 e671 e200 e410 e220 ellO e70 e60 e50 3254 105 671 14 6450 6.29 7.25 e!60 e260 ellO e70 e56 eSO e45 e43 e43 e41 eS2 e39 e35 e33 e31 e30 e30 e29 29 28 28 28 26 24 23 23 22 21 20 19 1448 48.3 260 19 2870 2.89 3.23 19 24 20 19 18 17 17 21 19 17 17 16 16 17 15 16 15 15 15 15 14 e!3 e!6 e!5 e!3 e!2 e!2 e!2 ell ell e!4 491 15.8 24 11 974 .95 1.09 15 13 12 11 14 23 14 14 13 17 17 15 14 14 15 13 12 11 11 15 21 12 10 9.3 8.7 8.4 8.5 8.6 8.1 7.9 8.0 393.5 12.7 23 7.9 781 .76 .88 7.7 7.7 7.8 8.4 8.7 9.5 8.9 26 23 11 9.0 8.5 8.1 8.1 7.8 8.0 8.5 8.3 8.1 8.4 8.8 8.2 8.2 10 8.3 7.8 7.5 7.2 9.2 18--- 294.7 9.82 26 7.2 585 .59 .66 , BY WATER YEAR (WY) 27.2 80.2 1980 6.23 1977 FOR 1992 11994 32 922 7 7 5920 15 7 23790 1 26 52 14 49.8 179 1981 7.05 1973 WATER YEAR .2 .8 Jan 6 . 2 Jan 2 .4 Dec 29 Jan 5 . 72 Jan 5 .2 Dec 7 .96 .72 20.4 78.6 1979 4.10 1977 17.1 104 1979 5.22 1974 WATER 35 79 13 3870 3 3 17800 21 2 25950 2 29 66 13 22.7 152 1979 6.76 1976 YEARS 1969 .8 .3 .2 Oct .0 Jul .4 Jul Oct .90 Oct .8 Jul .14 .14 54.3 149 1979 9.82 1992 - 1992 1979 1977 9 1970 23 1977 20 1977 9 1970 9 1970 23 1977 97 RIO GRANDB DB MANATI BASIN 50035000 RIO GRANDB DB MANATI AT CIALBS, PR LOCATION.--Lat 18°19'26", long 66°27'36", Hydrologic Unit 21010001, on left bank, 1.6 mi (2.6 km) upstream from Hwy 145 bridge, 0.8 mi (1.3 km) downstream from Quebrada Saliente, 0.9 mi (1.4 km) upstream from Quebrada Cojo Vales, and 1.2 mi (1.9 km) southeast of Ciales. DRAINAGE ARKA.--128 mi 1 (332 km 1 ), excludes 6.0 mi> (15.5 km1 ), the runoff from which is diverted through Bl Ouineo and de Hatrullas reservoirs. WATER-DISCHARGE RECORDS PERIOD OP RECORD.--September 1946 to September 1953, May 1956 to December 1957 (unpublished, available in files of Caribbean District Office and in the National Water Data Storage and Retrieval System, Washington, D.C.); February 1959 to September 1960 (monthly discharge measurements only); October 1960 to current year. Equivalent record from January 1971 to December 1972 published as 50035200 Rio Grande de Manati at Highway 145 at Ciales at site 1.6 mi (2.6 km) downstream, drainage area 132 mi 1 (342 km*). GAGE.--Water-stage recorder. Elevation of gage is 140 ft (43 m), from topographic map. Prior to Apr. 1, 1962 , staff gage, read twice daily, at site 100 ft (30 m) upstream at same datum. January 1971 to December 1972 at site 1.6 mi (2.6 km) downstream at different datum. REMARKS.--Records fair except those for estimated daily discharges, which are poor, satellite telemetry at station. Gage-height and precipitation EXTREMES OUTSIDE PERIOD OP RECORD.--Approximate gage heights of major floods, pointed out by local residents are as follows: August 1899, 50 ft (15 m), September 1928, 36 ft (11 m), and September 1932, 34 ft (10 m) at site 1.6 mi (2.6 km) upstream. DAY DISCHARGE, CUBIC PBBT PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES NOV DEC JAN PBB MAR APR MAY JUN JUL ADO SEP 1 66 e!300 2 64 e940 3 61 e320 4 55 e210 5 52 e!60 6 52 130 7 59 119 8 272 148 9 129 116 10 78 94 11 74 80 12 64 73 13 56 72 14 52 67 15 50 67 16 47 68 17 45 66 18 43 62 19 106 60 20 116 57 21 70 57 22 56 55 23 85 54 24 60 73 25 63 69 26 59 62 27 54 57 28 47 57 29 206 57 30 ellOO 56 31 e920 TOTAL 4261 4806 MEAN 137 160 MAX 1100 1300 MIN 43 54 AC-PT 8450 9530 CPSM 1.07 1.25 IN. 1.24 1.40 e Estimated STATISTICS OP MONTHLY MEAN MEAN 482 382 MAX 2422 1006 (WY) 1971 1971 MIN 97.8 67.6 (WY) 1987 1974 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK PLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW PLOW ANNUAL RUNOFF (AC-PT) ANNUAL RUNOFF (CPSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 54 54 54 54 54 54 52 52 52 61 55 52 51 50 49 47 47 47 47 66 302 122 80 64 57 52 52 53 59 53 52 1998 64.5 302 47 3960 .50 .58 DATA 276 1296 1966 64.5 1992 FOR 52 51 48 45 5110 e5240 e616 e385 265 235 193 236 204 195 160 153 235 158 132 119 110 105 100 97 97 97 88 83 81 81 81 14852 479 5240 45 29460 3.74 4.32 POR WATER 174 479 1992 64.1 1984 79 76 75 78 79 110 237 178 134 111 100 149 96 88 82 77 72 71 71 69 69 69 67 64 64 65 65 64 62 ___ --- 2621 90.4 237 62 5200 .71 .76 YEARS 1961 138 424 1969 47.9 1984 61 57 56 56 56 56 54 89 98 124 92 68 58 55 54 54 61 100 81 67 58 57 61 55 57 117 324 265 e200 e320 ellO 3021 97.5 324 54 5990 .76 .88 - 1992 151 477 1969 36.5 1984 1991 CALENDAR YEAR 48803 134 2030 43 47 96800 1. 14. 217 81 53 Jul 16 Oct 18 Aug 8 04 18 e!50 e84 e580 e!30 e88 e74 e84 ellO elOOO e2200 e350 e200 e!40 99 90 e!30 e390 e!80 e450 el800 e640 e240 e!60 e!30 e!20 ellO elOO e96 e94 e!70 --- 10189 340 2200 74 20210 2.65 2.96 e!80 61600 e410 e220 e!50 316 198 137 109 104 97 e90 e!90 e!30 e!90 e!60 e250 e660 e500 e!200 e880 e390 e!400 e4500 e2300 e3500 1030 529 373 208 894 22895 739 4500 90 45410 5.77 6.65 1710 965 480 376 328 284 275 272 263 326 273 228 213 204 181 169 149 142 145 141 145 144 131 129 125 118 117 114 109 106 8362 279 1710 106 16590 2.18 2.43 102 102 143 105 99 98 95 122 131 102 95 94 93 122 101 102 99 94 91 91 90 86 83 101 89 77 75 75 70 67 67 2961 95.5 143 67 5870 .75 .86 114 81 78 112 120 216 108 86 79 86 168 93 80 72 96 88 76 69 69 169 248 196 119 108 122 103 138 110 99 93 93 3489 113 248 69 6920 .88 1.01 93 90 88 105 151 155 153 173 237 124 95 85 75 72 72 70 84 92 118 238 105 83 76 107 86 77 73 75 83 106 --- 3241 108 238 70 6430 .84 .94 , BY WATER YEAR (WY) 283 1174 1969 28.5 1984 POR 1992 82696 226 5240 43 48 38100 14 43 164000 1 24 327 96 54 472 2293 1985 71.4 1989 WATER YEAR Jan 6 Oct 18 Dec 13 Jan 6 .41 Jan 6 Oct 17 .77 .03 162 458 1979 40.2 1977 110 438 1979 40.2 1974 WATER 256 520 118 42700 5 22 125000 24 20 185800 2 27 458 118 55 154 1212 1979 33.6 1984 YEARS 1961 - May 18 . 0 Jul 9 Apr 16 Oct 9 .00 Oct 9 Apr 20 .00 .22 286 994 1979 77.7 1977 1992 1971 1974 1985 1971 1984 1970 1970 1984 RIO GRANDB DB MANATI BASIN 50035500 RIO GRANDB DB MANATI AT HIGHWAY 149 AT CIALBS, RP WATER-QUALITY RECORDS LOCATION.--Lat 18°20'46", long 66°28'06", at bridge on Highway 149, about 800 ft (244 m) upstream from confluence with Rio Cialitos, 0.5 mi (0.8 km) north of Ciales plaza. DRAINAGE AREA.--136 mi' (352 km 1 } this excludes the 6 mi' (15.5 km'} upstream from La go Bl Ouineo and Lago de Matrullas, flow from which is diverted to Rio Jacaguas. PERIOD OF RECORD.—Water years 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 21... DEC 30. .. FBB 1992 20... MAY 15. .. JUL 02. . . AUG 29. .. TIME 1130 1055 1005 1045 0930 1145 DIS- CHARGE, INST. CUBIC FEET PER SECOND 96 47 55 B400 93 87 PH SPB- WATER CIFIC WHOLE CON- FIELD TEMPER- DUCT- (STAND- ATURB ANCB ARD WATER (US/CM) UNITS) (DBG C) 240 265 250 134 330 443 7. 8. 8. 6. 8. 7. 0 5 1 8 0 5 26.0 24.0 25.0 23.5 29.0 29.0 TUR- BID- ITY (NTU) 17 4 6 57 2 0 .9 .4 .2 .50 OXYGEN, OXYGEN COLI- DIS- DEMAND, FORM, STREP- SOLVED CHEM- FECAL, TOCOCCI OXYGEN, (PER- ICAL 0.45 FECAL, DIS- CENT (HIGH UM-MF (COLS. SOLVED SATUR- LEVEL) (COLS./ PER (MG/L) ATI ON) (MG/L) 100 ML) 100 ML) 5 <24 7 6 6 7 .5 .0 .6 .8 .6 .8 67 98 84 79 74 86 <10 53000 <10 K72 <10 36 22 430 <10 200 <10 200 410 K170 K100 210 30 K150 DATE OCT 1991 21.. . DEC 30.. . FBB 1992 20.. . MAY 15.. . JUL 02.. . AUG 29.. . HARD- NESS CALCIUM TOTAL DIS- (MG/L SOLVED AS (MG/L MAGNE- SIUM, DIS- SODIUM, DIS- SOLVED SOLVED (MG/L (MG/L CACO3) AS CA) AS MG) AS NA) 95 24 64 16 91 23 8.6 13 SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY SIUM, WAT WH DIS- SOLVED (MG/L MG/L AS AS K) 0.6 1.9 5.8 9.1 0.5 1.7 CHLO- SULFATB RIDE, TOT FET SULFIDB DIS- DIS- FIBLD TOTAL SOLVED SOLVED (MG/L (MG/L (MG/L 8.1 12 0.5 1.9 CAC03 100 110 95 64 87 90 AS S) AS SO4) AS CL) <0.5 9.7 10 <0.5 7.2 12 9.0 14 DATE OCT 1991 21... DEC 30.. . FBB 1992 20... MAY 15.. . JUL 02.. . AUG 29... FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.30 -- -- 0.20 -- 0.10 SILICA, DIS- SOLVED (MG/L AS SIO2) 22 -- -- 20 -- 24 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 149 -- -- 110 -- 150 SOLIDS, DIS- SOLVED (TONS PER DAY) 38.9 -_ -- -- -- 35.2 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 3 1 12 24 8 11 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.360 0.200 -- 0.190 0.480 0.240 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.020 0.010 <0.010 0.050 0.010 0.010 NITRO- GEN, N02+N03 TOTAL (MG/L AS N) 0.380 0.210 0.200 0.240 0.490 0.250 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.040 0.020 0.010 0.080 0.030 0.040 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.26 -- -- -- 0.57 — K = non-ideal count B = estimate RIO GRANDB DB MANATI BASIN 50035500 RIO GRANDB DB MANATI AT HIGHWAY 149 AT CIALBS, PR—Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 99 DATE OCT 1991 21... DEC 30.. . FBB 1992 20.. . MAY 15... JUL 02... AOG 29.. . DATE OCT 1991 21... DEC 30... FBB 1992 20... MAY 15... JUL 02.. . AUG 29... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.30 <0.20 <0.20 <0.20 0.30 <0.20 IRON, TOTAL RECOV- ERABLE (DG/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) 0.68 — — -- 0.38 — LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N03) 3.0 -- -- -- 1.7 -- MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.110 0.070 0.050 0.140 0.070 0.050 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) ARSENIC TOTAL (UG/L AS AS) <1 -- _- <1 -- -- SELE- NIUM, TOTAL (UG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 — — <100 — -- SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) <10 — -- 20 -- -- ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 — — <1 — — CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) 1 -- -- <1 — -- PHENOLS TOTAL (DG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) 10 — — 10 — -- MBTHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 1300 2100 <1 50 100 <0.10 <0.10 <1 <1 <1 <1 <0.010 30 <0.010 O.C2 0.01 700 RIO GRANDB DB MANATI BASIN S003S9SO RIO CIALITOS AT HIGHWAY 649 AT CIALBS, PR HATER-QOALITY RECORDS LOCATION.--Lat 18°20'18", long 66°28'28", 100 ft (30 m) upstream from bridge on Highway 649, upstream from mouth/ and about 0.4 mi (0.6 km) west of Ciales plaza. DRAINAGE AREA.--17.0 mi» (44.0 km a ). PERIOD OP RECORD.--Hater years 1969-71, 1974 to current year. HATER-QOALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 0.7 mi (1.1 DATE OCT 1991 21... DEC 30. .. PBB 1992 20... RAY 15... JUL 02... AOG 29... OCT 21 DEC 30 PBB 20 RAY IS JUL 02 AOG 29 OCT 21 DEC 30 PBB 20 MAY IS JUL 02 AOG 29 K = DIS- PH OXYGEN, OXYGEN COLI- CHARGB, SPB- HATER DIS- DEMAND, PORM, STREP - INST. CIPIC WHOLE SOLVED CHEM- FECAL, TOCOCCI CUBIC CON- PIBLD TEMPER- TOR- OXYGEN, (PER- ICAL 0.45 PECAL, PBBT DUCT- (STAND- ATORB BID- DIS- CENT (HIGH OM-MP (COLS. TIME PER ANCB ARD HATER ITY SOLVED SATOR- LEVEL) (COLS./ PER SECOND (OS/CM) UNITS) (DBG C) (NTO) (MG/L) ATION) (MG/L) 100 ML) 100 ML) 1240 4.0 194 7.2 23.5 82 6.0 70 22 K60000 6800 1200 0.70 232 8.4 21.0 2.4 9.4 109 <10 K8SO 340 1110 3.0 236 8.1 22.5 1.7 8.8 101 <10 330 520 1245 3.6 225 7.1 26.0 2.0 7.8 95 <10 350 220 1045 5.0 420 8.3 26.5 13 8.5 86 <10 460 K870 1300 3.6 213 7.7 26.5 12 8.2 81 <10 K900 250 ALKA- HARD- NESS TOTAL (MG/L DATE AS CAC03 ) 1991 75 ... 1992 ... 80 ... 84 PLOO- RIDB, DIS- SOLVED DATE (MG/L AS P) 1991 <0.10 ... 1992 0.20 0.10 non- ideal count CALCIUM DIS- SOLVED (MG/L AS CA) 22 -- -- 23 -- 24 SILICA, DIS- SOLVED (MG/L AS SI 02) 19 — -- 27 -- 25 MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) 4.8 -- -- S.S -- 5.8 SOLIDS, SUM OP CONSTI- TUENTS, DIS- SOLVED (MG/L) 119 __ -- 135 -- 137 SODIOM, DIS- SOLVED (MG/L AS NA) 9.7 — -- 9.8 -- 9.9 SOLIDS, DIS- SOLVED (TONS PER DAY) 1.29 — — 1.31 — 1.33 SODIOM AD- SORP- TION RATIO 0.5 -- -- 0.5 -- 0.5 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 49 1 9 3 19 16 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 2.8 -- -- 2.0 — 1.8 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 1.34 0.540 -- 0.530 0.420 0.590 LINITY HAT HH TOT PET PIBLD MG/L AS CAC03 70 100 100 75 98 81 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.060 0.010 <0.010 0.010 0.010 0.010 SOLPIDE TOTAL (MG/L AS S) <0.5 — — <0.5 -- — — NITRO- GEN, NO2+N03 TOTAL (MG/L AS N) 1.40 O.SSO 0.480 0.540 0.430 0.600 SOLPATB DIS- SOLVED (MG/L AS SO4) 9.0 -- -- 6.3 -- 6.2 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.080 0.010 0.020 0.030 0.020 0.050 CHLO- RIDE, DIS- SOLVED (MG/L AS CD 9.7 -- -- 12 -- 11 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.62 -- — — -- — RZO GRANDB DB MANATI BASIN 50035950 RZO CZALZTOS AT HIGHWAY 649 AT CIALBS, PR—Continued WATER-QUALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 707 DATE OCT 1991 21... DEC 30... FBB 1992 20... MAY 15... JOL 02... AOG 29... DATE OCT 1991 21... DEC 30... FBB 1992 20... MAY 15.. . JOL 02... AOG 29... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.70 <0.20 <0.20 <0.20 <0.20 <0.20 IRON, TOTAL RECOV- ERABLE (OG/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) 2.1 ~ — — — — LEAD, TOTAL RECOV- ERABLE (OG/L AS PB) NZTRO- GEN, TOTAL (MG/L AS NO3) 9.3 — — -- -- -- MANGA- NESE, TOTAL RECOV- ERABLE (OG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.150 0.070 0.060 0.050 0.080 0.140 MERCURY TOTAL RECOV- ERABLE (OG/L AS HG) ARSENIC TOTAL (OG/L AS AS) <1 — — <1 -- -- SELE- NIUM, TOTAL (OG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 — — <100 ~ — SILVER, TOTAL RECOV- ERABLE (OG/L AS AG) BORON, TOTAL RECOV- ERABLE (OG/L AS B) 20 — — 20 — -- ZZNC, TOTAL RECOV- ERABLE (OG/L AS ZN) CADMZOM TOTAL RECOV- ERABLE (OG/L AS CD) <1 — — <1 — — CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (OG/L AS CR) 2 -- — <1 — — PHENOLS TOTAL (OG/L) COPPER, TOTAL RECOV- ERABLE (OG/L AS CO) 10 — ~ <10 — — MBTHY- LBNB BLOB ACTIVE SOB- STANCE (MG/L) 4000 110 40 40 <0.10 <0.10 10 <0.010 <0.010 0.02 0.02 102 RIO GRANDB DB MANATI BASIN 50038100 RIO GRANDB DB MANATI AT HIGHWAY 2 NEAR MANATI, PR LOCATION.--Lat 18 025'52", long 66°31'37", Hydrologic Unit 21010002, at bridge on Highway 2, and 2.3 mi (3.7 km) west of Manati. DRAINAGE AREA.--197 mi» (510 km 1 ), approximately, of which about 38 mi 1 (98 km1 ) is partly or entirely noncontributing, excludes 6.0 mi 1 (15.5 km1 ) upstream from Lago El Guineo and Lago de Matrullas. HATER-DISCHARGE RECORDS PERIOD OF RECORD.—1963-68 (annual maximum discharge only), February 1970 to current year. REVISED RECORDS.--WRD PR-86-1> 1970-71 (M), 1975, 1979, 1982-85 (P). GAGE.—Hater-stage recorder. Elevation of gage is 14 ft (4 m), from topographic map. Prior to 1968 crest-stage gage at same Site and datum 3.57 ft (1.09 m) lower. REMARKS.--Records fair except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. EXTREMES OUTSIDE PERIOD OF RECORD.—Approximate gage heights to gage datum of major floods, pointed out by local residents, are as follows: Sept. 13, 1928, 36.6 ft (11.16 m), Sept. 27, 1932, 36.3 ft (11.06 m), and Aug. 4, 1945, 34.3 ft (10.45 m) . DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 105 1540 2 101 1170 3 98 457 4 91 297 5 91 222 6 94 199 7 88 173 8 203 190 9 255 169 10 128 150 11 114 135 12 106 125 13 97 122 14 93 117 15 90 117 16 86 116 17 83 115 18 80 110 19 100 106 20 211 104 21 172 107 22 108 109 23 124 108 24 113 118 25 101 121 26 133 108 27 165 104 28 110 103 29 396 104 30 1320 99 31 1120 TOTAL 6176 6815 MEAN 199 227 MAX 1320 1540 MIN 80 99 AC-PT 12250 13520 CPSM 1.01 1.15 IN. 1.17 1.29 e Estimated STATISTICS OF MONTHLY MEAN MEAN 818 589 MAX 2958 1803 (WY) 1971 1971 MIN 161 123 (WY) 1987 1974 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC-PT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 96 96 98 97 97 96 93 93 92 100 97 92 90 91 90 87 87 85 82 82 277 el74 e!30 elOO e90 e86 e86 e90 e92 e92 e88 3146 101 277 82 6240 .52 .59 DATA 388 1498 1971 101 1992 FOR e82 e78 e74 e74 e8400 e8410 e940 e560 e440 e360 e350 e360 e320 e290 e250 e370 e340 e240 e200 e!80 el70 el54 el55 el54 el54 el40 e!37 el30 el30 el30 e!28 23900 771 8410 74 47410 3.91 4.51 FOR WATER 260 771 1992 105 1984 e!27 el23 179 168 151 139 252 206 184 155 144 162 151 135 126 123 117 114 111 111 108 108 105 102 101 103 101 99 95 ___ --- 3900 134 252 95 7740 .68 .74 YEARS 1970 205 444 1988 87.6 1984 95 91 91 89 89 88 85 83 148 126 120 107 90 85 82 81 84 112 116 100 89 84 87 84 77 123 111 509 282 509 168 4085 132 509 77 8100 .67 .77 - 1992 198 521 1972 68.4 1984 1991 CALENDAR YEAR 79921 219 3020 80 86 158500 1. 15. Jul 16 Oct 18 Dec 14 11 09 246 135 777 204 142 121 138 173 793 2130 472 283 219 184 165 221 552 281 626 2090 866 360 254 208 186 170 160 147 139 235 --- 12677 423 2130 121 25140 2.15 2.39 246 1920 547 301 217 333 275 192 160 150 141 136 240 170 243 210 316 803 624 1300 1060 482 2520 6280 1660 3250 2050 979 705 540 1440 29490 951 6280 136 58490 4.83 5.57 2770 2340 847 629 509 442 400 433 e400 e620 459 337 313 291 267 248 236 223 213 206 200 204 195 192 186 179 175 173 166 162 14015 467 2770 162 27800 2.37 2.65 156 153 194 173 154 148 143 160 197 157 145 142 142 165 151 149 151 136 133 131 129 122 119 133 138 116 108 107 106 98 95 4351 140 197 95 8630 .71 .82 131 123 112 112 167 220 175 124 114 108 188 136 114 105 112 119 108 93 87 93 296 196 130 106 111 127 126 112 101 91 88 4025 130 296 87 7980 .66 .76 85 78 84 86 102 139 118 158 216 155 108 93 85 76 72 69 78 90 90 656 176 119 106 181 168 167 115 103 91 98 --- 3962 132 656 69 7860 .67 .75 , BY HATER YEAR (WY) 364 986 1987 60.1 1984 FOR 1992 116542 318 8410 69 80 13600 28 43 231200 1 22 686 3178 1985 93.7 1989 HATER YEAR Jan 6 Sep 16 Sep 13 May 24 .61 May 24 Jan 16 .62 .01 251 747 1987 78.7 1977 165 577 1979 75.2 1984 HATER 381 756 17£ 55900 34 38 97200 33 33 276000 1 26 229 1644 1979 67.9 1984 YEARS 1970 - May 18 May 12 May 7 Oct 7 .79 Oct 7 May 12 .93 .28 438 1510 1979 127 1983 1992 1971 1974 1985 1984 1984 1985 1985 1984 703 RIO QRANDB DB MANATI BASIN 50038100 RIO QRANDB DB MANATI AT HIGHWAY 2 NEAR MANATI, PR—Continued (National stream-quality accounting network station) WATER-QUALITY RECORDS PERIOD OF RECORD.--Water year* 1969 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 04. .. DEC 31... FEB 1992 25... APR 22... JUN 23. .. AUQ 10. .. DATE OCT 1991 04. .. DEC 31. .. FBB 1992 25... APR 22... JUN 23... AUQ 10... DATE OCT 1991 04... DEC 31. .. FBB 1992 25... APR 22... JUN 23... AOG 10. . . TIME 0950 0920 1025 1000 1005 0935 MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) 7.6 8.2 8.4 8.6 7.8 8.0 SOLIDS, DIS- SOLVED (TONS PER DAY) 54.5 46.2 51.0 166 85.4 52.5 DIS- CHARGE, INST. CUBIC FEET PER SECOND 108 90 100 370 186 108 SODIUM, DIS- SOLVED (MG/L AS NA) 11 11 12 8.5 11 11 NITRO- GEN, N02+N03 DIS- SOLVED (MG/L AS N) 0.640 0.580 0.500 0.970 0.260 0.480 SPE- CIFIC CON- DUCT- ANCE (US/CM) 309 328 325 280 286 302 SODIUM AD- SORP- TION RATIO 0.4 0.4 0.4 0.4 0.4 0.4 NITRO- GEN, AMMONIA DIS- SOLVED (MG/L AS N) 0.030 0.090 0.030 0.040 0.070 0.400 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.6 7.7 7.5 6.7 7.2 7.2 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 1.8 1.7 1.9 2.1 2.0 2.5 NITRO- GEN, AMMONIA DIS- SOLVED (MG/L AS NH4) 0.04 0.12 0.04 0.05 0.09 0.52 TEMPER- ATURE WATER (DBG C) 27.5 23.0 25.0 25.0 28.0 27.0 ALKA- LINITY WAT WH TOT FBT FIELD MG/L AS CAC03 130 140 140 130 110 120 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.60 0.50 0.40 <0.20 0.30 0.60 TUR- BID- ITY (NTU) 15 -- 6.3 55 10 7.6 SULFATB DIS- SOLVED (MG/L AS 804) 9.3 8.2 14 15 7.4 6.8 PHOS- PHORUS TOTAL (MG/L AS P) 0.200 0.140 0.100 0.040 0.090 0.130 OXYGEN, DIS- SOLVED (MG/L) 7.0 3.8 8.0 6.3 5.2 5.4 CHLO- RIDE, DIS- SOLVED (MG/L AS CL) 12 13 17 8.7 14 15 PHOS- PHORUS DIS- SOLVED (MG/L AS P) 0.130 0.140 0.060 0.040 0.080 0.090 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 21000 4700 3500 4600 K18000 27000 FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.10 0.10 <0.10 <0.10 0.10 0.10 PHOS- PHORUS ORTHO, DIS- SOLVED (MG/L AS P) 0.120 0.090 0.060 0.040 0.090 0.070 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) K1500 K11000 4700 3600 2100' 1700 SILICA, DIS- SOLVED (MG/L AS SI 02) 20 20 16 28 20 20 PHOS- PHATE, ORTHO, DIS- SOLVED (MG/L AS P04) 0.37 0.28 0.18 0.12 0.28 0.21 HARD- NESS TOTAL (MG/L AS CAC03) 130 -- 140 100 120 130 SOLIDS, RESIDUE AT 180 DBG. C DIS- SOLVED (MG/L) 187 178 189 166 170 174 ALUM- INUM, DIS- SOLVED (UG/L AS AL) 20 -- <10 -- 10 20 CALCIUM DIS- SOLVED (MG/L AS CA) 40 -- 44 27 35 38 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 183 190 200 142 165 180 BARIUM, DIS- SOLVED (UG/L AS BA) 40 -- 43 — 41 48 K = non-ideal count 704 RIO GRANDE DB MANATI BASIN 50038100 RIO GRANDE DB MANATI AT HIGHWAY 2 NEAR MANATI, PR—Continued (National stream-quality accounting network station) WATER-QOALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 04... DEC 31... FEB 1992 25... APR 22... JUN 23... AUG 10... COBALT, DIS- SOLVED (UG/L AS CO) <3 -- <3 -- <3 <3 IRON, DIS- SOLVED (UG/L AS FE) 14 -- <3 -- 9 12 LITHIUM DIS- SOLVED (UG/L AS LI) <4 _- 4 -_ <4 <4 MANGA- MOLYB- NBSB, DENUM, DIS- DIS- SOLVED SOLVED (UG/L (UG/L AS MN) AS MO) 25 <10 — 27 <10 — 27 <10 25 <10 SBLB- 8TRON- NICKBL, NIUM, SILVER, TIUM, DIS- DIS- DIS- DIS- SOLVED SOLVED SOLVED SOLVED (UG/L (UG/L (UG/L (UQ/L AS NI) AS SB) AS AG) AS SR) 1 <1 <1.0 190 __ <1 <1 <1.0 210 — 1 <1 <1.0 170 <1 <1 <1.0 190 VANA- DIUM, DIS- SOLVED (UG/L AS V) 8 — <6 — <6 9 105 RIO GRANDB DB MANATI BASIN 50038100 RIO GRANDB DB MANATI AT HIGHWAY 2 NEAR MANATI, PR—Continued (National stream-quality accounting network station) WATBR-QOALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT DATE OCT 1991 04... DEC 1992 31... FBB 25... APR 22. . . JUN 23... AUG 10... TIME 0950 0920 1025 1000 10 Ob 0935 STREAM- FLOW, INSTAN- TANEOUS (CFS) 108 90 100 370 186 108 SEDI- MENT, SUS- PENDED (MG/L) 86 65 68 123 35 38 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 25 16 18 123 18 11 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 96 93 86 91 89 87 PESTICIDE ANALYSES DATE JUN 1992 23... TIME 1005 PCB, TOTAL (UG/L) ALDRIN, TOTAL (UG/L) <0.010 CHLOR- DANE, TOTAL (UG/L) DDD, TOTAL (UG/L) DDE, TOTAL (UG/L) DOT, TOTAL (UG/L) DI- AZINON, TOTAL (UG/L) DI- ENDO- <0.010 <0.010 <0.010 BLDRIN SULFAN, TOTAL TOTAL (UG/L) (UG/L) <0.01 <0.010 <0.010 DATE JUN 1992 23... DATE JUN 1992 23... ENDRIN WATER UNFLTRD RBC (UG/L) <0.010 PARA- THION, TOTAL (UG/L) BTHION, TOTAL (UG/L) <0.01 NAPH- THA- LENES, POLY- CHLOR. TOTAL (UG/L) HBPTA- CHLOR, TOTAL (UG/L) <0.010 PBR- THANB TOTAL (UG/L) HEPTA- CHLOR BPOXIDB TOTAL (UG/L) <0.010 TOX- APHENB, TOTAL (UG/L) LZNDANB TOTAL (UG/L) <0.010 TOTAL TRI- THION (UG/L) MALA- THION, TOTAL (UG/L) <0.01 2,4-D, TOTAL (UG/L) METH- OXY- CHLOR, TOTAL (UG/L) <0.01 2,4,5-T TOTAL (UG/L) METHYL PARA- THION, TOTAL (UG/L) <0.01 2, 4-DP TOTAL (UG/L) MIRBX, TOTAL (UG/L) <0.01 SILVBX, TOTAL (UG/L) <0.01 <0.10 <0.01 <0.01 <0.01 <0.01 <0.01 706 LACUNA TORTUGUERO BASIN 50038200 LAGDNA TORTOGOBRO OOTLBT NEAR VBGA BAJA, PR HATER-QUALITY RECORDS LOCATION.--Lat 18°28'29", long 66°26'SO-, at bridge on Highway 686, 4.2 mi (6.8 km) northeast of 4.4 mi (7.1 km) northwest of Vega Baja plaza. DRAINAGE AREA.--Indeterminate. PERIOD OF RECORD.--Hater years 1964-66, 1969-71, 1974 to current year. HATER-QUALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 Manati, and DATE OCT 1991 10... DEC 06... FEB 1992 21... APR 13... JON 09... AD6 14... DATE OCT 1991 10... DEC 06.. . FBB 1992 21... APR 13... JON 09... AOG 14... TIME 1600 0840 1015 1000 0835 0745 SOLFIDB TOTAL (MQ/L AS S) <0.5 -- -- <0.5 -- -- DIS- CHARGE, IN ST. COBIC FEET PER SECOND 17 15 8.8 6.0 17 2.8 RESIDUE TOTAL AT 105 DEG. C, SUS- PENDED (MG/L) 2 10 6 22 8 6 SPE- CIFIC CON- DUCT- ANCE (OS/ CM) 1400 1480 1370 1520 1400 1380 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.390 0.540 0.460 0.370 0.310 0.220 PH HATER WHOLE FIELD (STAND- ARD UNITS) 8.2 7.7 7.9 7.7 7.9 7.1 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.010 0.020 0.020 0.010 0.010 0.010 TEMPER- ATURE HATER (DBG C) 30.0 25.5 26.0 27.5 29.5 29.0 NITRO- GEN, N02+N03 TOTAL (MG/L AS N) 0.400 0.560 0.480 0.380 0.320 0.230 OXYGEN, DIS- SOLVED (MG/L) 8.3 6.9 6.9 6.6 6.4 3.8 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.230 0.360 0.240 0.260 0.160 0.230 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 38 34 32 40 36 31 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.67 0.74 0.56 0.84 0.74 0.87 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K30 K12 K4 K56 10 430 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.90 1.1 0.80 1.1 0.90 1.1 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 23 K40 K16 310 50 110 NITRO- GEN, TOTAL (MG/L AS N) 1.3 1.7 1.3 1.5 1.2 1.3 ALKA- LINITY HAT WH TOT FBT FIELD MG/L AS CAC03 98 120 120 110 100 100 NITRO- GEN, TOTAL (MG/L AS NO3) 5.8 7.3 5.7 6.6 5.4 5.9 BORON, COPPER, IRON, MANGA- NESE, ZINC, MBTHY- LBNB DATE OCT 1991 10... DEC 06.. . FEB 1992 21.. . APR 13... JUN 09... AUG 14.. . PHOS- PHORUS TOTAL (MG/L AS P) 0.010 <0.010 <0.010 0.010 <0 • 0X0 <0 • 0X0 TOTAL RECOV- ERABLE (UG/L AS B) 150 -- -- 90 -- -- TOTAL RECOV- ERABLE (UG/L AS CU) 10 -- -- 30 -- -- TOTAL RECOV- ERABLE (UG/L AS FE) <10 -- -- 70 -- -- TOTAL RECOV- ERABLE (UG/L AS MN) <10 -- -- 10 -- -- TOTAL RECOV- ERABLE (UG/L AS ZN) <10 -- -- <10 -- -- CYANIDE TOTAL PHENOLS (MG/L TOTAL AS CN) (UG/L) <0.010 3 __ -- <0.010 2 __ -- BLUB ACTIVE SUB* STANCE (MG/L) 0.10 -- -- 0.09 -- -- non-ideal count 107 Oroinog* feounctoyJ X J V '' * ° <** !s Pla EXPLANATION ± 038320 SURFACE-WATER STATION AND NUMBER V 0397 QUALITY-OF-WATER STATION AND NUMBER • 213 WELL AND WELL NUMBER r 0123456 KILOMETERS i01234 MILES Figure 17--Rio Cibuco basin. 708 RIO CIBUCO BASIN 50038320 RIO CIBDCO BELOW COROZAL, PR LOCATION.—Lat 18°21'13", long 66°20'07", Hydrologic Unit 21010001, on right bank, 150 ft (46 m) downstre Rio Corozal, and 1.4 ml (2.3 km) northwest of Corozal. an from DRAINAGE AREA.—15.1 mi* (39.1 km 9 ) WATER-DISCHARGE RECORDS PERIOD OF RECORD.—May 1969 to current year. GAGE.—Water-stage recorder. Elevation of gage is 195 ft (59 m), from topographic map. REMARKS.—Records fair. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR MAY JUN JUL AUG 1 10 164 2 8.0 84 3 7.2 55 4 8.8 50 5 12 48 6 8.8 36 7 7.4 24 8 26 21 9 19 16 10 11 14 11 9.0 13 12 8.2 14 13 7.2 14 14 7.3 12 15 6.4 12 16 4.9 13 17 4.6 12 18 4.6 11 19 10 11 20 8.9 12 21 6.2 14 22 7.4 16 23 11 14 24 7.0 36 25 79 16 26 21 13 27 13 13 28 15 21 29 159 13 30 153 12 31 109 —— TOTAL 769.9 804 MEAN 24.8 26.8 MAX 159 164 MIN 4.6 11 AC-FT 1530 1590 CFSM 1.64 1.77 IN. 1.90 1.98 11 12 13 13 11 10 10 11 14 13 10 10 9.8 12 9.4 11 9.9 9.3 9.2 21 18 12 11 11 10 10 11 13 13 12 11 361.6 11.7 21 9.2 717 .77 .89 STATISTICS OF MONTHLY MEAN DATA MEAN 43.6 46.6 MAX 135 155 (WY) 1991 1971 MIN 8.05 8.15 (WY) 1979 1974 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 37.1 169 1971 6.86 1979 FOR 9.9 10 10 9.9 1260 278 58 30 25 38 28 27 33 27 23 39 36 25 22 19 16 17 16 15 13 13 12 14 12 12 11 2158.8 69.6 1260 9.9 4280 4.61 5.32 FOR WATER 25.7 69.6 1992 8.36 1978 11 11 27 16 13 12 11 11 9.3 9.9 10 15 11 11 12 11 11 10 11 11 11 12 10 11 12 12 11 10 9.8 ___ --- 343.0 11.8 27 9.3 680 .78 .85 YEARS 1969 22.0 51.3 1988 8.11 1984 9.2 9.2 9.0 9.3 9.8 8.9 9.2 15 11 9.6 8.8 8.5 7.7 7.1 8.0 7.3 9.3 13 12 8.3 7.7 8.0 8.2 7.2 7.3 6.9 133 45 29 18 20 480.5 15.5 133 6.9 953 1.03 1.18 - 1992 23.7 65.1 1981 4.36 1984 1991 CALENDAR YEAR 7238. 19. 290 4. 5. 14360 1. 17. 32 13 6. 0 8 Mar 26 6 Oct 17 6 Sep 5 31 83 8 17 22 17 12 12 12 18 14 12 14 12 11 11 11 11 9.6 10 9.6 9.4 9.4 9.1 8.8 8.9 9.2 8.9 8.9 9.0 8.7 9.6 31—— 366.1 12.2 31 8.7 726 .81 .90 113 91 23 14 12 56 18 13 11 11 11 10 10 9.5 9.9 20 11 15 106 38 83 36 92 120 40 89 60 34 30 23 20 1229.4 39.7 120 9.5 2440 2.63 3.03 18 17 16 14 13 13 13 14 15 17 15 14 13 13 13 12 12 11 11 9.1 9.5 9.7 9.4 8.8 8.5 8.5 8.2 8.2 8.1 8.1 —— 360.1 12.0 18 8.1 714 .79 .89 7.9 7.7 7.8 7.7 8.2 7.5 7.5 16 16 12 12 11 15 24 15 13 13 12 18 14 12 11 11 15 11 10 9.5 9.8 11 10 10 365.6 11.8 24 7.5 725 .78 .90 10 12 12 147 61 46 20 15 13 11 9.9 9.4 9.6 21 13 14 9.6 9.3 8.8 15 11 9.1 8.6 7.9 8.2 8.8 9.1 8.6 9.0 8.0 9.8 564.7 18.2 147 7.9 1120 1.21 1.39 7.6 9.1 11 12 19 20 14 13 12 11 10 10 9.4 10 10 11 13 12 77 59 19 13 16 11 16 12 9.4 9.0 8.6 9.6 473.7 15.8 77 7.6 940 1.05 1.17 , BY WATER YEAR (WY) 33.6 111 1973 3.32 1984 FOR 1992 8277. 22. 1260 4. 6. 11900 19. 3. 16420 1. 20. 35 12 8. 46.2 157 1986 3.20 1977 WATER YEAR 4 6 Jan 5 6 Oct 17 2 Oct 12 Jan 5 32 Jan 5 8 Oct 18 50 39 2 15.2 44.4 1987 2.26 1977 11.9 34.6 1979 2.93 1977 WATER 29 56 13 2370 1 1 13600 19 21180 1 26 50 13 5 17.1 50.8 1979 3.44 1978 YEARS 1969 .2 .5 .6 May .3 Jul .4 Jul Nov .80 Nov .94 .31 .9 26.5 73.2 1979 6.54 1978 - 1992 1971 1984 18 1985 24 1977 20 1977 7 1979 7 1979 709 RIO CIBOCO BASIN 50038320 RIO CIBOCO BELOW COROZAL, PR—Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1969-76, 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 17... DEC 09... FEB 1992 26... JUN 22.. . AUG 14... DATE OCT 1991 17.. . DEC 09... FEE 1992 26... JUN 22.. . AUQ 14.. . DATE OCT 1991 17.. . DEC 09... FBB 1992 26.. . JUN 22. .. AUG 14... K = non- ideal TIME 1015 1345 1025 1100 0835 HARD- NESS TOTAL (MG/L AS CACO3 ) 160 -- -- 140 140 FLUO- RIDE, DIS- SOLVED (MG/L AS F) 0.10 -- -- 0.20 0.20 count DIS- CHARGE, IN ST. CUBIC FEET PER SECOND 4.6 15 10 10 11 CALCIUM DIS- SOLVED (MG/L AS CA) 41 __ — 36 35 SILICA, DIS- SOLVED (MG/L AS SI 02) 33 -- -- 29 32 SPE- CIFIC CON- DUCT- ANCE (US/CM) 426 367 360 366 365 MAGNE- SIUM, DIS- SOLVED (MG/L AS MO) 13 -_ -- 12 12 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 243 __ -- 218 220 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.9 8.0 7.7 7.8 7.4 SODIUM, DIS- SOLVED (MG/L AS NA) 27 -- _- 18 18 SOLIDS, DIS- SOLVED (TONS PER DAY) 3.06 -_ -- 6.07 6.53 TEMPER- ATURE WATER (DBG C) 25.5 24.0 25.0 27.5 25.0 SODIUM AD- SORP- TION RATIO 0.9 -- _- 0.7 0.7 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) <1 24 1 4 2 TUR- BID- ITY (NTU) 3.0 9.6 1.1 1.8 1.5 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 4.4 _- -- 3.2 3.5 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 3.71 3.67 2.78 2.28 0.990 OXYGEN, DIS- SOLVED (MG/L) 7.6 7.9 8.6 7.5 6.2 ALKA- LINITY WAT WH TOT FET FIELD MG/L AS CACO3 130 110 120 120 120 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.090 0.030 0.020 0.020 0.110 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 14 19 18 <10 <10 SULFIDB TOTAL (MG/L AS S) •<0.5 — — <0.5 — - NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 3.80 3.70 2.80 2.30 1.10 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 410 K80000 6900 2400 8700 SULFATE DIS- SOLVED (MG/L AS SO4) 17 -- -- 19 16 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.150 0.040 0.030 0.050 0.090 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 280 30000 870 K210 740 CHLO- RIDE, DIS- SOLVED (MG/L AS CL) 30 — -- 29 26 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.45 0.36 0.17 0.35 0.21 110 DATE OCT 1991 17... DEC 09... FBB 1992 26.. . JUN 22... AUG 14... DATE OCT 1991 17.. . DEC 09.. . FBB 1992 26.. . JUN 22... AUG 14.. . RIO CIBOCO BASIN 50038320 RIO CIBUCO BELOW COROZAL, PR--Continued HATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.60 0.40 0.20 0.40 0.30 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) 4.4 4.1 3.0 2.7 1.4 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N03) 19 18 13 12 6.2 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 1.00 0.810 0.540 0.520 0.370 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) ARSENIC TOTAL (UG/L AS AS) <1 -- -- <1 -- SELE- NIUM, TOTAL (UG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 — — <100 -- SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) 40 -- -- 30 -- ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 — — <1 -- CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) <1 -- -- <1 -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) <10 — — <10 -- MBTHY- LBNE BLUB ACTIVE SUB- STANCE (MG/L) 80 170 30 50 <0.10 <0.10 <0.010 <0.010 12 0.07 0.04 RIO CIBOCO BASIN ' ' ' 50039500 RIO CIBUCO AT VEGA BAJA, PR LOCATION.--Lat 18«26'53", long 66«22'29", Hydrologic Unit 21010002, on left bank, at bridge on Hwy 2, 0.6 mi (1.0 km) downBtream from Rio Indio, and 0.8 mi (1.3 km) east of Vega Baja. DRAINAGE AREA.--99.1 mi* (256.7 km*), of which 25.4 mi* (65.8 km*), doe« not contribute directly to surface runoff. NATBR-DISCHARQB RECORDS PERIOD OF RECORD.—January 1973 to current year. OAQB.--Nater-Btage recorder. Datum of gage i« 7.79 ft (2.374 m) above mean tea level. REMARKS.--Record* fair except thoae for estimated daily diachargea, which are poor. Qage-height and precipitation •atellite telemetry at •tation. EXTREMES OOTSIDB PERIOD OF RECORD.--Flood of Dec. 11, 1965 reached a atage of 26.2 ft (7.99 m), datum unknown, discharge about 28,000 ftV« (793 mV«). DISCHARGE, CUBIC FEET PER SECOND, NATBR YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV JAN FBB MAR APR MAY JUN JUL AUG SEP 1 40 280 2 28 424 3 23 174 4 20 129 5 26 136 6 32 99 7 20 66 8 22 58 9 73 45 10 30 37 11 22 31 12 20 28 13 18 29 14 17 28 15 17 26 16 17 25 17 15 26 18 16 24 19 22 22 20 30 23 21 22 26 22 18 74 23 28 32 24 26 132 25 43 53 26 134 34 27 33 31 28 43 29 29 365 51 30 785 34 31 321 TOTAL 2326 2206 MEAN 75.0 73.5 MAX 785 424 MIN 15 22 AC-FT 4610 4380 CFSM .76 .74 IN. .87 .83 e Estimated STATISTICS OF MONTHLY MEAN MEAN 171 189 MAX 559 523 (WY) 1986 1980 MIN 45.9 40.0 (WY) 1974 1974 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 32 32 37 52 42 38 36 43 46 65 44 40 39 45 43 36 38 35 33 37 140 58 46 41 38 36 36 42 51 39 36 1376 44.4 140 32 2730 .45 .52 DATA 184 1316 1982 30.5 1979 FOR 34 32 31 30 381 2930 355 201 138 205 156 113 120 100 83 78 199 106 78 68 64 60 58 54 54 58 52 48 49 45 43 6023 194 2930 30 11950 1.96 2.26 FOR WATER 96.5 209 1988 36.3 1984 42 42 43 127 58 45 43 42 38 36 36 41 37 35 35 35 32 30 31 31 31 34 32 29 31 30 31 30 29 ___ --- 1136 39.2 127 29 2250 .40 .43 YEARS 1973 92.3 190 1988 32.6 1977 28 26 28 29 26 25 23 23 43 27 24 23 22 22 23 22 25 38 38 30 25 24 23 24 22 22 128 296 106 63 116 1394 45.0 296 22 2760 .45 .52 - 1992 95.9 339 1990 24.3 1984 1991 CALENDAR YEAR 29965 82. 1030 15 17 59440 . 11. 168 48 22 1 Jul 16 Oct 17 Oct 12 83 25 120 45 166 49 34 31 46 53 43 51 46 34 31 29 26 26 29 28 58 31 29 25 25 23 23 23 23 23 28 136 --- 1334 44.5 166 23 2650 .45 .50 91 630 115 52 34 122 74 37 28 25 23 21 20 20 19 33 61 39 191 363 250 307 240 642 252 382 e490 e250 e!63 158 380 5512 178 642 19 10930 1.79 2.07 282 222 155 103 74 61 70 64 67 68 75 57 48 43 40 39 38 38 37 36 35 36 35 33 31 29 28 31 28 28 1931 64.4 282 28 3830 .65 .72 29 27 29 28 27 28 25 35 78 52 40 37 43 92 98 58 50 42 71 107 41 32 30 44 48 29 27 31 27 25 24 1354 43.7 107 24 2690 .44 .51 24 23 26 187 312 314 99 70 71 62 43 36 37 32 71 42 35 30 27 26 60 31 27 25 29 28 28 25 25 26 32 1903 61.4 314 23 3770 .62 .71 25 e25 e29 e31 e42 e45 e35 e31 e30 31 33 30 29 28 27 28 28 40 77 1210 186 79 64 77 66 100 47 38 34 32 2577 85.9 1210 25 5110 .87 .97 , BY WATER YEAR (WY) 160 671 1987 16.2 1984 FOR 1992 29072 79 2930 15 17 7710 16 14 57660 10 155 36 23 210 655 1985 24.7 1977 WATER YEAR .4 Jan 6 Oct 17 Oct 12 Jan 6 . 67 Jan 6 Oct 17 .80 .91 76.9 245 1987 12.8 1977 53.9 162 1979 15.5 1977 WATER 129 236 49 14600 7 8 34000 19 6 93220 1 17 227 60 25 85.3 461 1979 21.2 1978 YEARS 1973 - .3 Dec 13 .4 Jul 24 .5 Jul 21 Apr 12 .10 Apr 12 .1 Jul 24 .30 .64 121 450 1979 27.3 1991 1992 1982 1974 1981 1977 1977 1987 1987 1977 112 RIO CIBDCO BASIN 50039500 RIO CIBDCO AT VEGA BAJA, PR—Continued WATER-QUALITY RECORDS PERIOD OP RECORD.--Water year* 1972 to current year. WATER QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 01... DEC 06.. . PEB 1992 21... ODN 09.. . AUG 14... DATE OCT 1991 01.. . DEC 06.. . FEE 1992 21... ODN 09... AUG 14.. . DATE OCT 1991 01.. . DEC 06... PEB 1992 21.. . ODN 09.. . AUG 14... TIME 1630 1145 1245 1100 0940 HARD- NESS TOTAL (MG/L AS CAC03 ) 190 -- -- 180 190 PLUO- RIDE, DIS- SOLVED (MG/L AS P) 0.20 -- -- 0.10 0.10 DIS- CHARGE, INST. CUBIC FEET PER SECOND 44 37 35 73 32 CALCIUM DIS- SOLVED (MG/L AS CA) 56 — — 57 58 SILICA, DIS- SOLVED (MG/L AS SI02) 19 — -- 19 20 SPE- CIFIC CON- DUCT- ANCE (US/CM) 427 445 404 441 451 MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) 12 -- -- 9.4 10 SOLIDS, SUM OP CONSTI- TUENTS, DIS- SOLVED (MG/L) 273 -- -- 252 260 PH WATER WHOLE FIELD (STAND- ARD UNITS) 8.0 7.9 7.9 7.9 7.5 SODIUM, DIS- SOLVED (MG/L AS NA) 42 — -_ 18 18 SOLIDS, DIS- SOLVED (TONS PER DAY) 32.5 — -- 49.3 22.5 TEMPER- ATURE WATER (DEG C) 26.5 25.0 24.5 26.5 28.0 SODIUM AD- SORP- TION RATIO 1 __ _- 0.6 0.6 RESIDUE TOTAL AT 105 DEG. C, SUS- PENDED (MG/L) 4 14 7 <1 7 TUR- BID- ITY (NTU) 1.7 3.4 2.1 6.6 2.7 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 4.7 — -_ 4.1 4.0 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 1.48 1.78 1.75 1.27 1.36 OXYGEN, DIS- SOLVED (MG/L) 7.1 6.6 8.0 6.6 3.8 ALKA- LINITY WAT WH TOT PET FIELD MG/L AS CACO3 160 170 160 170 180 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.020 0.020 0.050 0.030 0.040 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) <10 11 <10 14 <10 SULPIDE TOTAL (MG/L AS S) <0.5 -- — <0.5 — — NITRO- GEN, N02+N03 TOTAL (MG/L AS N) 1.50 1.80 1.80 1.30 1.40 COLI- PORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 2400 390 290 400 28000 SULFATE DIS- SOLVED (MG/L AS S04) 11 __ -- 16 17 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.040 0.050 0.020 0.030 0.030 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 2700 330 K150 380 400 CHLO- RIDE, DIS- SOLVED (MG/L AS CL) 32 — — 26 27 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.16 0.15 0.18 0.17 -- K 3 non- ideal count 113 RIO CIBDCO BASIN 50039500 RIO CIBDCO AT VBOA BAJA, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 01... DEC 06... PEB 1992 21... JDN 09... AUG 14... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.20 0.20 0.20 0.20 <0.20 NITRO- GEN, TOTAL (MG/L AS N) 1.7 2.0 2.0 1.5 -- NITRO- GEN, TOTAL (MG/L AS NO3) 7.5 8.9 8.9 6.6 -- PHOS- PHORUS TOTAL (MG/L AS P) 0.380 0.390 0.370 0.230 0.260 ARSENIC TOTAL (UG/L AS AS) <1 _- -- <1 -- BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 _- -- <100 -- BORON, TOTAL RECOV- ERABLE (UG/L AS B) -- -. -. 30 -. CADMIUM TOTAL RECOV- ERABLE (UQ/L AS CD) 1 -- — <1 -- CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) 1 -- -- <1 -- COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) <10 — — <10 -- DATE OCT 1991 01... DEC 06... FBB 1992 21... JUN 09... AUG 14... IRON, TOTAL RECOV- ERABLE (UG/L AS FB) LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) SELE- NIUM, TOTAL (UG/L AS SB) SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CYANIDE TOTAL (MG/L AS CN) PHENOLS TOTAL (UG/L) MBTHY- LBNB BLUB ACTIVE SUB- STANCE (MG/L) 200 430 30 30 •cO.10 <0.10 <1 <1 <1 <1 10 <0.010 10 <0.010 <1 0.05 0.03 114 THIS PAGE WAS LEFT BLANK INTENTIONALLY EXPLANATION A 0460 SURFACE-WATER STATION AND NUMBER W 0430 QUALITY-OF-WATER STATION AND NUMBER V0399 QUALITY-OF-WATER PARTIAL RECORD STATION AND NUMBER 0 216 WELL AND WELL NUMBER • 039990 LAKE-ELEVATION STATION "\ i 1 V ' ~j! \ ^^.. v y™1"' x > nQQQf^n «_•*"' * I—-•-"^>^_... ("^ / "^Z.^—riJf, a / \,^ /v' ' -4 039990 V «!* Pa*'''!*" \x /i %V S bo*in Soloes iNtgus! &c»s 01 23456 KILOMETERS 01 234 Figure 18~Rio de la Plata basin. 116 RIO DB LA PLATA BASIN 50039990 LAGO CARITB AT GATS TOWER LOCATION. — Lat 18°03'46", long 66°05'58", Hydrologic Unit 21010005, on top of a concrete tower at diversion tunnel on Carite Reservoir, 0.7 mi (1.1 km) northwest from Bscuela Carite Chino, 1.2 mi (1.9 km) northeast from Central Hidroelectrica de Carite Num. 1 and 1.8 mi (2.9 km) northeast from Bscuela Segunda Unidad. DRAINAGE AREA. --8. 20 mi* (21.24 km'). ELEVATION RECORDS PERIOD OF RECORD.— May 1989 to current year. GAGE. — Water stage recorder. Datum of gage is mean sea level. REMARKS. — Lago Carite Dam was completed in 1913. The operation of the reservoir is controlled by the utilization of water to meet the demand* for domestic, industrial and agricultural purposes in the Guayama Area. The dam is an earthfill with crest elevation of 1,806 ft (550 m) above mean sea level, with a structural height of 104 ft (32 m) and a lenght of 500 ft (152 m) . The dam ha* a capacity of approximately 11,310 acre-feet (13.9 ha?). The Dam is operated by the Puerto Rico Electric and Power Authority. Gage-height and precipitation satellite telemetry at station. EXTREMES OBSERVED FOR PERIOD OF RECORD. —Maximum elevation 1,787.61 ft (544.86 m) , Jan. 5, 1992; minimum elevation, 1,761.48 ft (536.90 m) , June 13, 14, 1990. EXTREMES FOR CURRENT YEAR .- -Maximum elevation 1,787.61 ft (544.86 m) , Jan. 5; minimum elevation, 1,776.26 ft (541.40 m), Oct. 1. Capacity Table (baaed on Data from Puerto Rico Electric Power Authority) Contents, in acre-feet Elevation, in feet Elevation, in feet 1,746 0 1,760 2,471 1,769 4,561 1,775 1,780 1,790 Contents, in acre-feet 6,194 7,704 11,048 DAY ELEVATION (FEET NGVD), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY OBSERVATION AT 24:00 VALUES OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN MAX MIN 1776.37 1776.68 1776.75 1776.80 1776.84 1776.87 1776.88 1776.90 1776.94 1776.95 1776.98 1776.99 1777.01 1777.02 1777.04 1777.06 1777.08 1777.08 1777.08 1777.08 1777.08 1777.08 1777.08 1777.07 1777.07 1777.06 1777.06 1777.05 1777.02 1776.98 1776.92 1776.96 1777.08 1776.37 1776.89 1776.86 1776.82 1776.81 1776.77 1776.84 1777.73 1778.84 1779.20 1779.32 1779.32 1779.32 1779.27 1779.27 1779.29 1779.28 1779.26 1779.23 1779.20 1779.20 1779.19 1779.25 1779.28 1779.79 1779.86 1779.90 1780.27 1780.57 1780.69 1780.72 —— 1778.94 1780.72 1776. 77 1780.79 1780.83 1780.94 1781.03 1781.05 1781.07 1781.06 1781.08 1781.08 1781.07 1781.06 1781.08 1781.07 1781.02 1781.04 1781.03 1781.04 1781.01 1781.00 1781.12 1781.10 1781.06 1781.05 1781.03 1781.01 1780.99 1780.96 1780.94 1780.92 1780.93 1780.96 1781.01 1781.12 1780.79 1780.98 1780.96 1780.94 1780.90 1786.50 1782.49 1781.93 1781.84 1781.86 1781.87 1781.86 1781.84 1781.82 1781.82 1781.80 1781.80 1781.79 1781.77 1781.75 1781.74 1781.72 1781.71 1781.69 1781.72 1781.73 1781.72 1781.71 1781.71 1781.69 1781.68 1781.65 1781.84 1786.50 1780.90 1781.63 1781.61 1781.59 1781.57 1781.57 1781.75 1781.78 1781.77 1781.74 1781.72 1781.68 1781.64 1781.61 1781.60 1781.59 1781.56 1781.54 1781.50 1781.49 1781.47 1781.45 1781.45 1781.43 1781.43 1781.43 1781.47 1781.46 1781.44 1781.42 ___ 1781.56 1781.78 1781.42 1781.38 1781.38 1781.35 1781.33 1781.31 1781.30 1781.31 1781.26 1781.24 1781.20 1781.17 1781.14 1781.10 1781.10 1781.07 1781.04 1781.08 1781.06 1781.02 1780.98 1780.96 1780.92 1780.92 1780.86 1780.82 1780.78 1780.74 1780.71 1780.67 1780.62 1780.70 1781.05 1781.38 1780.62 1780.78 1780.74 1780.64 1780.57 1780.50 1780.47 1780.36 1780.13 1780.01 1779.85 1779.72 1779.90 1779.77 1779.87 1779.69 1779.62 1779.48 1779.40 1779.57 1779.54 1779.62 1779.64 1779.62 1779.59 1779.57 1779.50 1779.49 1779.46 1779.44 1779.42 —— 1779.86 1780.78 1779.40 1779.20 1779.15 1779.03 1778.90 1778.77 1778.69 1778.68 1778.50 1778.49 1778.35 1778.26 1778.13 1778.04 1778.25 1778.17 1778.20 1778.08 1777.97 1777.63 1777.47 1777.27 1777.14 1778.93 1779.99 1780.48 1781.39 1781.25 1781.13 1781.00 1780.90 1780.78 1778.97 1781.39 1777.14 1780.68 1780.55 1780.40 1780.42 1780.29 1780.20 1780.10 1780.02 1780.40 1780.78 1781.06 1781.84 1781.97 1781.82 1781.74 1781.69 1781.69 1781.65 1781.62 1781.63 1781.88 1781.73 1781.67 1781.62 1781.59 1781.58 1781.57 1781.56 1781.55 1781.53 —— 1781.23 1781.97 1780.02 1781.53 1781.53 1781.52 1781.52 1781.53 1781.52 1781.50 1781.55 1781.54 1781.52 1781.58 1781.55 1781.47 1781.46 1781.50 1781.47 1781.52 1781.49 1781.48 1781.49 1781.47 1781.53 1781.49 1781.46 1781.45 1781.42 1781.40 1781.37 1781.35 1781.32 1781.29 1781.48 1781.58 1781.29 1781.27 1781.33 1781.30 1781.33 1782.68 1781.89 1781.71 1781.61 1781.55 1781.52 1781.55 1781.49 1781.46 1781.40 1781.47 1781.43 1781.44 1781.40 1781.39 1781.36 1781.25 1781.18 1781.11 1780.84 1780.72 1780.60 1780.45 1780.36 1780.22 1780.10 1779.99 1781.21 1782.68 1779.99 1779.87 1779.75 1779.65 1779.56 1779.40 1779.36 1779.21 1779.10 1779.04 1778.94 1778.80 1778.64 1778.52 1778.37 1778.18 1778.16 1778.17 1778.14 1778.40 1781.03 1781.44 1781.30 1781.18 1781.04 1781.00 1780.90 1780.79 1780.67 1780.57 1780.78 1779.67 1781.44 1778.14 CAL YR 1991 WTR YR 1992 MEAN 1777. MEAN 1780. 75 MAX 1782.01 MIN 1772.93 31 MAX 1786.50 MIN 1776.37 RIO DB LA PLATA BASIN 50043000 RIO DB LA PLATA AT PROYBCTO LA PLATA, PR 117 LOCATION.--Lat 18«09'37", lono 66<>13'44", Hydrologic Onit 21010005, at upstream side of bridge on Highway 173, 0.4 ml (0.6 km) northeast of Proyecto La Plata, and 2.S mi (4.0 km) upstream from Rio Osabon. DRAIHAGB AREA.--63.0 mi* (163.3 km*), excludes 8.2 mi* (21.1 km*) upstream from Carite Reservoir, the flow of which is diverted to Rio Quamani. WATER-DISCHARGE RECORDS PERIOD OF RECORD.—19S8 (occasional measurements only), February 19S9 to March 1960 (monthly measurements only). April 1960 to current year. CAGE.—Water-stage recorder. Elevation of gage is 8SO ft (2S9 m), from topographic map. Prior to Mar. 29, 1961, wire-weight gage read twice daily at same site and datum. REMARKS.--Records poor. The Puerto Rico Aqueduct and Sewer Authority operates a pumping plant about 5 mi (8 km) upstream which can divert as much as 23 ft1/* (0.6S mVs) into Cidra Reservoir. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VAL0BS DAY OCT NOV DBC JAN FBB MAR APR MAY JUN JOL AOG SEP 1 e!6 e49 2 el? e38 3 e!2 e28 4 ell e!9 S e!7 e!3 6 ell e24 7 eSS e32 8 e2S e35 9 el3 e23 10 ell el4 11 elO el2 12 e97 ell 13 e9.0 e9.4 14 e8.8 e9.6 IS e9.0 e8.6 16 e8.8 e!4 17 e7.8 ell 18 e8.6 e9.0 19 e9.4 e9.0 20 e9.2 elO 21 e9.2 el7 22 e8.2 e20 23 e8.4 e45 24 e7.6 e88 25 e7.8 e23 26 e8.4 el9 27 e7.8 el4 28 elO el2 29 e25 el7 30 e27 el3 31 e!3 TOTAL 498.0 646.6 MBAN 16.1 21.6 MAX 97 88 MIN 7.6 8.6 AC-FT 988 1280 CFSM .29 .39 IN. .34 .44 e Estimated ell el3 e!6 e22 e24 e20 e!8 elB e21 e!8 elS e!6 e!4 el9 e!3 e!2 elO e9.6 e9.0 e46 e31 e!7 •14 e!2 ell e!2 e!7 e!3 ell elO e9.8 502.4 16.2 46 9.0 997 .30 .34 STATISTICS OF MONTHLY MBAN DATA MBAN 212 184 MAX 2164 831 (WY) 1971 1978 MIN 7.82 12.1 (WY) 1969 1982 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MBAN HIGHEST ANNUAL MBAN LOWEST ANNUAL MBAN HIGHEST DAILY MBAN LOWEST DAILY MBAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 102 565 1971 9.16 1990 FOR e9.8 e9.8 e9.4 e28 eSOOO e5230 e!740 e49 e47 e66 e36 e29 e66 e36 e29 e230 ellO e56 e38 e3l e28 e27 e26 e24 e24 e23 e21 e!9 e!8 e!6 elS 16091.0 519 8000 9.4 31920 9.47 10.92 FOR WATER 66.8 519 1992 7.78 1990 e!4 elS e4S e49 e27 e26 e23 elB el7 e20 e!9 e25 e!6 elS elS e!4 e!3 e!4 e!4 e!4 elS e!4 e!3 e!3 e!3 el4 e!3 e!2 ell 531 18.3 49 11 1050 .33 .36 YEARS 1960 46.6 195 1989 7.65 1990 e9.3 e9.4 e9.0 ell el2 e9.5 e9.2 e45 elS ell e9.8 e9.2 e9.0 e8.8 e8.5 e8.4 e24 elS el2 elO e9.6 e!9 ell e9.6 e9.2 e8.6 e300 e530 e28 e!3 e34 1227 . 1 39.6 530 8.4 2430 .72 .83 - 1992 34.7 120 1972 4.72 1977 1991 CALENDAR YEAR 8590. 23. 900 3. 3. 17040 . 5. 45 11 5. 2 5 Jul 16 1 Aug 14 9 Aug 8 43 83 4 e!9 e600 e40 e!8 e!4 e!7 e21 e!7 elS e!4 e!4 e!3 e!3 el3 e!2 e!3 e!3 e!3 e!3 e!3 e!2 e!2 ell ell ell ell elO e28 e60 e46 1117 37.2 600 10 2220 .68 .76 elSO e!85 e31 e21 e!9 e34 e!8 e20 e!3 • 13 •12 •12 • 13 •13 •31 •74 •22 •120 •180 •74 •170 •78 •400 •280 e!30 •120 elOO •56 •40 •31 •27 2487 80.2 400 12 4930 1.46 1.69 •25 •23 •22 e21 •19 •19 •20 •21 •21 •20 •19 •17 •15 •14 •14 •14 •13 •13 •12 •13 •16 •12 ell elO elO e9.8 •9.8 •9.6 •9.4 •9.4 462.0 15.4 25 9.4 916 .28 .31 •9.2 •9.2 •8.8 •8.6 •9.2 e8.6 •14 •31 •16 ell elO ell •16 •23 •25 •13 ell elO •16 •9.6 •8.8 •12 •23 •34 ell •9.7 •9.4 •9.4 e9.0 •8.6 •8.7 413.8 13.3 34 8.6 821 .24 .28 •9.2 e9.4 •22 elOO •220 e50 •22 •19 •25 •20 •17 •20 •16 •56 •21 •17 •15 •15 el 6 •16 •14 el3 •12 ell •12 •13 ell elO •9.8 elO ell 832.4 26.9 220 9.2 1650 .49 .57 •9.6 ell •19 •28 •16 elS el2 •9.5 •8.7 •8.3 •8.1 •7.5 •7.1 •7.1 •7.3 •15 •26 •45 •97 •45 •20 •15 •12 ell •9.9 •8.8 •8.2 •8.4 •9.4 elO 514.9 17.2 97 7.1 1020 .31 .35 , BY WATER YEAR (WY) 50.7 323 1971 6.61 1977 FOR 1992 25323. 69. 8000 7. 7. 73600 36. 50230 1. 17. 49 14 9. 106 594 1985 6.66 1968 WATER YEAR 2 2 Jan 5 1 Sep 13 7 Sep 9 Jan 5 39 Jan 5 26 19 0 95.3 629 1970 4.93 1977 83.8 489 1961 5.30 1977 WATER 105 368 31 20300 2 3 73600 36 75790 1 25 160 29 8 137 642 1961 9.45 1967 YEARS 1960 .3 Sep .6 Jul .2 Jul Jan .39 Jan .91 .94 .9 157 975 1960 11.9 1967 - 1992 1971 1968 6 1960 25 1974 6 1977 5 1992 5 1992 118 RIO DB LA PLATA BASIN 50043000 RIO DB LA PLATA AT PROYBCTO LA PLATA, PR—Continued WATBR-QOALITY RECORDS PERIOD OF RECORD.--Water years 1958 to current year. WATBR-QOALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 08... DEC 05... FBB 1992 22... APR 20... JDN 10... ADO 07... DATS OCT 1991 08.. . DEC 05.. . FBB 1992 22.. . APR 20... JUN 10... ADG 07... DATS OCT 1991 08.. . DEC 05.. . PEB 1992 22... APR 20.. . JUN 10.. . ADO 07.. . TIME 1200 0930 1100 0905 0950 0925 HARD- NESS TOTAL (MOVL AS CACO3 ) 160 -- -- 80 -- 56 PLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.10 -- __ 0.10 -- 0.10 DIS- CHARGE, INST. CUBIC FEET PER SECOND 24 31 12 300 19 142 CALCIUM DIS- SOLVED (MG/L AS CA) 39 -- -- 20 -- 14 SILICA, DIS- SOLVED (MG/L AS SI02) 24 -- -- 17 -- 17 SPE- CIFIC CON- DUCT- ANCE (US/CM) 437 396 440 395 428 175 MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) 14 -- -- 7.3 -- 5.1 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 257 -- -- 165 -- 109 PH HATER WHOLE FIELD (STAND- ARD UNITS) 8.1 7.7 8.2 7.7 8.3 6.9 SODIUM, DIS- SOLVED (MG/L AS NA) 33 -- -- 15 -- 14 SOLIDS, DIS- SOLVED (TONS PER DAY) 16.4 -- -- 134 -- 41.8 TEMPER- ATURE HATER (DBG C) 27.5 23.5 24.5 25.0 27.5 26.5 SODIUM AD- SORP- TION RATIO 1 -- -- 0.7 -- 0.8 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 23 22 4 291 <1 39 TUR- BID- ITY (NTU) 13 5.0 0.50 280 0.60 26 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 2.8 — -- 3.4 -- 1.7 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 1.87 2.47 -- 1.08 0.690 0.480 OXYGEN, DIS- SOLVED (MG/L) 7.5 6.8 8.3 6.3 8.2 6.2 ALKA- LINITY HAT WH TOT FBT FIELD MG/L AS CACO3 140 130 170 130 150 60 NITRO- GBN> NITRITE TOTAL (MG/L AS N) 0.030 6.130 <*0. 010 0.020 0.010 0.030 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 20 19 <10 36 <10 25 SULPIDE TOTAL (MG/L AS S) <0.5 -- -- <0.5 -- "" NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 1.90 2.60 0.290 1.10 0.700 0.510 COLI- FORM, FECAL, 0.45 UM-MP (COLS./ 100 ML) K650 K600 140 K73000 K80 21000 SULPATB DIS- SOLVED (MG/L AS SO4) 26 -- -- 7.4 -- 8.4 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.050 0.130 0.010 0.020 <0.010 0.070 STREP- TOCOCCI FECAL, (COLS. PBR 100 ML) 520 570 320 65000 K170 3500 CHLO- RIDE, DIS- SOLVED (MG/L AS CL) 34 -- -- 17 — 14 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.45 0.57 0.19 0.58 -- 0.33 K = non- ideal count 119 RIO DB LA PLATA BASIN 50043000 RIO DB LA PLATA AT PROYBCTO LA PLATA, PR—Continued WATER-QUALITY DATA, WATBR YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 08... DBC 05... FBB 1992 22... APR 20... OUN 10... AOG 07... DATE OCT 1991 08... DBC 05... FBB 1992 22... APR 20... JUN 10... AOG 07... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.50 0.70 0.20 0.60 0.20 0.40 IRON, TOTAL RECOV- ERABLE (OG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N) 2.4 3.3 0.49 1.7 0.90 0.91 LEAD, TOTAL RECOV- ERABLE (OQ/L AS PB) NITRO- GEN, TOTAL (MG/L AS NO3) 11 15 2.2 7.5 4.0 4.0 MANGA- NESE, TOTAL RECOV- ERABLE (OG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.710 0.930 0.170 0.360 0.370 0.140 MERCURY TOTAL RECOV- ERABLE (OG/L AS HG) ARSENIC TOTAL (OG/L AS AS) <1 — — <1 -- -- SELE- NIUM, TOTAL (OG/L AS SB) BARIOM, TOTAL RECOV- ERABLE (OG/L AS BA) <100 — " <100 — — SILVER, TOTAL RECOV- ERABLE (OG/L AS AG) BORON, TOTAL RECOV- ERABLE (OG/L AS B) 30 -- -- 30 -- -- ZINC, TOTAL RECOV- ERABLE (OG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (OG/L AS CD) <1 — — <1 — — CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (OG/L AS CR) 2 -- -- 20 — -- PHENOLS TOTAL (OG/L) COPPER, TOTAL RBCOV- BRABLB (OG/L AS CO) <10 — — 30 — — METHY- LENB BLOB ACTIVE SUB- STANCE (MG/L) 920 14000 24 60 430 <0.10 <0.10 40 •cO.010 <0.010 0.07 0.01 720 RIO OB LA PLATA BASIN 50043800 RIO DB LA PLATA AT COMERIO, PR LOCATION.--Lat 18°13'23", long 66°13'30-, Hydrologic Unit 21010005, on right bank 50 ft (15 m) upstream from bridge off Highway 167 in the Town of Comerio, 0.4 mi (0.6 km) southwest of Comerio High School, and 0.2 mi (0.3 km) northeast of Plaza de Comerio. DRAINAGE ARBA.--109 mi* (282 km*). WATER-DISCHARGE RECORDS PERIOD OF RBCORD.—December 1988 to current year. GAGE.--Water-stage recorder and crest-stage gage. Datum of gage is 604.2 ft (184.160 m) above mean sea level. REMARKS.--Records fair except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, HATBR YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JON JUL AUG SEP 1 60 49 2 37 50 3 56 50 4 32 31 5 23 30 6 22 30 7 83 313 8 47 367 9 46 332 10 25 123 11 24 68 12 22 e45 13 19 «35 14 18 «30 15 17 27 16 16 29 17 16 42 18 15 36 19 15 26 20 33 21 21 21 23 22 19 37 23 21 38 24 20 32 25 18 202 26 18 62 27 18 90 28 21 187 29 25 118 30 282 73 31 171 TOTAL 1260 2596 MEAN 40.6 86.5 MAX 282 367 MIN 15 21 AC-FT 2500 5150 CFSM .37 .80 IN. .43 .89 e Estimated STATISTICS OF MONTHLY MEAN MEAN 342 74.0 MAX 866 92.7 (WY) 1991 1991 MIN 40.6 42.6 (WY) 1992 1990 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 46 34 30 36 46 34 28 24 25 22 22 26 20 18 17 17 17 18 17 19 64 49 27 21 19 19 20 20 19 19 19 812 26.2 64 17 1610 .24 .28 DATA 40.2 70.4 1991 23.9 1990 FOR 19 21 21 18 e!4600 e5630 e330 elOO e90 el20 e70 e60 e!20 e70 e60 e400 e250 ellO e85 e70 e60 e55 e50 e45 e42 e38 e35 e33 e31 e29 e28 22690 732 14600 18 45010 6.75 7.78 FOR WATER 221 732 1992 22.8 1990 e27 e27 e80 e90 e50 eSO e40 e35 e34 e37 e36 e45 e30 e29 e28 e25 e24 e25 «25 e25 e26 e27 e25 e25 e24 «27 e25 e24 e23 ___ --- 988 34.1 90 23 1960 .31 .34 YEARS 1989 110 247 1989 24.4 1990 e21 e22 e21 e23 e25 e23 e22 e21 e25 e60 e55 e35 e25 e22 e21 e20 eSO e33 30 25 23 24 24 22 22 22 20 21 21 22 20 820 26.5 60 20 1630 .24 .28 - 1992 48.6 75.7 1989 26.5 1992 1991 CALENDAR YEAR 20781 56. 2500 11 13 41220 . 7. 96 28 16 9 Jul 16 Jul 14 Jun 16 52 12 36 216 35 21 19 18 17 18 29 43 21 18 27 27 23 43 55 25 127 213 60 30 23 19 18 17 16 16 16 17 --- 1263 42.1 216 16 2510 .39 .43 17 30 30 20 17 17 22 20 17 16 14 14 15 15 37 33 52 29 20 31 79 29 832 1930 432 3380 463 184 132 109 106 8142 263 3380 14 16150 2.42 2.79 96 ellS e63 51 49 43 39 42 44 57 128 161 167 224 113 85 71 75 55 48 96 116 72 54 45 40 37 34 34 34 2288 76.3 224 34 4540 .70 .78 30 28 27 26 25 25 25 25 25 27 27 27 29 28 23 22 25 36 30 25 26 26 49 33 28 25 26 22 22 27 28 847 27.3 49 22 1680 .25 .29 29 32 35 36 55 424 163 108 84 75 69 73 69 61 62 63 60 54 51 47 46 45 41 40 40 40 45 46 43 41 40 2117 68.3 424 29 4200 .63 .73 37 37 36 38 39 44 38 35 37 46 37 34 33 33 33 33 45 63 63 642 562 152 91 64 52 47 44 41 39 73 --- 2568 85.6 642 33 5090 .79 .88 , BY WATER YEAR (WY) 32.4 42.1 1992 22.3 1991 FOR 1992 46391 127 14600 14 16 127000 29 14 92020 1 15 115 33 19 92.0 263 1992 25.3 1989 WATER YEAR Jan 5 May 11 May 8 Jan 5 . 22 Jan 5 May 10 .17 .91 40.5 76.3 1992 16.0 1991 52.5 119 1991 19.0 1989 WATER 101 131 45 14600 10 11 127000 29 10 73200 12 130 32 16 53.4 76.1 1989 26.5 1991 YEARS 1989 - .0 Jan 5 Jul 17 Jun 25 Jan 5 .22 Jan 5 Aug 28 .93 .65 235 729 1989 51.2 1991 1992 1991 1990 1992 1989 1989 1992 1992 1990 121 RIO DB LA PLATA BASIN 50043800 RIO DB LA PLATA AT COMBRIO, PR- -Continued WATER-QUALITY RECORDS PERIOD OF RECORDS.-- Water years 1989 to current year. IHSTRXmBNTATION.-- OSD-77 and automatic sediment sampler. REMARKS.—Sediment samples were collected by a local observer on a week basis and during high flow events. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: October 1989 to September 1992 EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATIONi Maximum daily mean, 8,800 mg/L Jan. 05, 1992; Minimum daily mean, 2 mg/L few days. SEDIMENT LOADS: Maximum daily mean, 950,000 tons (862,000 tonnes) Jan. 05, 1992; Minimum daily mean, 0.06 ton (0.05 tonne) Aug 20, 1990. EXTREMES FOR HATER YEARS 1992.— SEDIMENT CONCENTRATION: Maximun daily mean, 8,800 mg/1 Jan. 05, 1992; Minimun daily mean, 2 mg/L Feb. 23, 1992. SEDIMENT LOADS: Maximun daily mean, 950,000 tons (862,000 tonnes) Jan. 05, 1992; Minimun daily mean .23 tons (.21 tonnes) May 12, 1992. SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN MEAN MEAN CONCBN- SEDIMENT MEAN COHCBH- SEDIMENT MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATIOH DISCHARGE DISCHARGE TRATIOH DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) (CPS) (MG/L) (TONS/DAY) (CFS) (MG/L) (TONS/DAY) OCTOBER 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 60 37 56 32 23 22 83 47 46 25 24 22 19 18 17 16 16 15 15 33 21 19 21 20 18 18 18 21 25 282 171 42 28 38 21 17 15 48 35 35 29 24 20 20 21 22 21 19 18 18 27 27 25 22 20 17 13 9 14 19 127 173 7.1 3.0 6.2 1.8 1.1 .94 25 5.4 4.6 2.1 1.5 1.2 1.0 .99 .98 .91 .79 .72 .72 2.6 1.6 1.3 1.2 1.1 .82 .60 .43 1.0 1.4 384 100 NOVEMBER 49 50 50 31 30 30 313 367 332 123 68 e45 e35 c30 27 29 42 36 26 21 23 37 38 32 202 62 90 187 118 73 ___ 89 40 30 29 26 23 148 184 171 40 15 el4 e!2 e!2 12 12 22 17 15 15 16 27 28 24 113 45 54 58 23 19 12 5.5 3.9 2.5 2.2 1.9 278 209 158 17 2.8 1.6 1.0 .91 .86 .88 3.0 1.7 1.0 .90 1.1 2.8 2.9 1.8 76 8.4 23 35 7.8 3.9 ___ DECEMBER 46 34 30 36 46 34 28 24 25 22 22 26 20 18 17 17 17 18 17 19 64 49 27 21 19 19 20 20 19 19 19 17 18 20 19 17 14 12 12 12 12 12 16 20 20 20 20 20 17 14 15 41 17 18 26 33 35 34 32 33 35 35 2.1 1.6 1.7 1.8 1.9 1.3 .92 .81 .78 .73 .75 1.0 1.1 .95 .92 .92 .95 .83 .64 .81 7.3 2.7 1.3 1.4 1.7 1.8 1.8 1.7 1.7 1.8 1.8 TOTAL 1260 562.10 2596 867.35 812 47.51 e Estimated 122 RIO OB LA PLATA BASIN 50043800 RIO OB LA PLATA AT COMBRIO, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CFS) 19 21 21 18 •14600 •5630 •330 • 100 •90 • 120 •70 •60 • 120 •70 •60 •400 •250 • 110 •85 •70 •60 •55 •50 •45 •42 •38 •35 •33 •31 •29 •28 MEAN CONCEN- TRATION (MG/L) JANUARY 28 20 20 20 8800 3560 921 153 22 15 12 11 10 7 8 16 27 31 25 20 11 8 5 3 3 3 3 3 3 5 7 SEDIMENT DISCHARGE (TONS/DAY) 1.4 1.1 1.2 1.0 •950000 •86600 •1190 •41 •5.4 •4.9 •2.2 • 1.8 •3.2 • 1.4 • 1.3 •17 •18 • 9.1 • 5.6 •3.8 • 1.8 • 1.3 .74 .42 .34 .30 .28 .26 .30 .39 .53 FEBRUARY •27 e27 e80 e90 eSO eSO e40 •35 e34 e37 •36 •45 •30 •29 •28 •25 •24 •25 •25 •25 •26 •27 •25 •25 •24 •27 •25 •24 •23 8 8 8 11 23 40 51 50 44 37 30 21 15 19 33 40 36 26 16 10 6 5 2 3 6 8 11 12 12 e.58 e.58 •1.7 •2.6 •3.0 •5.4 •5.5 •4.7 •4.0 •3.7 •2.9 •2.5 •1.2 •1.5 •2.5 •2.7 •2.3 •1.7 •1.0 e.64 .46 .36 .17 .24 .39 .62 .75 .78 .74 MEAN DISCHARGE (CFS) •21 •22 •21 •23 •25 •23 •22 •21 •25 •60 •55 •35 •25 •22 •21 •20 •50 •33 30 25 23 24 24 22 22 22 20 21 21 22 20 MEAN CONCEN- TRATION (MG/L) MARCH 14 15 21 43 73 90 492 48 28 351 355 29 28 27 26 24 23 17 8 8 10 11 11 11 10 8 29 143 170 185 113 SEDIMENT DISCHARGE (TONS/ DAY) • .77 • .90 • 1.2 •2.6 •4.9 •5.6 •29 •2.7 • 1.8 •57 •62 •2.7 • 1.9 • 1.6 • 1.5 • 1.3 •3.1 • 1.4 .67 .57 .63 .71 .70 .67 .60 .46 1.6 9.0 9.4 11 6.4 TOTAL 22690 —— 1037916.06 988 55.21 820 224.38 e Estimated 123 RIO DB LA PLATA BASIN 50043800 RIO DB LA PLATA AT COMBRIO, PR--Continued SEDIMENT DISCHARGB, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SBPTBMBBR 1992 MEAN MEAN CONCEN- SEDIMENT DISCHARGB TRATION DISCHARGB DAY (CFS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 36 216 35 21 19 18 17 18 29 43 21 18 27 27 23 43 55 25 127 213 60 30 23 19 18 17 16 16 16 17 _-_ APRIL 33 121 73 49 39 34 30 53 62 101 192 133 132 155 155 133 194 333 421 429 296 98 25 18 25 29 23 17 25 28 ___ 7.1 179 7.6 3.0 2.0 1.7 1.4 2.5 4.6 10 11 6.1 9.8 11 10 15 27 21 146 258 55 8.9 1.5 .87 1.2 1.4 1.0 .69 1.0 1.3 _._ MEAN DISCHARGB (CFS) 17 30 30 20 17 17 22 20 17 16 14 14 15 15 37 33 52 29 20 31 79 29 832 1930 432 3380 463 184 132 109 106 MEAN CONCBN- SEDIMENT TRATION DISCHARGB (MG/L) (TONS/DAY) MAY 35 18 13 15 8 5 8 13 27 18 9 6 6 8 17 26 64 126 63 43 264 111 504 884 95 1350 198 47 10 9 9 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) JUNE 1.6 1.1 .94 .80 .35 .25 .51 .64 1.1 .77 .32 .23 .25 .31 2.0 2.6 15 9.9 3.2 4.3 107 10 4940 7600 128 27000 276 27 3.7 2.7 2.5 96 el!5 e63 51 49 43 39 42 44 57 128 161 167 224 113 85 71 75 55 48 96 116 72 54 45 40 37 34 34 34 14 24 30 25 20 21 23 23 22 33 82 94 81 127 74 57 48 42 38 33 49 28 53 79 56 22 16 13 13 13 3.8 «7.5 «5.3 3.4 2.8 2.6 2.4 2.6 2.6 7.4 31 50 39 88 25 14 9.3 8.9 5.7 4.2 19 8.7 10 11 7.0 2.3 1.6 1.2 1.2 1.1 TOTAL 1263 806.66 8142 40143.07 2288 378.6 e Estimated 124 RIO DB LA PLATA BASIN 50043800 RIO DB LA PLATA AT COMERIO, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCEN- DISCHARGB THAT ION DAY (CPS) (MG/L) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL YEAR 30 28 27 26 25 25 25 25 25 27 27 27 29 28 23 22 25 36 30 25 26 26 49 33 28 25 26 22 22 27 28 847 46391 JULY 14 15 16 19 24 29 32 31 24 20 16 17 19 30 33 16 7 8 9 10 8 7 33 20 10 7 9 10 10 10 10 ... SEDIMENT DISCHARGE (TONS/DAY) MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) AUGUST 1.1 1.1 1.2 1.3 1.6 2.0 2.2 2.1 1.7 1.5 1.2 1.3 1.4 2.2 2.1 .93 .48 .77 .73 .66 .55 .50 4.6 1.8 .70 .53 .60 .60 .58 .68 .76 39.47 1083424.55 29 32 35 36 55 424 163 108 84 75 69 73 69 61 62 63 60 54 51 47 46 45 41 40 40 40 45 46 43 41 40 2117 10 10 11 11 32 204 81 30 19 17 14 13 12 11 11 12 12 12 15 19 20 20 19 16 12 9 8 9 66 14 17 —— .77 .86 .99 1.1 6.5 332 41 9.1 4.3 3.3 2.6 2.4 2.2 1.8 1.9 2.0 1.9 1.7 2.0 2.4 2.5 2.3 2.1 1.7 1.2 .96 .96 1.1 7.7 1.6 1.8 444.74 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) SEPTEMBER 37 37 36 38 39 44 38 35 37 46 37 34 33 33 33 33 45 63 63 642 562 152 91 64 52 47 44 41 39 73 2568 19 21 22 24 25 25 23 21 18 15 14 14 13 13 13 13 31 44 46 193 244 90 50 39 36 33 32 30 28 47 --- —— 1.9 2.1 2.1 2.4 2.6 2.9 2.3 2.0 1.9 1.7 1.4 1.3 1.2 1.2 1.2 1.2 4.4 7.6 9.2 1360 434 43 13 6.8 5.0 4.1 3.7 3.3 2.9 13--- 1939.4 125 RIO DB LA PLATA BASIN 50043800 RIO DB LA PLATA AT COMBRIO, PR—Continued HATER QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT DATE JAN 1992 05... 05... APR 10... MAY 24... 26... DATE JAN 1992 05... 05... APR 10... MAY 24... 26... TIME 1745 1630 1630 0010 0618 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .016 MM 51 64 -- -- 36 DIS- CHARGE, INST. CUBIC FEET PER SECOND 11300 6960 29 4950 10780 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM 63 76 -- 71 44 SEDI- MENT, SUS- PENDED (MG/L) 10700 23100 582 2680 6000 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 77 90 98 92 59 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 327000 434000 46 35800 175000 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 93 96 98 98 73 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM 22 15 69 37 23 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 97 99.8 98 99 85 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM 32 25 77 39 27 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 99 99. 100 100 97 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 41 43 81 49 29 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 99.9 8 99.9 100 100 99 126 RIO DB LA PLATA BASIN 50043800 RIO DB LA PLATA AT COMERIO—Continued WATER QUALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT DATE OCT 1991 03.. . 31... JAN 1992 05... 06... APR 02... 13... MAY 23... 24... 26... JUN 09... JUL 03... AUG 06... SBP 20... TIME 1733 1905 1550 2200 2006 0800 2020 0050 0710 1452 1730 1030 2115 STREAM- PLOW, INSTAN- TANEOUS (CFS) 50 74 1700 2460 18 18 4310 4590 8720 39 27 719 570 SEDI- MENT, SUS- PENDED (MG/L) 49 693 70100 762 545 402 3530 2280 2080 153 327 1280 570 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 6.7 138 320000 5060 26 19 41000 28200 48990 16 24 2480 877 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 91 99 35 98 98 98 88 95 99 96 97 97 98 127 RIO DB LA PLATA BASIN 50044000 RIO DB LA PLATA NEAR COMERIO, PR WATER-QUALITY RECORDS LOCATION.--Lat 18?14'33", long 66?12'28", at bridge on Highway 156, 0.56 mi (0.9 km) upstream from dam, about 2.0 mi (3.2 km) northeast of Comer Io plaza. DRAINAGE ARBA.--139 mi' (360 km'), excludes 8.2 mi' (21.1 km') upstream from Carite Reservoir, the flow of which is diverted to Rio Guamanl. PERIOD OF RECORD.--Hater years 1979 to current year. DATE OCT 1991 15. .. DEC 10.. . FBB 1992 24... APR 01. . . JUN 08. .. AUG 05. .. TIME 1200 1300 1515 1010 0950 1005 DIS- CHARGE, INST. CUBIC FEET PER SECOND 26 35 37 27 55 68 SPE- CIFIC CON- DUCT- ANCE (US/CM) 427 425 420 431 389 372 PH WATER WHOLE FIELD (STAND- ARD ONITS) 8.5 8.3 7.8 8.0 8.7 8.1 TEMPER- ATURE WATER (DBG C) 27.0 24.5 25.0 26.0 27.0 27.0 TUR- BID- ITY (NTU) 6.1 2.5 1.3 1.1 0.90 1.6 OXYGEN, DIS- SOLVED (MG/L) 10.0 9.2 8.1 8.8 9.5 7.4 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 120 110 98 108 102 91 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 14 19 17 14 12 16 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 540 K92 240 K850 K650 2800 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) K100 K150 310 K200 K100 2600 DATE OCT 1991 15... DEC 10.. . FBB 1992 24.. . APR 01. . . JUN 08. . . AUG 05... HARD- NESS TOTAL (MG/L AS CALCIUM DIS- SOLVED (MG/L MAGNE- SIUM, DIS- SOLVED (MG/L SODIUM, DIS- SOLVED (MG/L SODIUM AD- SORP- TION RATIO POTAS- SIUM, DIS- SOLVED (MG/L ALKA- LINITY WAT WH TOT PET FIELD MG/L AS SULFIDB TOTAL (MG/L SULFATB DIS- SOLVED (MG/L CHLO- RIDE, DIS- SOLVED (MG/L CACO3) AS CA) AS MG) AS NA) 150 36 160 39 130 32 15 26 16 28 13 26 AS K) 0.9 3.0 4.7 2.6 CACO3 540 140 160 170 130 120 AS S) AS S04) AS CL) <0.5 22 <0.5 21 20 30 37 30 OCT 15 DEC 10 FBB 24 APR 01 JUN 08 AUG 05 K * FLUO- RIDB, DIS- SOLVED DATE (MG/L AS F) 1991 0.10 1992 0.20 0.10 non- ideal count SILICA, DIS- SOLVED (MG/L AS SIO2) 29 -- -- 20 -- 24 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 485 -- -- 268 -- 229 SOLIDS, DIS- SOLVED (TONS PER DAY) 34.4 -- T- 19.5 -- 42 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 8 35 -- 2 1 22 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.660 0.870 0.360 -- -- -- NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.010 0.010 0.010 <0.010 <0.010 <0.010 NITRO- GEN, N02+N03 TOTAL (MG/L AS N) 0.670 0.880 0.370 0.260 0.290 0.200 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.040 0.020 0.040 0.020 0.010 0.040 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.26 0.28 0.26 -- 0.19 0.36 128 RIO DB LA PLATA BASIN 50044000 RIO DB LA PLATA NEAR COMBRIO, PR—Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 15... DEC 10... FBB 1992 24... APR 01... JUN 08... AUG 05.. . DATE OCT 1991 15... DEC 10... FBB 1992 24... APR 01... JUN 08... AUG 05... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.30 0.30 0.30 <0.20 0.20 0.40 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) 0.97 1.2 0.67 — 0.49 0.60 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N03) 4.3 5.2 3.0 -- 2.2 2.7 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.370 0.370 0.210 0.110 0.140 0.290 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) ARSENIC TOTAL (UG/L AS AS) <1 -- -- 1 -- -- SELE- NIUM, TOTAL (UG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 — -- <100 -- -- SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) 90 -- -- 60 -- -- ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 -- -- <1 -- -- CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) <1 -- -- <1 -- -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) <10 — — 20 — -- MBTHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 440 170 40 30 <0.10 <0.10 <0.010 <0.010 0.04 0.03 Z •« d H > B O UIUIMMMM MMMMM M H> H> H> H> M H> H> H> H> H> • • n i Z M > 4 H> e vo <e «J o> vi » u M H> otooo^Jo. in » ui M H> o M *. K vo in n tO • VO CO h« to vi to •• O M H> H> -J 0t "t H> <O h* H> H> B to • to •• o P to W to • • K M Mh* H> <O M VI h» h> H O to > to vo 10 >• to ot vo * * 4 rr vi »«4 • M vi« ...... ..... ..... ..... ... . ..... • -J tO »J O\ to H »J » M 0t 0t 0t VO Ot ON VO CO h* h* M VO 0t O eOOUIVI <OM<O 0t -J 00 to VO Ul 0k vi e co H> M to H> 0t «•) 00 * 0\ O VI 00 <O -JMVOM H> * <O M » I 0t «4 0> <O VI » Ul O O i» 10 »<o oui oo n S i if » 8 7 R OHO & 3 II rr rr 5-rr & g 9 O H> Q>0a H> VO II 00 10 •» B • rr e P- to oo - _ 0 • •W H -»H 0 •>» B e to M h* && vi vi e w vi H> K H> M H> WM to Ul Ul 1C . vO • « h> tO M -1 Ul H> h> H> H> h> VOK VO VIM M to* VO • . >! H> 0t Mfc VI tf i to M O W <-s 3 H VI H VI OT VI » M *• H I • > ON u vi M o in in ON ON «J oo 0* co ve ve < U 0t M * Ul • • ...... .... ». ut o 10 ON in o\ inoiinvoioui w vi M vi ui vi M K> H » •> W UI0t<OUlM OA Ul Ul Ul Ul C| M M *• *• Z 3 5 I 8 I B I Ol CO 10 O UlxlOllOUl -00000010 M VI <O to «4 l0Hin»«t Ul H> H> IB ».ie*> • • ..... ..... ..... .. »ie<o<ovi o> e u> fc oo o> u> «4»uwvp o K K tj 1/1 cow •• •• MM _ fc *. fc fc *i VI0t0t<OVI »<OM<O0t > ui 01 >J co to o oK ui o 0>M fc y> o w M vi w M M vi e vi <o e ON in <o »J o. *• > in oi M ON CD vi oi in ot to ^ o> vi i in in vi o> o. ON -J -J oo to S. B * J a rr I f a9 M <a ' 8 ^ MieO ° 58 5 • H 9D H ':& °: 58 P-0 Q 00 5^0 I p ON VO in M K VI ON I UIIO » «k *i VI -J to K Ol M Ul VI CO M to • to fc > VO VI to . M MH> H> 0 VI •MM *vp LJLJLJLJW W t»«4.h*VI. ...... to «J vo M H> «•) e e w w u vi otininiOK oo o fc in in to M ee MWMMM is . . wi ui . to w w u u «fc H O <O > «J W « ..... «J M * H> «> >•» M « » fc * fc vi vi vi vi vi 01 «4 e vi <o 0t «4 co 0i vo e MVOUIUIUI >• «4M0t OMUIONO 0|MM»«4 to -J Ul O 0t «J «4 *• Ul Ul H> Q H«H e u i vi vi eu in to «e vo vo to to vo vo vo to to to vo vo MM M M M MH VI «4 M Ul ' * Ulk> • 0) I WMMMM WW*»W «0 Ul W VO M MMMMM W Ul W VI VI •4 01 *• • UI«D- I . . . . . ..... ... ..... ..... I H> «4 VI VI W H>MH»JUl » A> Ol VI VI in CO VO O M ON M Ul i e fc ui ui n > vi w» " 10 <0 130 RIO DB LA PLATA BASIN 50044830 RIO GUADIANA AT GUADIANA, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORDS.-- Water years 1990 to current year. INSTRUMENTATION.-- USD-77 and automatic sediment sampler. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: August 01, 1990 to September 1992 i EXTREMES FOR PERIOD OF DAILY RECORD.— SEDIMENT CONCENTRATIONi Maximum daily mean, 1,300 mg/L Oct. 16, 1990; Minimum daily mean, 2 mg/L few days. SEDIMENT LOADSt Maximum daily mean, 18,000tons (16,300tonnes) Jan. 05, 1992; Minimum daily mean, 0.00 ton (0.0 tonne) several days. EXTREMES FOR WATER YEARS 1990-92.-- Water Year 1990 1991 1992 Suspended-sediment concentration (mg/L) meximum minimum 259 (Sep. 25) 1,430 (Feb. 05) 2,690 (Jan. 05) Suspended-sediment discharge (tons per day) maximum minimum 2 (Aug. 20) 1 (Several days) 2 (Several days) 185 (Sep. 03) 8.650 (Feb. 05) 18,000 (Jan. 05) .05 (Aug. 04) .00 (Several days) .02 (Several days) SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1989 TO SEPTEMBER 1990 DAY MEAN DISCHARGE (CFS) MEAN CONCEN- TRATION (MG/L) JULY SEDIMENT DISCHARGE (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN DISCHARGE (CFS) e4.1 e5.8 e5.4 e4.3 eS.O e6.8 e8.8 e6.2 e6.0 e8.2 e6.4 e7.0 elO 9.0 6.0 5.1 4.6 4.6 4.2 4.2 4.0 5.8 4.9 4.3 6.2 4.5 4.1 24 14 5.5 4.8 203.8 MEAN CONCEN- TRATION (MG/L) AUGUST 6 9 6 5 5 9 13 9 9 12 7 10 17 15 9 6 6 6 6 5 5 7 7 6 11 6 5 69 74 20 8 SEDIMENT DISCHARGE (TONS/DAY) .06 .18 .08 .05 .08 .16 .30 .16 .14 .26 .12 .18 .46 .36 .14 .08 .08 .07 .06 .06 .06 .12 .10 .07 .30 .07 .06 30 3.6 .31 .10 37.87 MEAN DISCHARGE (CFS) 6.6 5.7 66 22 38 15 59 28 13 9.8 13 8.4 7.3 30 14 8.6 7.2 13 8.4 7.0 6.5 6.7 14 7.9 23 11 9.2 8.2 8.5 8.5 MEAN CONCEN- TRATION (MG/L) SEPTEMBER 11 8 231 50 115 31 188 62 28 17 26 14 10 72 25 14 10 27 15 10 10 10 27 13 63 21 17 15 12 14 483.5 SEDIMENT DISCHARGE (TONS/DAY) .31 .15 185 5.3 49 1.7 114 6.1 1.0 .47 2.0 .34 .20 17 1.0 .33 .17 2.8 .38 .16 .16 .16 2.0 .29 25 .77 .56 .34 .27 .41 417.37 e Estimated 131 RIO DE LA PLATA BASIN 50044830 RIO GUADIANA AT GUADIANA, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN DISCHARGE DAY (CPS) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 7.9 5.7 15 56 33 19 108 46 194 186 68 30 20 146 234 225 208 306 281 102 322 81 44 38 73 87 40 27 22 19 17 MEAN MEAN CONCEN- SEDIMENT MEAN CONCBN- SEDIMENT TRATION DISCHARGE DISCHARGE TRATION DISCHARGE (MG/L) (TONS/DAY) (CPS) (MG/L) (TONS/DAY) OCTOBER 13 8 62 156 75 36 430 94 790 699 211 68 38 593 955 900 828 1250 1160 218 1090 59 35 42 265 255 65 20 8 6 6 NOVEMBER .31 .12 3.7 38 7.7 1.9 599 16 2080 906 47 6.3 2.1 1100 2750 2070 1490 3370 2060 88 1430 15 4.2 7.4 245 114 8.3 1.6 .49 .32 .29 16 15 15 16 15 14 13 13 13 12 12 12 11 11 10 13 11 11 11 12 12 27 14 11 10 11 14 11 33 25 5 4 4 4 4 4 5 4 3 3 3 4 4 4 4 5 5 5 5 12 23 56 16 8 7 7 20 8 93 56 —— .24 .18 .16 .17 .17 .17 .18 .14 .10 .10 .11 .12 .12 .11 .12 .17 .15 .14 .15 .53 .80 5.4 .61 .26 .19 .19 .93 .26 46 4.9 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) DECEMBER 25 38 105 40 21 16 14 13 12 12 12 14 11 11 11 10 9.5 9.4 9.3 9.3 9.3 11 13 13 9.9 9.2 9.2 10 18 42 66 55 98 281 22 11 7 5 4 4 4 4 6 8 10 10 9 8 7 5 3 3 5 6 6 7 6 5 5 39 116 157 4.3 19 147 2.8 .70 .30 .20 .15 .12 .12 .14 .20 .27 .28 .28 .24 .22 .17 .12 .09 .08 .14 .21 .22 .19 .15 .12 .13 5.6 28 41 TOTAL 3060.6 18462.73 424 62.87 613.1 252.54 132 RIO DB LA PLATA BASIN 50044830 RIO GUADIANA AT GOADIANA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN MEAN CONCEN- SEDIMENT DISCHARGE THAT ION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) JANUARY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 58 29 19 15 21 25 21 18 19 20 18 16 14 13 12 12 11 11 11 10 9. 9. 9. 8. 8. 8. 8. 7. 7. 7. 10 7 2 5 9 9 9 6 9 9 9 158 36 20 20 42 55 41 22 15 15 12 7 5 6 10 12 9 4 4 4 5 5 7 12 16 16 13 8 7 9 10 28 3.1 1.0 .81 4.8 3.7 2.4 1.0 .71 .81 .59 .28 .19 .20 .34 .40 .27 .13 .11 .11 .12 .12 .18 .29 .37 .38 .29 .18 .15 .18 .29 MEAN DISCHARGE (CFS) MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) FEBRUARY 9.6 8.5 8.3 23 335 58 23 16 14 15 14 17 18 14 12 13 12 45 59 44 30 20 16 14 12 11 11 14 ___ 12 12 12 60 1430 164 37 15 11 20 24 32 38 22 10 11 22 136 166 127 61 18 9 6 5 5 5 19 ___ —— 18 8650 37 2 1 2 2 58 34 18 6 1 .29 .26 .25 .6 .67 .39 .1 .88 .3 .0 .84 .31 .54 .72 .2 .97 .38 .23 .16 .15 .16 .5 ___ ___ MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MARCH 11 11 10 12 10 11 11 10 9.5 9.1 10 8.8 9.2 8.9 8.1 7.3 7.2 10 7.6 7.0 8.1 101 24 12 9.7 11 12 9.3 8.3 7.9 7.6 13 6 5 4 5 4 2 3 5 5 7 7 7 5 3 3 3 14 4 4 6 346 47 6 6 13 11 5 4 4 2 .39 .18 .14 .12 .13 .11 .05 .09 .12 .13 .17 .18 .17 .11 .07 .06 .07 .43 .10 .08 .14 158 4.4 .22 .17 .64 .42 .14 .09 .09 .05 TOTAL 470.4 51.50 886.4 8837.90 399.6 167.26 133 RIO DB LA PLATA BASIN 50044830 RIO GOADIANA AT GUADIANA, PR--Continued SBDIHENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN MEAN COHCEN- SBDIHENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL 7.6 8.7 7.5 7.1 7.1 7.0 9.1 21 11 8.9 10 16 24 19 56 18 12 11 9.6 8.6 8.0 7.7 7.4 6.9 6.7 6.5 6.4 6.3 5.8 5.8 --- 346.7 APRIL 4 7 6 5 5 5 14 21 15 15 16 35 57 47 379 38 21 17 14 12 11 7 5 5 6 7 8 7 7 8 --- ___ MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MAY .08 .16 .11 .09 .10 .09 .42 1.3 .47 .36 .41 3.7 7.1 4.5 292 2.1 .68 .48 .34 .26 .22 .15 .10 .09 .10 .13 .13 .13 .11 .12 --- 316.03 5.8 7.2 7.1 6.0 5.9 5.9 7.6 19 9.5 7.1 7.6 11 11 9.7 7.1 6.1 5.7 6.8 9.5 7.6 5.8 5.1 4.8 4.8 18 5.9 4.9 4.5 4.3 5.7 5.2 232.2 9 13 9 6 6 6 10 43 72 8 9 12 15 16 14 IS 15 14 23 17 16 16 11 8 40 8 6 5 S 9 7 .14 .28 .19 .11 .10 .10 .28 4.6 2.6 .14 .28 .47 .88 .45 .25 .23 .22 .25 .68 .36 .25 .21 .15 .11 5.4 .13 .09 .07 .06 .26 .10 19.44 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) JUNE S.I 3.9 3.6 3.6 3.S 3.8 3.7 3.3 3.1 3.0 3.0 3.0 2.8 2.8 2.8 2.7 2.7 3.0 3.3 3.2 3.1 3.1 29 4.4 3.3 2.8 2.6 2.6 7.5 32 --- 156.3 8 8 8 7 7 8 10 7 4 4 4 3 3 4 6 10 11 13 15 IS 12 7 389 17 17 19 20 15 16 94 --- ___ .12 .08 .08 .07 .06 .07 .09 .06 .03 .04 .02 .03 .02 .03 .05 .07 .07 .09 .13 .13 .10 .06 184 .21 .16 .15 .14 .11 .90 30 217.17 134 RIO OB LA PLATA BASIN 50044830 RIO GUAOIANA AT GUAOIANA, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL YEAR 6.4 3.7 4.6 4.0 3.3 3.0 7.4 4.4 3.2 2.9 3.0 2.9 2.9 2.7 27 250 22 9.0 6.5 5.3 .7 .4 .1 .3 .9 .0 .2 .5 .0 .2 17 433.5 7320.0 JULY 16 12 10 13 13 15 20 10 11 11 9 9 8 8 78 1010 55 15 12 12 10 8 5 5 5 5 5 5 5 5 51 —— MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AUGUST .31 .12 .13 .13 .11 .11 .57 .12 .09 .08 .08 .08 .07 .06 19 2010 4.5 .40 .24 .16 .12 .09 .05 .05 .06 .86 .05 .06 .05 .05 19 2056.00 30547.92 7.1 5.1 4.4 4.1 4.0 3.8 3.8 4.1 3.7 3.5 3.5 3.6 3.7 e3.6 e3.4 e3.9 4.6 4.0 3.2 3.7 3.5 41 9.6 5.1 4.4 4.1 11 6.7 4.6 4.0 3.9 178.7 11 5 5 4 3 2 1 1 1 1 1 1 1 1 1 1 1 1 1 17 20 147 79 10 1 1 21 9 3 2 2 ... .27 .06 .06 .05 .03 .02 .01 .01 .01 .00 .00 .00 .00 e.Ol e.OO e.Ol .01 .01 .00 .24 .19 92 2.4 .15 .02 .01 1.2 .19 .04 .02 .01 97.03 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) SEPTEMBER 3.5 3.6 3.2 3.0 3.1 3.1 3.5 3.1 3.0 3.0 2.8 6.9 3.7 2.9 2.7 3.3 6.8 4.0 3.3 3.3 3.3 4.8 5.2 3.9 3.4 3.3 3.3 3.2 4.3 12 118.5 2 3 2 1 1 1 1 1 1 1 2 12 7 5 4 3 11 4 3 2 2 2 2 2 2 2 4 12 15 34 .02 .02 .01 .00 .00 .00 .01 .00 .00 .00 .01 .79 .08 .05 .03 .03 .28 .04 .02 .02 .02 .02 .04 .02 .02 .01 .03 .10 .18 5.6 7.45 135 RIO DB LA PLATA BASIN 50044830 RIO GUADIANA AT GUADIANA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/ DAY) OCTOBER 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 5.3 5.9 3.9 3.8 5.7 3.6 19 8.7 4.2 3.7 3.5 3.3 3.0 3.0 3.0 3.0 2.6 2.9 3.2 3.1 3.1 2.8 2.9 2.6 2.6 2.9 2.6 3.6 8.6 9.2 4.4 12 14 7 8 12 12 79 124 48 104 13 10 10 10 10 10 10 10 10 8 8 9 10 10 15 19 17 11 25 33 12 .20 .25 .09 .09 .19 .11 15 3.5 .54 1.2 .12 .09 .07 .08 .08 .08 .07 .07 .08 .07 .06 .06 .08 .07 .10 .15 .12 .13 2.1 1.2 .14 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) TOTAL 139.7 26.19 17 13 9.8 6.0 e4.5 7.6 11 12 8.4 5.0 3.9 3.8 3.2 3.3 2.9 4.7 4.0 3.1 3.1 3.1 5.9 6.1 13 31 8.0 6.8 5.1 3.9 5.8 4.6 219.6 NOVEMBER 69 104 79 38 22 13 3.7 2.3 .64 e.27 23 21 13 17 14 10 10 10 8 8 8 8 7 8 10 17 14 49 85 14 12 12 11 16 18 .48 .65 .40 .39 .22 .11 .09 .09 .08 .06 .10 .09 .07 .07 .08 .68 .30 5.2 13 .30 .22 .15 .11 .50 .24 43.59 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) DECEMBER 3.8 4.3 5.0 7.7 8.4 7.2 6.4 6.3 7.4 6.3 5.1 5.7 4.8 6.7 4.4 4.2 3.7 3.4 3.1 16 12 6.1 4.9 4.2 3.7 3.7 5.8 4.5 4.0 3.6 3.4 175.8 20 16 11 8 8 8 8 8 8 7 5 5 5 5 5 5 5 5 5 57 30 5 5 5 5 5 5 5 5 5 5 .20 .17 .14 .16 .17 .15 .13 .14 .15 .13 .06 .09 .07 .09 .06 .06 .05 .04 .04 8.6 1.3 .08 .06 .06 .05 .05 .08 .06 .05 .04 .05 12.58 e Estimated 736 RIO DB LA PLATA BASIN 50044830 RIO QDAOIANA AT GUADIANA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CFS) 3.4 3.4 3.2 3.2 536 342 43 17 16 23 13 10 23 13 9.9 81 48 20 14 11 10 9.5 9.2 8.5 8.3 8.3 7.2 6.9 6.5 5.6 5.5 MEAN CONCEN- TRATION (MG/L) JANUARY 5 5 5 5 2690 1800 148 43 59 66 22 22 70 35 24 594 182 42 17 10 10 10 10 10 10 10 10 12 16 20 21 SEDIMENT DISCHARGE (TONS/DAY) .05 .04 .04 .04 18000 2710 21 1.9 3.5 5.3 .75 .58 5.1 1.3 .64 663 33 2.3 .63 .28 .25 .25 .27 .23 .22 .22 .20 .20 .28 .28 .31 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) FEBRUARY MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MARCH 5.1 5.1 15 17 9.3 9.4 8.4 6.5 6.1 6.9 6.7 8.9 5.7 5.5 5.2 5.0 4.6 4.8 4.8 4.7 5.3 5.2 4.6 4.7 4.3 5.0 4.2 3.8 3.6 21 19 47 55 20 6 6 10 9 8 13 15 5 5 5 5 4 4 7 6 4 7 9 10 7 6 7 8 8 .27 .24 7.3 3.3 .55 .14 .13 .18 .14 .14 .32 .50 .07 .06 .06 .07 .04 .05 .10 .08 .06 .09 .11 .11 .08 .09 .08 .08 .08 3.2 3.3 3.1 3.7 4.0 3.3 3.2 16 6.3 3.8 3.5 3.3 3.1 3.1 3.0 2.9 8.3 5.3 4.4 3.7 3.3 6.6 3.8 3.4 3.3 3.0 81 197 17 4.6 12 5 3 3 3 7 28 53 111 88 26 6 2 2 2 3 3 15 8 5 3 2 13 10 9 6 4 416 914 77 9 42 .05 .02 .02 .03 .08 .22 .42 20 1.8 .28 .06 .02 .02 .02 .02 .03 .74 .12 .06 .03 .02 .31 .09 .08 .06 .04 659 4580 5.0 .12 4.8 TOTAL 1318.6 21452.16 185.4 14.52 425.5 5273.56 137 RIO DB LA PLATA BASIN 50044830 RIO GUADIANA AT QUADIANA, PR--Continued SBDIMBNT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCEN- SBDIMBNT DISCHARGE THATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) APRIL 1 6.4 2 217 3 22 4 7.2 5 4.8 6 5.0 7 7.3 8 6.1 9 e6.0 10 eS.O 11 • 12 • 13 14 IS 16 17 18 19 20 21 22 23 .9 .8 .7 .6 .3 .3 .7 .5 .5 .4 .5 .1 .0 24 3.9 25 3.8 26 3.7 27 3.7 28 3.4 29 21 30 16 31 IS 1070 99 26 IS IS IS 14 14 13 11 8 5 4 4 S 5 S 4 3 S S 6 S S 7 8 11 83 91 ___ .28 4200 6.1 .55 .18 .22 .27 .24 • .22 • .17 • .IS e.ll .07 .05 .06 .06 .06 .06 .05 .04 .06 .06 .06 .05 .04 .07 .08 .09 23 6.1 ___ MEAN MEAN CONCEN- SBDIMBNT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) MAY 45 66 IS 8.4 6.5 12 6.8 5.4 .9 .6 .4 .2 .2 .6 .3 26 7.5 29 65 26 60 27 145 130 45 42 42 23 IS 12 9.6 191 109 12 12 12 35 9 6 3 2 2 2 2 2 4 99 19 112 300 79 263 90 SS2 241 125 143 110 110 105 46 6 85 38 .51 .27 .20 1.5 .17 .09 .04 .02 .02 .02 .02 .03 .05 30 .45 23 256 6.8 133 9.0 702 110 16 18 14 6.7 4.3 1.5 .15 TOTAL 400.6 4238.55 900.4 1456.84 MEAN DISCHARGE (CPS) 9.1 8.2 7.8 7.8 6.8 6.4 6.9 7.4 7.1 7.3 6.9 6.0 5.4 5.1 5.0 5.2 4.8 4.5 4.3 4.1 5.6 4.1 3.9 3.7 3.5 3.4 3.4 3.4 3.2 3.3 163.6 MEAN CONCEN- SBDIMBNT THATION DISCHARGE (MG/L) (TONS/DAY) JUNE 2 3 7 10 6 5 5 5 5 5 5 5 6 8 10 11 9 7 6 6 17 8 7 8 12 18 IS 9 6 5 .04 .07 .15 .20 .11 .09 .10 .10 .10 .10 .09 .08 .08 .11 .13 .14 .11 .08 .06 .07 .36 .08 .08 .08 .11 .16 .13 .09 .05 .04 3.19 • Estimated 138 RIO DB LA PLATA BASIN 50044830 RIO QUADIANA AT GUADIANA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CPS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL YEAR 3.2 3.2 3.2 2.9 3.2 3.0 3.0 11 7.2 3.9 3.5 3.5 4.4 7.0 8.8 5.1 4.2 3.5 5.5 3.6 3.0 3.1 5.4 12 3.9 3.5 3.3 3.3 3.3 3.0 3.0 139.7 4534.3 JULY 5 5 6 6 6 6 6 32 17 7 7 7 8 15 22 11 8 7 15 17 11 7 13 34 6 5 4 3 3 3 3 ... MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) MEAN DISCHARGE (CPS) AUGUST 1 .04 .04 .05 .04 .05 .05 .04 1.8 .38 .09 .07 .06 .09 .49 .91 .18 .09 .07 .51 .17 .08 .05 .42 2.6 .06 .04 .03 .02 .03 .03 .03 8.61 33242.90 3.1 3.3 3.3 19 78 30 9.4 6.7 8.7 7.6 6.0 7.3 5.7 20 7.9 6.7 5.4 5.2 5.2 5.6 5.0 .6 .3 .2 .0 .6 .2 3.7 3.4 3.4 3.7 289.2 4 5 6 67 614 522 12 6 18 18 11 14 11 67 16 10 10 9 8 8 7 4 3 3 3 9 5 6 8 8 8 —— .03 .07 .06 11 534 77 .30 .12 .65 .44 .19 .38 .17 14 .42 .17 .13 .12 .11 .13 .09 .06 .04 .04 .04 .16 .05 .06 .07 .07 .08 640.25 3.4 3.3 4.5 10 6.1 5.3 5.2 3.6 3.2 3.0 2.9 2.8 2.5 2.5 2.5 2.6 9.4 3.4 33 29 9.3 4.7 4.1 3.2 3.1 2.8 2.5 2.5 2.7 3.1 — - 176.2 MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) SEPTEMBER 3.4 3.3 4.5 10 6.1 5.3 5.2 3.6 3.2 3.0 2.9 2.8 2.5 2.5 2.5 2.6 9.4 3.4 33 29 9.3 4.7 4.1 3.2 3.1 2.8 2.5 2.5 2.7 3.1 10 10 14 27 14 11 14 8 5 3 3 2 2 3 6 8 31 6 134 126 29 14 14 12 12 10 7 5 5 5 ' .09 .09 .17 1.7 .26 .18 .32 .08 .05 .03 .02 .02 .02 .02 .04 .05 3.6 .07 37 27 1.2 .21 .16 .12 .11 .08 .05 .04 .04 .04 72.86 139 RIO DB LA PLATA BASIN 50044830 RIO GUADIANA AT OOADIANA , PR--Continued WATBR QUALITY DATA, WATER YEARS OCTOBER 1990 TO SEPTEMBER 1992 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT DATE OCT 1990 17... APR 1991 15... JUN 23... JAN 1992 05... 05... 16... MAY 23. .. AUG 05.... DATE OCT 1990 17. .. APR 1991 15... JUN 23... JAN 1992 05. .. 05... 16. .. MAY 23. .. AUG 05. .. TIME 1601 1317 1015 1727 1917 1832 1852 2127 SBD. SUSP. PALL DIAM. PERCENT FINER THAN .016 MM 56 60 74 39 46 55 15 68 DIS- CHARGE, INST. CUBIC FEET PER SECOND 704 403 208 1190 1850 512 578 344 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM 67 68 86 47 53 65 24 78 SEDI- MENT, SUS- PENDED (MG/L) 3370 4940 4920 7370 8200 3840 3030 3860 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 82 86 96 60 66 84 63 95 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 6400 5370 2760 23700 41000 5310 4730 3580 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 91 94 98 72 75 90 51 98 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM 33 26 40 17 21 25 1 35 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 978 96 99 79 84 93 67 99 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM 38 36 52 23 28 36 3 44 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 99.4 97 99.6 87 94 98 83 99.7 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 46 46 61 31 37 41 6 54 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 100 98 100 94 99 99 95 100 740 RIO DB LA PLATA BASIN 50044830 RIO GOADIANA AT GOADIANA, PR--Continued HATER QUALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT DATE OCT 1991 08... NOV 06... DEC 17.. . JAN 1992 05... 05... 16... 16... MAR 31... MAY 21... 23.. . 23.. JUL 08... ADO 05... SEP 17... TIME 1500 1215 1152 1607 1657 1917 2127 1805 1830 1827 2222 1635 2027 1620 STREAM- FLOW, INSTAN- TANEOUS (CFS) 6.4 7.8 3.6 423 562 500 205 45 126 400 342 20 443 11 SEDI- MENT, SUS- PBNDBD (MQ/L) 113 55 23 3500 4250 2560 1140 779 929 2940 1030 91 4540 270 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 2 1.2 0.2 4000 6450 3460 633 95 316 3170 956 5 5430 8 BED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 100 98 96 96 91 89 91 62 94 60 81 94 94 98 141 RIO DB LA PLATA BASIN 50044850 RIO GUADIANA NEAR NARANJITO, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°18'39", long 66°13'28', at steel-cross-bridge 0.8 mi (1.3 km) northwest of Highway 164, 1.2 mi (1.9 km) upstream from mouth and about 2.0 mi (3.2 km) northeast of Naranjito plaza. DRAINAGE AREA.--4.0 mi' (10.3 km*). PERIOD OF RECORD.--Water year 1979 to current year. WATER-QDALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 15... DEC 10... FBB 1992 25... APR 01... JUN 08... AOQ 05... TIME 0930 1100 0945 0840 0810 0820 DIS- CHARGE, INST. CUBIC FEET PER 3.7 6.5 4.9 12 17 19 SPE- CIFIC CON- DUCT- ANCE SECOND (US/CM) 384 374 315 299 364 250 PH WATER WHOLE FIELD TBMPBR- (STAND- ATURB ARD WATER UNITS) (DBG C) 8.0 8.1 8.1 7.5 8.0 7.4 24.5 23.0 22.5 22.5 24.5 25.0 TUR- BID- ITY (NTU) 1.7 2.6 0.50 25 0.80 17 OXYGEN, DIS- SOLVED (MG/L) 7.6 8.2 7.0 8.8 8.0 6.0 OXYGEN, OXYGEN DIS- DEMAND, SOLVED (PER- CENT SATUR- CHBM- ICAL (HIGH LEVEL) ATION) (MG/L) 83 12 98 <10 77 101 94 61 12 22 10 27 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K1800 700 190 K7300 K910 2000 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) K1300 940 470 5500 2300 52000 DATE OCT 1991 15... DEC 10... FBB 1992 25... APR 01... JUN 08... AUG 05... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MG/L TOT FLD SOLVED AS MG/L AS (MG/L CACO3) CAC03 150 120 180 110 34 27 47 25 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS NA) 15 13 14 11 21 15 24 14 SODIUM AD- SORP- TION RATIO 0.8 0.6 0.8 0.6 ALKA- POTAS- LINITY CHLO- SIUM, WAT WH SULFATB RIDE, DIS- TOT FBT SULFIDB DIS- DIS- SOLVED FIELD TOTAL SOLVED SOLVED (MG/L MG/L AS (MG/L (MG/L (MG/L AS K) 3.0 4.4 2.6 2.4 CACO3 120 130 120 110 130 100 AS S) AS S04) AS CL) <0.5 18 <0.5 18 <0.5 20 17 29 26 33 21 DATE OCT 1991 15... DEC 10... FBB 1992 25... APR 01... JUN 08... AUG 05... FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.10 0.20 0.20 0.10 SOLIDS, RESIDUE SILICA, SUM OF SCLIDS, TOTAL DIS- CONSTI- SOLVBD TUBNTS, (MG/L AS SI 02) 26 20 26 19 DIS- SOLVED (MG/L) 218 DIS- AT 105 SOLVED DBG. C, (TONS SUS- PENDED (MG/L) PER DAY) 2.17 190 6.04 269 12.3 169 8.67 1 15 9 11 9 224 NITRO- NITRO- NITRO- GEN, GEN, GEN, NITRATE NITRITE NO2+NO3 TOTAL TOTAL TOTAL (MG/L (MG/L (MG/L AS N) AS N) AS N) 1.57 1.49 1.59 1.18 0.990 0.820 0.030 0.010 0.010 0.020 0.010 0.020 1.60 1.50 1.60 1.20 1.00 0.840 NITRO- GEN, NITRO- GEN, AMMONIA ORGANIC TOTAL TOTAL (MG/L (MG/L AS N) 0.080 0.010 0.020 0.040 0.010 0.030 AS N) 0.22 0.19 0.16 0.67 non-ideal count 142 RIO DB LA PLATA BASIN 50044850 RIO GOADIANA NEAR NARANJITO, PR--Continued HATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 15... DEC 10... FBB 1992 25... APR 01... JUN 08... AUG 05... DATE OCT 1991 15... DEC 10... FEB 1992 25.. . APR 01... JUN 08.. . AUG 05... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.30 0.20 <0.20 0.20 <0.20 0.70 IRON, TOTAL RECOV- ERABLE (UG/L AS FE) NITRO- GEN, TOTAL (MG/L AS N) 1.9 1.7 — 1.4 — 1.5 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N03) 8.4 7.5 -- 6.2 -- 6.8 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.470 0.320 0.280 0.160 0.180 0.410 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) ARSENIC TOTAL (UG/L AS AS) <1 -- -- 1 -- -- SELE- NIUM, TOTAL (UG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (OG/L AS BA) <100 — — <100 — — SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) 60 -- -- 20 — -- ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 — — <1 — -- CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) 1 -- -- 8 -- -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CO) <10 — — 10 — -- MBTHY- LBNB BLUB ACTIVE SUB- STANCE (MG/L) 140 2100 20 50 <0.10 0.20 <1 <0.010 <0.010 0.05 0.03 RIO DB LA PLATA BASIN 143 50045000 LAGO LA PLATA AT DAMSITE, PR LOCATION.--Lat 18°20'40", long 66<>14'10", Hydrologic Unit 21010005, 2.9 ml (4.7 km) at northeast of Plaza de Naranjito, 2.7 ml (4.3 km) West of Road 167, km 15.3, Buena Vista, Bayaaon, 5.2 mi (8.4 km) east of Plaxa de Corozal. DRAINAGE ARBA.--181 mi> (469 km'). ELEVATION RECORDS PERIOD OF RECORD.—February 1989 to current year. GAGB.—Water-stage recorder. Datum of gage is mean sea level. REMARKS.--Lago La Plata first construction phase was completed in 1974 and the second construction phase to provide the spillway with bascule gates was completed in October 1989. The maximum storage is 37,000 ac-ft (45.6 hn?) and its purpose is the supply of water for domestic and industrial use. La Plata Dam is a concrete gravity structure located across the Rio de la Plata, the dam has an overall length of 774 ft (236 m) and a maximum height of about 131 ft (40 m). The dam spillway is provided with 6 bascule gates. The spillway crest has a total clear length of 690 ft (210 m), an elevation of 155 ft (47 m). The Dam is owned and operated by Puerto Rico Aqueduct and Sewer Authority. Gage-height and precipitation satellite telemetry at station. EXTREMES OBSERVED FOR PERIOD OF RECORD.--Maximum elevation, 167.02 ft (50.91 m), Jan. 5, 1992; minimum elevation, 144.88 ft (44.16 m), Oct. 29, 1991. EXTREMES FOR CURRENT YEAR.--Maximum elevation, 167.02 ft (50.91 m), Jan. 5; minimum elevation, 144.88 ft (44.16 m), Oct. 29. Capacity Table (based on data from Puerto Rico Aqueduct and Sewer Authority) Elevation, in feet Contents, in acre-feet Elevation, in feet Contents, in acre-feet 98.43 2,760 164.05 28,550 131.24 11,360 170.61 33,160 154.60 22,720 175.52 37,040 ELEVATION (FEET NGVD), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY OBSERVATION AT 24:00 VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 148.72 146.45 151.12 147.57 154.68 153.25 152.10 154.65 154.92 153.88 149.93 152.72 2 148.88 146.72 151.06 147.39 154.64 153.10 154.50 154.92 154.96 153.73 149.80 152.55 3 148.87 146.83 151.02 147.22 154.76 152.93 154.87 154.83 154.92 153.55 149.67 152.42 4 148.83 146.82 151.00 147.04 154.88 152.82 154.78 154.73 154.88 153.36 149.66 152.31 5 148.75 146.81 151.01 166.92 154.82 152.69 154.67 154.63 154.85 153.17 150.56 152.33 6 148.58 146.79 150.95 A 154.77 152.53 154.50 154.78 154.80 152.97 155.14 152.44 7 148.45 147.43 150.83 155.21 154.85 152.39 154.46 154.71 154.79 152.79 155.11 152.34 8 148.51 148.76 150.73 155.13 154.87 152.30 154.33 154.66 154.79 152.70 155.02 152.18 9 148.43 149.76 150.66 155.05 154.81 152.16 154.21 154.56 154.81 152.68 155.15 152.04 10 148.32 150.06 150.52 155.04 154.77 152.14 154.30 154.49 154.81 152.56 154.95 151.98 11 148.16 150.12 150.36 154.97 154.72 152.12 154.19 154.45 154.88 152.45 154.84 151.87 12 148.04 150.11 150.23 154.95 154.77 152.00 154.06 154.28 154.96 152.30 154.85 151.70 13 147.83 150.12 150.08 154.99 154.75 151.93 153.92 154.09 154.92 152.16 154.81 151.53 14 147.64 150.01 149.93 154.96 154.69 151.81 153.89 153.89 154.95 152.05 154.81 151.33 15 147.42 149.90 149.78 154.90 154.64 151.68 153.76 153.68 154.91 151.96 154.75 151.16 16 147.21 149.81 149.16 155.36 154.54 151.50 153.66 153.97 154.90 151.86 154.71 151.02 17 146.97 149.73 149.30 154.94 154.47 1S1.39 153.95 154.19 154.87 151.77 154.67 150.98 18 146.79 149.70 149.09 154.88 154.38 151.35 153.88 154.76 154.89 151.67 154.58 150.99 19 146.58 149.53 148.89 154.84 154.26 151.28 153.76 155.12 154.82 151.60 154.47 151.41 20 146.41 149.38 148.84 154.84 154.16 151.13 154.83 154.93 154.76 151.45 154.33 153.83 21 146.23 149.28 148.97 154.83 154.06 150.99 154.97 155.37 154.81 151.31 154.21 155.37 22 146.01 149.31 149.02 154.82 153.98 150.92 154.82 155.02 155.00 151.17 154.07 155.04 23 145.82 149.41 148.91 154.81 153.85 150.79 154.67 156.83 154.92 151.14 153.94 154.92 24 145.64 149.87 148.77 154.81 153.76 150.65 154.50 155.29 154.82 151.23 153.77 154.81 25 145.50 150.27 148.56 154.81 153.67 150.48 154.31 155.16 154.72 151.08 153.60 154.72 26 27 28 29 30 31 145.41 145.22 145.01 144.96 145.23 146.15 150.35 150.33 150.83 151.07 151.14 148.39 148.22 148.15 147.99 147.85 147.71 154.82 154.80 154.80 154.79 154.74 154.70 153.60 153.52 153.44 153.33 ___ 150.31 150.87 152.29 152.41 152.29 152.22 154.14 153.95 153.74 153.88 153.96 155.48 155.03 154 . 92 154.90 154.86 154.95 154.62 154.47 154.33 154.18 154.06 150.95 150.84 150.65 150.42 150.23 150.10 153.46 153.35 153.21 153.09 152.96 152.85 154.58 154.46 154.29 154 . 10 153.99 MEAN 147.12 149.22 149.58 —— 154.36 151.83 154.19 154.78 154.78 151.93 153.56 152.85 MAX 148.88 151.14 151.12 —— 154.88 153.25 154.97 156.83 155.00 153.88 155.15 155.37 MIN 144.96 146.45 147.71 —— 153.33 150.31 152.10 153.68 154.06 150.10 149.66 150.98 A No gage-height record. 144 RIO DB LA PLATA BASIN 50045010 RIO DB LA PLATA BELOW LA PLATA DAM, PR LOCATION.—Lat 18°20'45', long 66°14'17", Hydrolooic Unit 21010005, 2.8 mi (4.5 km) west of Road 167, km 15.3, Buena Vista, Bayam6n, 5.0 mi (8.0 km) east of Plaxa de Coroxal, 3.0 mi (4.8 km) northeast of Plaxa de Naranjito. DRAINAGE ARBA.--173 mi* (448 km*). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—July 1989 to current year. GAGE.—Nater-stage recorder. Elevation of gage i« 164 ft (30 m), from topographic map. REMARKS.—Records poor. Regulation at all stages by Puerto Rico Aqueduct and Sewer Authority reservoir upstream from gage. Gage-height satellite telemetry at station. DAY DISCHARGE, CUBIC FEET PER SECOND, NATBR YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUO SBP 1 .01 .16 2 .00 .35 3 .00 .40 4 .00 .25 5 .00 .15 6 .00 .10 7 .00 .02 8 .00 .00 9 .00 .01 10 .00 .01 11 .00 .02 12 .00 .02 13 .00 .06 14 .00 .06 15 .00 .06 16 .00 .04 17 .00 .04 18 .00 .02 19 .00 .02 20 .00 .02 21 .00 .13 22 .00 .49 23 .00 .26 24 .00 .78 25 .01 .31 26 .11 .18 27 .13 .15 28 .12 .24 29 .43 .28 30 .46 .18 31 .22 TOTAL 1.49 4.81 MEAN .048 .16 MAX .46 .78 KEN .00 .00 AC -FT 3.0 9.5 CFSM .00 .00 IN. .00 .00 e Estimated STATISTICS OF MONTHLY MEAN MEAN 437 47.5 MAX 1107 107 (NY) 1991 1991 KEN .048 .16 (NY) 1992 1992 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE ANNUAL RUNOFF (AC- FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCBBDi .15 .15 .18 .23 .14 .11 .08 .12 .21 .21 .15 .12 .12 .25 .14 .12 .10 .10 .02 .20 .38 .17 .12 .10 .08 .06 .06 .17 .25 .15 .11 4.55 .15 .38 .02 9.0 .00 .00 DATA 28.4 84.8 1991 .14 1990 .10 .09 .06 .04 16300 27400 1500 576 360 374 279 201 220 213 137 226 531 207 109 63 47 41 33 27 28 30 26 23 24 14 7.6 48996.89 1581 27400 .04 97190 9.15 10.55 2.4 .78 2.1 50 53 26 30 61 43 24 13 17 19 7.4 1.7 .42 .17 .09 .06 .03 .02 .03 .02 .01 .01 .00 .00 .00 .00 ___ 351.24 12.1 61 .00 697 .07 .08 FOR NATBR YEARS 1989 550 1581 1992 .19 1990 77.5 222 1991 .27 1990 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .01 .00 .00 .00 .00 .46 1.7 .85 .16 .03 3.21 .10 1.7 .00 6.4 .00 .00 - 1992 44.8 83.2 1990 .10 1992 FOR 1991 CALENDAR YEAR 12317 33 1330 24430 2 83 .15 .7 Jul 16 .00 Jun 17 .00 Aug 7 .20 .65 .23 .00 .01 .00 29 20 2.9 .36 .08 .02 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 6.7 95 46 10 .54 .05 .00 .00 .00 .05 .36 --- 211.07 7.04 95 .00 419 .04 .05 .27 209 91 13 1.3 10 12 2.9 .36 .07 .01 .01 .00 .00 .00 1.5 .47 4.6 158 154 430 305 1020 3840 705 4520 796 365 209 140 86 105 108 91 42 24 15 8.8 7.5 10 8.6 160 183 294 309 172 112 78 48 37 18 11 104 99 50 18 2.7 .37 .14 .06 .03 —— 13074.49 2116.20 422 4520 .00 25930 2.44 2.81 70.5 309 .03 4200 .41 .46 .02 .02 .02 .02 .02 .01 .01 .02 .25 .12 .16 .19 .11 .11 .08 .12 .14 .12 .09 .12 .09 .14 .10 .13 .14 .14 .10 .11 .09 .04 .02 2.85 .092 .25 .01 5.7 .00 .00 .01 .00 .00 .12 .49 112 295 160 154 148 57 30 29 17 14 9.1 3.8 .93 .13 .03 .01 .00 .00 .00 .00 .13 .07 .01 .00 .00 .00 1030.83 33.3 295 .00 2040 .19 .22 .00 .00 .00 .00 .00 .01 .01 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .07 .34 350 e371 149 44 9.0 .69 .03 .01 .01 .01 924.18 30.8 371 .00 1830 .18 .20 , BY NATBR YEAR (NY) 14.9 27.7 1990 7.04 1992 FOR 1992 66721 182 27400 127000 34 132300 1 14 148 162 422 1992 2.00 1991 NATBR YEAR .81 Jan 6 .00 Oct 2 .00 Oct 2 Jan 5 .76 Jan 5 .05 .36 .12 .00 30.0 70.5 1992 .16 1991 21.8 64.7 1991 .092 1992 NATBR 121 182 37 27400 127000 34 87900 9 174 8.34 33.3 1992 .020 1989 273 1047 1989 .001 1991 YEARS 1989 - 1992 .8 Jan .00 Jul .00 Jul Jan .76 Jan .70 .54 .49 .00 1992 1990 6 1992 14 1989 14 1989 5 1992 5 1992 RIO DB LA PLATA BASIN 50045010 RIO DB IA PIATA AT BELOW IA PIATA DAM, PR—Continued HATER-QUALITY RECORDS PERIOD OF RECORDS.-- Hater years 1990 to current year. INSTROMBNTATION.-- Automatic sediment sampler and DH-48. PERIOD OF DAILY RECORD.-- SOSPBNDBD-SBDIMENT DISCHARGE! October 1989 to September 1992 EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATION! Maximum daily mean, 2,180 mg/L Jan. 06, 1992; Minimum daily mean, <.05 mg/L several days. SEDIMENT LOADSi Maximum daily mean, 362,000tons (328,OOOtonnes) Jan. 06, 1992; Minimum daily mean, 0.00 ton (0.00 tonne) several days. EXTREMES FOR HATER YEARS 1990-92.-- 145 Hater Suspended- sediment concentration (mg/L) Year 1990 1991 1992 2, maximum 848 (Mar. 243 (Oct. 180 (Jan. Suspended- sediment discharge (tons per day) •ilniflUM pmxl IIPIIP aU.ni.MUM 14) <.05 21) <.05 06) <.05 SEDIMENT DISCHARGE, SUSPENDED DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CFS) 159 246 196 223 234 170 109 89 76 68 62 54 45 56 47 36 275 170 74 65 263 503 1310 687 184 290 204 94 .84 152 103 MEAN CONCEN- TRATION (MG/L) OCTOBER 17 24 21 22 22 19 14 12 11 10 10 9 8 9 8 6 26 19 11 10 25 38 73 48 20 27 22 13 13 17 13 SEDIMENT DISCHARGE (TONS/DAY) 7.5 16 11 13 14 8.5 4 2.9 2.3 1.9 1.6 1.3 .93 1.4 1 .63 19 8.5 2.2 1.8 18 52 259 89 9.7 21 12 3.2 3.2 7.1 3.7 (Several (Several (Several days) days) days) 259 5,760 362,000 (Oct. 23) (Oct. 21) (Jan. 06) .00 .00 .00 (Several (Several (Several days) days) days) (TONS/DAY), HATER YEAR OCTOBER 1989 TO SEPTEMBER 1990 MEAN MEAN CONCBN- DISCHARGE TRATION (CFS) 114 77 50 37 40 90 87 87 92 55 38 34 33 33 28 24 20 17 29 25 17 10 6. 4. 3. 1. . - (MG/L) NOVEMBER 14 11 8 7 7 12 12 12 12 9 7 7 6 6 6 5 4 4 6 5 4 4 2 4 1 3 1 2 8 2 81 < 38 < 25 < 15 < .__ SEDIMENT DISCHARGE (TONS /DAY) 4.4 2.3 1.1 .66 .76 3 2.8 2.8 3.1 1.3 .69 .61 .54 .54 .42 .32 .24 .19 .44 .34 .19 .10 .06 .00 .02 .01 .5 .00 .5 .00 .5 .00 .5 .00 --- MEAN MEAN CONCBN- DISCHARGB TRATION (CFS) . . . . • . . . • . . . • a . . . • . . . . • . . . 1. . (MQ/L) DECEMBER 10 < 07 < 04 < 03 < 03 < 02 < 02 < 01 < 01 < 01 < 01 < 02 < 02 < 02 < 04 < 09 < 13 < 13 < 13 < 18 < 18 < 17 < 16 < 15 < 12 < 10 < 10 < 16 3 1 < 74 < 39 < SEDIMENT DISCHARGE (TONS/DAY) .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .01 .00 .00 TOTAL 6328 597.36 1053.79 26.93 4.48 0.01 146 RIO DK LA PLATA BASIN 50045010 RIO DK LA PLATA BELOW LA PLATA DAM, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1989 TO SEPTEMBER 1990 »AY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CFS) .31 .27 .22 .19 .15 .15 .15 .13 .13 .13 .12 .11 .10 .07 .12 .10 .17 .15 .11 .53 .50 .27 .17 .31 .20 .12 .10 .11 .17 .28 .34 MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) JANUARY .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) FEBRUARY .18 .11 .15 .13 .12 .05 .09 .28 .26 .15 .08 .03 .01 .95 .62 .44 .30 .23 .48 .32 .22 .28 .50 .58 .34 .26 .21 .20 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .01 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 MEAN DISCHARGE (CFS) .34 .33 .28 .33 .20 .13 .08 .04 .22 .31 1.7 2.8 511 848 51 178 269 187 104 56 54 48 44 41 36 31 28 25 22 20 18 MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) MARCH .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 2 .01 3 .02 38 53 55 126 9 1.5 19 9.2 25 18 20 10 13 3.7 9 1.4 9 1.3 8 1 7 .89 7 .79 6 .63 6 .49 6 .42 5 .34 5 .28 4 .24 4 .10 TOTAL 5.98 0.00 7.57 0.01 2577.76 RIO DB LA PLATA BASIN 50045010 RIO DB LA PLATA BELOW LA PLATA DAM, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1989 TO SEPTEMBER 1990 147 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 16 14 12 10 8.2 6.5 5.3 4.2 3.4 3.0 2.0 1.7 1.0 .67 .36 .25 1.8 12 16 58 98 92 58 31 32 76 81 73 64 51 ___ APRIL 3 3 3 2 2 2 2 4 <. 5 <.5 <.5 2* 4 4 9 13 12 9 6 6 11 11 11 10 9 ___ MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MAY .17 .15 .12 .10 .08 .06 .04 .03 .02 .02 .01 .01 .01 .00 .00 .00 .01 .12 .17 31.4 3.4 3.1 1.4 .49 .52 2.3 2.5 2.1 1.7 1.2 ___ 45 42 36 30 26 22 22 257 663 71 76 74 71 71 67 61 50 40 31 25 30 24 20 17 14 11 9.7 8.2 6.0 5.0 4.0 8 7 6 6 5 5 5 24 46 10 11 11 10 10 10 10 8 7 6 5 6 5 3 3 3 .93 .82 .63 .47 .37 .28 .28 17 82 2 2.3 2.2 2 2 1.8 1.6 1.1 .76 .49 .34 .47 .32 .24 .19 .15 .11 .10 .08 .05 .04 .03 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) JUNE 3.4 3.1 2.5 2.4 2.7 2.3 1.7 1.4 1.1 1.2 1.1 .96 .90 1.3 168 260 89 26 5.7 1.4 .80 .67 .67 .62 .81 .66 .58 .55 .51 .52 ___ 2 2 3 3 3 3 3 3 3 3 3 4 <.5 3 18 24 12 6 3 3 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 ___ .02 .02 .02 .02 .02 .02 .01 .01 .01 .01 .01 .01 .01 .01 8.4 17 2.9 .40 .05 .01 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 TOTAL 832.38 51.23 1928.9 121.15 582.55 148 RIO DE LA PLATA BASIN 50045010 RIO DB LA PLATA BELOW LA PLATA DAM, PR—Continued SEDIMENT DISCHARGE, SUSPENDED {TONS/DAY), WATER YEAR OCTOBER 1989 TO SEPTEMBER 1990 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL YEAR MEAN DISCHARGE (CFS) .63 .64 .57 .35 .29 .20 .15 .12 .13 .28 .12 .03 .00 .00 .00 .31 1.4 .79 .82 2.0 .98 .67 .36 .43 .39 .28 .20 .14 1.0 .66 .30 14.24 13798.69 MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) JULY •c.5 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .01 .00 .00 .01 .01 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 0.03 1073.58 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AUGUST .16 .14 .17 .08 .04 .02 .06 .10 .06 .24 .27 .13 .14 .23 .12 .05 .02 .01 .01 .00 .00 .00 .00 .00 .08 .11 .02 .00 .00 .00 .00 2.26 30 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 0.00 MEAN DISCHARGE (CFS) CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) SEPTEMBER .00 .00 .01 .08 .41 .40 1.2 .91 .53 .43 .83 .92 .59 .73 1.2 1.3 1.1 1.2 1.7 1.7 1.4 .82 .48 .33 .31 171 154 80 29 8.2 460.78 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 3 3 3 3 2 2 3 <.S «.S <.S «.S 9 7 2 6 4 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .01 .01 .01 .01 .01 .01 .01 .00 .00 .00 .00 8.6 7.2 2.5 .44 .08 18.89 RIO DE LA PI ATA BASIN 149 50045010 RIO DE LA PLATA BELOW LA PLATA DAM, PR—Continued SEDIMENT DISCHARGE, SOSFENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SBPTBMBBR 1991 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) OCTOBER 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 110 140 88 107 95 65 629 218 579 1060 410 145 417 521 1180 2720 1500 2050 3470 484 8790 1010 391 308 845 3810 1670 572 374 254 302 14 16 12 13 12 10 13 22 42 65 33 17 34 39 69 115 79 94 134 37 243 63 32 28 55 142 84 41 32 25 27 4.1 6.2 2.9 3.9 3.2 1.8 73 13 65 186 37 6.5 38 55 220 840 320 522 1260 48 5760 173 34 23 126 1460 378 64 32 17 22 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) NOVEMBER 218 182 178 154 155 171 149 124 125 120 101 92 82 69 62 63 70 67 90 65 78 110 102 102 84 51 55 54 55 185 22 20 19 17 17 17 17 15 15 15 13 12 12 11 10 10 11 11 12 10 11 14 13 13 12 9 9 9 9 20 13 10 9.2 7.2 7.3 8.6 6.8 5 5.1 4.8 3.6 3.1 2.7 2 1.6 1.7 2 1.9 3 1.8 2.4 4.1 3.6 3.6 2.7 1.2 1.3 1.3 1.3 9.8 MEAN DISCHARGE (CPS) 166 152 377 298 152 86 53 37 28 22 18 16 19 16 16 31 35 26 13 5.6 2.1 1.5 1.3 1.5 1.7 1.4 1.2 5.3 52 182 813 CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) 18 17 31 27 17 12 8 7 6 5 6 6 5 4 33 2 2 3 2 2 3 3 3 8 19 53 8.2 7.1 32 22 7.1 2.8 1.2 .66 .42 .28 .20 .17 .22 .17 .17 .49 .60 .37 .14 .05 .01 .01 .01 .01 .01 .01 .01 .04 1.2 9.5 117 TOTAL 34314 11794.6 3213 131.7 2629.6 212.15 150 RIO DB LA PLATA BASIN 50045010 RIO DB LA PLATA BELOW LA PLATA DAM, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) JANUARY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL 686 224 123 81 56 108 121 69 71 101 88 72 55 48 41 39 32 26 21 15 10 6.7 5.3 6.3 7.1 6.3 2.5 1.9 1.9 1.7 2.1 2128.8 46 23 15 11 9 14 15 11 10 13 12 11 9 8 7 7 6 5 5 4 4 3 3 3 4 3 3 2 2 2 2 86 14 5 2.5 1.4 4 4.8 2 2 3.6 2.9 2.1 1.3 1 .79 .72 .52 .37 .26 .16 .10 .06 .04 .06 .07 .06 .02 .01 .01 .01 .01 135.87 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) FEBRUARY 2.2 2.1 2.0 3.3 1020 452 337 202 117 77 180 291 1070 329 207 109 96 165 350 289 246 192 135 91 68 60 62 72 ___ ___ ___ 6226.6 2 2 2 2 64 35 29 20 15 11 19 27 65 28 21 14 13 18 30 27 24 19 16 12 10 9 10 11 ___ ___ ___ .01 .01 .01 .02 175 43 26 11 4.6 2.3 9.4 21 189 25 12 4 3.3 8.1 28 21 16 10 5.8 3 1.9 1.5 1.6 2.1 ___ ___ ___ 624.65 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MARCH 75 91 92 54 37 34 38 44 47 35 33 34 31 29 24 15 7.3 4.1 1.6 1.2 .50 217 267 123 38 9.4 86 74 28 8.7 2.8 1581.60 11 12 12 9 7 6 7 7 8 6 6 6 6 6 5 4 4 3 2 3 1 22 25 15 7 4 12 11 6 3 3 2.2 3 3.1 1.3 .66 .57 .69 .89 1 .60 .54 .57 .49 .44 .32 .16 .07 .03 .01 .01 .00 13 18 5 .69 .09 2.8 2.2 .42 .08 .02 58.95 RIO OB LA PLATA BASIN 157 50045010 RIO DB LA PLATA BELOW LA PLATA DAM, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 2.0 1.9 2.7 2.9 3.0 2.9 2.9 3.8 4.2 3.2 3.4 3.5 4.5 3.6 68 107 38 11 3.9 3.3 3.3 3.1 2.3 1.9 1.8 1.7 1.5 1.4 1.3 1.2 APRIL 2 2 3 3 2 3 3 3 3 2 2 2 3 3 10 13 7 4 3 3 2 2 3 2 2 2 2 3 3 3 ___ .01 .01 .02 .02 .02 .02 .02 .03 .03 .02 .02 .02 .04 .03 1.9 3.9 .69 .11 .03 .03 .02 .02 .02 .01 .01 .01 .01 .01 .01 .01 MEAN DISCHARGE (CFS) 1.1 1.1 1.2 1.6 1.2 1.1 1.0 2.5 1.5 .68 .49 .48 .62 14 22 5.7 .77 .33 .29 .26 .25 .17 .14 .12 1.4 .62 .42 .29 .23 .19 .26 MAY 3 33 3 3 3 3 4 3 2 .01 .01 .01 .01 .01 .01 .01 .02 .01 .00 .00 .00 .00 .15 .28 .05 .00 .00 .00 .00 .00 .00 .00 .00 .01 .00 .00 .00 .00 .00 .00 MEAN MEAN CONCBN- DISCHARGE TRATIOI (CFS) (MG/L) JUNE .46 .41 .29 .23 .17 .15 .15 .12 .10 .07 .04 .04 .03 .02 .01 .01 .00 .45 .47 .28 .17 .10 .19 .17 .12 .08 .03 .02 .02 .41 • SEDIMENT I DISCHARGE (TONS/DAY) .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 TOTAL 295.2 7.10 62.01 0.59 4.81 0.00 152 RIO DE LA PLATA BASIN 50045010 RIO DB LA PLATA BELOW LA PLATA DAM, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 IS 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION 'DISCHARGE (CFS) (MG/L) (TONS/DAY) JULY .45 .5 .27 .20 .21 .16 .09 .25 .44 .31 .20 .13 .07 .05 .02 .05 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 1330 74 507 38 121 IS 36 6 7.0 3 1.0 4 .38 .5 .18 .5 .11 .5 .08 .5 .04 .5 .03 .5 .10 .5 .15 .5 .07 .5 .39 .5 TOTAL 2006.43 YEAR • 52462.90 Estimated .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 265 52 4.8 .63 .06 .01 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 322.50 13288.11 MEAN MEAN MEAN CONCBN- SEDIMENT MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) (CFS) (MG/L) (TONS/DAY) AUGUST SEPTEMBER .39 .17 .08 .03 .01 .01 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 • .02 • .03 • .02 • .03 • .02 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .5 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .02 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .5 .00 e.OO .5 e.OO .00 .5 e.OO .00 .5 e.OO .01 .5 e.OO .01 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .5 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .5 e.OO .5 .00 .5 .00 .5 .00 .5 .00 .5 «.00 —— —— --- 0.81 0.00 0.04 0.00 I. ^ 8 O O : g s s ^ 5 "y 3 5 q3 * a i s * s i 3 & i« s 8 S ^ 2 a I j, ,,o,o ..... ..... ..... ..... ...... . IBj. i 9| lAiAtAtAtA IAIAIAIAIA IAIAIAIAIA B j H U> I/I CB n ^ r« W f« «•« r« IA M M IA ^ M O O f« O CD r- M O «0 tt 10 t-IA IA t-l IA ,| *1*«!1 --.-•!«! 11-"- ---««! «-1-« •«-«!-•; J 3|8 s Ip •««.«« «««.«• •«•.«•. ««•.«« ••«•«. ««.««•! - ««i «s| I 9B ^ * ^ ^ » ««IA^»IA «IAV0V0IA IAIAIAIAIA IA IA IA I/I IA IAIA1AIA1AI I Sn3 H I! m\ M Vk l/t O l/t I/I OMO»^r^ C4C4U>U>M> ^^MMM l*|flh*fl€Dr^ 00 U> ^> 00 00 I r<4 9 *4<»l*»r««-4 «400OO OOOOO OOOOO f-4*r4r*f") r-« r-l M M •-» | CD a" M ^- OOOOO OOOOO OOOOO OOOOO OOOOO OOOI-4OO i-t |<O>< OOOOO OOOOO OOOOO OOOOO OOOOO OOOOOO O !ljj ..... ..... ..... ..... ..... ...... ^ ssi WQ Jj I Z It IAIAIAIAIA lAUtlAIAIA IAIAIAIA« ««««« IA I/I U> I/I « ««n««« I §23 a : U |4 ^. O HI t-IOOOO OOOOO OOOOO OOOOO OOOOr-4 •-( n p« ri >fi r» <* O ooooo ooooo ooooo ooooo ooooo rt r-t ^ <« <« r» •<» *2j ..... ..... ..... ..... ..... ...... ^ awo >• i-t r» n 4 i-t r» o ^ i/i 154 RIO DB LA PLATA BASIN S004S010 RIO DB LA PLATA BELOW LA PLATA DAM, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 IS 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CFS) .10 .09 .06 .04 16300 27400 1500 576 360 374 279 201 220 213 137 226 531 207 109 63 47 41 33 27 28 30 26 23 24 14 7.6 MEAN CONCEN- TRATION (MG/L) JANUARY 10 10 10 10 1870 2180 199 89 63 60 126 40 40 39 30 39 82 38 28 25 25 25 25 24 22 21 17 13 8 5 3 SEDIMENT DISCHARGE (TONS/DAY) .00 .00 .00 .00 305000 362000 965 141 62 58 113 22 22 22 13 SO 138 21 9.0 4.4 3.2 2.7 2.1 1.7 1.6 1.6 1.2 .83 .52 .21 .06 FEBRUARY 2.4 .78 2.1 SO S3 26 30 61 43 24 13 17 19 7.4 1.7 .42 .17 .09 .06 .03 .02 .03 .02 .01 .01 .00 .00 .00 .00 1 1 1 12 13 7 7 14 11 6 4 4 5 3 3 4 5 12 14 8 5 5 4 2 1 1 1 1 1 .01 .00 .03 1.8 1.8 .63 .71 2.1 1.3 .42 .15 .21 .23 .07 .01 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 MEAN DISCHARGE (CFS) .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .01 .00 .00 .00 .00 .46 1.7 .85 .16 .03 MEAN CONCEN- TRATION (MG/L) MARCH 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 SEDIMENT DISCHARGE (TONS/DAY) .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 TOTAL 48996.89 668656.12 351.24 9.47 3.21 0.00 RIO DB LA PLATA BASIN 50045010 RIO DB LA PLATA BELOW LA PLATA DAM, PR—Continued SEDIMENT DISCHARGB, SUSPENDED (TONS/DAY), WATER YBAR OCTOBER 1991 TO SEPTEMBER 1992 755 MEAN MEAN CONCBN- SEDIMENT DISCHARGB TRATION DISCHARGB DAY (CFS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 .01 .00 29 20 2.9 .36 .08 .02 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 6.7 95 46 10 .54 .05 .00 .00 .00 .05 .36 ___ APRIL 1 1 8 5 1 1 1 1 1 <.05 1 1 1 1 1 1 1 1 1 3 20 15 3 1 1 1 1 1 1 1 .00 .00 .84 .37 .02 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .15 5.2 2.0 .13 .00 .00 .00 .00 .00 .00 .00 ___ MEAN MEAN CONCBN- SEDIMENT DISCHARGB TRATION DISCHARGB (CFS) (MG/L) (TONS/DAY) MEAN MEAN CONCBN- SEDIMENT DISCHARGB TRATION DISCHARGB (CFS) (MG/L) (TONS/DAY) MAY JUNE .27 209 91 13 1.3 10 12 2.9 .36 .07 .01 .01 .00 .00 .00 1.5 .47 4.6 158 154 430 305 1020 3840 705 4520 796 365 209 140 86 1 12 13 4 1 3 5 2 1 1 1 1 1 1 1 1 1 2 15 20 64 33 91 411 105 461 105 62 44 40 39 .00 7.0 3.9 .22 .00 .13 .16 .03 .00 .00 .00 .00 .00 .00 .00 .01 .00 .07 12 8.2 148 48 1250 6160 209 10200 256 63 25 15 11 105 108 91 42 24 15 8.8 7.5 10 8.6 160 183 294 309 172 112 78 48 37 18 11 104 99 50 18 2.7 .37 .14 .06 .03 91 55 61 56 45 39 37 37 36 34 44 29 27 24 21 20 20 20 20 18 16 23 19 16 12 10 10 9 7 6 26 15 14 6.5 2.9 1.5 .90 .77 .84 .88 16 17 18 20 12 5.8 4.0 2.9 2.0 .92 .70 6.9 5.0 2.1 .69 .08 .01 .00 .00 .00 TOTAL 211.07 8.71 13074.49 18416.72 2116.20 183.39 756 RIO DB LA PLATA BASIN 50045010 RIO DB LA PLATA BBLOW LA PLATA DAM, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL YEAR MEAN MEAN CONCBN- DISCHARQB TRATION (CFS) (MG/L) .02 .02 .02 .02 .02 .01 .01 .02 .25 .12 .16 .19 .11 .11 .08 .12 .14 .12 .09 .12 .09 .14 .10 .13 .14 .14 .10 .11 .09 .04 .02 2.85 66721.81 JULY 6 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 2 3 5 5 5 5 5 5 6 8 11 14 15 15 14 —— SEDIMENT DISCHARGE (TONS/DAY) MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) AUGUST .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 0.00 687311.25 .01 .00 .00 .12 .49 112 295 160 154 148 57 30 29 17 14 9.1 3.8 .93 .13 .03 .01 .00 .00 .00 .00 .13 .07 .01 .00 .00 .00 1030.83 12 10 10 10 9 10 6 7 9 10 14 8 6 5 5 5 5 5 5 5 5 4 3 3 2 2 2 2 2 2 2 —— .00 .00 .00 .00 .01 3.7 5.3 3.1 3.7 4.1 2.8 .70 .49 .22 .20 .11 .05 .01 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 24.49 e Estimated MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) SEPTEMBER .00 .00 .00 .00 .00 .01 .01 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .07 .34 350 »371 149 44 9.0 .69 .03 .01 .01 .01 924.18 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 4 6 5 3 2 2 2 2 2 2 2 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 4.6 e5.9 1.5 .24 .06 .00 .00 .00 .00 .00 12.30 RIO DB LA PLATA BASIN 50045010 RIO DB LA PLATA BBLON LA PLATA DAM, PR—Continued NATBR QUALITY DATA, NATBR YBAR OCTOBER 1991 TO 8BPTBMBBR 1992 757 PARTICLE-8IZB DISTRIBOTION Of SUSPENDED SEDIMENT DATS JAN 1992 05... 05... 06... TIME 190$ 2219 0359 DIS- CHARGE, INST. CUBIC FEET PER SECOND 5530 12400 41200 8BDI- 8ED. SUSP. PALL SBDI- DIS- MBNT, CHAROB, SUS- SUS- PENDED PBNDBD (MG/L) (T/DAY) 7460 111000 6680 230000 10800 1200000 DIAM. PBRCEN1 FINER THAN .002 MM 39 48 31 BED. 8ED. SUSP. SUSP. FALL FALL DIAM. DIAM. PERCENT PERCEN FINER FINER THAN THAN .004 MM .008 MM 53 69 39 59 82 43 DATE JAN 1992 05... 05... 06... SED. SUSP. FALL DIAM. PERCENT FINER THAN 016 MM 69 87 51 SED. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM 80 92 63 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 97 98 86 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 99 99 97 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 99.7 99.6 99.3 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 99.8 99.8 99.8 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 100 100 100 158 RIO DB LA PLATA BASIN 50045010 RIO DB LA PLATA BELOW LA PLATA DAM, PR—Continued WATER QUALITY DATA, WATER YBAR OCTOBER 1991 TO SBPTBMBBR 1992 SILT AND CLAY PERCENT OP SUSPENDED SBDIMBNT DATE JAN 1992 05... 05... MAY 26... 26... TIME 1849 2359 1744 1944 STREAM- PLOW, INSTAN- TANEOUS (CFS) 1280 123000 2440 21SO SBDI- MBNT, SUS- PENDED (MG/L) 12800 6380 218 226 SBDI- MBNT, DIS- CHARGE, SUS- PENDED (T/DAY) 44100 2120000 1430 1310 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 86 98 97 96 RIO DB LA PLATA BASIN 50046000 RIO DB LA PLATA AT HIGHWAY 2 NEAR TOA ALTA, PR 759 LOCATION.--Lat 18°24'41", long 66°15'39", Hydrologic Unit 21010005, on left bank, at downstream side of bridge on Highway 2, 1.3 mi ( 2.1 km) downstream from Rio Lajas, and 1.6 mi (2.6 km) northwest of Toa Alta, 11.3 mi (18.2 km) downstream from Puerto Rico Aqueduct and Sewer Authority reservoir. DRAINAGE ARBA.--208 mi* (539 km'), excludes 8.2 mi* (21.2 km') upstream from Lago Carite, flow from which is diverted to Rio Guamani. Area at site used prior to September 25, 1984, 200 mi* (518 km>). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—November 1959 (measurement only), January 1960 to current year. Prior to October 1984, published as Rio de la Plata at Toa Alta, PR; October 1984 to September 1988 published as 50046900. GAGE.--Water-stage recorder. Datum of gage is 9.15 ft (2.789 m), above site about 1.0 mi (1.6 km) upstream at mean sea level datum. »n sea level. Prior to October, 1984, at REMARKS.--Records fair except those for estimated daily discharges, which are poor. Regulation at all stages by Puerto Rico Aqueduct and Sewer Authority reservoir upstream from gage. Gage-height and precipitation satellite telemetry at station. EXTREMES OUTSIDE PERIOD OF RECORD.--Approximate discharges and elevations of major floods, as pointed out by local residents are as follows: Sept. 13, 1928, 120,000 ft'/s (3,400 m3 /«), gage height, 37.4 ft (11.40 m); June 16, 1943, 82,000 ftVs (2,322 m'/s), gage height, 34.4 ft (10.48 m), at site 1.0 mi upstream and different datum. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUQ SEP 1 44 55 2 29 69 3 17 83 4 14 55 5 25 59 6 18 27 7 15 19 8 13 26 9 14 28 10 15 24 11 13 21 12 13 24 13 13 21 14 13 22 15 15 21 16 15 24 17 14 23 18 454 23 19 92 23 20 26 29 21 19 57 22 17 232 23 14 86 24 21 160 25 67 54 26 45 35 27 27 26 28 39 23 29 61 25 30 76 24 31 35 TOTAL 1293 1398 MEAN 41.7 46.6 MAX 454 232 MIN 13 19 AC-PT 2560 2770 CFSM .21 .23 IN. .24 .26 e Estimated STATISTICS OP MONTHLY MEAN MEAN 515 460 MAX 4813 2015 (WY) 1971 1985 MIN 35.1 31.0 (WY) 1974 1981 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOPP (AC-FT) ANNUAL RUNOPP (CPSM) ANNUAL RUNOPP (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 22 22 34 46 25 22 16 27 33 31 21 24 23 29 21 21 24 18 18 21 37 20 19 17 16 16 19 18 19 20 27 726 23.4 46 16 1440 .12 .14 DATA 346 1352 1971 23.4 1992 POR 18 17 15 16 5850 15900 2130 766 475 569 370 246 275 236 192 151 588 233 146 104 78 57 57 51 45 45 40 38 38 e32 e29 28807 929 15900 15 57140 4.65 5.36 POR WATER 195 929 1992 16.9 1984 23 19 19 80 63 48 35 38 49 41 30 24 22 24 20 17 15 13 14 12 10 13 12 11 11 9.5 11 11 11 ___ --- 705.5 24.3 80 9.5 1400 .12 .13 YEARS 1960 136 409 1989 16.0 1983 12 11 12 12 12 11 11 15 21 13 12 11 9.3 9.3 11 11 12 16 13 12 10 11 11 8.7 7.9 8.5 19 133 121 33 21 630.7 20.3 133 7.9 1250 .10 .12 - 1992 109 468 1969 8.31 1986 1991 CALENDAR YEAR 26717 73. 2020 13 13 52990 4! 132 28 16 2 Jul 16 Sep 11 Oct 8 37 97 19 17 18 13 19 18 17 15 14 18 23 16 19 14 12 14 13 13 13 13 13 52 43 22 15 13 11 11 12 64 --- 574 19.1 64 11 1140 .10 .11 29 253 156 59 29 90 41 27 21 20 17 15 13 14 12 248 83 67 150 276 345 542 431 5060 805 4800 1010 444 402 206 117 15782 509 5060 12 31300 2.55 2.94 92 95 85 61 45 45 53 55 50 39 73 151 232 246 186 90 70 45 43 36 43 41 86 62 40 28 24 21 19 17 --- 2173 72.4 246 17 4310 .36 .40 17 17 16 16 17 17 15 23 23 18 59 33 29 35 19 30 24 19 65 155 56 25 20 60 37 20 29 35 19 15 14 977 31.5 155 14 1940 .16 .18 14 14 18 71 132 93 259 163 163 186 85 45 47 116 63 38 29 22 21 19 19 18 17 18 15 14 16 13 12 12 26 1778 57.4 259 12 3530 .29 .33 14 11 13 17 18 48 44 19 15 22 34 17 15 15 14 18 22 17 31 311 153 429 189 95 51 34 24 22 19 18 1749 58.3 429 11 3470 .29 .33 , BY WATER YEAR (WY) 197 722 1987 5.07 1984 FOR 1992 56593 155 15900 7 9 118000 26 112300 10 170 23 12 369 1939 1985 7.63 1984 WATER YEAR .2 Jan 6 .9 Mar 25 .9 Mar 20 Jan 5 .39 Jan 5 .77 .54 172 847 1970 11.4 1977 147 690 1961 13.9 1976 WATER 268 824 36 40000 2 2 118000 26 2 194200 1 18 510 94 19 266 1677 1979 16.5 1976 YEARS 1960 - .3 Oct 9 .7 Apr 17 .9 Apr 15 Jan 5 .39 Jan 5 .2 Apr 25 .34 .23 329 1691 1960 19.2 1991 1992 1971 1977 1970 1984 1984 1992 1992 1984 760 RIO DB LA PLATA BASIN 50046000 RIO OB LA PLATA AT HWY 2 NR TOA ALTA, PR--Continued (National stream-quality accounting network station) WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1958 to current year WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 OCT 02 DEC 17 FBB 21 APR 14 JUN 29 ADO 17 OCT 02 DEC 17 FBB 21 APR 14 JUN 29 AUG 17 OCT 02 DEC 17 FBB 21 APR 14 JUN 29 AUG 17 K = DATS TIME 1991 1000 1045 1992 0915 0910 0930 1055 CALCIUM DIS- SOLVED DATS (MG/L AS CA) 1991 52 70 1992 64 58 50 55 SOLIDS, SUM OF CONSTI- TUENTS, DIS- DATB SOLVED (MG/L) 1991 238 304 1992 293 291 248 255 non- ideal count DIS- CHARGE, INST. CUBIC FBBT PER SECOND 30 24 11 14 20 31 MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) 9.4 11 12 12 12 10 SOLIDS, DIS- SOLVED (TONS PER DAY) 19.7 20.5 8.83 11 12.8 21.3 SPE- CIFIC CON- DUCT- ANCE (US /CM) 422 541 505 510 414 432 SODIUM, DIS- SOLVED (MG/L AS NA) 20 24 21 22 20 18 NITRO- GEN, N02+N03 DIS- SOLVED (MG/L AS N) 0.790 0.530 0.510 0.870 0.290 0.490 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.0 7.0 7.6 7.1 7.6 7.3 SODIUM AD- SORP- TION RATIO 0.7 0.7 0.6 0.7 0.7 0.6 NITRO- GEN, AMMONIA DIS- SOLVED (MG/L AS N) 0.080 •cO.010 0.100 0.070 0.030 0.140 TEMPER- ATURE WATER (DBG C) 26.5 24.0 25.5 26.5 29.0 29.0 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 3.4 2.5 3.3 3.5 2.7 3.1 NITRO- GEN, AMMONIA DIS- SOLVED (MG/L AS NH4) 0.10 __ 0.13 0.09 0.04 0.18 TUR- BID- ITY (NTU) 4.0 1.4 3.3 2.4 3.2 10 ALKA- LINITY WAT WH TOT FBT FIELD MG/L AS CAC03 150 200 190 180 150 160 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.50 0.60 1.0 0.60 0.60 0.40 OXYGEN, DIS- SOLVED (MG/L) 6.0 7.6 6.6 6.2 7.0 3.3 SULFATB DIS- SOLVED (MG/L AS SO4) 18 23 27 26 24 21 PHOS- PHORUS TOTAL (MG/L AS P) 0.250 0.190 0.170 0.230 0.080 0.120 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 86 71 89 77 89 74 CHLO- RIDE, DIS- SOLVED (MG/L AS CL) 27 34 34 40 29 28 PHOS- PHORUS DIS- SOLVED (MG/L AS P) 0.240 0.180 0.120 0.190 0.080 0.090 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 3100 270 K91 200 K680 K280 FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.10 0.20 <0.10 0.20 0.20 0.40 PHOS- PHORUS ORTHO, DIS- SOLVED (MG/L AS P) 0.220 0.160 0.100 0.170 0.060 0.090 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 790 320 K60 K20 27 45 SILICA, DIS- SOLVED (MG/L AS SI02) 14 17 15 17 18 16 PHOS- PHATE, ORTHO, DIS- SOLVED (MG/L AS P04) 0.67 0.49 0.31 0.52 0.18 0.28 HARD- NESS TOTAL (MG/L AS CACO3) 170 220 210 190 170 180 SOLIDS, RESIDUE AT 180 DBG. C DIS- SOLVED (MG/L) 245 313 300 298 234 255 ALUM- INUM, DIS- SOLVED (UG/L AS AL> 10 — 20 — 60 10 RIO DB LA PLATA BASIN 50046000 RIO DB LA PLATA AT HWY 2 NR TOA ALTA, PR—Continued (National stream-quality accounting network station) WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 161 DATE OCT 1991 02... DEC 17... FBB 1992 21. .. APR 14... JUN 29... AUG 17... BARIUM, DIS- SOLVED (UG/L AS BA) S3 -- 54 -- 51 62 COBALT, DIS- SOLVED (UG/L AS CO) <3 -. <3 -- <3 <3 IRON, DIS- SOLVED (UG/L AS FB) 11 -- <3 -- 4 10 LITHIUM DIS- SOLVED (UG/L AS LI) <4 -- S -- <4 <4 MANGA- NESE, DIS- SOLVED (UG/L AS MN) 60 — 24 -- 99 130 MOLYB- SBLB- STRON- DENUM, NICKEL, NIUM, SILVER, TIUM, DIS- DIS- DIS- DIS- DIS- SOLVED SOLVED SOLVED SOLVED SOLVED (UG/L (UG/L (UG/L (UG/L (UG/L AS MO) AS NI) AS SB) AS AG) AS SR) <10 <1 <1 <1.0 210 __ <10 3 <1 <1.0 270 __ <10 <1 <1 <1.0 220 <10 2 <1 <1.0 220 VANA- DIUM, DIS- SOLVED (UG/L AS V) <6 — <6 -- 10 <6 162 RIO DB LA PLATA BASIN 50046000 RIO DB LA PLATA AT HWY 2 NR TOA ALT A, PR—Continued (National •tream-quality accounting network station) WATER-QUALITY DATA, WATER YBAR OCTOBER 1990 TO SEPTEMBER 1991 PARTICLB-SIZB DISTRIBUTION OF SUSPENDED SEDIMENT DATS OCT 1991 02... DEC 1992 17... FBB 21... APR 14... JUN 29... AUG 17.. . TIME 1000 1045 0915 0910 0930 1055 STREAM- FLOW, INSTAN- TANEOUS (CFS) 30 24 11 14 20 31 SEDI- MENT, SUS- PENDED (M6/L) 32.7 113 61.8 68 17 28 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 2.65 7.32 1.84 2.57 0.92 2.34 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 92 64 90 91 96 100 PESTICIDE ANALYSES DATE JUN 1992 29... TIME 0930 PCB, TOTAL (UG/L) ALDRIN, TOTAL (UG/L) <0.010 CHLOR- DANB, TOTAL (UG/L) DDD, TOTAL (UG/L) DDB, TOTAL (UG/L) DOT, TOTAL (UG/L) DI- AZINON, TOTAL (UG/L) DI- BNDO- <0.010 <0.010 <0.010 BLDRIN SULFAN, TOTAL TOTAL (UG/L) (UG/L) <0.01 <0.010 <0.010 ENDRIN WATER HBPTA- UNFLTRD BTHION, CHLOR, DATE REC TOTAL TOTAL (UG/L) (UG/L) (UG/L) JUN 1992 29... <0.010 HBPTA- CHLOR BPOXIDB LINDANE TOTAL TOTAL (UG/L) (UG/L) <0.01 <0.010 <0.010 <0.010 MALA- THION, TOTAL (UG/L) <0.01 MBTH- OXY- CHLOR, TOTAL (UG/L) <0.01 METHYL PARA- THION, TOTAL (UG/L) <0.01 MIRBX, TOTAL (UQ/L) <0.01 DATS JUN 1992 29... PARA- THION, TOTAL (UG/L) NAPH- THA- LENES, POLY- CHLOR. TOTAL (UG/L) PBR- THANB TOTAL (UG/L) TOX- APHBNB, TOTAL (UG/L) TOTAL TRI- THION (UG/L) 2,4-D, TOTAL (UG/L) 2,4, 5-T TOTAL (UG/L) 2, 4 -DP TOTAL (UG/L) SILVEX, TOTAL (UG/L) <0.01 <0.10 <1 <0.01 <0.01 <0.01 <0.01 <0.01 763 S&N JUAN EXPLANATION A 047560 SURFACE-WATER STATION AND NUMBER T 0476 QUALITY-OF-WATER STATION AND NUMBER • 220 WELL AND WELL NUMBER • 047550 LAKE-ELEVATION STATION Figure 19.~Rio Hondo to Rio Puerto Nuevo basins. 164 v^ RIO HONDO BASIN 50047530 RIO HONDO AT FLOOD CHANNEL NEAR CATANO, PR HATER-QUALITY RECORDS LOCATION.—Lat 18°26'13", long 66°09'36", at Rio Hondo Channel, 800 ft (245 •) below junction with Rio Hondo, 0.9 mi (1.5 km) downstream from bridge on de Diego Expressway and 1.1 mi (1.8 km) above mouth. DRAINAGE ARBA.--Indeterminate. PERIOD OP RECORD.—Hater years 1979 to current year. WATER-QUALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE NOV 1991 01... JAN 1992 0 2 ... MAR 02... MAY 22... JXJL 10... TIME 0805 0810 1030 0845 1005 DIS- CHARGE, INST. CUBIC FEET PER SECOND 25 -- -- 34 -- SPE- CIFIC CON- DUCT- ANCE (US/CM) 3900 17000 35600 1300 9900 PH HATER WHOLE FIELD (STAND- ARD UNITS) 7.6 7.5 7.9 7.1 7.6 TEMPER- ATURE HATER (DBG C) 24.5 23.0 27.5 27.0 30.0 TUR- BID- ITY (NTU) 24 3.1 4.5 27 6.2 OXYGEN, DIS- SOLVED (MG/L) 4.7 4.4 8.0 2.5 6.0 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 34 30 68 32 47 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 24 250 620 68 120 COLI- FORM, FBCAL, 0.45 DM-MF (COLS./ 100 ML) 32000 59000 26000 82000 27000 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 47000 31000 4900 35000 8900 DATE NOV 1991 01... JAN 1992 02... MAR 02... MAY 22... JUL 10... HARD- NESS TOTAL (MG/L AS 260 440 HARD- NESS NONCARB CALCIUM WH HAT TOT FLD CACO3) CACO3 170 300 DIS- SOLVED MG/L AS (MG/L 44 59 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS NA) 37 72 300 540 SODIUM AD- SORP- TION RATIO 14 ALKA- POTAS- LINITY CHLO- SIUM, HAT WH SULFATB RIDE, DIS- TOT FET SULFIDB DIS- DIS- SOLVED FIELD TOTAL SOLVED SOLVED (MG/L MG/L AS (MG/L (MG/L (MG/L AS K) 15 28 CACO3 AS S) AS S04) AS CL) <0.5 100 200 150 140 <0.5 140 87 170 520 980 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- DATE NOV 1991 01.. . JAN 1992 02... MAR 02... MAY 22... JUL 10... RIDE, DIS- CONSTI- DIS- AT 105 DIS- SOLVED TUENTS, SOLVED DBG. C. SOLVED (MG/L DIS- (TONS SDS- (MG/L AS SOLVED PER PENDBD AS F) SI02) (MG/L) DAY) (MG/L) 0.10 8.8 1070 72 28 19 30 0.30 12 1960 180 18 26 GEN, NITRATE TOTAL (MG/L AS 0 0 0 0 N) .410 .090 .100 .500 -- GBN, NITRITE TOTAL (MG/L AS 0. 0. 0. 0. 0. N) 060 070 090 070 020 GEN, N02+N03 TOTAL (MG/L AS 0 0 0 0 <0 N) .470 .160 .190 .570 .050 GBN, AMMONIA TOTAL (MG/L AS 0. 2. 1. 0. 0. N) 340 00 20 220 400 GEN, ORGANIC TOTAL (MG/L AS 0 0 0 0 0 N) .76 .50 .0 .58 .80 RIO HONDO BASIN 50047530 RIO HONDO AT FLOOD CHANNEL NEAR CATANO, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 165 DATE NOV 1991 01.. . JAN 1992 02... MAR 02... MAY 22... JUL 10... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 1.1 2.5 1.2 0.80 1.2 NITRO- GEN, TOTAL (MG/L AS N) 1.6 2.7 1.4 1.4 -- NITRO- GEN, TOTAL (MG/L AS N03) 6.9 12 6.2 6.1 -- PHOS- PHORUS TOTAL (MG/L AS P) 0.330 0.660 0.410 0.220 0.500 ARSENIC TOTAL (UG/L AS AS) 7 -- -- 4 -- BARIUM, TOTAL RECOV- ERABLE (UQ/L AS BA) 80 -- -- 100 -- BORON, TOTAL RECOV- ERABLE (UQ/L A3 B) 120 -- -- 220 -- CADMIUM TOTAL RECOV- ERABLE (UQ/L AS CD) <1 -- -- 1 -- CHRO- MIUM, TOTAL RECOV- ERABLE (UO/L A3 CR) <1 -- -- 3 -- COPPER, TOTAL RECOV- ERABLE (UO/L AS CU) 12 -- — 10 — DATE NOV 1991 01... JAN 1992 02.. . MAR 02... MAY 22... JUL 10... IRON, TOTAL RECOV- ERABLE (UQ/L AS KB) LEAD, TOTAL RECOV- ERABLE (UQ/L AS PB) MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) SELE- NIUM, TOTAL (UG/L AS SB) SILVER, TOTAL RECOV- ERABLE (UQ/L AS AG) ZINC, TOTAL RECOV- ERABLE (UQ/L AS ZN) CYANIDE TOTAL (MG/L AS CN) PHENOLS TOTAL (UQ/L) MBTHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 1500 640 150 130 0.20 0.10 <1 <1 <1 <1 13 20 <0.010 <0.010 0.12 0.49 766 RIO DB BAYAMON BASIN 50047550 LAGO CIDRA AT DAMSITB NEAR CIDRA, PR LOCATION.--Lat 18°11'57", long 66°08'29", Hydrologic Unit 21010005, at Lago de Cidra Dam on Rio de Bayamon, 1.9 ml (3.0 km) northeast of Plaza de Cldra and 1.8 mi (2.9 km) northwest of Bscuela Segunda Unidad de Bayam6n. DRAINAGE AREA.--8.26 mi 2 (21.39 km2 ). ELEVATION RECORDS PERIOD OF RECORD.—January 1988 to current year. GAGE.—Water-stage recorder. Datum of gage is mean sea level. REMARKS.—Lago de Cidra was completed in 1946. The maximum storage is 5,300 ac-ft (6.53 hn?) and provides supple- mental water to metropolitan San Juan. The dam is a concrete gravity and earthfill structure approximately 541 ft (165 m) long between abutments with a maximum structural height of about 78.7 ft (24.0 m). The spillway portion of the dam, length 131 ft (40 m) and crest elevation 1,322 ft (403 m), is an ungated ogee crest located 131 ft (40 m) from the right abutment. This dam is owned by Puerto Rico Aqueduct and Sewer Authority. Gage-height and precipitation satellite telemetry at station. EXTREMES OBSERVED FOR PERIOD OF RECORD.--Maximum elevation 1,323.99 ft (403.55 m), Feb. 3, 1988; minimum elevation 1,305.18 ft (397.82 m), Sept. 30, 1990. EXTREMES OBSERVED FOR CURRENT YEAR.--Maximum elevation, 1,322.29 ft (403.03 m), Jan. 14; minimum elevation, 1,311.00 ft (399.59 m), Sept. 19. Capacity Table (based on data from Puerto Rico Electric Power Authority) Elevation, in feet 1,305 1,309 1,312 Contents, in acre-feet 1,970 2,610 3,100 Elevation, in feet 1,319 1,322 1,324 Contents, in acre-feet 4,400 5,200 5,800 ELEVATION (FEET NGVD), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY OBSERVATION AT 24!00 VALUES DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN MAX MIN NOV DEC JAN FBB MAR APR MAY JUN JUL SEP 1311.73 1311.92 1312.08 1312.16 1312.21 1312.27 1312.31 A A A A A A A A 1312.28 1312.23 1312.19 1312.17 1312.10 1312.00 1311.94 1311.84 1311.78 1311.74 1311.68 1311.61 1311.43 1311.31 1311.38 1311.36 ___ 1311.40 1311.33 1311.32 1311.21 1311.15 1311.13 1311.81 A A A A A A A A A A A A A A A A A 1312.93 1313.12 1313.33 A A A ___ ___ —— A A A A A A A A A A A 1314.56 1314.81 1314.67 1314.56 1314.63 1314.72 1314.78 1314.84 1315.08 1315.17 1315.27 A A A A A A 1315.07 1314.89 1314.73 ___ ___ 1314.51 1314.37 1314.21 1314.04 A A A A A A A A A 1322.22 1322.02 1321.92 1321.89 1321.84 1321.79 1321.74 1321.66 1321.56 1321.46 1321.37 1321.36 1321.35 1321.32 1321.32 1321.40 1321.45 1321.50 ___ 1321.49 1321.31 1321.12 1321.05 1321.01 1320.99 1320.96 1320.92 1320.89 1320.88 1320.85 1320.81 1320.77 1320.73 1320.66 1320.62 1320.58 1320.52 1320.47 1320.43 1320.36 1320.39 1320.43 1320.36 1320.25 1320.22 1320.15 1320.07 1319.95 ___ --- 1320.66 1321.49 1319.95 1319.83 1319.66 1319.53 1319.41 1319.29 1319.16 1319.05 1318.92 1318.78 1318.67 1318.59 1318.51 1318.40 1318.33 1318.26 1318.21 1318.18 1318.14 1318.17 1318.04 1317.87 1317.72 1317.58 1317.42 1317.25 1317.09 1316.93 1316.90 1316.75 1316.60 1316.47 1318.18 1319.83 1316.47 1316.36 1316.51 1316.40 1316.28 1316.15 1315.98 1315.78 1315.62 1315.45 1315.27 1315.15 1315.07 1315.05 1315.03 1315.01 1314.95 1314.89 1314.81 1314.89 1314.85 1314.78 1314.74 1314.61 1314.39 1314.15 1313.92 1313.70 1313.60 1313.50 1313.46 —— 1315.01 1316.51 1313.46 1313.46 1313.51 1313.54 1313.50 1313.43 1313.38 1313.29 1313.21 1313.15 1313.09 1313.01 1312.97 1312.96 1312.95 1312.96 1312.98 1313.01 1312.99 1312.96 1312.95 1313.35 1313.42 1314.25 1314.92 1315.35 1315.83 1315.99 1316.09 1316.19 1316.30 1316.37 1313.91 1316.37 1312.95 1316.44 1316.45 1316.48 1316.54 1316.52 1316.41 1316.35 1316.45 1316.54 1316.76 1316.98 1317.18 1317.37 1317.52 1317.59 1317.67 1317.76 1317.85 1317.86 1317.78 1317.90 1317.99 1317.92 1317.91 1317.95 1317.89 1317.81 1317.64 1317.54 1317.43 1317.28 1317.99 1316.35 1317.34 1317.40 1317.43 1317.38 1317.36 1317.33 1317.32 1317.33 1317.29 1317.20 1317.14 1317.01 1316.97 1316.90 1316.84 1316.93 1316.97 1316.87 1316.80 1316.72 1316.61 1316.54 1316.58 1316.68 1316.64 1316.60 1316.55 1316.32 1316.03 1315.78 1315.60 1316.85 1317.43 1315.60 1315.44 1315.37 1315.27 1315.25 1315.76 1316.34 1316.51 1316.53 1316.50 1316.41 1316.22 1316.11 1316.01 1315.92 1315.83 1315.67 1315.45 1315.30 1315.20 1315.09 1314.94 1314.77 1314.61 1314.41 1314.19 1314.05 1313.91 1313.74 1313.50 1313.31 1313.17 1315.19 1316.53 1313.17 1312.92 1312.68 1312.48 1312.32 1312.30 1312.30 1312.17 1312.06 1312.09 1311.96 1311.82 1311.67 1311.49 1311.31 1311.15 1311.09 1311.12 1311.07 1311.27 1311.99 1312.75 1313.11 1313.44 1313.67 1313.83 1313.88 1313.85 1313.83 1313.86 1313.90 --- 1312.45 1313.90 1311.07 A No gage-height record. 167 RIO DB BAYAMON BASIN 50047560 RIO DB BAYAMON BELOW LAOO CIDRA, PR LOCATION.—Lat 18°12'04", long 66"08'26', Hydrologic Unit 21010005, 0.2 Mi (0.3 km) downstream of Lago Cidra Dam on right bank, 2.1 mi (3.4 km) northwest of Plaza de Cidra. DRAINAGE ARBA.--8.31 mi* (21.5km'). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—November 1990 to current year. GAGE.—Water-stage recorder. Elevation of gage is 1,279 ft (390 m), from topographic map. REMARKS.—Records poor. Regulation at all stages by Puerto Rico Aqueduct and Sewer Authority reservoir upstream from gage. Gage-height and precipitation satellite telemetry at station. DAY DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES OCT NOV DBC JAN FBB MAR APR MAY JUN JUL ADO SEP 1 22 32 2 23 32 3 24 32 4 23 33 5 24 21 6 23 4.7 7 31 9.8 8 17 8.7 9 17 5.6 10 17 6.2 11 18 7.6 12 18 9.5 13 18 85 14 18 119 15 18 128 16 18 125 17 18 122 18 18 111 19 19 104 20 20 82 21 19 85 22 19 42 23 12 3.0 24 2.5 4.0 25 2.9 3.4 26 2.7 3.4 27 7.7 3.9 28 61 4.1 29 43 4.0 30 33 4.0 31 29 --- TOTAL 635.8 1234.9 MEAN 20.5 41.2 MAX 61 128 MIN 2.5 3.0 AC-FT 1260 2450 CFSM 2.47 4.95 IN. 2.84 5.52 e Estimated 4.3 103 36 7.5 7.6 7.5 7.6 7.8 7.9 7.9 8.2 8.5 64 116 88 3.6 3.5 3.6 3.6 5.1 .1 .2 .4 .1 .7 3.7 21 106 100 97 91 941.4 30.4 116 3.5 1870 3.65 4.21 STATISTICS OF MONTHLY MEAN DATA MEAN 20.5 40.8 MAX 20.5 41.2 (WY) 1992 1992 MIN 20.5 40.5 (WY) 1992 1991 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 21.4 30.4 1992 12.4 1991 FOR 84 74 63 77 154 981 119 23 12 24 12 9.2 9.8 22 41 30 12 7.1 7.0 7.1 12 13 13 e21 e2.7 e3.3 e2.6 e2.9 e2.7 e2.6 e2.6 1846.6 59.6 981 2.6 3660 7.16 8.26 e27 41 28 22 19 19 19 20 20 21 21 21 21 22 22 23 23 24 24 25 e24 e3.6 ell 40 32 27 26 26 26 --- 677.6 23.4 41 3.6 1340 2.81 3.03 FOR WATER YEARS 1991 37.3 59.6 1992 14.9 1991 29.8 36.5 1991 23.4 1992 28 35 29 27 26 26 26 26 27 22 16 16 15 16 15 15 15 15 elO 27 38 34 27 27 27 26 26 26 26 26 21 736 23.7 38 10 1460 2.85 3.29 - 1992 18.5 23.7 1992 13.4 1991 1991 CALENDAR YEAR 7515.0 20.6 193 2.5 3.7 14910 2.47 33.60 37 13 8.4 Feb 6 Oct 24 Nov 23 19 20 19 19 18 27 35 30 28 28 29 28 24 21 21 24 17 17 28 27 22 10 19 31 31 30 30 16 14 7.2 —— 689.2 23.0 35 7.2 1370 2.76 3.08 7.5 7.8 7.6 7.6 7.5 11 24 21 9.3 9.6 9.6 9.3 9.1 9.6 9.5 12 27 16 14 11 12 10 15 e9.0 e3,8 e4.4 e4.1 e4.4 e4.4 e3.8 e4.4 315.3 10.2 27 3.8 625 1.22 1.41 e!2 17 e9.9 e6.8 e2S 37 31 8.6 8.3 8.7 8.2 8.2 8.0 7.8 7.6 7.5 7.2 6.6 28 36 17 11 35 14 16 27 34 34 23 34 534.4 17.8 37 6.6 1060 2.14 2.39 28 2.8 14 20 20 14 11 11 20 24 28 32 26 23 23 12 9.5 27 27 26 27 27 8.1 2.9 19 14 14 31 31 21 15 608.3 19.6 32 2.8 1210 2.36 2.72 9.2 1.9 1.8 1.8 5.6 .60 .65 .64 .72 12 28 6.3 6.3 6.8 7.0 17 28 15 4.5 4.7 12 15 15 23 26 14 13 40 40 24 16 396.51 12.8 40 .60 786 1.54 1.77 33 39 30 13 10 10 9.5 10 10 9.8 9.6 9.6 18 24 11 12 11 15 22 11 5.4 1.9 1.6 1.6 11 25 32 18 7.9 8.1 —— 430.0 14.3 39 1.6 853 1.72 1.92 , BY WATER YEAR (WY) 17.6 23.0 1992 12.2 1991 FOR 1992 9046. 24. 981 . 1. 1540 15. . 17940 2. 40. 36 17 4. 11.2 12.2 1991 10.2 1992 WATER YEAR 01 7 Jan 6 60 Aug 6 7 Aug 3 Jan 6 33 Jan 6 60 Aug 6 97 45 0 15.0 17.8 1992 12.1 1991 15.6 19.6 1992 11.7 1991 WATER 24 24 24 981 1 1540 15 17910 2 40 35 13 7 20.2 27.5 1991 12.8 1992 YEARS 1991 .7 .7 .7 Jan .60 Aug .7 Aug Jan .33 Jan .60 Aug .97 .36 .5 15.2 16.0 1991 14.3 1992 - 1992 1992 1992 6 1992 6 1992 3 1992 6 1992 6 1992 6 1992 RIO DB BAYAMON BASIN 50047560 RIO DB BAYAMON BELOW LAGO CIDRA, PR—Continued WATER-QUALITY RECORDS PBRIOD OF RECORDS.— Water years 1991 to current year. INSTRUMENTATION.-- DH-48 and automatic sediment sampler. PBRIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGEi November 1990 to September 1992 EXTREMES FOR PBRIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATIONt Maximum daily 6 mg/L Sep. 01, 1991. SEDIMENT LOADS: Maximum daily mean, 9,830tons (8,920tonnes) Jan. 05, 1992; Mini 0.04 ton (0.03 tonne) Aug 09-10, 1992. n, 3,670 mg/L Jan. 05, 1992; Minimum daily mean, daily mean, EXTREMES FOR WATER YEARS 1991-92.-- Water Year 1991 1992 Suspended-sediment concentration (mg/L) MTlmuai minimum Suspended-sediment discharge (tons per day) 778 (Feb. 12) 3,670 (Jan. 06) 6 (Sep. 01) 8 (Sep. 11) 338 (Feb. 05) 9,830 (Jan. 06) .19 (Sep. 10) .04 (Aug. 09-10) SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAY MEAN DISCHARGE (CFS) MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) OCTOBER MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) NOVEMBER 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL 13 12 13 28 28 28 26 28 28 29 29 29 52 60 60 62' e55 e55 e60 e60 e55 e60 e60 e60 e55 e55 e55 e35 e!3 e!2 1215 33 33 33 33 45 55 62 62 62 62 62 62 62 62 60 60 60 60 60 60 60 60 60 60 60 60 60 60 60 60 1.2 1.1 1.2 2.8 3.5 .2 ,4 ,7 ,7 ,9 .9 .9 8.7 10 9.7 10 e8.9 e8.9 e9.7 e9.7 e8.9 e9.7 e9.7 e9.7 e8.9 e8.9 e8.9 e5.7 e2.1 el.9 192.5 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) DECEMBER e!2 e!3 e!3 e!3 13 13 13 13 13 13 13 12 13 13 12 12 12 12 11 11 12 12 12 12 11 10 11 11 12 12 20 385 56 51 51 48 46 51 61 63 65 65 67 66 71 71 65 55 46 43 45 53 54 44 44 49 45 41 40 32 25 26 524 el.8 el.7 el.8 el.6 1.6 1.8 2.1 2.2 2.3 2.2 2.3 2.1 2.4 2.4 2.1 1.8 1.4 1.3 1.3 1.5 1.7 1.4 1.4 1.5 1.3 1.1 1.2 .90 .80 .79 42 91.79 e Estimated RIO DB BAYAMON BASIN 169 50047560 RIO DB BAYAMON BBLOW LAGO CIDRA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) JANUARY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL 12 20 18 16 16 16 16 18 19 19 18 17 15 15 16 15 15 14 14 12 12 12 12 12 13 13 13 13 14 14 14 463 189 109 77 54 44 43 41 34 22 12 8 9 10 13 18 20 18 14 13 13 11 11 13 15 17 18 18 19 25 33 39 -__ 5.9 6.3 3.7 2.3 1.8 1.8 1.8 1.5 1.1 .60 .40 .39 .37 .49 .74 .84 .69 .53 .46 .40 .35 .35 .40 .47 .58 .64 .61 .67 .93 1.3 1.4 39.81 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) FEBRUARY MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) 14 13 12 13 143 193 73 38 25 17 30 64 120 50 26 17 13 14 20 19 18 16 15 14 14 11 10 11 38 32 25 24 423 47 45 45 45 44 42 778 426 19 27 42 54 54 49 47 45 46 48 48 54 65 74 79 1.4 1.1 .82 .83 388 26 9.1 4.8 3.1 2.1 3.5 337 199 2.9 2.0 2.1 2.1 2.2 2.9 2.6 2.3 2.2 2.1 2.0 2.1 2.0 2.2 2.6 MARCH 1023 1011.05 12 13 13 17 16 17 18 19 19 14 11 11 11 11 12 12 12 13 13 13 13 14 13 13 13 12 12 12 12 11 12 414 75 64 54 50 48 44 36 23 11 10 10 14 21 27 34 38 38 35 33 34 39 40 38 32 24 16 11 23 48 61 53 2.5 2.3 2.0 2.2 2.2 2.1 1.8 1.2 .57 .38 .31 .41 .63 .81 1.1 1.2 1.2 1.2 1.1 1.1 1.4 1.3 1.3 1.1 .81 .50 .34 .73 1.5 1.8 1.7 38.79 770 RIO DB BAYAMON BASIN 50047560 RIO DB BAYAMON BELOW LAGO CIDRA, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 11 11 11 10 10 12 12 12 12 12 12 12 13 13 13 12 13 13 12 12 13 13 13 13 13 13 13 13 13 12 ___ APRIL 45 22 32 49 61 61 53 50 53 55 57 57 53 49 47 45 41 38 26 21 26 31 25 22 27 33 39 45 49 48 -__ 1.3 .61 .91 1.3 1.6 1.8 1.7 1.6 1.7 1.8 1.8 2.0 1.8 1.7 1.6 1.5 1.4 1.2 .85 .68 .92 1.1 .81 .74 .91 1.1 1.3 1.6 1.6 1.5 ___ MAY 13 13 13 13 13 13 14 14 13 11 11 11 11 11 11 11 12 12 11 12 11 12 12 12 15 12 11 12 13 12 12 34 20 20 21 29 29 26 22 19 17 15 14 13 12 11 11 10 10 10 10 15 25 40 55 48 35 23 20 25 29 27 1.1 .70 .68 .68 .99 .98 .92 .78 .59 .50 .44 .37 .37 .34 .32 .31 .30 .33 .28 .32 .43 .75 1.3 1.8 2.0 1.1 .69 .61 .79 .94 .86 MEAN DISCHARGE (CFS) 13 13 13 13 13 13 12 12 12 12 12 12 13 13 12 12 11 12 12 12 12 12 12 12 12 11 11 11 12 12 MEAN CONCEN- TRATION (MG/L) JUNE 22 18 18 20 20 25 54 70 54 37 24 26 38 46 47 46 43 31 22 21 20 19 17 57 57 81 76 49 25 15 SEDIMENT DISCHARGE (TONS/DAY) .69 .56 .59 .67 .67 .84 1.7 2.1 1.7 1.2 .77 .82 1.2 1.6 1.5 1.4 1.3 .92 .64 .67 .61 .60 .55 1.7 1.7 2.4 2.3 1.4 .76 .45 TOTAL 367 40.43 377 22.57 364 34.01 RIO DB BAYAMON BASIN 50047560 RIO DB BAYAMON BELOW LAGO CIDRA, PR- -Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 777 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CPS) MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) JULY 11 11 11 11 11 11 11 11 11 11 11 11 10 11 14 21 9.4 9.5 10 11 11 11 11 11 11 12 14 13 14 13 13 14 13 12 12 12 13 13 13 14 16 16 16 14 12 21 103 41 43 39 35 30 26 22 19 17 15 15 16 16 17 18 .42 .39 .36 .36 .37 .37 .37 .37 .40 .46 .46 .46 .36 .34 1.0 27 .97 1.1 1.1 .99 .89 .80 .66 .57 .52 .52 .56 .56 .56 .62 .65 MEAN DISCHARGE (CPS) 14 14 15 16 15 16 16 17 16 17 17 19 30 49 49 41 23 18 47 45 46 55 43 37 37 28 24 20 29 26 14 MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) AUGUST 19 21 28 35 40 39 34 30 33 38 41 38 31 25 37 30 30 28 22 18 17 27 25 18 18 17 13 15 7 5 5 .70 .75 1.1 1.6 1.6 1.6 1.4 1.3 1.4 1.7 1.9 1.9 2.6 3.3 4.6 3.3 2.0 1.3 2.8 2.2 2.1 4.6 2.9 1.8 1.8 1.4 .84 .81 .52 .37 .20 MEAN DISCHARGE (CPS) 13 14 13 13 12 12 11 12 12 12 12 32 23 11 12 12 26 14 15 15 16 17 17 18 18 18 19 20 20 21 MEAN CONCEN- TRATION (MG/L) SEPTEMBER 6 7 8 7 7 7 6 7 7 6 7 20 18 11 11 13 373 49 34 31 22 14 11 14 16 17 19 20 20 20 SEDIMENT DISCHARGE (TONS/ DAY) .22 .26 .27 .27 .26 .23 .20 .21 .21 .19 .22 2.3 1.3 .31 .32 .43 164 1.9 1.4 1.2 .97 .67 .52 .63 .71 .79 .95 1.0 1.0 1.2 TOTAL 361.9 44.56 853 56.39 480 184.14 772 RIO DB BAYAMON BASIN 50047560 RIO DB BAYAMON BELOW LAGO CIDRA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) OCTOBER 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL 22 23 24 23 24 23 31 17 17 17 18 18 18 18 18 18 18 18 19 20 19 19 12 2.5 2.9 2.7 7.7 61 43 33 29 635.8 29 28 28 27 26 26 232 31 25 26 27 29 30 30 30 30 30 30 29 27 24 25 30 37 40 38 35 35 35 272 30 .._ 1.6 1.7 1.8 1.6 1.7 1.6 82 1.4 1.1 1.1 1.2 1.3 1.3 1. 1. 1. 1. 1. 1.5 1.4 1.2 1.3 .98 .26 .32 .31 .67 5.7 3.8 44 2.3 170.14 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) NOVEMBER 32 32 32 33 21 4.7 9.8 8.7 5.6 6.2 7.6 9.5 85 119 128 125 122 111 104 82 85 42 3.0 4.0 3.4 3.4 3.9 4.1 4.0 4.0 1234.9 22 22 22 22 25 20 29 28 28 28 31 32 38 40 42 45 100 52 50 44 39 37 38 47 51 56 59 55 44 40 1 1 1 1 1 8 13 14 15 32 15 14 10 8 3 .8 .8 .8 .9 .3 .23 .98 .68 .43 .46 .63 .93 .2 .8 .9 .30 .53 .44 .51 .57 .55 .46 .42 DECEMBER 150.62 4.3 103 36 7.5 7.6 7.5 7.6 7.8 7.9 7.9 8.2 8.5 64 116 88 3.6 3.5 3.6 3.6 5.1 3.7 21 106 100 97 91 941.4 30 28 30 39 40 40 38 32 29 28 30 30 49 20 20 20 20 25 27 26 34 59 72 61 50 50 53 56 55 53 51 .33 7.6 2.8 .76 .82 .80 .79 .66 .62 .59 .66 .70 12 6.2 4.8 .20 .19 .23 .23 .33 .39 .62 .88 .68 .60 .51 2.9 16 15 14 12 104.89 RIO DB BAYAMON BASIN 50047560 RIO DB BAYAMON BELOW LAGO CIDRA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) 173 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN DISCHARGE (CPS) 84 74 63 77 154 981 119 23 12 24 12 9.2 9.8 22 41 30 12 7.1 7.0 7.1 12 13 13 e21 e2.7 e3.3 e2.6 e2.9 e2.7 e2.6 e2.6 1846.6 MEAN CONCEN- TRATION (MG/L) JANUARY 49 50 52 51 1170 3670 1140 111 102 94 92 91 90 91 135 183 184 177 173 166 156 149 146 145 145 148 151 151 134 113 107 SEDIMENT DISCHARGE (TONS/ DAY) 11 9.7 8.8 10 976 9830 600 7.1 3.6 5.7 3.0 2.1 2.5 5.3 15 15 6.3 3.2 3.2 3.0 4.8 5.2 5.1 e8.6 el.l el. 3 el.l el. 2 e.98 e.79 e.75 11551.42 FEBRUARY e27 41 28 22 19 19 19 20 20 21 21 21 21 22 22 23 23 24 24 25 e24 e3.6 ell 40 32 27 26 26 26 677.6 102 100 98 92 84 83 92 104 107 96 80 67 62 62 62 62 61 60 63 68 70 75 76 77 71 68 64 63 64 e7.1 10 7.2 5.7 4.3 4.2 4.7 5.5 5.8 5.3 4.4 3.6 3.4 3.5 3.6 3.7 3.8 3.8 4.0 4.5 e4.6 e.68 e2.5 8.4 5.8 4.9 4.5 4.3 4.4 MEAN DISCHARGE (CFS) 28 35 29 27 26 26 26 26 27 22 16 16 15 16 15 15 15 15 elO 27 38 34 27 27 27 26 26 26 26 26 21 MEAN CONCEN- TRATION (MG/L) MARCH 63 61 58 53 53 58 61 60 54 48 47 47 45 48 53 58 55 49 45 53 83 97 79 63 49 41 39 36 38 41 44 SEDIMENT DISCHARGE (TONS/ DAY) 4.6 5.8 4.8 3.7 3.7 4.0 4.3 4.2 3.8 2.7 2.0 1.9 1.8 1.9 2.1 2.3 2.2 2.1 el. 2 3.7 8.3 8.3 5.7 4.4 3.4 2.9 2.7 2.5 2.6 2.9 2.6 138.18 736 109.1 e Estimated 174 RIO DB BAYAMON BASIN 50047560 RIO DB BAYAMON BELOW LAGO CIDRA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCKN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 19 20 19 19 18 27 35 30 28 28 29 28 24 21 21 24 17 17 28 27 22 10 19 31 31 30 30 16 14 7.2 --- APRIL 46 46 46 45 45 43 42 41 43 53 67 75 71 60 51 45 41 40 40 41 42 44 42 40 40 30 34 36 44 53 -__ MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MEAN MEAN CONCKN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MAY 2.2 2.5 2.3 2.3 2.2 3.3 3.9 3.4 3.2 4.0 5.2 5.8 4.6 3.3 2.8 2.7 1.9 1.8 2.8 2.9 2.4 1.2 2.1 3.3 3.2 2.4 2.7 1.6 1.7 1.0 --- 7 7 7 7 7 11 24 21 9 9 9 9 9 9 9 12 27 16 14 11 12 10 15 e9 e3 e4 e4 e4 e4 e3 e4 .5 .8 .6 .6 .5 .3 .6 .6 .3 .1 .6 .5 .0 .8 .4 .1 .4 .4 .8 .4 63 68 62 49 41 43 50 57 52 45 40 39 40 42 46 52 59 61 70 62 46 30 38 63 117 108 71 62 60 61 60 1.3 1.4 1.2 .94 .78 1.3 3.2 3.3 1.3 1.1 .97 .96 .99 1.0 1.2 1.6 4.5 2.8 2.9 1.7 1.6 .82 1.6 el. 5 el. 2 el. 3 e.78 e.73 e.72 e.63 e.71 e!2 17 e9. e6. e25 37 31 8. 8. 8. 8. 8. 8. 7. 7. 7. 7. 6. 28 36 17 11 35 14 16 27 34 34 23 34 -- JDNB 9 8 6 3 7 2 2 0 8 6 5 2 6 - 52 43 32 26 21 20 18 19 20 27 45 75 73 63 52 42 33 33 32 30 31 31 29 29 26 23 21 18 15 15 --- el. 6 2.0 e.86 e.43 el. 4 1.9 1.5 .42 .44 .66 .94 1.6 1.5 1.3 .99 .87 .65 .54 2.3 2.9 1.4 .97 2.7 1.1 1.1 1.7 1.9 1.6 1.0 1.3 ___ TOTAL 689.2 84.7 315.3 46.03 534.4 39.57 e Estimated RIO DB BAYAMON BASIN 50047560 RIO DB BAYAMON BELOW LAGO CIDRA, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 775 MEAN DISCHARGE DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL YEAR (CFS) 28 2 14 20 20 14 11 11 20 24 28 32 26 23 23 12 9 27 27 26 27 27 8 2 19 14 14 31 31 21 15 608 9046. .8 .5 .1 .9 .3 01 MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) JULY 15 15 15 14 14 13 12 12 16 16 16 14 12 12 12 14 31 50 59 51 37 26 19 14 11 8 7 4 5 6 6 1.1 .11 .58 .76 .74 .54 .34 .35 .86 .98 1.1 1.2 .86 .72 .72 .41 .87 3.6 4.1 3.6 2.6 1.8 .50 .09 .60 .28 .26 .31 .39 .34 .23 MEAN MEAN CONCKN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AUGUST 9. 1. 1. 1. 5. 12 28 6. 6. 6. 7. 17 28 15 4. 4. 12 15 15 23 26 14 13 40 40 24 16 2 9 8 8 6 60 65 64 72 3 3 8 0 5 7 31 94 94 42 36 35 29 25 21 21 22 23 23 20 20 18 17 16 18 18 18 18 18 15 13 10 9 9 10 10 18 .57 .45 .43 .20 .56 .05 .05 .04 .04 .62 1.7 .38 .36 .36 .37 .84 1.2 .68 .22 .22 .56 .68 .68 .85 .82 .41 .28 .95 1.1 .68 .73 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) SEPTEMBER 30.94 12476.14 396.51 17.08 33 39 30 13 10 10 9.5 10 10 9.8 9.6 9.6 18 24 11 12 11 15 22 11 5.4 1.9 1.6 1.6 11 25 32 18 7.9 8.1 430.0 32 38 36 28 20 30 47 47 12 9 8 9 9 9 9 10 10 29 45 37 47 45 45 40 38 35 32 28 25 25 2.8 3.9 3.1 1.1 .53 .76 1.1 1.3 .37 .23 .21 .23 .41 .57 .25 .31 .30 1.5 3.3 1.3 .68 .22 .20 .18 1.1 2.3 2.8 1.4 .50 .52 33.47 176 RIO OB BAYAMON BASIN 50047560 RIO OB BAYAMON BELOW LAGO CIORA PR--Continued WATER QUALITY DATA, WATER YEARS JANUARY 1991 TO SEPTEMBER 1992 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT DATE JAN 1991 04... 13. .. FEB 05. .. JUL 16. .. SEP 17. .. OCT 07. .. 30. .. TIME 1753 1730 1640 0750 0859 1640 1500 DIS- CHARGE, INST. CUBIC FEET PER SECOND 15 14 310 78 238 215 93 SEDI- MENT, SUS- PENDED (MG/L) 2930 405 7700 1530 7370 4990 5080 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 119 15 64500 322 4730 2900 1280 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM 38 62 35 55 37 49 -- SBD. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM 46 -- 54 59 52 61 13 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 51 75 65 67 63 67 15 DATE JAN 1991 04.. . 13 .... FBB 05.. . JUL 16... SEP 17.. . OCT 07. .. 30. . . SBD. SUSP. FALL DIAM. PERCENT FINER THAN .016 MM 64 -- 73 77 71 76 -- SED. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM 75 85 81 80 78 86 17 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 96 95 94 99 98 99 25 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 99 97 98 99.2 99.4 99.5 25 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 99.5 98 99.4 99.5 99.6 99.7 99 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 100 99 99.6 99.7 99.7 100 100 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 100 99 99.8 100 100 100 100 RIO DB BAYAMON BASIN 50047560 RIO DB BAYAMON BELOW LAGO CIDRA , PR--Continu«d WATER QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT 177 DATE OCT 1991 04. . . 07.. . 30.. . NOV 21.. . 21.. . DEC 13. .. JAN 1992 07.. . 28. . . MAY 16.. . SEP 17.. . TIME 1520 1800 1400 1606 1846 1215 1605 1722 1505 1420 STREAM- PLOW, INSTAN- TANEOUS (CPS) 12 60 276 100 113 120 26 6 16 10 SEDI- MENT, SUS- PENDED (MG/L) 389 330 2320 53 197 118 130 156 423 725 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 13 53 1730 14 60 38 9 3 18 20 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 87 99 99 95 97 84 90 92 58 96 178 RIO DB BAYAMON BASIN 50047600 RIO DB BAYAMON NEAR AQUAS BUBNAS, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°14'39-, long 66°08'39", at bridge on Highway 156, and 2.9 mi (4.7 plaza. DRAINAGE AREA.--18.5 mi 1 (47.9 km 1 ). PERIOD OF RECORD.--Water years 1958-65, 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 km) west of Aguas Buenaa DATS OCT 1991 15. .. DSC 11. .. FEE 1992 24. .. APR 20. . . JUN 10. .. ADG 06. . . TIME 1430 1100 1315 1120 1145 0940 DIS- CHARGS, INST. CUBIC FSBT PER SECOND 17 11 49 36 20 30 SPB- CIFIC CON- DUCT - ANCB (US/CM) 297 329 233 218 295 213 PH WATER WHOLE FIELD (STAND- ARD UNITS) 8.2 8.0 7.9 7.1 8.1 6.9 TEMPER- ATURE WATSR (DSG C) 25.5 21.0 22.0 23.0 25.0 23.0 TUR- BID- ITY (NTU) 3.0 1.7 25 180 7.9 200 OXYGEN, DIS- SOLVED (MG/L) 8.5 6.5 8.3 7.3 8.1 6.9 OXYGEN, DIS- SOLVED (PBR- CENT SATUR- ATION) 106 79 101 86 99 83 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 16 11 10 27 <10 31 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 340 K10 6000 54000 490 1300 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 410 330 17000 53000 K1300 130000 DATE OCT 1991 15. .. DEC 11. .. FBB 1992 24.. . APR 20.. . JUN 10... AUG 06. . . HARD- NESS CALCIUM TOTAL DIS- (MG/L SOLVED AS (MG/L MAGNE- SIUM, DIS- SODIUM, DIS- SOLVED SOLVED (MG/L (MG/L CAC03) AS CA) AS MG) AS NA) 110 26 140 37 77 18 11 17 12 29 7.8 10 SODIUM AD- SORP- TION RATIO POTAS- SIUM, DIS- SOLVED (MG/L AS K) 0.7 2.3 3.2 0.5 3.1 ALKA- LINITY WAT WH TOT PET SULFIDB FIELD TOTAL MG/L AS (MG/L CAC03 110 130 120 140 110 59 CHLO- SULFATB RIDE, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS S) AS SO4) AS CL) <0.5 12 <0.5 25 17 20 32 24 DATE OCT 1991 15.. . DEC 11. .. FBB 1992 24.. . APR 20.. . JUN 10.. . AUG 06. .. FLUO- RIDE, DIS- SOLVED (MG/L AS F) 0.10 -- -- 0.20 -- •cO.10 SILICA, DIS- SOLVED (MG/L AS SIO2) 27 -- -- 15 -- 19 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 181 -- -- 236 -- 134 SOLIDS, DIS- SOLVED (TONS PER DAY) 8.47 -- -- 22.6 -- 10.9 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) <1 10 23 229 <1 232 NITRO- GEN, NITRATE TOTAL (MG/L AS N) -- -- 0.270 0.730 -- 1.58 NITRO- GEN, NITRITE TOTAL (MG/L AS N) <0.010 •cO.010 0.020 0.030 •cO.010 0.020 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 0.360 0.620 0.290 0.760 0.300 1.60 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.020 0.010 0.030 0.050 0.010 0.040 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.18 0.19 0.27 0.65 0.19 0.76 non-ideal count RIO DB BAYAMON BASIN 50047600 RIO DB BAYAMON NEAR AGUAS BUBNAS, PR—Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 179 DATE OCT 1991 15.. . DEC 11.. . FEB 1992 24.. . APR 20... JUN 10.. . AUG 06.. . DATE OCT 1991 15.. . DEC 11.. . FEB 1992 24.. . APR 20.. . JUN 10. .. AUG 06.. . NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.20 0.20 0.30 0.70 0.20 0.80 IRON, TOTAL RECOV- ERABLE (UG/L AS FE) 390 -- -- 13000 -- -- NITRO- GEN, TOTAL (MG/L AS N) 0.56 0.82 0.59 1.5 0.50 2.4 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) 3 -- — 5 -- -- NITRO- GEN, TOTAL (MG/L AS N03) 2.5 3.6 2.6 6.5 2.2 11 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) 30 -- -_ 330 -- -- PHOS- PHORUS TOTAL (MG/L AS P) 0.050 0.050 0.060 0.100 0.020 0.170 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) <0.10 -- — <0.10 -- -- BARIUM. TOTAL ARSENIC RBCOV- TOTAL ERABLB (UG/L (UG/L AS AS) AS BA) <1 <100 __ __ <1 <100 __ — — — — SILVER, SELE- TOTAL NIUM, RBCOV- TOTAL ERABLB (UG/L (UG/L AS SB) AS AG) <1 <1 __ __ <1 <1 __ __ BORON, TOTAL RECOV- ERABLE (UG/L AS B) 60 -- -- 60 -- — — ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) 20 -- -- 30 -- -- CHRO- CADMIUM MIUM, TOTAL TOTAL RBCOV- RECOV- ERABLE BRABLB (UG/L (UG/L AS CD) AS CR) <1 2 __ __ <1 13 __ — — — — CYANIDE TOTAL PHENOLS (MG/L TOTAL AS CN) (UG/L) •cO.010 1 __ — <0.010 1 __ __ COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) <10 — -- 40 — — — MBTHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 0.03 — -- 0.01 -- -- 180 RIO DB BAYAMON BASIN 50047850 RIO BAYAMON NR BAYAMON, PR LOCATION.--Lat 18°20'08", long 66°08'13", Hydrologic Unit 21010005, on left bank, at rock Quarry near Highway 174, 1.3 mi (2.1 km) south of colonia Santa Rosa and 4.7 mi (7.6 km) south of Bayam6n. DRAINAGE AREA.--41.8 mi> (108.3 km»). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--September 1964 to October 1970, June 1988 to current year. GAGE.—Water-stage recorder and crest-stage gage. Elevation of gage is 98 ft (30 m), from topografic map. REMARKS.--Records fair except those for estimated daily discharges, which are poor. Diversion to the Ouaynabo water treatment plant, for municipal supply, made upstream from station (at Represa de San Juan). Flow is regulated by storage and release of water at Lago de Cidra (capacity 5,220 acre-ft), 10.5 mi (16.9 km) upstream. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES OCT NOV DEC JAN FEB APR MAY JUN JUL AUG SEP 1 15 47 2 12 35 3 9.8 19 4 7.6 20 5 9.2 17 6 7.3 17 7 29 29 8 59 121 9 7.5 67 10 6.0 17 11 5.8 12 12 5.7 10 13 5.6 10 14 5.8 9.5 15 6.5 9.0 16 5.7 13 17 5.6 11 18 8.3 9.4 19 7.1 8.8 20 6.7 8.5 21 7.0 23 22 6.4 56 23 6.3 34 24 6.2 103 25 6.2 19 26 6.2 16 27 11 15 28 7.7 18 29 6.4 14 30 51 13 31 39 --- TOTAL 378.6 801.2 MEAN 12.2 26.7 MAX 59 121 MIN 5.6 8.5 AC-FT 751 1590 CFSM .29 .64 IN. .34 .71 e Estimated 10 10 16 23 14 11 10 10 10 9.8 8.8 11 9.4 13 elO 8.8 8.8 8.8 8.4 15 61 12 11 8.9 8.4 8.2 10 9.7 9.0 8.6 8.6 381.2 12.3 61 8.2 756 .29 .34 STATISTICS OF MONTHLY MEAN DATA MEAN 37.7 50.3 MAX 129 174 (WY) 1991 1970 MIN 4.30 7.91 (WY) 1969 1965 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 49.5 263 1966 5.19 1968 FOR 8.8 8.0 7.6 7.5 1270 811 69 23 17 25 17 15 15 14 14 32 38 14 el3 e!2 ell ell elO elO elO elO e9.8 e9.9 e9.2 e9.2 e8.8 2539.8 81.9 1270 7.5 5040 1.96 2.26 FOR WATER 40.2 159 1969 5.30 1968 e8.6 e8.4 e8.6 e8.8 e8.4 e8.4 e8.4 e8.4 e8.8 e8.8 e8.8 e8.2 e8.2 e8.4 eS.O eS.O eS.O eS.O e8.4 eS.O eS.O e9.4 e8.4 e9.0 e8.4 e8.8 e8.5 e8.5 e8.5 ___ --- 245.1 8.45 9.4 8.0 486 .20 .22 YEARS 1964 23.7 75.3 1989 4.75 1965 e8.5 e8.5 e8.5 e8.4 e8.4 e8.4 e8.4 e8.3 e8.3 e8.3 e8.2 8.2 8.0 7.8 7.8 7.8 8.4 9.2 8.6 8.0 8.0 8.0 8.0 8.0 7.8 7.8 8.8 75 19 9.1 8.3 333.8 10.8 75 7.8 662 .26 .30 - 1992 20.3 52.9 1990 3.58 1965 1991 CALENDAR YEAR 7003. 19. 750 5. 5. 13890 . 6. 28 10 7. 7 2 Jul 16 2 Sep 15 8 Oct 11 46 23 1 7.6 19 18 8.6 7.9 8.4 8.1 8.8 8.8 9.1 8.5 8.8 8.8 8.1 7.5 7.9 7.9 8.0 8.1 12 8.4 7.6 7.5 7.5 7.5 7.5 7.4 7.5 24 26 --- 300.8 10.0 26 7.4 597 .24 .27 123 87 19 12 10 13 11 9.0 8.8 9.2 8.2 8.1 8.1 7.9 7.4 57 22 25 29 25 38 39 66 181 33 122 51 30 23 20 18 1120.7 36.2 181 7.4 2220 .86 1.00 19 16 15 14 13 13 15 17 18 14 15 12 12 12 11 10 10 9.6 9.4 9.1 16 11 9.3 8.6 8.4 8.2 8.2 8.0 7.7 7.4 356.9 11.9 19 7.4 708 .28 .32 7.4 7.5 7.5 7.6 7.8 7.6 7.2 11 14 9.5 9.5 9.1 8.8 9.6 11 8.5 8.3 7.8 8.3 7.9 7.6 7.2 7.4 17 8.3 6.9 9.4 7.5 6.5 6.0 6.4 266.1 8.58 17 6.0 528 .21 .24 7.0 7.0 7.2 9.2 71 103 19 19 271 89 52 46 41 48 41 36 32 30 29 30 28 27 25 23 23 23 24 21 20 20 24 1245.4 40.2 271 7.0 2470 .96 1.11 19 18 18 21 26 37 25 17 15 15 13 11 30 16 11 12 15 12 78 105 58 15 18 9.9 8.9 8.5 8.3 7.5 7.1 7.2 --- 662.4 22.1 105 7.1 1310 .53 .59 , BY WATER YEAR (WY) 21.6 72.7 1971 5.36 1965 FOR 1992 8632 23 1270 5 5 6980 14 17120 7 36 9 7 48.1 131 1966 6.88 1967 WATER YEAR .0 .6 Jan 5 .6 Oct 13 .8 Oct 11 Jan 5 . 18 Jan 5 .56 .68 .5 .5 21.2 60.8 1970 4.26 1967 21.3 46.6 1970 5.98 1967 WATER 35 59 12 5500 2 2 28000 20 25480 11 61 13 4 46.1 137 1970 15.0 1991 YEARS 1964 .2 .7 .1 Oct .2 Apr .4 Apr Oct .20 Oct .84 .43 .8 44.2 146 1989 6.02 1967 - 1992 1966 1968 9 1970 19 1965 14 1965 9 1970 9 1970 RIO DB BAYAMON BASIN 50047990 RIO GDAYNABO NEAR BAYAMON, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°22'32", long 66°07'59", at bridge on Highway 833, 0.2 mi (0.3 km) upstream from Rio de Bayamon, and 2.3 mi (3.7 km) southeast of Bayamon plaza. DRAINAGE AREA.--73.2 mi 1 (189.6 km1 ). PERIOD OP RECORD.--Water year* 1958, 1964, 1971-73, 1976, 1979 to current year. HATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 787 OCT 17 DEC 31 FEB 25 APR 23 JUN 25 AUG 06 DATE 1991 1992 DIS- PH CHARGE, SPB- HATER INST. CIPIC WHOLE CUBIC CON- FIELD TEMPER- TUR- PBBT DUCT- (STAND- ATURB BID- TIME PER ANCB ARD WATER ITY SECOND (US/CM) UNITS) (DBG C) (NTU) 1400 25 461 7.7 28.0 13 HIS 28 420 7.5 22.5 19 1200 41 438 7.6 23.5 6.4 1250 20 S06 7.1 29.0 3.2 081S 30 470 7.3 28.0 3.2 1150 75 278 7.2 27.5 22 HARD- HARD- NESS OXYGEN, DIS- SOLVED (MG/L) 4.8 5.0 5.4 3.3 3.1 4.0 MAGNE- SODIUM POTAS- NESS NONCARB CALCIUM SIUM, SODIUM, AD- TOTAL WH WAT DIS- DIS- DIS- SORP- SIUM, DIS- (MG/L TOT FLD SOLVED SOLVED SOLVED TION SOLVED OCT 17 DEC 31 PBB 25 APR 23 JUN 25 AUG 06 DATE 1991 . . . 1992 . . . AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L CACO3 ) CACO3 170 4 __ -- 160 7 -_ 180 12 AS CA) AS MG) AS NA) 46 13 30 1 __ _- 44 13 30 1 __ 49 13 30 1 SOLIDS, RESIDUE PLUG- SILICA, SUM OP SOLIDS, TOTAL OCT 17 DEC 31 PBB 25 APR 23 JUN 25 AUG 06 K = RIDE, DIS- SOLVED DATE (MG/L AS P) 1991 0.10 ... 1992 ... 0.20 ... 0.20 non- ideal count DIS- CONSTI- DIS- AT 105 AS 3 - - 4 - 3 NITRO- GEN, SOLVED TUENTS, SOLVED DBG. C, NITRATE (MG/L DIS- (TONS SUS- AS SOLVED PER PBNDBD SI02) (MG/L) DAY) (MG/L) 33 274 18.8 5 35 10 27 280 15 17 3 30 290 23.5 18 TOTAL (MG/L AS N) 0.440 0.450 0.460 0.350 0.240 0.510 K) .7 - - .5 - .4 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 70 79 82 43 42 54 ALKA- OXYGEN COLI- STREP - DEMAND, FORM, TOCOCCI CHEM- FECAL, PBCAL, ICAL 0.7 KF AGAR (HIGH UM-MP (COLS. LEVEL) (COLS./ PER (MG/L) 100 ML) 100 ML) 22 3500 K200 13 2200 6100 16 5300 23000 37 3000 710 11 K1100 K200 15 4800 13000 LINITY WAT WH TOT PET FIELD MG/L AS CACO3 NITRO- GEN, NITRITE TOTAL (MG/L AS 0. 0. 0, 0, 0, 0. N) ,030 .040 ,030 .050 ,060 .100 160 150 150 170 150 180 CHLO- SULPATB RIDE, SULPIDB DIS- DIS- TOTAL SOLVED SOLVED (MG/L (MG/L (MG/L AS NITRO- GEN, N02+N03 TOTAL (MG/L AS 0. 0, 0, 0, 0, 0 N) .470 .490 .490 .400 .300 * .610 S) AS S04) AS CL) <O.S 12 __ __ <O.S 21 __ 17 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.110 0.090 0.100 1.80 2.40 0.230 40 -- -- 43 -- 39 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.89 0.31 0.30 0.70 0.70 0.37 182 RIO DE BAYAMON BASIN 50047990 RIO GUAYNABO NEAR BAYAMON, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTBMBBR 1992 DATE OCT 1991 17.. . DEC 31. . . FBB 1992 25.. . APR 23.. . JUN 25. . . AUG 06. . . DATE OCT 1991 17. .. DBC 31. . . FEB 1992 25. . . APR 23. . . JUN 25. . . AUG 06. .. NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 1.0 0.40 0.40 2.5 3.1 0.60 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) 700 -- -- 370 -- -- NITRO- GEN, TOTAL (MG/L AS N) 1.5 0.89 0. 89 2.9 3.4 1.2 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) 12 -- -- 2 -- -- NITRO- GEN, TOTAL (MG/L AS N03) 6.5 3.9 3.9 13 15 5.4 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MM) 230 -- -- 240 -- -- PHOS- PHORUS TOTAL (MG/L AS P) 0.290 0.310 0.270 0.750 1.30 0.310 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) 0.10 -- -- <0.10 -- -- BARIUM, TOTAL ARSENIC RBCOV- TOTAL BRABLB (UG/L (UG/L AS AS) AS BA) <1 <100 __ __ 2 200 __ <1 <100 SILVER, SELB- TOTAL NIUM, RBCOV- TOTAL BRABLB (UG/L (UG/L AS SE) AS AG) <1 <1 __ __ <1 <1 __ _- BORON, TOTAL RECOV- ERABLE (UG/L AS B) 30 -- -- 10 -- 50 ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) 60 -- -- <10 -- -- CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) 5 -- -- <1 -- <1 CYANIDE TOTAL (MG/L AS CN) <0.010 -- -- <0.010 -- -- CHRO- MIUM, COPPER, TOTAL TOTAL RECOV- RECOV- ERABLE BRABLB (UG/L (UG/L AS CR) AS CU) 3 30 __ __ 4 10 __ <1 <10 METHY- LBNB BLUB ACTIVE PHENOLS SUB- TOTAL STANCE (UG/L) (MG/L) 2 0.06 __ __ <1 0.07 __ -- RIO DB BAYAMON BASIN 783 50048510 RIO DB BAYAMON AT FLOOD CHANNEL AT BAYAMON, PR WATER-QUALITY RECORDS LOGATION.--Lat 18°24'29", long 66°09'04", at bridge on Highway 890, 1.0 (1.6 km) downstream from bridge on Highway 2, and 3.2 mi (5.1 km) above mouth. DRAINAGE AREA.--71.9 mi' (186.2 km1 ). PERIOD OF RECORD.--Water year* 1974 to current year. REMARKS.--Prior to 1979 •ampling site was 0.8 mile (1.3 km) downstream but was changed because of flood channel construction. WATER-QUALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 07. .. DEC 11. .. FEB 1992 25. .. APR 23. .. JUN 25. .. ADG 07. . . TIME 1215 1415 1330 0940 1050 1240 DIS- CHARGE, INST. COB 1C FEET PER SECOND 22 24 43 42 19 48 SPE- CIFIC CON- DUCT- ANCE (DS/CM) 432 442 407 485 451 377 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.8 7.8 7.2 7.2 7.6 7.0 TEMPER- ATURE WATER (DBG C) 30.0 27.0 26.0 26.0 28.0 28.7 TUR- BID- ITY (NTU) 10 3.8 1.6 20 1.2 46 OXYGEN, DIS- SOLVED (MG/L) 7.2 5.8 7.0 4.4 7.5 3.7 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 89 72 52 54 94 60 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 19 21 18 17 22 27 COLI- FORM, FECAL, 0.7 UM-MF (COLS./ 100 ML) 40000 K17000 K800 K20000 K1100 4100 STREP- TOCOCCI FECAL, KF AGAR (COLS. PER 100 ML) K1300 K100 23000 K1600 K200 2100 DATE OCT 1991 07. .. DEC 11. . . FBB 1992 25... APR 23. . . JUN 25. .. AUG 07. . . HARD- NESS TOTAL (MG/L AS HARD- NESS NONCARB WH WAT TOT FLD MG/L AS CALCIUM DIS- SOLVED (MG/L MAGNE- SIUM, DIS- SOLVED (MG/L SODIUM, DIS- SOLVED (MG/L SODIUM AD- SORP- TION RATIO CAC03) CAC03 140 150 140 AS CA) AS MG) AS NA) 44 13 26 39 13 37 11 24 19 ALKA- POTAS- LINITY CHLO- SIUM, WAT WH SULFATB RIDE, DIS- TOT PET SULFIDB DIS- DIS- SOLVED FIELD TOTAL SOLVED SOLVED (MG/L MG/L AS (MG/L (MG/L (MG/L AS K) 0.9 2.6 0.9 3.6 0.7 2.7 CACO3 160 160 140 170 180 160 AS S) AS S04) AS CL) <0.5 18 <0.5 19 19 31 34 27 DATE OCT 1991 07. .. DEC 11. .. PBB 1992 25. . . APR 23. .. JUN 25. . . AUG 07. .. FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.20 -- -- 0.20 -- 0.10 SILICA, DIS- SOLVED (MG/L AS SIO2) 28 -- -- 24 -- 23 SOLIDS, SUM OF CONSTI - TUENTS, DIS- SOLVED (MG/L) 259 -- -- 240 -- 224 SOLIDS, DIS- SOLVED (TONS PER DAY) 15.2 -- -- 27 -- 29 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 17 17 6 48 18 79 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.310 0.380 0.310 0.470 0.260 0.600 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.060 0.070 0.040 0.130 0.030 0.020 NITRO- GEN, NO2 * NO3 TOTAL (MG/L AS N) 0.370 0.450 0.350 0.600 0.290 0.620 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.380 0.750 0.450 1.20 0.060 0.090 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.32 0.45 0.55 0.70 0.34 0.41 K = non-ideal count 184 RIO DB BAYAMON BASIN 50048510 RIO DB BAYAMON AT FLOOD CHANNEL AT BAYAMON, PR—Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 07.. . DEC 11.. . FEB 1992 25... APR 23... JUN 25... ADG 07... DATS OCT 1991 07. .. DEC 11.. . FBB 1992 25... APR 23.. . JUN 25.. . ADG 07. .. NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0'.70 1.2 1.0 1.9 0.40 0.50 TOTAL RECOV- ERABLE (DG/L AS FB) 850 -- -- 2700 -- -- NITRO- GEN, TOTAL (MG/L AS N) 1.1 1.7 1.3 2.5 0.69 1.1 TOTAL RECOV- ERABLE (UG/L AS PB) 2 -- -- 3 -- -- NITRO- GEN, TOTAL (MG/L AS N03) 4.7 7.3 6.0 11 3.1 5.0 MANGA- TOTAL RECOV- ERABLE (DG/L AS MN) 280 -- -- 310 -- -- PHOS- PHORUS TOTAL (MG/L AS P) 0.210 0.270 0.260 0.480 0.110 0.160 TOTAL RECOV- ERABLE (DG/L AS HG) <0.10 -- -- <0.10 -- -- BARIUM, TOTAL ARSENIC RBCOV- TOTAL ERABLB (DG/L (DG/L AS AS) AS BA) <1 100 __ __ 2 200 __ __ SBLB- TOTAL NIUM, RBCOV- TOTAL BRABLB (DG/L (DG/L AS SB) AS AG) <1 <1 __ __ <1 <1 __ __ BORON, TOTAL RECOV- ERABLE (DG/L AS B) <10 -- -- 30 -- -- TOTAL RECOV- ERABLE (DG/L AS ZN) <10 -- -- 20 -- -- CADMIUM TOTAL RECOV- ERABLE (DG/L AS CD) <1 -- -- <1 -- -- CYANIDE TOTAL (MG/L AS CN) <0.010 -- -- <0.010 -- -- CHRO- MIUM, COPPER, TOTAL TOTAL RBCOV- RECOV- ERABLE BRABLB (DG/L (DG/L AS CR) AS CU) 2 <10 __ __ 20 10 __ -- -- MBTHY- BLUB ACTIVE PHENOLS SUB- TOTAL STANCE (DG/L) (MG/L) 1 0.06 __ __ 1 0.11 __ __ PESTICIDE ANALYSES WATER-QUALITY DATA DATE TIME JUN 1992 25... 1050 RIO PUERTO NUBVO BASIN 185 50048770 RIO PIBORAS AT EL SBNORIAL, PR LOCATION.--Lat 18°21'51", long 66 0 03'56", Hydrologic Unit 21010005, on right bank, in the Ribera* of Sefiorial Housing area, 0.6 mi (1.0 km) west of Highway 176 and 2.7 mi (4.3 km) southwest of Rio Piedras Plaza. DRAINAGE AREA.--7.49 mi 1 (19.40 km 1 ). HATER-DISCHARGE RECORDS PERIOD OF RECORDS.--March 1988 to current year. GAGE.--Hater-stage recorder. Elevation of gage is 98.4 ft (30.0 m), from topographic nap. REMARKS.--Records poor. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR MAY JUN JUL AUG 1 11 9.7 2 6.3 31 3 5.7 17 4 5.9 12 5 8.6 6.4 6 4.4 7.7 7 4.1 25 8 12 47 9 4.7 15 10 3.7 10 11 3.6 5.7 12 3.4 e5.9 13 3.1 e7.7 14 3.4 e4.1 15 4.5 7.9 16 3.2 12 17 3.1 e8.0 18 76 e6.0 19 16 eS.O 20 6.4 4.0 21 5.9 71 22 7.6 58 23 5.9 30 24 5.5 e38 25 4.2 11 26 6.4 11 27 4.5 9.5 28 3.7 8.6 29 3.4 8.8 30 19 7.3 31 7.7 --- TOTAL 262.9 500.3 MEAN 8.48 16.7 MAX 76 71 MIN 3.1 4.0 AC-FT 521 992 CFSM 1.13 2.23 IN. 1.31 2.48 e Estimated STATISTICS OP MONTHLY MEAN MEAN 31.1 16.5 MAX 57.3 24.2 (WY) 1991 1989 MIN 8.48 7.51 (WY) 1992 1991 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN- DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 6.9 10 20 14 12 6.3 4.7 6.7 5.9 4.7 4.9 11 5.9 7.1 4.1 6.7 6.7 9.1 7.8 22 12 15 13 12 5.9 6.2 6.6 3.7 5.2 9.7 3.6 269.4 8.69 22 3.6 534 1.16 1.34 DATA 12.4 16.8 1991 8.69 1992 FOR 10 e6.0 e4.5 12 245 163 16 5.6 19 73 13 8.7 13 5.0 5.4 e25 e!6 14 6.5 7.4 6.5 6.9 4.8 6.7 12 11 9.1 9.7 8.3 7.7 6.5 757.3 24.4 245 4.5 1500 3.26 3.76 FOR WATER 16.3 24.4 1992 12.1 1989 8.8 e!4 ell e7.6 e7.2 6.8 6.7 7.2 5.5 5.9 6.1 6.4 5.4 7.0 6.8 6.7 7.8 7.4 9.6 7.0 8.0 12 5.8 7.8 8.2 7.4 6.6 6.6 6.6 ___ --- 219.9 7.58 14 5.4 436 1.01 1.09 YEARS 1988 15.1 23.6 1991 7.58 1992 4.7 4.4 5.0 5.7 4.4 5.2 4.0 4.7 3.9 5.0 5.6 4.4 5.7 5.9 4.5 5.6 8.0 5.6 6.5 5.9 5.8 3.4 5.2 3.4 5.0 5.2 4.7 88 5.9 2.6 4.3 238.2 7.68 88 2.6 472 1.03 1.18 - 1992 12.4 19.5 1990 7.68 1992 1991 CALENDAR YEAR 4755. 13. 145 2. 2. 9430 1. 23. 25 7. 3. 1 0 Aug 21 5 Aug 11 7 Aug 8 74 62 0 5 4.2 4.3 4.5 4.7 3.1 3.0 4.6 4.9 4.9 12 5.8 4.4 2.0 3.2 1.6 2.0 4.1 4.6 49 7.8 3.0 2.5 4.0 5.4 6.8 6.5 5.5 3.8 100 51--- 323.2 10.8 100 1.6 641 1.44 1.61 139 148 20 13 11 63 7.9 5.8 15 8.3 6.8 3.9 3.2 2.8 2.4 98 11 68 26 13 7.2 5.1 116 140 45 211 66 32 71 83 20 1462.4 47.2 211 2.4 2900 6.30 7.26 41 31 12 8.5 6.5 10 e!30 e80 e25 e!5 elO eS.O elO 10 9.2 6.1 4.8 4.4 5.2 4.9 12 7.6 6.4 5.7 5.9 5.2 5.4 4.7 4.8 4.3 --- 493.6 16.5 130 4.3 979 2.20 2.45 4.2 4.0 3.9 11 6.9 6.1 4.6 13 26 9.4 22 9.0 28 14 13 6.6 6.9 5.7 5.3 47 e!8 e!2 e9.3 el!6 e!7 e8.4 e61 e!9 e9.8 e7.6 el!7 641.7 20.7 117 3.9 1270 2.76 3.19 e22 e28 e!7 e!2 e!61 e27 e21 e7.3 e277 e281 «31 e!6 e25 e289 «30 ell e4.7 e4.4 e4.1 e5.4 e621 e40 e28 e!2 ell e!3 e9.3 7.0 7.4 22 e28 2072.6 66.9 621 4.1 4110 8.93 10.29 ell e7.6 e5.4 3.8 7.6 44 9.1 5.4 4.7 4.7 5.4 5.4 6.5 7.4 11 8.4 10 7.4 42 52 12 7.7 41 12 11 12 11 11 12 24--- 412.5 13.7 52 3.8 818 1.84 2.05 , BY WATER YEAR (WY) 13.8 23.2 1988 10.4 1991 FOR 1992 7654 20 621 1 3 4250 14 15180 2 38 43 7 4 20.8 47.2 1992 9.09 1989 WATER YEAR .0 .9 Aug 21 .6 Apr 15 .1 Apr 12 Aug 21 .27 Aug 21 .79 .01 .5 .1 14.1 24.8 1989 8.74 1990 16.0 26.6 1989 7.43 1990 WATER 18 20 15 621 1 2 4680 16 13500 2 33 40 8 4 29.3 66.9 1992 6.60 1990 YEARS 1988 .6 .9 .7 Aug .6 Apr .7 Aug Aug . 0 8 Aug .49 .81 .4 .7 27.4 59.5 1989 6.90 1991 - 1992 1992 1990 21 1992 15 1992 8 1991 24 1988 24 1988 786 RIO PUERTO NUBVO BASIN 50048770 RIO PIBDRAS AT EL SBNORIAL, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORDS.-- Water year* 1988 to current year. INSTRUMENTATION.-- USD-77 and automatic sediment sampler. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: April 1988 to September 1992. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATION: Maximum daily mean, 24,600 mfl/L Sep. 18, 1989; Minimum daily mean, 2 mo/L November 18, 1988. SEDIMENT LOADS: Maximum daily mean, el!4,000tons (e!03,OOOtonnes) Sep. 18, 1989; minimum daily mean, 0.04 ton (0.03 tonne) May 6, 1990. EXTREMES FOR WATER YEAR 1992.-- SBDIMENT CONCENTRATION: Maximum daily mean, 10,700 mjj/L Jan. 05, 1992; minimum daily mean, 10 mg/1 several days. SEDIMENT LOADS: Maximum daily mean, el!4,000 tons (e!03,000 tonnes) Jan. 05, 1992; minimum daily mean, 0.05 ton (0.04 tonne) Apr. 15. SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN DISCHARGE (CFS) 11 6.3 5.7 5.9 8.6 4.4 4.1 12 4.7 3.7 3.6 3.4 3.1 3.4 4.5 3.2 3.1 76 16 6.4 5.9 7.6 5.9 5.5 4.2 6.4 4.5 3.7 3.4 19 7.7 262.9 MEAN CONCEN- TRATION (MG/L) OCTOBER 126 71 49 61 83 33 29 158 37 29 25 24 22 25 39 24 24 1670 148 53 51 61 53 31 36 71 38 22 37 242 77 _._ SEDIMENT DISCHARGE (TONS/DAY) 8.0 1.4 .79 1.1 3.0 .37 .31 34 .50 .29 .22 .21 .18 .26 .68 .21 .21 2990 7.3 .89 .84 1.5 1.1 .44 .39 2.8 .49 .23 .47 45 2.7 3105.88 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) NOVEMBER 9 31 17 12 6 7 25 47 15 10 5 eS e7 e4 7 12 e8 e6 e5 4 71 58 30 e38 11 11 9 8 8 7 .7 .4 .7 .7 .9 .7 .1 .9 .0 .0 .0 .0 .5 .6 .8 .3 102 456 220 123 60 77 659 700 188 110 48 54 76 39 71 126 39 50 40 38 1400 812 441 459 94 106 79 67 96 89 4.3 87 29 5.7 1.3 2.2 99 158 9.4 4.1 .80 e.84 e2.0 e.45 2.4 10 e.84 e.82 e.54 .67 1660 289 157 e83 2.8 3.6 2.3 1.5 2.7 1.7 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) DECEMBER 6.9 10 20 14 12 6.3 4.7 6.7 5.9 4.7 4.9 11 5.9 7.1 4.1 6.7 6.7 9.1 7.8 22 12 15 13 12 5.9 6.2 6.6 3.7 5.2 9.7 3.6 64 98 255 152 165 58 40 35 33 25 39 151 63 95 32 87 61 52 99 299 180 220 190 125 56 44 67 30 42 99 22 1.3 3.2 25 6.1 7.2 1.1 .54 .63 .55 .29 .55 22 1.8 3.4 .38 2.4 1.2 1.5 3.7 51 7.1 13 10 6.9 1.1 .95 2.5 .31 .78 15 .23 500.3 2622.96 269.4 191.71 e Estimated RIO PUERTO NUEVO BASIN 50048770 RIO PIBORAS AT EL SENORIAL, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 187 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) JANUARY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL 10 e6. e4. 12 245 163 16 5. 19 73 13 8. 13 5. 5. e25 e!6 14 6. 7. 6. 6. 4. 6. 12 11 9. 9. 8. 7. 6. 757. 0 5 6 7 0 4 5 4 5 9 8 7 1 7 3 7 5 3 127 67 42 126 5850 3180 175 53 245 1230 136 68 165 22 24 21 126 138 55 50 50 64 31 40 129 110 83 90 53 34 17 ___ 14 el e 5 11100 3010 9 62 428 5 1 11 1 6 6 1 1 1 5 5 2 2 1 14688 .1 .51 .9 .8 .88 .5 .4 .30 .34 .4 .5 .1 .0 .1 .83 .6 .37 .74 .5 .1 .4 .7 .2 .76 .33 .36 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) FEBRUARY 8 e!4 ell e7 e7 6 6 7 5 5 6 6 5 7 6 6 7 7 9 7 8 12 5 7 8 7 6 6 6 - - 219 .8 .6 .2 .8 .7 .2 .5 .9 .1 .4 .4 .0 .8 .7 .8 .4 .6 .0 .0 .8 .8 .2 .4 .6 .6 .6 -- -- .9 38 174 131 53 40 42 48 46 41 35 30 30 30 65 68 58 71 79 91 64 70 138 44 58 70 68 60 56 56 ___ --- ___ e20 e4 el e 1 1 1 1 1 2 1 1 16 1 1 1 1 1 1 70 .86 .5 .1 .74 .76 .92 .96 .63 .59 .47 .50 .45 .7 .7 .2 .8 .9 .7 .3 .5 .69 .2 .5 .4 .1 .0 .0 ___ --- .17 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MARCH 4. 4. 5. 5. 4. 5. 4. 4. 3. 5. 5. 4. 5. 5. 4. 5. 8. 5. 6. 5. 5. 3. 5. 3. 5. 5. 4. 88 5. 2. 4. 238. 7 4 0 7 4 2 0 7 9 0 6 4 7 9 5 6 0 6 5 9 8 4 2 4 0 2 7 9 6 3 2 30 16 15 30 40 41 36 34 33 35 43 40 41 61 82 103 119 84 55 59 51 24 47 23 56 41 39 1900 98 73 70 ___ .37 .19 .20 .46 .48 .57 .39 .42 .34 .47 .65 .47 .62 .97 .99 1.6 2.6 1.3 1.2 1.1 1.1 .21 .78 .20 .90 .78 .72 4820 1.6 .51 .82 4843.01 e Estimated 188 RIO PUERTO NOBVO BASIN 50048770 RIO PIEDRAS AT EL SENORIAL, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CFS) 4.2 4.3 4.5 4.7 3.1 3.0 4.6 4.9 4.9 12 5.8 4.4 2.0 3.2 1.6 2.0 4.1 4.6 49 7.8 3.0 2.5 4.0 5.4 6.8 6.5 5.5 3.8 100 51___ MEAN CONCEN- TRATION (MG/L) APRIL 60 47 35 37 22 22 35 61 49 137 45 22 18 13 10 10 50 44 2110 97 45 19 35 64 80 77 80 49 3220 803 ___ SEDIMENT DISCHARGE (TONS/DAY) .68 .54 .42 .46 .18 .18 .44 .81 .87 16 .73 .28 .09 .12 .05 .06 .87 .77 1970 2.1 .37 .12 .60 1.1 2.2 2.1 1.6 .70 3710 372 ___ MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MAY MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) JUNE 139 148 20 13 11 63 7.9 5.8 15 8.3 6.8 3.9 3.2 2.8 2.4 2160 2460 186 135 US 1090 69 64 202 77 57 44 32 30 12 3400 2030 11 6 4 969 1 1 39 2 3 .4 .6 .8 .2 .3 .2 .50 .32 .27 .08 98 11 68 26 13 7.2 5.1 116 140 45 211 66 32 71 83 20 2090 117 1410 312 145 51 42 2480 2100 564 4330 979 417 1350 1420 262 2280 S. 1530 34 14 2080 1460 92 7860 245 90 1280 623 16 ,6 ,93 ,63 41 31 12 8.5 6.5 10 e!30 e80 e25 e!5 elO e8.0 elO 10 9.2 6.1 4.8 4.4 5.2 4.9 12 7.6 6.4 5.7 S.9 5.2 5.4 4.7 4.8 4.3 699 366 86 82 60 96 2070 1600 711 216 120 80 80 125 97 61 32 26 49 34 131 69 63 29 23 21 18 16 16 12 385 38 2.8 2.2 1.2 7.7 e727 e346 e48 e8.7 e3.2 el. 7 e2.2 5.3 6.1 1.3 .42 .28 .78 .46 7.3 1.7 1.6 .48 .38 .33 .28 .22 .22 .15 TOTAL 323.2 6086.44 1462.4 24080.83 493.6 1601.00 e Estimated DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CFS) 4.2 4.0 3.9 11 6.9 6.1 4.6 13 26 9.4 22 9.0 28 14 13 6.6 6.9 5.7 5.3 47 e!8 e!2 e9.3 el!6 e!7 e8.4 e61 e!9 e9.8 e7.6 el!7 TOTAL 641.7 YBAR e 7654.0 Estimated RIO PUERTO NOBVO BASIN 50048770 RIO PIBDRAS AT EL SBNORIAL, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) 789 JULY 15 20 20 117 53 27 25 121 368 86 289 50 440 320 201 81 75 52 50 805 174 140 102 2270 229 125 1020 208 104 77 2290 .18 .21 .22 25 1.1 .43 .34 5.5 55 2.6 34 1.3 171 15 12 1.7 2.4 .93 .87 519 e8.5 e4.5 e2.6 e2800 elO e2.8 e777 ell e2.8 el.6 e3160 7629.58 261583.51 MEAN DISCHARGE (CPS) MEAN CONCEN- TRATION (MG/L) SEDIMENT DISCHARGE (TONS /DAY) MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AUGUST e22 e28 e!7 e!2 e!61 e27 e21 e7.3 e277 e281 e31 e!6 e25 e289 e30 ell e4.7 e4.4 e4.1 e5.4 e621 e40 e28 e!2 ell e!3 e9.3 7.0 7.4 22 e28 465 411 336 225 3000 375 311 76 5190 5240 437 264 330 5740 360 167 114 94 60 42 10700 767 466 114 108 114 105 75 84 306 420 e28 e203 e!5 e7 e5200 e27 e98 el e23100 e24700 e37 ell e69 e25700 e41 e5 el el e e el!4000 e83 el!3 e3 e3 e* e2 1 1 91 e60 .3 .5 .0 .5 .1 .66 .61 .7 .2 .0 .6 .8 .9 ell e7. e5. 3. 7. 44 9. 5. 4. 4. 5. 5. 6. 7. 11 8. 10 7. 42 52 12 7. 41 12 11 12 11 11 12 24 -- SEPTEMBER 6 4 g 6 i 4 7 7 4 4 5 4 4 4 7 - 114 84 60 40 47 764 86 63 41 37 41 44 SO 60 45 22 54 77 720 884 143 82 792 132 110 91 102 108 97 296 ___ •3. •1. e. . • 763 2. . . . . , 1. 1. 1. 1. 733 627 6. 2. 814 5. 3. 2. 3. 3. 3. 67 - 4 7 87 41 96 1 91 51 46 59 64 87 2 3 48 5 5 1 0 0 6 8 0 4 4 -- 2072.6 193610.87 412.5 3052.70 790 RIO PUERTO NUBVO BASIN 50048770 RIO PIEDRAS AT EL SBNORIAL, PR--Continued WATER QUALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT DATS MAR 1992 28... APR 29. .. MAY 16... 23... ADO 05... TIME 1625 2255 1200 1753 0330 DIS- CHARGE, INST. CUBIC FEET PER SECOND e88 390 798 172 1390 SEDI- MENT, SUS- PENDED (MO/L) 43300 28700 45700 8200 38100 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) e!0300 30200 98500 3810 143000 SED. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM 24 27 22 26 25 BED. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM 34 37 33 34 35 SED. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 48 51 44 41 43 DATE MAR 1992 28. .. APR 29. . . MAY 16. .. 23. .. AUO 05. .. SBD. SUSP. FALL DIAM. PERCENT FINER THAN .016 MM 61 64 62 51 56 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM 76 75 68 56 67 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 89 90 83 75 83 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 96 97 92 85 92 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 98 99 98 95 98 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 99.7 99.8 99.7 99.5 99.8 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 100 100 100 100 100 RIO PUERTO NUBVO BASIN 50048770 RIO PIBDRAS AT EL SENORIAL, PR--Continued WATER QUALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT 797 DATE NOV 1991 20... MAR 1992 29... 30... MAY 01. .. 16. .. 23... TIME 1458 1830 1124 1850 1200 1908 STREAM- FLOW, INSTAN- TANEOUS (CFS) 5 479 16 209 798 381 SEDI- MENT, SUS- PENDED (MG/L) 444 4180 247 6310 1870 6730 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 6 5410 11 3560 4020 6920 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 98 82 94 85 77 54 RIO PUERTO HUEVO BASIN 50048800 RIO PIBDRAS NEAR RIO PIEORAS, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°22'i5-, long 660 03'40-, at bridge on Winiton Churchill Avenue in the El Sefiorial Housing area, 0.5 ai (0.8 km) west of Highway 176, and 2.5 mi (4.0 ka) southwest of Rio Piedras plaza. DRAINAGE AREA.--8.17 mi> (20.9 k»»). PERIOD OF RECORD.--Water years 1972 to current year. WATER QUALITY DATA, WATER YEAR OCTOBER 1991 TO SBPTBHBBR 1992 DATE OCT 1991 07. .. DEC 11. .. FBB 1992 10. .. MAY 04. .. JUN 08. . . AUO 20. .. TIME 1200 1050 1045 0830 1115 1200 DIS- CHARGE, INST. CUBIC FEET PER SECOND 4.1 5.6 5.7 7.0 28 9.3 SPE- CIFIC CON- DUCT- ANCE (US/CM) 442 433 380 430 415 437 PH WATER WHOLE FIELD (STAND- ARD UNITS) 8.1 7.4 7.5 7.3 7.2 7.9 TEMPER- ATURE WATER (DBG C) 28.5 23.5 25.0 24.0 27.0 29.4 TUR- BID- ITY (NTU) 8.5 2.4 3.7 14 7.0 5.0 OXYGEN, DIS- SOLVED (MG/L) 7.6 7.0 3.6 7.7 8.2 7.9 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 97 93 60 90 79 72 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 13 15 16 22 32 11 COLI- FORM, FECAL, 0.45 UM-MK (COLS./ 100 ML) 56000 K12000 K83000 39000 7000 3000 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 22000 6300 K40000 23000 21000 3500 DATE OCT 1991 07... DEC 11. .. FBB 1992 10. .. MAY 04. . . JUN 08. .. AUG 20... HARD- NESS CALCIUM TOTAL DIS- (MG/L SOLVED AS (MG/L MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L CAC03) AS CA) AS MG) AS NA) 160 43 13 29 140 38 12 28 150 43 13 27 SODIUM AD- SORP- TION RATIO 1 -- -- 1 -- 0.9 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 2.9 — — 3.4 — 3.2 ALKA- LINITY WAT WH TOT FBT FIELD MG/L AS CACO3 160 170 130 130 82 160 SULFIDB TOTAL (MG/L AS S) <0.5 — -- <0.5 — -- SULFATB DIS- SOLVED (MG/L AS SO4) 19 -- -- 33 -- 27 CHLO- RIDE, DIS- SOLVED (MG/L AS CL) 33 — — 40 — 35 SOLIDS, RESIDUE DATE OCT 1991 07.. . DEC 11... FBB 1992 10... MAY 04... JUN 08... AUG 20. . . FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.10 -- -- 0.20 -- 0.20 SILICA, DIS- SOLVED (MG/L AS SI02) 33 -- -- 25 -- 27 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 269 __ -- 258 -- 270 SOLIDS, DIS- SOLVED (TONS PER DAY) 2.95 -- -- 4.87 -- 6.78 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 22 1 1 20 133 13 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.640 0.790 0.630 0.570 0.600 0.650 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.150 0.180 0.040 0.030 0.100 0.060 NITRO- GEN, N02+N03 TOTAL (MG/L AS N) 0.790 0.970 0.670 0.600 0.700 0.710 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.930 0.740 0.310 0.350 1.40 0.250 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.37 0.56 0.39 0.25 0.90 0.15 non-ideal count RIO POBRTO NUBVO BASIN 50048800 RIO PIBDRAS NEAR RIO PIBDRAS, PR--Continued WATER QUALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 793 DATE OCT 1991 07.. . DEC 11.. . FBB 1992 10.. . MAY 04.. . JUN 08.. . AUG 20... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L NITRO- GEN, TOTAL (MG/L NITRO- GEN, TOTAL (MG/L PHOS- PHORUS TOTAL (MG/L ARSENIC TOTAL (UG/L BARIUM, TOTAL RECOV- ERABLE (UG/L BORON, TOTAL RECOV- ERABLE (UG/L CADMIUM TOTAL RECOV- ERABLE (UG/L CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L COPPER, TOTAL RECOV- ERABLE (UG/L AS N) 1.3 1.3 0.70 0.60 2.3 0.40 AS N) AS N03) AS P) 2.1 2.3 1.4 1.2 3.0 1.1 9.3 10 6.1 5.3 13 4.9 0.310 0.330 0.220 0.160 0.500 0.180 AS AS) AS BA) AS B) AS CD) AS CR) AS CO) 100 <10 <1 <10 200 40 <1 <1 <10 DATE OCT 1991 07.. . DEC 11. . . PBB 1992 10.. . MAY 04.. . JUN 08.. . AUG 20... IRON, TOTAL RECOV- ERABLE (UG/L AS PE) LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) SELE- NIUM, TOTAL (UG/L AS SB) SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CYANIDE TOTAL (MG/L AS CN) PHENOLS TOTAL (UG/L) 680 610 <1 210 120 <0.10 <0.10 <0.010 <0.010 MBTHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 0.06 0.05 DATE JUN 1992 08... TIME 1115 PCB, TOTAL (OG/L) PESTICIDE ANALYSES ALDRIN, TOTAL (OG/L) <0.010 CHLOR- DANB, TOTAL (OG/L) DDD, TOTAL (OG/L) DDE, TOTAL (OG/L) DOT, TOTAL (OG/L) <0.010 <0.010 <0.010 DI- AZINON, TOTAL (OG/L) DI- ENDO- BLDRIN SULPAN, TOTAL TOTAL (UG/L) (UG/L) 0.06 <0.010 <0.010 DATE JUN 1992 08. . . ENDRIN WATER UNFLTRD BTHION, REC (UG/L) TOTAL (UG/L) HEPTA- HEPTA- CHLOR CHLOR, BPOXIDB LINDANE TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) <0.010 <0.01 <0.010 <0.010 <0.010 MALA- THION, TOTAL (UG/L) 0.05 METH- OXY- CHLOR, TOTAL (UG/L) <0.01 METHYL PARA- THION, TOTAL (UG/L) <0.01 MIRBX, TOTAL (UG/L) <0.01 DATE JUN 1992 08. .. PARA- THION, TOTAL (UG/L) <0.01 NAPH- THA- LENES, POLY- CHLOR. TOTAL (UG/L) <0.10 PER- TOX- THANB APHENB, TOTAL TOTAL (UG/L) (UG/L) TOTAL TRI- THION (UG/L) <0.01 2,4-D, 2,4,5-T 2, 4-DP SILVBX, TOTAL TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) (UG/L) 0.04 <0.01 <0.01 <0.01 194 RIO PUERTO NDEVO BASIN 50049000 RIO PIBDRAS AT RIO PIKDRAS, PR LOCATION.--Lat 18°23'48', long 66°03'24', Hydrologic Onit 21010005, on left bank, at bridge on Highway 1, 0.3 mi (0.5 km) southwest of the plaxa in Rio Piedras, and 0.4 mi (0.6 km) downstream from diversion for water supply. DRAINAGE AREA.--12.5 mi 1 (32.4 km'). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--October 1958 (maximum discharge measurement only), 1959-64 (annual low-flow measurements only). July 1971 to September 1982, October 1987 to current year. GAGE.--Water-stage recorder and crest-stage gage. Elevation of gage is 50 ft (15 m), from topographic map. REMARKS.--Records fair. Low flow affected by diversions for water supply. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEE MAR APR MAY JON JUL AOG SEP 1 20 17 2 12 69 3 9.9 18 4 9.7 14 5 12 9.0 6 7.0 9.3 7 6.5 30 8 8.8 41 9 5.9 11 10 5.4 9.6 11 5.4 7.4 12 5.5 7.2 13 5.7 9.5 14 4.8 6.9 15 7.3 7.8 16 5.8 17 17 4.9 9.5 18 66 9.1 19 13 8.1 20 7.9 8.3 21 6.9 201 22 6.5 76 23 8.7 32 24 6.9 43 25 6.2 9.9 26 9.4 12 27 6.5 15 28 6.2 8.7 29 6.2 8.9 30 26 9.9 31 12 TOTAL 325.0 735.1 MEAN 10.5 24.5 MAX 66 201 MXN 4.8 6.9 AC-FT 645 1460 CFSM .84 1.96 IN. .97 2.19 12 13 37 14 14 12 8.9 15 14 8.8 9.1 16 8.9 14 7.6 20 7.3 7.8 7.1 29 13 13 13 9.1 8.6 9.6 13 9.6 9.7 23 11 408.1 13.2 37 7.1 809 l.OS 1.21 STATISTICS OF MONTHLY MEAN DATA MEAN 50.0 35.5 MAX 122 133 (WY) 1977 1978 MIN 10.5 8.16 (WY) 1992 1974 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS SO PERCENT EXCEEDS 90 PERCENT EXCEEDS 35.1 133 1976 9.88 1977 FOR 9.7 7.7 7.5 6.3 455 168 14 9.6 26 119 13 13 17 11 10 45 13 11 8.4 9.9 8.3 7.8 7.6 8.2 13 10 9.2 12 8.8 8.6 8.7 1076.3 34.7 455 6.3 2130 2.78 3.20 FOR WATER 17.4 34.7 1992 4.03 1973 8.8 13 12 9.2 8.6 8.1 8.6 8.9 8.6 8.6 8.7 8.8 8.9 8.9 8.8 7.8 8.7 7.5 9.2 6.5 6.3 20 7.3 7.5 7.2 7.4 7.8 7.0 7.0 ___ --- 255.7 8.82 20 6.3 507 .71 .76 YEARS 1971 20.2 98.9 1979 4.40 1977 5.8 6.6 6.2 11 7.3 7.4 7.9 7.4 6.8 7.9 8.5 7.6 9.0 12 8.3 8.7 15 11 10 9.1 9.8 7.2 10 7.8 7.9 8.5 8.2 132 13 8.0 9.1 395.0 12.7 132 5.8 783 1.02 1.18 - 1992 16.1 42.5 1972 2.67 1976 1991 CALENDAR YEAR 7849. 21. 403 4. 5. 15570 1. 23. 33 11 6. 3 5 Feb 18 8 Oct 14 6 Oct 11 72 36 9 9.5 8.9 9.2 10 9.6 10 12 19 15 21 13 11 6.8 6.9 6.0 6.7 7.2 13 73 13 9.4 5.7 6.6 7.5 8.4 8.7 8.8 9.7 561 121--- 1027.6 34.3 561 5.7 2040 2.74 3.06 202 149 11 6.9 5.7 76 12 8.8 14 17 14 8.6 7.9 7.8 8.3 122 19 87 59 24 46 IS 167 127 31 354 54 31 58 74 29 1846.0 59.5 354 5.7 3660 4.76 5.49 95 23 15 14 13 23 189 114 30 19 12 15 11 18 12 9.2 7.8 6.9 7.6 8.1 14 9.9 9.7 8.8 8.2 7.9 7.8 7.2 6.9 7.3 --- 730.3 24.3 189 6.9 1450 1.95 2.17 7.7 7.6 8.3 14 9.0 8.9 8.1 41 56 13 28 12 33 43 29 17 51 13 11 96 21 18 11 76 18 13 123 25 12 9.3 124 956.9 30.9 124 7.6 1900 2.47 2.85 33 40 18 20 155 16 20 8.3 222 154 20 IS 20 274 34 19 12 9.7 8.5 10 324 30 38 10 8.5 8.3 7.1 6.3 6.5 20 28 1595.2 51.5 324 6.3 3160 4.12 4.75 9.6 6.6 6.3 6.3 8.2 59 7.8 5.7 5. 5 5.4 8.1 5.6 6.5 6.2 6.3 5.8 17 6.6 18 62 16 6.7 99 8.7 6.3 5.8 5.0 4.8 5.4 85___ 505.2 16.8 99 4.8 1000 1.35 1.50 , BY WATER YEAR (WY) 23.8 64.0 1978 4.49 1974 FOR 1992 9856 26 561 4 5 4820 11 19550 2 29 59 9 6 32.6 121 1979 3.46 1975 WATER YEAR .4 .9 Apr 29 .8 Oct 14 .6 Oct 11 Apr 29 .65 Apr 29 .15 .33 .7 .5 18.9 59.7 1989 3.25 1974 20.6 55.6 1989 3.35 1976 WATER 29 54 11 2030 10000 21 21110 2 31 52 12 3 38.2 120 1979 4.30 1976 YEARS 1971 .1 .2 .9 Feb .26 May . 83 Aug Dec .02 Dec .33 .67 .3 38.0 112 1989 10.1 1973 - 1992 1979 1974 15 1979 19 1977 14 1976 11 1975 11 1975 RIO PUERTO NUBVO BASIN 50049000 RIO PIBDRAS AT RIO PIBDRAS, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORDS.-- Water years 1988 to current year. INSTRUMENTATION.-- USD-77 and automatic sediment sampler. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: October 1988 to September 1992. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATION: Maximum daily mean, 13,000 mg/L Sep. 18, 1989; Minimum daily mean, 4 mg/L June 4, 1990. SEDIMENT LOADS: Maximum daily mean, 165,000 tons (150,200 tonnes) Sep. 18, 1989; Minimum daily mean, 0.09 ton (0.08 tonne) Sep. 24, 1991. EXTREMES FOR WATER YEARS 1992.-- SBDIMENT CONCENTRATIONi Maximum daily mean, 2,080 mg/L Jan. 05, 1992; Minimum daily mean, 10 mg/L several days. SEDIMENT LOADS: Maximum daily mean, 8,860 tons (8,040 tonnes) Aug. 21, 1992; Minimum daily mean, 0.13 tons (0.12 tonnes) Sep. 28, 1992. 195 SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCEN- DISCHARGB TRATION SEDIMENT DISCHARGE DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 (CPS) (MG/L) (TONS/DAY) OCTOBER 20 12 9. 9. 12 7. 6. 8. 5. 5. 5. 5. 5. 4. 7. 5. 4. 66 13 7. 6. 6. 8. 6. 6. 9. 6. 6. 6. 26 12 9 7 0 5 8 9 4 4 5 7 8 3 8 9 9 9 5 7 9 2 4 5 2 2 87 39 38 22 39 14 14 22 14 13 11 12 10 11 24 11 10 459 48 18 15 16 19 14 12 28 13 13 13 127 44 13 1.6 1.1 .64 2.1 .25 .25 .98 .22 .21 .16 .17 .15 .14 1.0 .16 .13 784 3.5 .37 .28 .33 .43 .28 .19 1.6 .20 .20 .20 30 1.4 MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) (CFS) (MG/L) (TONS/DAY) NOVEMBER 17 69 18 14 9 9 30 41 11 9 7 7 9 6 7 17 9 9 8 8 201 76 32 43 9 12 15 8 8 9 - .0 .3 .6 .4 .2 .5 .9 .8 .5 .1 .1 .3 .9 .7 .9 .9 -- 53 438 64 53 25 19 166 205 23 15 14 15 25 17 16 58 17 16 17 19 821 535 147 232 26 34 58 21 20 20 ___ 2 306 6 2 66 48 6 2280 425 38 78 1 6 .4 .1 .7 .66 .49 .71 .38 .29 .28 .72 .31 .32 .0 .47 .40 .35 .42 .75 .9 .0 .50 .44 .50 ___ 12 13 37 14 14 12 8. 15 14 8. 9. 16 8. 14 7. 20 7. 7. 7. 29 13 13 13 9. 8. 9. 13 9. 9. 23 11 DECEMBER 9 8 1 9 6 3 8 1 1 6 6 6 7 35 24 187 33 22 23 22 42 38 24 19 59 24 46 17 93 17 15 15 143 47 51 39 16 16 17 40 21 22 95 34 1. . 43 1. . 2. 1. • . 7. . 3. 28 . 32 2. 2. 1. • 2. . . 21 1. 6 90 5 73 75 52 2 9 64 43 4 73 1 34 35 29 26 0 3 7 41 40 46 4 51 58 9 TOTAL 325.0 845.24 735.1 3274.09 408.1 160.30 196 RIO PUERTO NUEVO BASIN 50049000 RIO PIBDRAS AT RIO PIBDRAS, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) MEAN DISCHARGE DAY (CPS) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 9. 7. 7. 6. 455 168 14 9. 26 119 13 13 17 11 10 45 13 11 8. 9. 8. 7. 7. 8. 13 10 9. 12 8. 8. 8. 7 7 5 3 6 4 9 3 8 6 2 2 8 6 7 MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) JANUARY 81 18 27 11 2080 1260 41 25 138 862 41 43 64 24 23 241 53 44 41 40 40 38 29 21 35 19 19 19 17 16 16 3.5 .38 .58 .20 7290 1460 1.6 .65 37 679 1.6 2.0 4.7 .63 .56 178 2.2 1.3 .90 .97 .83 .73 .55 .42 1.4 .51 .46 .65 .36 .38 .40 8.8 13 12 9.2 8.6 8.1 8.6 8.9 8.6 8.6 8.7 8.8 8.9 8.9 8.8 7.8 8.7 7.5 9.2 6.5 6.3 20 7.3 7.5 7.2 7.4 7.8 7.0 7.0 FEBRUARY 16 35 38 17 16 16 16 16 16 16 16 16 16 16 15 15 13 13 16 15 13 88 13 13 13 13 13 15 23 .42 4.2 2.7 .47 .40 .34 .38 .40 .37 .34 .37 .38 .37 .37 .39 .33 .32 .28 .39 .28 14 .20 .27 .27 .27 .28 .28 .28 .44 MEAN DISCHARGE (CFS) 5.8 6.6 6.2 11 7.3 7.4 7.9 7.4 6.8 7.9 8.5 7.6 9.0 12 8.3 8.7 15 11 10 9.1 9.8 7.2 10 7.8 7.9 8.5 8.2 132 13 8.0 9.1 MEAN CONCEN- TRATION (MG/L) MARCH 35 40 33 38 14 11 13 13 13 13 14 14 15 21 27 36 37 26 20 16 17 17 29 14 15 15 15 982 47 34 27 SEDIMENT DISCHARGE (TONS/DAY) .54 .66 .55 3.0 .27 .25 .29 .25 .22 .28 .33 .26 .37 .69 .63 .89 1.6 .78 .46 .40 .44 .33 .96 .28 .34 .36 .36 2540 2.2 .75 .75 1076.3 9672.46 255.7 29.79 395.0 2559.49 RIO PUERTO NUEVO BASIN 197 50049000 RIO PIBDRAS AT RIO PIEDRAS, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CPS) 9. 8. 9. 10 9. 10 12 19 15 21 13 11 6. 6. 6. 6. 7. 13 73 13 9. 5. 6. 7. 8. 8. 8. 9. 561 121 -- 5 9 2 6 8 9 0 7 2 4 7 6 5 4 7 8 7 - MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) APRIL 20 20 20 20 18 17 19 67 51 86 41 35 14 11 11 12 13 47 512 45 29 10 10 10 10 10 10 13 2210 854 --- .53 .48 .53 .55 .45 .41 .63 9.0 4.1 11 2.0 1.5 .24 .21 .16 .22 .27 4.5 721 3.7 1.7 .14 .18 .21 .23 .24 .26 .34 15100 1190 --- MEAN DISCHARGE (CPS) 202 149 11 6.9 5.7 76 12 8.8 14 17 14 8.6 7.9 7.8 8.3 122 19 87 59 24 46 15 167 127 31 354 54 31 58 74 29 MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) MAY 1030 1000 33 11 10 604 35 23 49 57 38 19 16 15 15 789 64 553 373 86 314 48 1290 922 148 2050 287 141 365 457 127 2500 1370 1 1020 1 8 4 1 1570 3 850 223 7 267 2 1800 980 18 6250 62 18 254 170 17 .2 .21 .15 .2 .59 .4 .7 .8 .43 .32 .30 .34 .7 .9 .1 MEAN DISCHARGE (CPS) 95 23 15 14 13 23 189 114 30 19 12 15 11 18 12 9. 7. 6. 7. 8. 14 9. 9. 8. 8. 7. 7. 7. 6. 7. -- 2 8 9 6 1 9 7 8 2 9 8 2 9 3 - MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) JUNE 591 92 34 32 31 97 1200 815 120 69 31 46 28 72 40 20 15 13 16 19 39 19 19 17 14 13 16 19 19 19 ___ 1140 7.6 1.2 1.2 .95 18 2680 652 12 5.1 .97 2.9 .81 11 1.9 .45 .27 .22 .32 .42 1.9 .49 .48 .40 .31 .29 .32 .37 .34 .38 ___ TOTAL 1027.6 17054.78 1846.0 17402.34 730.3 4542.59 198 RIO PUERTO NUBVO BASIN 50049000 RIO PIEDRAS AT RIO PIBDRAS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CPS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL YEAR 7.7 7.6 8.3 14 9.0 8.9 8.1 41 56 13 28 12 33 43 29 17 51 13 11 105 21 18 11 76 18 13 123 25 12 9.3 124 965.9 9865.4 JULY 19 19 14 49 18 16 16 207 324 37 111 33 248 389 137 61 265 35 26 581 71 66 30 528 63 57 614 135 28 21 810 ... MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) AUGUST .38 .37 .31 6.4 .45 .39 .32 45 119 1.2 13 1.1 78 137 31 5.0 62 1.2 .72 690 4.4 4.3 .99 310 4.3 3.1 1240 13 1.0 .51 1520 4294.44 85825.74 33 40 18 20 155 16 20 8.3 222 154 20 15 20 274 34 19 12 9.7 8.5 10 324 30 38 10 8.5 8.3 7.1 6.3 6.5 20 28 1595.2 137 223 60 78 1260 127 119 21 1460 937 85 46 104 1050 153 64 31 26 21 16 1580 120 219 30 19 17 23 20 11 102 127 ... 26 86 3.6 8.2 2910 6.4 19 .54 4610 2090 5.8 2.4 7.7 3790 20 4.9 .99 .70 .48 .40 8860 13 80 .94 .41 .35 .42 .30 .19 47 24 22619.72 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) SEPTEMBER 9.6 6.6 6.3 6.3 8.2 59 7.8 5.7 5.5 5.4 8.1 5.6 6.5 6.2 6.3 5.8 17 6.6 18 62 16 6.7 99 8.7 6.3 5.8 5.0 4.8 5.4 85 65 28 17 13 18 399 19 12 11 12 26 11 11 11 11 10 64 18 104 957 65 15 393 21 11 10 10 10 10 244 2.7 .48 .28 .21 .50 584 .43 .17 .16 .17 .82 .17 .20 .17 .16 .16 6.6 .38 54 1410 10 .48 918 .52 .17 .15 .15 .13 .14 379 505.2 3370.50 RIO PUERTO NUEVO BASIN 50049000 RIO PIBDRAS AT RIO PIKDRAS, PR--Continued HATER QUALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 PARTICLE-SIZE DISTRIBUTION OP SUSPENDED SEDIMENT 199 DATE NOV 1991 02.. . JAN 1992 05.. . MAR 28. . . MAY 01.. . JUL 27.. . ADG 05.. . DATE NOV 1991 02.. . JAN 1992 05. .. MAR 28.. . MAY 01. . . JUL 27. .. AUG 05. . . TIME 0552 1637 1752 2037 1705 0330 SBD. SUSP. PALL DIAM. PERCENT FINER THAN .016 MM 61 64 64 69 62 60 DIS- CHARGE, INST. CUBIC FEET PER SECOND 548 2560 818 17600 1290 1390 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM 73 76 75 78 71 73 SEDI- MENT, SUS- PENDED (MG/L) 3800 10500 15800 8410 8430 17600 SBD. SUSP. SIEVE DIAM. PERCENT PINER THAN .062 MM 89 94 95 95 90 92 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 554 72500 34900 17600 29400 66000 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 96 98 99 99 96 98 SBD. SUSP. PALL DIAM. PERCENT FINER THAN .002 MM 38 48 34 45 40 27 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 99 99 99.6 99.7 98 99 SBD. SUSP. PALL DIAM. PERCENT PINER THAN .004 MM 47 50 40 52 47 45 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 99.7 99.7 99.8 100 99 99.8 SBD. SUSP. PALL DIAM. PERCENT FINER THAN .008 MM 53 56 47 60 54 52 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 100 100 100 100 99.8 100 200 RIO PUERTO NUBVO BASIN 50049000 RIO PIBDRAS AT RIO PIEDRAS, PR--Continued HATER QUALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT DATE OCT 1991 15... NOV 02. .. 21... 21. .. JAN 1992 05. .. 05. .. 16. . . MAR 28. . . MAY 01. .. 06. .. JUL 20. .. 27. . . AUG 05. .. 09. .. 14. .. SEP 20. . . 30. . . TIME 1544 0522 1900 2030 1517 1907 1905 1642 2207 0844 1610 1635 0300 1650 1445 0055 1410 STREAM- FLOW, INSTAN- TANEOUS (CFS) 32 336 344 409 476 1170 366 1690 1240 1110 438 1010 1790 1890 2760 581 956 SEDI- MENT, SUS- PENDED (MG/L) 338 3500 3020 1520 2470 4040 2670 5530 6880 5700 10200 6390 10100 11000 9380 14800 1720 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 29 3170 2810 1680 3170 12800 2640 25200 23000 17100 12100 17400 48700 56100 70000 23200 4440 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 99 94 95 97 89 89 78 70 92 83 67 79 87 74 89 96 59 RIO PUERTO NUBVO BASIN 20 1 50049100 RIO PIBDRAS AT HATO RKY, PR LOCATION.--Lat 18°24'34", long 66°04'10", Hydrologic Dnit 21010005, at bridge on Avenida Pifteiro at Bxpreso Las America8, and 0.8 mi (1.3 km) southwest of Hato Rey. DRAINAGE AREA.--15.4 mi> (39.9 km»). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--June 1970 to December 1987 (discharge measurements only), 1972 to December 1982 (maximum discharge only), January 1988 to current year. GAGE.--Water-stage recorder and crest-stage gage. Elevation of gage is 16 ft (5 m), from topographic map. REMARKS.--Records fair. Mean daily discharge affected by sewage discharges (approximately 2.0 ft'/s (0.06 m'/«)), 20 ft (6 m) upstream from gaging station. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN MAY JUN JUL ADO SEP 1 35 23 2 19 135 3 15 43 4 16 34 5 21 22 6 13 25 7 11 62 8 19 104 9 12 22 10 10 16 11 10 15 12 10 13 13 12 16 14 12 10 15 17 8.6 16 13 19 17 12 9.9 18 85 12 19 20 13 20 11 17 21 9.9 317 22 9.5 221 23 12 104 24 12 122 25 12 17 26 13 22 27 9.0 26 28 8.7 11 29 8.7 10 30 34 10 31 14 —— TOTAL 515.8 1479.5 MEAN 16.6 49.3 MAX 85 317 MIN 8.7 8.6 AC-FT 1020 2930 CFSM 1.09 3.24 IN. 1.26 3.62 STATISTICS OF MONTHLY MEAN MEAN 68.9 44.2 MAX 134 58.1 (WY) 1991 1990 MIN 16.6 23.9 (WY) 1992 1991 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 16 16 76 17 17 14 9.8 32 29 13 12 20 13 19 9.0 31 9.1 9.4 9.0 40 18 18 20 12 10 11 18 14 14 23 15 584.3 18.8 76 9.0 1160 1.24 1.43 DATA 34.3 55.6 1991 18.8 1992 FOR 13 11 13 11 637 320 43 26 63 315 30 40 39 19 17 72 25 19 16 16 16 14 14 13 25 19 14 17 12 11 11 1911 61.6 637 11 3790 4.06 4.68 FOR WATER 40.0 61.6 1992 29.9 1989 11 14 19 12 10 9.6 9.4 8.8 8.2 8.7 9.2 9.9 10 11 11 9.9 11 8.3 9.8 7.4 8.3 42 7.6 8.1 8.5 8.1 8.0 7.7 7.7 ___ --- 314.2 10.8 42 7.4 623 .71 .77 YEARS 1988 40.6 80.2 1991 10.8 1992 6.9 8.4 8.1 86 20 17 21 10 9.6 9.9 10 8.8 9.5 15 11 9.8 22 14 13 12 13 9.8 16 13 10 10 11 205 42 17 18 686.8 22.2 205 6.9 1360 1.46 1.68 - 1992 33.5 53.8 1990 22.2 1992 1991 CALENDAR YEAR 13078. 35. 679 8. 9. 25940 2. 32. 69 17 11 3 8 Feb 18 X 6 Nov 15 4 May 29 36 01 18 21 15 14 12 11 13 26 37 26 24 16 10 11 9.5 10 12 32 93 16 15 8.2 9.4 10 11 9.9 10 9.5 838 224 1571.5 52.4 838 8.2 3120 3.45 3.85 307 218 27 19 16 126 23 16 21 39 22 14 13 12 13 167 27 111 105 34 143 20 278 200 56 616 72 38 74 122 73 3022 97.5 616 12 5990 6.41 7.40 146 45 25 46 50 54 304 209 58 44 20 23 15 29 19 15 13 13 13 13 25 14 12 12 12 11 11 11 12 9.9 ___ 1283.9 42.8 304 9.9 2550 2.82 3.14 9.8 9.8 10 17 10 9.9 8.6 102 115 13 47 9.9 45 89 45 20 120 12 11 172 33 30 14 121 22 15 246 75 28 17 177 1654.0 53.4 246 8.6 3280 3.51 4. OS 53 62 23 27 247 38 47 17 241 195 36 23 26 368 45 32 17 15 15 17 336 70 92 28 23 25 25 23 20 42 91 2319 74.8 368 IS 4600 4.92 5.68 27 18 17 18 22 112 35 31 27 26 39 22 24 25 28 30 88 25 51 125 42 20 164 28 20 17 15 15 16 178 1305 43.5 178 IS 2590 2.86 3.19 , BY WATER YEAR (WY) 49.7 87.9 1988 31.6 1991 FOR 1992 16647 45 838 6 7 5840 17 33020 2 40 113 17 9 51.5 97.5 1992 30.8 1989 WATER YEAR .0 .5 Apr 29 .9 Mar 1 .8 Feb 26 Apr 29 .73 Apr 29 .99 .74 .7 40.7 78.1 1989 23.0 1991 41.1 55. 0 1989 24.8 1990 WATER 46 S3 41 1830 6 7 8640 20 33880 3 41 104 21 12 61. S 84.2 1988 22.6 1990 YEARS 1988 - .8 .4 .4 Sep 18 .9 Mar 1 .8 Feb 26 Jun 17 .77 Jun 17 .08 .81 74.2 ISO 1989 32.6 1991 1992 1989 1990 1989 1992 1992 1970 1970 POP t-Uf. RIO PUERTO NUBVO BASIN 50049100 RIO PIBDRAS AT HATO RBY, PR--Continued WATER-QUALITY RECORDS PERIOD OP RECORD.--Water year* 1971 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DIS- PH CHARGE, SPB- WATER INST. CIFIC WHOLE CUBIC CON- FIELD TEMPER- TUR- PEBT DUCT- (STAND- ATURB BID- DATE TIME PER ANCB ARD WATER ITY SECOND (US/CM) UNITS) (DBG OCT 07 DEC 11 PBB 10 MAY 04 JUN 22 AUG 12 1991 1992 . . . DATE OCT 1991 07.. . DEC 11... PBB 1992 10... MAY 04... JUN 22.. . AUG 12.. . DATE OCT 1991 07.. . DEC 11. .. PBB 1992 10.. . MAY 04.. . JUN 22... AUG 12... 1505 11 1250 12 1245 9 1235 21 1500 4 1205 22 HARD- NESS TOTAL (MG/L AS CAC03 ) 170 -- -- 160 -- 160 PLUO- RIDB, DIS- SOLVED (MG/L AS P) 0.10 -- -- 0.20 -- 0.20 .1 .3 CALCIUM DIS- SOLVED (MG/L AS CA) 49 -- -- 46 -- 44 SILICA, DIS- SOLVED (MG/L AS SI 02) 33 -- -- 25 -- 25 457 372 436 500 396 450 MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) 12 -- -- 12 -- 12 SOLIDS, SUM OP CONSTI- TUENTS, DIS- SOLVED (MG/L) 282 -- -- 284 -- 259 8.0 31 7.2 26 C) (NTU) .0 1.4 .5 4.6 7.1 26.5 15 7.5 29 7.6 30 7.7 29 SODIUM, DIS- SOLVED (MG/L AS NA) 31 -- -- 30 -_ 26 SOLIDS, DIS- SOLVED (TONS PER DAY) 8.21 -_ -- 15.9 __ 15.4 .5 13 .0 2.0 .0 10 SODIUM AD- SORP- TION RATIO 1 -- _- 1 __ 0.9 RESIDUE TOTAL AT 105 OXYGEN, OXYGEN COLI- DIS- DEMAND, FORM, STREP- SOLVED CHEM- FECAL, TOCOCCI OXYGEN, (PER- ICAL 0.45 FECAL, DIS CENT (HIGH UM-MF (COLS. SOLVED SATUR- LEVEL) (COLS./ PER (MG/L) ATION) (MG/L) 100 6 5 6 6 6 5 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 3.5 -- -- 4.1 -_ 3.7 NITRO- GEN, DBG. C, NITRATE SUS- PENDED (MG/L) 6 1 1 24 10 25 TOTAL (MG/L AS N) 0.730 0.600 0.790 0.680 0.570 0.760 .4 .3 .3 .0 .4 .7 ALKA- LINITY WAT WH TOT PET FIELD MG/L AS CAC03 160 100 160 160 150 140 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.120 0.090 0.060 0.070 0.070 0.070 84 86 83 87 89 85 SULPIDB TOTAL (MG/L AS S) <0.5 -- -- <0.5 -- - - NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 0.850 0.690 0.850 0.750 0.640 0.830 ML) 100 ML) 20 49000 5200 <10 K12000 3600 22 36000 4400 24 K88000 K11000 18 K110000 K18000 <10 290000 35000 SULFATB DIS- SOLVED (MG/L AS S04) 22 -- -- 29 -- 26 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.460 0.300 0.180 0.590 0.290 1.20 CHLO- RIDE, DIS- SOLVED (MG/L AS CL) 35 -- -- 42 -- 32 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.44 0.50 0.42 0.41 0.51 0.80 K = non-ideal count RIO PUERTO NOEVO BASIN 50049100 RIO PIEDRAS AT HATO REY, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 203 DATE OCT 1991 07.. . DEC 11.. . FEB 1992 10.. . MAY 04.. . JUN 22.. . AUG 12... DATE OCT 1991 07.. . DEC 11.. . FEB 1992 10. .. MAY 04.. . JUN 22. .. AUG 12.. . NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.90 0.80 0.60 1.0 0.80 2.0 IRON, TOTAL RECOV- ERABLE (UG/L AS FE) 440 -- -- 710 -- -- NITRO- GEN, TOTAL (MG/L AS N) 1.7 1.5 1.5 1.7 1.4 2.8 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) 2 -- -- 2 -- -- NITRO- GEN, TOTAL (MG/L AS N03) 7.7 6.6 6.4 7.7 6.4 13 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) 110 -- -- 110 -- -- PHOS- PHORUS ARSENIC TOTAL TOTAL (MG/L (UG/L AS P) AS AS) 0.350 2 0.290 0.320 0.280 2 0.260 0.410 MERCURY TOTAL SELE- RECOV- NIUM, ERABLE TOTAL (UG/L (UG/L AS HG) AS SE) <0.10 <1 __ __ <0.10 <1 __ __ BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) 200 -- -- 200 -- -~ SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) 3 -- -_ 1 -- -- BORON, TOTAL RECOV- ERABLE (UG/L AS B) <10 -- -- 50 -- - - ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) <10 -- -- <10 -- -- CHRO- CADMIUM MIUM, TOTAL TOTAL RECOV- RECOV- ERABLE ERABLB (UG/L (UG/L AS CD) AS CR) <1 <1 __ __ <1 <1 __ _ - - _ CYANIDE TOTAL PHENOLS (MG/L TOTAL AS CN) (UG/L) 0.060 1 __ __ •eO.010 3 __ __ COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) 10 -- -- <10 -- ~- METHY- LENB BLUE ACTIVE SUB- STANCE (MG/L) 0.09 -- -_ 0.13 -- -- 204 RIO PUERTO NUBVO BASIN 50049820 LACUNA SAN JOSB NO. 2 AT SAN JUAN, PR WATER-QUALITY RECORDS LOCATION.--Lat 180 25'46", long 660 02'10", 0.2 mi (0.3 km) east of Cafio de Martin Pefia, and 650 ft (200 m) south of Isla Guachinango. DRAINAGE AREA.--Indeterminate. PERIOD OF RECORD.--Water years 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 NOV 01 JAN 02 MAR 03 MAY 21 JUL 10 SEP 03 NOV 01 JAN 02 MAR 03 MAY 21 JUL 10 SEP 03 K = DATE TIME 1991 1005 1992 0910 0825 1230 0755 1215 ALKA- LINITY WAT WH TOT PET FIELD DATE MG/L AS CAC03 1991 180 1992 110 130 64 370 70 non- ideal count SPE- CIFIC CON- DUCT- ANCE (US /CM) 32000 23000 26700 22700 21000 24000 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 10 14 12 13 16 43 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.5 7.1 7.1 7.2 8.6 8.0 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.020 0.010 <0.010 <0.010 0.010 0.020 TEMPER- ATURE WATER (DBG C) 28.5 25.0 25.5 31.0 28.5 20.0 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) <0.050 <0.050 <0.050 <0.050 <0.050 <0.050 TRANS- PAR- ENCY (SBCCHI DISK) (IN) 19.9 13.8 37.2 24.0 19.0 23.0 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.710 1.70 2.90 0.030 0.060 0.940 OXYGEN, DIS- SOLVED (MG/L) 3.7 0.4 1.8 11.0 6.0 1.2 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.59 0.0 0.80 -- 0.84 0.96 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 48 16 21 144 69 20 NITRO- GEN, AM- MONIA * ORGANIC TOTAL (MG/L AS N) 1.3 1.1 3.7 <0.20 0.90 1.9 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 32000 48000 31000 310 33000 K22000 PHOS- PHORUS TOTAL (MG/L AS P) 0.460 0.300 0.790 0.050 0.130 0.260 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 7100 8300 17000 K10 -- 90 CARBON, ORGANIC TOTAL (MG/L AS C) 7.8 8.1 6.8 10 13 12 RIO PUERTO NUEVO BASIN 205 50049920 BAHIA DE SAN JUAN NO. 5 AT SAN JUAN, PR WATER-QUALITY RECORDS LOCATION--La t 18°26'37", long 66°05'H", 0.4 ml (0.6 km) west of Puente de la Const! tuci [n, and 0.5 mi (0.8 km) south from U.S. Naval Reservation. DRAINAGE--Indeterminate. PERIOD OP RECORD--Water years 1974 to present. WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 PH OXYGEN, COLI- ALKA- RESIDUE SPB- WATER TRANS- DIS- FORM, STREP- LINITY TOTAL CIPIC WHOLE PAR- SOLVED FECAL, TOCOCCI WAT WH AT 105 CON- FIELD TEMPER- BNCY OXYGEN, (PER- 0.45 FECAL, TOT PET DBG. C, DUCT- (STAND- ATURB (SBCCHI DIS- CENT UM-MF (COLS. FIELD SUS- DATB TIME ANCB ARD WATER DISK) SOLVED SATUR- (COLS./ PER MG/L AS P ENDED (US/CM) UNITS) (DBG C) (IN) (MG/L) ATION) 100 ML) 100 ML) CACO3 (MG/L) NOV 1991 04... 1145 36000 7.4 28.5 29.0 2.7 42 37000 5200 120 25 JAN 1992 02... 1010 48000 8.0 26.5 23.4 2.2 39 24000 K7300 120 29 MAR 02... 1130 50000 7.9 26.5 20.8 3.7 52 58000 4900 130 26 MAY 22... 1000 33000 7.5 29.0 17.0 4.4 57 K60000 20000 130 63 JUL 10... 0850 45000 7.1 28.0 28.9 1.0 25 -- K120000 190 30 SEP 03... 1345 50000 8.3 29.0 41.5 6.0 59 330 10 120 35 NITRO- NITRO- NITRO- NITRO- NITRO- NITRO- GEN, AM - GEN, GEN, GEN, GEN, GEN, MONIA 4- NITRO- NITRO- PHOS- CARBON, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC ORGANIC GEN, GEN, PHORUS ORGANIC TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L AS N) AS N) AS N) AS N) AS N) AS N) AS N) AS NO3) AS P) AS C) NOV 1991 04.. . JAN 1992 02... MAR 02.. . MAY 22... JUL 10. .. SEP 03.. . 0. 0. - 0. 0. - 100 070 - 150 090 - 0. 0. 0. 0. 0. <0. 030 030 020 040 030 010 0. 0. <0. 0. 0. <0. 130 100 050 190 120 050 0 0 0 0 1 0 .630 .260 .680 .470 .20 .030 0 0 0 0 0 - .17 .04 .32 .43 .0 - 0.80 0.30 1.0 0.90 1.2 <0.20 0.93 0.40 -- 1.1 1.3 -- 4.1 1.8 -- 4.8 5.8 — 0. 0. 0. 0. 0. 0. 190 060 210 200 260 100 5.7 3.0 6.2 6.2 7.9 2.5 non-ideal count 206 THIS PAGE WAS LEFT BLANK INTENTIONALLY ATLANTIC / 0603 \V Ci.<5«>a Si;.*,* ,' W 1 207 *'Y jr> \\ / ( ': i Xc' \ 051800 051180 S —^ A iWM^». * e! X i "7^ \ „ . ^-; K. 051310 -r—-'" ,> \ / /—0">'n a3« "5'>"'"'0- 051150 ^J A -v, , '•• \.- H rl \ i, ! v—^ (\ \r- ^ .-•?/ <^ -v ,'r -—— / Xfl.^ «»10r « 0.J • U3i"< *»i » "umcfftn B0» f •n..- ,.X ..—x/ v~<^Ct-" /"--v V /" "-/ y.«»OtU.t« i»Rt- ;',!-: "VI3 M <|-!*O-;. »A* J'JiS « ii 0509 _ __^./ O> "'"" f'J;',''A--. ,' ^ S - ",,.../xv=-.- : - 5 , ' ^-.f-,rt :-, - V 01 23456 KILOMETERS L. . ,. .:..... 0 1 2 EXPLANATION SURFACE-WATER STATION A 0509 AND NUMBER w 0554 QUALITY-OF-WATER STATION T AND NUMBER V7 ncsyc; QUALITY-OF-WATER V U5/& PARTIAL RECORD STATION AND NUMBER WELL NUMBER 0590 LAKE-ELEVATION STATION Figure 20r-Rio Grande de Loiza basin. 208 RIO GRANDB DB LOIZA BASIN 50050300 QUBBRADA BLASINA NEAR CAROLINA, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°23'2V, long 65°58'28", at bridge on Highway 3, 1.4 mi (2.3 km) couth of Vi Height* housing area, and 1.2 mi (1.9 km) wett-couthwett of Carolina plaza. DRAINAGE AREA.--2.96 mi 1 (7.67 km>). PERIOD OF RBCORD.—Water year* 1973 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 lie Arriba DATE OCT 1991 16. .. DEC 26. .. FBB 1992 12. .. MAY 11. .. JUN 22... AOG 17... TIME 0955 1135 1050 0900 1045 1300 DIS- CHARGE, INST. CUBIC FEET PER SECOND 6.4 4.1 4.8 7.2 8.3 6.6 SPE- CIFIC CON- DUCT- ANCE (US/CM) 430 443 460 470 395 385 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.8 7.5 7.2 6.9 7.0 7.4 TEMPER- ATURE WATER (DBG C) 26.0 23.5 24.0 26.0 29.0 28.5 TUR- BID- ITY (NTU) 27 25 190 2.5 19 22 OXYGEN, DIS- SOLVED (MG/L) 2.0 5.3 6.1 4.5 7.3 6.2 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 25 37 42 55 48 36 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 31 23 60 25 25 20 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K68000 43000 K71000 230000 25000 59000 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 20000 62000 4400 K8500 3900 5600 OCT 1991 16... DEC 26... FBB 1992 12... MAY 11... JUN 22... AUG 17... HARD- NESS CALCIUM TOTAL DIS- (MG/L SOLVED AS (MG/L MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L CACO3) AS CA) AS MG) AS NA) 160 52 150 46 140 44 8.4 29 9.5 32 6.9 21 SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY SIUM, WAT WH DIS- TOT FBT SULFIDB SOLVED FIELD TOTAL (MG/L MG/L AS (MG/L AS K) 3.8 3.6 0.8 2.8 CACO3 140 150 180 140 140 160 SULFATB DIS- SOLVED (MG/L <0.5 30 <0.5 22 32 CHLO- RIDE, DIS- SOLVED (MG/L AS S) AS S04) AS CL) 35 45 29 DATE OCT 1991 16... DEC 26... FBB 1992 12... MAY 11... JUN 22... AUG 17... FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.10 -- -- 0.20 -- 0.40 SILICA, DIS- SOLVED (MG/L AS SI02) 23 — — 26 — 16 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 265 -- -- 268 -- 224 SOLIDS, DIS- SOLVED (TONS PER DAY) 4.56 -- -- 5.22 -- 3.55 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 49 24 390 <1 37 98 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.750 1.03 1.14 0.720 0.930 0.750 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.080 0.170 0.160 0.210 0.070 0.060 NITRO- GEN, N02+N03 TOTAL (MG/L AS N) 0.830 1.20 1.30 0.930 1.00 0.810 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.280 0.580 0.390 0.740 0.150 0.160 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 1.1 0.82 1.9 0.86 0.45 0.64 non-ideal count RIO GRANDB DB LOIZA BASIN 50050300 QDBBRADA BLASINA NEAR CAROLINA, PR—Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 209 DATE OCT 1991 16.. . DEC 26.. . PBB 1992 12... MAY 11.. . JUN 22.. . AUG 17.. . DATE OCT 1991 16. .. DEC 26.. . PBB 1992 12. .. MAY 11. . . JUN 22.. . AUG 17. .. NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 1.4 1.4 2.3 1.6 0.60 0.80 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) 890 -- -- 270 -- -- NITRO- GEN, TOTAL (MG/L AS N) 2.2 2.6 3.6 2.5 1.6 1.6 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) 4 -- -- <1 -- -- NITRO- GEN, TOTAL (MG/L AS N03) 9.9 12 16 11 7.1 7.1 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MM) 460 -- -- 210 -- -- PHOS- PHORUS TOTAL (MG/L AS P) 0.700 0.450 0.720 0.390 0.160 0.290 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) 0.10 -- -- <0.10 -- -- BARIUM, TOTAL ARSENIC RECOV- TOTAL BRABLB (UG/L (UG/L AS AS) AS BA) <1 <100 __ __ 2 <100 __ — — - - SILVER, SBLB- TOTAL NIUM, RECOV- TOTAL BRABLB (UG/L (UG/L AS SB) AS AG) <1 <1 __ __ 1 <1 __ __ BORON, TOTAL RECOV- ERABLE (UG/L AS B) 30 -- -- 60 -- - - ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) 10 -- -- <10 -- -- CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 -- -- <1 -- - - CYANIDE TOTAL (MG/L AS CN) <0.010 -- -- <0.010 -- -- CHRO- MIUM, COPPER, TOTAL TOTAL RBCOV- RECOV- ERABLE BRABLB (UG/L (UG/L AS CR) AS CU) 4 20 __ __ <1 <10 __ - - — — MBTHY- LENB BLUB ACTIVE PHENOLS SUB- TOTAL STANCE (UG/L) (MG/L) 2 0.08 __ -_ 2 0.12 __ __ 210 RIO GRANDE DE LOIZA BASIN 50050900 RIO GRANDE DB LOIZA AT QOBBRADA ARENAS, PR LOCATION. --Lat 18°07'10", long 65°59'22", Hydrologic Unit 21010005, at intersection of Highways 181 and 9990, 0.2 mi (0.3 km) upstream from confluence with Rio Bmajagua and about 7.1 mi (11.4 km) southwest of San Lorenzo. DRAINAGE AREA.--6.00 mi* (15.54 km*). HATER-DISCHARGE RECORDS PERIOD OF RECORD.--October 1977 to current year. GAGE.—Water-stage recorder. Elevation of gage is 640 ft (195 m), from topographic map. REMARKS.--Records fair except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 24 8.9 2 75 9.2 3 24 8.8 4 18 16 5 18 11 6 15 11 7 13 237 8 12 e840 9 18 elSO 10 13 78 11 14 34 12 33 30 13 IS 23 14 12 19 IS 12 17 16 13 IS 17 15 14 18 11 13 19 11 12 20 10 12 21 9.4 eSS 22 9.S e70 23 11 e20 24 10 e80 25 9.4 e3S 26 9.7 e20 27 9.7 e4S 28 9.7 e3S 29 9.3 e30 30 9.0 e20 31 8.8 - — TOTAL 481. 5 1968.9 MEAN IS. 5 65. 6 MAX 75 840 MIN 8.8 8.8 AC-FT 955 3910 CFSM 2. 59 10.9 IN. 2.99 12.21 e Estimated e!8 e!7 e!8 e25 e!8 elS e!4 e!3 e!4 e!2 ell ell e!2 10 9.7 13 10 9.4 9.1 16 12 9.0 9.1 8.6 8.6 e8.4 e8.3 e8.4 e9.0 ell e!2 379.6 12.2 25 8.3 753 2.04 2. 35 STATISTICS OF MONTHLY MEAN DATA MEAN 43.6 48.4 MAX 123 122 (WY) 1986 1988 MIN 13.1 8.34 (WY) 1990 1990 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN- DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS SO PERCENT EXCEEDS 90 PERCENT EXCEEDS 24.7 SS.2 1988 6.65 1990 FOR elO •9.0 •8.4 •8.0 elOOO •200 • 60 43 32 33 28 24 21 19 22 18 17 16 IS IS 14 13 14 14 14 14 13 13 11 11 11 1740.4 56. 1 1000 8.0 34SO 9.36 10.79 11 10 10 11 11 24 14 13 12 13 12 12 11 14 15 13 11 12 11 11 10 11 11 12 11 IS 14 12 9.4 ___ --- 356. 4 12.3 24 9.4 707 2. OS 2.21 FOR WATER YEARS 1978 18.3 56. 1 1992 8.16 1990 16.8 38.0 1982 6.36 1979 8.S 9.5 9.1 9.1 8.8 8.8 22 •20 e!2 e8.0 6.6 6.2 6.3 6.4 7.3 5.9 •8.0 •9.0 6.2 6.2 5.7 6.1 5.9 5.8 5.7 6.0 S.4 5.2 5.2 5.3 e6.S 246.7 7.96 22 S.2 489 1.33 1.S3 - 1992 12.7 33.1 1989 5.07 1979 1991 CALENDAR YEAR 724S.2 19.8 840 4.5 4.7 14370 3.31 44.92 26 10 6.1 Nov 8 Apr 30 Apr 27 •8.0 •8.2 •6.0 •5.8 •5.6 •5.4 •5.6 •6.4 • 6.2 • 6.0 elO •15 ell •13 elO •9.0 •7.0 • 6.6 •8.0 •20 •13 •8.0 •7.4 •6.4 • 6.0 •5.4 •5.2 eS.O eS.O eS.4 --- 239.6 7.99 20 S.O 475 1.33 1.49 •6.0 • 15 •13 •7.0 •6.4 •20 • 13 elO •8.0 •6.6 e6.0 •7.0 eS.O e9.0 •8.0 •30 • 13 • 12 •12 11 11 11 •150 •300 eSO •350 •60 e30 e22 •35 •22 1262.0 40.7 350 6.0 2500 6.78 7.82 •80 •70 •27 • 140 •40 •30 •27 •29 •31 •60 •62 • 150 elOO •80 •45 •37 •60 •35 •25 •22 • 150 •35 30 26 23 21 20 18 17 16 1506 50.2 ISO 16 2990 8.37 9.34 15 14 13 13 18 13 12 18 IS 13 33 15 13 15 14 12 31 15 18 19 20 101 18 15 48 16 13 11 10 10 9.8 600.8 19.4 101 9.8 1190 3.23 3.72 12 13 12 13 • 150 •50 •20 •17 •30 •20 •18 •15 14 44 20 19 17 15 15 16 14 13 15 16 14 16 15 18 16 16 22 705 22.7 150 12 1400 3.79 4.37 21 18 27 17 15 18 16 26 56 26 17 IS 15 13 12 19 50 49 75 24 • 19 •17 • 15 • 14 •13 •12 ell ell ell •12 664 22.1 75 11 1320 3.69 4.12 , BY WATER YEAR (WY) 13.1 27.1 1985 4.64 1979 FOR 1992 10150 27 1000 5 5 4810 10 20130 4 62 44 13 6 34.2 77.5 1985 9.56 1988 WATER YEAR .9 .7 Jan S .0 Apr 28 .4 Apr 25 Nov 8 .76 Nov 8 .62 .94 .6 37.9 122 1979 11.3 1985 34.6 82.2 1979 12.5 1986 WATER 29 49 14 1250 3 3 11700 14 2 21150 4 66 49 15 6 29.8 90.0 1979 9.30 1991 YEARS 1978 .2 .6 .5 Oct .1 May .6 May Nov .78 Nov .8 May .87 .11 .9 35.6 94.3 1979 11.8 1981 - 1992 1979 1990 6 1985 7 1979 1 1979 5 1983 5 1983 5 1979 211 RIO GRANDS DB LOIZA BASIN 50050900 RIO GRANDS DB LOIZA AT QOEBRADA ARENAS, PR--Continued WATER QUALITY RECORDS PERIOD OP RECORD.--WATER YEARS AUGUST 1981 TO CURRENT YEAR STREAMFLOW, SPECIFIC CON- TEMPERA- STREAM?LOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCE TURE DATE TIME INSTANTANEOUS DOCTANCB TURE (CFS) (UMHOS) (DBG C) (CFS) (DMHOS) (DBG C) JAN. 28 1438 13.9 150 27.0 JUN. 22 1152 39.2 110 25.5 FEB. 18 1452 11.6 160 26.5 JUL. 08 1132 16.4 130 27.0 MAR. 26 1247 6.88 150 27.0 AUG. 12 1305 13.6 120 27.0 MAY. 20 1348 11.1 110 27.5 212 RIO GRANDB DB LOIZA BASIN 50051150 QOBBRADA BLANCA AT BL JAGOAL, PR LOCATION.--Lat 18°09'40", long 65°58'58", Hydrologic Unit 21010005, 0.1 mi (0.2 km) upstream from bridge on Highway 181, and 2.8 mi (4.5 km) southwest of San Lorenco. DRAINAGE AREA.--3.25 mi' (8.42 km 1 ). HATER-DISCHARGE RECORDS PERIOD OF RECORD.--October 1984 to current year. GAGE.--Water-stage recorder and crest-stage gage. Elevation of gage is 459 ft (140 m), from topographic map. REMARKS.--Records fair. Gage-height and precipitation satellite telemetry at station. DAY DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES OCT NOV DEC JAN FBB APR MAY JUN JUL STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1984 - 1992, BY WATER YEAR (WY) MEAN MAX (WY) MIN (WY) 13.0 47.8 1986 3.20 1987 19.7 36.9 1985 2.49 1990 7.90 30.1 1988 1.49 1990 4.82 9.94 1992 1.79 1990 4.04 8.21 1989 1.32 1985 4.65 20.7 1989 1.76 1992 2.53 4.88 1989 .90 1991 9.41 31.5 1985 1.51 1990 6.20 21.3 1987 2.40 1991 5.03 13.0 1988 2.02 1986 AUG 6.44 20.2 1988 2.21 1985 SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC -FT CFSM IN. 11 31 11 5.6 4.2 3.1 2.5 2.1 1.9 1.6 1.9 1.4 1.6 2.0 2.0 2.6 3.1 3.0 2.1 1.6 1.4 1.5 1.7 1.5 1.4 1.4 1.4 1.4 1.6 1.6 1.5 111.7 3.60 31 1.4 222 1.11 1.28 1.5 1.5 1.6 3.4 2.7 7.8 41 114 60 39 24 16 11 7.5 5.8 27 16 7.7 5.6 4.5 16 33 15 53 30 15 31 41 28 18--- 677.6 22.6 114 1.5 1340 6.95 7.76 13 9.9 14 12 7.9 6.3 5.4 4.8 3.9 3.2 3.0 3.3 2.5 3.2 2.1 2.7 2.1 1.7 1.5 5.8 3.7 1.8 1.5 1.3 1.2 1.1 1.0 .92 .93 .96 1.8 124.51 4.02 14 .92 247 1.24 1.43 1.4 .95 .81 .72 194 55 7.5 5.9 4.1 3.6 2.6 2.1 1.8 1.7 1.5 1.6 2.2 1.5 1.3 1.2 1.2 1.1 1.1 1.3 1.4 1.5 1.5 1.9 1.9 1.8 2.0 308.18 9.94 194 .72 611 3.06 3.53 2.1 2.1 2.3 3.9 3.3 7.3 8.8 5.3 5.5 7.7 5.7 4.8 4.3 3.8 4.1 4.0 3.6 3.4 3.4 3.4 3.2 3.1 3.1 4.1 3.6 3.1 2.9 2.6 2.4 ___ --- 116.9 4.03 8.8 2.1 232 1.24 1.34 2.3 2.5 2.6 2.4 2.4 2.7 2.5 2.3 2.1 2.0 1.8 1.8 1.7 1.7 1.7 1.6 2.0 1.9 1.7 1.5 1.5 1.4 1.4 1.2 1.2 1.2 1.1 1.1 1.1 1.1 1.2 54.7 1.76 2.7 1.1 108 .54 .63 1.3 1.1 1.1 1.1 1.1 1.2 1.5 1.3 1.1 1.0 1.5 1.9 1.4 1.4 1.4 1.3 1.2 1.2 1.3 1.5 1.4 1.6 1.5 1.4 1.4 1.5 1.6 1.5 1.5 1.7 --- 41.0 1.37 1.9 1.0 81 .42 .47 2.7 5.3 2.1 1.8 1.5 2.3 2.8 2.0 1.7 1.6 1.8 2.0 1.6 1.6 2.0 20 8.0 6.2 6.9 19 14 12 60 42 16 34 13 7.4 6.6 6.2 4.0 308.1 9.94 60 1.5 611 3.06 3.53 12 8.5 5.2 31 8.1 4.5 4.8 6.1 4.5 12 7.0 32 13 14 11 10 10 6.6 4.2 5.6 30 12 7.2 5.1 3.9 3.6 3.4 2.9 2.4 2.3 --- 282.9 9.43 32 2.3 561 2.90 3.24 2.2 2.0 2.1 7.0 10 2.7 2.3 5.7 4.0 2.4 4.9 3.4 2.2 1.9 2.1 3.9 20 3.1 2.5 4.0 4.3 18 3.6 4.5 12 5.4 4.7 3.9 3.2 2.7 2.5 153.2 4.94 20 1.9 304 1.52 1.75 2.5 3.2 3.3 4.1 51 14 7.2 4.3 3.8 7.2 4.4 8.7 5.1 4.6 4.3 3.5 3.1 2.5 2.2 2.0 1.9 1.8 1.7 2.2 2.1 2.0 2.2 1.9 1.7 1.6 3.7 163.8 5.28 51 1.6 325 1.63 1.87 2.0 1.6 4.0 2.5 1.6 1.9 1.8 1.6 3.9 1.8 1.6 1.6 1.6 1.7 1.7 11 13 7.7 28 57 26 11 8.5 4.8 3.1 2.3 1.9 1.6 1.4 1.3 --- 209.5 6.98 57 1.3 416 2.15 2.40 7.68 14.3 1985 1.36 1990 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK PLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS FOR 1991 CALENDAR YEAR 1958.48 5.37 114 Nov 8 .38 Aug 10 .42 Aug 7 3880 1.65 22.42 14 1.8 .60 FOR 1992 WATER YEAR WATER YEARS 1984 - 1992 2552.09 6.97 194 .72 1.1 7180 14.30 .65 5060 2.15 29.21 14 2.5 1.3 Jan Jan Dec Jan Jan Jan 5 4 24 5 5 5 7 12 2 457 7400 14 5530 2 31 13 2 1 .63 .3 .50 .38 .42 .58 .35 .89 .5 .1 Dec Aug Aug May May 7 10 7 17 17 1988 1990 1987 1991 1991 1985 1985 RIO GRANDB DB LOIZA BASIN 50051150 QUBBRADA BLANCA AT EL JAGUAL, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORDS.-- Water years 1985 to 1986 and water year 1989 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: October 1984 to September 1986 and from October 1989 to September 1992. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATIONi Maximum daily mean, 7,300 mg/L Oct. 06, 1985; Minimum daily mean, 1 mg/L several days. SEDIMENT LOADS: Maximum daily mean, 4,940 tons (23,400 tonnes) May 17, 1985; Minimum daily mean, 0.0 ton (0.0 tonne) several days. EXTREMES FOR WATER YEARS 1992.-- SBDIMENT CONCENTRATIONi Maximum daily mean, 1,150 mg/L Nov. 08, 1991; Minimum daily mean, 1 mg/L several days. SEDIMENT LOADS: Maximum daily mean, 2,440 tons (2,210tonnes) Jan. 05, 1992; Minimum daily mean, 0 ton several days. 213 SBOIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CFS) 11 31 11 5.6 4.2 3.1 2.5 2.1 1.9 1.6 1.9 1.4 1.6 2.0 2.0 2.6 3.1 3.0 2.1 1.6 1.4 1.5 1.7 1.5 1.4 1.4 1.4 1.4 1.6 1.6 1.5 MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) OCTOBER 33 193 25 16 14 13 11 8 8 7 7 6 6 6 6 6 6 6 5 4 3 3 3 3 3 2 2 2 2 2 2 1.3 27 .86 .25 .16 .10 .07 .05 .04 .04 .03 .02 .03 .04 .04 .04 .05 .04 .03 .02 .02 .02 .01 .02 .02 .01 .00 .00 .00 .00 .00 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) NOVEMBER 1 1 1 3 2 7 41 114 60 39 24 16 11 7 5 27 16 7 5 4 16 33 15 53 30 15 31 41 28 18 .5 .5 .6 .4 .7 .8 .5 .8 .7 .6 .5 2 2 2 6 4 22 292 1150 350 36 22 14 9 5 2 125 42 9 9 9 63 184 38 357 114 18 145 240 62 15 52 634 66 4 1 26 2 12 20 1 70 10 16 45 5 .00 .00 .01 .08 .04 .88 .1 .5 .61 .27 .10 .04 .5 .19 .14 .11 .6 .77 .2 .71 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) DECEMBER 13 9.9 14 12 7.9 6.3 5.4 4.8 3.9 3.2 3.0 3.3 2.5 3.2 2.1 2.7 2.1 1.7 1.5 5.8 3.7 1.8 1.5 1.3 1.2 1.1 1.0 .92 .93 .96 1.8 12 7 7 11 10 7 5 4 3 4 5 6 6 6 6 9 10 9 7 4 5 5 6 7 10 11 7 3 3 6 11 .41 .20 .30 .34 .20 .12 .08 .05 .03 .03 .04 .06 .04 .06 .04 .07 .05 .04 .03 .05 .06 .02 .02 .02 .02 .03 .02 .00 .01 .02 .06 TOTAL 111.7 30.31 677.6 969.85 124.51 2.52 214 RIO GRANDE DE LOIZA BASIN 50051150 QDEBRADA BLANCA AT EL JAGOAL, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN DISCHARGE (CPS) 1.4 .95 .81 .72 194 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 55 7.5 5.9 4.1 3.6 2.6 2.1 1.8 1.7 1.5 1.6 2.2 1.5 1.3 1.2 1.2 1.1 1.1 1.3 1.4 1.5 1.5 1.9 1.9 1.8 2.0 MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) JANUARY 16 20 19 17 1020 649 13 7 6 6 5 4 3 2 3 3 4 3 3 2 2 2 2 2 17 4 5 6 4 2 3 .06 .04 .04 .04 2440 154 .28 .11 .08 .06 .04 .03 .01 .01 .02 .02 .03 .02 .02 .01 .00 .00 .00 .00 .06 .02 .02 .03 .02 .02 .02 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) PEBRDARY 2.1 2.1 2.3 3.9 3.3 7.3 8.8 5.3 5.5 7.7 5.7 4.8 4.3 3.8 4.1 4.0 3.6 3.4 3.4 3.4 3.2 3.1 3.1 4.1 3.6 3.1 2.9 2.6 2.4 .02 .02 .02 .03 .01 .04 .07 .05 .04 .06 .05 .04 .04 .03 .02 .01 .00 .00 .00 .00 .00 .01 .02 .02 .03 .02 .02 .02 .02 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) MARCH 2.3 2.5 2.6 2.4 2.4 2.7 2.5 2.3 2.1 2.0 1.8 1.8 1.7 1.7 1.7 1.6 2.0 1.9 1.7 1.5 1.5 1.4 1.4 1.2 1.2 1.2 1.1 1.1 1.1 1.1 1.2 .02 .01 .01 .02 .02 .02 .02 .02 .02 .02 .01 .00 .01 .02 .02 .02 .03 .04 .04 .03 .02 .02 .01 .01 .02 .02 .01 .00 .01 .02 .02 TOTAL 308.18 2595.11 116.9 0.71 54.7 0.56 RIO GRANDS DB LOIZA BASIN 215 50051150 QUBBRADA BLANCA AT EL JAGOAL, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 1.3 1.1 1.1 1.1 1.1 1.2 1.5 1.3 1.1 1.0 1.5 1.9 1.4 1.4 1.4 1.3 1.2 1.2 1.3 1.5 1.4 1.6 1.5 1.4 1.4 1.5 1.6 1.5 1.5 1.7 APRIL 4 3 2 3 6 7 6 5 4 3 3 2 2 2 1 1 1 1 2 2 2 2 2 2 2 2 3 3 4 5 .02 .01 .00 .01 .02 .03 .03 .02 .01 .00 .01 .01 .00 .00 .00 .00 .00 .00 .01 .01 .00 .01 .00 .00 .00 .01 .02 .02 .02 .02 ___ MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MAY 2.7 5.3 2.1 1.8 1.5 2.3 2.8 2.0 1.7 1.6 1.8 2.0 1.6 1.6 2.0 20 8.0 6.2 6.9 19 14 12 60 42 16 34 13 7.4 6.6 6.2 4.0 7 13 3 1 2 3 4 4 3 2 1 1 3 5 5 554 23 10 6 159 31 4 462 278 53 310 45 13 6 17 7 .09 .28 .03 .00 .01 .02 .03 .02 .02 .01 .00 .00 .01 .02 .02 81 .55 .16 .12 19 1.4 .14 258 47 2.9 50 1.9 .26 .11 .42 .09 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) JUNE 12 8.5 5.2 31 8.1 4.5 4.8 6.1 4.5 12 7.0 32 13 14 11 10 10 6.6 4.2 5.6 30 12 7.2 5.1 3.9 3.6 3.4 2.9 2.4 2.3 57 26 12 318 34 31 24 15 9 41 22 217 27 34 14 29 12 7 5 9 169 9 6 6 11 15 16 16 14 8 6.8 .78 .17 117 .75 .40 .32 .26 .11 2.5 .55 31 .95 1.5 .39 1.2 .32 .14 .05 .29 25 .30 .12 .08 .10 .16 .15 .11 .08 .05 TOTAL 41.0 0.29 308.1 463.61 282.9 191.63 216 RIO GRANDB DB LOIZA BASIN 50051150 QDBBRADA BLANCA AT BL JAGOAL, PR--Continued SEDIMENT DISCHARGE, SOSFENDED (TONS/DAY), HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 I DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL YEAR MEAN C JISCHARGB 1 (CPS) 2.2 2.0 2.1 7.0 10 2.7 2.3 5.7 4.0 2.4 4.9 3.4 2.2 1.9 2.1 3.9 20 3.1 2.5 4.0 4.3 18 3.6 4.5 12 5.4 4.7 3.9 3.2 2.7 2.5 153.2 2552.09 MEAN :ONCBN- 'RATION MG/L) ( JULY 4 3 3 28 42 7 7 15 4 3 3 4 4 4 5 5 135 10 5 5 5 79 15 8 30 5 ... SEDIMENT DISCHARGE TONS/ DAY) .03 .01 .01 2.3 1.9 .05 .04 .41 .06 .02 .04 .03 .02 .03 .03 .05 19 .08 .04 .05 .06 6.6 .17 .09 1.7 .07 .06 .04 .04 .03 .02 33.08 4876.21 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) AUGUST 2.5 3.2 3.3 4.1 51 14 7.2 4.3 3.8 7.2 4.4 8.7 5.1 4.6 4.3 3.5 3.1 2.5 2.2 2.0 1.9 1.8 1.7 2.2 2.1 2.0 2.2 1.9 1.7 1.6 3.7 4 4 4 6 461 83 27 16 12 8 6 21 8 5 3 2 2 3 6 5 3 2 2 1 2 3 4 6 6 5 3 .02 .04 .05 .10 121 3.9 .53 .20 .13 .15 .10 .73 .11 .08 .04 .02 .02 .03 .04 .03 .02 .01 .00 .00 .01 .01 .02 .03 .03 .02 .02 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) SEPTEMBER 163.8 127.49 2.0 1.6 4.0 2.5 1.6 1.9 1.8 1.6 3.9 1.8 1.6 1.6 1.6 1.7 1.7 11 13 7.7 28 57 26 11 8.5 4.8 3.1 2.3 1.9 1.6 1.4 1.3 209.5 2 2 1 1 1 1 1 2 2 2 1 3 S 5 4 62 45 19 243 329 49 7 3 3 2 2 2 1 1 1 .01 .00 .01 .00 .00 .00 .00 .00 .03 .01 .00 .01 .02 .02 .02 9.2 3.0 .56 32 412 3.8 .19 .08 .04 .02 .02 .01 .00 .00 .00 461.05 RIO GRANDB DB LOIZA BASIN 50051150 QUBBRADA BLANCA AT BL JAGUAL, PR—Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT 217 DATE NOV 1991 08. . . 16. .. 28. .. JAN 1992 05. .. MAY 16. .. JUN 04... TIME 1633 1420 1340 1020 1238 0940 DIS- CHARGE, INST. CUBIC FEET PER SECOND 101 120 111 113 83 341 SEDI- MENT, SUS- PENDED (MG/L) 1230 1130 1190 851 82500 3150 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 335 366 401 260 18500 2900 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM 58 47 -- 54 2 23 SED. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM 60 -- 52 56 3 29 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 70 63 58 59 5 35 DATE SED. SUSP. PALL DIAM. PERCENT FINER THAN .016 MM SBD. SUSP. PALL DIAM. PERCENT FINER THAN .031 MM SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM SED. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM NOV 1991 08. . . 16.. . 28. . . JAN 1992 05. . . MAY 16.. . JUN 04. .. 82 67 65 -- 9 43 86 69 76 74 17 52 96 92 95 96 35 69 98 97 98 98 64 82 99 99 99 99 86 93 99.8 99.7 99.8 99.6 97 98 99.9 99.8 99.9 99.9 99 99 218 RIO GRANDB DE LOIZA BASIN 50051150 QOEBRADA BLANCA AT EL JAGUAL--Continued HATER QUALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 SILT AND CLAY PERCENT OP SUSPENDED SEDIMENT DATE NOV 1991 16... 28... JAN 1992 05... 06... MAY 16.. . JUN 04.. . 04.. . AUG 05. .. 05.. . SEP 19. .. TIME 1455 1410 0955 1343 1258 1035 1125 1015 1858 1635 STREAM- FLOW, INSTAN- TANEOUS (CFS) 120 122 72 37 118 69 70 40 70 97 SEDI- MENT, SUS- PENDED (MG/L) 459 897 662 143 3306 1600 564 52 1970 1530 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 149 296 129 14 1050 299 106 5.6 372 401 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 96 97 97 95 91 95 96 96 95 86 RIO GRANDB DB LOIZA BASIN 50051180 QUBBRADA SALVATIBRRA NEAR SAN LORBNZO, PR 279 LOCATION.--Lat 180 10'24", long 65°58'38', Hydrologic Unit 21010005, on left downstream side of bridge on Highway 181, 0.2 mi (0.3 km) upstream from Rio Grande de Loiia, and 1.5 mi (2.4 km) southwest of San Lorenio. DRAINAGE AREA.--3.74 mi* (9.69 km>). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--January 1984 to current year. QAGB.—Hater-stage recorder and crest-stage gage. Elevation of gage is 330 ft (100 m), from topographic map. REMARKS.--Records fair except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. DAY DISCHARGE, CUBIC FEET PBR SECOND, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES OCT NOV DEC JAN APR MAY JUN JUL e Estimated STATISTICS OF MONTHLY MEAN DATA FOR HATER YEARS 1984 - 1992, BY HATER YEAR (WY) MEAN MAX (HY) MIN (HY) 11.1 36.2 1986 2.31 1987 15.1 33.4 1988 2.72 1990 S.94 22.8 1988 1.17 1990 5.37 23.4 1992 1.16 1990 3.57 10.3 1984 1.23 1990 3.74 17.4 1989 1.15 1992 2.80 6.60 1985 .88 1984 8.58 35.8 1985 1.53 1990 6.56 15.0 1984 1.78 1991 4.30 12.1 1988 1.58 1986 ADG 5.46 14.4 1988 1.95 1985 SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC -FT CFSM IN. 14 21 15 15 9.2 5.1 3.0 2.3 1.6 1.3 3.7 1.4 1.4 1.0 .90 .85 1.2 .79 .73 .60 .53 .53 2.4 .82 .65 .64 .61 .57 2.8 7.7 1.9 119.22 3.85 21 .53 236 1.03 1.19 1.6 1.8 .95 1.2 1.5 9.4 38 209 69 17 10 6.7 3.7 2.3 1.8 4.1 3.1 1.5 1.1 1.1 2.9 8.2 2.6 22 9.1 4.7 11 10 8.9 5.8 --- 470.05 15.7 209 .95 932 4.19 4.68 3.7 2.4 7.2 8.1 4.9 3.1 2.1 1.9 1.7 1.5 1.3 2.1 2.0 2.4 1.8 2.2 2.2 2.1 2.2 4.4 5.2 2.1 1.8 1.4 1.4 1.4 1.4 1.3 1.3 1.3 2.9 80.8 2.61 8.1 1.3 160 .70 .80 2.1 1.7 1.4 1.4 472 169 16 8.3 6.3 5.8 3.9 3.0 2.4 2.0 2.0 2.0 4.2 1.9 1.8 1.8 1.6 1.4 1.4 1.6 1.7 1.7 1.5 1.5 1.6 1.5 1.5 726.0 23.4 472 1.4 1440 6.26 7.22 1.4 1.4 1.4 1.7 1.3 2.3 3.2 1.6 1.4 4.4 2.1 1.5 1.4 1.2 1.4 1.3 1.2 1.2 1.2 1.3 1.3 1.3 1.4 1.7 1.6 1.5 1.4 1.4 1.3 ___ 46.8 1.61 4.4 1.2 93 .43 .47 1.2 1.1 1.1 1.2 1.3 1.4 1.4 1.3 1.1 1.0 1.0 1.0 1.0 1.1 1.5 1.2 1.3 1.5 1.2 1.5 1.1 1.1 1.1 .91 1.0 1.1 1.1 1.0 1.0 .94 .97 35.72 1.15 1.5 .91 71 .31 .36 1.0 1.0 .94 1.1 1.1 .99 1.6 1.6 1.3 1.1 1.5 2.3 1.4 1.2 1.4 1.4 1.1 1.3 1.7 1.1 .84 .90 1.0 .94 1.0 1.1 1.1 1.1 .90 1.4 36.41 1.21 2.3 .84 72 .32 .36 3.1 8.4 2.0 el.l el. 2 el. 8 e2.2 el. 6 el. 4 el. 3 el. 4 el. 5 el. 3 el. 2 el. 2 12 2.7 1.4 1.2 4.7 2.3 1.3 57 60 12 40 8.0 4.4 2.5 2.2 1.6 244.0 7.87 60 1.1 484 2.10 2.43 3.3 3.2 1.6 45 6.8 3.5 3.0 3.3 3.0 4.9 4.5 41 16 11 6.5 6.4 4.7 3.2 2.3 2.3 10 3.5 2.3 2.0 1.8 1.4 1.6 1.6 1.3 1.2 --- 202.2 6.74 45 1.2 401 1.80 2.01 1.2 1.1 1.0 2.4 3.6 1.2 1.0 1.1 1.3 1.0 1.5 1.3 1.1 .99 .93 2.0 6.9 1.8 1.7 2.0 1.8 6.7 2.4 1.7 1.7 1.4 1.4 1.4 1.3 1.2 1.2 57.32 1.85 6.9 .93 114 .49 .57 1.2 1.3 1.2 1.2 64 13 7.5 5.2 3.4 9.0 4.9 6.2 4.7 3.6 3.2 2.5 2.1 2.1 1.8 1.7 1.6 1.5 1.4 e2.5 e2.0 e2.2 e2.0 el. 9 el. 8 el. 7 e3.5 161.9 5.22 64 1.2 321 1.40 1.61 el. 9 el. 6 3.7 e2.5 el. 6 e3.5 e2.5 el. 8 e4.0 2.2 1.7 1.6 1.5 1.5 1.7 2.8 6.3 6.7 54 119 56 20 13 10 9.1 8.9 8.6 7.9 7.2 7.0 369.8 12.3 119 1.5 733 3.30 3.68 10.7 29.0 1989 1.88 1990 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK PLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS FOR 1991 CALENDAR YEAR 1561.29 4.28 FOR 1992 HATER YEAR HATER YEARS 1984 - 1992 209 Nov 8 .33 Jul 13 .49 Jun 14 3100 . 1.14 15.53 8.0 1.4 .65 2550. 6. 472 . . 5240 15. . 5060 1. 25. 9. 1. 1. 22 97 53 75 22 48 86 37 1 7 0 Jan Oct Oct Jan Jan Oct 5 21 16 5 5 29 6.91 10.4 3.19 472 .29 .41 9320 17.10 .26 5010 1.85 25.10 10 2.0 .99 Nov Sep May May May May 1988 1990 27 1987 12 1990 19 1990 17 1985 17 1985 30 1990 220 RIO GRANDB OB LOIZA BASIN 50051180 QUEBRADA 8ALVATIBRRA NEAR SAN LORBNZO, PR—Continued WATER-QUALITY RECORDS PERIOD OF RECORD.-- Water years 1984 to 1986 and water years 1989 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: October 1984 to September 1986 and from October 1989 to September 1992. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATION: Maximum daily 1 mg/L several days. in, 7,300 mg/L Oct. 06, 1985; Minimum daily SEDIMENT LOADS: Maximum daily mean, 11,100 tons (10,100 tonnes) Jan. 05, 1992; Minimum daily mean, 0.0 ton (0.0 tonne) several days. EXTREMES FOR WATER YEARS 1992.-- SEDIMENT CONCENTRATION: Maximum daily mean, 472 mg/L Jan. 05, 1992; Minimum daily 0.53 mg/L several days. in, SEDIMENT LOADS: Maximum daily mean, 11,100 tons (10,100 tonnes) Jan. 05 1992; Minimum daily mean, 0.0 ton (0.0 tonne) several days. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN DISCHARGE DAY (CFS) MEAN CONCEN- TRATION (MG/L) LOAD (TONS/ DAY) MEAN DISCHARGE (CFS) OCTOBER 1 2 3 4 S 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL 14 21 15 15 9.2 5.1 3.0 2.3 1.6 1.3 3.7 1.4 1.4 1.0 .90 .85 1.2 .79 .73 .60 .53 .53 2.4 .82 .65 .64 .61 .57 2.8 7.7 1.9 119.22 14 21 15 15 9 5 3 2 1 1 3 1 1 1 1 2 2 7 1 .2 .1 .0 .3 .6 .3 .7 .4 .4 .0 .90 .85 .2 .79 .73 .60 .53 .53 .4 .82 .65 .64 .61 .57 .8 .7 .9 ___ 2.3 6.3 3.0 3.9 1.1 .30 .09 .06 .02 .02 .42 .01 .01 .02 .02 .03 .02 .02 .02 .02 .02 .02 .27 .00 .00 .00 .00 .00 .50 3.2 21 42.69 1. 1. 1. 1. 9. 38 209 69 17 10 6. 3. 2. 1. 4. 3. 1. 1. 1. 2. 8. 2. 22 9. 4. 11 10 8. 5. - 470. MEAN CONCEN- TRATION (MG/L) LOAD (TONS/ DAY) MEAN MEAN CONCBN- DISCHARGB TRATION (CFS) (MG/L) NOVEMBER 6 8 95 2 5 4 7 7 3 8 1 1 5 1 1 9 2 6 1 7 9 8 -- 05 1. 1. 1. 1. 9. 38 209 69 17 10 6. 3. 2. 1. 4. 3. 1. 1. 1. 2. 8. 2. 22 9. 4. 11 10 8. 5. - _ 6 8 95 2 5 4 7 7 3 8 i 1 5 1 1 9 2 6 1 7 9 8 -- __ .19 .21 .09 .11 .15 2.8 35 1660 161 3.9 .30 .12 .05 .03 .02 .40 .19 .02 .02 .02 .34 1.0 .08 24 1.1 .17 2.0 1.7 .81 .20 --- 1896.02 3. 2. 7. 8. 4. 3. 2. 1. 1. 1. 1. 2. 2. 2. 1. 2. 2. 2. 2. 4. 5. 2. 1. 1. 1. 1. 1. 1. 1. 1. 2. 80. DECEMBER 7 4 2 1 9 1 1 9 7 5 3 1 0 4 8 2 2 1 2 4 2 1 8 4 4 4 4 3 3 3 9 8 3.7 2.4 7.2 8.1 4.9 3.1 2.1 1.9 1.7 1.5 1.3 2.1 2.0 2.4 1.8 2.2 2.2 2.1 2.2 4.4 5.2 2.1 1.8 1.4 1.4 1.4 1.4 1.3 1.3 1.3 2.9 ._- .08 .03 1.1 .61 .11 .05 .03 .02 .02 .02 .01 .02 .02 .01 .02 .01 .02 .02 .02 .30 .16 .02 .01 .00 .00 .00 .00 .00 .00 .01 .13 2.85 DAY RIO GRANDB DB LOIZA BASIN 50051180 QOBBRADA SALVATIBRRA NEAR SAN LORBNZO, PR—Continued DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 221 MEAN DISCHARGE (CFS) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN CONCEN- TRATION (MG/L) JANUARY LOAD (TONS/ DAY) 2.1 1.7 1.4 1.4 472 169 16 8.3 6.3 5.8 3.9 3.0 2.4 2.0 2.0 2.0 4.2 1.9 1.8 1.8 1.6 1.4 1.4 1.6 1.7 1.7 1.5 1.5 1.6 1.5 1.5 726.0 2.1 1.7 1.4 1.4 472 169 16 8.3 6.3 5.8 3.9 3.0 2.4 2.0 2.0 2.0 4.2 1.9 1.8 1.8 1.6 1.4 1.4 1.6 1.7 1.7 1.5 1.5 1.6 1.5 1.5 ___ .06 .02 .02 .02 11100 819 1.8 .18 .08 .08 .05 .02 .01 .02 .02 .03 .19 .03 .02 .02 .01 .00 .00 .00 .00 .00 .00 .01 .02 .02 .02 11921.75 MEAN DISCHARGE (CFS) MEAN CONCEN- TRATION (MG/L) FEBRUARY 1.4 1.4 1.4 1.7 1.3 2.3 3.2 1.6 1.4 4.4 2.1 1.5 1.4 1.2 1.4 1.3 1.2 1.2 1.2 1.3 1.3 1.3 1.4 1.7 1.6 1.5 1.4 1.4 1.3 1.4 1.4 1.4 1.7 1.3 2.3 3.2 1.6 1.4 4.4 2.1 1.5 1.4 1.2 1.4 1.3 1.2 1.2 1.2 1.3 1.3 1.3 1.4 1.7 1.6 1.5 1.4 1.4 1.3 46.8 LOAD (TONS/ DAY) .01 .00 .00 .01 .00 .00 .00 .00 .00 .26 .07 .01 .00 .00 .00 .01 .02 .01 .00 .01 .01 .02 .01 .02 .02 .02 .01 .00 .00 0.52 MEAN MEAN CONCBN- DISCHARGB TRATION (CFS) (MG/L) MARCH 1.2 1.1 1.1 1.2 1.3 1.4 1.4 1.3 1.1 1.0 1.0 1.0 1.0 1.1 1.5 1.2 1.3 1.5 1.2 1.5 1.1 1.1 1.1 .91 1.0 1.1 1.1 1.0 1.0 .94 .97 1.2 1.1 1.1 1.2 1.3 1.4 1.4 1.3 1.1 1.0 1.0 1.0 1.0 1.1 1.5 1.2 1.3 1.5 1.2 1.5 1.1 1.1 1.1 .91 1.0 1.1 1.1 1.0 1.0 .94 .97 35.72 LOAD (TONS/ DAY) .01 .02 .02 .02 .01 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .04 .02 .01 .00 .00 .00 .00 .00 .00 .01 .00 .01 0.17 2,22. RIO GRANDS DB LOIZA BASIN 50051180 QOEBRADA SALVATIBRRA NEAR SAN LORBNZO, PR--Continued DISCHARGE, CUBIC FBBT PBR SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAY MEAN DISCHARGE (CPS) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN CONCEN- TRATION (MG/L) APRIL 1.0 1.0 .94 1.1 1.1 .99 1.6 1.6 1.3 1.1 1.5 2.3 1.4 1.2 1.4 1.4 1.1 1.3 1.7 1.1 .84 .90 1.0 .94 1.0 1.1 1.1 1.1 .90 1.4 1.0 1.0 .94 1.1 1.1 .99 1.6 1.6 1.3 1.1 1.5 2.3 1.4 1.2 1.4 1.4 1.1 1.3 1.7 1.1 .84 .90 1.0 .94 1.0 1.1 1.1 1.1 .90 1.4 36.41 LOAD (TONS/ DAY) .00 .00 .00 .00 .00 .00 .00 .00 .00 ,01 ,00 ,02 ,02 ,01 ,03 .03 .02 .03 .04 .02 .01 .01 .01 .01 .01 .01 .00 .00 .00 .00 0.29 MEAN DISCHARGE (CPS) 40 8.0 4.4 2.5 2.2 1.6 244.0 MEAN CONCEN- TRATION (MG/L) MAY 40 8.0 4.4 2.5 2.2 1.6 LOAD (TONS/ DAY) 3.1 8.4 2.0 el.l el. 2 el. 8 e2.2 el. 6 el. 4 el. 3 el. 4 el. 5 el. 3 el. 2 el. 2 12 2.7 1.4 1.2 4.7 2.3 1.3 57 60 12 3.1 8.4 3 2.0 1.1 1.2 1.8 2.2 1.6 1.4 1.3 1.4 1.5 1.3 1.2 1.2 12 1' 2.7 1.4 1.2 4.7 2.3 1.3 57 S4C 60 7: 12 .39 L.6 .04 .02 .02 .02 .02 .01 .02 .02 .02 .02 .02 .02 .02 r .11 .00 .01 .60 .06 .02 ) 1 1.0 190 .22 .08 .04 .04 .03 826.47 MEAN DISCHARGE (CPS) MEAN CONCEN- TRATION (MG/L) JUNE LOAD (TONS/ DAY) 3.3 3.2 1.6 45 6.8 3.S 3.0 3.3 3.0 4.9 4.S 41 16 11 6.S 6.4 4.7 3.2 2.3 2.3 10 3.S 2.3 2.0 1.8 1.4 1.6 1.6 1.3 1.2 3.3 3.2 1.6 45 6.8 3.S 3.0 3.3 3.0 4.9 4.S 41 16 11 ' 6.S 6.4 4.7 3.2 2.3 2.3 10 3.S 2.3 2.0 1.8 1.4 1.6 1.6 1.3 1.2 .25 .35 .06 250 .41 .14 .10 .07 .05 .32 .15 130 3.6 1.4 .19 .41 .14 .06 .03 .05 1.9 .16 .10 .08 .05 .04 .03 .02 .02 .02 202.2 390.20 e Estimated RIO GRANDB DB LOIZA BASIN 50051180 QUBBRADA SALVATIBRRA NEAR SAN LORBNZO, PR--Continued DISCHARGE, CUBIC PBBT PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 223 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL YEAR MEAN DISCHARGE (CPS) 1.2 1.1 1.0 2.4 3.6 1.2 1.0 1.1 1.3 1.0 1.5 1.3 1.1 .99 .93 2.0 6.9 1.8 1.7 2.0 1.8 6.7 2.4 1.7 1.7 1.4 1.4 1.4 1.3 1.2 1.2 57.32 2550.22 MEAN CONCEN- TRATION (MG/L) JULY 1.2 1.1 1.0 2.4 3.6 1.2 1.0 1.1 1.3 1.0 1.5 1.3 1.1 .99 .93 2.0 6.9 1.8 1.7 2.0 1.8 6.7 2.4 1.7 1.7 1.4 1.4 1.4 1.3 1.2 1.2 —— LOAD (TONS/ DAY) .02 .01 .02 .18 .33 .07 .03 .02 .02 .02 .01 .02 .02 .02 .02 .02 2.1 .36 .28 .29 .25 1.9 .23 .05 .04 .04 .03 .02 .02 .02 .02 6.48 16650.19 MEAN DISCHARGE (CPS) 1.2 1.3 1.2 1.2 64 13 7.5 5.2 3.4 9.0 4.9 6.2 4.7 3.6 3.2 2.5 2.1 2.1 1.8 1.7 1.6 1.5 1.4 e2.5 e2.0 e2.2 e2.0 el. 9 el. 8 el. 7 e3.5 161.9 MEAN CONCEN- TRATION (MG/L) AUGUST 1.2 1.3 1.2 1.2 64 13 7.5 5.2 3.4 9.0 4.9 6.2 4.7 3.6 3.2 2.5 2.1 2.1 1.8 1.7 1.6 1.5 1.4 2.5 2.0 2.2 2.0 1.9 1.8 1.7 3.5 —— LOAD (TONS/ DAY) MEAN DISCHARGE (CPS) MEAN CONCEN- TRATION (MG/L) LOAD (TONS/ DAY) SEPTEMBER .02 .02 .02 .02 269 26 1.6 .65 .19 .69 .27 .21 .09 .04 .04 .04 .03 .04 .02 .02 .02 .03 .05 e.ll e.06 e.03 e.02 e.02 e.02 e.03 e.07 299.47 el. 9 el. 6 3.7 e2.5 el. 6 e3.5 e2.5 el. 8 e4.0 2.2 1.7 1.6 1.5 1.5 1.7 2.8 6.3 6.7 54 119 56 20 13 10 9.1 8.9 8.6 7.9 7.2 7.0 369.8 1.9 1.6 3.7 2.5 1.6 3.5 2.5 1.8 4.0 2.2 1.7 1.6 1.5 1.5 1.7 2.8 6.3 6.7 54 119 56 20 13 10 9.1 8.9 8.6 7.9 7.2 7.0 —— e.04 e.04 .09 e.06 e.04 e.06 e.04 e.09 e.22 .04 .02 .01 .02 .02 .00 .19 .45 .61 226 980 52 1.9 .65 .19 .09 .11 .12 .07 .06 .05 1263.28 e Estimated 224 RIO GRANDB DB LOIZA BASIN 50051180 QOBBRADA SALVATIERRA NEAR SAN LORBNZO, PR--Continued HATER QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 PARTICLE-SIZE DISTRIBUTION OP SUSPENDED SEDIMENT DATE NOV 1991 08. . . MAY 1992 23. .. JUN 04. .. 12. .. DATE NOV 1991 08. .. MAY 1992 23.. . JUN 04. .. 12. .. TIME 1615 2027 0941 0426 SBD. SUSP. PALL DIAM. PERCENT FINER THAN .016 MM 72 48 52 52 DIS- CHARGE, INST. CUBIC PBBT PER SECOND 248 375 417 115 SED. SUSP. PALL DIAM. PERCENT FINER THAN .031 MM 80 60 62 63 SEDI- MENT, SUS- PENDED (MG/L) 2120 30400 5500 4040 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 98 82 78 88 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 1420 30800 6190 1250 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 99 94 82 97 SED. SUSP. PALL DIAM. PERCENT FINER THAN .002 MM 41 24 27 32 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 99.7 99 87 99 SBD. SUSP. PALL DIAM. PERCENT FINER THAN .004 MM 49 30 34 37 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 99.8 99.7 91 99.8 SBD. SUSP. PALL DIAM. PERCENT FINER THAN .008 MM 55 34 41 42 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 100 100 96 100 RIO GRANDB DB LOI2A BASIN 50051180 QOBBRADA SALVATIBRRA NEAR SAN LORBNZO--Continued WATER QUALITY DATA, WATER YBAR OCTOBER 1991 TO SEPTEMBER 1992 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT 225 DATE NOV 1991 06... JAN 1992 06... MAY 23... 24.. . OUN 04.. . 04.. . 04.. . 12.. . SEP 18.. . TIME 1011 132S 2012 0047 0921 10S5 1221 0421 102S STREAM- FLOW, INSTAN- TANEOUS (CFS) 0.83 86 261 2SS 117 210 95 108 11 SEDI- MENT, SUS- PENDED (MQ/L) 38 134 2290 1130 3840 1780 4S9 11000 603 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 0.1 31 1610 781 1210 1010 117 3200 18 880. SUSP. SIEVE DIAM. PERCENT FINER THAN 062 MM 83 97 91 65 SS 96 98 90 97 226 RIO ORANDB OB LOIZA BASIN 50051310 RIO CAYAOOAS AT CBRRO GORDO, PR LOCATION.—L»t 18«09'13", long 650 57'20", Hydrologic Unit 21010005, at downstream aide of bridge on Highway 912, at Barrio Cerro Qordo, 2.8 mi (4.5 km) south of San Lorenzo. DRAINAGE ARBA.--10.2 mi 1 (26.4 km1 )- HATER-DISCHARGE RECORDS PERIOD OF RECORD.—October 1977 to current year. QAGB.--Hater-stage recorder and crest-stage gage. Elevation of gage is 490 ft (150 m), from topographic map. Prior to Oct. 1, 1983, at site 2,000 ft (610 m) downstream at different datum. REMARKS.--Records poor. Sand removal at a commercial level is practiced at times during the year. This takes place about one hundred feet downstream from the low water control. Gage-height and precipitation satellite telemetry at station. DAY DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES OCT NOV DEC JAN PBB MAR APR MAY JUN JUL ADO SEP 1 21 11 2 35 12 3 19 12 4 16 14 5 17 16 6 16 13 7 14 60 8 14 970 9 15 120 10 14 43 11 13 21 12 15 19 13 15 17 14 14 16 15 14 15 16 13 15 17 16 14 18 14 14 19 13 13 20 12 13 21 12 15 22 12 38 23 12 18 24 12 49 25 11 22 26 11 16 27 11 23 28 11 20 29 11 19 30 11 16 31 11 - — TOTAL 445 1664 MEAN 14.4 55.5 MAX 35 970 MIN 11 11 AC-FT 883 3300 CFSM 1.41 5.44 IN. 1.62 6.07 e Estimated STATISTICS OF MONTHLY MEAN MEAN 66.0 75.2 MAX 176 196 (WY) 1986 1988 MIN 14.4 19.2 (WY) 1992 1982 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 15 16 16 17 15 14 13 13 13 13 12 13 12 12 12 14 12 12 12 13 13 11 11 11 10 10 10 10 10 11 12 388 12.5 17 10 770 1.23 1.42 DATA 46.9 163 1988 12.5 1992 FOR 11 10 9.5 9.3 777 264 26 14 11 11 10 9.8 9.8 9.3 9.7 10 9.4 9.5 9.4 9.5 9.3 9.5 9.6 9.8 9.8 9.9 9.5 9.9 10 9.8 9.9 1346.2 43.4 777 9.3 2670 4.26 4.91 FOR WATER 28.7 46.4 1988 14.6 1990 9.9 10 10 11 10 14 12 10 11 12 11 10 10 11 12 11 10 10 11 11 11 11 11 12 11 12 12 12 11 --- 319.9 11.0 14 9.9 635 1.08 1.17 YEARS 1977 26.7 67.5 1984 11.0 1992 11 11 11 12 11 12 16 16 11 10 10 10 10 11 11 10 14 14 11 11 12 11 11 11 11 11 11 10 10 9.9 9.9 350.8 11.3 16 9.9 696 1.11 1.28 - 1992 21.9 45.4 1989 11.3 1992 1991 CALENDAR YEAR 7044. 19. 970 9. 9. 13970 1. 25. 22 14 10 7 3 Nov 8 0 May 31 4 Jun 14 89 69 11 12 10 9.6 9.2 9.0 9.4 9.0 8.7 8.5 9.4 15 13 11 12 11 11 11 22 33 15 13 11 11 11 10 10 10 10 11--- 356.8 11.9 33 8.5 708 1.17 1.30 14 30 13 11 10 30 22 13 11 10 10 10 9.5 9.9 12 170 30 21 18 20 17 16 330 165 72 831 54 33 28 27 25 2072.4 66.9 831 9.5 4110 6.55 7.56 109 73 41 195 112 89 80 81 79 105 83 e!77 118 110 79 82 110 94 78 85 184 41 38 27 27 26 29 27 26 26 2431 81.0 195 26 4820 7.94 8.87 25 25 25 32 46 31 32 46 47 43 83 51 42 41 53 42 96 72 84 99 68 186 54 44 88 52 46 40 38 36 36 1703 54.9 186 25 3380 5.39 6.21 40 38 39 42 284 98 39 37 54 108 52 60 40 56 53 41 42 32 28 30 25 25 27 35 28 32 39 40 44 39 51 1598 51.5 284 25 3170 5.05 5.83 43 40 52 35 31 45 43 38 159 37 26 25 26 26 28 56 39 42 131 694 240 44 32 25 20 16 15 15 16 17 --- 2056 68.5 694 15 4080 6.72 7.50 , BY WATER YEAR (WY) 20.9 46.0 1985 10.7 1980 FOR 1992 14731 40 970 8 9 7300 19 29220 3 53 80 15 10 50.3 155 1985 9.68 1990 WATER YEAR .1 .2 Nov 8 .5 Apr 10 . 0 Apr 5 May 26 .12 May 26 .95 .73 47.9 140 1979 14.4 1991 42.2 118 1979 16.0 1990 WATER 44 89 18 2900 7 8 13200 9 7 32030 4 58 67 24 12 47.6 202 1979 14.5 1991 YEARS 1977 - .2 .7 .6 Aug 31 . 1 Feb 4 . 6 Apr 7 Aug 31 .44 Aug 31 . 1 Feb 4 .33 .90 55.4 216 1979 16.9 1980 1992 1979 1990 1979 1981 1983 1979 1979 1981 RIO GRANOB DB LOIZA BASIN 50051800 RIO GRANOB DB LOIZA AT HWY 183 NEAR SAN LORENZO, PR 227 LOCATION.--Lat 18°11'09-, long 650S7'42", Hydrologic Unit 21010005, at upstream side of bridge on Highway 183 by-pass, 0.4 mi (0.6 km) south from Plaza de San Lorenzo, 1.4 mi (2.2 km), southwest from Bscuela Rafael Col6n Oarcia and 2.0 mi (3.2 km) northwest from Bscuela Segunda Unidad de Carlos Zayas. DRAINAQB AREA.--25.0 mi» (64.8km>). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--February 1990 to current year. GAQB.—Water-stage recorder. Elevation of gage is 262 ft (80 m), from topographic map. REMARKS.--Records poor. Water purification plant located about 0.2 mi (0.3 km) upstream from gage. Gage-height and precipitation satellite telemetry at station. DAY DISCHARGE, CUBIC FEET PBR SECOND, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES OCT NOV DBC JAN FBB MAR APR MAY JUN JUL AUG SBP 1 159 e66 2 221 e46 3 162 eS4 4 121 e49 5 118 e43 6 102 e66 7 79 e76 8 73 e2600 9 76 402 10 72 248 11 68 173 12 99 150 13 78 127 14 66 115 15 68 103 16 63 116 17 79 103 18 63 88 19 54 82 20 43 79 21 43 94 22 40 240 23 e66 142 24 eSO 299 25 e44 196 26 e40 135 27 e35 228 28 e34 220 29 e33 192 30 e!20 143 31 elSO --- TOTAL 2519 6675 MEAN 81.3 222 MAX 221 2600 MIN 33 43 AC-FT 5000 13240 CFSM 3.25 8.90 IN. 3.75 9.93 e Estimated STATISTICS OF MONTHLY MEAN MEAN 174 168 MAX 266 222 (WY) 1991 1992 MIN 81.3 113 (WY) 1992 1991 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 124 127 127 151 114 102 e94 e88 e90 e84 e76 eSO e76 e70 e72 e76 e74 e62 e60 e74 e!30 e68 e67 61 59 54 55 54 55 58 79 2561 82.6 151 54 5080 3.30 3.81 DATA 84.7 86.7 1991 82.6 1992 FOR 71 55 51 48 3380 1080 168 117 83 85 66 57 53 47 48 46 48 40 38 37 35 34 31 33 32 34 29 30 28 26 25 5955 192 3380 25 11810 7.68 8.86 24 22 22 26 22 41 38 26 23 33 25 20 18 21 25 21 17 16 16 14 14 16 16 17 16 16 16 15 14 ___ --- 610 21.0 41 14 1210 .84 .91 FOR WATER YEARS 1990 127 192 1992 62.9 1991 46.6 71.1 1991 21.0 1992 12 11 e!3 e20 e30 e20 e22 e!8 e!7 elS e!4 e!4 elS e20 e!4 e23 e21 e28 e!8 e20 e21 e!7 e!6 e!4 e!8 e!7 e!6 e!4 e!3 e!3 e!4 538 17.4 30 11 1070 .69 .80 - 1992 34.7 48.7 1991 17.4 1992 1991 CALENDAR YEAR 27414 75 2600 17 21 54380 3 40 130 49 25 .1 Nov 8 Jun 26 Jun 22 .00 .79 e!9 e!6 e!4 13 11 10 14 12 10 10 13 47 35 30 26 14 12 11 22 65 23 14 11 9.2 8.3 7.9 7.1 6.8 6.3 6.5 --- 504.1 16.8 65 6.3 1000 .67 .75 9.1 50 12 7.8 6.9 43 36 16 12 11 12 12 8.4 8.7 28 e600 e!20 e60 e45 e80 e56 e38 e800 e!200 e!80 e!600 e270 e!20 e85 e!40 e84 5750.9 186 1600 6.9 11410 7.42 8.56 e300 e270 elOO eS40 elSO e!40 e250 e490 e520 e470 e660 eSOO e460 e400 e360 377 385 289 179 173 466 210 179 150 133 124 122 115 102 97 --- 8711 290 660 97 17280 11.6 12.96 92 80 78 99 127 81 76 92 95 83 134 98 80 79 90 86 179 111 132 159 123 270 134 116 192 127 116 105 98 96 96 3524 114 270 76 6990 4.55 5.24 100 100 109 104 592 273 192 157 160 241 161 168 130 157 142 116 103 92 85 85 79 76 74 85 73 70 79 70 78 65 84 4100 132 592 65 8130 5.29 6.10 75 64 103 71 61 76 73 59 177 72 60 54 49 47 48 e75 e420 ellO e800 e2500 e!400 e230 180 153 137 126 117 106 103 100 —— 7646 255 2500 47 15170 10.2 11.38 , BY WATER YEAR (WY) 25.5 31.8 1991 16.8 1992 FOR 1992 49094 134 3380 6 7 28200 27 97380 5 73 233 72 14 85.9 186 1992 35.1 1991 WATER YEAR .0 Jan 5 .3 Apr 29 .4 Apr 25 Jan 5 .36 Jan 5 .37 .05 140 290 1992 47.8 1991 86.8 114 1992 66.0 1990 WATER 108 134 82 3380 6 7 28200 27 78390 4 58 164 50 19 96.0 132 1992 48.6 1991 YEARS 1990 .2 Jan .3 Apr .4 Apr Jan .36 Jan .33 .81 135 255 1992 59.7 1990 - 1992 1992 1991 5 1992 29 1992 25 1992 5 1992 5 1992 228 RJO GRANDS OS LOIZA BASIN 50051800 RIO GRANDS DS LOIZA AT HWY 183 NEAR SAN LORBNZO, PR--Continued HATBR-QUALITY RECORDS PERIOD OF RECORDS.-- Hater year* 1990 to current year. INSTROMBNTATION.-- DH-48 and automatic sediment sampler. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGEi February 1990 to September 1992 EXTREMES FOR PERIOD OP DAILY RECORD.— SEDIMENT CONCENTRATION> Maximum daily 5 mo/L Several day*. san, 1,570 mg/L Jun. 11, 1992; Minimum daily mean. SEDIMENT LOADSi M^xip«"m daily mean, 46,800 tone (42,400 tonne*) Jan. 05, 1992; Minil 0.20 ton (0.18 tonne) May 05, 1992. daily mean, EXTREMES FOR WATER YEARS 1990-92.-- Water Year 1990 1991 1992 Suspended-sediment concentration (mg/L) maximum minimum 569 (Jun. 15) 950 (Oct. 21) 1,570 (Jun. 11) 41 (Apr. 30) 5 (Jun. 04-05) 5 (Several days) Suspended-sediment discharge (tone per day) 1,950 (Aug. 28) 5,740 (Oct. 21) 46,800 (Jan. 05) 2 (May, 21) .33 (Jun. 04) .20 (may, 05) SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1989 TO SEPTEMBER 1990 DAY MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) JANUARY MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) FEBRUARY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL e46 e38 e35 e30 e29 e40 e50 e65 e50 46 36 32 33 41 37 32 35 41 35 39 60 64 57 204 60 48 41 36 1360 97 93 79 73 87 94 93 75 74 83 81 96 118 125 124 267 121 96 90 85 el3 12 7.8 6.5 7.3 10 9.6 6.8 6.7 8.8 7.7 11 21 24 18 188 20 12 10 8.5 MEAN DISCHARGE (CFS) 40 37 33 32 30 28 27 26 29 35 34 46 50 130 64 56 56 40 34 33 30 27 31 29 28 26 27 29 32 30 29 1178 MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) MARCH 87 81 80 79 73 69 64 64 64 72 83 93 102 206 138 120 121 91 77 80 75 66 74 75 64 61 64 71 72 70 67 9.8 8.2 7.1 7.1 5.8 5.2 4.8 4.5 5.0 6.9 7.9 11 14 82 25 18 19 10 7.2 7.2 6.3 4.7 5.9 5.8 4.8 4.4 4.9 5.4 6.3 5.4 5.3 324.9 e Estimated RIO GRANDB DB LOIZA BASIN 500S1800 RIO GRANDB DB LOIZA AT HWY 183 NEAR SAN LORENZO, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1989 TO SEPTEMBER 1990 229 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCBN- SEDIMENT MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DAY (CPS) (MG/L) (TONS/DAY) (CPS) (MG/L) (TONS/DAY) (CPS) (MG/L) (TONS/DAY) 1 2 3 4 S 6 7 8 9 10 11 12 13 14 IS 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 27 26 27 26 27 25 23 22 22 21 20 21 42 37 24 23 24 23 26 26 21 19 19 19 53 76 49 27 22 19 _._ APRIL 63 61 62 65 62 59 57 57 57 50 52 55 84 80 58 85 60 60 162 192 174 152 121 61 97 183 84 66 54 41 __. MAY 4 3 3 3 2 2 3 10 8 3 5 3 3 11 14 10 7 5 3 22 40 11 5 3 2 - .7 .4 .5 .5 .5 .1 .4 .3 .2 .8 .6 .2 .6 .9 .2 .7 .6 .5 .8 .1 .0 .3 .1 -- 19 20 19 19 19 18 18 22 154 247 118 44 34 36 30 27 25 24 21 20 17 19 19 18 15 30 25 20 19 15 17 49 50 79 69 89 87 83 64 141 303 184 93 78 60 75 66 65 61 54 49 41 55 62 55 56 69 65 53 55 46 43 2 2 3 4 4 4 3 3 412 301 66 12 7 5 6 4 4 3 3 2 2 2 3 2 2 5 4 2 2 2 2 .6 .7 .8 .6 .7 .3 .7 .9 .2 .6 .2 .7 .3 .9 .2 .6 .0 .9 .4 .7 .4 .9 .7 .8 .8 .0 .0 JUNE 18 19 IB 19 41 53 39 24 38 26 21 19 19 515 399 136 77 54 46 76 50 41 38 52 263 123 72 52 44 40 -_- 47 46 47 63 160 121 67 60 60 67 72 50 53 375 569 209 125 49 46 128 69 61 57 54 321 151 52 85 61 66 --- 2.2 2.4 2.3 3.3 16 19 7.0 4.0 9.6 4.7 3.8 2.5 2.5 1620 754 83 28 7.1 5.6 29 9.4 6.9 5.9 7.6 275 50 11 12 7.1 9.4 --- TOTAL 836 215.0 1148 892.8 2434 3002.7 230 RIO GRANDB DB LOIZA BASIN 50051800 RIO GRANDB DB LOIZA AT HWY 183 NEAR SAN LORBNZO, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1989 TO SEPTEMBER 1990 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/ DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 57 49 38 42 41 138 77 58 42 41 39 36 37 52 55 54 49 70 135 62 44 36 31 48 224 222 89 55 46 41 37 JULY 104 63 55 53 53 198 143 113 64 43 46 46 53 105 107 100 101 133 210 108 78 78 51 66 291 287 165 108 96 86 82 17 8.6 5.5 5.7 6.0 99 30 18 7.3 4.8 4.8 4.3 6.4 17 18 17 15 28 81 20 9.4 7.5 4.2 13 205 233 43 16 13 9.5 8.4 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) AUGUST 36 40 40 46 56 44 54 210 81 800 193 102 115 82 67 61 54 51 51 46 43 46 49 53 47 50 38 526 134 60 45 79 87 64 61 92 111 126 285 148 619 268 157 190 151 106 74 62 47 35 25 24 24 80 26 26 26 27 320 204 116 92 7. 10 6. 7. 14 13 22 197 34 2570 160 41 64 36 19 12 8. 6. 4. 3. 2. 2. 9. 3. 3. 3. 2. 1950 97 20 11 8 9 6 9 3 7 0 8 9 6 6 4 4 6 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) SEPTEMBER 40 39 39 55 35 31 29 33 32 34 28 30 52 84 79 111 76 85 78 45 39 36 99 58 44 103 70 143 94 70 85 83 85 95 101 97 90 83 78 72 66 71 102 147 143 183 129 150 135 92 84 80 151 113 94 154 129 197 162 137 9.1 8.7 9.1 15 9.5 8.0 7.2 7.6 6.9 6.4 5.1 5.7 15 43 33 67 28 47 30 11 9.0 8.0 80 19 12 63 27 186 48 29 TOTAL 2045 975.4 3320 5343.5 1791 853.3 RIO GRANDS DB LOIZA BASIN 50051800 RIO GRANDS DB LOIZA AT HWY 183 NEAR SAN LORBNZO, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 231 MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) OCTOBER MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) NOVEMBER MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) DECEMBER 65 51 57 50 46 41 37 45 135 133 88 60 142 117 97 353 144 301 724 410 1390 243 170 484 810 800 398 269 213 192 188 120 92 77 62 65 70 77 94 189 204 159 125 223 187 223 382 144 243 351 391 950 123 195 421 638 663 430 340 285 285 271 23 13 11 8. 8. 8. 7. 13 146 75 40 21 91 75 59 734 66 451 877 1820 5740 104 90 1530 1960 1650 506 267 162 152 140 8 0 1 9 163 152 138 359 320 199 152 130 113 105 96 89 84 79 76 76 74 71 70 69 66 70 64 60 60 74 90 83 64 159 236 225 177 373 309 277 182 103 73 58 45 30 15 9 9 9 10 10 10 10 11 14 17 20 20 75 151 151 145 235 100 89 66 571 340 157 78 39 22 16 11 7.0 3.2 1.9 1.8 1.8 1.9 1.9 1.8 1.8 1.9 2.5 2.9 3.1 3.2 20 35 35 26 115 102 84 122 95 70 61 56 54 53 51 55 49 42 229 120 86 70 61 56 56 52 53 51 52 48 45 47 54 70 78 566 199 154 225 179 131 118 111 106 104 54 49 51 65 295 180 154 132 117 109 109 106 98 85 68 45 15 9 11 63 158 508 59 37 82 50 24 19 17 15 15 7.5 7.5 7.0 7.5 214 61 36 25 19 16 16 15 13 11 9.2 5.8 1.8 1.2 1.7 15 34 1120 TOTAL 8253 16848.8 3405 1756.7 2688 1962.2 232 RIO GRANDB OB LOIZA BASIN 50051800 RIO GRANDB OB LOIZA AT HWY 183 NEAR SAN LORENZO, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN DISCHARGE (CPS) 124 77 65 59 82 80 86 90 89 79 69 70 66 67 80 65 55 50 49 47 46 44 46 44 48 46 46 46 45 43 47 MEAN CONCEN- TRATION (MG/L) JANUARY 117 29 21 21 79 154 136 161 175 134 126 131 131 56 48 48 48 46 45 43 42 42 42 42 42 48 57 67 92 88 104 SEDIMENT DISCHARGE (TONS/ DAY) 42 6.8 3.6 3.3 29 38 32 42 44 27 23 25 25 9.6 10 8.6 7.4 6.4 5.8 5.3 5.1 5.1 5.3 5.2 5.2 6.1 7.1 8.1 11 10 13 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) FEBRUARY MEAN DISCHARGE (CPS) MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) 54 46 56 50 121 129 81 45 40 42 111 133 155 68 60 51 46 45 80 74 94 69 58 59 59 58 49 59 106 92 103 102 164 196 134 94 84 89 180 189 252 197 204 201 198 193 159 158 145 118 109 110 117 111 98 216 16 11 IS 14 115 79 31 12 9.1 11 65 118 122 38 33 29 24 24 35 37 38 23 17 17 19 18 13 38 MARCH 58 50 53 67 63 106 89 93 67 54 49 50 45 47 45 40 37 38 47 36 34 46 46 35 32 31 31 30 e34 e29 e29 340 306 274 240 235 235 235 230 228 228 227 227 226 225 229 241 250 260 268 303 333 345 363 375 390 408 432 433 425 418 415 1950 475.0 1992 1021.1 1511 54 41 38 43 41 65 55 57 42 33 30 30 28 29 29 27 25 26 32 29 31 44 45 36 35 33 35 35 e37 e36 e33 1154 e Estimated RIO GRANDS DB LOIZA BASIN 233 JAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CPS) e29 e30 630 628 628 e28 e27 635 639 657 638 644 634 629 e55 646 634 637 632 626 626 628 626 624 627 626 625 623 622 621 ___ 50051800 RIO GRANDS DB LOIZA AT HWY 183 NEAR SAN LORBNZO, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) APRIL 400 375 378 378 378 378 378 378 378 378 378 378 378 378 378 390 400 400 410 415 415 425 416 400 400 380 375 370 358 358 e31 e30 c31 e29 e29 e29 c28 e36 c40 c58 658 e45 e35 c30 e56 C48 e37 640 e35 e29 e29 c32 e29 c26 e29 e27 e25 e23 621 620 MEAN MEAN MEAN CONCBN- SEDIMENT MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) (CFS) (MG/L) (TONS/DAY) MAY e22 e21 e22 630 e26 625 627 625 624 622 623 655 e28 623 624 e26 623 639 629 e30 e54 57 31 23 197 62 32 26 22 21 20 358 358 358 358 358 58 61 58 56 52 54 107 63 54 56 690 760 830 920 67 105 99 83 68 244 128 72 61 58 24 7 621 620 e21 629 625 63 64 63 63 63 63 e!6 64 63 63 648 e47 687 672 65 e!5 15 7 4 233 25 6 4 3 1 .9 .4 .9 .6 .1 .4 .8 .4 .6 .4 .0 .5 .5 .4 .4 .4 .37 JUNE 25 30 22 23 28 52 42 33 29 26 32 82 38 27 31 23 20 20 19 19 26 25 21 22 21 17 19 24 30 609 6 6 6 5 5 96 82 322 64 68 93 135 93 68 67 55 50 49 50 50 61 66 57 42 59 51 52 57 68 383 __- .41 .48 .35 .33 .37 14 9.5 26 4.9 4.8 8.0 37 9.9 5.0 5.9 3.5 2.8 2.7 2.5 2.5 4.6 4.7 3.4 2.5 3.4 2.4 2.7 3.8 6.7 1540 -.- TOTAL 954 1015 1089 741.07 1435 1715.14 e Estimated 234 RIO GRANDB DB LOIZA BASIN 50051800 RIO GRANDB DB LOIZA AT HWY 183 NEAR SAN LORBNZO, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) (CFS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL YEAR 597 143 83 71 53 47 40 34 33 33 27 25 25 24 75 371 117 69 56 65 50 42 44 56 48 38 42 40 39 64 51 2502 30005 JULY 552 230 161 131 106 91 82 76 72 79 75 60 59 57 115 362 181 136 139 126 97 89 96 113 104 85 85 85 89 143 115 —— AUGUST 1410 95 36 24 16 11 8.6 7.2 6.4 7.1 5.8 4.1 4.1 3.8 57 442 62 26 22 23 13 10 11 18 14 8.8 9.4 9.4 9.0 26 16 2415.7 31737.31 38 36 33 29 28 30 29 25 24 22 23 20 22 26 32 26 49 62 40 29 61 145 95 49 38 35 118 170 71 56 46 1507 85 77 73 67 65 69 56 61 61 57 55 54 58 71 69 59 89 101 82 74 84 208 173 96 80 74 171 267 136 104 91 —— 8.7 7.4 6.6 5.5 5.1 5.8 4.3 3.9 3.8 3.3 3.5 2.9 3.4 5.3 6.1 4.2 12 17 8.8 5.8 14 112 54 13 8.1 6.8 97 138 28 15 11 620.3 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) SEPTEMBER 43 60 35 31 29 33 28 31 67 55 49 37 34 34 33 31 330 132 80 61 79 187 217 130 85 69 88 165 268 198 ___ 2719 100 98 78 71 70 78 85 78 119 109 90 81 77 76 73 74 414 46 28 23 94 265 277 206 153 136 157 249 361 271 ___ —— 12 16 7.6 5.8 5.5 7.0 6.7 6.7 28 18 12 7.9 7.0 6.8 6.5 6.0 758 19 5.9 3.9 25 157 159 77 34 26 41 123 277 147___ 2012.3 RIO GRANDE DE LOIZA BASIN 235 50051800 RIO GRANDE DE LOIZA AT HWY 183 NEAR SAN LORENZO. PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) NOVEMBER MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CPS) (MG/L) (TONS/DAY) OCTOBER 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 159 221 162 121 118 102 79 73 76 72 68 99 78 66 68 63 79 63 54 43 43 40 e66 e50 e44 e40 e35 e34 e33 e!20 e!50 230 367 229 156 176 142 101 89 97 95 85 162 95 88 88 88 89 95 108 119 121 110 81 60 53 48 42 41 40 163 213 102 245 103 49 63 42 22 17 20 20 16 54 20 17 16 15 19 16 16 14 14 12 e!4 e8 e6. e5 e4, e3 e3, e53 e86 .1 .3 .2 .0 .8 .6 e66 e46 e54 e49 e43 e66 e76 >2600 402 248 173 150 127 115 103 116 103 88 82 79 94 240 142 299 196 135 228 220 192 143 81 55 65 59 52 81 94 1000 851 410 265 166 95 75 70 130 145 111 103 99 127 385 87 553 220 60 369 363 314 173 e!4 e6. e9. e7. e6. e!4 e!9 e!8200 1260 284 131 68 35 23 19 51 44 26 23 21 46 286 35 567 128 23 250 230 179 69 8 5 8 0 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) DECEMBER 124 127 127 151 114 102 e94 e88 e90 e84 e?6 e80 e76 e70 e72 e76 e74 e62 e60 e74 e!30 e68 e67 61 59 54 55 54 55 58 79 100 69 57 48 38 41 48 48 43 39 38 38 38 38 25 15 9 6 5 5 7 10 10 10 7 5 7 10 8 7 14 33 22 20 19 12 11 e!2 ell elO e8. e7. e8. e7. e7. e4. e3. el. . el. e. el. e2. el. el. 1. 1. 1. 1. 1. 1. 3. 9 8 2 8 2 9 1 8 1 82 0 6 8 8 7 2 77 1 5 2 1 0 TOTAL 2519 1096.0 6675 22075.1 2561 220.39 e Estimated 236 RIO GRANDB DB LOIZA BASIN 50051800 RIO GRANDB DB LOIZA AT HWY 183 NEAR SAN LORKNZO, PR--Continued SBDIMKNT DISCHARGE, SDSPBNDBD (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) JANUARY 71 55 51 48 3380 1080 168 117 83 85 66 57 53 47 48 46 48 40 38 37 35 34 31 33 32 34 29 30 28 26 25 15 15 18 20 1380 507 190 63 56 68 65 55 45 34 31 46 59 53 38 28 28 30 29 25 21 20 20 20 21 26 35 3 2 2 2 46800 1950 92 21 13 14 12 8 6 4 4 5 7 S 3 2 2 2 2 2 1 1 1 1 1 1 2 .2 .3 .4 .6 .7 .4 .3 .1 .6 .6 .6 .8 .7 .6 .6 .5 .2 .9 .7 .6 .6 .7 .8 .3 MEAN DISCHARGE (CFS) MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) 24 22 22 26 22 41 38 26 23 33 25 20 18 21 25 21 17 16 16 14 14 16 16 17 16 16 16 15 14 45 55 61 61 59 58 59 81 94 113 74 48 27 19 20 19 17 14 14 19 22 21 20 19 18 16 15 16 17 2 3 3 3 3 6 6 5 5 10 5 2 1 1 1 1 .8 .3 .6 .9 .7 .2 .2 .3 .9 .3 .7 .3 .1 .3 .1 .75 .60 .61 .77 .84 .84 .91 .92 .82 .66 .63 .60 .60 5955 48983.8 610 73.25 MEAN DISCHARGE (CFS) 12 11 e!3 «20 •30 •20 •22 •18 •17 •15 •14 •14 e!5 •20 •14 e23 021 •28 • 18 020 •21 • 17 • 16 • 14 • 18 • 17 016 • 14 • 13 • 13 • 14 538 MEAN CONCEN- TRATION (MG/L) MARCH 18 18 20 20 20 20 20 21 21 20 20 20 20 20 20 20 20 20 20 19 17 16 16 16 18 22 27 34 41 46 251 ___ SEDIMENT DISCHARGE (TONS/DAY) .57 .55 • .66 • 1.1 • 1.6 • 1.1 • 1.2 • 1.0 .94 .82 .76 .76 .82 • 1.1 • .76 • 1.2 • 1.1 • 1.5 • .98 • 1.0 • .96 • .74 • .70 • .60 • .88 • .99 • 1.2 • 1.3 • 1.4 • 1.6 • 9.5 39.39 0 Estimated RIO GRANDS DE LOI£A BASIN 50051800 RIO GRANGE DB LOIZA AT HWY 183 NEAR SAN LORBNZO, PR--Continued SBDIMKNT DISCHARGE, SOSPBNDKD (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CPS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 • 19 • 16 • 14 13 11 10 14 12 10 10 13 47 35 30 26 14 12 11 22 65 23 14 11 9.2 8.3 7.9 7.1 6.8 6.3 6.S --- APRIL 41 32 25 22 24 24 20 18 19 22 21 55 47 38 32 19 13 10 28 80 23 20 18 17 18 21 25 31 29 20 ___ MEAN DISCHARGE (CPS) MEAN CONCEN- TRATION (MG/L) SEDIMENT DISCHARGE (TONS /DAY) MAY • 2.1 • 1.4 • .93 .78 .70 .70 .70 .63 .53 .57 .£9 10 5.8 4.3 2.7 .76 .41 .30 2.4 21 1.6 .76 .59 .47 .39 .46 .49 .57 .49 .36 ___ 9.1 50 12 7.8 6.9 43 36 16 12 11 12 12 8.4 8.7 28 •600 •120 • 60 •45 • 80 •56 • 38 •800 • 1200 •180 • 1600 •270 •120 • 85 •140 • 84 16 65 15 10 10 54 50 18 16 13 12 14 11 11 35 3290 163 73 46 17 15 83 1900 2660 264 3350 459 163 108 196 106 12 15 6 3 • 9390 • 53 • 12 •5 •3 •2 •8 •4100 • 8620 •128 •14500 •335 • 53 •2S •74 •24 .52 .58 .22 .20 .1 .78 .52 .36 .36 .49 .25 .31 .4 .5 .6 .3 .5 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) JUNE • 300 •270 • 100 •540 • 150 • 140 •250 •490 • 520 •470 •660 • 500 •460 •400 •360 377 385 289 179 173 466 210 179 150 133 124 122 115 102 97 533 459 131 1200 212 196 412 1050 1140 995 1570 1080 165 155 145 138 660 371 95 76 1370 200 53 16 11 11 11 10 10 10 ___ •432 •335 •35 • 17SO • 86 •74 •278 • 1390 • 1600 • 1260 •2800 • 1460 •205 •167 •141 129 811 316 47 35 3230 123 27 6 3 3 3 3 2 2 - .3 .9 .6 .4 .1 .8 .6— 23J TOTAL 504.1 63.58 5750.9 37374.99 8711 16756.7 • Estimated 238 RIO GRANDB DB LOIZA BASIN 50051800 RIO GRANDB DB LOIZA AT HWY 183 NEAR SAN LORENZO, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCEN- DISCHARGB TRATION DAY (CFS) (MG/L) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL YEAR 92 80 78 99 127 81 76 92 95 83 134 98 80 79 90 86 179 111 132 159 123 270 134 116 192 127 116 105 98 96 96 3524 49094.0 JULY 10 10 10 73 154 55 23 93 59 17 167 71 23 17 18 19 287 108 147 253 164 776 130 63 217 138 99 88 79 55 39 —— SEDIMENT DISCHARGE (TONS /DAY) 2 2 2 38 63 13 4 27 17 3 79 22 4 3 4 4 191 32 61 107 53 767 49 21 148 50 30 25 21 14 10 1870 142271. .5 .2 .1 .5 .8 .9 .7 .1 .3 .1 60 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AUGUST 100 100 109 104 592 273 192 157 160 241 161 168 130 157 142 116 103 92 85 85 79 76 74 85 73 70 79 70 78 65 84 39 41 89 138 2490 811 484 238 246 324 196 174 160 216 291 143 436 23 25 28 30 41 64 73 52 28 29 34 37 36 40 10 12 26 40 5600 653 235 106 122 221 83 76 54 94 119 45 125 S S 6 6 8 13 16 10 5 6 6 8 6 9 .8 .8 .3 .6 .5 .5 .3 .5 .3 .5 .1 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) SEPTEMBER 75 64 103 71 61 76 73 59 177 72 60 54 49 47 48 075 0420 0110 0800 02500 01400 0230 180 153 137 126 117 106 103 100 73 106 129 35 28 27 23 20 252 73 44 32 22 22 37 74 245 209 453 418 350 196 41 18 20 31 44 49 40 26 14 19 42 7 4 5 4 3 159 16 7 4 2 2 4 015 0278 062 0977 02820 01320 0123 20 7 7 10 14 14 11 7 .6 .7 .0 .5 .5 .2 .7 .9 .7 .7 .4 .1 .1 4100 7735.2 7646 5983.1 0 Estimated RIO GRANDB DB LOIZA BASIN 50051800 RIO GRANDB DB LOIZA AT HWY 183 NEAR SAN LORBNZO, PR--Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 PARTICLB-SIZB DISTRIBUTION OF SUSPENDED SEDIMENT 239 DATE NOV 1991 08. .. JAN 1992 05... MAY 16... JUN 21... SEP 05... DATE NOV 1991 08. . . JAN 1992 05... MAY 16... JUN 21... SEP 05... TIME 2056 1936 1616 0535 1905 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .016 MM 45 36 40 41 37 DIS- CHARGE, INST. CUBIC FEET PER SECOND 1190 27800 e600 2110 2500 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM 55 44 50 52 44 SEDI- MENT, SUS- PENDED (MG/L) 4460 17300 11700 7360 6300 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 75 55 67 70 58 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 14300 1300000 e!8900 41900 42500 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 90 77 86 87 77 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM 21 19 22 18 19 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 97 92 97 96 90 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM 29 24 27 26 23 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 99 98 99 99 98 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 35 29 31 30 27 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 100 99 100 100 99 240 RIO ORANDB DB LOIZA BASIN 50051800 RIO ORANDB DB LOIZA AT HWY 183 NEAR SAN LORBNZO, PR—Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 SILT AND CLAY PERCENT OF SUSPENDED SBDIHBNT DATE NOV 1991 08... 08.. . 24.. . JAN 1992 05... 05.. . 06... FEB 25... JDN 21.. . 21... JUL 17... 22... AOG 05.. . 05.. . 05.. . 05... 05... TIME 1641 2141 1040 1806 2236 1220 0945 0505 0720 0927 1030 0925 0940 1155 2020 2205 STREAM- FLOW, INSTAN- TANEOUS (CFS) 2080 8130 308 3900 8080 634 14 2550 854 295 476 461 407 323 2040 1080 SEDI- MENT, SUS- PENDED (MO/L) 5420 3810 999 7410 1160 540 172 6280 3000 942 2560 3010 4390 2790 5490 2210 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 30400 83670 831 78100 25400 925 6.5 43300 6890 750 3290 3750 4820 2430 30270 6450 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 66 81 87 65 99 82 94 56 86 72 86 83 74 89 57 100 RIO GRANDB DB LOIZA BASIN 50053025 RIO TURABO ABOVE BORINQOBN, PR 241 LOCATION.--Lat 18°09'35-, long 66°02'26-, Hydrologic Onit 21010005, on left bank at Highway 765, 1.2 mi (1.9 km) south of Villa Borinquen, 8.1 mi (13.0 km) upstream from Rio Grande de Loisa. DRAINAGE ARBA.--7.14 mi 1 (18.49 km1 ). HATER-DISCHARGE RECORDS PERIOD OF RECORD.--January 1990 to current year. GAGE.—Hater-stage recorder and crest-stage gage. Elevation of gage is 492 ft (150 m), from topographic map. REMARKS.--Records fair except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JOL AOG SEP 1 16 8.2 2 37 8.1 3 17 8.4 4 15 8.4 5 13 8.6 6 11 8.2 7 11 133 8 10 227 9 13 111 10 11 52 11 9.7 25 12 14 e21 13 9.7 18 14 9.4 16 15 8.8 14 16 8.9 21 17 9.5 17 18 9.2 15 19 8.5 14 20 8.0 13 21 8.1 20 22 8.4 37 23 8.3 20 24 7.9 127 25 8.0 32 26 7.9 22 27 7.3 47 28 7.3 38 29 7.3 27 30 7.3 21 31 7.3 TOTAL 334.8 1137.9 MEAN 10.8 37.9 MAX 37 227 MIN 7.3 8.1 AC-FT 664 2260 CFSM 1.51 5.31 IN. 1.74 5.93 e Estimated STATISTICS OF MONTHLY MEAN MEAN 29.5 28.3 MAX 48.2 37.9 (WY) 1991 1992 MIN 10.8 18.7 (WY) 1992 1991 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN- DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 18 17 21 23 18 16 15 15 14 14 13 14 13 13 e!3 15 13 13 13 24 18 14 13 13 13 12 12 12 12 13 14 461 14.9 24 12 914 2.08 2.40 DATA 19.0 23.1 1991 14.9 1992 FOR 13 12 12 12 605 328 31 13 8.8 11 8.6 9.7 12 14 18 43 47 27 24 22 21 19 19 19 20 19 17 20 17 16 15 1473.1 47.5 605 8.6 2920 6.66 7.67 FOR WATER 23.6 47.5 1992 7.85 1990 14 14 14 15 13 29 23 18 16 21 17 15 13 14 15 12 12 11 12 11 11 12 12 12 12 16 12 11 11 ___ —— 418 14.4 29 11 829 2.02 2.18 YEARS 1990 13.8 18.1 1991 8.93 1990 10 11 10 10 10 11 10 10 9.0 9.0 8.6 8.4 8.6 9.3 9.9 8.6 19 11 9.0 8.6 8.6 8.5 7.5 7.5 7.3 6.8 6.8 6.6 6.2 6.2 7.0 280.0 9.03 19 6.2 555 1.27 1.46 - 1992 10.7 11.6 1991 9.03 1992 1991 CALENDAR YEAR 5768. 15. 277 4. 4. 11440 2. 30. 21 9. 5. 1 8 Jul 16 4 Aug 8 4 Aug 8 21 05 1 7 7.3 6.3 5.9 5.7 5.5 5.8 9.8 8.0 6.9 6.7 8.2 34 13 15 10 7.5 6.8 6.9 24 18 7.7 7.0 6.3 5.9 5.7 5.4 5.4 5.4 5.1 5.6 --- 270.8 9.03 34 5.1 537 1.26 1.41 15 37 8.3 6.2 5.9 11 10 7.2 6.2 6.2 7.0 7.7 7.9 6.3 9.0 88 16 10 8.3 24 11 8.6 150 151 49 134 40 19 14 40 15 928.8 30.0 151 5.9 1840 4.20 4.84 65 29 24 68 26 22 29 40 27 114 e!25 149 elOl e69 44 36 82 37 26 24 137 37 28 23 20 19 18 16 15 16 1466 48.9 149 15 2910 6.84 7.64 14 14 14 13 15 12 11 16 14 12 20 13 11 11 11 12 34 12 17 19 13 34 16 12 39 16 13 12 11 12 11 484 15.6 39 11 960 2.19 2.52 11 13 14 14 183 62 28 22 18 22 20 21 17 24 19 16 15 12 12 12 11 10 10 11 10 16 13 11 11 9.8 12 679.8 21.9 183 9.8 1350 3.07 3.54 9.9 10 17 11 9.3 11 11 11 43 12 9.6 8.7 8.2 7.9 7.5 34 27 17 87 205 147 33 21 17 14 13 11 10 9.5 9.4 842.0 28.1 205 7.5 1670 3.93 4.39 , BY WATER YEAR (WY) 7.37 9.03 1992 6.18 1990 FOR 1992 8776 24 605 5 5 3590 14 5 17410 3 45 37 13 7 16.6 30.0 1992 8.99 1990 WATER YEAR .2 .0 Jan 5 .1 Apr 29 .5 Apr 24 Jan 5 . 37 Jan 5 .1 Apr 29 .36 .72 .3 26.2 48.9 1992 9.59 1991 18.5 21.2 1991 15.6 1992 WATER 21 24 18 605 4 4 3590 14 3 15240 2 40 31 10 5 18.2 21.9 1992 10.8 1991 YEARS 1990 .0 .0 .1 Jan .1 May .4 Aug Jan .37 Jan .9 May .95 .04 .7 21.4 28.1 1992 14.1 1990 - 1992 1992 1991 5 1992 23 1990 8 1991 5 1992 5 1992 22 1990 RIO GRANDB DB LOIZA BASIN 50053025 RIO TURABO ABOVE BORINQUBN, PR—Continued WATER-QUALITY RECORDS PERIOD OF RECORDS.-- Water years 1990 to current year. INSTRUMENTATION.-- DH-48 and automatic sediment sampler. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: January 1990 to September 1992 EXTREMES FOR PERIOD OP DAILY RECORD.-- SEDIMENT CONCENTRATION: Maximum daily mean, 955 mg/L Jan. 05, 1992; Minimum daily mean, 1 mg/L Several days. SEDIMENT LOADS: Maximum daily mean, 4,920 tons (4,460 tonnes) Jan. 05, 1992; Minimum daily mean, 0.01 ton (0.01 tonne) Several days. EXTREMES FOR WATER YEARS 1990-92.-- 242 Water Suspended- sediment concentration (mg/L) Year 1990 1991 1992 maximum 469 (May, 294 (Oct. 955 (Jan. 10) 3 21) 1 05) 1 minimum (Several days) (Several days) (Several days) SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY) DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CPS) e7.6 e7.4 e6.4 e6.0 e6.2 e6.4 e6.6 e6.2 e6.4 e7.4 e6.8 e6.2 e6.0 e5.8 e5.6 e5.6 e5.4 e6.0 6.8 14 7.4 6.1 5.9 6.6 7.5 26 12 13 9.0 7.8 7.4 MEAN CONCEN- TRATION (MG/L) JANUARY ___ ___ ___ ___ --- ___ ___ ___ ___ --- ___ ___ __- ___ --- ___ ___ ___ 6 13 7 5 5 6 7 25 14 11 8 6 6 SEDIMENT DISCHARGE (TONS/ DAY) ___ ___ ___ ___ --- ___ _-_ ___ ___ --- ___ ___ _._ ___ --- ___ ___ ___ .10 .79 .15 .09 .09 .10 .15 2.5 .47 .36 .23 .14 .12 MEAN DISCHARGE (CFS) 6.9 7.7 6.8 6.3 6.2 6.1 6.3 8.3 9.4 8.3 6.8 6.4 6.0 11 7.7 6.9 6.7 7.6 6.7 7.9 12 11 12 35 10 8.5 7.7 7.8 ___ ___ -__ Suspended- sediment discharge maximum 220 598 4,920 (Jun. 14) (Sep. 17) (Jan. 05) (tons per day) minimum .04 (Several .01 ( Several .02 (Several days) days) days) , WATER YEAR OCTOBER 1989 TO SEPTEMBER 1990 MEAN CONCEN- TRATION (MG/L) FEBRUARY 6 6 6 5 5 5 6 7 9 7 6 6 6 7 7 6 6 6 6 7 12 10 11 32 9 7 7 7 ___ ___ ___ SEDIMENT DISCHARGE (TONS /DAY) .12 .12 .10 .09 .09 .09 .11 .16 .22 .18 .11 .10 .10 .21 .16 .12 .10 .12 .10 .16 .42 .31 .51 5.2 .26 .18 .15 .15 ___ ___ ___ MEAN DISCHARGE (CFS) 8. 7. 6. 6. 6. 6. 6. 6. 8. 8. 10 22 34 80 15 16 12 8. 7. 6. 6. 6. 6. 6. 6. 6. 6. 6. 6. 6. 6. 2 6 8 7 5 3 2 2 4 3 8 4 9 7 3 3 2 1 1 0 2 0 5 1 MEAN CONCEN- TRATION (MG/L) MARCH 7 6 6 6 6 6 6 6 7 8 10 21 30 77 13 15 11 7 6 6 6 6 5 5 5 5 5 5 5 5 5 SEDIMENT DISCHARGE (TONS/DAY) .16 .14 .11 .10 .10 .10 .10 .10 .15 .19 .32 1.5 3.6 32 .55 .80 .37 .17 .13 .12 .11 .10 .08 .08 .08 .08 .08 .08 .08 .08 .08 TOTAL 243.5 250.0 9.74 351.8 41.74 e Estimated RIO GRANDE DB LOIZA BASIN 243 50053025 RIO TURABO ABOVE BORINQ0BN, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1989 TO SEPTEMBER 1990 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 (CFS) 5 5 5 5 5 5 4 5 4 5 4 5 8 6 5 5 5 5 7 6 5 5 5 4 11 16 8 6 5 5 - (MG/L) APRIL (TONS/ DAY) .6 5 .08 .4 5 .08 .3 5 .07 .2 5 .06 .1 5 .06 . 1 5 .06 .9 5 .06 .0 5 .06 .9 5 .06 .1 5 .06 .9 4 .06 . 1 3 .05 .9 3 .09 .4 . 5 .2 . 1 . 1 .0 . 6 .3 .2 .3 . 9 .07 .06 .06 .06 .06 .08 .07 .06 .06 .05 .05 11 .65 16 1.0 .9 10 .28 .3 6 .11 .6 6 .08 .4 5 .07 __ ___ MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MAY 5.4 5.3 5.2 5.4 5.5 5.3 5.2 5.3 1 9 3 7.3 5.9 8.9 6.2 5.4 5.2 5.0 .9 .8 .7 .4 .1 .1 .1 .9 .9 .6 4.6 4.4 4.6 5 5 4 4 4 5 5 6 84 469 25 17 13 7 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 .06 .06 .06 .06 .06 .06 .07 .08 126 35 .96 .34 .20 .18 .08 .06 .06 .06 .05 .04 .04 .04 .04 .04 .04 .06 .06 .04 .04 .04 .04 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) JUNE 4.9 5.4 4.9 5.8 6.2 6.3 8.0 6.0 11 €.9 6.6 6.6 6.3 162 92 17 11 8.3 7.8 10 7.9 6.8 7.1 10 99 37 14 10 8.3 8.1 5 5 5 6 10 13 13 11 8 7 7 7 7 161 91 16 11 10 8 8 7 7 7 7 100 33 13 10 7 7 .06 .08 .06 .10 .16 .21 .27 .18 .25 .14 .12 .12 .12 220 41 .81 .31 .22 .18 .21 .If .1? .13 .18 56 4.3 .50 .28 .17 .15 TOTAL 185.3 3.72 278.6 164.02 601.2 326.59 244 RIO GRANDS OS I/OIZA BASIN 50053025 RIO TURABO ABOVE BORINQUBN, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1989 TO SEPTEMBER 1990 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CPS) (MG/L) (TONS/DAY) JULY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 15 9.8 8.7 14 9.1 15 12 9.9 8.6 8.9 7.9 8.1 8.3 9.2 20 12 20 24 50 15 11 11 12 13 101 92 19 12 9.4 8.1 7.2 15 9 7 13 8 15 11 9 8 7 7 7 8 8 19 27 31 23 46 10 4 4 4 6 115 91 14 6 5 5 5 .79 .25 .18 .70 .20 .79 .36 .25 .20 .18 .15 .14 .17 .21 2.1 .89 1.9 4.3 11 .41 .13 .11 .13 .22 76 79 .83 .21 .13 .11 .09 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AUGUST 6.9 8.2 7.5 8.7 11 7.7 11 30 13 178 30 15 13 11 9.7 8.7 8.1 8.2 9.0 8.1 14 18 12 11 9.2 8.4 7.4 96 67 19 12 4 4 3 3 3 3 9 28 11 176 27 10 7 7 7 8 10 10 10 10 16 18 11 9 12 8 6 96 73 18 11 .08 .09 .08 .08 .09 .07 .42 3.2 .39 184 2.8 .40 .26 .21 .19 .20 .21 .22 .23 .22 1.2 1.5 .41 .28 .31 .19 .12 107 37 1.1 .33 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) SEPTEMBER 14 11 9.8 13 9.0 8.4 11 9.8 8.8 8.2 7.9 8.4 9.0 9.8 9.2 13 11 23 12 9.1 8.9 8.7 10 9.8 26 14 9.7 9.1 8.4 104 12 11 8 12 8 7 9 10 10 8 8 8 7 8 13 14 10 24 6 6 6 6 6 7 23 14 12 12 12 107 .72 .35 .21 .53 .20 .18 .27 .27 .23 .18 .17 .19 .19 .22 .32 .50 .28 2.8 .25 .15 .13 .13 .17 .19 5.4 .79 .34 .31 .28 142 TOTAL 581.2 182.13 676.8 342.88 424.0 157.95 RIO GRANDB DE LOIZA BASIN 50053025 RIO TORABO ABOVE BORINQOEN, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 245 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) OCTOBER 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 13 8.0 8.4 7.7 6.5 6.1 6.4 7.4 6.4 8.3 7.4 6.3 22 30 25 148 e45 e60 e70 eSO e300 42 33 64 126 204 80 37 26 22 19 21 13 14 13 11 10 10 10 25 30 30 30 30 29 23 138 40 53 62 44 294 36 31 64 125 206 50 12 12 12 7 .74 .28 .32 .27 .20 .16 .18 .20 .43 .68 .60 .52 1.8 2.3 1.6 55 e4.9 e8.6 el2 5.9 e238 3.9 2.8 34 88 192 19 1.2 .86 .71 .37 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) NOVEMBER TOTAL 1494.9 677.52 18 17 16 63 55 26 21 19 17 16 15 15 15 14 14 14 14 13 13 13 14 16 13 12 12 14 19 15 15 22 560 8 9 10 58 54 22 12 11 9 7 6 6 5 5 5 5 5 5 6 7 8 10 8 6 5 5 13 12 12 11 .41 .42 .44 43 27 1.7 .66 .54 .41 .29 .24 .24 .20 .18 .18 .18 .18 .20 .24 .25 .34 .42 .31 .19 .17 .18 .93 .46 .50 .62 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) DECEMBER 17 16 36 22 16 15 14 13 13 13 13 13 12 87 35 18 15 14 13 12 12 12 11 11 11 11 10 10 12 15 195 10 10 31 11 7 5 5 5 5 5 3 3 4 85 33 16 10 10 10 9 7 5 5 7 12 15 14 11 8 11 195 .51 .42 5.6 .63 .32 .23 .19 .18 .18 .18 .10 .12 .15 34 7.3 .85 .39 .37 .36 .31 .23 .17 .14 .22 .36 .41 .38 .29 .26 .58 187 81.08 717 242.43 e Estimated 246 RIO GRANDB DB LOIZA BASIN 50053025 RIO TURABO ABOVE BORINQOEN, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CPS) (MG/L) (TONS/DAY) JANUARY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 29 19 16 13 45 21 19 21 21 21 18 17 15 15 17 15 13 12 11 11 11 11 11 9.9 9.1 9.0 8.9 9.6 9.3 9.2 12 23 5 5 5 42 19 17 24 35 40 35 24 12 7 7 7 7 7 8 11 23 25 21 16 11 6 5 4 4 4 5 2.1 .26 .20 .18 25 1.2 .77 1.5 1.9 2.2 1.8 1.0 .50 .28 .30 .27 .23 .22 .26 .30 .67 .74 .61 .42 .26 .15 .13 .11 .10 .11 .15 FEBRUARY 11 9.8 10 10 19 14 12 11 9.8 12 32 97 41 19 15 13 12 13 17 18 19 15 14 14 13 12 12 12 5 5 5 5 17 16 13 11 10 11 31 96 33 12 12 12 12 11 10 7 6 5 5 5 5 5 6 7 .16 .13 .13 .13 1.9 .62 .42 .31 .26 .34 4.1 85 6.1 .59 .47 .42 .39 .38 .43 .34 .30 .23 .18 .18 .18 .17 .18 .24 MEAN DISCHARGE (CPS) 12 11 11 16 13 18 20 15 12 11 11 10 9.7 10 9.1 8.5 8.0 9.1 10 8.5 7.6 12 9.5 7.4 7.3 43 9.7 8.1 7.6 7.4 6.9 MEAN CONCEN- TRATION (MG/L) MARCH 8 9 9 9 10 10 11 12 13 13 12 8 6 4 3 3 3 3 3 4 5 7 8 8 6 4 7 14 15 13 12 SEDIMENT DISCHARGE (TONS/DAY) .29 .28 .28 .38 .36 .45 .57 .45 .44 .40 .34 .24 .16 .12 .09 .07 .06 .07 .09 .10 .12 .21 .21 .17 .11 .46 .17 .30 .29 .25 .22 TOTAL 479.0 43.92 506.6 104.28 359.4 7.75 RIO GRANDS DB LOIZA BASIN 50053025 RIO TURABO ABOVE BORINQOBN, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 247 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 6.9 6.7 6.6 6.6 6.6 6.6 6.5 10 7.5 10 7.6 7.9 7.2 6.9 e8.4 8.2 6.9 7.1 6.4 6.3 6.3 6.3 6.2 6.1 5.9 6.3 6.2 5.7 5.7 5.7 ___ APRIL 10 8 8 8 8 8 10 11 9 7 7 7 9 10 12 18 17 13 8 8 8 8 8 9 10 10 7 6 6 6 ___ .18 .15 .14 .14 .14 .14 .17 .30 .18 .18 .15 .16 .17 .18 e.28 .39 .33 .23 .15 .14 .14 .14 .13 .14 .17 .18 .12 .10 .10 .10 .__ MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MAY 5.7 5.7 5.7 7.1 6.3 6.1 5.7 5.7 6.3 6.1 21 11 6.1 5.8 6.0 5.8 5.5 6.9 6.3 6.0 6.5 6.8 5.9 5.4 130 11 7.8 7.0 6.6 6.6 6.4 10 12 12 11 7 3 1 1 1 1 18 5 1 1 1 1 1 1 1 1 1 1 1 1 136 11 9 10 8 4 1 .15 .18 .18 .20 .12 .06 .03 .02 .02 .01 5.6 .17 .03 .02 .02 .02 .02 .01 .01 .02 .01 .02 .02 .02 137 .36 .19 .18 .14 .07 .02 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) TOTAL 207.3 5.22 340.8 144.92 6.2 6.5 6.2 6.0 6.4 7.7 7.6 6.9 6.7 6.3 8.3 19 8.3 7.3 6.7 6.1 6.2 6.0 5.8 5.7 6.1 6.1 5.8 5.9 5.7 5.7 5.8 5.5 8.3 87 287.8 JUNE 1 1 1 1 1 1 1 1 1 1 2 13 4 4 5 4 3 1 1 1 1 1 1 1 1 1 1 2 7 82 .01 .02 .02 .02 .02 .01 .01 .02 .02 .02 .05 1.1 .09 .10 .10 .08 .05 .03 .02 .02 .02 .02 .02 .02 .02 .02 .03 .03 .20 92 94.19 e Estimated 248 RIO GRANDB DB LOIZA BASIN 50053025 RIO TORABO ABOVE BORINQUEN, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL YEAR 102 14 9.4 8.5 7.6 7.4 6.8 6.3 6.4 6.3 6.2 5.7 5.6 5.1 68 277 19 10 8.6 7.7 6.3 6.2 6.0 8.0 6.1 5.7 5.7 5.4 5.1 8.0 6.0 656.1 6606.3 JULY 153 66 19 14 8 5 3 2 1 1 1 1 1 1 66 228 5 2 2 2 1 1 1 1 1 1 1 1 1 1 3 ... MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AUGUST 77 2.8 .51 .33 .16 .10 .07 .05 .03 .02 .02 .02 .02 .02 71 374 .32 .06 .04 .04 .03 .01 .01 .03 .02 .02 .02 .02 .02 .02 .06 526.87 2698.80 5.1 5.1 5.1 .8 .9 .9 .8 . . • . . . .7 4.7 7.1 7.6 5.7 4.4 5.3 62 13 7.3 6.1 5.5 91 21 9.2 7.4 6.5 334.0 2 1 1 1 1 1 2 2 2 2 1 1 1 1 2 4 5 7 10 13 14 63 12 6 5 5 87 21 10 11 11 ... .03 .02 .02 .02 .02 .02 .02 .03 .03 .03 .02 .02 .02 .02 .03 .05 .10 .13 .13 .15 .20 39 .57 .13 .09 .07 70 1.6 .25 .21 .21 113.24 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) SEPTEMBER 6.2 7.4 5.7 5.4 5.4 5.7 5.6 5.3 11 7.3 7.5 6.3 6.0 6.0 5.7 5.7 240 20 18 12 11 52 37 17 12 10 9.2 32 69 22 12 12 12 13 13 14 14 15 15 17 17 15 13 8 7 7 250 20 17 12 9 50 28 15 8 8 8 29 67 21 .20 .26 .18 .18 .18 .20 .21 .21 .45 .34 .35 .28 .22 .13 .10 .10 598 1.3 1.0 .43 .27 19 2.9 .79 .26 .22 .22 5.1 23 1.3 663.4 657.38 RIO GRANDB DB LOIZA BASIN 50053025 RIO TURABO ABOVE BORINQUBN, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) NOVEMBER 249 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) OCTOBER 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 16 37 17 15 13 11 11 10 13 11 9.7 14 9.7 9.4 8.8 8.9 9.5 9.2 8.5 8.0 8.1 8.4 8.3 7.9 8.0 7.9 7.3 7.3 7.3 7.3 7.3 15 112 15 9 4 12 24 30 21 11 10 20 6 3 2 2 2 1 1 1 2 3 4 7 11 12 12 11 10 10 11 .65 16 .68 .38 .12 .36 .67 .80 .74 .31 .25 1.1 .17 .07 .04 .05 .04 .03 .02 .02 .04 .06 .08 .16 .23 .24 .23 .22 .19 .19 .21 8.2 8.1 8.4 8.4 8.6 8.2 133 227 111 52 25 c21 18 16 14 21 17 15 14 13 20 37 20 127 32 22 47 38 27 21 12 12 10 9 10 10 206 334 143 25 5 5 5 5 5 47 16 12 7 5 14 36 10 174 40 24 63 46 35 25 .28 .27 .22 .21 .23 .24 160 416 65 5.8 .39 c.26 .23 .22 .20 5.2 .74 .45 .28 .18 2.1 5.5 .54 134 3.6 1.5 8.4 4.8 2.5 1.5 MEAN DISCHARGE (CFS) 18 17 21 23 18 16 15 15 14 14 13 14 13 13 el3 15 13 13 13 24 18 14 13 13 13 12 12 12 12 13 14 MEAN CONCEN- TRATION (MG/L) DECEMBER 15 11 10 9 8 7 9 9 6 4 5 7 8 10 10 10 10 10 10 24 15 5 2 3 4 3 5 10 11 12 12 SEDIMENT DISCHARGE (TONS/DAY) .77 .47 .55 .60 .38 .31 .36 .35 .23 .17 .20 .28 .30 .35 e.38 .43 .37 .34 .34 3.0 .88 .20 .06 .12 .15 .10 .17 .30 .34 .39 .47 TOTAL 334.8 24.35 1137.9 820.84 461 13.36 e Estimated 250 RIO GRANDB DB LOIZA BASIN 50053025 RIO TURABO ABOVE BORINQUEN, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/Ii) (TONS/DAY) MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) JANUARY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 13 12 12 12 605 328 31 13 8.8 11 8.6 9.7 12 14 18 43 47 27 24 22 21 19 19 19 20 19 17 20 17 16 15 13 13 12 13 955 854 34 14 13 16 18 20 21 23 21 56 38 10 16 20 18 14 6 5 5 4 4 17 7 3 4 .47 .43 .40 .39 4920 1010 4.0 .50 .33 .49 .43 .53 .72 .84 .99 20 10 .71 1.0 1.2 .99 .71 .34 .26 .24 .20 .18 1.1 .33 .12 .16 FEBRUARY 14 14 14 15 13 29 23 18 16 21 17 15 13 14 15 12 12 11 12 11 11 12 12 12 12 16 12 11 11 7 10 11 11 10 30 21 11 10 5 4 4 4 3 5 6 7 8 7 5 5 5 5 6 7 8 8 7 6 .30 .40 .41 .42 .38 3.4 1.5 .52 .43 .31 .19 .17 .15 .13 .21 .23 .24 .25 .22 .16 .14 .17 .18 .22 .23 .39 .28 .22 .17 MEAN DISCHARGE (CFS) 10 11 10 10 10 11 10 10 9.0 9.0 8.6 8.4 8.6 9.3 9.9 8.6 19 11 9.0 8.6 8.6 8.5 7.5 7.5 7.3 6.8 6.8 6.6 6.2 6.2 7.0 MEAN CONCEN- TRATION (MG/L) MARCH 4 4 2 3 5 7 7 5 4 7 12 16 20 21 24 23 28 26 21 20 15 7 6 9 11 13 16 15 14 12 10 SEDIMENT DISCHARGE (TONS/ DAY) .12 .11 .08 .11 .15 .20 .21 .16 .11 .17 .26 .37 .45 .55 .60 .52 1.8 .79 .51 .46 .34 .17 .13 .18 .20 .24 .28 .26 .23 .19 .18 TOTAL 1473.1 5978.06 418 12.02 280.0 10.13 RIO GRANDB DB LOIZA BASIN 50053025 RIO TURABO ABOVE BORINQUBN, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 251 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 7.3 6.3 5.9 5.7 5.5 5.8 9.8 8.0 6.9 6.7 8.2 34 13 15 10 7.5 6.8 6.9 24 18 7.7 7.0 6.3 5.9 5.7 5.4 5.4 5.4 5.1 5.6 APRIL 10 10 10 9 10 10 11 11 13 13 15 38 26 22 13 8 10 16 43 24 13 8 5 4 4 4 7 10 13 18 ___ MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MAY .22 .16 .15 .14 .14 .15 .27 .26 .24 .23 .36 4.6 .97 .86 .39 .17 .17 .29 11 1.8 .26 .15 .09 .07 .06 .07 .11 .14 .17 .26 ___ 15 37 8.3 6.2 5.9 11 10 7.2 6.2 6.2 7.0 7.7 7.9 6.3 9.0 88 16 10 8.3 24 11 8.6 150 151 49 134 40 19 14 40 15 31 93 11 6 6 9 13 18 26 30 27 21 18 17 12 166 36 39 40 53 32 22 247 211 55 202 130 23 10 49 14 5.4 16 .27 .11 .09 .28 .35 .35 .43 .49 .51 .45 .40 .27 .29 177 1.7 .98 .89 7.6 1.1 .50 417 144 8.8 173 15 1.4 .36 18 .61 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/ DAY) JUNE 65 29 24 68 26 22 29 40 27 114 e!25 149 elOl e69 44 36 82 37 26 24 137 37 28 23 20 19 18 16 15 16 93 124 26 95 24 17 33 47 27 166 197 294 144 89 50 36 109 31 24 22 245 23 10 8 7 7 7 7 7 7 70 9.8 2.2 46 1.8 1.1 5.1 6.8 2.1 74 e99 136 e61 e!9 6.3 3.7 66 3.2 1.6 1.4 346 2.7 .74 .50 .41 .37 .34 .31 .28 .29 TOTAL 270.8 23.95 928.8 993.63 1466 968.04 e Bstiaated 252 RIO GRANDS DB LOIZA BASIN 50053025 RIO T0RABO ABOVE BORINQOEN. PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL YEAR 14 14 14 13 15 12 11 16 14 12 20 13 11 11 11 12 34 12 17 19 13 34 16 12 39 16 13 12 11 12 11 484 8776.2 JULY 6 5 5 5 6 12 17 21 19 18 40 43 35 28 21 13 43 10 22 45 35 47 12 10 47 10 10 10 10 12 12 ... MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AUGUST .23 .20 .18 .17 .24 .37 .51 .95 .71 .56 2.8 1.6 1.1 .85 .65 .43 12 .35 1.2 2.3 1.2 11 .48 .33 11 .40 .35 .29 .31 .37 .36 53.49 10787.03 11 13 14 14 183 62 28 22 18 22 20 21 17 24 19 16 15 12 12 12 11 10 10 11 10 16 13 11 11 9.8 12 679.8 10 9 18 14 317 80 16 11 10 8 7 9 8 22 25 24 19 13 8 5 4 3 3 3 3 12 10 7 6 8 9 ... .30 .33 .73 .56 613 22 1.2 .66 .49 .44 .43 .52 .39 2.1 1.3 1.0 .80 .40 .25 .17 .12 .09 .08 .09 .08 .94 .35 .20 .18 .20 .29 649.69 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) SEPTEMBER 9.9 10 17 11 9.3 11 11 11 43 12 9.6 8.7 8.2 7.9 7.5 34 27 17 87 205 147 33 21 17 14 13 11 10 9.5 9.4 842.0 8 9 11 13 15 16 13 12 51 11 9 7 8 10 11 43 31 15 391 326 191 6 5 3 4 5 8 10 10 10 --- ... .22 .25 .52 .38 .39 .48 .42 .98 13 .34 .23 .18 .18 .20 .21 15 3.4 .67 164 815 221 .60 .28 .16 .15 .18 .27 .27 .25 .26 --- 1239.47 RIO GRANDB DB LOIZA BASIN 50053025 RIO TURABO ABOVE BORINQUBN, PR--Continued WATER QUALITY DATA, WATER YEARS DECEMBER 1990 TO SEPTEMBER 1992 PARTICLB-SIZB DISTRIBUTION OF SUSPENDED SEDIMENT 253 DATE DEC 1990 14... JAN 1992 05. .. DIS- CHARGE, INST. CUBIC PBBT TIME PER SECOND 1330 95 1656 1350 SEDI- MENT, SUS- PENDED (MG/L) 1930 13600 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 495 49600 SBD. SUSP. PALL DIAM. PERCENT FINER THAN .002 MM 55 29 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM 65 44 SBD. SUSP. PALL DIAM. PERCENT FINER THAN .008 MM 69 57 DATE DEC 1990 14... JAN 1992 05. . . SBD. SUSP. PALL DIAM. PERCENT FINER THAN .016 MM 78 75 SBD. SUSP. PALL DIAM. PERCENT FINER THAN .031 MM 84 78 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 98 83 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 99 90 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 99.4 94 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 99.8 97 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 100 99 254 RIO GRANDB OB LOIZA BASIN 50053025 RIO TURABO ABOVE BORINQUBN, PR—Continued WATER QDALITY DATA, WATBR YEAR OCTOBER 1991 TO SEPTEMBER 1992 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT DATE OCT 1991 02... JAN 1992 05... 16... MAY 14.. . JUN 03... AUG 04... SEP 19.. . TIME 1015 1711 1648 1520 1445 1200 2056 STREAM- FLOW, INSTAN- TANEOUS (CPS) 49 2340 29 14 49 12 96 SEDI- MENT, SUS- PENDED (MG/L) 193 4830 168 540 395 4080 1540 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 25 30600 13 20 52 132 399 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 98 82 98 96 99 100 98 RIO QRANDB DB LOIZA BASIN 50055000 RIO QRANDB DB LOIZA AT CAQUAS, PR 255 LOCATION.--Lat 18°14'33", long 66°00'34', Hydrologic Onlt 21010005, on right bank 250 ft (76 m) upstream from bridge on Highway 189, 1.2 mi (1.9 km) downstream from Rio Turabo, and 1.8 mi (2.9 km) east of Plaza d« Caguas. DRAINAGE AREA.--89.8 mi* (232.6 km*). WATER-DISCHARGE RECORDS PERIOD OP RECORD.—1959 (low-flow measurement only), February to November 1959 (monthly measurements only), December 1959 to current year. GAOB.—Water-stage recorder. Datum of gage is 143.28 ft (43.672 m) above mean sea level. REMARKS.--Records good. Gage-height and precipitation satellite telemetry at station. DAY DISCHARGE, CUBIC FEET PBR SECOND, WATER YBAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES OCT NOV DEC JAN PBB MAR APR MAY OUN JOL AUG SBP 1 304 68 2 466 80 3 301 72 4 195 63 5 174 101 6 166 118 7 113 1130 8 99 4110 9 98 1640 10 102 696 11 88 292 12 126 219 13 107 194 14 86 160 15 87 136 16 83 145 17 100 159 18 82 119 19 79 105 20 66 98 21 63 112 22 102 454 23 77 186 24 65 641 25 58 329 26 52 187 27 51 423 28 49 313 29 181 272 30 241 191 31 104 TOTAL 3965 12813 MEAN 128 427 MAX 466 4110 MIN 49 63 AC-FT 7860 25410 CFSM 1.42 4.76 IN. 1.64 5.31 STATISTICS OF MONTHLY MEAN MEAN 388 316 MAX 1910 1131 (WY) 1971 1988 MIN 44.2 64.9 (WY) 1968 1968 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 157 152 154 216 151 126 115 109 113 105 96 99 95 94 83 94 93 78 75 90 174 83 77 73 71 69 68 68 74 68 96 3216 104 216 68 6380 1.16 1.33 DATA 233 714 1988 33.6 1968 FOR 106 78 72 68 7930 4920 609 311 246 282 198 171 164 144 135 149 219 132 119 115 110 110 106 110 109 113 101 100 103 93 91 17314 559 7930 68 34340 6.22 7.17 FOR WATER 148 559 1992 45.3 1968 91 87 89 96 92 108 143 100 86 121 97 82 76 76 90 84 71 68 66 65 62 60 68 69 68 64 70 64 58 ___ --- 2371 81.8 143 58 4700 .91 .98 YEARS 1960 111 291 1984 35.6 1968 56 53 57 55 60 62 58 109 59 51 48 45 47 47 65 48 50 82 56 60 55 54 48 44 41 41 40 39 49 40 38 1657 53.5 109 38 3290 .60 .69 - 1992 91.2 306 1989 23.2 1968 1991 CALENDAR YBAR 48124 132 4110 20 22 95450 1. 19. 218 72 29 NOV 8 Aug 13 Apr 28 47 94 52 53 38 36 36 33 42 45 39 37 39 72 108 60 81 49 42 41 59 145 75 48 47 38 35 35 32 30 31 35 --- 1513 50.4 145 30 3000 .56 .63 42 174 60 41 35 64 117 62 47 41 40 64 49 39 71 1090 214 106 74 146 101 63 1400 2020 333 2740 399 202 144 249 146 10373 335 2740 35 20570 3.73 4.30 521 479 177 922 265 196 184 207 221 436 442 1070 689 522 264 263 400 259 169 147 1020 234 179 144 127 116 113 110 97 93 —— 10066 336 1070 93 19970 3.74 4.17 89 81 78 77 146 84 74 84 98 77 141 108 76 69 76 82 222 100 93 146 106 364 118 89 171 105 82 75 66 62 66 3305 107 364 62 6560 1.19 1.37 66 66 76 63 1610 644 233 159 123 243 150 171 122 130 161 111 104 99 91 91 88 80 81 113 85 73 89 77 85 73 95 5452 176 1610 63 10810 1.96 2.26 87 72 104 93 80 89 89 73 280 103 78 70 63 61 60 99 284 165 746 2870 1660 335 207 161 135 121 113 103 102 102 —— 8605 287 2870 60 17070 3.19 3.56 , BY WATER YBAR (WY) 84.7 226 1985 38.0 1968 FOR 1992 80650 220 7930 30 34 43300 24 28 160000 2 33 312 95 48 254 863 1985 33.7 1974 WATER YBAR Jan 5 Apr 28 Apr 24 Jan 5 . 32 Jan 5 Apr 27 .45 .41 260 1283 1979 34.1 1975 223 660 1961 21.8 1974 WATER 220 526 82 17900 11 11 71500 31 159100 2 33 365 106 40 259 949 1979 53.6 1967 YEARS 1960 .3 Oct Apr Apr Sep . 17 Sep .45 .22 259 764 1979 37.4 1967 - 1992 1979 1967 9 1970 8 1968 8 1968 6 1960 6 1960 256 RIO GRANDS DB LOIZA BASIN 50055000 RIO GRANDS DB LOIZA AT CAGUAS, PR—Continued WATER-QUALITY RECORDS PERIOD OP RECORD.--Hater years 1959 to current year. PERIOD OP DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGEi October 1983 to September 1989. INSTRUMENTATION.— USD-49 and automatic sediment sampler. EXTREMES FOR PERIOD OP DAILY RECORD.-- SEDIMENT CONCENTRATIONi Maximum daily mean,14,500 mg/L Nov 27, 1987) Minimum daily mean, 8 •gr/L January 23, 1992. SEDIMENT LOADSi Maximum daily mean, 227,000 tons (205,890 tonnes) Nov 27, 1987; Minimum daily mean, 1.3 tons (1.2) July 14, 1985. EXTREMES POR CURRENT YBAR.-- SBDIMBNT CONCENTRATIONi Maximum daily mean, 2,790 mg/L January 05, 1992 ; minimum daily mean, 8 mg/L January 23, 1992. SEDIMENT LOADSi Maximum daily mean, 199,000 tons (180,000 tonnes) January 05, 1992; minimum daily 1.9 ton (1.7 tonnes) several days. HATER-QUALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 18. .. DEC 05... PBB 1992 27... MAY 18... JUN 11. .. AUG 19... TIME 1215 1445 1240 1155 0815 1125 DIS- CHARGE, INST. CUBIC FEET PER SECOND 80 145 71 102 702 84 SPE- CIFIC CON- DUCT- ANCE (US/CM) 242 219 262 200 144 228 PH HATER WHOLE FIELD (STAND- ARD UNITS) 7.8 7.6 7.3 7.4 7.1 7.4 TEMPER- ATURE HATER (DBG C) 28.5 24.0 26.5 27.5 25.5 29.5 TUR- BID- ITY (NTU) 28 170 45 31 170 7.8 OXYGEN, DIS- SOLVED (MG/L) 7.6 7.8 7.7 7.1 8.0 7.3 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 96 97 93 89 99 90 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 16 19 14 25 23 <10 COLI- PORM, PBCAL, 0.45 UM-MF (COLS./ 100 ML) 20000 20000 5400 25000 K4800 K1700 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 440 630 380 3000 23000 400 DATE OCT 1991 18.. . DEC 05... FBB 1992 27... MAY 18... JUN 11.. . AUG 19... HARD- NESS CALCIUM TOTAL DIS- (MG/L SOLVED AS (MG/L MAGNE- SIUM, DIS- SODIUM, DIS- SOLVED SOLVED (MG/L (MG/L CAC03) AS CA) AS MG) AS NA) 71 18 6.4 23 56 15 4.5 15 66 17 5.7 19 SODIUM AD- SORP- TION RATIO POTAS- SIUM, DIS- SOLVED (MG/L AS K) 2.0 0.9 2.5 1.9 ALKA- LINITY HAT WH TOT PET SULFIDB FIELD MG/L AS CACO3 75 66 84 90 40 74 SULPATB DIS- TOTAL SOLVED (MG/L (MO/L AS S) AS SO4) <0.5 9.6 <0.5 14 10 CHLO- RIDE, ois- SOLVBD (MG/L AS CL) 19 SOLIDS, RESIDUE DATE OCT 1991 18.. . DEC 05. .. PBB 1992 27... MAY 18.. . JUN 11.. . AUG 19... PLUO- RIDE, DIS- SOLVED (MG/L AS P) 0.10 -- -- 0.10 -- <0.10 SILICA, DIS- SOLVED (MG/L AS SI02) 35 -- -- 22 __ 29 SUM OP CONSTI- TUENTS, DIS- SOLVED (MG/L) 158 -- -- 122 __ 144 SOLIDS, DIS- SOLVED (TONS PER DAY) 34.1 -- -- 33.5 -- 32.7 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 18 495 51 12 219 11 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.370 0.480 0.350 0.550 0.350 0.250 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.050 0.070 0.050 0.030 0.070 0.020 NITRO- GEN, N02+N03 TOTAL (MG/L AS N) 0.420 0.550 0.400 0.580 0.420 0.270 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.090 0.070 0.110 0.140 0,050 0.060 NITRO- GEN, ORGANIC TOTAL (MG/L A* N) 0.51 0.23 0.19 0.46 0.35 0.14 K = non-ideal count RIO GRANDE DE LOIZA BASIN 50055000 RIO GRANDE DE LOIZA AT CAGOAS, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 257 DATE OCT 1991 18... DEC 05.. . FEB 1992 27... MAY 18... JON 11... AOG 19.. . DATE OCT 1991 18... DEC 05.. . FBB 1992 27... MAY 18.. . JON 11.. . AOG 19.. . NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.60 0.30 0.30 0.60 0.40 0.20 IRON, TOTAL RECOV- ERABLE (OG/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) 1.0 0.85 0.70 1.2 0.82 0.47 LEAD, TOTAL RECOV- ERABLE (OG/L AS PB) NITRO- GEN, TOTAL (MG/L AS NO3) 4.5 3.8 3.1 5.2 3.6 2.1 MANGA- NESE, TOTAL RECOV- ERABLE (OG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.300 0.290 0.210 0.160 0.100 0.150 MERCURY TOTAL RECOV- ERABLE (OG/L AS HG) ARSENIC TOTAL (OG/L AS AS) <1 — -- <1 -- -- SELE- NIUM, TOTAL (OG/L AS SB) BARIOM, TOTAL RECOV- ERABLE (OG/L AS BA) •clOO — — <100 — -- SILVER, TOTAL RECOV- ERABLE (DG/L AS AG) BORON, TOTAL RECOV- ERABLE (OG/L AS B) 10 -- -- 20 -- -- ZINC, TOTAL RECOV- ERABLE (DG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (OG/L AS CD) <1 — — <1 -- -- CYANIDE TOTAL (MG/L AS CN) CHRO- MIOM, TOTAL RECOV- ERABLE (OG/L AS CR) <1 -- — <1 -- -- PHENOLS TOTAL (DG/L) COPPER, TOTAL RECOV- ERABLE (OG/L AS CO) <10 — — 20 — -- MBTHY- LENB BLOB ACTIVE SOB- STANCE (MG/L) 1800 1300 180 150 0.10 <0.10 •cO.010 20 tO.010 0.01 0.05 258 RIO GRANDB DB LOIZA BASIN 50055000 RIO GRANDB DB LOIZA AT CAGDAS, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CPS) (MG/L) (TONS/DAY) OCTOBER 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 304 466 301 195 174 166 113 99 98 102 88 126 107 86 87 83 100 82 79 66 63 102 77 65 58 52 51 49 181 241 104 255 390 123 35 71 133 94 82 76 70 64 99 84 49 51 75 84 64 69 77 75 101 183 171 150 130 103 83 198 204 156 236 596 111 19 36 62 29 22 20 19 16 40 25 12 12 17 23 14 15 13 13 44 38 29 23 18 14 11 207 249 48 MEAN MEAN MEAN CONCBN- SEDIMENT MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) (CPS) (MG/L) (TONS/DAY) NOVEMBER 68 80 72 63 101 118 1130 4110 1640 696 292 219 194 160 136 145 159 119 105 98 112 454 186 641 329 187 423 313 272 191 ___ 122 82 62 55 97 99 1390 2080 1250 591 222 131 84 46 28 45 107 38 23 21 67 385 159 573 211 135 336 176 214 122 ___ 23 19 14 9.8 29 45 6250 40000 9130 1510 179 79 45 21 10 22 50 12 6.6 5.4 25 577 82 1490 219 70 469 163 164 65 DECEMBER 157 152 154 216 151 126 115 109 113 105 96 99 95 94 83 94 93 78 75 90 174 83 77 73 71 69 68 68 74 68 96 56 25 50 208 244 179 104 64 45 40 40 60 68 48 36 29 23 21 20 60 145 44 19 17 14 11 10 10 10 11 60 24 10 25 122 100 63 33 19 14 11 10 16 18 11 8.3 7.1 5.8 4.5 4.1 17 80 10 4.0 3.3 2.6 2.1 1.9 1.9 2.0 2.1 16 TOTAL 3965 2031 12813 60783.8 3216 648.7 RIO QRANDB DB LOIZA BASIN 259 50055000 RIO QRANDB DB LOIZA AT CAGUAS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN DISCHARGE DAY (CFS) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 106 78 72 68 7930 4920 609 311 246 282 198 171 164 144 135 149 219 132 119 115 110 110 106 110 109 113 101 100 103 93 91 MEAN MEAN MEAN CONCKN- SEDIMENT MEAN CONCEN- SEDIMENT MEAN CONCBN- SEDIMENT TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE (MG/L) (TONS/DAY) (CFS) (MG/L) (TONS/DAY) (CFS) (MG/L) (TONS/DAY) JANUARY 62 28 25 22 2790 2620 242 57 76 147 109 65 22 17 18 18 17 15 15 14 11 9 8 9 10 12 12 12 14 15 15 FEBRUARY 20 5.9 4.7 3.9 199000 44000 522 48 53 110 60 30 9.4 6.4 6.8 11 9.7 5.4 4.9 4.2 3.3 2.7 2.3 2.7 3.0 3.4 3.3 3.4 3.9 3.8 3.7 91 87 89 96 92 108 143 100 86 121 97 82 76 76 90 84 71 68 66 65 62 60 68 69 68 64 70 64 58 ___ ___ 16 17 28 35 31 88 114 79 76 104 53 45 41 40 63 105 138 153 158 160 158 153 146 137 127 117 105 86 69 ___ ___ 3.8 4.0 6.6 9.2 7.6 30 46 21 18 35 14 10 8.4 8.5 15 23 27 28 28 28 26 25 26 26 23 21 19 15 11___ ___ MARCH 56 53 57 55 60 62 58 109 59 51 48 45 47 47 65 48 50 82 56 60 55 54 48 44 41 41 40 39 49 40 38 60 58 56 55 55 55 52 120 92 75 57 40 37 40 47 53 60 68 59 50 47 45 42 39 41 41 39 33 27 26 26 9.0 8.2 8.5 8.4 9.1 9.5 8.2 39 15 10 7.2 4.9 4.5 5.1 7.8 6.6 8.3 15 8.9 8.0 7.0 6.4 5.5 4.5 4.5 4.5 4.2 3.5 3.6 2.8 2.6 TOTAL 17314 243950.8 2371 563.1 1657 250.3 260 RIO GRANDB OB LOIZA BASIN 50055000 RIO GRANDB OB LOIZA AT CAGOAS, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1993 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 IS 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 52 S3 38 36 36 33 42 45 39 37 39 72 108 60 81 49 42 41 59 145 75 48 47 38 35 35 32 30 31 35 APRIL 54 91 104 101 99 95 78 59 46 39 39 78 100 74 88 93 99 101 105 201 151 113 109 105 101 99 96 92 85 75 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MEAN DISCHARGE (CFS) MAY 8.0 13 11 9.8 9.3 8.4 8.4 7.2 4.8 3.9 4.2 17 30 12 19 12 12 11 17 87 33 15 14 10 9.3 9.4 8.1 7.1 7.2 6.8 42 174 60 41 35 64 117 62 47 41 40 64 49 39 71 1090 214 106 74 146 101 63 1400 2020 333 2740 399 202 144 249 146 69 160 94 79 71 86 137 110 91 72 61 69 79 74 65 2190 998 82 70 170 298 240 834 695 101 1420 246 80 40 168 93 8.3 88 16 9.0 6.7 22 47 18 12 8.2 6.8 12 11 7.6 13 15200 761 25 14 148 88 41 8620 7420 112 21400 293 49 16 235 41 521 479 177 922 265 196 184 207 221 436 442 1070 689 522 264 263 400 259 169 147 1020 234 179 144 127 116 113 110 97 93 —— MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) JUNE 521 479 177 922 265 196 184 207 221 436 442 1070 689 522 264 263 400 259 169 147 1020 234 179 144 127 116 113 110 97 93 349 788 122 665 40 40 82 131 169 361 348 961 570 421 114 183 406 348 170 117 1470 108 58 50 52 69 80 111 136 168 1790 1430 63 3830 29 21 45 83 104 566 465 4290 1220 644 87 141 608 243 81 47 6150 75 27 19 17 21 24 33 36 41 TOTAL 1513 424.9 10373 54748.6 10066 22230 RIO GRAMDB DB LOIZA BASIN 50055000 RIO QRAKDB DB LOIZA AT CAGOAS, PR—Continued SBDIMBHT DISCHARGE, SOSPBNDBD (TONS/DAY), WATER YBAR OCTOBER 1991 TO SEPTEMBER 1992 261 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL YBAR MBAN DISCHARGE (CPS) 89 81 78 77 146 84 74 84 98 77 141 108 76 69 76 82 222 100 93 146 106 364 118 89 171 105 82 75 66 62 66 3305 80650 MBAN CONCBN- SBDIMBNT TRATION DISCHARGB (MQ/L) (TONS/DAY) JULY 203 190 137 87 118 61 39 48 46 24 108 95 55 56 89 170 231 92 87 112 93 386 266 145 143 75 33 23 21 25 27 47 41 28 18 51 15 7.8 13 13 4.9 58 31 12 10 19 38 179 25 22 45 27 598 89 36 86 24 7.3 4.6 3.7 4.1 4.6 1562.0 : 4-3596.2 MBAN MBAN CONCBN- SEDIMENT DISCHARGB TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AOGOST 66 66 76 63 1610 644 233 159 123 243 150 171 122 130 161 111 104 99 91 91 88 80 81 113 85 73 89 77 85 73 95 23 21 19 19 1520 917 213 130 100 317 iao 183 56 100 140 76 43 19 15 17 19 20 20 84 66 62 66 53 68 61 77 4.0 3.8 4.0 3.3 11800 2280 148 58 34 235 54 92 19 44 67 23 12 5.2 3.7 4.1 «•* I.I 4.4 28 IS ft 1* ii 16 12 21 MBAN MBAN CONCBN- SBDIMBNT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) SEPTEMBER 87 72 104 93 80 89 89 73 280 103 78 70 63 61 60 99 284 165 746 2870 1660 335 207 161 135 121 113 1*3 10) 102 40 46 84 80 67 74 72 64 274 65 50 58 54 51 53 117 247 131 661 1450 1310 338 286 166 83 33 13 18 24 33 10 9.0 25 21 15 19 17 13 267 20 10 11 9.4 8.3 8.6 36 262 60 2490 28400 9040 304 167 76 30 11 3.9 4.9 6.7 8.8 5452 15039.4 8605 41363.6 262 RIO QRANDB DE LOIZA BASIN 50055000 RIO GRANDS DB LOIZA AT CAOUAS, PR—Continued WATER QUALITY DATA, WATER YBAR OCTOBER 1991 TO SEPTEMBER 1992 PARTICLE-SIZE DISTRIBUTION OP SUSPENDED SEDIMENT DATE NOV 1991 07. .. 08. .. 24... JAN 1992 05. .. MAY 16... 23... 26... DATE NOV 1991 07. .. 08. .. 24. .. JAN 1992 05. .. MAY 16... 23... 26. .. TIME 0923 1000 1358 2039 1355 2313 0337 SBD. SUSP. PALL DIAM. PERCENT FINER THAN .016 MM 70 50 35 55 21 -- 54 DIS- CHARGE, INST. CUBIC FEET PER SECOND 3460 3210 1260 40600 1580 9720 14400 SBD. SUSP. PALL DIAM. PERCENT FINER THAN .031 MM 77 64 51 70 34 60 63 SEDI- MENT, SUS- PENDED (MQ/L) 3010 4310 18500 9250 17500 3150 4800 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 98 88 71 80 42 93 91 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 28100 37300 62800 1010000 74800 82700 186000 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 99.2 95 90 88 65 $8.6 97 SBD. SUSP. PALL DIAM. PERCENT FINER THAN .002 MM 29 16 4 21 5 33 27 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 99.6 99.4 97 93 8? 99.5 99 SBD. SUSP. PALL DIAM. PERCENT FINER THAN .004 MM 38 25 15 30 9 41 33 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 99.8 99.8 98 98 96 99.8 99.7 SBD. SUSP. PALL DIAM. PERCENT FINER THAN .008 MM 50 36 23 39 14 47 43 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 99.9 99.9 99 99 99 too 99.8 L6 E6 86 66 S6 66 66 C6 96 tL S6 tL 86 96 S8 96 L6 96 96 96 »6 66 L6 96 L9 E6 S6 86 »6 Ml C90* HYHJ, H8NI* •LNSOHHd •HYId 8A3I8 •dSQS •aas OSS9 0989 8»I C»S Oi>8 E6 98 OOT9I 00988 OOS9 QS9L OLLL 06t1 OOECOT OOOiT C8 OOECC 00089T 1L t'L OOOC8* OOTTS OTOC 09SC 00t6t OOECE OttL 09 ES 009CC (AVG/1) aaaNad -80S 'aOMYHO -sia 'Juan -iaas E69T OOOT 88C EE9 090C Let TEC OS8E 090E OE9T 0061 080C 16V OCOE OP8E L0£ 0099 09t6 t91 9S DECS OOSL E6S LOS 09S9 09tt 09ET OCCT 0>E9 (a/on) aaoNad -80S 'iNan -iaas EE»T LtSit T6T Lit OCST OCT 8ET OPST OS»E 08»T OEST 08ET OSOT 009CT CP9T 66 008T OCA9 C9T OS OOT»E OCSC OSCT QL91 OLtt OL9t ooot Ot91 OCET (sao) SQOaNVi -MVXSHI 'MO-M -HYaiLLS 9t1t 1V81 OOTT 0080 SE60 ET80 OT90 £EOT CT80 £090 CTOO csot tttl tvtt ttot 9060 S08T SVV1 0060 8011 9t61 »S9T ESST SSCI 0»TT SS80 OC90 ECET EE&O anii ••'6T ' "6T •"6T •••OT ' "SO OQV * * ' tt •••ot anr • "it • ' 'it •••it •••to • "10 NOT '"9t '"tt '"tt •"It '"91 '"91 AYR '"It MdY ' "EO HYM •••so •••so C66T NYC "'9t '"90 '"90 '"90 '"90 •"LO •"LO 1661 AOK SiYQ £9? aaoNadsos ao iNaoaad AVID ONY ms C66i majoidas ox i66i aaaoxoo HYHA HBXYM 'viva AIIIYOD HSIVM P»ntiT^tioo--gYQOYO iV YZIOa SO aOHVHO OIH OOOSSOOS msva Yzion aa aaMvuo om 264 RIO GRANDB OB LOIZA BASIN 50055100 RIO CAGOITAS NEAR AGOAS BDBNAS, PR LOCATION.--Lat 18°14'48", long 660 OS'37", Hydrologic Unit 21010005, on right bank 450 ft (137 m) upstream from bridge on Highway 777, 1.0 mi (1.6 km) southeast from Aguas Buenas, 3.9 mi (6.3 km) northwest from Caguas, and 2.1 mi (3.4 km) southwest from Las Carolinas. DRAINAGE AREA.--5.30 mi* (13.72 km*). WATER-DISCHARGE RECORDS PERIOD OP RECORD.--February 1990 to current year. GAGB.--Water-stage recorder and crest-stage gage. Elevation of gage is 394 ft (120 m), from topographic map. REMARKS.--Records fair except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. DAY DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES OCT NOV DEC JAN FBB MAR APR MAY JUN JUL e Estimated STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1990 - 1992, BY WATER YEAR (WY) MEAN MAX (WY) MIN (WY) 13.1 20.9 1991 5.30 1992 6.61 7.46 1992 S.76 1991 7.44 9.28 1991 S.S9 1992 12.0 16.7 1992 7.19 1991 5.24 8.00 1991 3.51 1990 6.29 8.87 1990 3.60 1992 4.17 5.64 1991 3.19 1992 4.56 6.41 1992 2.48 1990 3.79 4.06 1992 3.40 1991 5.21 7.29 1991 3.74 1990 AUG 5.68 6.28 1992 5.14 1991 SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN AC -FT CFSM IN. 6.7 11 6.6 5.2 5.6 5.0 5.5 5.3 4.8 4.8 4.7 4.6 4.5 4.5 4.7 4.4 4.4 4.2 4.3 4.2 4.1 9.9 S.O 4.4 4.1 4.1 4.1 4.1 4.1 10 5.3 164.2 5.30 11 4.1 326 1.00 1.15 5.2 5.3 4.4 4.4 5.2 5.6 16 42 15 7.3 6.0 5.5 5.3 5.1 4.9 .9 .9 .7 .7 .8 9.7 10 5.6 6.4 5.3 5.0 5.3 5.0 4.9 5.4 --- 223.8 7.46 42 4.4 444 1.41 1.57 5.1 4.9 5.0 4.8 7.4 4.9 9.4 4.9 6.2 235 5.6 116 5.3 14 5.1 7.8 5.0 7.1 5.0 9.2 4.9 6.0 5.1 5.4 5.4 5.4 6.5 5.0 5.0 4.8 5.0 11 5.0 8.7 4.9 5.3 4.8 .8 8.7 .7 7.7 .6 5.6 .6 5.3 .5 5.2 .5 5.1 .6 S.O .6 S.O .4 S.O .4 .1 .1 .3 .3 .3 .3 .2 .2 .3 • 4 .5 .3 .3 .3 .2 .4 .3 .3 .3 .1 .0 .1 .1 .2 .2 .1 .0 .0 S.O .4 3.8 S.O .4 S.O .1 173.3 518.8 123.0 S.S9 16.7 4.24 9.4 235 5.4 4.8 4.1 3.8 344 1030 244 1.05 3.16 .80 1.22 3.64 .86 3.8 3.8 3.8 3.7 3.6 3.6 3.6 3.5 3.4 3.5 3.5 3.3 3.3 3.4 3.6 3.3 4.3 3.7 3.5 3.4 3.2 3.3 3.1 2.9 2.9 2.9 2.9 9.1 3.7 3.1 2.9 111.6 3.60 9.1 2.9 221 .68 .78 2.9 3.0 3.0 2.9 2.9 3.0 3.4 3.1 2.9 2.8 2.9 3.1 2.8 2.7 2.7 2.7 2.9 2.9 11 5.1 3.1 3.0 2.8 2.7 2.6 2.6 2.6 2.6 2.5 2.6 --- 95.8 3.19 11 2.5 190 .60 .67 3.0 3.6 2.8 2.6 2.6 2.9 2.9 2.6 2.5 2.4 2.5 3.5 3.1 2.7 2.7 3.6 5.1 3.7 4.6 5.1 7.4 S.O 36 34 18 9.6 6.S 5.2 4.7 4.5 4.3 199.7 6.44 36 2.4 396 1.22 1.40 4.1 4.1 4.0 4.3 3.9 3.7 4.7 4.4 3.9 4.3 4.4 6.2 S.6 4.4 4.0 4.4 4.0 3.8 3.7 3.6 5.0 3.7 3.5 3.4 3.4 3.3 3.4 3.6 3.6 3.3 —— 121.7 4.06 6.2 3.3 241 .77 .85 3.4 3.3 3.4 3.4 3.9 3.4 3.4 4.0 •3.6 3.4 4.2 3.3 e3.1 e3.1 e3.5 eS.O e7.0 e4.5 e3.8 e3.6 eS.O e7.0 e4.3 eS.O e6.2 e4.8 e4.8 e3.4 3.0 3.1 3.1 126.0 4.06 7.0 3.0 250 .77 .88 3.2 3.4 3.8 6.1 77 13 5.7 4.5 4.0 3.6 3.7 3.8 3.5 3.6 3.4 3.2 3.1 3.0 2.9 2.9 2.9 2.9 3.0 3.1 3.0 3.0 3.5 3.2 3.4 3.9 4.3 193.6 6.25 77 2.9 384 1.18 1.36 3.3 3.2 e3.9 e3.5 e6.3 e4.4 e3.9 e3.9 e7.6 •3.5 3.4 3.2 3.1 4.0 3.6 6.1 4.1 4.6 41 31 14 19 ell e6.4 5.3 .9 .7 .6 .5 .8 226.8 7.56 41 3.1 450 1.43 1.59 6.01 7.95 1992 5.01 1991 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS SO PERCENT EXCEEDS FOR 1991 CALENDAR YEAR 2161.0 5.92 82 Jul 16 2.8 Jun 18 2.8 Jun 16 4290 1.12 15.17 7.4 5.2 FOR 1992 WATER YEAR WATER YEARS 1990 - 1992 2278.3 6.22 235 2.4 2.6 1850 21.20 2.4 4S20 1.17 15.99 7.0 4.3 Jan 5 May 10 Apr 24 Aug S Aug 5 May 9 6 7 6 23S 1 1 1460 IS 1 4970 1 17 7 4 .86 .42 .30 .8 .9 .24 .8 .29 .59 .8 .4 Jan May May Oct Oct May 5 7 22 15 IS 3 1991 1992 1992 1990 1990 1990 1990 1990 RIO GRANDB DB LOIZA BASIN 50055100 RIO CAGUITAS NEAR AQUAS BUBNAS, PR—Continued WATER-QUALITY RECORDS PERIOD OF RECORDS.— Water years 1990 to current year. INSTRUMENTATION.-- DH-48 and automatic sediment sampler. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: February 1990 to September 1992 EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATION: Maximum daily mean, 1,370 mg/L Jan. 05, 1992; Minimum daily 2 m0/L Several days. 265 in, SEDIMENT LOADSi Maximum daily mean, 3,730 tons (3,360 tonnes) Jan. 05, 1992; Minimum daily mean, 0.02 ton (0.03 tonne) Several days. EXTREMES FOR WATER YEARS 1990-92.-- Water Year 1990 1991 1992 Suspended-sediment concentration (mg/L) maximum minimum Suspended-sediment discharge (tons per day) maximum minimum 326 (Sep. 03) 782 (Jul. 16) 1,370 (Jan. 05) 4 (May, 18) 2 (Nov. 4-5) 2 (Several days) 297 (Jul. 13) 1.020 (Oct. 15) 3,730 (Jan. 05) .02 (May, 18) .04 (Nov. 4-5) .02 (Several days) SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1989 TO SEPTEMBER 1990 DAY MEAN DISCHARGE (CFS) MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) JANUARY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) FEBRUARY e3.6 e4.2 e4.0 e3.4 e3.0 e2.7 e2.6 e3.0 e3.5 eS.O e4.0 e3.6 2.9 4.8 3.2 3.0 3.4 3.7 3.4 3.1 3.7 4.3 3.7 3.7 3.4 3.4 3.0 3.0 13 19 16 12 11 19 13 11 13 15 12 12 14 16 16 14 12 13 12 11 e5.0 e.26 e.18 e.12 .08 .29 .11 .08 .12 .16 .12 .10 .14 .18 .17 .14 .12 .12 .10 .08 98.3 MEAN DISCHARGE (CFS) 3.7 3.3 3.0 3.0 2.9 2.9 2.9 2.8 13 6.3 5.3 19 39 50 13 16 12 8.0 6.5 5.9 5.3 5.1 5.2 .8 .6 .5 .4 .4 .7 .9 .5 270.9 MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) MARCH 13 12 11 11 11 11 11 10 62 27 22 88 201 258 55 76 55 34 26 23 20 19 19 18 17 17 17 19 19 19 18 .13 .10 .08 .08 .08 .08 .08 .08 4.3 .52 .36 5.5 24 54 2.1 5.1 2.0 .75 .45 .34 .28 .26 .26 .24 .22 .22 .23 .22 .24 .26 .23 102.79 e Estimated 266 RIO QRANDB DB LOIZA BASIN 50055100 RIO CAGOITAS NEAR AGOAS BUBNAS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1989 TO SEPTEMBER 1990 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 IS 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 4.2 3.9 3.9 3.7 3.7 3.6 3.6 3.5 3.8 3.9 3.4 3.2 5.5 4.2 3.6 3.4 3.2 3.0 4.6 3.8 3.0 2.5 2.3 2.1 9.7 5.4 2.8 2.4 2.1 2.1 __. APRIL 17 16 15 14 14 14 14 14 14 15 13 13 22 16 12 11 11 11 17 13 11 10 8 7 44 22 10 8 7 7 ___ .19 .17 .15 .14 .14 .14 .14 .13 .15 .17 .12 .11 .45 .19 .11 .10 .10 .09 .24 .14 .09 .07 .05 .04 4.4 .42 .07 .05 .04 .04 ___ MAY 2.1 2.1 2.0 2.0 2.0 1.9 1.8 1.8 6.6 4.9 4.0 2.7 2.8 3.0 2.7 2.5 2.1 2.1 2.1 2.0 1.9 1.8 1.8 1.9 2.0 2.0 2.0 2.1 2.1 2.2 2.9 7 7 7 7 7 7 7 7 30 17 11 10 11 11 10 8 7 4 7 7 7 7 7 7 7 7 7 7 7 7 8 .04 .04 .04 .04 .04 .04 .04 .04 1.3 .21 .12 .08 .09 .09 .08 .06 .04 .02 .04 .04 .04 .04 .04 .04 .04 .04 .04 .04 .04 .04 .07 MEAN DISCHARGE (CFS) 2.7 2.9 2.8 2.8 3.1 2.9 4.1 3.4 2.8 2.3 2.3 2.3 2.3 4.2 12 6.0 .8 .4 .3 .1 .1 .1 9.0 6.2 7.1 5.5 4.7 4.5 4.4 4.1 MEAN CONCEN- TRATION (MG/L) JUNE 9 9 9 10 11 10 16 11 8 7 7 7 7 39 52 23 17 15 14 13 13 13 38 23 19 18 15 14 13 13 SEDIMENT DISCHARGE (TONS/DAY) .06 .08 .06 .07 .09 .07 .26 .11 .07 .04 .04 .04 .04 .43 1.8 .37 .21 .17 .16 .14 .14 .14 1.6 .37 .36 .26 .19 .17 .16 .14 TOTAL 110.1 8.44 75.9 2.96 130.2 7.84 DAY RIO GRANGE DB LOIZA BASIN 50055100 RIO CAGUITAS NEAR AGDAS BUENAS, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1989 TO SEPTEMBER 1990 267 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL 4.1 4.0 3.9 3.9 3.2 6.1 4.0 3.7 3.4 3.2 3.2 3.2 3.7 3.7 11 4.0 6.9 5.3 3.6 3.1 2.6 2.5 2.3 4.1 3.9 2.8 2.5 2.2 2.3 2.5 2.6 117.5 JULY 14 7 11 11 11 23 15 12 11 11 11 11 14 14 50 17 29 21 13 11 10 8 7 28 82 45 39 36 33 28 23 .15 .08 .12 .12 .10 .45 .16 .11 .10 .10 .10 .10 .14 .14 5.0 .19 .88 .36 .12 .09 .07 .05 .04 .83 1.0 .34 .25 .21 .20 .18 .16 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AUGUST 11.94 3.1 18 7.1 4.4 5.4 4.1 4.4 4.6 3.6 4.3 3.8 3.6 44 10 4.6 3.9 3.7 3.9 3.2 2.9 2.9 3.1 3.3 3.0 3.4 3.4 2.9 2.9 2.9 2.8 2.7 175.9 20 85 27 15 34 41 40 37 34 31 28 23 270 55 40 38 33 30 34 39 40 35 25 15 10 10 10 10 10 10 7 .17 9.0 .57 .18 .68 .44 .46 .46 .33 .36 .28 .21 297 1.8 .50 .39 .35 .32 .29 .31 .32 .30 .22 .12 .10 .09 .08 .08 .08 .08 .06 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) 315.63 2.7 4.7 37 10 4.7 4.6 4.2 3.9 3.6 «3.5 3.0 3.0 3.3 3.4 4.4 3.7 3.6 3.5 3.4 3.2 6.0 4.6 3.8 3.5 3.5 3.8 3.4 3.2 4.5 152.8 SEPTEMBER 6 17 326 238 40 .05 .34 98 9.2 .51 40 38 37 24 15 11 11 12 11 11 14 18 17 14 11 10 24 19 17 14 12 11 11 10 18 .50 .46 .38 .23 e.14 e.09 .08 .09 .10 .10 .19 .17 .15 .13 .10 .08 .78 .24 .18 .12 .10 .12 .09 .08 .37 113.17 e Estimated 263 RI° GRANDB DB LOIZA BASIN 50055100 RIO CAGUITAS NEAR AGDAS BOBNAS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) OCTOBER 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 3.8 3.3 3.8 4.1 3.6 3.6 11 4.2 3.5 11 5.8 4.2 5.5 6.6 100 30 13 77 32 36 109 19 11 17 25 47 20 12 9.5 8.5 7.6 12 12 13 15 14 14 74 83 80 103 110 110 94 78 590 200 59 424 151 225 597 88 51 77 118 240 79 35 30 28 23 .15 .11 .15 .16 .13 .13 8.9 .99 .82 4.7 1.8 1.3 1.5 1.3 1020 24 2.4 212 21 76 278 5.0 1.7 8.0 11 45 5.2 1.1 .76 .63 .48 NOVEMBER 7.3 7.0 6.7 6.5 6.1 6.0 5.9 5.8 5.5 5.4 5.2 5.2 5.1 5.0 5.1 6.8 5.4 5.3 5.2 6.2 5.4 5.6 5.3 5.0 4.9 7.1 6.4 5.4 5.0 6.1 16 8 3 2 2 4 5 5 4 5 6 6 7 9 8 23 12 8 8 17 16 13 9 6 5 17 29 22 20 29 .32 .17 .07 .04 .04 .06 .08 .08 .07 .07 .08 .08 .10 .12 .12 .51 .17 .12 .11 .42 .24 .19 .14 .09 .06 .35 .61 .32 .28 .59 MEAN DISCHARGE (CFS) 9.5 7.4 29 9.7 6.2 5.4 5.1 .9 .9 .7 .6 .4 .5 5.0 6.2 5.2 .7 .6 .5 .4 .4 .5 .6 .6 .4 4.4 6.1 5.4 9.5 12 93 MEAN CONCEN- TRATION (MG/L) DECEMBER 38 32 152 42 24 20 20 19 25 26 16 10 10 20 27 23 20 25 37 47 48 43 38 30 19 9 18 22 42 55 499 SEDIMENT DISCHARGE (TONS/DAY) 1.3 .83 19 1.3 .40 .29 .26 .24 .32 .34 .20 .12 .12 .26 .46 .34 .25 .30 .44 .56 .57 .52 .47 .37 .22 .11 .43 .35 1.9 2.4 186 TOTAL 647.6 1734.41 172.9 5.70 287.8 220.67 269 RIO GRANDS DE LOIZA BASIN 50055100 RIO CAGUITAS NEAR AQUAS BUBNAS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) JANUARY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 10 7.8 6.8 7.4 10 7.2 6.8 7.3 8.6 7.4 6.7 6.3 5.9 5.9 5.8 5.7 5.7 5.7 5.6 5.5 5.5 5.3 5.3 5.2 5.2 5.2 5.2 5.2 5.2 5.5 148 22 18 18 28 48 29 25 25 25 28 32 27 16 11 11 12 11 9 8 7 6 5 4 6 8 8 9 15 25 30 18 .63 .38 .33 .67 2.0 .58 .44 .50 .65 .54 .56 .45 .25 .17 .17 .17 .16 .14 .12 .10 .08 .08 .07 .09 .12 .12 .13 .21 .35 .47 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) FEBRUARY 5.7 5.6 5.6 5.3 41 14 7.7 6.0 5.5 5.3 5.8 15 9.8 6.6 6.1 5.8 5.7 6.3 8.2 6.4 6.1 6.0 5.9 5.9 5.8 5.7 5.6 5.7 ___ -__ ___ 30 29 24 16 209 67 59 40 25 20 20 74 59 33 24 21 20 23 56 52 48 43 36 29 20 12 7 8 --_ ___ ___ .48 .43 .35 .22 117 3.4 1.2 .66 .37 .28 .29 8.6 1.8 .61 .39 .32 .30 .42 1.3 .92 .85 .69 .57 .45 .31 .18 .12 .13 ___ ___ ___ MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MARCH 5.6 5.5 5.5 5.8 6.0 6.1 5.8 6.0 5.8 5.4 5.5 5.5 5.5 5.5 5.5 5.7 5.7 6.2 6.3 5.9 5.8 23 8.2 6.7 6.1 5.8 5.7 5.6 5.5 5.5 5.4 18 29 37 43 39 29 21 13 10 8 8 10 12 14 14 14 14 17 40 30 18 213 46 20 18 13 10 14 17 17 16 .27 .43 .55 .67 .62 .46 .32 .20 .15 .12 .12 .14 .17 .20 .21 .22 .22 .28 .71 .49 .27 23 1.3 .36 .30 .20 .15 .21 .26 .26 .23 TOTAL 222.9 28.73 224.1 142.64 198.1 33.09 270 RIO GRANDS OB LOIZA BASIN 50055100 RIO CAGUITAS NEAR AG0AS BUBNAS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL 5.4 5.5 5.5 5.5 5.2 5.2 5.2 6.6 5.8 5.6 5.8 6.3 7.2 5.9 5.8 5.9 5.6 5.5 5.5 5.5 5.5 5.4 5.3 5.3 5.3 5.7 5.3 5.3 5.5 6.1 --- 169.2 APRIL 12 9 8 7 6 6 7 9 7 6 8 10 10 10 10 10 10 10 8 6 5 5 6 8 10 10 10 12 14 17 ___ MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MAY .17 .13 .12 .10 .08 .08 .10 .16 .11 .09 .13 .18 .20 .16 .16 .16 .15 .14 .13 .10 .08 .08 .08 .11 .14 .15 .14 .17 .21 .27 --- 4.08 7.7 7.5 6.2 5.8 5.7 5.7 7.3 7.0 4.1 4.4 4.3 4.4 3.6 3.5 3.4 3.4 3.4 3.9 6.5 4.1 3.7 3.6 3.4 3.3 11 4.1 3.7 3.5 3.3 3.3 3.3 148.1 24 30 24 23 21 21 27 31 17 86 106 85 61 38 32 28 23 18 28 17 16 24 21 20 52 24 22 22 20 13 14 .50 .60 .40 .35 .32 .32 .57 .67 .21 1.1 1.3 .95 .60 .35 .29 .26 .22 .21 .84 .20 .18 .23 .19 .18 3.1 .29 .23 .21 .18 .12 .13 15.30 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) JUNE 3.3 3.2 3.2 3.2 3.2 3.6 3.3 3.2 3.1 3.0 3.0 3.1 3.1 3.0 2.9 2.9 2.9 2.8 2.8 2.8 2.8 2.8 4.0 3.5 3.3 3.2 3.3 3.2 3.3 11— - 102.0 15 15 15 14 12 11 11 10 8 9 10 10 7 6 9 8 7 10 11 11 8 6 16 19 16 13 11 11 11 47 — - .14 .13 .12 .11 .10 .11 .10 .08 .06 .07 .08 .08 .06 .05 .07 .07 .06 .07 .08 .08 .06 .04 .21 .18 .14 .11 .10 .10 .10 5.7 8.46 RIO GRANDK DE LOIZA BASIN 50055100 RIO CAGUITAS NEAR AGUAS BUBNAS, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 271 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) 1 2 3 4 S 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL YEAR 13 4.2 3.4 3.5 3.3 3.3 3.8 5.2 4.1 3.3 3.3 3.4 3.3 3.4 9.7 82 8.1 6.2 5.7 5.3 .9 .7 .6 .8 .5 .1 .1 .2 .2 .2 .1 225.9 2708.0 JULY 64 26 21 21 20 20 34 25 20 20 19 16 14 13 45 782 183 43 26 20 15 10 10 11 12 12 12 11 11 9 7 --- 6.0 .30 .20 .19 .18 .18 .47 .58 .22 .18 .17 .14 .12 .12 4.2 477 4.5 .74 .42 .30 .19 .13 .12 .13 . 14 .14 .13 .12 .12 .11 .08 497.62 2725.26 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AUGUST .2 .0 .0 .1 .1 .3 .3 .3 .2 .4 .3 .4 .3 .4 .4 .7 .9 .0 .8 .8 5.2 8.3 5.5 4.7 4.4 4.2 18 7.2 5.0 4.5 4.3 159.2 6 7 8 8 9 9 8 7 6 8 11 14 15 15 15 15 16 16 14 11 10 36 44 32 29 23 82 26 13 13 13 .06 .07 .08 .09 .10 .10 .10 .08 .07 .10 .13 .16 .18 .18 .18 .19 .23 .23 .18 .15 .14 1.4 .65 .40 .34 .25 12 .62 .17 .16 .15 SEPTEMBER 18.94 4.1 4.2 4.1 4.1 4.0 3.8 3.9 4.1 4.3 4.3 4.2 4.1 4.1 4.1 3.9 3.9 17 5.4 5.5 4.5 4.3 5.2 6.7 4.7 4.2 4.1 5.1 4.9 7.1 6.3 150.2 12 11 10 9 9 10 10 10 8 8 8 8 8 8 8 8 73 22 60 18 16 16 38 28 17 13 18 22 22 26 .13 .12 .12 .10 .09 .10 .11 .10 .09 .08 .08 .08 .08 .08 .08 .08 9.2 .35 .88 .22 .19 .24 .75 .38 .20 .14 .33 .29 .44 .49 15.62 272 RIO GRANDS DB LOIZA BASIN 50055100 RIO CAGOITAS NEAR AGOAS BDBNAS, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CPS) (MG/L) (TONS/DAY) OCTOBER 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 6.7 11 6.6 5.2 5.6 5.0 5.5 5.3 4.8 4.8 4.7 4.6 4.5 4.5 4.7 4.4 4.4 4.2 4.3 4.2 4.1 9.9 5.0 4.4 4.1 4.1 4.1 4.1 4.1 10 5.3 38 106 33 22 15 12 21 42 36 30 24 20 19 15 12 12 12 12 12 12 12 98 13 11 10 10 10 10 9 94 21 .75 5.5 .58 .31 .20 .16 .47 .62 .48 .40 .31 .24 .22 .19 .15 .14 .14 .14 .14 .14 .14 15 .19 .13 .12 .12 .12 .11 .10 8.2 .32 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) NOVEMBER 5.2 5.3 4.4 4.4 5.2 5.6 16 42 15 7.3 6.0 5.5 5.3 5.1 4.9 .9 .9 .7 .7 .8 9.7 10 5.6 6.4 5.3 5.0 5.3 5.0 4.9 5.4 18 18 17 16 16 26 559 724 142 46 33 27 22 20 19 15 12 12 12 11 95 70 35 34 19 22 58 100 119 129 .25 .26 .21 .19 .22 .39 34 111 8.3 .98 .53 .40 .31 .27 .25 .20 .16 .16 .15 .14 9.0 2.3 .53 .72 .27 .29 .77 1.3 1.6 1.8 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) 5.1 5.0 7.4 9.4 6.2 5.6 5.3 5.1 5.0 5.0 4.9 5.1 5.4 6.5 5.0 5.0 5.0 4.9 4.8 8.7 7.7 5.6 5.3 5.2 5.1 5.0 5.0 5.0 5.0 5.0 5.0 DECEMBER 135 127 126 113 48 1.9 1.7 2.5 3.0 .86 16 11 8 8 8 8 8 12 27 8 8 8 8 8 60 44 12 10 16 29 34 24 13 8 8 8 .24 .15 .11 .10 .10 .10 .10 .21 .58 .11 .10 .10 .10 .10 2.8 1.1 .18 .13 .22 .39 .45 .32 .17 .11 .10 .10 TOTAL 164.2 35.83 223.8 176.95 173.3 18.23 RIO GRAMDB DB LOIZA BASIN 273 50055100 RIO CAGUITAS NEAR AQUAS BUBNAS, PR--Continued SBDIMBNT DISCHARGE, SUSPENDED (TONS/DAY), WATER YBAR OCTOBER 1991 TO SEPTEMBER 1992 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CFS) 4.9 4.8 4.9 4.9 235 116 14 7.8 7.1 9.2 6.0 5.4 5.4 5.0 4.8 11 8.7 5.3 .8 .7 .6 .6 .5 .5 .6 .6 .4 .4 .4 .4 .1 MEAN CONCEN- TRATION (MQ/L) JANUARY 8 8 8 8 1370 1340 104 26 22 62 11 11 11 11 11 123 60 82 12 12 10 6 5 S 5 5 5 5 5 5 5 SEDIMENT MBA1 DISCHARGE DISCHA1 (TONS/DAY) (CFS .10 .10 .10 .10 3730 566 4.9 .57 .48 2.1 .17 .15 .15 .14 .14 17 2.6 1.2 .15 .14 .12 .08 .06 .06 .06 .06 .06 .06 .06 .06 .06 1 1GB .1 .1 .3 .3 .3 .3 .2 .2 .3 •« .5 .3 .3 .3 .2 .4 .3 .3 .3 .1 .0 .1 .1 .2 .2 .1 .0 .0 3.8 .__ MEAN CONCEN- TRATION (MG/L) FEBRUARY 5 6 8 10 9 7 5 7 10 10 10 9 8 6 6 8 9 13 18 20 19 15 10 8 8 8 8 B 7 __- ___ SBDIMBNT DISCHARGE (TONS/DAY) .06 .08 .10 .11 .10 .07 .06 .08 .11 .13 .11 .10 .09 .07 .07 .08 .11 .15 .21 .22 .21 .16 .10 .08 .09 .09 .08 .08 .07 _-- MEAN DISCHARGE (CFS) 3.8 3.8 3.8 3.7 3.6 3.6 3.6 3.5 3.4 3.5 3.5 3.3 3.3 3.4 3.6 3.3 4.3 3.7 3.5 3.4 3.2 3.3 3.1 2.9 2.9 2.9 2.9 9.1 3.7 3.1 2.9 MEAN CONCEN- TRATION (MG/L) MARCH 6 5 4 3 3 4 6 7 8 8 7 6 6 5 4 4 5 5 5 6 7 6 4 3 6 9 10 91 20 16 12 SBDIMBNT DISCHARGE (TONS/DAY) .05 .04 .03 .02 .02 .04 .06 .07 .08 .08 .07 .06 .06 .05 .04 .04 .05 .05 .04 .05 .06 .05 .03 .02 .04 .06 .08 11 .22 .12 .09 TOTAL 518.8 4327.03 123.0 3.07 111.6 12.77 274 RIO GRANDE DB LOIZA BASIN 50055100 RIO CAGUITAS NEAR AGDAS BUBNAS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MAY MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 2.9 3.0 3.0 2.9 2.9 3.0 3.4 3.1 2.9 2.8 2.9 3.1 2.8 2.7 2.7 2.7 2.9 2.9 11 5.1 3.1 3.0 2.8 2.7 2.6 2.6 2.6 2.6 2.5 2.6 ___ APRIL 10 8 6 4 4 7 12 13 11 9 6 5 4 2 2 2 3 5 117 40 23 21 20 16 12 13 13 12 10 10 ___ .07 .06 .05 .04 .04 .07 .11 .11 .09 .07 .05 .04 .03 .02 .02 .02 .03 .04 19 .80 .19 .17 .15 .11 .08 .09 .10 .08 .06 .07 ___ 3.0 3.6 2.8 2.6 2.6 2.9 2.9 2.6 2.5 2.4 2.5 3.5 3.1 2.7 2.7 3.6 5.1 3.7 4.6 5.1 7.4 5.0 36 34 18 9.6 6.5 5.2 4.7 4.5 4.3 10 7 5 3 3 2 2 2 2 2 2 13 37 33 25 21 36 15 25 32 63 26 420 468 227 75 31 19 16 14 12 .08 .08 .03 .02 .02 .02 .02 .02 .02 .02 .02 .34 .34 .25 .20 .22 1.7 .17 .46 .83 3.7 .40 167 97 31 2.3 .56 .26 .20 .16 .14 MEAN DISCHARGE (CPS) 4.1 4.1 4.0 4.3 3.9 3.7 4.7 4.4 3.9 4.3 4.4 6.2 5.6 4.4 4.0 4.4 4.0 3.8 3.7 3.6 5.0 3.7 3.5 3.4 3.4 3.3 3.4 3.6 3.6 3.3 MEAN CONCEN- TRATION (MG/L) JUNE 12 12 12 11 11 9 18 37 29 25 21 128 31 18 16 15 13 12 12 12 27 24 20 15 10 11 16 19 17 13 SEDIMENT DISCHARGE (TONS/ DAY) .14 .13 .12 .14 .11 .09 .35 .46 .32 .30 .26 2.5 .53 .22 .18 .17 .14 .12 .12 .12 .46 .24 .18 .13 .09 .09 .15 .18 .16 .11 95.8 21.86 199.7 307.58 121.7 8.31 RIO GRANDS DB LOIZA BASIN 50055100 RIO CAGUITAS NEAR AGUAS BUBNAS, PR- -Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 275 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CPS) (MG/L) (TONS/ DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL YEAR e B«ti 3.4 3.3 3.4 3.4 3.9 3.4 3.4 4.0 •3.6 3.4 4.2 3.3 e3.1 e3.1 e3.5 eS.O e7.0 e4.5 e3.8 e3.6 eS.O e7.0 e4.3 eS.O e6.2 e4.8 e4.8 e3.4 3.0 3.1 3.1 126.0 2278.3 Bated JULY 8 .08 8 .07 10 .09 10 .10 10 .10 10 .10 10 .10 10 .10 8 .09 9 .09 19 .22 35 .31 45 e.38 41 27 20 19 17 15 13 11 15 19 17 13 10 7 5 .34 .25 .26 .36 .20 .16 .12 .14 .28 .21 .22 .22 .13 .09 .04 5 .04 5 .04 6 .06 —— 4.99 5994.27 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) AUGUST 3.2 3.4 3.8 6.1 77 13 5.7 4.5 4.0 3.6 3.7 3.8 3.5 3.6 3.4 3.2 3.1 3.0 2.9 2.9 2.9 2.9 3.0 3.1 3.0 3.0 3.5 3.2 3.4 3.9 4.3 193.6 8 9 10 36 712 186 68 36 36 33 25 15 7 4 5 5 5 5 6 6 4 4 7 10 11 10 12 12 11 11 11 —— .07 .08 .10 1.2 621 11 1.1 .44 .37 .32 .25 .15 .07 .04 .04 .04 .04 .04 .04 .04 .03 .03 .06 .08 .08 .08 .11 .10 .09 .12 .13 637.34 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) SEPTEMBER 3.3 3.2 e3.9 e3.5 e6.3 e4.4 e3.9 e3.9 e7.6 • 3.5 3.4 3.2 3.1 4.0 3.6 6.1 4.1 4.6 41 31 14 19 ell e6.4 5.3 .9 .7 .6 .5 .8 226.8 11 12 12 11 72 131 109 96 114 56 33 25 19 20 22 38 19 24 483 601 896 635 196 90 55 35 30 27 20 13 —— .11 .10 e.ll e.ll e2.2 el. 7 el.l e.98 e4.1 .57 .29 .22 .16 .28 .23 1.0 .21 .41 230 103 37 45 e7.4 el. 6 .82 .48 .39 .33 .24 .17 --- 440.31 276 RIO GRANDB DB LOIZA BASIN 50055100 RIO CAGUITAS NEAR AGUAS BUBNAS, PR--Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1991 TO PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEPTEMBER 1992 SEDIMENT DATE OCT 1991 02. .. JAN 1992 05... DIS- CHARGE, INST. CUBIC FEBT TIME PER SECOND 0915 13 1752 1550 SEDI- MENT, SUS- PENDED (MG/L) 2070 7960 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 72 33300 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM 64 31 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM 73 37 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 74 44 SED. SBD. SED. SBD. SED. SBD. SBD. SUSP. SUSP. SUSP. SUSP. SUSP. SUSP. SUSP. PALL PALL SIEVE SIEVE SIEVE SIEVE SIEVE DIAM. DIAM. DIAM. DIAM. DIAM. DIAM. DIAM. PERCENT PERCENT PERCENT PERCENT PERCENT PERCENT PERCENT FINER FINER FINER FINER FINER FINER FINER DATE OCT 1991 02.. . JAN 1992 05... THAN THAN .016 MM .031 MM 76 51 80 60 THAN .062 MM 99 76 THAN THAN THAN THAN .125 MM .250 MM .500 MM 1.00 MM 99.4 85 99.8 94 100 98 100 99 RIO GRANDB DB LOIZA BASIN 50055100 RIO CAGUITAS NEAR AG0AS BUBNAS, PR--Continued WATER QOALITY DATA, WATER YBAR OCTOBER 1991 TO SBPTBMBBR 1992 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT 277 DATB NOV 1991 07.. . JAN 1992 05... 05... 05... 07... MAY 16... SEP 18. .. 22.. . 22... TIME 1521 1657 1927 2052 1450 1845 1622 1725 1931 STREAM- PLOW, INSTAN- TANEOUS (CFS) SEDI- MENT, SUS- PENDED (MG/L) SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 5.9 706 943 602 11 2.8 5.3 46 41 813 7700 3840 2860 50 1700 343 1340 1540 13 14600 9760 4650 1.5 13 5 166 170 100 87 87 84 99 99 98 98 99 21'8 RIO GRANDB DB LOIZA BASIN 50055225 RIO CAGUITAS AT VILLA BLANCA AT CAGUAS, PR LOCATION.--Lat 18°14'55", long 66°01'40', Hydrologic Unit 21010005, on left bank, at C. 4 street Villa Blanca housing area at Caguas, 1.8 mi (2.9 km) upstream from Rio Grande de Loiza, and 0.95 mi (1.53 km) northeast from Caguai Plaza. DRAINAGE AREA.--11.71 mi 1 (30.33 km'). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—December 1990 to current year. GAGE.--Water-stage recorder. Elevation of gage is 164 ft (50 m), froa topographic map. REMARKS.--Records fair. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AOG SEP 1 31 35 2 42 23 3 29 17 4 23 14 5 21 13 6 19 30 7 15 105 8 15 206 9 13 75 10 13 33 11 13 26 12 11 22 13 9.8 38 14 9.4 25 15 10 21 16 9.5 23 17 9.5 20 18 8.0 19 19 7.5 18 20 7.2 19 21 7.0 32 22 92 44 23 23 23 24 12 26 25 9.6 22 26 9.2 19 27 8.8 34 28 8.6 18 29 56 17 30 54 18 31 25 —— TOTAL 621.1 1035 MEAN 20.0 34.5 MAX 92 206 MIN 7.0 13 MED 13 23 AC- FT 1230 2050 CFSM 1.71 2.95 IN. 1.97 3.29 STATISTICS OF MONTHLY MEAN MEAN 20.0 34.5 MAX 20.0 34.5 (WY) 1992 1992 MIN 20.0 34.5 (WY) 1992 1992 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE ANNUAL RUNOFF (AC- FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 15 16 25 28 19 17 17 18 16 14 14 18 16 22 17 14 14 14 14 28 32 18 18 14 13 14 14 13 12 15 13 532 17.2 32 12 16 1060 1.47 1.69 DATA 17.2 17.2 1992 17.2 1992 FOR 11 12 12 12 1930 1160 60 36 36 36 24 21 22 19 18 50 43 21 17 16 16 16 15 14 16 17 14 13 13 14 12 3716 120 1930 11 17 7370 10.2 11.80 FOR WATER 70.1 120 1992 20.3 1991 11 11 12 12 12 12 13 11 11 27 12 11 11 13 11 9.9 9.8 9.7 9.2 8.1 8.1 9.3 8.8 10 8.8 9.7 8.1 7.3 7.0 --- 313.8 10.8 27 7.0 11 622 .92 1.00 YEARS 1991 17.2 23.8 1991 10.8 1992 6.7 7.6 6.7 8.4 9.3 7.8 6.9 7.2 7.2 6.7 6.7 6.9 7.0 7.0 10 6.9 12 12 12 15 11 8.5 8.1 7.5 6.8 7.2 7.2 12 16 8.3 8.9 271.5 8.76 16 6.7 7.6 539 .75 .86 - 1992 12.1 15.3 1991 8.76 1992 1991 CALENDAR YEAR 6891. 18. 360 5. 5. 13670 1. 21. 32 13 6. 1 9 Jul 16 6 Jun 29 9 Aug 3 61 89 8 8.7 7.7 8.0 7.8 7.6 6.7 12 8.7 8.2 8.1 8.9 9.9 8.2 7.8 9.1 8.1 11 10 23 28 11 10 9.7 8.1 8.1 7.5 7.2 7.2 8.2 9.9 --- 294.4 9.81 28 6.7 8.2 584 .84 .94 26 25 9.8 8.1 7.2 17 10 8.2 7.9 7.2 7.9 22 11 8.8 9.3 29 150 24 17 23 19 22 159 124 43 39 32 22 18 18 15 939.4 30.3 159 7.2 18 1860 2.59 2.98 13 12 12 70 19 15 23 18 14 26 18 27 26 14 12 23 13 11 12 12 20 13 14 12 11 10 9.2 9.2 9.2 9.0 — - 506.6 16.9 70 9.0 13 1000 1.44 1.61 8.8 8.7 8.5 9.7 16 9.4 9.2 16 10 9.4 28 10 11 8.5 8.2 12 19 13 11 9.4 13 19 11 11 16 11 11 8.9 8.1 8.2 11 364.0 11.7 28 8.1 11 722 1.00 1.16 8.7 11 14 31 570 81 40 24 18 18 24 18 16 18 16 15 16 13 12 11 11 12 12 22 9.8 9.8 9.8 11 16 11 20 1119.1 36.1 570 8.7 16 2220 3.08 3.56 14 11 16 15 54 28 24 21 45 18 15 15 15 15 17 42 27 20 327 172 103 143 48 28 18 15 14 16 15 16 --- 1327 44.2 327 11 18 2630 3.78 4.22 , BY WATER YEAR (WY) 11.1 12.4 1991 9.81 1992 FOR 1992 11039. 30. 1930 6. 6. 13400 19. 21900 2. 35. 33 14 8. 23.8 30.3 1992 17.2 1991 WATER YEAR 9 2 Jan 5 7 Mar 1 9 Mar 7 Jan 5 91 Jan 5 58 07 1 13.7 16.9 1992 10.5 1991 18.7 25.6 1991 11.7 1992 WATER 30 30 30 1930 5 5 13400 19 21850 2 35 32 13 7 25.0 36.1 1992 13.8 1991 YEARS 1991 - .2 .2 .2 Jan 5 .6 Jun 29 . 9 Aug 3 Jan 5 .91 Jan 5 .58 .00 .2 30.3 44.2 1992 16.4 1991 1992 1992 1992 1992 1991 1991 1992 1992 RIO GRANDB DB LOIZA BASIN 50055225 RIO CAOOITAS AT VILLA BLANCA AT CAOOAS, PR--Continued WATER QUALITY RECORDS PERIOD OP RECORD.-- OCTOBER 1990 TO CURRENT YEAR 279 DATS TIME MAR. 03 1407 JON. 02 1350 STRBAMFLOW, INSTANTANEOUS (CPS) 7.10 12.5 SPECIFIC CON- DUCTANCE (UMHOS) 420 410 TEMPERA- TURE (DBG C) 28.0 32.0 STRBAMFLOW, SPECIFIC CON- DATE TIME INSTANTANEOUS DOCTANCB (CFS) AUG. 28 1120 10 (UMHOS) 420 TEMPERA- TURE (DBG C) 30.0 280 RIO GRANDB DB LOIZA BASIN 50055225 RIO CAGUITAS AT VILLA BLANCA AT CAGUAS, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORDS.-- Water years 1991 to current year. INSTRUMENTATION.-- DH-48 and automatic sediment sampler. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGES December 1990 to September 1992 EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATIONS Maximum daily mean, 1,430 mg/L Jan. 05, 1992; Minimum daily mean, 5 mo/L Several days. SEDIMENT LOADSt Maximum daily mean, 8,820 tons (8,000 tonnes) Jan. 05, 1992; Minimum daily mean, 0.16 ton (0.14 tonne) Oct. 28, 1991. EXTREMES FOR WATER YEARS 1991-92.-- Water Suspended- sediment concentration (mg/L) Year maximum minimum 1991 1992 1, 770 (Jul. 430 (Jan. 16) 20 06) 5 (Several days) (Several days) SEDIMENT DISCHARGE, SUSPENDED ( TONS / DAY ), OAY MEAN DISCHARGE (CFS) MEAN CONCEN- TRATION (MG/L) SEDIMENT DISCHARGE (TONS /DAY) MEAN DISCHARGE (CPS) Suspended -sediment dischargi maximum 902 8,820 (Jul (Jan . 16) . 06) WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN CONCEN- TRATION (MG/L) SEDIMENT DISCHARGE (TONS /DAY) MEAN DISCHARGE (CPS) MEAN CONCEN TRATI01 (MG/L) minimum .35 (Several days) .16 (Oct. 28) SEDIMENT I DISCHARGE (TONS/DAY) OCTOBER NOVEMBER DECEMBER 1 —— —— —— —— —— ___ —— —— —— 2 —— —— —— —— —— —- —— —— —— 3 4 5 —— —— ___ ___ —— ___ _-- —— —— 6 —— —— -— —— —— —— —— —— —— 7 —— —— ___ ___ —— ___ —— —— —— 8 9 —— —— ___ —— —— ___ —— —— —— 10 —— —— --- —— —— _-- —— —— —— 11 12 13 --- —— —— —— —— ___ —— —— —— 14 15 16 —— —— -— —— —— --- —— —— —— 17 —— —— ___ —— —— —— ___ —— —— 18 19 20 —— —— -— —— —— —— —— —— —— 21 —— —— —— -_- —— --_ —— —— —— 22 —— —— --- —— —— --- --- —— —— 23 24 —— —— --- —— —— —— —— —— —— 25 26 —— —— --- —— —— —— —— —— —— 27 28 —— —— --- —— —— —— 16 87 3.8 29 —— —— --- —— —— —— 39 152 28 30 —— —— -— —— —— —— 46 200 27 31 —— —— --- —— —— —— 357 546 628 TOTAL —— —— -— —— —— —— —— —— —— RIO GRANDS DE LOIZA BASIN 281 50055225 RIO CAGUITAS AT VILLA BLANCA AT CAGUAS, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) JANUARY MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) FEBRUARY 97 37 26 22 23 29 23 23 20 25 22 19 16 15 16 16 15 14 15 14 16 12 13 13 13 13 13 12 12 12 13 266 151 125 112 110 114 118 116 100 110 114 102 92 87 85 87 88 83 84 81 78 72 74 75 75 75 75 70 69 76 86 85 15 9.2 7.0 6.7 8.5 7.6 8.5 5.3 7.1 7.0 5.5 4.1 3.6 3.6 3.8 3.6 3.2 3.4 3.1 3.2 2.6 2.5 2.6 2.6 2.6 2.6 2.3 2.2 2.5 2.9 14 13 14 14 119 45 30 18 15 14 28 50 39 24 21 16 14 22 35 20 17 13 13 12 13 10 9.8 13 97 110 121 117 257 170 146 103 85 79 125 161 328 245 145 66 81 110 172 142 90 85 114 180 235 281 232 118 3.5 3.9 4.4 4.4 181 25 12 5.3 3.5 3.2 12 45 36 15 8.2 3.2 3.1 7.8 17 7.9 4.2 3.1 4.0 5.9 8.0 7.9 6.2 4.3 MEAN DISCHARGE (CPS) 12 10 13 16 19 25 14 15 13 10 11 11 11 13 12 9.8 8.9 14 11 11 11 73 32 16 14 17 12 11 10 10 10 MEAN CONCEN- TRATION (MG/L) MARCH 63 39 49 66 114 130 83 88 80 75 76 109 150 154 136 117 99 82 92 72 72 308 306 236 170 124 68 67 120 202 252 SEDIMENT DISCHARGE (TONS/DAY) 1.9 1.1 1.8 2.7 6.6 11 3.1 3.8 2.9 2.1 2.2 3.2 4.4 5.2 4.5 3.3 2.4 3.0 2.8 2.1 2.1 76 26 10 6.6 6.3 2.3 2.0 3.3 5.4 6.8 TOTAL £29 229.4 665.8 445.0 475.7 216.9 282 RIO GRANDB DH LOIZA BASIN 50055225 RIO CAGOITAS AT VILLA BLANCA AT CAGUAS, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 IAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CPS) 10 10 11 12 13 13 13 38 16 11 13 23 21 12 14 12 9.8 9.5 9.5 9.8 11 10 9.0 8.9 9.3 8.9 8.6 8.1 7.9 8.5 ___ MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) APRIL 218 145 92 71 74 75 75 128 80 65 79 109 106 77 86 95 95 88 68 43 33 30 36 44 42 40 40 40 41 48 5.9 3.9 2.6 2.2 2.5 2.6 2.6 19 3.4 1.9 3.3 9.9 7.0 2.6 3.5 3.2 2.6 2.2 1.7 1.1 .96 .84 .84 1.0 1.0 .94 .94 .88 .84 1.2 MEAN DISCHARGE (CPS) 10 9.6 13 9.2 8.7 10 16 26 19 15 34 36 14 13 13 13 12 23 43 26 17 16 13 12 37 17 13 12 12 11 10 MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) MAY 44 47 51 57 60 68 84 115 101 74 142 142 63 80 132 168 125 111 149 110 93 51 23 34 120 44 33 28 25 25 25 1.2 1.2 1.8 1.4 1.4 2.1 4.1 12 5.4 3.3 18 19 2.5 2.7 4.6 5.7 4.1 7.7 26 9.4 4.7 2.4 .77 1.1 17 2.0 1.2 .91 .78 .74 .68 MEAN DISCHARGE (CFS) 11 10 9.5 10 IS 15 11 10 8.5 7.4 9.5 14 7.9 7.2 7.7 7.8 6.7 6.5 6.7 6.3 6.5 6.5 13 7.8 6.3 7.6 5.8 6.7 5.6 61 MEAN CONCEN- TRATION (MG/L) JUNE 25 25 26 27 69 59 29 79 103 89 63 65 21 21 21 21 21 21 22 22 22 22 64 39 25 29 30 47 49 190 SEDIMENT DISCHARGE (TONS/DAY) .77 .70 .67 .72 3.9 3.7 .86 2.0 2.3 1.7 2.2 3.3 .43 .40 .43 .43 .38 .37 .39 .35 .41 .39 3.7 .88 .43 .57 .49 1.0 .76 108 TOTAL 370.8 93.14 533.5 165.88 314.5 142.63 RIO QRANDB DB LOIZA BASIN 500SS22S RIO CAGOITAS AT VILLA BLANCA AT CAGUAS, PR—Continued SEDIMENT DISCHARGE, 80SFENDED (TONS/DAY), WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AUGUST 283 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 93 16 9.0 8.1 8.1 7.6 10 12 11 7.3 6.8 6.7 6.4 6.3 55 360 30 18 19 14 10 9.3 9.1 12 8.7 6.9 6.7 6.4 e6.4 e6.4 e6.6 JULY 232 128 65 42 51 80 99 71 70 42 25 24 29 32 142 770 163 132 134 91 72 50 38 69 36 21 20 20 22 29 38 100 6.1 1.6 .91 1.1 1.7 2.8 2.5 2.0 .87 .46 .44 .51 .54 64 902 14 6.6 8.1 3.5 2.0 1.3 .88 2.7 .85 .39 .35 .36 e.41 e.SS e.65 e7.0 e6.4 e6.0 eS.8 eS.8 e6.0 e6.0 e6.0 eS.8 e6.0 eS.8 e6.0 eS.8 e6.0 e6.1 e6.6 e6.8 e6.2 e6.0 e6.0 e7.0 e65 e20 e9.0 e8.3 e8.0 H26 e37 e9.2 e8.4 e8.0 39 43 47 45 41 40 40 40 103 89 63 45 40 60 83 55 40 36 32 31 45 205 105 49 40 39 353 308 108 69 52 e.62 e.74 e.75 e.71 e.64 e.64 e.64 e.64 el. 7 el. 5 e.98 e.73 e.62 e.97 el. 3 e.93 • .90 e.59 e.51 e.50 e.86 el40 e7.1 el. 2 e.89 e.86 e223 e39 e2.7 el. 6 el.l MEAN DISCHARGE (CFS) MEAN CONCEN- TRATION (MG/L) SEDIMENT DISCHARGE (TONS/DAY) SEPTEMBER e7.8 e8.0 e7.8 e7.8 e7.4 e7.1 e7.4 e7.7 e8.0 e8.1 e7.9 e7.7 e7.7 e7.8 e7.3 e7.4 e!20 elS e20 e!3 elS e25 e27 e!8 e!3 ell e!2 e21 •35 e25 50 44 49 70 88 97 99 101 100 48 32 27 44 71 75 70 352 149 152 116 139 152 178 £8 41 34 32 86 195 127 •1.2 e.95 e.98 el. 4 el. 8 el. 9 el. 9 e2.1 e2.6 el.O e.69 e.57 e.90 el. 5 el. 5 el. 4 e!66 e6.7 e21 e5.3 e8.0 e!3 e22 e2.8 el. 7 el.l e.96 eS.9 e25 e6.8 TOTAL 792.8 1130.17 428.0 434.92 492.9 308.65 e Estimated 284 RIO GRANDB DE LOIZA BASIN 50055225 RIO CAGOITAS AT VILLA BLANCA AT CAGUAS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) OCTOBER 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 31 42 29 23 21 19 15 15 13 13 13 11 9.8 9.4 10 9.5 9.5 8.0 7.5 7.2 7.0 92 23 12 9.6 9.2 8.8 8.6 56 54 25 74 93 44 17 11 12 8 7 8 10 12 12 11 10 10 10 10 10 10 10 10 165 59 28 14 8 7 7 103 112 61 6.4 11 3.7 1.1 .63 .61 .34 .31 .29 .34 .40 .35 .27 .25 .27 .28 .25 .22 .20 .20 .19 213 4.5 .97 .37 .21 .17 .16 121 58 4.6 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) NOVEMBER MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) DECEMBER 35 23 17 14 13 30 105 206 75 33 26 22 38 25 21 23 20 19 18 19 32 44 23 26 22 19 34 18 17 18 116 56 49 17 10 54 224 328 286 70 30 16 59 55 39 27 19 13 10 10 48 46 9 24 6 5 72 24 10 31 24 3.6 2.5 .65 .36 7.9 121 278 86 6.4 2.1 .99 14 3.8 2.2 1.7 1.0 .68 .49 .52 10 6.9 .58 2.2 .34 .26 9.3 1.2 .45 1.7 15 16 25 28 19 17 17 18 16 14 14 18 16 22 17 14 14 14 14 28 32 18 18 14 13 14 14 13 12 15 13 22 13 47 30 13 12 10 8 7 5 5 5 5 5 5 5 5 5 5 40 72 28 10 14 28 41 26 14 7 26 35 .90 .57 4.6 2.4 .«7 .56 .44 .41 .30 .20 .19 .23 .23 .27 .22 .19 .20 .20 .20 5.1 6.7 1.4 .48 .54 1.0 1.5 .99 .47 .23 1.5 1.2 TOTAL 621.1 430.58 1035 590.82 532 34.09 RIO GRANDS DE LOIZA BASIN 285 50055225 RIO CAGOITAS AT VILLA BLANCA AT CAGUAS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) (CFS) (MG/L) (TONS/DAY) JANUARY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 11 12 12 12 1930 1160 60 36 36 36 24 21 22 19 18 50 43 21 17 16 16 16 15 14 16 17 14 13 13 14 12 33 30 27 23 621 1430 93 21 34 83 48 30 20 14 11 225 240 21 20 18 13 9 8 6 5 5 5 6 8 11 14 1. . . 8220 6730 17 2. 5. 8. 3. 1. 1. . • 155 53 1. , . . . . 0 95 85 73 0 1 0 2 7 2 73 52 2 93 80 55 38 32 25 22 20 18 22 31 40 45 11 11 12 12 12 12 13 11 11 27 12 11 11 13 11 9 9 9 9 8 8 9 8 10 8 9 8 7 7 - - FEBRUARY .9 .8 .7 .2 .1 .1 .3 .8 .8 .7 .1 .3 .0 --— 15 16 17 18 18 17 15 14 12 55 17 15 13 27 29 25 25 29 39 50 55 55 54 51 47 45 46 52 58 ___ .46 .49 .56 .58 .56 .53 .52 .43 .37 5.2 .57 .45 .39 1.1 .87 .66 .65 .77 .98 1.1 1.2 1.4 1.3 1.4 1.1 1.2 1.0 1.0 1.1 ___ MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MARCH 6.7 7.6 6.7 8.4 9.3 7.8 6.9 7.2 7.2 6.7 6.7 6.9 7.0 7.0 10 6.9 12 12 12 15 11 8.5 8.1 7.5 6.8 7.2 7.2 12 16 8.3 8.9 63 66 67 64 59 50 43 39 37 38 39 40 40 38 36 34 32 30 28 26 25 25 26 26 25 23 21 30 54 36 35 1.1 1.3 1.2 1.5 1.5 1.1 .80 .76 .73 .68 .70 .75 .74 .73 1.0 .62 1.1 .99 .85 1.1 .78 .56 .56 .53 .47 .44 .40 1.5 2.6 .82 .84 TOTAL 3716 15207.39 313.8 27.94 271.5 28.75 286 RIO GRANDS DB LOIZA BASIN 50055225 RIO CAGDITAS AT VILLA BLANCA AT CAGUAS, PR--Continu«d SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 IS 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 8.7 7.7 8.0 7.8 7.6 6.7 12 8.7 8.2 8.1 8.9 9.9 8.2 7.8 9.1 8.1 11 10 23 28 11 10 9.7 8.1 8.1 7.5 7.2 7.2 8.2 9.9 --- APRIL 37 36 29 22 19 16 36 29 26 25 24 25 25 25 22 19 27 26 53 65 29 27 29 30 29 27 25 24 23 61 ___ MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MAY .85 .75 .62 .47 .38 .29 1.3 .66 .57 .54 .59 .67 .56 .52 .55 .42 .97 .74 8.6 6.3 .86 .71 .76 .67 .64 .56 .50 .45 .61 1.6 26 25 9.8 8.1 7.2 17 10 8.2 7.9 7.2 7.9 22 11 8.8 9.3 29 150 24 17 23 19 22 159 124 43 39 32 22 18 18 IS 84 63 40 33 29 80 95 92 90 87 83 99 70 56 45 70 240 108 57 69 94 77 313 251 92 90 76 49 52 56 60 13 5.6 1.1 .72 .56 4.0 2.6 2.0 2.0 1.7 1.8 11 2.2 1.3 1.1 10 391 8.5 2.8 5.3 4.8 4.9 403 190 12 10 7.2 2.9 2.5 2.8 2.5 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) JUNE 13 12 12 70 19 15 23 18 14 26 18 27 26 14 12 23 13 11 12 12 20 13 14 12 11 10 9.2 9.2 9.2 9.0 ___ 61 59 57 157 50 37 58 49 44 59 42 77 54 35 30 35 10 10 10 9 57 24 18 14 11 24 21 18 18 19 2.1 2.0 1.9 81 2.7 1.7 5.4 2.5 1.7 5.5 2.1 7.2 4.0 1.3 .94 3.0 .37 .30 .32 .28 3.5 .87 .68 .47 .32 .68 .52 .44 .45 .47 TOTAL 294.4 33.71 939.4 1110.88 506.6 134.71 RIO GRANDB DE LOIZA BASIN 50055225 RIO CAGUITAS AT VILLA BLANCA AT CAGUAS, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 287 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CPS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL YEAR 8.8 8.7 8.5 9.7 16 9.4 9.2 16 10 9.4 28 10 11 8.5 8.2 12 19 13 11 9.4 13 19 11 11 16 11 11 8.9 8.1 8.2 11 364.0 11039.9 JULY 22 27 31 36 84 87 75 48 18 10 54 27 47 59 43 36 39 7 18 33 38 52 32 30 37 25 21 16 15 13 29 —— MEAN MEAN MEAN CONCBN- SEDIMENT MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) (CPS) (MG/L) (TONS/DAY) AUGUST .52 .62 .71 .95 3.7 2.3 1.9 2.2 .50 .25 13 .76 1.6 1.4 .93 1.3 2.5 .24 .57 .83 1.7 3.4 .90 .91 1.8 .78 .59 .38 .31 .29 1.0 48.84 22779.11 8.7 11 14 31 570 81 40 24 18 18 24 18 16 18 16 15 16 13 12 11 11 12 12 22 9.8 9.8 9.8 11 16 11 20 1119.1 21 17 32 145 526 321 76 56 39 33 97 62 48 36 28 24 22 20 19 25 33 38 39 62 32 26 24 20 45 53 38 —— .49 .51 2.3 24 2080 127 11 3.9 1.9 1.6 8.3 3.1 2.0 1.7 1.2 .94 .97 .69 .61 .71 1.0 1.2 1.2 4.6 .83 .69 .63 .58 2.5 1.6 2.0 2289.75 SEPTEMBER 14 11 16 15 54 28 24 21 45 18 15 15 15 15 17 42 27 20 327 172 103 143 48 28 18 15 14 16 15 16 --- 1327 29 20 14 10 127 71 54 56 100 25 26 28 29 30 31 104 61 34 724 1090 443 367 150 253 295 120 27 19 19 21 --- —— 1.1 .59 .58 .41 42 5.4 3.4 5.0 18 1.2 1.1 1.1 1.1 1.3 1.4 14 4.7 1.8 1780 579 139 177 22 18 14 5.0 1.0 .80 .77 .90 --- 2841.65 288 RIO GRANDB DB LOIZA BASIN 50055225 RIO CAGUITAS AT VILLA BLANCA AT CAGUAS, PR—Continued HATER QUALITY DATA, HATER YEARS JULY 1991 TO SEPTEMBER 1992 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT DATE JUL 1991 16. .. AUG 22. .. 27... OCT 22. .. NOV 08... JAN 1992 05. .. 05... MAY 17. .. TIME 1348 1102 1610 1622 2322 1702 1952 DIS- CHARGE, INST. CUBIC FEET PER SECOND 427 393 774 869 292 2882 8476 SEDI- MENT, SUS- PENDED (MG/L) 2010 2330 1260 1800 1170 4450 2540 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 2320 2470 2630 4200 922 34600 58100 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM 55 35 43 37 60 39 43 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM 66 42— 46 67 50 52 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 72 48 49 53 — 68 62 1855 1190 3350 10700 35 41 48 DATE JUL 1991 16.. . AUG 22... 27... OCT 22... NOV 08... JAN 1992 05.. . 05.. . MAY 17... SBD. SUSP. FALL DIAM. PERCENT FINER THAN .016 MM 78 60 -- 64 70 75 75 60 SBD. SUSP. PALL DIAM. PERCENT FINER THAN .031 MM 82 69 69 71 74 81 81 72 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 97 86 94 90 98 98 98 94 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 98 93 98 95 99 99.3 99 97 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 99 97 99 98 99.6 99.8 99.8 99 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 99.8 98 100 99 100 100 100 99.7 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 100 99 100 100 100 100 100 100 RIO GRANDE DE LOIZA BASIN 50055225 RIO CAGUITAS AT VILLA BLANCA AT CAGUAS, PR--Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 SILT AND CLAY PERCENT OP SUSPENDED SEDIMENT 289 DATE OCT 1991 22.. . 22.. . NOV 07.. . 08... 08.. . 08.. . DEC 26.. . JAN 1992 05.. . 05.. . 05.. . 16.. . 16.. . 17.. . MAY 17.. . 24.. . JON 03.. . AUG 05.. . SEP 19. . . 19.. . 22.. . TIME 1642 1740 1243 1902 2027 2212 1253 1622 2007 2202 2052 2242 0027 1655 1255 1524 0357 1722 2120 1357 STREAM- FLOW, INSTAN- TANEOUS (CPS) 1310 264 106 537 484 455 13 1050 8450 2490 488 135 122 604 57 12 298 1394 1080 267 SEDI- MENT, SUS- PENDED (MG/L) 1360 615 266 1020 440 904 47 1130 771 1750 2170 1270 1135 1470 175 336 723 2080 2120 1680 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 4820 439 76 1470 575 1110 2 3210 17600 1170 2860 464 374 2400 27 11 582 7810 6200 1210 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 97 94 99 91 90 98 96 98 99 99 77 77 77 84 98 98 90 84 88 79 290 RIO GRANDB DB LOIZA BASIN 50055250 RIO CAGOITAS AT HIGHWAY 30 AT CAQUAS, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°15'11", long 66«01'26", at Highway 30 bridge, and 0.8 mi (1.3 km) east of Caguas plaza. DRAINAGE AREA.--14.1 mi* (36.5 km 1 ). PERIOD OF RECORD.--Hater year* 1972 to current year. WATER-QUALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 08... DEC 06. .. FBB 1992 13... MAY 05... JUN 10. .. AUG 20... TIME 1050 0945 0910 1110 1000 1040 DIS- CHARGE, INST. CUBIC FEET PER SECOND 38 41 33 9.7 31 28 SPE- CIFIC CON- DUCT- ANCE (US/CM) 564 594 644 651 517 630 PH HATER WHOLE FIELD (STAND- ARD UNITS) 7.3 7.3 7.1 6.7 6.6 7.0 TEMPER- ATURE HATER (DBG C) 28.0 25.5 25.5 28.5 28.0 30.0 TUR- BID- ITY (NTU) 15 3.4 1.1 3.9 14 3.0 OXYGEN, DIS- SOLVED (MG/L) 1.5 0.9 2.0 2.3 2.6 1.6 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 39 21 64 48 53 41 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 25 59 84 85 62 67 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 350000 350000 6600 20000 K100000 2900 STREP- TOCOCCI FBCAL, (COLS. PER 100 ML) K106000 33000 3600 K1100 59000 2400 DATE OCT 1991 08... DEC 06... FBB 1992 13... MAY 05... JUN 10.. . AUG 20... HARD- NESS TOTAL (MG/L AS CALCIUM DIS- SOLVED (MG/L MAGNE- SIUM, DIS- SOLVED (MG/L SODIUM, DIS- SOLVED (MQ/L SODIUM AD- SORP- TION RATIO POTAS- SIUM, DIS- SOLVED (MG/L ALKA- LINITY WAT WH TOT FBT FIELD MG/L AS SULFIDB TOTAL (MG/L SULFATB DIS- SOLVED (MG/L CHLO- RIDE, DIS- SOLVED (MQ/L CAC03) AS CA) AS MG) AS NA) AS K) 110 25 11 26 1 5.2 140 38 12 48 2 7.6 140 38 12 49 2 7.0 CACO3 170 160 180 170 90 110 AS S) AS SO4) AS CL) <0.5 14 <0.5 52 51 29 61 59 SOLIDS, RESIDUE DATE OCT 1991 08.. . DEC 06... FBB 1992 13... MAY 05.. . JUN 10... AUG 20.. . FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.10 -- -- 0.20 -- 0.20 SILICA, DIS- SOLVED (MQ/L AS SI02) 29 -- — 29 — 28 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 241 -- -- 350 _- 344 SOLIDS, DIS- SOLVED (TONS PER DAY) 24.5 — -- 9.16 -_ 26 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 30 16 25 10 23 6 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 1.58 0.230 0.120 0.100 0.510 0.130 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.220 0.130 0.060 0.080 0.100 0.080 NITRO- GEN, NO2+N03 TOTAL (MG/L AS N) 1.80 0.360 0.180 0.180 0.610 0.210 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 9.00 8.70 11.0 13.0 6.80 0.610 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 4.0 2.3 5.0 5.0 2.5 13 non-ideal count RIO QRANDB DB LOZZA BASIN 50055250 RZO CAODZTAS AT HIGHWAY 30 AT CAGUAS, PR--Continued WATER-QUALITY DATA, WATBR YBAR OCTOBER 1991 TO SEPTEMBER 1992 291 DATE OCT 1991 08... DBC 06... FBB 1992 13... MAY 05... OUN 10.. . AOG 20... DATS OCT 1991 08.. . DBC 06... FBB 1992 13... MAY 05.. . JUN 10... AOG 20... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 13 11 16 18 9.3 14 IRON, TOTAL RECOV- ERABLE (UG/L AS FE) NITRO- GEN, TOTAL (MG/L AS N) 15 11 16 18 9.9 14 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N03) 66 50 72 80 44 63 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 3.00 3.10 3.30 3.60 2.90 2.70 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) ARSENIC TOTAL (UG/L AS AS) <1 -- -- <1 -- -- SELE- NIUM, TOTAL (UG/L AS SB) BARZDM, TOTAL RECOV- ERABLE (OG/L AS BA) <100 — — <100 — — SILVER, TOTAL RECOV- ERABLE (OG/L AS AG) BORON, TOTAL RECOV- ERABLE (OG/L AS B) <10 -- -- 120 -- -- ZINC, TOTAL RECOV- ERABLE (OG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (OG/L AS CD) <1 — — <1 — — CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) <1 -- — 5 — -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CD) <10 — " 20 — — MBTHY- LBNB BLUE ACTIVE SUB- STANCE (MG/L) 1300 400 330 200 <0.10 <0.10 <1 <1 <1 30 <0.010 0.010 11 0.06 1.7 292 RIO GRANDB DB LOIZA BASIN 50055390 RIO BAIROA AT BAIROA, PR LOCATION.—Lat 18°15'32", long 66°02'24", Hydrologic Unit 21010005, on left bank, in the Bairoa Housing Area, 1.6 mi (2.6 km) northwest of Plaza de Caguas, 4.1 mi (6.6 km) east of Plaza de Aguas Buenas, and 0.9 mi (1.4 km) northwest of Bscuela Pepita Garriga. DRAINAGE ARBA.--5.08 mi 1 (13.15 km2 ). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—November 1990 to current year. GAGE.—Hater-stage recorder and crest-stage gage. Elevation of gage is 131 ft (40 m), from topographic map. REMARKS.—Records poor. Gage-height and precipitation satellite telemetry at station. Mean daily discharge affected by domestic discharge from nearby station. DAY DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 e4 . 0 17 2 e7.0 11 3 3.9 4.7 4 3.2 4.8 5 4.0 8.9 6 3.2 5.8 7 3.2 18 8 3.2 57 9 3.3 21 10 3.2 6.7 11 3.1 e5.3 12 3.1 e4.8 13 3.0 e4.6 14 3.3 e4.4 15 3.8 e4.2 16 3.4 e4.0 17 3.3 3.8 18 3.0 3.8 19 3.0 3.8 20 2.9 3.9 21 3.7 9.2 22 5.0 16 23 4.6 12 24 3.3 8.8 25 3.0 6.3 26 3.0 6.1 27 2.9 10 28 2.7 4.3 29 5.1 4.1 30 24 4.0 31 5.9 - — TOTAL 133.3 278.3 MEAN 4.30 9.28 MAX 24 57 MIN 2.7 3.8 MED 3.3 5.6 AC-FT 264 552 CFSM .85 1.83 IN. .98 2.04 e Estimated STATISTICS OF MONTHLY MEAN MEAN 14.8 8.38 MAX 25.3 9.28 (WY) 1991 1992 MIN 4.30 7.48 (WY) 1992 1991 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 3.9 3.9 e5.6 e€.4 4.6 4.3 3.9 3.8 3.9 3.9 3.9 3.9 e4.9 e5.2 4.0 3.8 3.7 3.6 3.6 e!5 e9.2 4.1 4.0 3.8 3.8 3.7 3.8 3.8 3.8 3.8 3.8 143.4 4.63 15 3.6 3.9 284 .91 1.05 DATA 7.46 10.3 1991 4.63 1992 FOR e3.8 e3.6 e3.6 e3.6 e!80 elOO elO e6.0 e5.4 5.8 4.1 3.8 4.1 3.5 3.2 22 8.2 e4.4 e3.9 e3.8 e3.8 e3.7 e3.7 e3.7 e3.8 e3.7 e3.6 e3.6 e3.6 e3.6 e3.4 423.0 13.6 180 3.2 3.8 839 2.69 3.10 e3.3 e3.4 e3.5 e3.5 e3.5 e3.5 e3.4 e3.5 e3.6 e4.3 e3.6 e3.4 e3.4 e3.4 e3.3 e3.5 e3.4 e3.4 e3.4 e3.2 e3.3 e3.2 3.7 4.0 3.3 3.2 3.6 3.5 3.4 ___ --- 100.7 3.47 4.3 3.2 3.4 200 .68 .74 FOR WATER YEARS 1991 10.8 13.6 1992 7.91 1991 5.99 8.60 1991 3.47 1992 3.0 2.8 2.8 2.8 2.8 2.8 2.8 e2.6 e2.€ e2.7 e2.€ e2.5 e2.5 e2.4 e2.7 e2.6 eS.2 e2.8 e2.7 e2.6 e2.5 e2.5 e2.4 e2.3 e2.3 e2.3 e2.3 e33 e4.0 e2.7 e2.4 115.0 3.71 33 2.3 2.6 228 .73 .84 - 1992 4.44 5.18 1991 3.71 1992 1991 CALENDAR YEAR 2405. 6. 191 2. 2. 4770 1. 17. 8. 4. 3. 1 59 Jul 16 6 Jun 16 8 Jun 13 30 61 4 0 1 e2.3 e2.4 e2.4 e2.4 e2.3 e2.4 e2.7 e2.€ e2.4 e2.3 e2.4 e2.6 e2.4 e2.2 e2.2 e2.2 e2.4 e3.7 e7.4 e3.5 e2.9 e2.5 e2.4 e2.3 e2.2 e2.2 e2.2 e2.2 e2.1 e2.2 78.4 2.61 7.4 2.1 2.4 156 .51 .57 e2.5 e3.2 e2.7 e2.3 e2.2 e2.6 e2.5 e2.3 e2.2 e2.1 e2.2 e3.0 e2.7 e2.4 e2.5 e3.5 e4.7 e3.4" e4.3 «4.7 e6.4 e4.6 e32 e30 e!4 e!2 elO 7.9 6.7 5.9 5.3 192.8 6.22 32 2.1 3.4 382 1.22 1.41 5.1 5.0 4.0 9.4 3.8 4.8 5.1 5.6 5.9 5.5 e4.5 e8.€ e8.2 e4.5 e3.8 e7.4 e4.1 e3.5 e3.8 e3.8 e6.4 e4.2 e4.5 e3.8 e3.5 e3.2 e3.0 e3.0 e3.0 e2.9 143.9 4.80 9.4 2.9 4.3 285 .94 1.05 e2.8 e2.8 e2.7 e3.1 e5.2 e3.0 e2.8 e5.2 e3.2 e3.0 e!2 e7.6 5.7 €.1 6.7 6.1 5.6 4.2 3.7 3.5 3.9 3.8 5.0 4.1 4.1 3.7 3.7 3.6 3.2 3.2 3.1 136.4 4.40 12 2.7 3.7 271 .87 1.00 3.6 3.8 4.9 15 82 18 9.5 5.8 4.7 4.5 5.7 5.1 4.4 4.9 4.4 4.2 4.3 4.3 4.0 3.8 3.6 3.7 3.4 3.8 3.2 3.4 e2.9 e3.5 e5.2 e3.5 3.8 236.9 7.64 82 2.9 4.3 470 1.50 1.73 5.4 3.4 3.2 8.3 4.4 11 49 4.0 7.5 3.6 4.4 3.1 3.9 2.8 2.9 3.1 3.4 3.3 e88 e35 elO 3.9 3.5 3.5 3.6 3.7 3.8 4.0 4.2 4.2 — - 294.1 9.80 88 2.8 3.9 583 1.93 2.15 , BY WATER YEAR (WY) 3.18 3.76 1991 2.61 1992 FOR 1992 2276. 6. 180 2. 2. 1580 12. 4510 1. 16. 8. 3. 2. 6.09 6.22 1992 5.96 1991 WATER YEAR 2 22 Jan 5 1 Apr 29 2 Apr 24 Jan 5 32 Jan 5 22 67 4 7 5 4.58 4.80 1992 4.37 1991 10.5 16.5 1991 4.40 1992 WATER 7 8 6 191 2 2 1580 12 5410 1 19 10 4 2 5.87 7.64 1992 4.09 1991 7.15 9.80 1992 4.50 1991 YEARS 1991 - 1992 .46 .71 .22 Jul .1 Apr .2 Apr Jan .32 Jan .47 .96 .0 .8 1991 1992 16 1991 29 1992 24 1992 5 1992 5 1992 RIO GRANDS DE LOIZLA BASIN 50055390 RIO BAIROA AT BAIROA, PR—Continued WATER QUALITY RECORDS PERIOD OF RECORD.-- OCTOBER 1990 TO CURRENT YEAR DATE TIME MAY 15 1440 JUN. 11 0932 STRBAMFLOW, INSTANTANEOUS (CPS) 2.48 4.0 SPECIFIC CON- DUCTANCE (UMHOS) 460 320 TEMPERA- TURE (DEC C) 27.5 25.5 DATE TIME JUL. 08 1451 AUG. 27 1255 STRBAMFLOW, INSTANTANEOUS (CFS) 5.21 2.88 SPECIFIC CON- DUCTANCE (UMHOS) 380 410 293 TEMPERA- TURE (DEC C) 27.5 30.0 294 RIO GRANDB DB LOIZA BASIN 50055390 RIO BAIROA AT BAIROA, PR—Continued WATER QUALITY DATA, HATER YEARS JULY 1991 TO SEPTEMBER 1992 PARTICLE-SIZB DISTRIBUTION OF SUSPENDED SEDIMENT DATE JUL 1991 01... 16... 16... 18... TIME 1255 1030 1120 1552 DIS- CHARGE, INST. CUBIC FEET PER SECOND 154 586 700 357 SEDI- MENT, SUS- PENDED (MG/L) 1540 4040 3910 4000 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 640 6390 7390 3850 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM 64 42 45 56 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM 69 53 54 66 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 73 63 66 79 DATE JUL 1991 01... 16... 16... 18... SED. SUSP. FALL DIAM. PERCENT FINER THAN .016 MM 75 77 79 85 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM 79 84 83 87 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 98 98 96 99 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 99 99 98 99.4 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 99.3 99.6 99 99.7 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 99.6 99.8 99.3 99.8 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 99.8 100 99.8 100 RIO ORANDB DB LOIZA BASIN 50055390 RIO BAIROA AT BAIROA, PR—Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT 295 DATS NOV 1991 08... 22... JAN 1992 07... SEP 07... TIME 1557 1250 1241 1404 STREAM- FLOW, INSTAN- TANEOUS (CFS) 29 10 10 218 SEDI- MENT, SUS- PENDED (MG/L) 422 186 115 720 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 33 5 3 423 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MI 100 99 97 97 296 RI° GRANDS DB LOIZA BASIN 50055400 RIO BAIROA NEAR CAGUAS, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°15'28", long 66°02'13", at bridge on Highway 1, about 2.5 mi (4.0 km) upstream from Rio Qrande de Loiza, and 1.4 mi (2.3 km) north of CaguaB plaza. DRAINAGE AREA.--5.4 mi 1 (14.0 km1 ). PERIOD OF RECORD.--Water years 1958, 1962-66, 1973-74, 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 16... DEC 06... FBB 1992 13... MAY 14. .. JUN 19... ADG 26... OCT 16 DEC 06 FBB 13 MAY 14 JUN 19 AUG 26 OCT 16 DEC 06 FBB 13 MAY 14 JUN 19 AUG 26 K = DIS- PH OXYGEN, OXYGEN COLI- CHARGB, SPB- WATER DIS- DEMAND, FORM, STRBP- INST. CIFIC WHOLE SOLVED CHEM- FECAL, TOCOCCI CUBIC CON- FIELD TEMPER- TOR- OXYGEN, (PER- ICAL 0.45 FECAL, FEET DUCT- (STAND- ATURB BID- DIS- CENT (HIGH UM-MF (COLS. TIME PER ANCB ARD WATER ITY SOLVED SATUR- LEVEL) (COLS./ PER SECOND (US/CM) UNITS) (DEG C) (NTD) (MG/L) ATI ON) (MG/L) 100 ML) 100 ML) 1230 3.9 440 7.6 26.5 3.8 1.9 23 20 59000 30000 1140 0.51 470 7.2 24.5 16 1.4 19 82 K63000 K80000 1000 5.1 416 7.3 23.0 0.30 7.5 102 <10 K7700 2700 0920 1.8 485 6.9 25.5 0.60 5.5 63 11 450000 330000 1235 1.0 360 7.2 28.0 2.2 7.5 104 21 2000 2100 1515 1.5 430 7.3 28.5 1.2 5.4 59 <10 41000 k!700 ALKA- HARD- NBSS TOTAL (MG/L DATE AS CACO3 ) 1991 17 0 1992 170 150 PLUO- RIDE, DIS- SOLVED DATE (MG/L AS F) 1991 0.20 1992 . . . 0.10 0.20 non- ideal count CALCIUM DIS- SOLVED (MG/L AS CA) 40 -- -- 40 -- 37 SILICA, DIS- SOLVED (MG/L AS SI02) 30 — -- 31 -- 28 MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) 16 -- -- 16 -- 15 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 266 -- -- 291 -- 259 SODIUM, DIS- SOLVED (MG/L AS NA) 30 -- -- 30 -- 26 SOLIDS, DIS- SOLVED (TONS PER DAY) 2.83 -- -- 1.40 -- 1.05 SODIUM AD- SORP- TION RATIO 1 -- -- 1 -- 0.9 RESIDUE TOTAL AT 105 DEG. C, SUS- PENDED (MG/L) <1 34 8 3 4 2 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 4.6 -- -- 4.0 -- 4.3 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 1.33 1.50 1.36 1.57 1.57 1.35 LINITY WAT WH TOT PET FIELD MG/L AS CAC03 150 150 140 150 150 160 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.070 0.100 0.040 0.030 0.030 0.050 SULFIDE TOTAL (MG/L AS S) <0.5 -- -- <0.5 -- -- NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 1.40 1.60 1.40 1.60 1.60 1.40 SULFATB DIS- SOLVED (MG/L AS 804) 20 -- -- 35 -- 21 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 1.10 4.10 0.090 0.130 0.110 0.180 CHLO- RIDE, DIS- SOLVED (MG/L AS CL) 35 — -- 45 -- 39 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.90 2.4 0.21 0.07 0.19 0.42 RIO QRANDB DB LOIZA BASIN 50055400 RIO BAIROA NEAR CAGUAS, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 297 DATE OCT 1991 16... DEC 06... FBB 1992 13... MAY 14... •TON 19.. . ADG 26.. . DATE OCT 1991 16. . . DEC 06.. . FEB 1992 13.. . MAY 14.. . JUN 19. .. AUQ 26... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 2.0 6.5 0.30 0.20 0.30 0.60 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) 230 -- -- 160 -- -- NITRO- GEN, TOTAL (MG/L AS N) 3.4 8.1 1.7 1.8 1.9 2.0 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) 1 -- -- <1 -- -- NITRO- GEN, TOTAL (MG/L AS N03) 15 36 7.5 8.0 8.4 8.9 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) 130 -- -- 110 -- -- PHOS- PHORUS TOTAL (MG/L AS P) 0.690 2.10 0.500 0.660 0.640 0.890 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) <0.10 -- -- <0.10 -- — BARIUM, TOTAL ARSENIC RBCOV- TOTAL BRABLB (UG/L (UG/L AS AS) AS BA) 2 <100 __ __ 3 <100 __ — — — — SILVER, SBLB- TOTAL NIUM, RBCOV- TOTAL BRABLB (UG/L (UG/L AS SB) AS AG) <1 <1 __ __ <1 <1 _. _-_ BORON, TOTAL RECOV- ERABLE (UG/L AS B) 40 -- -- 50 -- — — ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) <10 -- -- 20 -- -- CHRO- CADMIUM MIUM, TOTAL TOTAL RBCOV- RECOV- ERABLE BRABLB (UG/L (UG/L AS CD) AS CR) <1 1 __ __ <1 <1 — — — — — CYANIDE TOTAL PHENOLS (MG/L TOTAL AS CN) (UG/L) <0.010 3 __ __ <0.010 1 __ — COPPER, TOTAL RECOV- ERABLE (UG/L AS CD) 20 -- -- <10 — — — MBTHY- LBNE BLUB ACTIVE SUB- STANCE (MG/L) 0.07 -- -- 0.06 — — 298 RIO GRANDS DB LOIZA BASIN 50055750 RIO OORABO BELOW BL MANGO, PR LOCATION.—Lat 18°14'02", long 65°53'07", Hydrologic Unit 21010005, on left bank, 2.43 mi (3.91 km) northeast of Plaia de Juncos, 1.3 mi (2.1 km) southeast of Bscuela La Placita and 0.35 mi (0.56 km ) southwest of 81 Mango. DRAINAGE ARBA.--22.3 mi* (57.8 km*). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—March 1990 to current year. OAGB.—Water-stage recorder. Elevation of gage is 230 ft (70 m), from topographic Bap. REMARKS.--Records fair. Gage-height and precipitation satellite telemetry at station. Low-flow is affected by sewage discharges from a water treatment plant, 0.60 mi (0.96 km) upstream from gaging station since 1990. DISCHARGE, CUBIC FEET PER SECOND, WATBR YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DBC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 158 6.0 2 244 39 3 144 12 4 46 10 5 39 23 6 26 52 7 16 456 8 12 1420 9 14 260 10 14 215 11 14 76 12 10 43 13 11 35 14 10 28 15 11 24 16 26 23 17 12 22 18 9.9 19 19 9.0 18 20 7.2 16 21 6.5 25 22 €.3 142 23 6.2 28 24 €.0 95 25 6.1 31 26 5.2 19 27 5.0 41 28 4.7 29 29 4.9 21 30 5.8 35 31 5.4 TOTAL 895.2 3263.0 MEAN 28.9 109 MAX 244 1420 KIN 4.7 6.0 AC-FT 1780 6470 CFSM 1.29 4.88 IN. 1.49 5.44 STATISTICS OF MONTHLY MEAN MEAN 94.9 72.1 MAX 161 109 (HY) 1991 1992 MIN 28.9 35.5 (WY) 1992 1991 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 28 34 €4 140 29 20 16 15 16 16 16 15 16 19 15 14 18 13 13 32 74 17 15 13 12 11 11 11 11 11 11 746 24.1 140 11 1480 1.08 1.24 DATA 41.5 59.0 1991 24.1 1992 FOR 13 12 11 10 550 €99 140 52 35 111 37 27 31 27 20 19 17 16 16 16 15 15 15 16 18 20 19 16 18 16 14 2041 65.8 €99 10 4050 2.95 3.40 FOR WATBR 51.0 65.8 1992 36.2 1991 14 14 14 18 17 46 34 17 14 14 15 12 11 11 11 11 8.9 8.3 8.3 7.9 8.0 7.5 7.8 7.8 8.0 8.3 9.7 8.8 8.4 ___ 380.7 13.1 46 7.5 755 .59 .64 YEARS 1990 28.3 44.0 1991 13.1 1992 6.9 7.2 7.7 8.4 16 8.4 49 37 10 7.3 6.1 5.7 5.7 5.7 15 7.7 €.4 8.9 8.9 6.8 6.1 7.5 8.8 6.4 5.8 5.4 5.1 5.0 4.8 4.7 4.6 299.0 9.65 49 4.6 593 .43 .50 - 1992 13.9 18.1 1991 9.65 1992 1991 CALENDAR YEAR 12213. 33. 1420 1. 1. 24220 1. 20. 71 12 3. 2 5 Nov 8 5 Aug 12 7 Aug 8 50 37 9 4.7 5.2 4.7 4.4 4.3 4.3 5.0 5.5 13 22 7.6 6.4 9.1 7.2 7.9 6.6 5.7 5.6 78 26 11 7.4 6.3 5.8 5.3 5.0 4.9 4.7 4.6 4.7 --- 292.9 9.76 78 4.3 581 .44 .49 , BY WATBR 8.73 9.76 1992 7.52 1990 16 168 11 6.5 5.3 482 102 15 8.1 6.7 13 10 5.6 4.8 4.7 6.8 8.8 5.4 4.7 9.6 8.6 5.1 765 657 256 880 122 41 25 20 153 3826.7 123 880 4.7 7590 5.54 6.38 YEAR (WY) 48.0 123 1992 4.83 1990 448 224 31 190 103 101 258 109 46 399 141 537 180 167 40 160 111 25 16 14 68 35 76 14 8.0 5.9 5.2 4.6 3.8 3.3 --- 3523.8 117 537 3.3 6990 5.27 5.88 52.3 117 1992 14.7 1991 FOR 1992 WATBR YEAR 19150.0 52.3 1420 1.4 2.0 5870 17.38 1.4 37980 2.35 31.95 122 12 4.7 Nov 8 Jul 14 Jul 10 Nov 8 Nov 8 Jul 13 3.0 2.6 2.4 2-3 2.2 1.9 1.7 2.1 3.2 2.4 2.1 2.3 1.5 1.4 1.6 2.5 12 5.0 2.8 2.7 5.6 82 7.6 135 38 9.6 25 24 6.2 4.1 3.4 397.6 12.8 135 1.4 789 .58 .66 23.9 33.1 1990 12.8 1992 WATBR 47 52 41 1420 1 1 5870 17 1 34040 2 28 94 12 3 3.4 4.1 5.0 4.3 405 36 29 31 13 11 24 31 36 154 50 22 30 14 11 11 9.7 8.7 8.2 11 8.9 8.0 7.9 7.4 7.3 7.1 18 1027.0 33.1 405 3.4 2040 1.49 1.71 34.1 35.2 1990 33.1 1992 YEARS 1990 .0 .3 .6 Nov .4 Jul .7 Aug Nov .38 Nov .4 Jul .11 .63 .9 14 8.8 9.4 8.2 7.4 21 13 9.4 16 12 8.7 8.7 7.1 6.5 6.2 23 122 28 255 945 815 35 14 16 8.0 6.5 6.1 7.5 3.6 16--- 2457.1 81.9 916 3.6 4870 3.67 4.10 53.8 81.9 1992 34.9 1990 - 1992 1992 1991 8 1991 14 1992 8 1991 8 1991 8 1991 13 1992 299 RIO GRAHDB DB LOIZA BASIN 50055750 RIO GORABO BELOW EL MANGO, PR--Continued WATER QUALITY RECORDS PERIOD OF RECORD.--OCTOBER 1990 TO CURRENT YBAR STREAM? LOW, DATS TIME INSTANTANBOOS (CFS) MAR. 16 0855 JUN. 03 1037 JUN. 23 0921 7.58 31.3 87.7 SPECIFIC CON- TEMPERA- DOCTANCB TORE (OMHOS) (DBG C) DATE TIME 300 240 220 24.5 26.0 26.5 JUL. 14 0844 AUG. 21 0952 STREAM?LOW, INSTANTANBOOS (CFS) 1.37 9.73 SPECIFIC CON- TBMPBRA- DOCTANCB TORE (OMHOS) (DBG C) 420 350 28.0 31.0 300 RI° GRANDE DB LOIZA BASIN 50055750 RIO GORABO BELOW EL MANGO, PR—Continued WATBR-QDALITY RECORDS PERIOD OF RECORDS.-- Water years 1985 to 1986 and water year 1989 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGES March 1990 to September 1992. INSTRUMENTATION.— DH-48 and automatic sediment sampler. n, 1,000 mg/L Oct. 21, 1990; Minimum daily EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATIONS Maximum daily 4 mg/L April 7,1991. SEDIMENT LOADSi Maximum daily mean, 7,110 tons (6,450 tonnes) Nov. 08, 1991; Minimum daily mean, 0.05 ton (0.3 tonne) several days. EXTREMES FOR CURRENT YEAR.— SEDIMENT CONCENTRATIONS Maximum daily mean, 978 mg/L NOV. 08, 1991; Minimum daily mean, 5 mg/L Several days. SEDIMENT LOADSi Maximum daily mean, 7,110 tons (6,450tonnes) Nov. 08, 1991; Minimum daily mean, 0.05 ton (0.04 tonne) several days. SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CFS) 158 244 144 46 39 26 16 12 14 14 14 10 11 10 11 26 12 9.9 9.0 7.2 6.5 6.3 6.2 6.0 6.1 5.2 5.0 4.7 4.9 5.8 5.4 MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) OCTOBER 167 240 172 65 55 51 45 35 29 23 30 25 25 24 24 46 21 25 28 30 31 32 32 30 25 21 19 17 16 16 16 MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) (CFS) (MG/L) (TONS/DAY) NOVEMBER 76 180 75 8.5 6.4 3.7 2.0 1.2 1.1 .88 1.2 .70 .72 .64 .71 3.8 .71 .65 .70 .59 .54 .53 .54 .48 .41 .30 .26 .22 .21 .25 .22 6.0 39 12 10 23 52 456 1420 260 215 76 43 35 28 24 23 22 19 18 16 25 142 28 95 31 19 41 29 21 35 ___ 18 59 26 21 34 62 443 978 192 224 88 48 35 24 15 16 21 23 27 29 36 107 22 113 31 19 53 33 29 50 ___ .44 9.9 .84 .58 2.6 20 1050 7110 149 157 19 5.7 3.5 1.8 1.0 1.0 1.2 1.2 1.3 1.3 4.4 61 1.8 36 3.1 1.0 6.6 2.7 1.7 5.3 ___ DECEMBER 28 34 64 140 29 20 16 15 16 16 16 15 16 19 15 14 18 13 13 32 74 17 15 13 12 11 11 11 11 11 11 42 50 76 105 36 24 21 18 14 12 12 12 16 21 18 18 14 12 11 31 52 24 20 15 13 12 11 10 9 8 8 3.2 4.7 27 61 2.9 1.3 .93 .74 .59 .52 .51 .51 .65 1.1 .75 .69 .67 .44 .37 12 16 1.2 .77 .51 .42 .36 .32 .28 .27 .26 .24 TOTAL 895.2 369.16 3263.0 8660.96 746 141.20 RIO GRANDS DB LOIZA BASIN 307 50055750 RIO GURABO BELOW BL MANGO, PR--Continued SBDIMKNT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) JANUARY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 13 12 11 10 550 699 140 52 35 111 37 27 31 27 20 19 17 16 16 16 15 15 15 16 18 20 19 16 18 16 14 9 10 10 10 431 325 113 71 43 61 20 16 12 11 12 12 14 14 14 14 14 14 15 20 26 33 41 49 54 52 46 .32 .31 .29 .28 2650 858 45 11 4.3 26 2.0 1.2 .96 .82 .66 .64 .65 .63 .59 .59 .57 .56 .60 .88 1.3 1.8 2.0 2.2 2.6 2.2 1.7 PBBRDARY 14 14 14 18 17 46 34 17 14 14 15 12 11 11 11 11 8.9 8.3 8.3 7.9 8.0 7.5 7.8 7.8 8.0 8.3 9.7 8.8 8.4 41 35 29 23 15 46 56 17 12 13 13 13 13 13 12 13 15 16 17 13 10 6 5 5 6 6 8 10 12 1.5 1.3 1.2 1.1 .71 12 5.7 .82 .45 .50 .51 .43 .37 .37 .36 .37 .35 .35 .39 .28 .20 .12 .10 .11 .13 .15 .21 .24 .27 MEAN DISCHARGE (CPS) 6.9 7.2 7.7 8.4 16 8.4 49 37 10 7.3 6.1 5.7 5.7 5.7 IS 7.7 6.4 8.9 8.9 6.8 6.1 7.5 8.8 6.4 5.8 5.4 5.1 5.0 4.8 4.7 4.6 MEAN CONCEN- TRATION (MG/L) MARCH 15 19 14 10 36 29 50 33 27 22 20 20 17 12 22 17 12 8 10 10 10 10 11 12 13 13 13 13 13 13 14 SEDIMENT DISCHARGE (TONS/ DAY) .28 .36 .29 .25 1.7 .67 21 4.1 .76 .45 .34 .31 .27 .19 1.1 .37 .20 .18 .23 .19 .17 .20 .24 .20 .20 .19 .18 .18 .17 .16 .16 TOTAL 2041 3620.65 380.7 30.59 299.0 35.29 302 RIO QRANDB DB LOIZA BASIN 50055750 RIO OORABO BELOW BL MANGO, PR--Continued SBDIMBNT DISCHARGE, SDSPBNDBD (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN CONCBN- SBDIMBNT TRATION DISCHARGE (MG/L) (TONS/DAY) JDNB 410 1570 335 273 77 7.4 190 169 118 44 119 35 253 389 126 43 65 8.9 398 770 154 75 456 1210 185 101 172 92 59 7.2 83 98 71 26 34 2.6 25 1.2 24 .95 81 31 50 7.7 99 29 54 2.3 38 .85 29 .47 28 .39 24 .29 19 .19 17 .14 TOTAL 292.9 --- 65.74 3826.7 --- 9759.12 3523.8 --- 4995.58 MEAN MEAN CONCBN- SBDIMBNT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 4 5 4 4 4 4 5 5 13 22 7 6 9 7 7 6 5 5 78 26 11 7 6 5 5 5 4 4 4 4 - .7 .2 .7 .4 .3 .3 .0 .5 .6 .4 .1 .2 .9 .6 .7 .6 .4 .3 .8 .3 .0 .9 .7 .6 .7 -- APRIL 15 15 12 8 8 10 10 11 23 38 9 8 9 10 11 14 24 30 111 80 72 70 65 57 49 42 35 26 22 22 ... MEAN MEAN CONCBN- SBDIMBNT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MEAN DISCHARGE (CFS) MAY .19 .21 .15 .09 .10 .12 .14 .16 2.2 3.3 .19 .15 .22 .19 .24 .24 .36 .45 43 5.8 2.2 1.4 1.1 .90 .72 .57 .46 .34 .28 .27 ... 16 168 11 6 5 482 102 15 8 6 13 10 5 4 4 6 8 5 4 9 8 5 765 657 256 880 122 41 25 20 153 .5 .3 .1 .7 .6 .8 .7 .8 .8 .4 .7 .6 .6 .1 822 130 23 19 16 323 120 47 33 21 21 12 13 15 17 18 18 17 17 15 12 12 555 628 233 624 84 55 28 11 152 30 136 858 52 1 3190 1850 405 2930 30 6 2 261 .68 .34 .22 .9 .74 .38 .92 .36 .19 .19 .22 .30 .44 .24 .22 .38 .30 .17 .3 .0 .63 448 224 31 190 103 101 258 109 46 399 141 537 180 167 40 160 111 25 16 14 68 35 76 14 8 5 5 4 3 3 - .0 .9 .2 .6 .8 .3 -- RIO GRANDS DE LOIZA BASIN 303 50055750 RIO OTRABO BELOW EL MANGO, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL YEAR 3.0 2.6 2.4 2.3 2.2 1.9 1.7 2.1 3.2 2.4 2.1 2.3 1.5 1.4 1.6 2.5 12 5.0 2.8 2.7 5.6 82 7.6 135 38 9.0 25 24 6.2 4.1 3.4 397.6 19199.8 JULY 15 16 17 17 17 17 17 18 22 14 11 12 12 14 17 19 28 12 7 8 13 90 17 142 53 18 35 85 36 29 24 —— .12 .11 .10 .10 .10 .09 .08 .10 .20 .09 .07 .07 .05 .05 .07 .13 .93 .17 .05 .07 .22 41 .39 187 9.0 .48 7.9 7.3 .61 .33 .23 257.21 36905.26 AUGUST 3.4 4.1 5.0 4.3 405 36 29 31 13 11 24 31 36 154 50 22 30 14 11 11 9.7 8.7 8.2 11 8.9 8.0 7.9 7.4 7.3 7.1 18 1027.0 18 13 29 43 430 52 43 48 29 20 37 45 52 154 98 38 45 28 25 21 19 20 20 20 22 22 20 18 16 11 29 .16 .15 .38 .49 1070 6.5 3.4 4.3 1.1 .60 3.8 4.9 7.0 131 19 3.0 4.4 1.1 .74 .57 .52 .45 .46 .59 .53 .46 .43 .36 .32 .21 1.6 MEAN DISCHARGE (CFS) 14 8.8 9.4 8.2 7.4 21 13 9.4 16 12 8.7 8.7 7.1 6.5 6.2 23 122 28 255 945 819 47 21 23 12 9.9 9.1 11 5.5 20 MEAN CONCEN- TRATION (MG/L) SEPTEMBER 20 11 11 12 12 31 24 19 28 30 24 23 23 23 23 25 219 62 253 686 578 65 35 40 26 21 19 21 13 35 SEDIMENT DISCHARGE (TONS/DAY) .79 .25 .29 .27 .23 2.7 .92 .48 1.3 .97 .57 .54 .44 .42 .38 1.7 105 5.0 818 3980 2760 9.3 2.1 2.7 .84 .58 .54 .84 .19 3.9 1268.52 2506.9 7701.24 304 RIO GRANDB DB LOIZA BASIN 50055750 RIO GURABO BELOW EL MANGO, PR--Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT DATE MAY 1992 06. .. TIME 1155 DIS- CHARGE, INST. CUBIC FEET PER SECOND SEDI- MENT, SUS- PENDED (MG/L) SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) SED. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM SBD. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM SBD. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 1950 1780 9370 54 57 67 DATE MAY 1992 06. . . SBD. SUSP. FALL DIAM. PERCENT FINER THAN .016 MM SBD. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM SED. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 82 87 96 99 99.5 99.7 99.8 RIO GRANDB DB LOIZA BASIN 50055750 RIO OURABO BELOW EL MANGO--Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT 305 DATE OCT 1991 03... JAN 1992 06... MAR 07... 07... MAY 01... 06... 06... JUN 12... 16... 16... AUG 14... SEP 17... 21... TIME 1406 1015 1952 2057 2343 1130 1700 0916 0112 1847 1602 0406 1030 STREAM- FLOW, INSTAN- TANEOUS (CFS) 129 724 239 304 412 843 1390 635 411 428 325 350 156 SEDI- MENT, SUS- PENDED (MG/L) 170 166 786 199 799 1610 861 265 109 940 475 417 156 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 59 324 507 163 888 3670 3230 454 120 1080 417 395 66 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 97 95 68 95 94 94 97 99 93 87 92 88 92 306 RIO GRANDB DB LOIZA BASIN 50056400 RIO VALBNCIANO NEAR JUNCOS, PR LOCATION.--Lat 18°12'58", long 65°55'34", Hydrologic Unit 21010005, on left bank at Highway 919, 0.5 mi (0.8 km) upstream tram Quebrada Don Victor, 1.7 mi (2.7 km) upstream from Rio Ourabo and 1.0 ml (1.6 km) south of Ounces. DRAINAGE AREA.--16.4 ml* (42.5 km»). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—January 1971 to current year. GAGE.—Water-stage recorder. Elevation of gage is 320 ft (98 m), from topographic map. REMARKS.--Records fair except those for estimated daily discharges, which are poor. Minor diversion from public water supply tank, 0.5 ml upstream, during low flow. Gage-height and precipitation satellite telemetry at station. EXTREMES OUTSIDE PERIOD OF RECORD.--Approximate discharges (no stages were recorded) of major floods are as followsi Sept. 6, 1960, 37,100 ftVs (1,050 mVs), Oct. 9, 1970, 18,200 ft'/s (515 mVs). DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JON JUL ADO SEP 1 124 8.1 2 190 9.2 3 104 8.4 4 29 8.7 5 29 13 6 22 22 7 14 205 8 13 1340 9 14 206 10 16 133 11 38 44 12 16 31 13 15 26 14 13 20 15 18 17 16 17 17 17 23 16 18 16 15 19 17 15 20 12 15 21 e!2 20 22 e!5 52 23 ell 21 24 ell 113 25 10 29 26 9.1 20 27 7.4 72 28 6.9 26 29 9.5 24 30 16 20 31 8.0 TOTAL 855.9 2566.4 MEAN 27.6 85.5 MAX 190 1340 MIN 6.9 8.1 AC-FT 1700 5090 CFSM 1.68 5.22 IN. 1.94 5.82 e Estimated STATISTICS OF MONTHLY MEAN MEAN 81.9 94.3 MAX 293 461 (WY) 1986 1988 MIN 21.8 19.5 (WY) 1984 1990 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC- FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 17 17 22 36 19 16 15 15 14 14 13 14 13 13 12 14 13 11 11 13 16 11 11 11 10 11 11 10 10 10 14 437 14.1 36 10 867 .86 .99 DATA 59.1 550 1988 11.0 1990 FOR 13 11 9.7 9.4 1150 779 60 29 23 25 18 16 16 15 14 14 14 14 12 12 12 11 11 12 13 16 12 12 12 11 10 2386.1 77.0 1150 9.4 4730 4.69 5.41 FOR WATER 23.1 77.0 1992 11.4 1976 10 9.4 9.5 12 10 29 17 11 10 16 12 10 9.4 10 12 11 9.2 9.1 9.0 8.2 8.0 8.1 8.6 9.4 8.5 8.3 8.1 7.7 7.4 --- 307.9 10.6 29 7.4 611 .65 .70 YEARS 1971 17.7 47.9 1984 7.21 1974 6.9 7.8 7.9 9.2 12 16 9.1 9.6 7.5 7.1 6.4 6.4 6.5 6.8 9.3 6.5 10 10 7.0 11 7.9 8.2 6.9 6.5 5.7 6.7 6.3 5.9 5.0 4.9 5.0 242.0 7.81 16 4.9 480 .48 .55 - 1992 19.6 39.7 1973 7.01 1977 1991 CALENDAR YEAR 9203. 25. 1340 3. 3. 18260 1. 20. 35 11 5. 8 2 Nov 8 2 May 2 8 Apr 29 54 88 5 5.6 6.6 4.7 4.6 4.4 4.2 10 5.0 5.0 5.7 8.1 8.8 5.8 6.4 9.8 5.3 5.6 13 26 7.8 11 5.9 4.8 4.3 4.0 3.8 3.4 3.5 3.5 4.1 —— 200.7 6.69 26 3.4 398 .41 .46 6.2 42 7.2 5.2 4.5 8.9 8.4 6.0 4.7 4.6 6.4 7.7 4.4 4.3 6.8 34 11 6.7 5.7 14 11 5.5 678 458 103 801 56 33 25 23 20 2412.2 77.8 801 4.3 4780 4.74 5.47 115 87 34 27 30 28 42 83 84 80 109 157 138 95 64 43 40 29 25 34 204 50 47 27 22 20 19 17 15 15 —— 1780 59.3 204 15 3530 3.62 4.04 14 13 13 12 28 13 11 11 13 10 16 13 9.2 9.1 8.9 10 41 15 22 22 23 89 19 16 23 18 16 16 14 13 13 564.2 18.2 89 8.9 1120 1.11 1.28 13 25 21 17 236 50 84 46 26 31 24 29 23 29 25 20 21 17 15 20 39 16 20 80 20 18 18 16 18 15 33 1065 34.4 236 13 2110 2.09 2.42 21 16 19 15 14 47 27 18 48 17 15 13 13 12 12 47 125 33 201 970 509 56 54 36 30 25 26 27 22 22 2490 83.0 970 12 4940 5.06 5.65 , BY WATER YEAR (WY) 15.3 41.7 1985 5.82 1991 FOR 1992 15307. 41. 1340 3. 3. 9940 13. 30360 2. 34. 56 14 6. 54.9 268 1985 5.02 1990 WATER YEAR 4 8 Nov 8 4 Apr 27 8 Apr 24 Jan 5 09 Jan 5 55 72 4 50.3 188 1979 6.21 1977 46.1 163 1981 5.36 1974 WATER 50 121 17 9100 1 2 40000 25 1 36790 3 42 73 19 7 64.4 231 1979 15.5 1980 YEARS 1971 - .8 .1 Dec 8 .8 Jun 12 .6 May 19 Dec 8 .63 Dec 8 .4 Apr 21 .10 .07 .1 79.5 255 1979 10.8 1987 1992 1988 1990 1987 1990 1990 1987 1987 1988 RIO GRANDE DB LOIZA BASIN 50056400 RIO VALENCIANO NEAR JUNCOS, PR--Continued HATER QUALITY RECORDS PERIOD OF RECORD.--HATER YEARS AUGUST 1981 TO CURRENT YEAR 307 STRBAMFLOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCB TORE (CFS) (UMHOS) (DBG C) STRBAMFLOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCB TORE (CFS) (UMHOS) (DBG C) MAR. 16 1033 6.23 280 25.0 JUN. 03 1316 30.9 210 27.0 305 RI ° GRANDB DE LOIZA BASIN 50056400 RIO VALKNCIANO NEAR JUNCOS, PR--Continued WATER-QUALITY RECORDS PERIOD OP RECORDS.-- Water years 1983 to 1986 and water year 1989 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: October 1989 to September 1992. INSTRUMANTATION.-- Automatic sediment sampler. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATION: Maximum daily mean, 1,600 mg/L Oct. 06, 198S; Minii 1 mg/L several days. daily SEDIMENT LOADS: Maximum daily mean, 46,300 tons (42,000 tonnes) May 18, 1985; Minimum daily mean, 0.01 ton (0.01 tonne) several days. EXTREMES FOR WATER YEAR 1992.-- SBDIMBNT CONCENTRATION: Maximum daily mean, 945 mg/L Nov. 08, 1991; Minimum daily mean, 4 mg/L several days. SEDIMENT LOADS: Maximum daily mean, 10,500 tons (9,500 tonnes) Jan. 05, 1992; Minimum daily mean, 0.10 ton (0.09 tonne) several days. SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) OCTOBER 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 124 190 104 29 29 22 14 13 14 16 38 16 15 13 18 17 23 16 17 12 e!2 e!5 ell ell 10 9.1 7.4 6.9 9.5 16 8.0 163 240 143 53 56 46 31 23 18 36 74 47 35 24 20 36 48 41 35 28 18 10 10 14 25 34 40 41 40 41 30 76 138 50 4.3 5.5 3.0 1.2 .77 .69 1.7 11 2.1 1.3 .88 1.0 1.8 3.5 1.8 1.7 .91 e.53 e.40 e.30 e.43 .68 .81 .85 .78 1.1 2.0 .70 MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) (CFS) (MG/L) (TONS/DAY) NOVEMBER 8.1 9.2 8.4 8.7 13 22 205 1340 206 133 44 31 26 20 17 17 16 15 15 15 20 52 21 113 29 20 72 26 24 20 _._ 30 30 30 30 29 40 260 945 221 181 51 19 13 10 10 10 8 6 S 5 28 120 71 187 78 14 184 59 55 45 .67 .73 .70 .75 1.2 3.4 275 7590 168 83 6.6 1.6 .95 .56 .45 .42 .33 .24 .19 .20 2.5 20 4.1 88 7.2 .75 83 4.4 3.8 2.4 ___ DECEMBER 17 17 22 36 19 16 15 15 14 14 13 14 13 13 12 14 13 11 11 13 16 11 11 11 10 11 11 10 10 10 14 35 24 29 76 50 45 42 42 41 35 28 22 14 8 9 11 14 17 18 18 15 13 11 8 8 7 7 10 21 31 31 1.6 1.0 2.3 8.1 2.5 1.9 1.7 1.7 1.6 1.3 .97 .76 .48 .29 .29 .39 .45 .49 .54 .64 .67 .37 .31 .24 .22 .22 .20 .25 .55 .87 1.2 TOTAL 855.9 315.73 2566.4 8351.14 437 34.10 e Estimated RIO GRANDB DB LOIZA BASIN 50056400 RIO VALBNCIANO NEAR JUNCOS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 309 DAY MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) JANUARY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 13 11 9.7 9.4 1150 779 60 29 23 25 18 16 16 15 14 14 14 14 12 12 12 11 11 12 13 16 12 12 12 11 10 30 27 22 18 762 510 92 50 38 29 27 17 10 10 14 18 21 21 19 17 17 19 21 25 28 28 27 26 24 22 22 1.1 .75 .58 .45 10500 1520 17 4.1 2.S 1.9 1.3 .76 .42 .37 .51 .65 .80 .77 .59 .51 .51 .57 .60 .75 .94 1.2 .88 .88 .85 .66 .58 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) FEBRUARY 10 9.4 9.5 12 10 29 17 11 10 16 12 10 9.4 10 12 11 9.2 9.1 9.0 8.2 8.0 8.1 8.6 9.4 8.5 8.3 8.1 7.7 7.4 ___ 20 20 20 23 35 61 58 47 48 50 48 42 34 25 20 28 41 51 56 48 33 25 34 51 68 77 67 54 52 .52 .52 .52 .74 .95 6.0 3.0 1.4 1.3 2.2 1.6 1.1 .85 .64 .63 .81 .99 1.2 1.3 1.0 .68 .53 .77 1.3 1.6 1.6 1.4 1.1 1.0 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) MARCH 6.9 7.8 7.9 9.2 12 16 9.1 9.6 7.5 7.1 6.4 6.4 6.5 6.8 9.3 6.5 10 10 7.0 11 7.9 8.2 6.9 6.5 5.7 6.7 6.3 5.9 5.0 4.9 5.0 52 52 55 58 64 70 71 74 75 73 69 55 36 28 22 20 25 22 15 35 59 60 66 73 73 62 34 30 30 30 30 .98 1.1 1.3 1.6 2.1 3.2 1.8 1.9 1.6 1.4 1.2 .95 .63 .55 .56 .36 .84 .67 .28 1.4 1.3 1.3 1.3 1.3 1.1 1.2 .57 .49 .40 .40 .43 TOTAL 2386.1 12063.48 307.9 37.25 242.0 34.21 310 RIO GRANDB DB LOIZA BASIN 50056400 RIO VALENCIANO NBAR JUNCOS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) 5.6 6.6 4.7 4.6 4.4 4.2 10 5.0 5.0 5.7 8.1 8.8 5.8 6.4 9.8 5.3 5.6 13 26 7.8 11 5.9 4.8 4.3 4.0 3.8 3.4 3.5 3.5 4.1 --- APRIL 30 33 35 37 42 47 50 35 32 39 44 33 23 11 20 12 12 21 46 17 42 43 33 23 15 11 10 10 10 10 --- MEAN MEAN MEAN CONCBN- SEDIMENT MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARQB (CFS) (MG/L) (TONS/DAY) (CFS) (MG/L) (TONS/DAY) MAY .48 .54 .48 .45 .47 .57 1.4 .50 .48 .58 .99 .76 .40 .20 .61 .17 .19 3.2 6.0 .35 1.2 .65 .45 .26 .15 .11 .10 .10 .10 .11 --- 6.2 42 7.2 5.2 4.5 8.9 8.4 6.0 4.7 4.6 6.4 7.7 4.4 4.3 6.8 34 11 6.7 5.7 14 11 5.5 678 458 103 801 56 33 25 23 20 13 112 26 12 11 18 17 9 11 26 38 51 54 51 50 92 96 62 47 43 38 50 513 382 131 630 89 66 58 50 39 .28 17 .61 .16 .13 .51 .42 .14 .14 .32 .66 1.0 .63 .62 .89 15 3.5 1.1 .70 2.0 1.3 .73 4190 887 142 4750 14 6.1 4.0 3.1 2.1 JUNE 115 87 34 27 30 28 42 83 84 80 109 157 138 95 64 43 40 29 25 34 204 50 47 27 22 20 19 17 15 15 124 133 55 30 50 37 68 137 125 109 153 200 179 136 94 38 47 46 30 101 586 78 68 27 21 13 8 10 14 19 --- 155 45 5.8 2.3 4.7 2.6 9.4 49 36 33 56 136 101 39 17 4.3 5.9 3.6 1.9 9.1 533 12 11 2.0 1.2 .67 .40 .43 .58 .72 --- TOTAL 200.7 22.05 2412.2 10046.14 1780 1278.60 RIO GRANDB OB LOIZA BASIN 50056400 RIO VALBNCIANO NEAR JUNCOS, PR--Continued SBDIMBNT DISCHARGE, SOSPBNDBD (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 311 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) 1 2 3 4 S 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL YEAR 14 13 13 12 28 13 11 11 13 10 16 13 9.2 9.1 8.9 10 41 15 22 22 23 89 19 16 23 18 16 16 14 13 13 564.2 15307.4 JULY 20 19 18 17 55 37 25 16 7 4 24 24 13 5 7 14 65 30 38 40 41 119 27 19 42 21 9 6 5 5 4 —— MEAN MEAN CONCBN- SBDIMBNT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AUGUST .71 .62 .58 .51 4.7 1.3 .72 .46 .25 .12 1.4 .86 .33 .12 .18 .35 13 i:3 2.6 2.8 2.5 52 1.6 .90 2.7 1.0 .35 .28 .18 .18 .16 94.76 42463.12 13 25 21 17 236 SO 84 46 26 31 24 29 23 29 25 20 21 17 15 20 39 16 20 80 20 18 18 16 18 15 33 1065 4 39 37 15 514 77 116 60 40 55 40 39 15 39 32 26 41 39 35 34 134 64 36 109 25 14 9 8 8 8 54 —— .15 3.9 2.5 1.0 419 13 43 8.4 2.8 5.4 2.4 3.3 .84 4.1 2.4 1.3 2.4 1.8 1.5 3.1 19 2.9 2.1 41 1.5 .68 .44 .36 .35 .33 6.1 597.05 MEAN MEAN CONCEN- SBDIMBNT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) SEPTEMBER 21 16 19 15 14 47 27 18 48 17 15 13 13 12 12 47 125 33 201 970 509 56 54 36 30 25 26 27 22 22 2490 33 13 10 8 8 64 40 12 76 17 7 5 5 5 5 61 165 43 231 697 482 90 84 48 30 30 35 34 10 8 —— —— 2.2 .55 .50 .34 .32 15 3.8 .59 14 .77 .27 .20 .17 .16 .16 27 101 4.0 250 7690 1430 16 16 4.9 2.4 2.0 2.4 2.8 .60 .48 —— 9588.61 312 RIO GRANDB DB LOIZA BASIN SOOS6400 RIO VALBNCIANO NEAR JUNCOS, PR--Continued HATER QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT DATE TIME JAN 1992 05... 1937 05... 2132 SBD. SUSP. FALL DIAM. PERCENT FINER DATE THAN .016 MM JAN 1992 05... 57 OS... 42 DIS- CHARGE, INST. CUBIC FEET PER SECOND 8500 3800 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM 65 51 SEDI- MENT, SUS- PENDED (MQ/L) 5640 7610 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 90 63 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 129000 78100 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 97 71 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM 31 23 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 99 76 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM 41 28 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 99.8 85 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 46 33 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 99.9 96 RIO GRANDB DB LOIZA BASIN SOOS6400 RIO VALENCIANO NEAR JUNCOS, PR—Continued HATER QUALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 373 DATE NOV 1991 22. .. 24. .. 24... 27... 27... JAN 1992 05... 06. .. JUN 01... 02. .. 08. .. 12. .. 21. .. 21... SEP 21... TIME 1140 1331 1622 0924 0954 2252 1050 001S 005S 1300 0948 0320 0455 1100 STREAM- FLOW, INSTAN- TANEOUS (CFS) 33 408 205 263 235 2890 782 623 179 205 230 712 466 333 SEDI- MENT, SUS- PENDED (MG/L) 134 329 440 517 1190 2230 325 4120 391 122 833 1410 2310 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 12 362 243 367 755 17400 688 6940 189 68 517 2700 2910 31 28 96 99 100 98 99 91 96 65 95 92 99 99 99 96 314 RIO GRANDS DB LOIZA BASIN 50056900 Q0BBRADA MAMBY NEAR GURABO, PR LOCATION.--Lat 18<>14'57", long 65«56'44", Hydrologic Unit 21010005, at left downstream side of bridge on Highway 189, 1.9 mi (3.0 km) southeast of Qurabo plaza, and 2.1 mi (3.4 km) northwest of Juncos plaza. DRAINAGE AREA.--2.30 mi* (5.96 km*). HATER-DISCHARGE RECORDS PERIOD OP RECORD.--December 1983 to current year. GAGE.—Hater-stage recorder and crest-stage gage. Elevation of gage is 180 ft (55 m), from topographic REMARKS.--Records fair except those Cor estimated daily discharges, which are poor. DISCHARGE, CUBIC PBBT PER SECOND, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JDN JUL ADO SEP 1 .52 4.0 2 3.7 5.0 3 1.1 .94 4 .47 .68 5 .49 .64 6 .39 1.6 7 .31 24 8 .28 36 9 .29 5.4 10 .31 2.2 11 .29 1.4 12 .32 1.1 13 .30 1.1 14 .25 .98 IS .24 .94 16 .29 .90 17 .45 1.6 18 .53 .84 19 .65 .72 20 .72 .69 21 .67 1.1 22 .67 7.2 23 .67 1.7 24 .46 1.1 25 .40 .91 26 .44 .88 27 .47 6.0 28 .49 3.2 29 2.5 .87 30 12 .72 31 3.0 --- TOTAL 33.67 114.41 MEAN 1.09 3.81 MAX 12 36 MIN .24 .64 AC-FT 67 227 CFSM .47 1.66 IN. .54 1.85 e Estimated STATISTICS OF MONTHLY MEAN MEAN 7.24 7.81 MAX 24.4 21.6 (HY) 1986 1988 MIN 1.09 1.13 (HY) 1992 1990 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS .67 .66 .81 1.4 .97 .80 .84 .65 .70 .66 .73 .91 1.0 .75 .62 .64 .63 .56 .63 .87 .68 .49 .47 .48 .50 .50 .52 .51 .53 .52 .52 21.22 .68 1.4 .47 42 .30 .34 DATA 3.35 13.1 1988 .68 1992 FOR .53 .51 .49 .53 99 78 3.7 .91 .72 1.8 .45 .29 .25 .21 .19 .20 .17 .15 .16 .16 .16 .17 .16 .15 .17 .24 .19 .16 .15 .14 .15 190.26 6.14 99 .14 377 2.67 3.08 FOR HATER 1.77 6.14 1992 .57 1984 .17 .19 .26 .45 .21 .32 .29 .20 .21 .45 .30 .19 .17 .27 .21 .19 .17 .17 .18 .17 .16 .17 .20 .27 .29 .22 .20 .16 .15 --- 6.59 .23 .45 .15 13 .10 .11 YEARS 1984 1.58 3.89 1984 .23 1992 .14 .14 .17 .22 .55 .27 .25 .26 .24 .21 .21 .20 .19 .26 .47 .35 .36 .44 .40 .34 .35 .67 .34 .24 .21 .20 .19 .18 .18 .15 .13 8.51 .27 .67 .13 17 .12 .14 - 1992 1.25 3.57 1985 .27 1992 1991 CALENDAR YEAR 504. 1. 38 . . 1000 8. 1. . IS 38 May 11 21 Sep 26 27 Sep 3 60 IS 6 65 30 .14 .16 .16 .15 .15 .16 .22 .29 .32 .52 .39 .34 .31 .27 .29 .27 .61 .46 .43 .48 .41 .31 .32 .23 .19 .21 .25 .21 .20 .49 --- 8.94 .30 .61 .14 18 .13 .14 , BY HATER 1.18 3.55 1986 .30 1992 FOR 1992 814 2 99 3380 11 1620 13 2 9.0 11 1.9 .94 .73 3.9 2.5 1.2 .97 .89 1.0 1.1 1.2 1.1 1.0 1.7 1.8 15 7.9 5.8 5.9 2.8 52 48 16 93 21 8.7 4.3 2.6 1.7 326.63 10.5 93 .73 648 4.58 5.28 YEAR (HY) 5.52 19.7 1985 .34 1990 1.6 .79 .59 .47 .45 .74 1.2 1.3 .89 1.2 1.1 4.0 .89 .52 .32 .25 .23 .22 .21 .23 10 1.1 .56 .28 .22 .21 .24 .23 .25 .25 --- 30.54 1.02 10 .21 61 .44 .49 2.36 11.3 1987 .68 1985 HATER YEAR .27 .22 .13 .15 .78 .10 .97 .17 .7 .46 .19 Jan 5 Mar 31 Mar 30 May 26 May 26 Mar 31 .29 .34 .47 .53 .71 .66 .65 .71 .49 .40 .50 .81 .61 e.Sl e.43 e.38 e.74 e.28 e.39 e.41 e.60 el. 6 e.35 e.29 e.41 e.33 e.29 e.29 e.29 e.26 e.24 15.26 .49 1.6 .24 30 .21 .25 1.50 4.31 1988 .49 1992 e.23 e.4S e.38 e.31 e4.0 e.92 el. 5 e.80 e.48 e.54 e.44 e.52 e.42 e.52 e.4S .37 .30 .25 .28 .26 .84 .45 .33 .86 .31 .28 .24 .24 .22 .22 e.37 el.O e.38 e2.2 e.32 «1.62 e.28 e3.0 e.40 elO e.70 e8.0 e.30 e4.0 e.35 el.O el. 5 e.36 e.33 e.32 e.30 e.33 e.28 e.60 .90 .64 .54 .46 .48 .47 .40 --- 19.08 39.16 .62 1.31 4.0 .23 38 .27 .31 10 .22 78 .57 .63 2.82 4.18 11.0 14.2 1988 1989 .62 .63 1992 1986 HATER YEARS 1984 - 1992 3.41 5.39 1.23 343 .13 .15 3380 11.78 .10 2470 1.48 20.12 3.2 .83 .34 1988 1990 NOV 27 1987 Mar 31 1992 Mar 30 1992 May 26 1992 May 26 1992 Mar 31 1992 RIO GRANDB OB LOIZA BASIN 50056900 QOBBRAOA MAMBY NEAR GORABO, PR--Continued HATER QUALITY RECORDS PERIOD OF RECORD.--HATER YEARS MARCH 1984 TO CURRENT YEAR DATS TIME JAN. 13 1046 MAR. 24 1033 STREAM?LOW, INSTANTANBOOS (CFS) 0.26 0.28 SPECIFIC CON- DUCTANCE (UMHOS) 420 490 TEMPERA- TURE (DEQ C) 26.0 26.5 DATE TIME JUN. 04 0849 JUN. 23 1236 STRBAMFLOW, INSTANTANBOOS (CFS) 0.60 0.78 SPECIFIC CON- DUCTANCE (UMHOS) 490 400 315 TEMPERA- TURE (DBG C) 26.5 28.0 316 RIO GRANDS DE LOIZA BASIN 50057000 RIO GURABO AT GURABO, PR LOCATION.--Lat 18°15'30", long 65°58'OS*, Hydrologic Unit 21010005, on left bank, at bridge on Highway 181, 0.3 mi (0.5 km) east of Gurabo, and 4.5 mi (7.6 km) upstream from Rio Grande de Loiza. DRAINAGE AREA.--60.2 mi> (155.9 km1 ). WATER-DISCHARGE RECORDS PERIOD OF RECORD. --1958 (occasional low-flow measurements only), January to September 1959 (monthly only), October 1959 to current year. surements GAGE. — Water- stage recorder and crest-stage gage. Datum of gage is 131.58 ft (40.106 m) above mean sea level. Prior to Oct. 1, 1989 datum 5.0 ft (1.5 m) higher. REMARKS. --Records fair. Gage-height and precipitation satellite telemetry at station. EXTREMES OUTSIDE PERIOD OF RECORD .- -Approximate elevation to gage datum of the Aug. 4, 1945 flood, as pointed out by local residents, 26.6 ft (8.1 m) , datum then is use. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR MAY JON JUL AUG SEP 1 256 29 2 602 57 3 370 33 4 147 29 5 105 34 6 110 41 7 75 564 8 62 2740 9 58 501 10 63 336 11 60 114 12 40 73 13 34 61 14 34 49 15 33 41 16 37 39 17 40 38 18 28 33 19 30 29 20 23 27 21 21 30 22 26 174 23 20 54 24 18 140 25 19 76 26 16 41 27 15 98 28 14 62 29 36 47 30 53 43 31 39 —— TOTAL 2484 5633 MEAN 80.1 188 MAX 602 2740 MIN 14 27 AC-FT 4930 11170 CFSM 1.33 3.12 IN. 1.53 3.48 STATISTICS OF MONTHLY MEAN MEAN 210 208 MAX 1414 1045 (WY) 1971 1988 MIN 16.0 37.3 (WY) 1968 1974 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN- LOWEST DAILY MEAN ANNUAL SEVEN- DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 39 41 40 151 51 37 31 29 28 27 27 27 27 26 27 24 27 24 22 25 66 30 24 22 19 18 19 18 18 17 19 1000 32.3 151 17 1980 .54 .62 DATA 164 863 1988 10.7 1968 FOR 23 20 18 16 1940 2470 339 162 121 151 105 80 73 73 62 56 52 50 43 41 40 37 37 37 41 49 43 38 38 37 33 6325 204 2470 16 12550 3.39 3.91 FOR WATER 62.7 204 1992 16.4 1968 32 31 32 38 42 53 97 47 37 42 44 33 29 29 31 33 28 25 25 25 23 24 24 27 29 25 26 26 25 ___ --- 982 33.9 97 23 1950 .56 .61 YEARS 1960 46.4 131 1989 12.6 1968 23 22 26 21 46 35 29 70 34 23 19 17 16 16 27 26 19 31 26 21 27 24 24 20 17 16 16 18 17 17 17 760 24.5 70 16 1510 .41 .47 - 1992 40.1 97.5 1985 11.2 1965 1991 CALENDAR YEAR 22858. 62. 2740 7. 9. 45340 1. 14. 109 30 13 1 6 Nov 8 5 Aug 13 0 Aug 7 04 12 19 23 21 20 20 20 33 27 23 39 25 23 22 22 24 23 19 19 65 77 42 25 19 16 14 9.7 11 11 7.3 16 --- 735.0 24.5 77 7.3 1460 .41 .45 29 286 56 26 19 442 235 65 40 25 30 50 26 21 23 35 59 52 68 39 51 26 1010 1950 350 1810 318 157 101 79 93 7571 244 1950 19 15020 4.06 4.68 418 440 112 125 151 149 228 263 255 405 316 627 332 242 158 130 216 96 64 60 281 168 148 88 62 55 51 49 52 49 5790 193 627 49 11480 3.21 3.58 39 32 29 29 42 31 26 29 32 28 28 38 28 23 23 25 83 60 35 44 50 177 71 82 142 59 38 87 34 25 24 1493 48.2 177 23 2960 .80 .92 21 21 43 27 569 177 142 146 84 74 64 109 86 182 167 72 81 52 42 40 69 37 40 97 53 39 40 33 35 31 64 2737 88.3 569 21 5430 1.47 1.69 57 40 42 37 32 46 107 47 96 63 47 43 37 33 32 69 312 135 330 1520 1440 205 129 111 80 66 60 63 75 67 5421 181 1520 32 10750 3.00 3.35 , BY WATER YEAR (WY) 42.3 93.9 1985 15.8 1967 FOR 1992 40931 112 2740 7 12 10100 20 81190 1 25 189 39 19 155 746 1985 12.7 1990 WATER YEAR .0 Nov 8 .3 Apr 29 Apr 24 Jan 5 . 87 Jan 5 .86 .29 136 468 1970 16.8 1972 117 371 1979 20.9 1967 WATER 134 286 42 21100 4 5 74600 27 4 97140 2 30 215 50 19 177 610 1979 24.8 1967 YEARS 1960 .2 Sep .8 Sep .5 Sep Sep .70 Sep .5 Feb .23 .26 228 1225 1960 8.76 1967 - 1992 1979 1967 6 1960 26 1967 21 1967 6 1960 6 1960 21 1968 RIO GRANOB DB LOIZA BASIN 50057000 RIO 6URABO AT 6URA6O, PR--Continued WATER QUALITY RECORDS PERIOD OF RECORD.--WATER YEARS AUGUST 1981 TO CURRENT YEAR STRBAMFLOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCE TURB (CFS) (UHHOS) (DBG C) STRBAMFLOW, DATE TIME INSTANTANEOUS (CFS) MAR. 24 1209 JUN. 04 1042 19.6 74.1 320 280 27.0 28.0 JUN. 24 1017 JUL. 15 1148 85 22.1 317 SPECIFIC CON- TEMPERA- DUCTANCB TURE (UMHOS) (DBG C) 230 330 28.5 30.0 318 RIO GRANDE DE LOIZA BASIN 50057000 RIO GURABO AT GURABO--Continued HATER-QUALITY RECORDS PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: October 1983 to September 1992. INSTRUMENTATION.— USD-49 and automatic sediment sampler. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATION: Maximum daily mean, 9,220 mg/L Nov 27, 1987) Minimum daily mean, 4 mg/L January 19,20,21, 1992. SEDIMENT LOADS« Maximum daily mean, 686,000 ton* (622,340 tonnes) Nov 27, 1987; Minimum daily me 0.14 ton (0.13 tonne) April 24, 1990. EXTREMES FOR CURRENT YEAR.-- SEDIMENT CONCENTRATION: Maximum daily mean, 726 mg/L September 16, 1992) minimum daily mean, 4 mg/L January 19,20,21, 1992. SEDIMENT LOADS: Maximum daily mean, 6,560 ton* (5,950 tonnes) January 05, 1992) minimum daily 0.31 ton (0.28 tonne) January 04, 1992. SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) OCTOBER 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 256 602 370 147 105 110 75 62 58 63 60 40 34 34 33 37 40 28 30 23 21 26 20 18 19 16 15 14 36 53 39 178 415 232 97 79 82 59 48 49 56 42 32 28 24 18 16 16 18 18 18 16 25 17 13 13 13 13 13 29 44 34 139 767 272 40 23 25 12 8.0 7.7 9.6 6.8 3.5 2.7 2.2 1.5 1.5 1.7 1.3 1.3 1.2 .88 2.3 .88 .62 .64 .57 .53 .49 5.9 7.4 4.4 MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) (CFS) (MG/L) (TONS/DAY) NOVEMBER 29 57 33 29 34 41 564 2740 501 336 114 73 61 49 41 39 38 33 29 27 30 174 54 140 76 41 98 62 47 43 ___ 30 48 31 25 19 24 358 551 369 240 82 40 25 18 14 14 13 11 10 10 16 93 28 241 152 77 79 94 65 45 2.5 8.0 2.7 2.0 1.7 3.3 847 5670 603 252 28 8.0 4.0 2.3 1.6 1.5 1.3 1.0 .79 .73 1.6 61 4.2 128 34 9.0 29 16 8.2 5.2 DECEMBER 39 41 40 151 51 37 31 29 28 27 27 27 27 26 27 24 27 24 22 25 66 30 24 22 19 18 19 18 18 17 19 25 14 11 108 23 14 14 13 12 11 11 13 15 13 11 10 8 9 11 17 51 28 15 10 10 10 10 10 10 10 9 2.6 1.5 1.2 58 3.5 1.5 1.2 .99 .86 .76 .74 .96 1.1 .94 .77 .65 .60 .58 .66 1.3 9.7 2.4 1.0 .59 .53 .49 .51 .50 .47 .46 .46 TOTAL 2484 1351.61 5633 7737.62 1000 97.52 RIO GRANDE DB LOIZA BASIN 379 50057000 RIO GURABO AT GURABO--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN MEAN MEAN CONCBN- SEDIMENT MEAN CONCBN- SEDIMENT MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DAY (CPS) (MG/L) (TONS/DAY) (CPS) (MG/L) (TONS/DAY) (CPS) (MG/L) (TONS/DAY) JANUARY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 23 20 18 16 1940 2470 339 162 121 151 105 80 73 73 62 56 52 50 43 41 40 37 37 37 41 49 43 38 38 37 33 8 8 7 7 303 461 94 49 29 41 20 15 10 9 8 7 5 5 4 4 4 8 14 16 14 11 10 9 10 10 10 .52 .44 .37 .31 6560 4420 97 23 9.6 19 5.8 3.3 2.0 1.7 1.4 1.1 .77 .67 .55 .44 .48 .78 1.3 1.6 1.5 1.5 1.2 .92 .95 .97 .90 FEBRUARY 32 31 32 38 42 53 97 47 37 42 44 33 29 29 31 33 28 25 25 25 23 24 24 27 29 25 26 26 25 ___ 11 15 19 20 20 38 74 38 31 24 20 19 19 19 20 21 22 18 15 16 19 25 30 31 27 21 17 17 18 ___ .95 1.3 1.6 2.1 2.2 7.5 21 5.0 3.1 2.7 2.3 1.7 1.5 1.5 1.6 1.9 1.6 1.2 .96 1.0 1.2 1.6 1.9 2.2 2.0 1.5 1.1 1.1 1.2 ___ MARCH 23 22 26 21 46 35 29 70 34 23 19 17 16 16 27 26 19 31 26 21 27 24 24 20 17 16 16 18 17 17 17 18 18 18 18 22 25 24 54 29 21 20 20 20 19 25 23 20 19 19 20 20 20 19 18 15 12 13 16 18 18 18 1.1 1.0 1.2 1.1 2.6 2.4 1.9 11 2.9 1.3 1.0 .94 .85 .83 1.9 1.6 1.0 1.5 1.3 1.2 1.5 1.2 1.1 .95 .69 .53 .59 .79 .83 .81 .84 TOTAL 6325 11160.07 982 76.51 760 48.45 320 RIO GRANDS DB LOIZA BASIN 50057000 RIO GDRABO AT GDRABO--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 19 23 21 20 20 20 33 27 23 39 25 23 22 22 24 23 19 19 £5 77 42 25 19 16 14 9.7 11 11 7.3 16--- APRIL 16 15 17 19 20 21 28 25 21 692 28 28 28 29 30 31 31 28 54 73 55 51 47 40 35 36 36 38 40 48 ___ MEAN MEAN CONCBN- SEDIMENT MEAN DISCHARGE TRATION DISCHARGE DISCHARGE (CFS) (MG/L) (TONS/DAY) (CFS) MAY .83 .94 .99 1.0 1.1 1.1 2.6 1.9 1.3 100 1.9 1.8 1.7 1.7 2.0 2.0 1.5 1.4 12 17 6.4 3.6 2.4 1.7 1.3 .99 1.0 1.1 .82 2. a ___ 29 286 56 26 19 442 235 £5 40 25 30 50 26 21 23 35 59 52 £8 39 51 26 1010 1950 350 1810 318 157 101 79 93 £8 203 £4 47 30 281 170 33 19 17 18 41 27 21 21 29 46 76 £6 36 41 23 377 657 261 634 230 59 32 38 54 7.2 204 10 3.3 1.5 792 169 £.3 2.0 1.2 1.5 £.0 2.0 1.2 1.2 3.6 8.3 12 21 4.2 £.1 1.7 2200 4620 303 3230 216 28 8.5 8.0 23 418 440 112 125 151 149 228 263 255 405 316 £27 332 242 158 130 216 96 £4 £0 281 168 148 88 £2 55 51 49 52 49 MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) JUNE 418 440 112 125 151 149 228 263 255 405 316 £27 332 242 158 130 216 96 £4 £0 281 168 148 88 £2 55 51 49 52 49 300 294 84 93 123 107 177 196 187 344 245 389 236 175 109 97 159 73 52 49 200 120 122 71 47 41 36 31 27 25 £84 525 27 39 £2 44 191 163 142 461 224 984 246 119 49 44 111 20 9 8 196 £5 57 18 7 fi 5 4 3 3 .3 .3 .9 .0 .0 .2 .8 .3 TOTAL 735.0 17 6. 07 7571 11901.8 5790 4518.8 RIO GRANDS DB LOIZA BASIN 321 SOOS7000 RIO GORABO AT GORABO--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL YEAR 39 32 29 29 42 31 26 29 32 28 28 38 28 23 23 25 83 60 35 44 SO 177 71 82 142 59 38 87 34 25 24 1493 40931.0 JULY 25 26 29 31 37 37 40 40 38 36 35 38 39 38 40 42 69 48 30 36 40 131 89 66 109 57 55 72 S3 46 31 —— MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AUGUST 2.7 2.3 2.3 2.4 4.3 3.1 2.9 3.0 3.2 2.8 2.7 3.6 3.0 2.4 2.5 2.7 20 8.8 2.9 4.5 5.6 98 19 37 55 9.1 5.9 19 5.0 3.2 2.1 341.0 47052.15 21 21 43 27 569 177 142 146 84 74 64 109 86 182 167 72 81 52 42 40 69 37 40 97 53 39 40 33 35 31 64 2737 21 22 37 31 474 126 99 108 57 49 54 81 64 133 126 57 64 45 36 34 34 25 34 90 110 62 45 33 31 29 51 —— 1.3 1.3 5.2 2.6 1470 68 SO 46 14 11 9.7 25 16 113 74 11 IS 6.7 4.3 3.8 8.2 2.5 3.8 32 17 6.5 5.0 3.0 3.0 2.4 10 2041.3 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) SEPTEMBER 57 40 42 37 32 46 107 47 96 63 47 43 37 33 32 69 312 135 330 1520 1440 205 129 111 80 66 60 63 75 67 --- 5421 45 34 35 39 37 44 73 30 71 57 44 35 29 24 25 726 223 103 273 499 619 149 83 86 64 52 46 49 59 54 — - —— 7.2 3.8 3.8 4.0 3.1 7.2 27 3.8 20 9.8 5.5 4.0 2.9 2.1 2.0 69 233 40 609 3300 3030 91 30 27 14 9.2 7.4 8.6 16 11--- 7601.4 322 RIO GRANDS DB LOIZA BASIN 50057000 RIO GDRABO AT OORABO, PR--Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT DATE NOV 1991 08. .. JAN 1992 05... DIS- CHARGE, INST. CUBIC FEET TIME PER SECOND 1210 3900 2057 8360 SEDI- MENT, SUS- PENDED (MG/L) 1210 1180 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 12700 26600 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM 49 63 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM -- 69 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 53 78 DATE NOV 1991 08. . . JAN 1992 05... SBD. SUSP. FALL DIAM. PERCENT FINER THAN .016 MM 59 83 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM 76 83 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 93 99.7 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 95 99.8 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 97 99.9 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 99 99.9 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 100 100 RIO GRANDB DB LOIZA BASIN 50057000 RIO GORABO AT GURABO, PR--Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT 323 DATE NOV 1991 08... 08... 08... JAN 1992 05. .. 05. .. MAR 12... MAY 21... 24... JUN 01. .. 02... 11... AUG 05... 05. .. 05... 25... SEP 01. .. 19... 19... TIME 1040 1140 1626 1757 2257 0905 0918 1523 2126 0041 0828 0821 1036 1306 0711 0806 2106 2236 STREAM- FLOW, INSTAN- TANEOUS (CFS) 6500 4740 1170 2150 9540 17 59 764 643 1430 260 1990 1390 752 55 44 1346 1045 SEDI- MENT, SUS- PENDED (MG/L) 795 659 520 300 1050 41 114 202 422 447 275 2280 1100 560 143 1290 1570 860 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 14000 8440 1640 1740 27000 2 18 416 732 1720 193 12300 4120 1140 21 153 5700 2420 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 90 91 87 99 99 99 99 92 97 97 92 84 96 95 96 98 86 95 324 RIO GRANDE DE LOIZA BASIN 50057025 RIO GDRABO NEAR GDRABO, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°15'56", long 65<>59'04", at bridge on Highway 941, 1.2 mi (1.9 km) west gaging station 50057000, and 1.0 mi (1.6 km) northwest of Gurabo plaza. DRAINAGE AREA.--62.8 mi 1 (162.7 km1 ). PERIOD OF RECORD.--Hater year* 1979 to current year. WATER-QUALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 -northwest from DATE OCT 1991 08... DEC 06.. . FEB 1992 13.. . MAY 05... JUN 10... AUG 19.. . DATE OCT 1991 08.. . DEC 06.. . FEB 1992 13... MAY 05.. . JUN 10... ADG 19.. . DATE OCT 1991 08.. . DEC 06.. . FEB 1992 13... MAY 05... JUN 10.. . AUG 19. .. K = non- ideal TIME 0930 0905 0830 0850 0915 1245 HARD- NESS TOTAL (MG/L AS CACO3 ) 150 -- -- 130 -- 110 FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.20 -- -- 0.80 -- 0.20 count SPE- CIFIC CON- DUCT- ANCE (US/CM) 338 303 382 327 260 334 CALCIUM DIS- SOLVED (MG/L AS CA) 41 __ — 39 -- 24 SILICA, DIS- SOLVED (MG/L AS SI 02) 32 -- -- 24 -- 27 PH HATER WHOLE FIELD (STAND- ARD UNITS) 7.0 7.0 6.6 6.6 7.0 7.1 MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) 12 __ -- 8.5 -- 11 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 331 -- -- 204 -- 203 TEMPER- ATURE HATER (DEG C) 28.0 24.5 25.5 25.5 27.0 31.2 SODIUM, DIS- SOLVED (MG/L AS HA) 53 — — 14 — 25 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 9 36 10 30 145 17 TUR- BID- ITY (NTU) 1.2 23 0.60 13 130 9.3 SODIUM AD- SORP- TION RATIO 2 __ __ 0.5 -- 1 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 1.33 0.880 0.810 0.860 0.750 1.13 OXYGEN, DIS- SOLVED (MG/L) 1.6 2.8 2.1 1.8 4.2 2.5 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 6.9 -- — 4.4 -- 4.6 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.070 0.120 0.100 0.140 0.050 0.070 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 20 42 26 22 60 32 ALKA- LINITY HAT WH TOT FET FIELD MG/L AS CAC03 110 100 130 93 80 80 NITRO- GEN, N02+N03 TOTAL (MG/L AS N) 1.40 1.00 0.910 1.00 0.800 1.20 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 62 28 15 29 33 21 SULFIDE TOTAL (MG/L AS S) <0.5 — — <0.5 — — — NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.150 0.370 0.710 0.480 0.610 0.270 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 2900 2000 K660 2100 30000 5800 SULFATE DIS- SOLVED (MG/L AS SO4) 57 -- -- 24 -- 18 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.65 0.73 0.59 0.52 0.69 0.53 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 1000 K820 260 650 21000 200 CHLO- RIDE, DIS- SOLVED (MG/L AS CL) 63 — — 34 — 29 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.80 1.1 1.3 1.0 1.3 0.80 RIO GRANDB DB LOIZA BASIN 50057025 RIO GURABO NEAR GURABO, PR—Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 325 DATE OCT 1991 08. . . DEC 06. . . FEB 1992 13. .. MAY 05.. . JUN 10.. . AOG 19.. . NITRO- GEN, TOTAL (MG/L AS N) 2.2 2.1 2.2 2.0 2.1 2.0 NITRO- GEN, TOTAL (MG/L AS N03) 9.7 9.3 9.8 8.9 9.3 8.9 PHOS- PHORUS ARSENIC TOTAL TOTAL (MG/L (OG/L AS P) AS AS) 0.460 <1 0.520 0.550 0.480 2 0.460 0.510 BARIUM, TOTAL RECOV- ERABLE (OG/L AS BA) <100 -- -- <100 -- -- BORON, TOTAL RECOV- ERABLE (OG/L AS B) 80 — -- 50 -- -- CADMIUM TOTAL RECOV- ERABLE (OG/L AS CD) <1 -- -- <1 -- -- CHRO- MIUM, TOTAL RECOV- ERABLE (OG/L AS CR) 7 -- -- 2 -- -- COPPER, TOTAL RECOV- ERABLE (OG/L AS CU) 30 -- -- 10 -- -- IRON, TOTAL RECOV- ERABLE (UG/L AS FE) 500 -- -- 660 -- -- DATE OCT 1991 08.. . DEC 06.. . FEB 1992 13.. . MAY 05. .. JUN 10. .. AUG 19.. . LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) 3 -- -- 3 -- -- MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) 210 -- -- 460 -- -- MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) 0.10 -- -- <0.10 -- -- SILVER, SELB- TOTAL NIUM, RECOV- TOTAL ERABLE (UG/L (UG/L AS SB) AS AG) <1 2 __ __ <1 <1 __ — ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) 30 -- -- <10 -- — CYANIDE TOTAL PHENOLS (MG/L TOTAL AS CN) (UG/L) 0.010 3 __ __ •cO.010 3 __ __ MBTHY- LBNB BLUB ACTIVE SUB- STANCE (MG/L) 0.10 -- -- 0.07 -- -- 326 RIO GRANDB DB LOIZA BASIN 50058350 RIO CANAS AT RIO CANAS, PR LOCATION.--Lat 18°17'41", long 66°02'44", Hydrologic Unit 21010005, at right bank, off road 798, upstream side of bridge on Highway 52, .5 mi (.8 km ) northeast from Bscuela Segunda Unidad de Francisco Valdes, and .8 mi (1.3 km) north of La Barra. DRAINAGE AREA.--7.53 mi* (19.50 km1 ). HATBR-DISCHARGB RECORDS PERIOD OF RECORD.--March 1990 to current year. GAGB.—Hater-stage recorder and crest-stage gage. Elevation of gage is 164 ft (50 m), from topographic map. REMARKS.—Records fair. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC PBBT PER SECOND, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SBP 1 5.5 11 2 .9 7.5 3 .5 5.4 4 .6 4.8 5 .8 4.6 6 .4 4.4 7 .1 9.5 8 .1 16 9 .1 8.4 10 .1 5.2 11 4.0 .5 12 3.8 .4 13 3.8 .8 14 3.8 .3 15 3.9 .3 16 4.0 .7 17 3.8 .3 18 4.9 .2 19 3.9 3.9 20 3.7 3.9 21 3.7 16 22 6.2 17 23 4.2 32 24 3.7 15 25 3.7 7.3 26 3.7 7.1 27 3.6 8.1 28 3.5 6.9 29 5.8 6.2 30 15 5.9 31 4.8 —— TOTAL 142.6 241.6 MEAN 4.60 8.05 MAX 15 32 MIN 3.5 3.9 AC-FT 283 479 CFSM .61 1.07 IN. .70 1.19 STATISTICS OP MONTHLY MEAN MEAN 22.0 7.61 MAX 39.4 8.05 (WY) 1991 1992 MIN 4.60 7.18 (WY) 1992 1991 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 5.9 5.9 11 7.9 6.4 6.0 5.6 5.5 5.7 5.5 5.3 5.3 5.1 5.6 5.5 5.0 5.0 5.0 5.0 12 6.1 5.0 4.8 4.7 4.7 4.8 5.4 4.9 4.9 4.8 5.0 179.3 5.78 12 4.7 356 .77 .89 DATA 8.89 12.0 1991 5.78 1992 FOR 5.0 5.0 4.7 4.7 241 145 32 20 15 29 16 13 16 11 12 31 25 13 11 11 9.8 9.7 9.1 9.9 9.5 9.4 8.4 8.6 9.1 8.4 8.4 760.7 24.5 241 4.7 1510 3.26 3.76 8.4 8.4 8.4 8.4 7.8 7.8 7.8 7.8 7.8 8.9 7.7 6.7 6.7 8.5 9.0 7.8 7.2 7.2 7.2 7.2 7.4 7.6 7.8 7.8 7.8 7.8 12 7.2 7.2 ___ --- 229.3 7.91 12 6.7 455 1.05 1.13 FOR HATER YEARS 1990 15.7 24.5 1992 6.76 1991 10.5 13.2 1991 7.91 1992 6.7 6.7 6.6 6.2 6.2 6.1 5.7 5.7 5.7 5.7 5.7 5.7 5.7 5.6 5.8 5.3 8.2 7.1 5.8 5.3 5.4 5.5 .8 .5 .3 .5 .5 9.8 8.1 5.0 4.5 182.4 5.88 9.8 4.3 362 .78 .90 - 1992 5.84 5.88 1992 5.80 1991 1991 CALENDAR YEAR 2896.9 7.94 140 2.9 3.3 5750 1.05 14.31 11 5.2 3.8 Feb 5 May 4 Apr 23 4.5 4.5 4.5 4.4 3.6 3.1 6.6 4.6 4.1 4.1 4.1 3.6 3.6 3.7 3.5 3.8 4.2 4.0 4.7 5.7 3.5 3.5 3.5 3.5 3.2 2.9 2.7 2.7 8.0 16 ... 134.4 4.48 16 2.7 267 .59 .66 58 55 12 7.7 6.2 11 6.4 4.5 5.2 4.3 3.5 3.0 2.7 2.7 2.5 49 6.5 6.7 4.5 4.5 3.8 3.2 50 52 20 134 39 15 14 8.9 7.3 603.1 19.5 134 2.5 1200 2.58 2.98 10 7.0 5.9 17 6.2 5.6 27 22 86 18 8.9 10 6.3 5.4 4.9 4.9 4.9 5.2 5.0 4.8 21 5.7 4.9 4.9 4.8 4.1 4.1 4.1 3.9 3.8 326.3 10.9 86 3.8 647 1.44 1.61 3.8 5.3 4.9 4.9 3.5 3.5 3.2 4.5 5.3 4.9 5.7 4.5 4.9 5.3 5.3 4.5 4.1 4.1 3.5 3.2 3.2 3.2 3.2 4.5 3.2 2.4 2.2 2.2 2.4 2.4 3.5 121.3 3.91 5.7 2.2 241 .52 .60 3.8 2.9 3.5 11 68 15 4.6 3.5 266 33 17 8.8 6.3 15 6.8 4.5 4.0 3.5 3.5 3.5 11 4.6 3.4 3.2 3.0 3.1 3.2 2.9 2.7 5.0 7.7 534.0 17.2 266 2.7 1060 2.29 2.64 5.7 5.1 5.1 9.4 12 61 65 19 12 9.7 9.1 9.4 24 7.3 4.4 5.9 18 5.1 20 22 25 5.4 3.6 3.1 2.9 2.9 2.8 2.5 2.4 6.6 386.4 12.9 65 2.4 766 1.71 1.91 , BY HATER YEAR (WY) 4.20 4.57 1991 3.53 1990 FOR 1992 3841 10 266 2 2 1700 16 7620 1 18 16 5 3 10.8 19.5 1992 3.32 1990 WATER YEAR .4 .5 Aug 9 .2 Jul 27 .6 Jul 25 Aug 9 .46 Aug 9 .39 .98 .4 .5 7.77 10.9 1992 4.06 1990 7.84 16.2 1991 3.40 1990 HATER 10 11 10 292 2 2 3830 20 7910 1 19 14 5 3 9.56 17.2 1992 4.36 1990 YEARS 1990 .9 .4 .5 Oct .2 Jul .6 Jul Oct .55 Oct .45 .71 .0 .3 8.29 12.9 1992 5.62 1991 - 1992 1991 1992 17 1990 27 1992 25 1992 17 1990 17 1990 RIO GRANDB DB LOIZA BASIN 50058350 RIO CANAS AT RIO CANAS, PR--Continued WATER QUALITY RECORDS PERIOD OP RECORD.-- OCTOBER 1990 TO CURRENT YEAR STRBAMFLON, DATE TIME INSTANTANEOUS (CPS) MAR. 17 1321 MAY 22 1236 10.3 3.21 SPECIFIC CON- DUCTANCE (UMHOS) 340 310 TEMPERA- TURE (DBG C) 24.0 27.5 STRBAMFLOW, SPECIFIC CON- DATE TIME INSTANTANEOUS DUCTANCB JUN. 11 1153 (CFS) 7.60 (UMHOS) 310 327 TEMPERA- TURE (DBG C) 27.0 328 RIO GRANDB DB LOIZA BASIN 50058350 RIO CANAS AT RIO CANAS, PR—Continued HATER-QUALITY RECORDS PERIOD OF RECORDS.-- Hater years 1990 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGES March 1990 to September 1992. INSTRUMENTATION.— Automatic sediment sampler. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATION: Maximum daily mean, 1,770 mg/L Jan. OS, 1992; Minimum daily mean, 1 mg/L September 11,1991 SEDIMENT LOADS: Maximum daily mean, 4,920 tons (4,460 tonnes) October 17, 1990; Minimum daily mean, 0.02 ton (0.02 tonne) several days. EXTREMES FOR CURRENT YEAR.-- SEDIMENT CONCENTRATION: Maximum daily mean, 1,770 mg/L JAN. OS, 1992; Minimum daily mean, 3 mg/L several days. SEDIMENT LOADS: Maximum daily mean, 4,230 tons (3,840 tonnes) Jan. OS, 1992; Minimum daily mean, 0.02 ton (0.02 tonne) several days. SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) OCTOBER 1 2 3 4 S 6 7 8 9 10 11 12 13 14 IS 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL S.S .9 .5 .6 .8 .4 .1 .1 .1 .1 4.0 3.8 3.8 3.8 3.9 4.0 3.8 4.9 3.9 3.7 3.7 6.2 4.2 3.7 3.7 3.7 3.6 3.5 5.8 15 4.8 142.6 31 24 17 9 7 7 7 7 S 4 4 8 15 21 18 14 10 14 12 17 22 29 15 18 14 12 9 6 12 81 12 ___ .49 .31 .21 .11 .09 .08 .08 .07 .06 .05 .05 .09 .15 .21 .19 .15 .11 .23 .12 .16 .21 .80 .17 .17 .13 .11 .09 .06 .31 19 .17 24.23 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) NOVEMBER 11 7.5 5.4 4.8 4.6 4.4 9.5 16 8.4 5.2 .5 .4 .8 .3 .3 .7 .3 .2 3.9 3.9 16 17 32 15 7.3 7.1 8.1 6.9 6.2 5.9 61 25 17 23 30 32 36 60 31 13 7 4 4 3 3 4 7 9 11 11 90 254 169 64 15 8 14 11 11 10 5.7 .57 .24 .29 .38 .39 1.3 3.8 .85 .18 .09 .05 .05 .04 .04 .06 .09 .10 .12 .11 20 29 127 4.2 .31 .16 .31 .21 .19 .16 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) DECEMBER 241.6 195.99 S.9 S.9 11 7.9 6.4 6.0 S.6 S.5 5.7 5.5 5.3 S.3 5.1 5.6 5.5 5.0 S.O 5.0 S.O 12 6.1 S.O 4.8 4.7 4.7 4.8 5.4 4.9 4.9 4.8 S.O 179.3 9 8 35 32 26 25 25 25 SO 13 10 10 10 11 13 13 13 16 19 50 20 11 9 7 7 7 8 14 20 26 31 .15 .12 1.8 .69 .45 .40 .38 .38 .76 .20 .13 .14 .14 .16 .17 .18 .18 .20 .24 3.6 .36 .14 .11 .09 .08 .09 .12 .18 .26 .33 .41 12.64 RIO GRANDB DB LOIZA BASIN 50058350 RIO CANAS AT RIO CANAS, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) 329 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CPS) 5.0 5.0 4.7 4.7 241 145 32 20 15 29 16 13 16 11 12 31 25 13 11 11 9.8 9.7 9.1 9.9 9.5 9.4 8.4 8.6 9.1 8.4 8.4 MEAN CONCEN- TRATION (MG/L) JANUARY 24 15 7 5 1700 1170 99 50 44 37 16 9 8 7 5 602 413 95 37 19 10 11 16 17 16 15 15 16 15 12 8 SEDIMENT DISCHARGE (TONS/DAY) .32 .19 .08 .06 4230 797 9.8 2.7 1.8 2.8 .70 .31 .38 .22 .15 192 35 4.6 1.1 .54 .28 .28 .40 .44 .42 .37 .35 .39 .35 .27 .18 FEBRUARY 8.4 8.4 8.4 8.4 7.8 7.8 7.8 7.8 7.8 8.9 7.7 6.7 6.7 8.5 9.0 7.8 7.2 7.2 7.2 7.2 7.4 7.6 7.8 7.8 7.8 7.8 12 7.2 7.2 8 10 10 11 13 13 13 13 13 13 14 14 15 40 8 8 9 11 11 9 8 8 7 6 6 7 28 7 7 .19 .21 .23 .25 .28 .27 .28 .28 .28 .30 .29 .26 .28 1.0 .19 .18 .18 .22 .22 .18 .16 .16 .IS .13 .13 .15 1.7 .14 .14 MEAN DISCHARGE (CPS) 6.7 6.7 6.6 6.2 6.2 6.1 5.7 5.7 5.7 5.7 5.7 5.7 5.7 5.6 5.8 5.3 8.2 7.1 5.8 5.3 5.4 5.5 .8 .5 .3 .5 .5 9.8 8.1 5.0 4.5 MEAN CONCEN- TRATION (MG/L) MARCH 7 6 5 7 10 12 10 8 6 4 3 3 3 3 3 3 16 10 10 8 7 6 5 9 10 10 10 3 24 5 7 SEDIMENT DISCHARGE (TONS/ DAY) .13 .11 .10 .12 .17 .20 .16 .13 .09 .07 .05 .05 .04 .04 .04 .04 .47 .19 .15 .13 .11 .09 .07 .10 .12 .12 .11 .32 .61 .07 .08 TOTAL 760.7 5283.48 229.3 8.43 182.4 4.28 330 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 RIO GRANDB DB LOIZA BASIN 50058350 RIO CANAS AT RIO CANAS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) APRIL 4.5 4.5 4.5 4.4 3.6 3.1 6.6 4.6 4.1 4.1 4.1 3.6 3.6 3.7 3.5 3.8 4.2 4.0 4.7 5.7 3.5 3.5 3.5 3.5 3.2 2.9 2.7 2.7 8.0 16 7 7 7 7 7 6 34 28 22 15 15 13 13 12 8 11 38 18 7 5 4 6 8 11 17 23 29 34 56 111 .08 .08 .08 .08 .06 .04 .67 .39 .25 .16 .16 .13 .13 .12 .08 .11 .42 .19 .08 .08 .04 .05 .07 .10 .14 .18 .22 .24 3.6 7.3 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MAY 58 55 12 7.7 6.2 11 6.4 4.5 5.2 4.3 3.5 3.0 2.7 2.7 2.5 49 6.5 6.7 4.5 4.5 3.8 3.2 50 52 20 134 39 15 14 8.9 7.3 459 358 41 20 8 33 12 5 5 6 7 6 4 4 5 367 21 10 7 6 5 5 370 355 78 1060 250 32 45 19 10 321 123 1.5 .40 .14 1.3 .22 .06 .08 .08 .07 .05 .03 .03 .04 277 .40 .18 .09 .08 .05 .04 170 113 8.1 1490 33 1.6 3.4 .50 .19 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) JUNE 10 7.0 5.9 17 6.2 5.6 27 22 86 18 8.9 10 6.3 5.4 4.9 4.9 4.9 5.2 5.0 4.8 21 5.7 4.9 4.9 4.8 4.1 4.1 4.1 3.9 3.8 27 18 14 108 15 12 161 105 708 80 20 34 14 8 8 13 17 20 20 20 98 18 14 10 8 7 6 5 4 4 1.3 .37 .22 14 .26 .18 43 17 487 5.0 .53 1.9 .24 .13 .09 .17 .23 .28 .26 .25 12 .29 .19 .13 .10 .08 .07 .06 .05 .04 TOTAL 134.4 15.33 603.1 2545.63 326.3 585.42 RIO GRANDB DB LOIZA BASIN 50058350 RIO CANAS AT RIO CANAS, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 331 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL YEAR 3.8 5.3 4:9 4.9 3.5 3.5 3.2 4.5 5.3 4.9 5.7 4.5 4.9 5.3 5.3 4.5 4.1 4.1 3.5 3.2 3.2 3.2 3.2 4.5 3.2 2.4 2.2 2.2 2.4 2.4 3.5 121.3 3841.4 JULY 4 i 5 6 8 8 8 8 6 4 5 6 6 7 7 7 7 8 7 6 6 6 6 8 11 12 13 13 12 10 10 —— MEAN DISCHARGE (CFS) MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) AUGUST .04 .06 .08 .09 .08 .08 .07 .10 .09 .06 .08 .08 .08 .10 .10 .09 .08 .08 .07 .06 .06 .06 .05 .10 .10 .08 .08 .08 .08 .07 .09 2.42 13345.89 3.8 2.9 3.5 11 68 15 4.6 3.5 266 33 17 8.8 6.3 15 6.8 4.5 4.0 3.5 3.5 3.5 11 4.6 3.4 3.2 3.0 3.1 3.2 2.9 2.7 5.0 7.7 534.0 8 7 5 42 467 59 11 8 1550 132 62 19 6 59 16 9 7 15 6 4 46 11 6 6 7 7 8 9 9 16 20 —— .08 .06 .05 3.9 153 5.5 .15 .08 3990 21 3.9 .56 .10 5.7 .35 .10 .08 .14 .05 .04 5.7 .15 .06 .06 .06 .07 .07 .07 .07 .49 .53 4192.17 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) SEPTEMBER 5.7 5.1 5.1 9.4 12 61 65 19 12 9.7 9.1 9.4 24 7.3 4.4 5.9 18 5.1 20 22 25 5.4 3.6 3.1 2.9 2.9 2.8 2.5 2.4 6.6 16 13 7 27 41 455 500 77 28 18 15 11 136 30 10 9 76 20 106 109 117 12 19 22 19 15 9 4 4 24 .66 .18 .11 1.3 2.2 195 190 5.6 .94 .48 .36 .25 26 .90 .14 .14 8.3 .31 14 15 12 .18 .18 .18 .15 .11 .06 .02 .02 1.1 386.4 475.87 332 RIO GRANDB DB LOIZA BASIN 50058350 RIO CANAS AT CANAS, PR—Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT DATE TIME DIS- CHARGE, INST. CUBIC FEET PER SECOND SEDI- MENT, SUS- PENDED (MO/L) SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) SBD. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM SBD. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM SBD. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM JAN 1992 16... 2100 139 2550 957 31 41 DATE JAN 1992 16. .. SBD. SUSP. FALL DIAM. PERCENT FINER THAN 016 MM SBD. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 57 65 90 97 99 99.8 99.9 RIO GRANDB DB LOIZA BASIN 50058350 RIO CANAS AT CANAS, PR—Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT 333 DATE NOV 1991 08... 27... DEC 09... JAN 1992 07... 16... MAY 18... SEP 06... 07. .. 30. .. TIME 1539 1250 1207 1325 2200 0757 1300 1345 1712 STREAM- FLOW, INSTAN- TANEOUS (CFS) 12 9.6 5.5 30 174 7.8 284 152 21 SEDI- MENT, SUS- PENDED (MG/L) 182 224 95 81 1320 44 3010 874 127 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 6 6 1.4 6.6 619 1 2310 358 7 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 91 99 94 98 94 98 94 89 89 334 RIO GRANDS OB LOIZA BASIN 50059000 LAQO LOIZA AT OAMSITB, PR LOCATION.—Lat 18°19'49", long 66°01'00", Hydrologic Unit 21010005, at punpsite at damaite, and 1.9 ml (3.1 km) south of Trujillo Alto plaza. ORANAIQB ARBA.--208 mi' (539 km» ) • ELEVATION RECORDS PERIOD OF RBCORO.—December 1987 to current year. GAQB.—Water-stage recorder. Datum of gage is mean aea level. REMARKS.—Lake is formed by Loiza Dam, a concrete structure completed in 1954. Useable capacity of impoundment is 30,000 acre-ft (37.0 hm?). Out flow from lake is controlled by five elide gates in powerplant and pump intake structure, four sluice gates, and concrete spillway with eight radial gates. Lake is used for municipal water supply and intermittent power generation. Gage-height satellite telemetry at station. EXTREMES OBSERVED FOR PERIOD OF RECORD.—Maxio 125.86 ft (38.36 m), June 12, 1988. elevation 147.42 ft (44.93 m), Sept. 18, 1989; minimum elevation, EXTREMES OBSERVED FOR CURRENT YEAR.—Maximum elevation 135.30 ft (41.24 m), Sept. 20; minimum elevation, 127.15 ft (38.76 m). May 1. Capacity Table (based on data from Puerto Rico Electric Power Authority) Elevation, in feet 98.4 111.5 120.4 Contents in acre-feet 5,000 8,900 13,000 Elevation, in feet 128.6 137.8 147.6 Contents in acre-feet 18,000 26,000 35,000 ELEVATION (FEET NGVD), HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY OBSERVATION AT 24tOO VALUES DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN MAX MIN OCT 134.36 134.42 133.36 133.78 134.08 134.34 134.44 134.46 134.48 134.56 134.60 134.68 133.82 133.82 133.84 133.86 133.92 133.96 133.96 133.90 133.84 134.08 134.12 134.06 134.00 NOV 133.86 134.04 134.06 134.04 134.10 134.30 134.16 133.14 134.34 134.20 134.46 134.48 134.56 134.42 134.54 134.74 134.10 134.22 134.28 134.34 133.22 133.12 133.74 134.30 134.33 DEC 134.70 133.48 133.84 134.46 134.72 134.12 134.24 134.36 134.46 134.52 134.56 134.64 134.72 134.88 134.37 134.40 134.44 134.44 134.42 134.60 134.38 134.42 134.44 134.42 134.38 JAN 134.22 134.20 134.16 134.10 133.24 133.86 134.50 134.24 134.18 134.08 134.04 134.42 134.80 134.14 134.38 134.26 134.80 134.26 134.40 134.48 134.58 134.64 134.70 134.76 134.50 FBB 134.74 134.70 134.70 134.72 134.74 134.82 134.52 134.56 134.56 134.70 134.74 134.71 134.66 134.64 134.64 134.60 134.54 134.44 134.38 134.32 134.24 134.15 134.09 134.04 133.98 MAR 133.59 133.46 133.36 133.28 133.24 133.18 133.10 133.24 133.16 133.04 132.90 132.78 132.58 132.46 132.38 132.26 132.22 132.24 132.18 132.12 132.04 131.93 131.82 131.68 131.50 APR 130.48 130.32 130.14 129.94 129.78 129.52 129.44 129.30 129.10 128.94 128.80 128.72 128.86 128.78 128.78 128.68 128.52 128.36 128.54 129.00 129.08 128.98 128.84 128.64 128.41 MAY 127.70 129.16 129.22 129.08 128.90 129.96 130.62 130.64 130.58 130.42 130.28 130.26 130.19 130.02 129.98 133.04 134.04 134.40 134.00 134.22 134.36 134.34 131.91 134.83 133.13 JUN 135.01 134.69 133.54 133.80 134.68 134.41 133.87 134.75 133.78 134.02 134.22 134.64 133.94 134.04 133.32 134.00 133.48 134.22 134.60 134.14 133.52 134.34 134.84 133.92 134.14 JUL 134.74 134.76 134.76 134.74 134.48 134.52 134.50 134.62 134.12 134.14 134.40 134.52 134.54 134.54 134.56 134.60 134.32 134.48 134.58 134.82 134.28 133.58 133.83 134.05 134.55 AUQ 133.62 133.64 133.76 133.97 133.23 134.15 133.80 134.07 134.05 134.07 133.40 133.84 134.05 134.59 133.40 133.56 133.72 133.80 133.82 133.85 133.92 133.92 133.90 134.08 134.10 SEP 134.21 134.19 134.25 134.33 134.51 133.49 134.73 133.37 134.05 134.16 134.18 134.16 134.14 134.08 134.02 134.18 133.34 133.74 133.18 133.90 133.17 133.69 133.33 133.79 133.37 133.90 133.80 133.66 134.20 133.56 133.66 134.58 134.60 134.46 134.22 134.48 134.32 134.30 134.26 134.22 134.16 134.18 134.62 134.66 134.70 134.74 134.74 134.74 133.92 133.88 133.80 133.70 _._ 131.33 131.16 131.06 130.96 130.80 130.60 128.17 127.94 127.68 127.48 127.34 134.54 134.41 134.36 134.73 134.49 134.10 134.32 134.46 134.58 134.66 134.72 —— 134.72 134.82 133.53 133.55 133.53 133.66 134.07 134.08 134.05 134.05 134.05 134.15 133.59 133.77 133.09 133.27 133.45 —— 134.05 134.68 133.36 134.18 134.74 133.12 134.38 134.88 133.48 134.39 134.80 133.24 134.42 134.82 133.70 132.31 133.59 130.60 128.89 130.48 127.34 132.00 134.83 127.70 134.22 135.01 133.32 134.35 134.82 133.53 133.90 134.59 133.23 133.82 134.73 133.09 RIO GRANDS DB LOIZA BASIN 50059000 LAGO LOIZA AT DAMSITS, PR--Continued HATER-QUALITY RECORDS PERIOD OF RECORD.--Hater years 1974 to current year. HATER-QUALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 335 DATE OCT 1991 15... DEC 04... FBB 1992 12... MAY 01... JUN 12... AUG 10.. . TIMS 1115 1140 1140 1320 0920 1345 SPE- CIFIC CON- DUCT- ANCE (US/CM) 350 240 294 368 186 298 PH HATER WHOLE FIELD TEMPER- OXYGEN, (STAND- ATURB DIS- ARD HATER SOLVED UNITS) (DBG C) (MG/L) 7.2 6.9 6.8 7.0 7.0 7.4 26.0 26.0 27.5 29.0 28.5 28.5 2.8 4.1 2.3 4.4 1.2 1.8 OXYGEN, OXYGEN DIS- DEMAND, SOLVED CHEM- (PBR- ICAL CENT (HIGH SATUR- LEVEL) ATION) (MG/L) 34 48 30 56 32 39 20 28 13 24 15 27 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 56 23 10 60 90 K600 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 46 43 10 21 78 1100 ALKA- LINITY HAT WH TOT PET FIELD MG/L AS CAC03 77 72 97 100 55 60 DATE OCT 1991 15... DEC 04.. . FBB 1992 12... MAY 01... JUN 12... AUG 10... RESIDUE TOTAL AT 105 SULPIDB DBG. C, TOTAL (MG/L AS S) <O.S <0.5 SUS- PENDED (MG/L) 5 16 14 7 43 54 NITRO- NITRO- GEN, GEN, NITRATE NITRITE TOTAL TOTAL (MG/L (MG/L AS N) AS N) 0.078 0.560 0.300 0.460 0.530 NITRO- NITRO- GEN, GEN, NO2+NO3 AMMONIA TOTAL TOTAL (MG/L (MG/L AS N) AS N) 0.010 6.040 <0.010 0.110 0.060 0.080 0.088 0.600 <0.050 0.410 0.520 0.610 0.300 0.170 0.280 0.060 0.400 0.190 NITRO- NITRO- GRN.AM- GBN, MONIA + ORGANIC ORGANIC TOTAL TOTAL (MG/L (MG/L AS N) AS N) 0.50 0.43 0.12 0.44 0.40 0.51 0.80 0.60 0.40 0.50 0.80 0.70 NITRO- GEN, TOTAL (MG/L AS N) 0.89 1.2 0.91 1.3 1.3 NITRO- GEN, TOTAL (MG/L AS N03) 3.9 5.3 4.6 5.8 5.8 DATE OCT 1991 15... DEC 04... FBB 1992 12... MAY 01... JUN 12... AUG 10... PHOS- PHORUS TOTAL (MG/L AS P) 0.280 0.200 0.070 0.200 0.250 0.250 BORON, COPPER, TOTAL TOTAL RECOV- ERABLE (UG/L AS B) 90 50 RECOV- ERABLE (UG/L AS CD) 80 20 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) 1200 120 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) 260 150 ZINC, TOTAL RECOV- CYANIDE TOTAL (MG/L AS CN) ERABLB (UG/L AS ZN) 100 <0.010 40 <;0.010 PHENOLS TOTAL (UG/L) MBTHY- LBNB BLUB ACTIVE SUB- STANCE (MG/L) 0.07 0.09 K = non-ideal count 336 RZO GRANDB DE LOZZA BASIN 50059100 RIO GRANDE DE LOIZA BELOW TRUJILLO ALTO, PR WATER-QUALITY RECORDS LOCATION.—Lat 18°21'35", long 66°00'15", 100 ft (30 m) downstream of Highway 181 bridge, 0, northwest of Trujillo Alto plaza, and 2.2 mi (3.5 km) northeast of Lago Lofza Reservoir. DRAINAGE AREA.--213 mi> (552 km»). PERIOD OP RECORD.—Water year* 1981 to current year. REMARKSi Plow controlled by Lago Loiza reservoir. HATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 4 mi (0.6 km) DATE OCT 1991 15... DEC 04... PBB 1992 21... MAY 11. .. JUN 16. .. AUG 12... TIME 1020 1050 1035 1100 1300 0740 DIS- CHARGE, INST. CUBIC FEET PER SECOND 11 10 11 3.0 10 14 SPE- CIFIC CON- DUCT- ANCE (US/CM) 418 366 350 418 425 310 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.6 7.1 7.9 7.3 7.0 7.5 TEMPER- ATURE WATER (DBG C) 30.5 25.5 27.5 31.0 32.5 27.5 TUR- BID- ITY (NTU) 1.0 8.6 2.2 8.3 6.9 3.7 OXYGEN, DIS- SOLVED (MG/L) 4.0 6.1 10.2 11.5 9.3 5.3 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 53 90 135 151 108 74 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 18 11 10 20 13 <10 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K9300 2900 K740 500 K90 2900 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 2000 690 K10 K140 K65 200 DATE OCT 1991 15... DEC 04... PBB 1992 21... MAY 11.. . JUN 16.. . ADG 12.. . HARD- NESS CALCIUM TOTAL DIS- (MG/L SOLVED AS (MG/L MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L CAC03) AS CA) AS MG) AS NA) 100 26 9.7 23 140 33 13 31 100 26 9.4 20 SODIUM AD- SORP- TION RATIO ALKA- POTAS- UNITY SIUM, WAT WH TOT PET SULPIDB FIELD TOTAL MG/L AS DIS- SOLVED (MG/L AS K) 1 4.3 2.8 0.9 2.9 CAC03 110 110 120 140 60 100 (MG/L CHLO- SULFATB RIDE, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS S) AS S04) AS CL) <0.5 19 <0.5 27 18 26 36 22 SOLIDS, RESIDUE DATE OCT 1991 15.. . DEC 04... PBB 1992 21... MAY 11.. . JUN 16... AUG 12... FLUO- SILICA, RIDE, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS AS F) SI02) 0.20 26 __ __ 0.20 25 __ 0.20 23 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 200 __ -- 252 __ 182 SOLIDS, DIS- SOLVED (TONS PER DAY) 5.98 __ — 2.01 __ 6.88 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) <1 22 3 <1 10 5 NITRO- GEN, NITRATE TOTAL (MG/L AS N) __ 0.890 0.540 0.450 0.640 0.960 NITRO- GEN, NITRITE TOTAL (MG/L AS <0 0 0 0 0 0 N) .010 .020 .020 .030 .010 .030 NITRO- GEN, N02+NO3 TOTAL (MG/L AS 0 0 0 0 0 0 N) .350 .910 .560 .480 .650 .990 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.030 0.030 0.050 0.070 0.040 0.060 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.77 0.27 0.35 0.43 0.16 0.24 K = non-ideal count RIO GRANDB DB LOIZA BASIN 50059100 RIO GRANDB DB LOIZA BELOW TRUJILLO ALTO, PR--Continued WATER-QUALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 337 DATE OCT 1991 15... DEC 04.. . PEB 1992 21... MAY 11... OUN 16.. . AUG 12. .. NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.80 0.30 0.40 0.50 0.20 0.30 NITRO- GEN, TOTAL (MG/L AS N) 1.2 1.2 0.96 0.98 0.85 1.3 NITRO- GEN, TOTAL (MG/L AS N03) 5.1 5.4 4.2 4.3 3.8 5.7 PHOS- PHORUS ARSENIC TOTAL TOTAL (MG/L (UG/L AS P) AS AS) 0.240 <1 0.210 0.210 0.200 1 0.120 0.190 BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 — — 100 __ __ BORON, TOTAL RECOV- ERABLE (UG/L AS B) 60 __ __ 50 __ -- CHRO- CADMIUM MIUM, COPPER, TOTAL TOTAL TOTAL RBCOV- RBCOV- RECOV- ERABLE BRABLB BRABLB (UG/L (UG/L (UG/L AS CD) AS CR) AS CU) <1 1 <10 __ -_ <1 <1 10 __ __ DATE OCT 1991 15... DEC 04.. . PBB 1992 21.. . MAY 11.. . JUN 16.. . AUG 12.. . IRON, TOTAL RECOV- ERABLE (UG/L AS PE) LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) SELE- NIUM, TOTAL (UG/L AS SB) SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CYANIDE TOTAL (MG/L AS CN) PHENOLS TOTAL (UG/L) MBTHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 110 1400 30 160 <0.10 <0.10 <0.010 10 <0.010 0.05 0.07 338 RIO GRANDB DB LOIZA BASIN 50061000 RIO GRANDB DB LOIZA AT CAROLINA, PR LOCATION.—Lat 18°22'39", long 65«57'08", Hydrologic Unit 21010005, on upstream right bank of Highway 3 bridge, at Km 11.5, 0.5 mi (0.8 km) southeast of Carolina Plaza, 3.3 mi (5.3 km) west of Can6vanas Plaza and 2.5 mi (4.0 km) southwest of Cerro San Jose. DRAINAGE ARBA.--243 mi* (629 km*). WATER-STAGS RECORDS PERIOD OF RECORD.—January 1991 to current year (gage-height only). GAGE.—Mater-stage recorder. Elevation of gage is 32.8 ft (10.0 m), from topographic map. REMARKS.—Flow regulated by Lago Loiza Dam. Gage-height and precipitation satellite telemetry at station. EXTREMES FOR CURRENT PERIOD.--JANUARY TO SEPTEMBER 1991i Maximum gage-height, 12.76 ft (3.889 m), July 16; minimum, 4.01 ft (1.222 m), Aug. 6. WATER YEAR 19921 Maximum gage-height, 33.18 ft (10.113 m), Jan. 6; minimum 3.91 ft (1.192 m), June 30. GAGE HEIGHT, FEET, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN MAX MIN OCT NOV DEC JAN FBB MAR APR JUN JUL AUG SEP 5.25 5.22 5.16 5.21 5.24 5.21 5.32 5.23 5.28 5.27 ___ ___ ___ 5. 5. 5. 5. 6. 7. 6. 4. 4. 4. 5. 5. 6. 5. 5. 4. 5. 5. 6. 7. 5. 5. . . • . 5. - - - 5. 7. 4. 13 00 25 40 70 33 88 84 83 85 76 41 14 95 03 83 02 83 50 19 03 45 79 71 77 83 86 17 -- -- -- 48 33 71 5. 4. 4. 4. 5. 5. 5. 4. 4. 4. 5. 6. 5. 5. 5. 5. 5. 5. 5. 6. 6. 6. 6. 5. 5. 5. 5. 5. 5. 5. 5. 5. 6. 4. 04 79 86 96 02 82 95 88 87 92 10 02 72 89 78 57 44 55 84 09 18 41 12 56 38 45 56 45 39 46 61 51 41 79 5 6 6 6 6 6 5 5 5 5 5 5 5 5 5 6 6 5 5 5 5 5 5 5 5 5 6 4 .81 .02 .24 .49 .63 .21 .30 .37 .23 .06 .12 .27 .54 .66 .93 .74 .63 .77 .82 .83 .86 .95 .00 .17 .36 .52 .55 .32 .45 .60 --- .55 .74 .77 5 5 6 6 6 6 5 5 5 6 6 6 6 6 4 4 4 4 5 6 5 5 5 4 5 5 5 5 5 5 5 5 6 4 .73 .87 .06 .29 .52 .01 .43 .54 .89 .09 .15 .35 .67 .54 .82 .86 .91 .92 .02 .12 .18 .07 .08 .99 .02 .12 .11 .09 .08 .20 .19 .55 .67 .82 5.14 5.19 5.28 5.28 5.27 5.33 5.38 5.34 5.29 5.24 5.18 5.14 5.18 5.24 5.25 5.27 5.24 5.22 5.26 5.18 5.21 5.17 5.11 5.10 5.09 5.21 5.28 5.24 5.26 5.26 --- 5.23 5.38 5.09 6.58 6.13 5.84 5.10 5.08 5.04 4.96 5.44 5.09 4.92 4.97 5.02 5.02 5.10 5.38 8.17 6.20 5.58 6.29 5.22 4.82 4.80 4.85 ! 4.85 ! 4.82 ! 4.86 ! 4.94 ! 5.43 5.14 ! 4.99 ! 4.97 ! 5.34 ! 8.17 4.80 t .90 5.09 .83 5.13 .81 5.06 .87 5.09 .86 5.28 .78 5.35 .83 5.83 .93 5.69 .98 5.34 5.01 5.28 5.04 5.23 5.03 5.32 .92 5.30 .95 5.25 .93 5.29 .89 5.30 .95 6.69 .85 6.38 .79 5.22 .85 5.31 .88 5.35 .90 6.77 >.04 6.55 >.02 5.49 >.06 6.31 >.09 5.65 >.29 5.46 7.32 5.47 >.55 7.51 >.15 6.88 >.10 >.05 5.66 1.32 7.51 1.78 5.06 OCT RIO GRANDB DB LOIZA BASIN 50061000 RIO GRANDB DB LOIZA AT CAROLINA, PR —Continued GAGB HEIGHT, FEET, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES NOV DEC JAN FBB MAR APR MAY JUN JUL A0O 339 SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN MAX MIN 5.46 6.59 6.71 5.46 5.42 5.36 5.30 5.33 5.12 5.08 5.14 5.15 6.12 5.18 5.22 5.23 5.19 5.23 5.37 5.47 5.61 5.57 5.51 5.41 5.41 5.41 5.43 5.56 5.71 6.26 7.20 5.56 7.20 5.08 6.58 6.22 5.93 5.76 5.66 5.68 7.80 11.26 10.23 6.79 5.39 6.27 5.40 6.18 5.37 5.38 6.19 5.49 5.44 5.61 6.03 6.99 6.54 6.05 6.61 5.42 6.06 5.95 5.95 5.55 6.33 11.26 5.37 5.34 5.03 6.45 5.08 5.44 5.13 ! 5.26 5.21 5.23 9.89 5.89 18.54 4 5.17 7.02 ! 5.04 6.17 5.04 6.14 5.04 6.75 5.05 5.08 5.05 5.51 5.16 5.12 5.20 5.96 5.85 4.96 5.10 5.30 5.07 5.26 5.07 5.83 5.06 .98 5.27 .86 6.35 .84 5.74 .82 5.29 .81 5.20 .72 5.24 .31 5.12 .87 5.14 .92 5.05 .88 5.13 .82 5.09 .86 5.06 .84 5.30 5.86 < 6.45 18.54 5.04 4.72 4 1.84 1.91 5.06 5.32 5.18 1.90 5.54 .89 .86 .79 .74 .83 .87 .85 .89 .92 .86 .90 .88 .79 .78 .75 .71 .68 .72 .65 .68 .72 .74 ! ___ i ___ i 1.87 4 5.54 ! 1.65 < .76 .82 .87 .83 .84 .87 .84 .82 .94 .93 .82 .78 .79 .82 .84 .93 .95 .10 .89 .81 .79 .98 .23 .94 .81 .82 .93 .89 i.OO >.19 >.30 1.91 i.30 1.76 5.41 5.50 5.56 5.61 5.65 5.72 5.78 5.90 6.01 6.15 6.26 6.35 6.39 6.40 6.40 6.12 5.13 5.03 5.00 4.94 .93 .93 .82 .78 .95 .01 .86 .85 5.07 5.65 5.51 6.40 4.78 5.59 6.27 4.97 4.81 4.82 5.04 4.94 4.88 4.91 4.98 4.99 4.98 5.01 4.96 4.89 4.85 4.89 6.25 6.53 5.65 4.94 4.88 6.70 11.29 6.52 12.94 7.33 6.08 5.56 6.11 5.80 5.88 12.94 4.81 5.80 6.97 5.95 6.22 5.00 5.85 6.46 5.27 7.05 6.00 6.19 6.67 7.10 6.17 4.99 6.08 5.18 5.48 4.77 5.10 7.64 4.83 4.74 5.84 4.83 4.77 4.68 4.69 4.71 4.74 —— 5.66 7.64 4.68 4.73 4.84 4.89 4.90 5.47 4.85 4.76 4.76 5.53 4.82 4.81 4.79 4.81 4.82 4.83 4.85 5.35 5.18 4.85 4.84 5.59 5.89 5.28 .93 .82 .86 .88 .15 .95 .91 5.02 5.03 6.15 4.73 5.03 4.97 4.99 5.06 7.98 7.15 5.98 4.91 5.60 5.37 6.26 4.92 4.94 5.18 6.29 4.99 4.90 4.97 5.13 4.98 5.00 5.02 5.03 4.99 5.15 5.17 5.17 5.55 5.56 5.61 5.60 5.40 7.98 4.90 5.66 5.47 5.28 5.19 5.42 6.36 6.16 6.87 6.12 5.63 6.26 5.92 6.20 6.15 5.81 5.56 6.65 5.23 6.12 9.50 10.19 7.12 6.47 5.67 6.28 5.71 5.95 6.48 6.04 6.27 6.26 10.19 5.19 WTR YR 1992 MEAN 5.55 MAX 18.54 MIN 4.65 340 RIO GRANDB DE LOIZA BASIN 50061800 RIO CANOVANAS NEAR CAMPO RICO, PR LOCATION.--Lat 18°19'08", long 65°53'21", Hydrologic Unit 21010005, at center pier on downstream side of bridge, on paved secondary road, 0.4 mi (0.6 km) northeast of junction of Highways 185 and 186, 1.5 mi (2.4 km) south of Campo Rico, and 4.4 mi (7.1 km) south of Loixa. DRAINAGE AREA.--9.84 mi' (25.48 km2 ). HATER-DISCHARGE RECORDS PERIOD OF RECORD.--March 1967 to current year. GAGE.—Hater-stage recorder and crest-stage gage. Elevation of gage is 225 ft (68 m), from topographic map. REMARKS.--Records fair except those for estimated daily discharges, which are poor. DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 e21 20 2 e!9 31 3 elO 14 4 ell 12 5 e!6 12 6 elO 33 7 e6.0 109 8 e5.4 377 9 e5.8 68 10 e5.4 79 11 5.0 21 12 5.3 16 13 5.5 13 14 5.0 11 15 4.7 9.9 16 .3 9.7 17 .2 8.9 18 .1 8.2 19 .1 7.7 20 .1 7.5 21 3.9 22 22 3.8 100 23 4.1 29 24 3.7 53 25 3.4 21 26 3.4 15 27 3.7 16 28 4.7 17 29 6.1 15 30 9.3 16 31 7.7 —— TOTAL 209.7 1171.9 MEAN 6.76 39.1 MAX 21 377 KEN 3.4 7.5 AC-PT 416 2320 CFSM .69 3.97 IN. .79 4.43 e Estimated STATISTICS OF MONTHLY MEAN MEAN 45.5 46.5 MAX 273 125 (WY) 1971 1985 KEN 6.74 6.66 (WY) 1968 1981 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC- FT) ANNUAL RUNOFF (CPSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 15 23 23 40 18 14 12 12 12 13 12 13 13 15 12 10 11 9.8 9.3 46 44 18 14 12 11 11 11 10 10 9.6 9.3 493.0 15.9 46 9.3 978 1.62 1.86 DATA 34.4 116 1971 5.82 1968 FOR 9.4 9.0 8.7 8.6 376 218 37 21 19 38 20 15 38 21 16 14 13 12 12 11 11 9.9 10 9.6 9.8 9.8 9.7 9.0 8.8 8.4 8.5 1021.2 32.9 376 8.4 2030 3.35 3.86 FOR HATER 24.2 62.4 1969 6.66 1977 8.0 7.5 7.8 8.5 8.4 12 15 9.5 8.1 8.4 8.0 7.4 7.3 7.2 7.2 6.8 6.5 6.3 6.5 6.7 6.2 6.6 6.8 21 7.0 6.7 6.8 6.8 6.2 ___ --- 237.2 8.18 21 6.2 470 .83 .90 YEARS 1967 19.6 48.4 1988 4.04 1977 5.8 5.7 5.6 5.5 6.0 5.9 6.1 10 6.9 6.0 5.6 5.6 5.5 5.6 6.5 5.9 9.3 11 9.1 7.2 6.4 15 12 7.1 5.9 5.5 5.6 5.4 5.4 5.1 5.0 213.2 6.88 15 5.0 423 .70 .81 - 1992 14.7 36.2 1969 3.54 1977 1991 CALENDAR YEAR 5109. 14. 377 2. 2. 10130 1. 19. 23 9. 3. 5 0 Nov 8 7 Jul 21 8 Jul 19 42 32 0 7 4.8 5.1 4.9 4.8 4.6 4.6 6.8 6.9 6.4 14 6.8 5.5 5.5 5.9 5.5 4.6 4.6 4.6 7.3 9.2 5.8 .9 .6 .4 .0 .5 .4 5.5 5.6 14 --- 180.1 6.00 14 4.0 357 .61 .68 289 339 41 16 10 169 44 16 13 12 11 11 8.7 7.9 8.1 14 17 11 19 13 10 9.2 339 201 34 128 49 25 17 14 12 1907.9 61.5 339 7.9 3780 6.25 7.21 11 14 9.2 23 16 17 57 24 14 20 19 147 32 34 19 72 43 19 13 12 22 18 12 10 9.6 9.2 9.7 9.5 9.5 9.7 734.4 24.5 147 9.2 1460 2.49 2.78 9.7 10 10 10 11 11 11 23 18 14 15 13 17 19 14 16 27 18 13 12 11 14 13 15 16 12 14 13 11 10 9.9 430.6 13.9 27 9.7 854 1.41 1.63 9.7 9.7 9.9 11 127 59 18 17 12 12 20 22 13 18 17 13 20 11 9.5 9.0 8.6 8.2 7.8 e7.4 e7.2 e7.0 e7.0 e6.8 e7.0 e!3 e22 539.8 17.4 127 6.8 1070 1.77 2.04 elO e7.4 e8.8 e8.0 e23 e26 e!4 «7.6 elO e!2 e8.0 «6.8 e6.2 e6.4 el5 e32 e29 e28 e50 e58 e20 e!7 13 11 9.5 8.7 7.9 7.4 8.5 16 --- 485.2 16.2 58 6.2 962 1.64 1.83 , BY HATER YEAR (WY) 16.3 53.2 1971 4.66 1984 FOR 1992 7624. 20. 377 3. 3. 5140 10. 3. 15120 2. 28. 31 10 5. 30.6 93.2 1969 4.28 1974 HATER YEAR 2 8 Nov 8 4 Oct 25 7 Oct 21 Jan 5 58 Jan 5 1 Oct 25 12 82 4 19.2 63.7 1970 2.80 1974 18.0 63.7 1979 3.72 1974 HATER 27 58 11 3160 1 15000 13 20110 2 38 45 13 5 26.7 137 1979 5.69 1991 YEARS 1967 .8 .0 .0 Oct .80 Jul .5 Jul Sep . 10 Sep .82 .32 .3 33.0 103 1979 5.20 1967 - 1992 1971 1977 9 1970 24 1977 18 1977 13 1982 13 1982 RIO GRANDE DB LOIZA BASIN 50061800 RIO CANOVANAS NEAR CAMPO RICO, PR—Continued WATER QUALITY RECORDS PERIOD OF RECORD.--WATER YEARS AUGUST 1981 TO CURRENT YEAR 341 DATE MAR. MAY APR. 11 22 09 TIME 1335 1150 1315 STREAM? LOW, INSTANTANEOUS (CPS) 5.43 9.43 6.33 SPECIFIC CON- DUCTANCE (DHHOS) 190 200 190 TEMPERA- TURE (DBG C) 25.0 26.5 24.5 DATE JUN. JUL. 24 23 TIME 0832 0953 STRBAMFLOW, INSTANTANEOUS (CPS) 10.8 13.3 SPECIFIC CON- DUCTANCE (UMHOS) 210 220 TEMPERA- TURE (DBG C) 25.5 27.0 342 THIS PAGE WAS LEFT BLANK INTENTIONALLY ATLANTIC OCEAN -./ r J /•" — f . / FAJAB: 0655 ~" """ -^'<r-- f > !^ V^'tf. ; J \ * "- - *v i * u ./• \ v, ir"^ S«- /' ', ' . : ,-' S / . ' i I r \ ^•. k- ' ^•. / - \ > l- • S ^ * \ ' -- i EXPLANATION 0670 SURFACE-WATER STATION AND NUMBER QUALITY-OF-WATER STATION AND NUMBER 343 Figure 21.-Northeastern river basins the Rio Herrera to Rio Anton Ruiz basins. 344 RIO ESPIRITU SANTO BASIN 50063440 QUEBRADA SONADORA NEAR EL VERDE, PR LOCATION.—Lat 18°19'24", long 65<>49'03", Hydrologic Unit 21010005, in Caribbean National Forest, at El Yungue, 0.6 mi (1.0 km) upstream from Rio Espiritu Santo, 0.2 mi (0.3 km) upstream from Highway 186, and about 1.2 mi (1.9 km) south of El Verde. DRAINAGE AREA.--1.01 mi 1 (2.62 km»). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—March 1983 to current year. GAGE.—Water-stage recorder and crest-stage gage. Elevation of gage is 1,230 ft (375 m), from topographic map. REMARKS.--Records poor. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV 1 7.1 9.0 2 5.1 4.2 3 2.5 5.7 4 3.1 3.2 5 6.5 9.4 6 2.5 17 7 1.5 46 8 1.3 89 9 1.2 18 10 2.4 12 11 1.6 3.0 12 7.5 3.7 13 2.4 3.1 14 1.3 2.0 15 1.1 1.7 16 .89 4.0 17 .81 1.9 18 .76 1.3 19 .65 1.1 20 .57 1.1 21 .49 46 22 .42 39 23 .40 30 24 .33 20 25 e.29 6.1 26 .27 12 27 .24 9.7 28 .21 9.2 29 .21 12 30 .23 7.8 31 .20 —— TOTAL 54.07 428.2 MEAN 1.74 14.3 MAX 7.5 89 MIN .20 1.1 AC-FT 107 849 CFSM 1.73 14.1 IN. 1.99 15.77 e Estimated DEC 5.7 17 38 10 12 6.2 3.5 7.3 5.4 3.9 2.2 9.9 5.9 4.1 1.7 2.8 1.4 2.1 2.2 14 3.5 1.8 1.6 1.1 .97 .92 1.2 1.5 1.4 1.6 1.3 172.19 5.55 38 .92 342 5.50 6.34 JAN 1.5 .90 .67 .56 51 28 6.2 3.6 32 39 6.0 7.7 35 5.8 4.2 3.4 2.9 2.5 2.2 2.0 1.7 1.6 1.4 2.1 2.1 2.6 1.4 4.2 1.8 .93 .70 255.66 8.25 51 .56 507 8.17 9.42 STATISTICS OF MONTHLY MEAN DATA FOR WATER MEAN 6.90 10.9 MAX 17.1 20.1 (WY) 1986 1985 MIN 1.74 2.47 (WY) 1992 1991 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 8.06 21.6 1988 .95 1990 FOR 6.28 10.8 1988 3.41 1985 FEB .54 .42 .49 1.1 .59 17 4.1 1.8 .83 6.6 1.2 .66 .49 .39 .33 .26 .20 .19 .21 .44 .20 2.4 .68 1.1 .63 2.0 .57 e.53 e.28 —— 46.23 1.59 17 .19 92 1.58 1.70 YEARS 1983 6.66 12.0 1988 1.59 1992 MAR e.21 e.22 e.21 e.18 .29 .33 29 2.6 .77 .60 .49 8.8 1.8 1.7 2.0 .69 16 27 7.6 2.6 1.3 5.6 7.7 1.4 .99 .93 .76 .67 .64 5.6 1.9 130.58 4.21 29 .18 259 4.17 4.81 - 1992 6.08 14.7 1990 2.32 1984 1991 CALENDAR YEAR 1717. 4. 89 . . 3410 4. 63. 13 1. . 35 71 Nov 8 10 Aug 8 11 Aug 6 66 25 6 27 APR .88 .73 .44 .32 .32 1.2 15 13 6.6 2.0 1.3 12 5.3 3.0 1.9 .89 .77 28 4.8 1.7 1.0 .82 .73 .63 .55 .48 .43 .38 6.2 32 —— 143.37 4.78 32 .32 284 4.73 5.28 MAY 147 76 5.5 2.0 1.4 63 8.9 2.8 6.8 8.8 11 1.9 1.3 1.1 .95 35 1.8 1.1 1.1 1.5 .76 .62 57 18 5.6 14 11 1.6 1.4 2.1 1.2 492.23 15.9 147 .62 976 15.7 18.13 JUN 1.3 3.6 .72 3.1 1.7 11 8.4 2.3 .96 29 18 14 4.5 3.7 1.8 42 3.9 1.5 1.9 .85 6.5 1.5 3.5 .77 .70 .47 1.4 .45 .30 .23 --- 170.05 5.67 42 .23 337 5.61 6.26 JUL .18 .15 .14 .12 .27 .12 .09 7.6 8.9 2.0 20 1.2 3.9 14 14 8.8 24 9.5 1.8 7.9 6.5 18 7.4 8.4 13 1.7 13 6.3 8.1 1.2 .55 208.82 6.74 24 .09 414 6.67 7.69 AUG .38 .49 3.1 2.5 23 53 4.8 3.5 1.6 1.9 23 11 4.3 4.4 19 2.7 3.6 2.0 .90 2.3 el. 5 e.33 .36 2.0 .25 .50 .45 .46 1.2 .13 9.3 183.95 5.93 53 .13 365 5.88 6.78 SEP .38 .79 1.8 .89 12 10 1.8 5.1 12 .77 .93 .23 .18 .20 e3.0 e4.0 26 6.8 el.O elO e4.0 e.60 e.50 e.45 e.30 e.25 e.23 e.21 e.20 e.20 104.81 3.49 26 .18 208 3.46 3.86 , BY WATER YEAR (WY) 5.25 9.99 1987 1.09 1984 FOR 1992 2390 6 147 1180 8 4740 6 88 17 1 8.60 15.9 1992 4.02 1991 WATER YEAR .16 .53 May 1 . 09 Jul 7 . 15 Jul 1 May 1 . 14 May 1 .47 .03 .8 .30 6.01 13.7 1987 .98 1985 6.66 12.8 1983 2.36 1991 WATER 7 9 4 216 2230 9 5110 6 94 17 3 7.79 14.5 1988 3.37 1991 YEARS 1983 .05 .48 .46 .09 .11 .42 .99 .91 .0 .69 Dec Jul Aug Dec Dec 6.43 15.6 1989 2.34 1986 - 1992 1988 1991 7 1987 7 1992 6 1991 7 1987 7 1987 345 RIO ESPIRITU SANTO BASIN 50063440 QUBBRADA SONADORA NEAR EL VERDE, PR--Continued HATER QUALITY RECORDS PERIOD OF RECORD.--HATER YEARS APRIL 1983 TO CURRENT YEAR STRBAMFLOW, SPECIFIC CON- TEMPERA- STRBAMFLOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCB TURB DATS TIME INSTANTANEOUS DUCTANCB TURB (CFS) (UMHOS) (DBQ C) (CFS) (UMHOS) (DBO C) FEB. 20 1056 0.43 50 20.5 AUQ. 25 1006 0.23 40 21.0 MAR. 12 1325 0.45 50 21.5 SEP. 16 1022 5.89 50 23.5 JUN. 23 1148 7.10 60 24.5 346 RIO ESPIRITO SANTO BASIN 50063500 QUBBRADA TORONJA AT EL VERDE, PR LOCATION.—Lat 18°19'43", long 65°49'14", Hydrologic Unit 21010005, in Caribbean National Forest, at downstream side of culvert on Highway 186, 0.2 mi (0.3 km) upstream from Rio Bspiritu Santo, and about 0.9 mi (1.4 km) south of El Verde. DRAINAGE AREA.--0.064 mi' (0.166 km'). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—April 1983 to current year. GAGE.—Water-stage recorder and concrete broad-V-notch crested weir. Elevation of gage is 876 ft (267 m), from topographic map. REMARKS.--Records fair. DAY OCT DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES NOV DEC JAN FBB APR MAY JUN JUL SEP 1 .21 .11 2 .15 .11 3 .08 .07 4 .10 .16 5 .11 .39 6 .08 .60 7 .06 1.3 8 .05 3.3 9 .05 .59 10 .06 .36 11 .05 .19 12 .09 .18 13 .06 .15 14 .05 .12 15 .05 .12 16 .04 .14 17 .04 .11 18 .04 .10 19 .04 .09 20 .04 .09 21 .04 1.7 22 .04 1.8 23 .04 .78 24 .04 .84 25 .03 .33 26 .03 .34 27 .03 .31 28 .03 .27 29 .03 .28 30 .03 .31 31 .03 TOTAL 1.82 15.24 MEAN .059 .51 MAX .21 3.3 MIN .03 .07 AC-FT 3.6 30 CFSM .98 8.47 IN. 1.13 9.45 STATISTICS OF MONTHLY MEAN MEAN .34 .59 MAX 1.35 1.34 (WY) 1986 1985 MIN .059 .15 (WY) 1992 1991 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS .25 .28 .76 .38 .34 .24 .18 .25 .25 .18 .15 .24 .15 .14 .13 .16 .13 .18 .13 .25 .17 .13 .12 .11 .10 .12 .15 .14 .13 .11 .09 6.14 .20 .76 .09 12 3.30 3.81 DATA .41 1.34 1988 .091 1990 FOR .12 .12 .11 .10 1.2 .84 .25 .20 .82 1.5 .35 .32 1.2 .34 .22 .19 .17 .15 .14 .13 .15 .14 .13 .13 .12 .12 .11 .13 .12 .12 .12 9.86 .32 1.5 .10 20 5.30 6.11 .11 .10 .12 .12 .08 .17 .12 .10 .10 .17 .10 .09 .09 .09 .08 .10 .10 .09 .10 .09 .11 .10 .08 .08 .07 .08 .05 .05 .04 —— 2.78 .096 .17 .04 5.5 1.60 1.72 FOR WATER YEARS 1983 .27 .58 1988 .14 1986 .24 .44 1988 .092 1987 .04 .04 .04 .04 .04 .04 .12 .05 .04 .04 .04 .05 .04 .04 .03 .03 .19 .13 .09 .06 .04 .07 .06 .04 .04 .04 .04 .04 .03 .03 .04 1.66 .054 .19 .03 3.3 .89 1.03 - 1992 .23 .63 1990 .054 1992 1991 CALENDAR YEAR 55. , 3. . 110 2. 34. . . . 48 15 3 Nov 8 01 Aug 5 01 Aug 5 53 40 33 08 03 .04 .04 .04 .04 .04 .04 .14 .13 .06 .06 .06 .20 .12 .06 .05 .05 .05 .21 .11 .06 .05 .04 .04 .04 .04 .04 .04 .03 .26 1.3 —— 3.48 .12 1.3 .03 6.9 1.93 2.16 1.7 2.2 .35 .22 .18 1.3 .47 .26 .27 .44 .28 .20 .17 .16 .15 .75 .21 .16 .15 .14 .12 .12 1.4 .89 .29 .53 .48 .35 .36 .42 .29 15.01 .48 2.2 .12 30 8.07 9.31 .27 .25 .22 .23 .21 .34 .32 .24 .20 .58 .40 .35 .28 .28 .20 1.5 .47 .28 .24 .20 .22 .19 .21 .16 .16 .14 .15 .13 .12 .11 8.65 .29 1.5 .11 17 4.81 5.36 .10 .10 .09 .09 .10 .08 .07 .16 .25 .14 .30 .12 .14 .47 .31 .21 .53 .24 .16 .21 .16 .52 .26 .33 .41 .21 .37 .26 .21 .18 .15 6.93 .22 .53 .07 14 3.73 4.30 .15 .17 .16 .26 1.9 .95 .33 .25 .23 .23 .86 .30 .28 1.5 .55 .54 .37 .34 .31 .32 .28 .26 .34 .31 .29 .29 .27 .23 .21 .21 .27 12.96 .42 1.9 .15 26 6.97 8.04 .19 .18 .16 .14 .22 .27 .13 .09 .84 .10 .09 .08 .07 .06 .08 .18 2.9 .35 .16 .43 .93 .33 .59 .31 .20 .18 .19 .18 .18 .19 10.00 .33 2.9 .06 20 5.56 6.20 , BY WATER YEAR (WY) .20 .61 1987 .035 1984 FOR 1992 94. . 3. . . 19 1. . 188 4. 58. . . .33 .64 1986 .11 1991 WATER YEAR 53 26 3 Nov 8 03 Oct 25 03 Oct 25 Sep 17 73 Sep 17 03 Oct 24 30 61 49 15 04 .24 .61 1987 .056 1991 .23 .67 1983 .046 1991 WATER 6 101 2 219 5 68 .30 .54 1988 .063 1991 YEARS 1983 .30 .45 .17 .9 Nov .01 Apr .01 Aug Aug .61 Aug .00 Apr .05 .59 .66 .15 .05 .29 .61 1989 .060 1991 - 1992 1988 1984 27 1987 10 1983 5 1991 13 1990 13 1990 10 1983 RIO ESPIRITO SANTO BASIN ^ 50063500 QOEBRADA TORONJA AT BL VBRDB, PR—Continued WATER QUALITY RECORDS PERIOD OF RECORD.--WATER YEARS APRIL 1983 TO CURRENT YEAR STREAMFLOW, SPECIFIC CON- TEMPERA- STRBAMFLOW, SPECIFIC CON- TBMPBRA- DATB TIME INSTANTANEOUS DUCTANCB TORE DATE TIME INSTANTANEOUS DUCTANCB TURB (CFS) (UMHOS) (DBG C) (CFS) (UMHOS) (DBG C) MAR. 12 1227 0.03 90 22.0 JUN. 23 1248 0.22 80 24.0 MAY 27 1457 1.35 80 24.0 348 RIO ESPIRITD SANTO BASIN 50063800 RIO ESPIRITD SANTO NEAR RIO GRANDB, PR LOCATION.--Lat 18021'37", long 65°48'49", Hydrologic Unit 21010005, at left abutment, on downstream side of bridge on Highway 966, 0.1 mi (0.2 km) upstream from Quebrada Jimenez, and 1.9 mi (3.1 km) southeast of Rio Grande. DRAINAGE AREA.--8.62 mi 1 (22.33 km'). HATER-DISCHARGE RECORDS PERIOD OP RECORD.—February 1959 to April 1963 (annual low-flow and occasional measurements only), August 1966 to current year. GAGE.—Water-stage recorder and crest-stage gage. Elevation of gage is 40 ft (12 m), from topographic map. REMARKS.--Records fair except those for estimated daily discharges, which are poor. DISCHARGE, CUBIC PBBT PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN PBB MAR APR MAY JUN JUL AUG SEP 1 57 e9.9 2 40 e!4 3 21 16 4 21 14 5 38 e26 6 20 e56 7 13 el 13 8 12 e700 9 11 101 10 14 88 11 14 15 12 37 15 13 21 15 14 12 10 15 11 9.3 16 10 17 17 9.6 11 18 9.2 8.7 19 9.3 8.0 20 9.6 8.5 21 8.6 e207 22 8.5 e446 23 8.5 119 24 8.1 157 25 7.7 27 26 7.8 38 27 7.5 64 28 7.4 46 29 7.3 32 30 7.3 40 31 6.1 TOTAL 474.5 2431.4 MEAN 15.3 81.0 MAX 57 700 MIN 6.1 8.0 AC-FT 941 4820 CFSM 1.78 9.40 IN. 2.05 10.49 e Estimated STATISTICS OP MONTHLY MEAN MEAN 65.0 85.6 MAX 202 196 (WY) 1971 1985 MIN 12.3 29.1 (WY) 1969 1982 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK PLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 24 54 162 64 48 34 23 40 36 33 22 50 41 40 23 28 23 26 24 89 51 25 23 19 17 17 20 20 21 20 17 1134 36.6 162 17 2250 4.24 4.89 DATA 75.0 179 1971 18.1 1990 FOR 20 17 16 14 481 212 45 24 147 356 43 37 189 40 27 24 22 20 18 18 17 17 16 17 19 21 16 23 20 14 13 1963 63.3 481 13 3890 7.35 8.47 FOR WATER 52.0 119 1969 18.5 1977 13 13 13 19 15 81 37 22 15 38 18 14 13 12 12 12 11 11 11 13 12 23 15 16 15 22 15 15 11 —— 537 18.5 81 11 1070 2.15 2.32 YEARS 1966 50.9 117 1982 10.8 1983 10 10 10 9.7 10 11 180 31 11 9.3 8.6 21 20 9.8 18 9.3 49 83 47 21 13 28 30 13 10 9.9 9.1 8.8 9.0 18 22 749.5 24.2 180 8.6 1490 2.80 3.23 - 1992 41.6 153 1990 13.0 1977 1991 CALENDAR YEAR 13871. 38. 700 6. 7. 27510 4. 59. 88 20 8. 0 0 Nov 8 1 Oct 31 3 Oct 25 41 86 6 10 9.2 8.3 8.1 8.3 7.5 45 46 36 19 12 32 42 17 18 9.0 8.2 132 50 17 11 9.4 8.8 8.5 8.2 8.4 8.2 8.3 16 250 871.4 29.0 250 7.5 1730 3.37 3.76 1010 628 28 12 8.7 428 38 14 15 37 22 10 7.5 6.6 6.3 204 13 9.0 7.8 9.4 7.5 7.0 412 178 27 113 47 17 14 20 16 3372.8 109 1010 6.3 6690 12.6 14.56 13 40 13 21 16 68 57 26 13 104 41 90 27 21 15 295 37 17 15 11 17 12 16 9.0 8.3 7.3 13 8.1 7.5 7.2 1045.4 34.8 295 7.2 2070 4.04 4.51 6.7 6.4 6.0 6.2 6.7 5.5 5.0 31 22 11 52 8.9 10 57 34 27 136 34 13 24 17 70 29 53 63 20 67 41 43 24 22 951.4 30.7 136 5.0 1890 3.56 4.11 23 31 38 52 488 318 70 52 43 35 225 54 53 162 56 30 34 24 21 29 20 19 19 28 17 16 19 16 20 17 80 2109 68.0 488 16 4180 7.89 9.10 23 23 30 26 69 90 33 22 94 22 24 20 17 16 23 66 291 107 57 e200 e!40 eSO e48 e40 e25 e22 e!9 e!8 e!7 e!7 1649 55.0 291 16 3270 6.38 7.12 , BY WATER YEAR (WY) 45.9 119 1981 6.27 1984 FOR 1992 17288 47 1010 5 6 9520 10 4 34290 5 74 90 20 8 70.9 185 1979 14.9 1973 WATER YEAR .4 .2 May 1 . 0 Jul 7 . 1 Jul 1 May 1 . 89 May 1 . 8 Jul 7 .48 .61 .5 47.8 120 1970 10.0 1975 51.5 114 1983 11.1 1975 WATER 59 98 37 2600 4 4 19200 15 4 42990 6 93 125 26 11 62.5 123 1988 22.3 1974 YEARS 1966 - .3 .6 .3 Dec 7 . 1 Jul 3 .4 Jun 30 Aug 13 .74 Aug 13 . 0 Jul 3 .88 .53 57.2 191 1989 17.7 1971 1992 1979 1974 1987 1975 1975 1990 1990 1975 RIO BSPIRITO SANTO BASIN 50063800 RIO BSPIRITO SANTO NEAR RIO GRANDS, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--Water year* 1958, 1961-66, 1968 to current year. WATBR-QOALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 349 DATE OCT 1991 02. .. DEC 16. .. FBB 1992 12... MAY 13... JUN 29. .. AUG 17. .. TIME 0900 1120 0920 1045 1245 1120 DIS- CHARGE, INST. CUBIC FEET PER SECOND 49 25 13 7.8 7.6 33 SPE- CIFIC CON- DUCT- ANCE (US /CM) 92 105 106 90 120 92 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.5 7.2 6.7 6.3 6.9 7.0 TEMPER- ATURE WATER (DBG C) 24.0 22.5 22.0 25.0 29.0 26.5 TUR- BID- ITY (NTU) 25 2.5 1.6 1.7 1.5 2.5 OXYGEN, DIS- SOLVED (MG/L) 7.0 8.7 8.1 7.8 6.1 7.8 OXYGEN, OXYGEN DIS- DEMAND, SOLVED CHBM- (PBR- ICAL CENT (HIGH SATUR- LEVEL) ATION) (MG/L) 82 19 118 <10 106 <10 94 <10 81 <10 97 <10 COLI- FORM, FECAL, 0.45 UM-MP (COLS./ 100 ML) K6500 560 540 220 K900 600 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 4100 340 550 360 K90 K160 DATE OCT 1991 02.. . DEC 16.. . FBB 1992 12.. . MAY 13.. . JUN 29.. . AUG 17... HARD- NESS TOTAL (MG/L AS CAC03 ) (00900) 27 -- -- 26 -- 28 CALCIUM DIS- SOLVED (MG/L AS CA) (00915) 5.9 -- -- 5.7 ~- 5.9 MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) (00925) 3.0 -- -- 2.9 -- 3.1 SODIUM, DIS- SOLVED (MG/L AS NA) (00930) 7.6 -- -- 7.3 ~- 6.9 SODIUM AD- SORP- TION RATIO (00931) 0.6 __ -- 0.6 -- 0.6 POTAS- SIUM, DIS- SOLVED (MG/L AS K) (00935) 0.60 -- -- 0.50 -- 0.50 ALKA- LINITY WAT WH TOT FBT FIELD MG/L AS CACO3 (00410) 26 30 70 26 38 30 SULPIDB TOTAL (MG/L AS S) (00745) <0.5 -- -- <0.5 -- — SULFATB DIS- SOLVED (MG/L AS SO4) (00945) 2.7 -- -- 1.9 -- 1.7 CHLO- RIDE, DIS- SOLVED (MG/L AS CL) (00940) 11 -- — 10 — 9.1 SOLIDS, RESIDUE DATE OCT 1991 02.. . DEC 16. .. FBB 1992 12.. . MAY 13.. . JUN 29.. . AUG 17... FLDO- RIDB, DIS- SOLVED (MG/L AS F) <0.10 -- -- <0.10 -- <0.10 SILICA, DIS- SOLVED (MG/L AS SI02) 15 -- -- 16 — 14 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 61 -- -- 60 -- 60 SOLIDS, DIS- SOLVED (TONS PER DAY) 8.20 -- -- 1.26 -- 5.35 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 10 1 8 3 <1 3 NITRO- NITRO- NITRO- NITRO- NITRO- GEN, GEN, GEN, GEN, GEN, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC TOTAL TOTAL TOTAL TOTAL TOTAL (MG/L (MG/L (MG/L (MG/L (MG/L AS N) AS N) AS N) AS N) AS N) 0.090 0.020 <0.010 <0.010 0.110 0.087 <0.050 <0.010 <0.050 <0.010 <0.050 <0.010 <0.050 0.030 <0.010 0.010 0.030 0.030 0.020 0.27 K = non-ideal count 350 RIO BSPIRITU SANTO BASIN 50063800 RIO BSPIRITU SANTO NEAR RIO GRANDE, PR—Continued HATER-QUALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 02.. . DEC 16.. . FBB 1992 12.. . MAY 13.. . JUN 29.. . AUG 17... DATE OCT 1991 02. .. DEC 16.. . FBB 1992 12.. . MAY 13... JUN 29.. . AUG 17.. . NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.30 <0.20 <0.20 <0.20 <0.20 <0.20 IRON, TOTAL RECOV- ERABLE (DG/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) 0.41 — — — — -- LEAD, TOTAL RECOV- ERABLE (DG/L AS PB) NITRO- GEN, TOTAL (MG/L AS NO3) 1.8 -- -- -- -- -- MANGA- NESE, TOTAL RECOV- ERABLE (DG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.020 <0.010 •cO.010 •cO.010 <0.010 0.010 MERCURY TOTAL RECOV- ERABLE (DG/L AS HG) ARSENIC TOTAL (UG/L AS AS) <1 -- -- <1 -- -- SELE- NIUM, TOTAL (DG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 -- — <100 — — SILVER, TOTAL RECOV- ERABLE (DG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) -- -- -- 20 -- -- ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 — — <1 — — CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) 1 -- -- <1 -- -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CO) <10 — — <10 — -- MBTHY- LENB BLUE ACTIVE SUB- STANCE (MG/L) 1600 110 30 10 <0.10 <0.10 10 <o.oio <0.010 0.03 0.02 RIO BSPIRITO SANTO BASIN 50064200 RIO GRANDB NEAR BL VBROB, PR 35 1 LOCATION.--Lat 18«20'54", long 65«50'30". Hydrologic Unit 21010005, on left bank 250 ft (7.6 •) upstream side of bridge at Hwy 960, 0.05 mi (0.08 km) southwest of junction of Highways 956 and 960, 1.1 mi (1.8 km) west of Bl Verde, and 2.7 mi (4.3 km) south of Rio Qrande. DRAINAGE AREA.--7.31 mi> (18.93 Km'). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--May 1967 to December 1970, January 1972 to September 1982, August 1990 to current year. QAQB.--Water-stage recorder. Elevation of gage is 131 ft (40 m), from topographic map. REMARKS.—Records fair. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUO SEP 1 39 46 2 33 49 3 17 37 4 14 29 5 29 36 6 16 72 7 12 136 8 9.7 385 9 10 111 10 11 91 11 9.3 27 12 38 20 13 20 19 14 11 15 15 9.4 13 16 8.7 15 17 8.3 13 18 8.1 11 19 8.1 9.8 20 7.3 9.1 21 7.; 105 22 6.9 151 23 6.7 67 24 7.6 86 25 7.0 22 26 6.8 20 27 6.3 32 28 6.3 49 29 6.2 25 30 8.8 41 31 6.9 - — TOTAL 395.5 1741.9 MEAN 12.8 58.1 MAX 39 385 MIN 6.2 9.1 AC-FT 784 3460 CFSM 1.75 7.94 IN. 2.01 8.86 STATISTICS OF MONTHLY MEAN MEAN 67.4 74.2 MAX 392 172 (WY) 1971 1970 MIN 8.45 14.3 (WY) 1969 1981 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 30 49 74 55 29 21 18 24 27 31 23 34 32 35 18 19 18 16 15 80 58 28 25 20 19 18 21 20 20 17 16 910 29.4 80 15 1800 4.02 4.63 DATA 51.6 140 1971 13.8 1968 FOR 19 16 14 14 215 138 43 24 41 107 33 27 95 35 25 22 20 19 18 17 17 16 16 17 17 18 17 17 18 14 13 1122 36.2 215 13 2230 4.95 5.71 FOR WATER 43.5 151 1969 10.1 1977 13 14 13 13 13 49 30 16 12 19 13 9.8 8.6 8.0 7.6 7.1 6.7 6.5 7.2 6.8 6.4 8.8 7.7 6.3 7.4 8.2 7.7 11 7.8 ___ --- 344.6 11.9 49 6.3 684 1.63 1.75 YEARS 1967 32.0 76.4 1969 5.80 1977 6.7 6.4 6.1 5.7 5.9 6.0 41 25 8.3 6.4 5.9 5.5 5.7 5.9 15 7.4 15 29 28 11 7.6 25 14 8.4 6.8 6.0 5.5 5.2 5.0 4.8 6.0 340.2 11.0 41 4.8 675 1.50 1.73 - 1992 23.3 54.4 1969 4.50 1977 1991 CALENDAR YEAR 7907. 21. 385 2. 2. 15680 2. 40. 48 12 4. 4 7 Nov 8 2 Aug 15 5 Aug 10 96 24 1 5.3 4.8 4.6 4.4 4.4 4.2 16 15 17 12 5.3 13 16 6.1 9.5 4.4 3.9 9.8 20 7.5 5.6 4.5 4.3 4.1 4.1 3.9 3.7 3.8 11 47___ 275.2 9.17 47 3.7 546 1.25 1.40 405 262 38 19 14 165 46 21 18 37 25 17 13 12 13 56 22 20 15 19 13 12 279 106 53 108 52 28 23 23 21 1955 63.1 405 12 3880 8.63 9.95 17 22 19 46 25 42 78 35 19 49 33 79 46 41 22 89 51 26 16 13 21 16 13 11 10 9.4 10 9.3 8.8 8.5 885.0 29.5 89 8.5 1760 4.04 4.50 8.3 8.0 8.0 7.8 8.9 8.3 7.9 41 24 12 22 12 20 38 23 29 76 30 16 16 13 28 18 50 32 14 35 22 14 11 11 664.2 21.4 76 7.8 1320 2.93 3.38 11 11 14 16 192 132 43 31 19 17 71 29 32 71 34 34 32 18 16 15 14 13 13 14 12 12 12 11 11 11 38 999 32.2 192 11 1980 4.41 5.08 19 12 15 13 35 43 18 12 17 13 12 11 9.3 9.4 12 40 65 39 54 107 67 28 27 23 15 13 11 11 10 11 —— 771.7 25.7 107 9.3 1530 3.52 3.93 , BY WATER YEAR (WY) 31.4 119 1978 8.55 1975 FOR 1992 10404 28 405 3 4 4450 12 3 20640 3 52 53 16 6 60.1 203 1969 10.2 1974 WATER YEAR .3 .4 May 1 .7 Apr 27 . 1 Apr 22 Nov 8 . 88 Nov 8 .6 Apr 26 .89 .95 .4 34.2 86.5 1968 6.22 1975 38.0 109 1969 9.05 1991 WATER 44 87 25 3470 2 •2 17400 15 1 32020 6 82 85 18 7 46.5 90.0 1968 7.39 1991 YEARS 1967 .2 .1 .8 May .2 Aug .5 Aug Sep .50 Sep .6 Mar .05 .14 .2 50.9 153 1975 12.4 1967 - 1992 1969 1991 21 1969 15 1991 10 1991 16 1975 16 1975 13 1977 352 RIO BSPIRITU SANTO BASIN 50064200 RIO GRANDB NEAR EL VERDE, PR--Continued WATER QUALITY RECORDS PERIOD OP RECORD.-- OCTOBER 1990 TO CURRENT YEAR STREAM?LOW, DATE TIME INSTANTANEOUS (CPS) MAR. 12 1453 APR. 10 1140 5.37 9.57 SPECIFIC CON- DUCTANCE (UMHOS) 140 80 TEMPERA- TURE (DBG C) 26.5 26.0 STREAMFLOW, DATE TIME INSTANTANEOUS (CPS) MAY 22 0910 JUN. 23 1032 11.8 13.4 SPECIFIC CON- DUCTANCE (UMHOS) 120 110 TEMPERA- TURE (DBQ C) 25.0 25.0 RIO MAMEYBS BASIN 50065500 RIO MAHEYBS NEAR SABANA, PR 353 LOCATION.—Lat 18 0 19'46", long 65°45'04", Hydrologic Unit 21010005, on left bank, at bridge on Highway 988, 1.4 mi (2.3 km) west of Sabana, 2.0 mi (3.2 km) downstream from Rio de la Mina, and 3.2 mi (5.1 km) southeast of Mameyes. DRAINAGE AREA.--6.88 mi> (17.82 km'). HATER-DISCHARGE RECORDS PERIOD OF RECORD.--August 1967 to December 1973, June 1983 to current year. OAGB.—Water-stage recorder and crest-stage gage. Elevation of gage is 275 ft (84 m), from topographic map. REMARKS.--Record* fair except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 70 114 2 64 67 3 43 56 4 45 37 5 63 82 6 38 141 7 29 259 8 28 641 9 34 206 10 44 147 11 29 84 12 45 77 13 34 71 14 31 58 15 29 64 16 27 92 17 25 67 18 24 53 19 33 47 20 24 44 21 20 233 22 20 228 23 26 127 24 19 122 25 18 72 26 18 91 27 19 94 28 18 84 29 24 89 30 21 86 31 18 —— TOTAL 980 3633 MEAN 31.6 121 MAX 70 641 MIN 18 37 AC-FT 1940 7210 CFSM 4.59 17.6 IN. 5.30 19.64 e Estimated STATISTICS OF MONTHLY MEAN MEAN 71.4 84.8 MAX 240 191 (WY) 1971 1985 MIN 20.3 36.3 (WY) 1969 1974 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN- DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC- FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 62 94 163 92 86 65 51 61 52 51 39 59 53 75 32 44 32 33 31 60 42 31 28 24 23 23 23 26 24 23 31 1533 49.5 163 23 3040 7.19 8.29 DATA 61.9 164 1971 16.6 1990 FOR 26 21 19 17 487 190 74 59 134 222 78 68 117 58 50 47 45 41 38 35 33 31 31 32 38 39 30 44 35 28 26 2193 70.7 487 17 4350 10.3 11.86 FOR WATER 54.6 105 1969 25.0 1985 24 25 27 68 34 114 49 33 28 50 30 26 24 24 23 22 22 21 25 25 21 40 24 24 23 31 34 29 21 ___ --- 941 32.4 114 21 1870 4.72 5.09 YEARS 1967 40.6 68.0 1988 21.7 1968 18 18 17 18 19 20 152 47 22 19 18 60 31 38 38 20 55 88 e30 e29 e22 e35 e66 e35 e20 e23 e24 e70 e35 ellO e80 1277 41.2 152 17 2530 5.99 6.90 - 1992 39.8 79.7 1990 18.1 1968 1991 CALENDAR YEAR 16938. 46. 641 9. 14 33600 6. 91. 93 29 17 2 4 Nov 8 2 Apr 30 Apr 27 75 58 28 24 19 17 17 16 39 60 119 37 40 52 52 35 29 20 31 132 73 34 24 22 21 20 20 19 19 19 23 92 --- 1153 38.4 132 16 2290 5.59 6.23 754 375 75 50 42 273 90 54 59 60 64 39 34 31 30 135 39 33 30 28 26 25 284 104 50 122 43 27 24 46 27 3073 99.1 754 24 6100 14.4 16.62 135 160 52 54 37 67 54 36 24 148 73 77 57 45 30 176 83 56 54 47 88 51 75 48 51 45 62 47 46 45 —— 2023 67.4 176 24 4010 9.80 10.94 43 41 41 37 39 40 41 88 63 45 89 40 40 73 73 80 154 61 40 58 43 56 31 53 67 61 87 66 54 32 28 1764 56.9 154 28 3500 8.27 9.54 26 37 38 60 179 114 64 41 39 57 172 56 46 74 53 35 35 26 22 33 23 20 20 32 24 21 19 17 18 21 61 1483 47.8 179 17 2940 6.95 8.02 19 17 24 23 39 61 32 28 94 27 44 29 28 26 29 48 79 64 51 130 123 49 92 76 44 34 28 25 24 30 —— 1417 47.2 130 17 2810 6.87 7.66 , BY WATER YEAR (WY) 41.7 83.1 1973 14.5 1984 FOR 1992 21470 58. 754 16 19 10300 10. 12 42590 8. 116. Ill 40 20 68.8 147 1970 18.7 1973 WATER YEAR 7 May 1 Apr 6 Feb 29 May 1 30 May 1 Apr 7 53 09 57.1 112 1970 12.4 1985 49.6 93.4 1969 20.5 1971 WATER 57 78 41 2780 6 9 20500 13 5 41850 8 114 104 33 16 55.1 81.4 1988 28.0 1985 YEARS 1967 - .8 .0 .2 Sep 18 .9 Apr 20 .4 Jun 12 Sep 18 .19 Sep 18 . 1 Apr 8 .40 .09 57.2 166 1989 26.6 1986 1992 1971 1972 1989 1970 1985 1989 1989 1970 354 RIO HAMEYBS BASIN 50065500 RIO MAMEYES NEAR SABANA, PR--Continued WATER QUALITY RECORDS PERIOD OP RECORD.--WATER YEARS JUNE 1983 TO CURRENT YEAR DATE TIME MAR. 10 1210 APR. 09 1015 STRBAMPLOW, INSTANTANEOUS (CPS) 20.1 29.1 SPECIFIC CON- DUCTANCE (UMHOS) 80 80 TEMPERA- TURE (DBG C) 23.5 22.5 STRBAMFLOW, DATE TIME INSTANTANEOUS (CPS) MAY 21 1230 •TON. 11 1337 25.9 46.9 SPECIFIC CON- DUCTANCE (UMHOS) 100 110 TEMPERA- TURE (DBG C) 25.5 25.0 355 RIO SABANA BASIN 50067000 RIO SABANA AT SABANA, PR LOCATION.--Lat 18°19'52", long 65°43'52", Hydrologic Unit 21010005, on right bank along Highway 988, 0.3 mi (0.5 km) north of junction of Highways 988 and 983 in Sabana, and 3.3 mi (5.3 km) south of Luguillo. DRAINAGE AREA.--3.96 mi> (10.26 km>)• WATER-DISCHARGE RECORDS PERIOD OF RECORD.--October 1979 to current year. GAGB.--Water-stage recorder and crest-stage gage. Elevation of gage is 260 ft (80 m), from topographic map. REMARKS.--Records fair except those for estimated daily discharges, which are poor. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY NOV JAN FBB MAR APR JUN JUL AUQ SEP 1 16 e!5 2 12 e8.7 3 9.0 7.3 4 8.4 6.1 5 12 e!9 6 7.9 42 7 6.6 e!44 8 6.5 e235 9 25 e!51 10 12 52 11 8.3 19 12 24 e!6 13 12 e!6 14 7.7 e!4 15 6.9 15 16 6.2 19 17 5.9 15 18 6.1 12 19 14 ell 20 7.9 ell 21 6.3 e74 22 6.2 152 23 6.8 22 24 6.1 20 25 5.4 16 26 5.1 17 27 4.9 23 28 4.9 17 29 6.5 16 30 5.7 14 31 4.9 —— TOTAL 277.2 1199.1 MEAN 8.94 40.0 MAX 25 235 MIN 4.9 6.1 AC-FT 550 2380 CFSM 2.26 10.1 IN. 2.60 11.26 e Estimated 13 16 65 25 19 15 13 16 14 14 12 14 14 14 12 19 12 12 12 36 16 12 11 10 10 10 10 10 10 9.9 11 486.9 15.7 65 9.9 966 3.97 4.57 STATISTICS OF MONTHLY MEAN DATA MEAN 22.7 32.5 MAX 66.4 79.7 (WY) 1986 1988 MIN 6.48 8.15 (WY) 1983 1981 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN- DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 24.2 64.1 1982 3.92 1990 FOR 10 9.5 9.5 9.3 436 95 24 17 35 89 24 20 27 17 16 15 15 13 13 12 12 12 11 11 11 11 10 11 10 9.3 8.7 1023.3 33.0 436 8.7 2030 8.34 9.61 FOR WATER 12.6 33.0 1992 6.12 1986 8.4 8.3 8.7 32 11 35 14 10 9.2 11 8.6 8.0 7.4 9.5 7.5 7.2 7.3 7.2 7.3 7.8 6.6 7.3 7.7 6.6 6.5 8.6 9.1 8.6 6.2 ___ --- 292.6 10.1 35 6.2 580 2.55 2.75 YEARS 1980 11.7 22.2 1988 2.94 1983 5.8 5.4 5.3 5.7 5.0 5.1 25 18 6.3 5.4 4.8 5.3 6.3 6.8 12 5.3 13 9.4 6.0 6.0 4.9 7.5 9.7 5.6 4.5 5.0 5.2 9.4 6.5 12 11 243.2 7.85 25 4.5 482 1.98 2.28 - 1992 12.7 36.0 1987 3.78 1980 1991 CALENDAR YEAR 5412. 14. 328 1. 2. 10740 3. 50. 25 6. 3. 6 8 Jun 30 5 Apr 30 0 Apr 25 74 85 6 4 6.1 5.5 4.2 4.0 4.0 3.9 5.3 11 42 11 6.6 8.7 10 4.8 3.9 2.7 9.4 49 16 7.9 4.6 4.1 3.4 2.9 2.7 2.5 2.4 2.2 5.7 29 --- 275.5 9.18 49 2.2 546 2.32 2.59 372 199 20 14 12 50 16 12 11 11 10 8.6 8.1 7.9 7.9 15 8.5 7.5 7.1 6.9 6.6 6.5 160 50 20 150 21 12 9.9 17 9.0 1266.5 40.9 372 6.5 2510 10.3 11.90 85 195 42 20 15 14 15 12 11 74 18 86 25 15 12 66 19 16 15 18 25 17 22 16 16 14 16 13 13 13 938 31.3 195 11 1860 7.90 8.81 12 11 11 11 11 10 10 15 13 11 19 10 9.4 16 12 9.8 29 11 10 21 15 18 12 17 16 11 19 15 13 10 9.8 418.0 13.5 29 9.4 829 3.41 3.93 9.8 10 9.9 13 36 28 20 13 12 21 66 18 13 16 13 12 11 9.9 9.6 11 9.9 8.6 8.7 9.4 47 13 9.5 8.8 8.6 8.5 17 501.2 16.2 66 8.5 994 4.08 4.71 8.2 9.2 8.3 7.4 8.5 11 8.3 11 40 9.3 12 7.7 6.8 7.1 7.5 12 29 18 10 37 85 15 29 19 12 10 9.6 8.9 8.7 11 476.5 15.9 85 6.8 945 4.01 4.48 , BY WATER YEAR (WY) 12.9 33.5 1990 2.20 1984 FOR 1992 7398 20 436 2 2 9600 19 1 14670 5 69 29 11 5 35.3 63.9 1982 14.8 1990 WATER YEAR .0 .2 Jan 5 .2 Apr 28 .9 Apr 22 Jan 5 . 74 Jan 5 .9 Apr 28 .10 .50 .7 22.0 50.6 1987 4.70 1985 14.5 31.3 1989 5.84 1986 WATER 19 28 11 887 1 9600 19 14250 4 67 37 8 2 17.7 32.7 1988 6.39 1985 YEARS 1980 .7 .2 .9 Sep .96 Apr .0 Apr Jan .74 Jan .86 Apr .97 .49 .6 .9 16.7 56.3 1989 7.23 1987 - 1992 1988 1984 18 1989 10 1983 6 1983 5 1992 5 1992 17 1983 356 RIO SABANA BASIN 50067000 RIO SABANA AT SABANA, PR—Continued WATER QUALITY RECORDS PERIOD OF RECORD.--WATER YEARS AUGUST 1981 TO CURRENT YEAR STRBAMFLOW, SPECIFIC CON- TEMPERA- DATE TIME INSTANTANEOUS DUCTANCB TURB (CFS) (UMHOS) (DBG C) STRBAMFLOW, SPECIFIC CON- DATE TIMS INSTANTANEOUS DUCTANCB MAR. 10 1022 APR. 09 0810 5.89 6.60 110 110 24 .0 23.5 MAY 21 0945 JUN. 11 1123 (CFS) 7.23 16.3 (UMHOS) 100 90 TEMPERA- TURE (DBG C) 25.0 25.0 RIO FAJARDO BASIN 357 50071000 RIO FAJARDO NEAR FAJARDO, PR LOCATION.--Lat 18°17'56", long 65°41'42", Hydrologic Unit 21010005, on left ban* off Highway 976, 0.1 mi (0.2 km) upstream from Highway 977 bridge, 0.3 mi (0.5 km) downstream from Quebrada Peflon, 1.1 mi (1.8 km) northeast of Colonia Paraiso, and 3.3 mi (5.3 km) southwest of Fajardo. DRAINAGE AREA.--14.9 mi> (38.6 km>). HATER-DISCHARGE RECORDS PERIOD OF RECORD.--1960-61 (occasional low and peak-flow measurements only), March 1961 to current year. GAGE.--Hater-stage recorder and crest-stage gage. Datum of gage is 137.60 ft (41.940 m) above mean sea level. Due to flood damage, gage datum has had changes as follows: Mar. 24, 1961 to May 5, 1969, 138.95 ft (42.352 m); May 6, 1969 to Mar. 16, 1972, 135.05 ft (41.163 m); Mar. 17, 1972 to Mar 25, 1975, 138.60 ft (42.245 m) . REMARKS.--Records fair except those for estimated daily discharges, which are poor. Low flow affected by diversions for water supply about 400 m upstream from gaging station (estimated mean daily discharges is 9.0 ft'/a (0.255 m'/a) Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY NOV DEC JAN APR MAY JUN JUL AUG SEP 1 41 55 2 37 32 3 25 26 4 22 15 5 38 44 6 20 110 7 15 241 8 21 724 9 30 302 10 19 177 11 17 77 12 52 59 13 27 54 14 16 47 15 14 43 16 12 57 17 11 41 18 20 33 19 40 30 20 19 30 21 13 129 22 13 225 23 67 63 24 17 71 25 13 43 26 11 37 27 9.8 51 28 8.5 48 29 10 76 30 13 70 31 8.2 TOTAL 679.5 3010 MEAN 21.9 100 MAX 67 724 MIN 8.2 15 AC-FT 1350 5970 CFSM 1.47 6.73 IN. 1.70 7.51 e Estimated STATISTICS OF MONTHLY MEAN MEAN 99.4 106 MAX 260 295 (WY) 1971 1975 MIN 19.1 30.8 (WY) 1969 1981 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 49 62 145 90 56 35 27 39 29 28 23 41 26 35 20 42 22 23 19 75 43 17 14 13 13 13 11 10 11 12 17 1060 34.2 145 10 2100 2.29 2.65 DATA 79.6 237 1976 14.9 1990 FOR 16 13 11 10 e860 e!50 e60 e35 e50 e250 e66 e54 e80 e38 e33 e31 e31 e25 e25 e23 e23 e24 e22 e23 e22 e23 e20 e23 e!9 e!7 e!5 2092 67.5 860 10 4150 4.53 5.22 FOR WATER 45.0 101 1969 15.4 1977 el4 e!4 e!5 ellO e21 ellO e35 el9 e!7 e23 e!5 e!4 e8.8 8.0 8.3 7.6 7.1 7.0 11 9.6 7.5 11 8.0 7.1 7.2 12 14 11 7.0 ___ --- 559.2 19.3 110 7.0 1110 1.29 1.40 YEARS 1961 37.7 80.4 1982 10.8 1983 5.7 5.7 5.8 5.7 6.4 5.6 e40 77 22 16 14 e42 33 41 e56 e24 e!6 e40 e!8 20 12 44 30 12 9.2 8.9 11 9.6 9.3 59 45 743.9 24.0 77 5.6 1480 1.61 1.86 - 1992 36.2 109 1987 9.70 1977 1991 CALENDAR YEAR 13254. 36. 724 5. 6. 26290 2. 33. 66 19 9. 1 3 Nov 8 5 Aug 14 5 Aug 9 44 09 1 21 12 6.3 4.8 4.0 4.9 17 13 297 63 47 17 21 14 12 8.0 123 206 262 65 18 13 11 e9.8 e8.8 eS.O e7.6 e6.8 e!4 e50 --- 1365.0 45.5 297 4.0 2710 3.05 3.41 e254 394 41 18 12 237 56 19 e!6 e!5 e!4 e!3 ell elO e9.6 e24 e!9 e!7 e!6 17 15 16 420 287 346 478 83 40 28 51 37 3013.6 97.2 478 9.6 5980 6.52 7.52 270 404 119 37 19 41 36 e!8 elO 213 52 104 29 18 14 e60 18 10 8.2 7.9 22 8.9 32 8.8 8.4 7.4 9.7 7.4 6.3 5.7 --- 1604.7 53.5 404 5.7 3180 3.59 4.01 5.1 4.9 4.9 4.7 5.1 4.4 4.2 8.9 8.0 4.8 6.8 4.9 4.7 9.4 5.3 7.4 73 18 14 26 12 19 9.5 e22 e23 e!5 e25 e!5 e9.2 7.3 6.2 387.7 12.5 73 4.2 769 .84 .97 6.0 11 15 9.3 106 117 30 37 16 19 127 48 e20 e32 e29 25 25 20 15 28 25 14 14 38 69 27 19 14 18 48 77 1098.3 35.4 127 6.0 2180 2.38 2.74 23 17 24 20 44 46 22 20 85 26 63 22 15 12 14 63 61 79 58 230 217 64 100 43 35 33 28 23 19 79 --- 1585 52.8 230 12 3140 3.55 3.96 , BY WATER YEAR (WY) 46.2 129 1963 4.02 1984 FOR 1992 17198 47 860 4 4 23300 19 34110 3 42 86 20 7 97.1 399 1979 17.7 1973 WATER YEAR .9 .0 Jan 5 . 0 Apr 5 . 8 Jul 1 Jan 5 . 88 Jan 5 .15 .94 .5 61.9 166 1962 10.0 1985 50.5 132 1969 12.5 1992 WATER 67 140 38 8800 1 1 23500 20 49040 4 61 129 34 12 58.9 159 1979 26.8 1985 YEARS 1961 - .7 .2 Sep 18 .0 May 6 .5 Apr 18 Sep 18 .00 Sep 18 .86 May 3 .54 .73 87.4 421 1989 19.1 1991 1992 1979 1972 1989 1984 1984 1989 1989 1984 358 RIO FAJARDO BASIN 50071000 RIO FAJARDO NEAR FAJARDO, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--Wat«r y«ar« 1960 to currant y«ar. WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 OCT 01 DEC 10 PEB 24 APR 06 JUN 09 AOG 18 OCT 01 DEC 10 FEB 24 APR 06 JUN 09 AOG 18 OCT 01 DEC 10 FEB 24 APR 06 JUN 09 AOG 18 K = DATE TIMS 1991 0950 1145 1992 1115 1340 1030 1000 STREP- TOCOCCI FECAL, (COLS. DATE PER 100 ML) 1991 420 250 1992 80 310 K50 60 CHLO- RIDE, DIS- SOLVED DATE (MG/L AS CL) 1991 . .. 12 ... 1992 ... 15 ... 12 non- ideal count DIS- CHARGE, INST. CUBIC FEET PER SECOND 33 31 7.9 4.0 10 19 HARD- NESS TOTAL (MG/L AS CAC03) 25 -- -- 39 -- 29 FLOO- RIDB, DIS- SOLVED (MG/L AS F) 0.20 -- -- <0.10 -- <0.10 SPE- CIFIC CON- DOCT- ANCE (OS/CM) 98 118 130 138 125 108 CALCIUM DIS- SOLVED (MG/L AS CA) 5.5 -- -- 8.2 -- 6.3 SILICA, DIS- SOLVED (MG/L AS SI02) 19 -- -- 24 -- 20 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.0 7.1 7.2 6.3 7.1 7.1 MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) 2.7 -- -- 4.5 -- 3.3 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 68 -- -- 87 -- 77 TEMPER- ATURE WATER (DBG C) 25.5 25.5 26.0 27.5 25.5 30.0 SODIUM, DIS- SOLVED (MG/L AS NA) 9.2 _- -- 12 _- 11 SOLIDS, DIS- SOLVED (TONS PER DAY) 5.99 -- -- 0.94 -- 3.95 TUR- BID- ITY (NTU) 4.3 3.3 1.0 0.80 1.7 24 SODIUM AD- SORP- TION RATIO 0.8 -- -- 0.8 -- 0.9 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 4 10 8 3 23 4 OXYGEN, DIS- SOLVED (MG/L) 7.8 6.2 9.0 8.6 8.6 7.6 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 1.2 -- -- 1.3 -- 1.0 NITRO- GEN, NITRITE TOTAL (MG/L AS N) •cO.010 •cO.010 <0.010 <0.010 <0.010 •cO.010 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 95 78 115 106 109 90 ALKA- LINITY WAT WH TOT FET FIELD MG/L AS CACO3 23 35 30 30 30 34 NITRO- GEN, N02+N03 TOTAL (MG/L AS N) 0.170 0.210 0.160 0.150 0.130 0.090 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) <10 59 <10 <10 <10 <10 SULFIDE TOTAL (MG/L AS S) <0.5 -- -- <o.s -- " NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.030 < 0.010 0.020 0.030 0.010 0.020 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K110 210 K10 250 230 50 SULFATB DIS- SOLVED (MG/L AS 804) 4.1 -- -- 3.8 -- 3.5 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) -- -- -- 0.17 -- -- RIO FAJARDO BASIN 50071000 RIO PAJARDO NEAR FAJARDO, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 359 DATE OCT 1991 01... DEC 10... PBB 1992 24... APR 06... JUN 09... AUG 18... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) NITRO- GEN, TOTAL (MG/L AS N) NITRO- GEN, TOTAL (MG/L AS NO3) PHOS- PHORUS TOTAL (MG/L AS P) ARSENIC TOTAL (UG/L AS AS) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) BORON, TOTAL RECOV- ERABLE (UG/L AS B) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) COPPER, TOTAL RECOV- ERABLE (UG/L AS CO) <0.20 <0.20 <0.20 0.20 <0.20 <0.20 0.35 1.5 0.030 0.020 <0.010 <0.010 <0.010 0.010 <1 <1 <100 <100 <1 <1 <1 <1 DATE OCT 1991 01... DEC 10... PBB 1992 24... APR 06.. . JUN 09... AUG 18.. . DATE JUN 1992 09... IRON, TOTAL RECOV- ERABLE (UG/L AS PB) LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) SELE- NIUM, TOTAL (UG/L AS SB) SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CYANIDE TOTAL (MG/L AS CN) PHENOLS TOTAL (UG/L) MBTHY- LENE BLUB ACTIVE SUB- STANCE (MG/L) 420 90 TIME 1030 <1 50 10 PCB, TOTAL (UG/L) ALDRIN, TOTAL (UG/L) <0.010 <0.10 <0.10 <1 <1 <1 <1 PESTICIDE ANALYSES CHLOR- DANE, TOTAL (UG/L) DDD, TOTAL (UG/L) DDE, TOTAL (UG/L) 20 <0.010 <0.010 DDT, TOTAL (UG/L) DI- AZINON, TOTAL (UG/L) <1 0.02 0.02 DI- BNDO- BLDRIN SULPAN, TOTAL TOTAL (UG/L) (UG/L) <0.010 <0.010 <0.010 <0.01 <0.010 <0.010 DATE JUN 1992 09... BNDRIN WATER UNPLTRD BTHION, RBC TOTAL (UG/L) (UG/L) HBPTA- HBPTA- CHLOR CHLOR, BPOXIDB LINDANB TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) <0.010 <0.01 <0.010 <0.010 <0.010 MALA- THION, TOTAL (UG/L) <0.01 MBTH- OXY- CHLOR, TOTAL (UG/L) <0.01 METHYL PARA- THION, TOTAL (UG/L) <0.01 MIREX, TOTAL (UG/L) <0.01 DATE JUN 1992 09... PARA- THION, TOTAL (UG/L) NAPH- THA- LENES, POLY- CHLOR. TOTAL (UG/L) PBR- THANE TOTAL (UG/L) TOX- APHENB, TOTAL (UG/L) TOTAL TRI- THION (UG/L) 2,4-D, TOTAL (UG/L) 2,4,5-T TOTAL (UG/L) 2, 4-DP TOTAL (UG/L) SILVBX, TOTAL (UG/L) <0.01 <0.10 <1 <0.01 <0.01 •cO.Ol <0.01 <0.01 360 RIO FAJARDO BASIN 50072500 RIO PAJARDO BELOW FAJARDO, PR WATER-QUALITY RECORDS LOCATION.--Lat 180 19'35", long 65 038'47", 1.2 ml (1.9 km) southwest of Playa de Pajardo, and east of Pajardo plaza. DRAINAGE AREA.--23.4 mi 1 (60.6 km'). PERIOD OP RECORD.--Water years 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 0.5 mi (0.8 km) DATE OCT 1991 01. .. DEC 10. .. PEB 1992 24. .. MAY 13. .. JUN 09. .. AOG 18... TIME 1235 1330 1235 0930 1135 1145 DIS- CHARGE, INST. CUBIC FEET PER SECOND 25 24 18 22 17 35 SPE- CIFIC CON- DUCT- ANCE (US /CM) 135 147 196 124 135 148 PH WATER WHOLE FIELD (STAND- ARD UNITS) 6.8 7.0 7.0 6.4 7.1 7.0 TEMPER- ATURE WATER (DEC C) 27.0 26.0 26.0 27.5 29.5 29.8 TUR- BID- ITY (NTU) 34 4.0 2.1 1.0 3.0 3.1 OXYGEN, DIS- SOLVED (MG/L) 7.0 6.5 8.5 6.4 8.2 7.9 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 83 82 96 80 91 88 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 16 11 <10 12 <10 <10 COLI- PORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K8700 400 720 360 2800 490 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 3100 200 800 510 260 20 DATE OCT 1991 01.. . DEC 10. .. FEB 1992 24.. . MAY 13... JUN 09.. . AUG 18.. . HARD- NESS CALCIUM TOTAL DIS- (MG/L SOLVED AS (MG/L MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L CACO3) AS CA) AS MG) AS NA) 35 8.4 3.3 13 31 6.8 3.3 11 37 8.5 3.8 13 ALKA- SODIDM POTAS- LINITY AD- SIUM, WAT WH SORP- DIS- TOT PET SULPIDB TION SOLVED FIELD TOTAL RATIO (MG/L MG/L AS (MG/L AS K) 1.9 0.9 1.2 0.9 1.1 35 23 34 23 40 18 CHLO- SULFATB RIDE, DIS- DIS- SOLVED SOLVED (MG/L (MG/L CAC03 AS S) AS SO4) AS CD <0.5 5.6 17 <0.5 4.4 14 4.3 20 OCT 01 DEC 10 PEB 24 MAY 13 JUN 09 AUG 18 K = FLUO- RIDE, DIS- SOLVED DATE (MG/L AS F) 1991 0.20 ... 1992 0.20 . . . <0.10 non- ideal count SILICA, SUM OF DIS- ( SOLVED TOENTS, (MG/L AS SIO2) 19 21 20 IS, IF 'I- 'S, :- ED L) 89 76 93 SOLIDS, DIS- SOLVED (TONS PER DAY) 6.13 — — 4.51 — 8.79 RESIDUE TOTAL AT 105 DEC. C, SUS- PENDED (MG/L) 18 11 14 12 <1 <1 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.220 — — — — __ NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.030 <0.010 <0.010 <0.010 <0.010 <0.010 NITRO- GEN, N02+N03 TOTAL (MG/L AS N) 0.250 0.100 0.110 <0.050 0.120 0.056 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.130 0.020 0.030 0.030 0.040 0.040 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.37 — — — — — RIO FAJARDO BASIN 50072500 RIO FAJARDO BELOW FAJARDO, PR—Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 361 DATE OCT 1991 01.. . DEC 10.. . FEB 1992 24.. . MAY 13. .. JUN 09... AUG 18.. . DATE OCT 1991 01.. . DEC 10. .. FBB 1992 24.. . MAY 13.. . JUN 09. . . AUG 18.. . NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.50 <0.20 <0.20 <0.20 <0.20 <0.20 IRON, TOTAL RECOV- ERABLE (UG/L AS FE) NITRO- GEN, TOTAL (MG/L AS N) 0.75 -- -- — — -- LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N03) 3.3 -- -- -- -- -- MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.060 0.020 0.030 0.030 0.010 0.060 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) ARSENIC TOTAL (UG/L AS AS) <1 -- -- <1 -- -- SELE- NIUM, TOTAL (UG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 -- — <100 — -- SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) -- -- -- 20 -- -- ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 — — <1 — -- CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) 2 -- -- <1 -- -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) <10 — — <10 — — METHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 1900 130 <1 130 30 <0.10 <0.10 20 •cO.010 •cO.010 <1 <1 0.03 0.01 362 RIO BLANCO BASIN 50075000 RIO ICACOS NEAR NAGUABO, PR LOCATION.--Lat 18°16'38", long 65°47'09", Hydrologlc Unit 21010005, in Caribbean National Forest, off Highway 191, at Bl Yunque, 1.6 mi (2.6 km) upstream from confluence with Rio Cubuy, 2.8 mi (4.5 km) north of Florida, and 5.3 mi (8.5 km) northwest of Naguabo Plaza. DRAINAGE AREA.--1.26 mi 1 (3.26 km'). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--July 1945 to March 1953 (operated by Puerto Rico Water Resources Authority), annual maximum, water years 1953-62, annual low-flow measurements 1962-66, October 1979 to current year. GAGE.--Water-stage recorder, crest-stage gage and sharp-crested weir. Elevation of gage is 2,020 ft (616 m), from topographic map. REMARKS.--Records fair except those for estimated daily discharges, which are poor. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 e36 49 2 e25 17 3 e!3 9.6 4 e!3 8.0 5 e23 14 6 el2 43 7 e8.0 53 8 e7.5 152 9 e7.0 44 10 e8.8 20 11 e8.8 9.0 12 e23 9.0 13 ell 7.7 14 e7.4 7.0 15 e6.8 8.9 16 e6.2 10 17 e6.0 7.2 18 e5.8 6.3 19 e5.9 6.0 20 e6.0 5.9 21 e5.4 45 22 e5.4 34 23 e5.4 23 24 e5.1 14 25 e4.8 e7.0 26 e4.9 el2 27 e4.7 e!8 28 e4.5 el3 29 7.5 e9.6 30 4.7 ell 31 4.5 TOTAL 297.1 673.2 MEAN 9.58 22.4 MAX 36 152 MIN 4.5 5.9 AC-FT 589 1340 CFSM 7.61 17.8 IN. 8.77 19.88 e Estimated e6.9 el3 e25 e45 el9 e!3 e6.0 ell elO e9.6 e6.4 el4 el2 ell e7.0 e8.0 e6.8 e7.4 e7.0 e25 el4 e7.2 e6.8 e5.4 e4.8 e4.8 e5.8 e5.8 e6.0 e5.8 e5.0 334.5 10.8 45 4.8 663 8.56 9.88 STATISTICS OF MONTHLY MEAN DATA MEAN 16.3 18.6 MAX 32.1 46.8 (WY) 1986 1951 MIN 8.77 8.00 (WY) 1983 1948 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 15.4 31.3 1988 4.99 1990 FOR e5.8 e5.0 e4.6 e4.1 e36 el32 e26 e7.0 el3 elOO e!2 ell e50 el2 e7.8 e7.0 e6.2 6.0 5.7 5.6 5.6 5.5 5.3 5.9 7.7 7.0 5.5 8.2 5.9 5.2 5.1 523.7 16.9 132 4.1 1040 13.4 15.46 FOR WATER 12.6 26.9 1952 7.72 1987 4.8 4.8 4.8 5.4 4.8 16 7.3 5.8 6.0 8.6 5.5 5.2 5.1 4.9 4.9 4.8 5.0 5.4 6.0 5.1 4.9 8.4 5.2 5.3 5.2 7.0 5.9 4.8 4.5 ___ --- 171.4 5.91 16 4.5 340 4.69 5.06 YEARS 1945 13.5 44.0 1950 4.86 1983 4.2 4.1 3.9 4.1 4.1 4.1 75 13 4.7 4.3 4.3 24 5.7 8.0 5.7 4.0 10 21 8.0 5.9 4.6 8.7 7.4 4.4 4.2 3.8 3.7 3.6 3.4 21 6.9 289.8 9.35 75 3.4 575 7.42 8.56 - 1992 10.8 26.1 1949 3.90 1951 1991 CALENDAR YEAR 4123. 11. 152 3. 3. 8180 8. 121. 23 7. 4. 8 3 Nov 8 6 Aug 7 7 Aug 4 97 75 5 5 5.8 4.3 3.9 3.9 4.2 4.1 17 14 39 7.7 12 13 9.7 8.4 7.6 6.1 10 42 24 9.7 7.7 7.3 7.4 7.2 6.9 7.3 6.9 6.9 7.6 8.7 --- 320.3 10.7 42 3.9 635 8.47 9.46 102 40 9.8 8.9 9.0 161 17 12 16 12 13 11 10 9.9 9.9 44 11 10 10 9.8 9.4 9.2 69 29 25 31 11 11 10 11 13 754.9 24.4 161 8.9 1500 19.3 22.29 40 33 12 15 11 20 24 14 10 30 19 18 15 15 12 30 22 12 12 9.4 9.5 9.1 13 8.9 8.4 7.9 9.7 7.9 7.6 7.4 --- 462.8 15.4 40 7.4 918 12.2 13.66 7.3 6.8 6.4 6.4 6.7 6.2 6.0 14 9.2 7.0 9.6 7.2 10 9.8 9.0 10 33 12 10 13 10 9.3 8.2 15 10 9.3 9.9 8.3 8.2 6.6 6.6 301.0 9.71 33 6.0 597 7.71 8.89 6.8 9.7 7.8 13 54 34 13 8.8 6.1 7.5 26 6.6 13 20 7.4 8.3 7.0 5.6 5.2 6.7 4.9 4.7 5.1 6.3 4.8 5.8 5.2 4.4 4.1 6.5 16 334.3 10.8 54 4.1 663 8.56 9.87 6.2 5.5 7.8 8.8 12 9.2 7.8 5.9 11 5.6 7.5 5.5 5.3 5.6 7.8 15 14 14 14 44 19 8.6 16 11 7.1 5.7 5.1 4.8 4.9 9.0 303.7 10.1 44 4.8 602 8.03 8.97 , BY WATER YEAR (WY) 13.0 34.4 1950 4.77 1984 FOR 1992 4766 13 161 3 4 1260 6 2 9450 10 140 25 8 4 17.6 26.3 1948 10.7 1951 12.5 20.5 1987 5.19 1985 WATER YEAR .7 .0 .4 .1 .71 .9 .3 .73 .0 .8 May 6 Mar 29 Feb 29 May 6 May 6 Aug 29 14.0 38.8 1952 7.35 1991 WATER 14 21 11 470 1 2 2860 8 10630 11 158 30 8 4 14.8 24.5 1945 7.63 1991 YEARS 1945 .7 .0 .2 Sep .5 Mar .0 Apr Apr .96 Apr .6 .27 .2 .7 17.1 37.6 1989 7.03 1986 - 1992 1952 1984 18 1989 22 1946 7 1946 21 1983 21 1983 RIO BLANCO BASIN 50075000 RIO ICACOS NEAR NAGDABO, PR--Continued WATER QUALITY RECORDS PERIOD OF RECORD.--WATER YEARS AUGUST 1981 TO CURRENT YEAR DATE TIME MAR. 31 1150 MAY. 20 1236 STRBAMFLOW, INSTANTANBOOS (CFS) 4.83 9.87 SPECIFIC CON- DUCTANCE (DMHOS) 50 50 TEMPBRA- TORE (DBG C) 21.5 24.5 STRBAMFLOH, DATE TIME INSTANTANBOOS (CFS) JON. 12 1338 11.0 363 SPECIFIC CON- TBMPBRA- DOCTANCB (OHHOS) 40 TORE (DBG C) 24.0 364 THIS PAGE WAS LEFT BLANK INTENTIONALLY 0123456 KILOMETERS 1234 MILES J»*«t»ek i»"«*»"sct»<r _|«Jt_^W*»! jMiJMWf Jf CMM*. I Spttcc d^^y-—*- sr~^—*>JHr -v.!^'^'-^ Mop or*o^>- liland. «i*ia« \ f*fad f^ *6UAY4«,O%^\'- M 7 I / j'^>~2~ • \\ V&/J& Si1) ._^3 V ^V^ <• ^ J ..As i ^/ Crain^t bsun^df^ *i'o Si»si*s»sf (Nioua) basin EXPLANATION ±0920 SURFACE-WATER STATION AND NUMBER ^0835 QUALITY-OF-WATER STATION AND NUMBER • 96 WELL AND WELL NUMBER Figure 22.--Southeastern river basins the Rio Humacao to Rio Seco basins. co O) Ol 366 RIO HUMACAO BASIN 50081000 RIO HUMACAO AT LAS PIEDRAS, PR LOCATION.--Lat 18°10«27", long 650 52'11", Hydrologic unit 21010005, on left bank at downstream aide of bridge on Highway 921, 0.6 mi (1.0 km) southeast of junction with Highway 30, 0.8 mi (1.3 km) downstream from Quebrada Blanca and 0.8 mi (1.3 km) south of Las Piedras. DRAINAGE AREA.--6.65 mi 1 (17.22 km2 ). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—September 1958 to December 1967 (monthly discharge measurements), July 1974 to September 1977, October 1987 to current year. GAGE.—Water-stage recorder. Elevation of gage is 260 ft (79 m), from topographic map. Prior to July 1974, crest-stage gage at different datum. July 1974 to September 1977 at site 90 ft (27 m) upstream at present datum. REMARKS.--Records fair except those above 1,000 ft3/a (28.3 m'/a) and estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JDN SEP 1 20 9.1 2 46 10 3 21 10 4 15 14 5 13 11 6 12 13 7 12 96 8 11 597 9 12 92 10 22 47 11 56 25 12 14 20 13 15 18 14 13 15 15 15 14 16 15 14 17 15 13 18 13 13 19 13 13 20 11 12 21 11 15 22 10 38 23 11 19 24 11 56 25 10 23 26 9.8 16 27 9.9 26 28 9.7 17 29 9.7 16 30 9.6 14 31 9.3 —— TOTAL 475.0 1296.1 MEAN 15.3 43.2 MAX 56 597 MIN 9.3 9.1 AC-FT 942 2570 CFSM 2.30 6.50 IN. 2.66 7.25 e Estimated 13 13 17 19 14 13 12 12 12 12 11 12 11 11 10 15 11 10 10 11 11 9.9 10 9.7 9.4 9.4 9.3 9.2 9.8 9.3 12 358.0 11.5 19 9.2 710 1.74 2.00 STATISTICS OF MONTHLY MEAN DATA MEAN 35.3 44.6 MAX 74.9 126 (WY) 1975 1988 MIN 15.3 17.0 (WY) 1992 1990 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 36.3 112 1988 11.5 1992 FOR 11 10 9.3 9.0 365 e290 e35 21 18 19 16 15 15 14 13 13 13 12 12 13 12 12 12 13 13 13 12 12 12 12 11 1057.3 34.1 365 9.0 2100 5.13 5.91 11 11 11 13 11 22 14 12 11 14 12 11 11 11 13 11 11 10 10 9.7 9.7 9.7 9.9 10 9.9 9.5 9.7 9.7 9.4 --- 327.2 11.3 22 9.4 649 1.70 1.83 FOR WATER YEARS 1974 19.9 34.1 1992 10.8 1990 15.0 20.5 1988 11.0 1977 9.1 10 9.8 11 11 12 17 16 10 9.1 9.0 8.8 8.8 9.0 9.4 8.4 9.5 10 8.9 13 9.2 8.7 8.5 8.2 8.1 9.2 11 8.2 7.9 7.4 7.7 303.9 9.80 17 7.4 603 1.47 1.70 - 1992 11.7 16.4 1989 9.24 1977 1991 CALENDAR YEAR 5784. 15. 597 4. 5. 11470 2. 32. 19 9. 6. 7 8 Nov 8 9 Jun 17 9 Apr 27 38 36 8 6 8.3 9.0 8.0 7.7 7.5 9.1 11 8.1 8.0 7.7 8.5 15 13 9.7 11 7.8 8.7 17 16 33 11 9.1 8.1 8.0 7.5 7.4 7.1 7.4 7.1 7.1 --- 303.9 10.1 33 7.1 603 1.52 1.70 , BY WATER 9.27 13.1 1976 5.88 1977 7.8 20 9.0 7.7 7.1 13 11 10 8.1 7.7 10 8.4 7.4 7.5 10 11 10 8.1 7.7 7.4 7.4 6.9 147 157 226 466 32 23 19 18 17 1308.2 42.2 466 6.9 2590 6.35 7.32 YEAR (WY) 15.3 42.2 1992 7.26 1990 115 48 25 31 26 21 22 28 42 29 27 37 41 37 25 22 28 21 19 22 39 21 24 19 18 17 18 17 16 15 870 29.0 115 15 1730 4.36 4.87 15.3 29.0 1992 5.91 1977 FOR 1992 WATER YEAR 8641.6 23.6 597 6.9 7.3 3720 8.67 6.8 17140 3.55 48.34 31 14 8.5 Nov 8 May 22 Apr 25 May 26 May 26 May 22 15 15 15 14 25 16 15 17 17 15 18 16 14 14 14 14 47 18 23 25 18 65 20 19 19 16 17 16 15 15 15 602 19.4 65 14 1190 2.92 3.37 17.6 33.2 1989 7.95 1990 WATER 22 37 12 1670 2 2 20800 34 16530 3 46 34 14 6 16 17 16 17 65 22 36 29 20 24 20 29 20 19 18 21 21 17 16 33 21 17 19 24 17 17 16 16 16 14 19 672 21.7 65 14 1330 3.26 3.76 19.8 32.7 1977 9.45 1974 YEARS 1974 - .8 .6 .1 Nov 27 .2 Jul 15 .8 Jul 19 Sep 6 .40 Sep 6 .43 .61 .7 15 16 21 15 14 21 19 18 35 17 15 14 13 14 14 25 37 21 84 298 123 33 39 27 23 21 21 18 17 20 1068 35.6 298 13 2120 5.35 5.97 31.4 54.1 1975 10.0 1990 1992 1988 1990 1987 1974 1974 1960 1960 RIO HUMACAO BASIN S0082000 RIO HUMACAO AT HIGHWAY 3 AT HUMACAO, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°08'49', long 65°49'37-, at bridge on Highway 3, 300 ft (91 •) downstream froa Quebrada Mariana, and 0.4 mi (0.6 km) couth of Humacao. DRAINAGE AREA.--17.3 mi> (44.8 km 1 ). PERIOD OF RECORD.--Water year* 1958-66, 1969 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 367 DATE OCT 1991 22. .. DEC 12... FBB 1992 14. .. MAY 08. .. JUN 18. .. AUG 28. .. TIME 1210 1215 1250 1150 1340 1430 DIS- CHARGE, INST. CUBIC FEET PER SECOND 3.4 13 21 6.5 10 8.6 SPE- CIFIC CON- DUCT- ANCE (US/CM) 400 346 315 370 296 306 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.0 6.9 7.5 6.7 7.4 7.4 TEMPER- ATURE WATER (DBG C) 28.5 25.5 26.0 28.5 31.5 30.0 TUR- BID- ITY (NTU) 13 8.0 20 12 17 5.9 OXYGEN, DIS- SOLVED (MG/L) 2.4 4.3 6.2 5.1 6.1 5.2 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 31 47 83 61 80 64 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 61 31 18 18 14 64 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K600000 58000 27000 -- K8SOO 290000 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 300000 42000 7400 — K1000 6200 DATE OCT 1991 22... DEC 12... FBB 1992 14.. . MAY 08.. . JUN 18... AUG 28... HARD- NESS CALCIUM TOTAL DIS- (MG/L SOLVED AS (MG/L MAGNE- SIUM, DIS- SODIUM, DIS- SOLVED SOLVED (MG/L (MG/L CAC03) AS CA) AS MG) AS NA) 95 26 7.2 34 89 26 5.9 27 83 23 6.1 24 ALKA- SODIUM POTAS- LINITY CHLO- AD- SIUM, WAT WH SULFATB RIDE, SORP- DIS- TOT FBT SULFIDB DIS- DIS- TION SOLVED FIELD TOTAL SOLVED SOLVED RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L AS K) 3.4 2.2 2.8 CACO3 130 90 115 100 84 100 AS S) AS S04) AS CL) <0.5 14 <0.5 12 13 36 37 31 SOLIDS, RESIDUE DATE OCT 1991 22... DEC 12.. . FBB 1992 14.. . MAY 08... JUN 18... AUG 28... FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.10 -- -- 0.20 -- 0.10 SILICA, DIS- SOLVED (MG/L AS SI02) 37 -- -- 33 — 34 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 236 -- -- 203 -- 190 SOLIDS, DIS- SOLVED (TONS PER DAY) 2.18 -- -- 3.59 -- 4.41 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) <1 5 36 4 32 18 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 1.00 0.910 1.09 0.650 0.420 0.500 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.100 0.090 0.110 0.050 0.030 0.020 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 1.10 1.00 1.20 0.700 0.450 0.520 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 2.80 1.40 0.190 0.060 0.080 1.20 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 1.3 0.90 0.51 -- 0.22 0.60 K = non-ideal count 368 RIO HUMACAO BASIN 50082000 RIO HUMACAO AT HIGHWAY 3 AT HUMACAO, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 22.. . DEC 12.. . FEB 1992 14.. . MAY 08... JUN 18... AUG 28.. . NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 4.1 2.3 0.70 <0.20 0.30 1.8 NITRO- GEN, TOTAL (MG/L AS N) 5.2 3.3 1.9 -- 0.75 2.3 NITRO- GEN, TOTAL (MG/L AS N03) 23 15 8.4 -- 3.3 10 BARIUM, BORON, CADMIUM PHOS- TOTAL TOTAL TOTAL PHORUS ARSENIC RBCOV- RBCOV- RECOV- TOTAL TOTAL BRABLB BRABLB ERABLB (MG/L (UG/L (UG/L (UG/L (UG/L AS P) AS AS) AS BA) AS B) AS CD) 0.880 <1 <100 30 <1 0.570 0.440 0.240 <1 <100 40 <1 0.130 0.410 CHRO- MIUM, COPPER, TOTAL TOTAL RBCOV- RECOV- ERABLE ERABLB (UO/L (UO/L AS CR) AS CU) <1 10 __ __ <1 <10 __ — DATE OCT 1991 22.. . DEC 12. .. FBB 1992 14.. . MAY 08.. . JUN 18.. . AUG 28.. . IRON, TOTAL RECOV- ERABLE (UG/L AS FB) LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) SELE- NIUM, TOTAL (UG/L AS SB) SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CYANIDE TOTAL (MG/L AS CN) PHENOLS TOTAL (UG/L) MBTHY- LENB BLUE ACTIVE SUB- STANCE (MG/L) 490 560 250 150 0.20 •cO.10 17 •cO.010 •cO.010 10 0.22 0.06 RIO GUAYANBS BASIN 50083500 RIO GUAYANBS AT YABUCOA, PR WATBR-QUALITY RECORDS LOCATION.--Lat 18°03'33", long 65°54'03", at bridge on Highway 182, 1.4 mi (2.2 km) west-northwest of plaza. DRAINAGE AREA.--17.2 mi 1 (44.6 km1 ). PERIOD OF RECORD.--Hater years 1958-62, 1968-70, 1980 to current year. HATER-QUALITY DATA, HATER YEAR OCTOBER 1991 TO'SEPTEMBER 1992 369 Yabucoa DATE OCT 1991 22. .. DEC 12... FEB 1992 19. .. MAY 08. .. JUN 18. .. AUG 24. .. TIME 1000 1100 0935 1000 1135 1250 DIS- CHARGE, INST. CUBIC FEET PER SECOND 27 51 28 33 88 28 SPE- CIFIC CON- DUCT- ANCE (US/CM) 150 161 177 160 127 150 PH HATER WHOLE FIELD (STAND- ARD UNITS) 7.0 7.2 7.2 6.3 6.9 7.0 TEMPER- ATURE HATER (DBG C) 25.0 23.0 23.0 25.0 26.0 28.0 TUR- BID- ITY (NTU) 16 13 9.3 33 53 8.4 OXYGEN, DIS- SOLVED (MG/L) 3.0 2.2 8.4 6.9 6.4 6.9 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 36 66 92 90 74 81 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) <10 13 <10 16 14 <10 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 42000 K220 K990 2100 4100 K7400 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 210 K90 K90 3100 3300 2600 DATE OCT 1991 22. .. DEC 12... PBB 1992 19. .. MAY 08... JUN 18.. . AUG 24.. . HARD- NESS TOTAL (MG/L AS CALCIUM DIS- SOLVED (MG/L MAGNE- SIUM, DIS- SOLVED (MG/L SODIUM, DIS- SOLVED (MG/L SODIUM AD- SORP- TION RATIO POTAS- SIUM, DIS- SOLVED (MG/L ALKA- LINITY HAT WH TOT PET FIELD MG/L AS SULFIDB TOTAL (MG/L SULFATE DIS- SOLVED (MG/L CHLO- RIDE, DIS- SOLVED (MG/L CAC03) AS CA) AS MG) AS NA) 55 14 43 11 47 12 4.8 17 3.8 14 4.2 14 AS K) 1.4 0.9 1.9 0.9 1.4 CACO3 AS S) AS SO4) AS CL) 64 60 64 25 41 40 <0.5 <0.5 3.7 15 5.6 15 3.6 14 DATE OCT 1991 22... DEC 12.. . PBB 1992 19. .. MAY 08. . . JUN 18. .. AUG 24.. . PLUO- RIDE, DIS- SOLVED (MG/L AS P) <0.10 -- -- 0.20 -- 0.10 SILICA, DIS- SOLVED (MG/L AS SI02) 36 -- -- 32 -- 34 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 130 -- -- 98 -- 118 SOLIDS, DIS- SOLVED (TONS PER DAY) 9.39 -- -- 8.72 -- 8.92 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 4 8 12 26 71 30 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.230 1.19 -- 0.320 0.290 0.260 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.030 0.010 <0.010 0.030 0.030 0.020 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 0.260 1.20 0.810 0.350 0.320 0.280 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.090 <0.010 0.010 0.040 0.060 0.050 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.11 -- -- -- -- -- non-ideal count 370 RIO GUAYANES BASIN 50083500 RIO GUAYANBS AT YABUCQA, PR—Continued HATER-QUALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATB OCT 1991 22... DEC 12... FBB 1992 19... HAY 08.. . JON 18... AOG 24... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L NITRO- GEN, TOTAL (MG/L NITRO- GEN, TOTAL (MG/L PHOS- PHORUS TOTAL (MG/L ARSENIC TOTAL (UG/L AS N) 0.20 <0.20 <0.20 <0.20 <0.20 <0.20 AS N) AS N03) AS P) 0.46 2.0 0.060 0.280 0.060 0.060 0.070 0.040 BARIUM, BORON, CADMIUM TOTAL TOTAL TOTAL RBCOV- RECOV- RBCOV- BRABLE ERABLB BRABLB (UG/L (UG/L (UG/L AS AS) AS BA) AS B) <100 <100 20 AS CD) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) <1 DATE OCT 1991 22.. . DEC 12.. . FEB 1992 19.. . MAY 08.. . JUN 18.. . AUG 24. . . DATB JUN 1992 18.. . IRON, TOTAL RECOV- ERABLE (UG/L AS FB) LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS UN) MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) SELE- NIUM, TOTAL (UG/L AS SB) SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CYANIDE TOTAL (MG/L AS CN) PHENOLS TOTAL (UG/L) MBTHY- LBNE BLUE ACTIVE SUB- STANCE (MG/L) 1700 2000 TIME 1135 130 100 <0.10 <0.10 PESTICIDE ANALYSES PCB, TOTAL (UG/L) ALDRIN, TOTAL (UG/L) <0.010 CHLOR- DANE, TOTAL (UG/L) DDD, TOTAL (UG/L) DDE, TOTAL (UG/L) DOT, TOTAL (UG/L) <0.010 <0.010 DI- AZINON, TOTAL (UG/L) 0.02 0.02 DI- BNDO- BLDRIN SULFAN, TOTAL TOTAL (UG/L) (UG/L) <0.010 <0.010 <0.010 <0.01 <0.010 <0.010 DATB JUN 1992 18... BNDRIN HATER UNFLTRD BTHION, REC (UG/L) TOTAL (UG/L) HBPTA- HBPTA- CHLOR CHLOR, EPOXIDB LINOANB TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) <0.010 <0.01 <0.010 <0.010 <0.010 MALA- THION, TOTAL (UG/L) <0.01 MBTH- OXY- CHLOR, TOTAL (UG/L) <0.01 METHYL PARA- THION, TOTAL (UG/L) <0.01 MIRBX, TOTAL (UG/L) <0.01 DATB JUN 1992 18... PARA- THION, TOTAL (UG/L) <0.01 NAPH- THA- LENES, POLY- CHLOR. TOTAL (UG/L) <0.10 PER- TOX- THANB APHENE, TOTAL TOTAL (UG/L) (UG/L) TOTAL TRI- THION (UG/L) <0.01 2,4-D, TOTAL (UG/L) <0.01 2,4,5-T 2, 4-DP SILVEX, TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) <0.01 <0.01 <0.01 377 RIO GUAYANBS BASIN 50086500 RIO QUAYANKS ABOVE MOUTH AT PLAYA DE GUAYANBS, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°03'45", long 65°49'42", at old railroad crossing, 0.2 mi (0.3 km) from mouth, 0.4 mi (0.6 kn) we«t of PIaya de Guayanes, and 3.5 mi (5.6 km) northeast of Yabucoa plasa. DRAINAGE AREA.--34.0 mi 1 (88.1 km1 ). PERIOD OF RECORD.—Water years 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 28... DEC 17... FBB 1992 19. .. MAY 12... JUN 19. .. AUG 28... TIME 1135 1230 1140 1145 1045 1250 DIS- CHARGE, INST. CUBIC FEET PER SECOND 11 27 35 61 40 39 SPE- CIFIC CON- DUCT- ANCE (US/CM) 182 180 185 184 210 255 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.2 7.2 7.6 6.5 6.6 7.3 TEMPER- ATURE WATER (DBG C) 27.0 24.5 25.0 29.0 27.5 29.5 TUR- BID- ITY (NTU) 13 12 9.8 11 29 7.5 OXYGEN, DIS- SOLVED (MG/L) 7.8 8.1 7.5 5.4 4.4 7.2 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 97 99 90 72 62 86 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 10 11 14 16 26 <10 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K650 290 280 370 2800 480 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 320 570 250 290 350 330 DATE OCT 1991 28... DEC 17.. . FBB 1992 19.. . MAY 12... JUN 19... AUG 28... HARD- NESS CALCIUM TOTAL DIS- (MG/L SOLVED AS (MG/L MAGNE- SIUM, DIS- SODIUM, DIS- SOLVED SOLVED (MG/L (MG/L CACO3) AS CA) AS MG) AS NA) 56 14 5.0 18 48 12 4.3 16 62 16 5.3 18 ALKA- SODIUM POTAS- LINITY CHLO- AD- SIUM, WAT WH SULFATB RIDE, SORP- DIS- TOT FBT SULFIDB DIS- DIS- TION SOLVED FIELD TOTAL SOLVED SOLVED RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L AS K) 2.0 1.9 1.6 CACO3 AS S) AS SO4) AS CL) 54 46 62 57 66 40 <0.5 <0.5 5.4 17 5.2 16 5.5 16 SOLIDS, RESIDUE DATE OCT 1991 28... DEC 17.. . FBB 1992 19... MAY 12... JUN 19... AUG 28... FLUO- RIDB, DIS- SOLVED (MG/L AS F) <0.10 -- -- 0.20 -- 0.10 SILICA, DIS- SOLVED (MG/L AS SIO2) 39 -- -- 36 — 34 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 133 -- -- 126 -- 135 SOLIDS, DIS- SOLVED (TONS PER DAY) 3.84 -- -- 20.6 -- 14.2 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 29 14 22 8 48 4 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.210 0.370 — -- 0.260 0.290 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.010 0.010 •cO.010 0.010 0.040 0.010 NITRO- GEN, N02+N03 TOTAL (MG/L AS N) 0.220 0.380 0.370 <0.050 0.300 0.300 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.030 •cO.010 0.010 0.030 0.170 0.050 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) -- — -- -- 0.53 — non-ideal count 372 RIO GDAYANES BASIN 50086500 RIO GDAYANES ABOVE MOUTH AT PLAYA DE GDAYANES, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 28... DEC 17.. . FBB 1992 19.. . MAY 12... JUN 19.. . AUG 28... DATE OCT 1991 28.. . DEC 17... FBB 1992 19.. . MAY 12.. . JUN 19.. . AUG 28... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) <0.20 <0.20 <0.20 <0.20 0.70 <0.20 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) — — — — 1.0 -- LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N03) -- -- -- -- 4.4 -- MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.080 0.040 0.040 0.020 0.250 0.030 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) ARSENIC TOTAL (UG/L AS AS) <1 -- -- <1 -- -- SELE- NIUM, TOTAL (UG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 — — <100 — -- SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) 80 -- -- 20 -- -- ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 — — <1 — -- CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (DG/L AS CR) 1 -- -- <1 — -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (DG/L AS CD) 20 — — <10 — — MBTHY- LBNE BLUB ACTIVE SUB- STANCE (MG/L) 1800 1100 90 90 <0.10 <0.10 <0.010 10 <0.010 0.02 0.02 RIO MAUNABO BASIN 50090500 RIO MAUNABO AT LIZAS, PR 373 LOCATION.--Lat 18°01'38-, long 65°56'24", Hydrologic Unit 21010005, on right bank, off Highway 759 at Lizas, about 1.0 mi (1.6 km) downstream from Quebrada Coroco, and about 3.0 mi (4.8 km) northwest of Haunabo. DRAINAGE AREA.--5.38 mi> (13.93 km»). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—February 1971 to January 1985, February 1991 to current year. GAGE.--Water-stage recorder and crest-stage gage. Elevation of gage IB 230 ft (70 m), from topographic map. REMARKS.--Recorda fair except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN SEP 1 17 18 2 138 9.3 3 21 6.6 4 14 6.4 5 12 8.1 6 10 10 7 8.9 120 8 8.8 506 9 46 107 10 13 60 11 13 34 12 11 31 13 10 26 14 9.1 22 15 11 21 16 9.2 19 17 12 18 18 13 16 19 8.9 16 20 7.7 16 21 7.3 35 22 6.8 24 23 6.8 39 24 6.6 115 25 6.5 28 26 6.2 39 27 6.0 56 28 5.9 31 29 6.0 32 30 5.9 23 31 5.4 TOTAL 463.0 1492.4 MEAN 14.9 49.7 MAX 138 506 MIN 5.4 6.4 AC-FT 918 2960 CPSM 2.78 9.25 IN. 3.20 10.32 e Estimated 22 22 56 42 25 21 e!9 e!7 e!6 IS 15 17 14 13 e20 14 12 11 11 11 11 10 10 9.6 9.3 9.3 9.5 9.1 8.8 10 32 521.6 16.8 56 8.8 1030 3.13 3.61 STATISTICS OF MONTHLY MEAN DATA MEAN 29.2 32.9 MAX 52.6 88.9 (WY) 1979 1978 MIN 12.7 7.46 (WY) 1982 1982 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK PLOW INSTANTANEOUS PEAK STAGE ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CPSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 18.4 35.2 1978 8.87 1981 34 13 10 9.3 289 212 32 20 18 21 16 14 13 11 10 9.7 8.9 8.2 7.7 7.5 7.3 6.8 7.0 9.1 7.8 7.6 6.5 6.4 6.0 5.9 6.0 840.7 27.1 289 5.9 1670 5.04 5.81 FOR WATER 12.8 27.1 1992 7.79 1981 6.2 6.4 6.7 7.2 7.2 16 8.8 7.7 7.1 7.6 6.7 7.0 6.3 11 7.6 7.0 6.3 6.6 6.1 5.9 6.0 7.9 6.2 7.5 6.5 7.8 6.6 5.9 5.6 ___ --- 211.4 7.29 16 5.6 419 1.35 1.46 5.3 5.8 5.8 6.7 6.3 7.4 28 20 7.3 6.3 5.9 5.6 5.6 5.7 5.8 5.2 6.7 6.1 5.3 5.1 .8 .6 .8 .8 .4 .4 .3 .0 .0 3.8 5.3 206.1 YEARS 1971 - 11.0 24.5 1982 6.10 1979 FOR 1992 7321. 20. 506 3. 4. 3030 11. 6.65 28 3.8 409 1.24 1.43 1992 9.69 18.9 1976 4.32 1979 4.6 4.4 4.1 3.9 3.8 4.9 4.7 4.1 4.0 3.9 6.0 24 6.4 36 10 5.7 5.0 9.0 64 25 8.8 6.4 5.2 .8 .5 .3 .3 .1 5.2 5.9 --- 287.0 9.57 64 3.8 569 1.78 1.98 , BY WATER 7.22 10.8 1976 3.92 1979 6.1 7.5 4.1 3.6 3.6 9.8 6.4 5.0 4.1 7.5 7.2 4.7 3.9 17 12 50 11 6.1 5.0 4.4 4.2 4.0 152 76 24 94 6.9 7.9 15 26 18 607.0 19.6 152 3.6 1200 3.64 4.20 YEAR (WY) 13.6 25.1 1979 5.13 1974 26 15 13 69 15 17 13 13 16 36 17 48 39 23 21 33 35 20 16 14 71 17 14 14 12 12 12 11 11 10 683 22.8 71 10 1350 4.23 4.72 17.9 47.1 1979 4.40 1974 WATER YEAR 7 0 6 2 14 Nov 8 May 4 Apr 4 Jan 5 Jan 5 14520 3. 50. 32 11 5. 72 63 1 9.9 9.2 9.2 9.0 13 11 11 16 15 13 22 11 10 11 11 11 14 14 15 14 31 26 14 14 15 14 12 10 9.8 9.0 9.6 413.7 13.3 31 9.0 821 2.48 2.86 17.1 35.4 1979 3.70 1974 WATER 18 36 12 2480 2 2 6780 14 13410 3 46 33 11 5 12 13 12 11 123 21 33 21 18 20 18 19 18 18 16 18 19 17 16 19 16 15 17 24 12 13 13 12 12 12 19 627 20.2 123 11 1240 3.76 4.34 24.9 131 1979 6.18 1974 YEARS 1971 .5 .7 .1 Aug .2 Jul .8 Jul Nov . 84 Nov .44 .74 .2 21 15 17 14 13 18 15 13 30 24 13 11 12 12 12 15 e28 e!7 e60 e290 e!70 e44 e22 e!6 e!4 e!2 ell elO elO e9.8 968.8 32.3 290 9.8 1920 6.00 6.70 25.8 81.5 1979 7.99 1980 - 1992 1979 1977 31 1979 16 1974 11 1974 25 1977 25 1977 374 RIO MAUNABO BASIN 50091000 RIO MAUNABO AT MAUNABO, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°00'24*, Iona 65°54'19*, at bridge on Highway 3, 0.4 mi (0.6 km) southwest of Haunabo plaza, and 1.3 mi (2.1 km) upstream from mouth. DRAINAGE AREA.--12.4 mi 1 (32.1 km 1 ). PERIOD OF RECORD.--Water years 1958-66, 1975 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 25. .. DSC 17. .. PBB 1992 18. .. MAY 12. .. JUN 17. .. AUG 26. .. TIME 1140 1105 1130 0945 1135 1145 DIS- CHARGE, INST. CUBIC FEET PER SECOND 2.1 0.98 11 4.3 47 4.5 SPE- CIFIC CON- DUCT- ANCE (US/CM) 320 247 273 317 190 230 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.2 7.1 7.8 6.8 7.0 7.1 TEMPER- ATURE WATER (DBG C) 28.5 23.5 24.5 25.5 27.0 29.5 TUR- BID- ITY (NTU) 18 3.9 19 7.5 130 12 OXYGEN, DIS- SOLVED (MG/L) 7.2 8.6 7.7 8.2 6.3 7.0 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 92 101 84 95 70 79 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 17 14 <10 16 36 14 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 23000 540 2200 3100 K71000 29000 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) K63 370 620 2000 43000 520 DATE OCT 1991 25... DEC 17.. . FBB 1992 18.. . MAY 12.. . JUN 17.. . AUG 26.. . HARD- NESS TOTAL (MG/L AS CALCIUM DIS- SOLVED (MG/L MAGNE- SIUM, DIS- SOLVED (MG/L SODIUM, DIS- SOLVED (MG/L SODIUM AD- SORP- TION RATIO POTAS- SIUM, DIS- SOLVED (MG/L ALKA- LINITY WAT WH TOT FBT FIELD MG/L AS SULFIDE TOTAL (MG/L SULFATB DIS- SOLVED (MG/L CHLO- RIDE, DIS- SOLVED (MG/L CAC03) AS CA) AS MG) AS NA) 97 23 90 22 69 17 9.5 27 8.5 27 6.5 19 AS K) 2.2 2.4 1.4 CACO3 110 90 120 92 60 70 AS S) AS S04) AS CL) <0.5 15 29 <0.5 17 36 8.1 20 SOLIDS, RESIDUE DATE OCT 1991 25.. . DEC 17.. . FEB 1992 18.. . MAY 12. .. JUN 17.. . AUG 26.. . FLUO- RIDE, DIS- SOLVED (MG/L AS F) 0.20 -- -- 0.10 -- 0.10 SILICA, DIS- SOLVED (MG/L AS SI 02) 39 -- -- 39 — 32 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 211 -- -- 207 -- 151 SOLIDS, DIS- SOLVED (TONS PER DAY) 1.22 -- -- 2.38 -- 1.83 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 18 1 28 12 348 20 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.230 -- 0.410 0.850 0.320 0.230 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.050 <0.010 0.010 0.110 0.060 0.010 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 0.280 0.370 0.420 0.960 0.380 0.240 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 1.00 <0.010 0.040 0.310 0.120 0.050 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.30 -- — 0.19 0.48 0.15 non-ideal count RIO MAUNABO BASIN 50091000 RIO MAUNABO AT MAUNABO, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 375 OCT 1991 25.. . DEC 17... FBB 1992 18.. . MAY 12.. . JUN 17.. . AUG 26.. . DATE OCT 1991 25.. . DEC 17... FBB 1992 18.. . MAY 12.. . JUN 17.. . AUG 26... NITRO- GEN, AM- MONIA 4 ORGANIC TOTAL (MG/L AS N) 1.3 <0.20 <0.20 0.50 0.60 0.20 IRON, TOTAL RECOV- ERABLE (UG/L AS FE) NITRO- GEN, TOTAL (MG/L AS N) 1.6 — — 1.5 0.98 0.44 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N03) 7.0 -- -- 6.5 4.3 1.9 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.550 0.030 0.090 0.780 0.140 0.070 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) ARSENIC TOTAL (UG/L AS AS) <1 -- -- <1 -- -- SELE- NIUM, TOTAL (UG/L AS SE) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 — — <100 — -- SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) 60 -- -- 50 -- -- ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 — -- <1 — -- CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) 1 -- -- <1 -- -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) 20 — — <10 — -- MBTHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 2200 640 180 90 <0.10 <0.10 10 10 <0.010 <0.010 0.03 0.04 376 RIO CHICO BASIN 50091800 RIO CHICO AT PROVIDBNCIA, PR HATER-QUALITY RECORDS LOCATION.—Lat 17°59'16", long 66°00'18-, at flat low bridge 200 ft (61 m) south of Highway (0.8 km) above mouth, and 1.5 mi (2.4 km) southeast of Patillaa plaza. DRAINAGE AREA.--4.9 mi 1 (12.8 km1 ). PERIOD OF RECORD.--Hater years 1979 to current year. HATER-QUALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 3, 0.5 mi DATE OCT 1991 04... DEC 09. .. PBB 1992 18. .. APR 06... JUN 17. .. AUG 25. .. TIME 1035 1045 1030 1140 1030 1030 DIS- CHARGE, INST. CUBIC FEET PER SECOND 3.4 0.86 1.9 0.46 20 0.67 SPE- CIFIC CON- DUCT- ANCE (US/CM) 327 370 396 519 238 330 PH HATER WHOLE FIELD (STAND- ARD UNITS) 7.4 7.7 7.5 7.0 7.2 7.8 TEMPER- ATURE HATER (DBQ C) 29.0 24.5 25.5 31.0 27.5 26.3 TUR- BID- ITY (NTU) 3.0 2.1 9.5 6.5 120 3.5 OXYGEN, DIS- SOLVED (MG/L) 4.3 8.9 6.6 6.4 6.7 7.0 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 55 96 84 85 87 89 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MQ/L) <10 19 28 31 40 12 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 2100 290 27 -- K130000 290 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 370 K64 290 -- K66000 200 DATE OCT 1991 04.. . DEC 09... FBB 1992 18.. . APR 06.. . JUN 17... AUQ 25.. . HARD- NESS CALCIUM TOTAL DIS- (MG/L SOLVED AS (MG/L MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L CAC03) AS CA) AS MG) AS NA) 98 23 9.9 34 87 23 7.1 61 94 22 9.4 30 SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY CHLO- SIUM, HAT HH SULFATB RIDE, DIS- TOT FET SULFIDE DIS- DIS- SOLVED FIELD TOTAL SOLVED SOLVED (MG/L MG/L AS (MG/L (MG/L (MG/L AS K) 1 2.6 3 11 1 2.3 CACO3 200 125 88 64 70 100 AS S) AS S04) AS CL) <0.5 19 <0.5 42 16 32 36 29 DATE OCT 1991 04.. . DEC 09... FBB 1992 18... APR 06.. . JUN 17.. . AUG 25... FLUO- RIDB, DIS- SOLVED (MG/L AS P) 0.10 -- -- 0.10 -- 0.20 SILICA, DIS- SOLVED (MG/L AS SI02) 32 -- -- 25 — 31 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 273 _- -- 274 -- 206 SOLIDS, DIS- SOLVED (TONS PER DAY) 2.47 __ -_ 0.34 -- 0.37 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 5 14 16 17 230 11 NITRO- GEN, NITRATE TOTAL (MG/L AS N) -- 1.38 3.86 9.58 0.550 1.98 NITRO- GEN, NITRITE TOTAL (MG/L AS N) <0.010 0.020 0.040 0.120 0.020 0.020 NITRO- GEN, N02+N03 TOTAL (MG/L AS N) 1.10 1.40 3.90 9.70 0.570 2.00 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.040 0.030 0.050 0.230 0.070 0.040 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.36 0.27 1.2 4.1 1.0 0.26 non-ideal count RIO CHICO BASIN 50091800 RIO CHICO AT PROVIDENCIA, PR—Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 377 DATE OCT 1991 04... DEC 09.. . FBB 1992 18... APR 06.. . JUN 17.. . AUG 25... DATE OCT 1991 04. .. DEC 09... FBB 1992 18... APR 06... JUN 17.. . AUG 25... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.40 0.30 1.3 4.3 1.1 0.30 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) 1.5 1.7 5.2 14 1.7 2.3 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N03) 6.6 7.5 23 62 7.4 10 MANGA- NESE, TOTAL RECOVr BRABLB (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.830 1.20 3.40 8.70 0.440 0.810 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) ARSENIC TOTAL (UG/L AS AS) <1 -- -- 1 -- -- SELE- NIUM, TOTAL (UG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 — -- <100 — -- SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) -- -- -- 150 -- -- ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 — — <1 -- -- CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) <1 -- -- <1 -- -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) <10 — — 10 — -- MBTHY- LBNB BLUB ACTIVE SUB- STANCE (MG/L) 200 470 30 40 <0.10 0.10 <1 30 <0.010 <0.010 0.07 0.23 375 RIO GRANDE DE PATILIAS BASIN 50092000 RIO GRANDE DE PATILLAS NEAR PATILLAS, PR—Continued (National stream-quality accounting network station) LOCATION.--Lat 18°02'04", long 66°01'58", Hydrologic Unit 21010004, on left bank, at foot bridge, off Highway 184, 1.2 mi (1.9 km) upstream from Lago Patillas Dam and 2.2 mi (3.5 km) northwest of Patillas. DRAINAGE AREA.--18.3 mi' (47.4 km9 ). WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1960 to current year. WATER-QOALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 03... JAN 1992 28... APR 16... JUL 13. .. DATE OCT 1991 03... JAN 1992 28. .. APR 16. .. JUL 13. .. DATE OCT 1991 03... JAN 1992 28. .. APR 16. .. JUL 13. .. TIME 1000 1050 0950 1045 CALCIUM DIS- SOLVED (MG/L AS CA) 10 14 13 12 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 97 112 110 117 DIS- CHARGE, INST. CUBIC FEET PER SECOND 72 33 9.7 31 MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) 4.1 5.5 5.0 4.7 SOLIDS, DIS- SOLVED (TONS PER DAY) 21.3 8.94 27.7 9.63 SPE- CIFIC CON- DUCT- ANCE (US/CM) 150 185 165 165 SODIUM, DIS- SOLVED (MG/L AS NA) 13 15 14 13 NITRO- GEN, NO2+NO3 DIS- SOLVED (MG/L AS N) 0.360 <0.050 0.190 0.190 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.0 7.5 7.1 6.7 SODIUM AD- SORP- TION RATIO 0.9 0.9 0.8 0.8 NITRO- GEN, AMMONIA DIS- SOLVED (MG/L AS N) 0.120 0.030 0.010 0.030 TEMPER- ATURE WATER (DEG C) 25.0 27.0 23.5 26.5 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 1.0 0.80 0.80 0.60 NITRO- GEN, AMMONIA DIS- SOLVED (MG/L AS NH4) 0.15 0.04 0.01 0.04 TUR- BID- ITY (NTU) 5.3 1.4 1.5 1.0 ALKA- LINITY WAT WH TOT FET FIELD MG/L AS CAC03 40 54 50 64 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.90 0.20 <0.20 <0.20 OXYGEN, DIS- SOLVED (MG/L) 8.4 8.9 8.5 7.8 SULFATE DIS- SOLVED (MG/L AS SO4) 9.1 10 12 11 PHOS- PHORUS TOTAL (MG/L AS P) 0.020 0.010 <0.010 <0.010 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 92 101 99 88 CHLO- RIDE, DIS- SOLVED (MG/L AS CL) 12 13 15 13 PHOS- PHORUS DIS- SOLVED (MG/L AS P) 0.030 0.010 <0.010 <0.010 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K1400 490 K870 460 FLUO- RIDE, DIS- SOLVED (MG/L AS F) 0.10 0.20 0.20 <0.10 PHOS- PHORUS ORTHO, DIS- SOLVED (MG/L AS P) 0.030 0.020 0.020 0.020 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 29000 K170 2200 500 SILICA, DIS- SOLVED (MG/L AS SI02) 22 21 19 23 PHOS- PHATE, ORTHO, DIS- SOLVED (MG/L AS PO4) 0.09 0.06 0.06 0.06 HARD- NESS TOTAL (MG/L AS CACO3) 42 58 53 49 SOLIDS, RESIDUE AT 180 DEG. C DIS- SOLVED (MG/L) 110 100 97 117 ALUM- INUM, DIS- SOLVED (UG/L AS AL) 80 20 20 <10 K = non- ideal count RIO GRANOB DB PATILLAS BASIN 50092000 RIO GRANDE DB PATILLAS NEAR PATILLAS, PR--Continued (National stream-quality accounting network station) WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 379 DATE OCT 1991 03. .. JAN 1992 28. .. APR 16. . . JUL 13. .. BARIUM, COBALT, IRON, DIS- DIS- DIS- SOLVED SOLVED SOLVED (UG/L (UG/L (UG/L AS BA) AS CO) AS PB) 11 <3 81 15 <3 28 13 <3 19 13 <3 14 LITHIUM DIS- SOLVED (UG/L AS LI) <4 <4 <4 <4 MANGA- NESE, DIS- SOLVED (UG/L AS MN) 11 34 13 7 PARTICLE-SIZE DISTRIBUTION DATE OCT 1991 03. .. JAN 1992 28. . . APR 16. .. JUL 13. .. TIME 1000 1050 0950 1045 STREAM- PLOW, INSTAN- TANEOUS (CPS) 72 33 9.67 31 MOLYB- DENUM, DIS- SOLVED (UG/L AS MO) <10 <10 <10 <10 NICKEL, DIS- SOLVED (UG/L AS NI) 2 2 <1 <J- SELE- NIUM, SILVER, DIS- DIS- SOLVED SOLVED (UG/L (UG/L AS SB) AS AG) <1 <1.0 <1 «1.0 <1 <1.0 <1 <1.0 STRON- TIUM, DIS- SOLVED (UG/L AS SR) 36 51 45 42 VANA- DIUM, DIS- SOLVED (UQ/L AS V) <6 <6 <6 <6 OP SUSPENDED SEDIMENT SEDI- MENT, SUS- PENDED (MG/L) 322 34 26 11.8 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 62 3.02 0.68 0.99 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 99 88 98 86 380 THIS PAGE WAS LEFT BLANK INTENTIONALLY '"•-\ /~T^~*-" ' v.^yx..-^ ! \ EXPLANATION ^1080 SURFACE-WATER STATION T1065 QUALITY-OF-WATER STATION AND NUMBER :>Nirc 087 WELL AND WELL M <ttGT-!i ^-"^^" \.| wrvn ^-'-^s \.^ "" T -,' i' ^r v \ ViU.ALBAJ ^.J- / ,/• — ....... Safna d? Jotoos "^^ '" 0123456 KILOMETERS ..i Figure 23-South coast river basins the Rio Salinas to Rio Jacaguas basins. CO 00 382 RIO SALINAS BASIN 50100200 RIO LAPA NEAR RABO DEL BUBY, PR LOCATION.--Lat 18°03'36", long 66°14'28". Hydrologic Unit 21010004, on left bank, at bridge on Highway 1, Km 9.7, 1.5 mi (2.4 km) north of Rabo del Buey, and 4.4 mi (7.1 km) northeast of Salinas Plaza. DRAINAGE AREA.--9.92 mi 1 (25.69 km3 ). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--1953-63 (annual low-flow measurements only), September 1988 to current year. GAGE.—Water-stage recorder and crest-stage gage. Elevation of gage is 394 ft (120 m), from topographic map. REMARKS.--Records fair. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR MAY JUN JUL ADO 1 .87 1.2 2 .94 1.3 3 .93 .98 4 .91 .84 5 . 8 ) .83 6 . £ 3 .83 7 .92 27 8 1.4 11 9 1.4 2.7 10 1.1 1.3 11 1.0 .90 12 .93 .76 13 .94 .74 14 .88 .71 15 .84 .65 16 .84 .61 17 .83 .63 18 .84 .69 19 .86 .64 20 6.2 .65 21 1.6 .69 22 9.4 .79 23 1.1 .78 24 .82 .97 25 .82 1.0 26 .80 1.1 27 .75 1.3 28 .83 1.3 29 1.3 1.2 30 2.2 1.1 31 1.3 TOTAL 45.27 65.19 MEAN 1.46 2 . 17 MAX 9.4 27 MIN .75 .61 AC-FT 90 129 CFSM .15 .22 IN. .17 .24 1.0 .98 .96 1.0 .95 .94 .95 .95 .90 .86 .78 .77 .76 .79 .78 .80 .80 .81 .82 .88 .97 .95 1.0 1.0 1.0 1.0 1.1 1.2 1.3 1.3 1.4 29.70 .96 1.4 .76 59 .10 .11 STATISTICS OF MONTHLY MEAN DATA MEAN 23.3 9.32 MAX 76.1 28.4 (WY) 1991 1991 MIN 1.46 2.17 (WY) 1992 1992 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN- DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 2.50 6.09 1991 .96 1992 FOR 1.4 1.4 1.4 1.4 1080 517 171 98 56 42 26 13 9.3 11 12 10 8.6 10 11 9.2 7.7 7.1 5.7 3.9 2.8 3.3 3.2 3.3 2.9 2.2 1.9 2133.7 68.8 1080 1.4 4230 6.88 7.94 2.5 3.1 2.7 1.7 1.9 3.1 3.4 2.5 2.5 2.5 2.6 2.5 2.4 2.7 2.4 2.7 2.4 2.2 2.4 2.2 2.5 2.5 2.7 2.2 2.2 2.3 2.5 3.6 2.5 ___ --- 73.4 2.53 3.6 1.7 146 .25 .27 FOR WATER YEARS 1988 18.6 68.8 1992 .56 1990 4.24 12.4 1991 .49 1990 2.5 2.5 2.8 2.8 2.8 2.6 2.3 1.7 1.6 1.9 2.2 2.1 2.1 1.9 1.9 1.7 1.7 1.8 2.2 2.1 2.6 2.4 1.8 1.7 1.8 1.6 1.6 1.5 1.5 1.6 3.2 64.5 2.08 3.2 1.5 128 .21 .24 - 1992 1.25 2.08 1992 .44 1990 1991 CALENDAR YEAR 820.56 2.25 74 .16 .19 1630 .22 3.05 3.4 1.0 .37 Feb 12 Jul 23 Jul 21 1.7 2.5 2.0 1.9 1.8 1.8 1.7 1.9 2.0 1.9 1.7 2.1 1.9 2.1 2.2 2.3 1.6 1.3 3.1 26 5.8 3.3 2.3 2.2 2.4 2.6 2.5 2.4 2.6 2.6 --- 92.2 3.07 26 1.3 183 .31 .34 , BY WATER 1.16 3.07 1992 .28 1990 FOR 1992 4062 11 1080 15700 17 8060 1 15 7 2.5 2.1 1.8 1.9 1.8 2.9 2.0 1.6 1.4 1.4 1.2 1.2 1.0 9.6 3.3 2.1 1.9 1.7 1.4 1.3 1.4 1.3 76 113 60 760 26 15 13 12 12 1133.8 36.6 760 1.0 2250 3.66 4.22 YEAR (WY) 9.64 36.6 1992 .18 1990 11 10 9.0 8.1 7.5 7.1 6.8 6.2 5.8 5.3 7.4 8.0 6.8 6.7 6.4 6.4 5.9 5.8 6.0 5.7 6.0 5.4 5.1 .8 .7 .7 .5 .3 .2 .0 189.6 6.32 11 4.0 376 .63 .71 2.05 6.32 1992 .46 1989 WATER YEAR .39 .1 .61 .65 .82 .48 .11 .11 .8 Jan 5 Nov 16 Nov 15 Jan 5 Jan 5 Nov 20 1.9 .86 3.9 3.8 3.6 3.4 3.2 3.1 3.1 3.2 3.0 2.9 3.0 3.0 2.9 2.9 2.6 3.0 2.7 2.5 2.3 1.9 2.0 2.1 1.9 2.0 1.8 1.7 1.6 1.6 1.6 1.5 1.4 79.2 2.55 3.9 1.4 157 .26 .29 .99 2.55 1992 .14 1989 WATER 7 11 3 1080 15700 17 5210 9 11 1 1.3 1.4 1.4 1.3 50 7.0 3.5 2.9 2.6 2.5 2.5 2.5 2.2 2.1 2.1 2.1 2.0 1.9 1.9 1.9 1.7 1.7 1.8 1.7 1.6 1.6 1.5 1.5 1.5 1.5 1.5 112.7 3.64 50 1.3 224 .36 .42 2.62 6.06 1990 .18 1989 YEARS 1988 .20 .2 .13 Jan . 02 Aug . 07 Aug Jan .82 Jan .72 .78 .3 .21 1.5 1.4 1.3 1.2 1.3 1.2 1.2 1.1 1.1 1.1 .99 .97 .98 .94 .90 .85 .88 .84 .88 4.1 3.5 2.3 1.9 1.7 1.6 1.6 1.5 1.4 1.4 1.5 —— 43.13 1.44 4.1 .84 86 .14 .16 10.3 29.1 1989 .82 1991 - 1992 1991 1990 5 1992 29 1989 24 1989 5 1992 5 1992 RIO SALINAS BASIN 50100450 RIO MAJADA AT LA PLENA, PR 383 LOCATION.--Lat 18°02'40", long 66°12'2T, Hydrologic Unit 21010004, on right bank, upstream side of bridge on Hwy 712, about 0.3 mi (0.5 km) southwest of La Plena. DRAINAGE AREA.--16.7 mi> (43.3 km>). WATER-DISCHARGE RECORDS PERIOD OF RBCORD.—September 1988 to current year. GAGE.—Water-stage recorder. Elevation of gage is 410 ft (125 m), from topographic map. REMARKS.-Records fair except those for estimated daily discharges, which are poor. Some regulation at low flow upstrc from station by local residents for agricultural purposes. DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY -TON JUL AUG SEP 1 2.6 1.6 2 2.6 1.1 3 2.8 .97 4 2.0 .85 5 1.6 .91 6 1.4 .90 7 1.3 25 8 1.3 32 9 1.5 21 10 2.7 6.3 11 1.8 3.3 12 1.4 2.3 13 1.2 1.8 14 .97 1.4 15 .98 1.1 16 1.0 .90 17 .94 .97 18 .94 .88 19 .95 .78 20 .97 .79 21 1.1 .70 22 .88 .87 23 .77 .98 24 .85 2.7 25 .94 3.1 26 .85 1.9 27 .84 3.2 28 .75 4.5 29 .69 4.1 30 1.9 3.3 31 3.7 --- TOTAL 44.22 130.20 MEAN 1.43 4.34 MAX 3.7 32 MIN .69 .70 AC-FT 88 258 CFSM .09 .26 IN. .10 .29 e Estimated STATISTICS OF MONTHLY MEAN MEAN 22.3 10.4 MAX 76.4 25.2 (WY) 1991 1991 MIN 1.43 2.15 (WY) 1992 1990 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN- DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 2.3 2.7 2.8 5.4 4.6 3.3 2.6 2.3 1.9 1.8 1.6 1.5 1.5 1.3 1.3 1.4 1.2 .88 .80 .85 1.8 1.2 .95 .95 1.0 .93 .91 .96 1.0 .98 1.2 53.91 1.74 5.4 .80 107 .10 .12 DATA 4.17 9.67 1991 1.22 1990 FOR 2.1 2.4 2.2 1.9 e!520 e450 18 12 9.7 7.8 7.0 7.7 7.3 5.7 5.5 5.4 5.3 5.1 5.1 4.9 .8 .6 .6 .9 .7 .6 .1 .0 3.9 3.6 3.4 2132.3 68.8 1520 1.9 4230 4.12 4.75 FOR WATER 19.5 68.8 1992 .98 1990 3.3 3.2 3.3 3.4 3.2 4.6 4.8 4.1 3.5 3.5 3.4 3.2 3.1 3.0 3.1 3.0 2.7 2.8 2.7 2.4 2.4 2.3 2.4 2.6 2.9 2.9 2.9 2.9 2.6 ___ --- 90.2 3.11 4.8 2.3 179 .19 .20 YEARS 1989 4.83 12.1 1991 .63 1990 2.4 2.3 2.3 2.2 2.3 2.3 2.2 2.5 2.5 2.4 2.2 2.3 2.2 2.1 2.4 2.3 2.3 2.6 2.7 2.9 2.8 2.8 2.7 2.9 3.1 3.1 3.2 3.3 3.1 3.1 3.4 80.9 2.61 3.4 2.1 160 .16 .18 - 1992 2.36 3.92 1991 .59 1990 1991 CALENDAR YEAR 1186. 3. 57 . 2350 . 2. 5. 1. . 84 25 Feb 12 56 Aug 20 61 Sep 1 19 64 5 8 77 4.8 7.0 3.9 2.5 2.1 2.1 2.4 2.6 2.4 2.4 2.4 5.2 5.2 4.0 5.4 3.3 2.4 2.2 3.0 16 8.3 3.5 2.6 2.3 2.1 2.0 2.1 2.0 1.9 2.6 110.7 3.69 16 1.9 220 .22 .25 2.5 2.8 2.3 1.9 1.6 2.0 2.6 2.2 1.8 1.6 1.7 1.8 1.5 6.8 11 3.3 2.5 1.9 1.7 1.7 1.7 1.6 32 56 31 496 31 25 22 20 18 789.5 25.5 496 1.5 1570 1.53 1.76 17 16 16 15 14 13 13 13 12 13 14 21 18 16 13 11 11 9.9 9.1 8.6 17 12 9.7 8.7 7.9 7.3 6.9 6.6 6.3 5.7 361.7 12.1 21 5.7 717 .72 .81 5.6 5.5 5.3 5.0 5.8 5.0 4.7 4.8 5.2 4.9 5.6 5.3 4.5 4.1 4.2 8.1 6.2 5.2 .6 .3 .2 .5 .5 .2 .0 3.9 3.8 3.7 3.6 3.6 3.4 147.3 4.75 8.1 3.4 292 .28 .33 3.4 3.5 4.5 3.5 77 31 12 7.2 5.8 5.4 5.4 5.5 4.9 4.8 5.1 4.5 4.3 4.0 3.9 4.3 3.7 3.4 3.2 3.2 3.2 3.5 3.8 3.5 5.3 3.5 3.6 239.9 7.74 77 3.2 476 .46 .53 4.1 3.9 5.1 3.4 3.1 3.0 3.2 3.0 3.5 3.1 2.3 2.2 2.3 2.1 1.8 2.0 3.1 2.8 2.8 67 48 22 14 10 7.9 7.0 6.8 6.0 4.7 5.0 —— 255.2 8.51 67 1.8 506 .51 .57 , BY WATER YEAR (WY) 1.97 3.69 1992 .58 1990 FOR 1992 4436 12 1520 15200 17 8800 9 13 3 1 7.33 25.5 1992 .25 1990 WATER YEAR .03 .1 Jan 5 .69 Oct 29 .81 Oct 23 Jan 5 . 19 Jan 5 .73 .88 .2 .0 3.79 12.1 1992 .53 1990 2.12 4.75 1992 .62 1989 WATER 7 12 1 1520 15200 17 5660 6 11 2 2.96 7.74 1992 .73 1989 YEARS 1989 .81 .1 .61 Jan . 05 Jun .05 Jun Jan .19 Jan .47 .36 .2 .49 11.6 30.1 1989 1.50 1991 - 1992 1992 1990 5 1992 4 1990 4 1990 5 1992 5 1992 384 RIO COAMO BASIN 50106500 RIO COAMO NEAR COAMO, PR HATER-QUALITY RECORDS LOCATION.--Lat 18°03'52", long 66°22'10", Hydrologic Unit 21010004, on Highway 153 bridge, 0.4 (0.6 km) above Rio de la Mina, and 1.8 mi (2.9 km) couth of Coamo plaza. DRAINAGE AREA.--46.0 mi' (119.1 km'). PERIOD OP RECORD.--Hater year* 1978 to current year. HATER-QUALITY RECORDS, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 03. .. JAN 1992 02... FBB 18. .. MAY 07.. . JUN 23... AUG 27.. . DATE OCT 1991 03.. . JAN 1992 02... FBB 18.. . MAY 07... JUN 23... AUG 27. .. DATE OCT 1991 03.. . JAN 1992 02... FBB 18... MAY 07.. . JUN 23... AUG 27.. . TIME 1445 1205 0820 1300 1330 1200 STREP- TOCOCCI FBCAL, (COLS. PER 100 ML) K160 710 290 500 20 310 FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.20 -- -- 0.20 -- <0.10 DIS- CHARGE, INST. CUBIC FBBT PBR SECOND 7.1 4.9 12 10 9.3 8.7 HARD- NESS TOTAL (MG/L AS CAC03) 260 — -- 250 -- 260 SILICA, DIS- SOLVED (MG/L AS SI02) 29 -- -- 26 -- 28 SPE- CIFIC CON- DUCT- ANCE (US/CM) 700 637 680 652 630 688 CALCIUM DIS- SOLVED (MG/L AS CA) 69 -- -- 70 -- 68 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 426 -- -- 381 -- 408 PH HATER WHOLE FIELD (STAND- ARD UNITS) 8.0 7.1 7.3 7.0 7.0 7.7 MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) 21 -- -- 19 -- 21 SOLIDS, DIS- SOLVED (TONS PBR DAY) 8.16 — -- 10.3 — 9.58 TEMPER- ATURE HATER (DBG C) 31.0 26.0 25.0 31.5 32.5 32.0 SODIUM, DIS- SOLVED (MG/L AS NA) 46 -- -- 38 -- 40 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 5 5 6 <1 10 8 TUR- BID- ITY (NTU) 2.6 4.2 1.3 1.3 1.5 1.0 SODIUM AD- SORP- TION RATIO 1 -- — 1 -- 1 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.550 0.980 0.870 0.820 2.01 1.26 OXYGEN, DIS- SOLVED (MG/L) 5.3 8.9 4.9 6.1 10.7 8.4 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 5.6 -- -- 4.5 -- 4.1 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.650 0.720 0.230 0.680 0.190 0.340 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 70 102 68 80 116 96 ALKA- LINITY HAT WH TOT FBT FIELD MG/L AS CAC03 270 180 260 210 240 220 NITRO- GEN, N02+N03 TOTAL (MG/L AS N) 1.20 1.70 1.10 1.50 2.20 1.60 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 31 13 10 25 20 <10 SULFATB DIS- SOLVED (MG/L AS S04) 37 -- -- 45 -- 54 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 4.30 1.00 1.10 1.20 0.800 0.610 COLI- FORM, FBCAL, 0.45 UM-MF (COLS./ 100 ML) 2100 590 270 30000 2100 2600 CHLO- RIDE, DIS- SOLVED (MG/L AS CL) 56 — — 52 -- 49 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 1.4 0.70 0.50 0.60 0.90 0.59 non-ideal count RIO COAMO BASIN 50106500 RIO COAMO NEAR COAMO, PR--Continued WATER-QUALITY RECORDS, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 385 DATE OCT 1991 03... JAN 1992 02.. . FBB 18.. . MAY 07.. . JUN 23. .. AUG 27. .. DATE OCT 1991 03.. . JAN 1992 02.. . FBB 18.. . MAY 07.. . JUN 23.. . AUG 27.. . NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 5.7 1.7 1.6 1.8 1.7 1.2 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) 6.9 3.4 2.7 3.3 3.9 2.8 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS NO3) 31 15 12 15 17 12 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 1.20 0.590 0.440 0.550 0.500 0.420 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) ARSENIC TOTAL (UG/L AS AS) 1 -- -- 1 -- -- SELE- NIUM, TOTAL (UG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 -- -- 100 -- -- SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) -- -- , -- 100 -- -- ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 -- -- <1 — -- CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) <1 -- -- <1 -- -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) 10 - — <10 — -- MBTHY- LENB BLOB ACTIVE SUB- STANCE (MG/L) 170 210 120 220 <0.10 <0.10 10 <0.010 <0.010 0.11 0.17 386 RIO DESCALABRADO BASIN 50108000 RIO DESCALABRADO NEAR LOS LLANOS, PR LOCATION.--Lat 18°03'08", long 66°25'34", Hydrologic Onit 21010004, at bridge on Highway 14, 1.5 mi (2.4 km) west of Los Llanos, and 5.3 mi (8.5 km) east of Juana Diaz. DRAINAGE AREA.--12.9 mi 1 (33.4 km 1 )- WATER-DISCHARGE RECORDS PERIOD OF RECORD. —1959-65 (annual low-flow measurements only), 1965 (annual maximum discharge), January 1966 to June 1969, July to December 1969 (maximum discharge only), February 1984 to current year. GAGE.—Water-stage recorder. Elevation of gage is 220 ft (67 m), from topographic map. REMARKS.--Records fair'except those for estimated daily discharges, which are poor. Some regulation at low flow by local resident upstream from station. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR MAY JDN JOL AOG SEP 1 8.2 3.5 2 9.7 elO 3 5.8 e4 . 5 4 4.7 e2 . 5 5 4.7 el. 5 6 4.0 el.l 7 3.5 el. 3 8 3.3 el.l 9 4.7 e3 . 5 10 6.0 e3.0 11 4.1 e2.0 12 3.4 el. 5 13 2.6 el.l 14 2.3 el.O 15 1.9 el.l 16 1.8 el.l 17 2.3 el.l 18 1.4 el.l 19 1.6 el. 2 20 15 el.l 21 7.5 1.1 22 7.5 1.9 23 11 1.8 24 3.2 2.2 25 2.3 2.0 26 1.7 1.8 27 1.6 3.2 28 1.3 3.2 29 1.6 2.3 30 1.5 1.4 31 7.6 TOTAL 137.8 65.2 MEAN 4.45 2 . 17 MAX 15 10 MIN 1.3 1.0 AC-FT 273 129 CFSM .34 .17 IN. .40 .19 e Estimated STATISTICS OF MONTHLY MEAN MEAN 29.2 17 . 2 MAX 117 41.0 (WY) 1986 1985 MIN 2.02 2.17 (WY) 1968 1992 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 1.4 1.3 1.7 2.0 1.6 1.4 1.3 .99 1.0 1.0 .97 .92 1.0 1.1 1.3 1.7 2.0 1.1 .85 .99 .96 .98 1.1 1.3 1.2 1.2 1.1 1.1 1.1 .95 1.0 37.61 1.21 2.0 .85 75 .09 .11 DATA 5.58 24.5 1988 .19 1968 FOR .96 .87 .79 .80 457 543 e45 e!8 e!2 elO e7.0 e5.6 e4.0 e3.2 e2.6 e2.2 el. 8 el. 5 1.1 1.0 1.0 .72 .67 .81 .80 .63 .75 .84 1.1 1.3 1.5 1128.54 36.4 543 .63 2240 2.82 3.25 FOR WATER 5.73 36.4 1992 .057 1968 1.6 2.1 1.9 2.3 2.8 7.2 7.4 5.4 2.5 2.5 2.8 4.2 2.5 2.4 2.2 2.0 1.9 2.0 1.9 1.5 1.4 1.2 1.3 1.6 1.4 1.6 2.0 2.3 2.0 --- 73.9 2.55 7.4 1.2 147 .20 .21 YEARS 1966 2.04 7.57 1986 .020 1968 1.9 2.3 2.2 1.9 1.8 2.1 2.0 1.5 1.3 1.4 1.4 1.3 1.3 1.6 1.5 1.4 1.9 1.7 1.3 1.5 3.4 3.9 2.4 2.2 2.1 1.9 1.6 1.7 1.8 1.8 1.8 57.9 1.87 3.9 1.3 115 .14 .17 - 1992 1.13 3.49 1986 .012 1968 1991 CALENDAR YEAR 1913. B. 138 . 3790 . 5. 9. 2. 06 24 Jul 16 23 Aug 10 28 Aug 7 41 52 5 0 47 45 17 7.9 5.0 4.0 5.5 5.0 3.0 2.6 2.1 1.9 3.9 2.9 3.9 7.7 4.1 7.0 4.8 8.3 34 55 13 8.4 10 12 8.4 7.3 6.6 6.5 e6.0 --- 308.8 10.3 55 1.9 613 .80 .89 e5.8 e5.4 e5.0 e4.7 elO e!6 elO eS.O e4.0 e3.8 elO e6.0 e4.2 e5.0 e5.6 e4.0 e2.9 2.2 1.1 1.2 .79 1.1 357 127 54 789 138 84 64 52 44 1822.79 58.8 789 .79 3620 4.56 5.26 74 48 40 34 27 21 17 22 18 13 9.9 9.5 7.5 7.2 6.4 5.4 5.6 5.7 5.4 5.6 8.1 6.0 6.4 4.8 2.4 1.7 1.1 1.3 1.6 2.1 417.7 13.9 74 1.1 829 1.08 1.20 4.0 2.2 2.2 2.0 1.3 1.1 1.3 1.2 1.3 1.7 1.8 2.2 3.0 2.9 2.3 1.8 2.1 3.9 5.4 3.3 3.9 4.3 3.3 3.0 2.3 2.3 2.1 1.6 1.2 1.1 4.2 76.3 2.46 5.4 1.1 151 .19 .22 6 2 1 1 49 22 10 8 8 7 6 6 4 3 2 2 1 1 2 1 1 1 1 1 1 1 1 1 1 1 1 162 5. 1 .1 .0 .6 .6 .3 .3 .8 .0 .6 .1 .1 .3 .1 .6 .8 .1 .5 .4 .6 .4 .0 .2 .1 .1 .1 .5 .6 .4 .3 24 49 .0 322 . • 41 47 e.72 e.70 e.68 e.68 e.66 .77 7.3 4.7 2.1 1.6 1.6 1.6 1.6 1.3 1.1 1.1 .87 .74 3.1 6.7 8.2 5.5 4.7 3.9 5.0 7.4 5.3 3.2 2.3 eS.O --- 93.12 3.10 8.2 .66 185 .24 .27 , BY WATER YEAR (WY) 3.92 18.8 1985 .000 1968 FOR 1992 4381 12 789 6020 13 8690 12 10 2 1 15.9 62.2 1985 .032 1968 WATER YEAR .96 .0 May 26 .63 Jan 26 .75 Jan 22 May 26 .46 May 26 .23 Jan 4 .93 .64 .2 .1 5.20 25.2 1987 .000 1967 2.39 10.5 1991 .000 1967 WATER 9 18 1 2600 30000 24 6800 9 13 1 3. 9. 51 11 1988 . 19 1990 YEARS .38 .4 .89 .00 .00 .37 .73 .88 .3 .00 1966 Oct Jun Jun Oct Oct 13.4 40.2 1985 .063 1967 - 1992 1986 1968 7 1985 22 1966 22 1966 7 1985 7 1985 RIO JACAGUAS BASIN 50110900 RIO TOA VACA ABOVE LAGO TOA VACA, PR 387 LOCATION.--Lat 18°07'37", long 66°27'24-, Hydrologic Unit 21010004, on right bank, off a dirt road about 0.3 mi (0.5 km) from road 553, 2.4 mi (3.9 km) southeast from Villalba plaza, and 0.2 mi (0.3 km) downstream from confluence with Quebrada Lim6n. DRAINAGE AREA.--7.64 mi* (19.79 km»). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--April 1989 to current year. GAGE.--Water stage recorder. Elevation of gage is 525 ft (160 m ), from topographic map. REMARKS.--Records fair. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JDN JUL ADG SEP 1 7.6 4.8 2 3.6 4.1 3 3.2 3.7 4 3.0 3.2 5 3.0 2.7 6 2.8 2.6 7 2.8 2.8 8 3.2 3.8 9 3.9 2.4 10 3.2 2.2 11 2.9 2.2 12 2.8 2.1 13 2.6 1.9 14 2.6 1.7 15 2.6 1.8 16 2.6 1.8 17 2.6 1.7 18 2.6 1.6 19 2.5 1.6 20 9.5 1.5 21 3.3 1.5 22 14 1.5 23 4.2 1.5 24 2.9 1.5 25 2.6 1.7 26 2.4 1.6 27 2.2 1.6 28 3.6 1.6 29 3.2 1.5 30 24 1.5 31 11 TOTAL 143.0 65.7 MEAN 4.61 2.19 MAX 24 4.8 MIN 2.2 1.5 AC-FT 284 130 CFSM .60 .29 IN. .70 .32 STATISTICS OF MONTHLY MEAN MEAN 54.3 18.2 MAX 109 40.1 (WY) 1991 1991 MIN 4.61 2.19 (WY) 1992 1992 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 1. 1. 1. 1. 1. 1. 1. 1. 1.2 1.3 1.3 1.4 1.4 1.4 1.4 1.4 1.5 1.5 1.3 1.3 1.6 1.5 1.5 1.5 1.5 1.6 1.6 1.4 1.4 1.4 1.3 43.9 1.42 1.6 1.2 87 .19 .21 DATA 5.93 11.2 1991 1.42 1992 FOR 1.3 1.2 .91 .85 676 381 42 28 22 17 16 22 15 10 7.9 13 16 6.9 5.7 5.6 5.2 .9 .6 .6 .3 .5 .0 3.7 3.6 3.7 3.8 1335.26 43.1 676 .85 2650 5.64 6.50 FOR WATER 17.2 43.1 1992 3.75 1990 3.6 3.5 3.4 3.2 3.2 7.7 7.4 8.7 5.3 4.4 4.1 4.6 3.6 3.5 3.4 3.3 3.3 3.2 3.2 3.1 2.9 3.6 3.9 2.8 2.8 3.0 2.9 2.8 2.6 ___ --- 113.0 3.90 8.7 2.6 224 .51 .55 YEARS 1989 3.68 4.75 1991 2.37 1990 2.6 2.5 2. 2. 2. 2. 2. 2.5 2.4 3.0 2.7 2.4 2.3 2.2 2.2 2.4 2.4 2.5 2.4 2.5 2.9 3.6 2.9 2.8 2.8 2.8 2.8 3.1 19 10 16 117.7 3.80 19 2.2 233 .50 .57 - 1992 3.39 4.71 1991 1.67 1990 1991 CALENDAR YEAR 1952. 5. 89 1. 1. 3870 . 9. 8. 3. 1. 7 35 May 20 2 Dec 9 3 Dec 5 70 51 4 2 6 17 11 7.4 5.0 4.1 3.9 3.6 3.5 3.2 5.6 4.2 4.0 3.6 3.4 3.8 17 26 13 21 62 39 21 13 9.2 6.9 5.7 5.1 4.5 4.1 4.4 --- 335.2 11.2 62 3.2 665 1.46 1.63 4.2 3.7 3.4 3.2 3.2 3.6 4.3 3.2 3.1 3.0 3.2 4.7 8.3 27 37 30 21 16 18 14 8.1 3.8 212 137 92 382 78 55 46 40 39 1307.0 42.2 382 3.0 2590 5.52 6.36 174 93 67 55 45 39 35 60 34 26 27 32 28 27 28 25 24 22 21 20 21 19 19 18 18 18 17 17 17 16 1062 35.4 174 16 2110 4.63 5.17 15 15 15 18 20 19 18 19 19 17 17 17 16 16 15 15 13 14 13 12 13 12 11 12 12 11 9.2 8.9 8.0 7.8 17 444.9 14.4 20 7.8 882 1.88 2.17 8.7 6.8 7.1 9.1 21 18 6.7 5.8 5.8 16 10 7.9 6.5 5.7 5.9 5.2 4.5 4.3 4.0 11 16 8.0 5.3 4.4 4.0 3.8 3.9 3.7 3.9 3.5 3.3 229.8 7.41 21 3.3 456 .97 1.12 3.2 3.0 3.0 3.0 3.0 3.4 4.5 31 15 4.9 3.4 2.8 2.7 2.4 2.3 2.5 2.9 2.6 2.4 3.8 4.2 3.0 3.4 4.6 3.6 3.7 3.2 3.1 6.3 62 198.9 6.63 62 2.3 395 .87 .97 , BY WATER YEAR (WY) 5.17 11.2 1992 1.46 1990 FOR 1992 5396 14 676 1 8700 13 10700 1 26 25 3 1 14.7 42.2 1992 1.42 1990 WATER YEAR .36 .7 Jan S . 85 Jan 4 .2 Dec 29 Jan S . 24 Jan 5 . 83 Jan 3 .93 .28 .9 .5 10.8 35.4 1992 1.23 1990 7.39 14.4 1992 .71 1990 WATER 14 18 10 676 8700 13 10460 1 25 32 3 1 6.96 11.9 1989 2.74 1990 YEARS 1989 .4 .2 .4 Jan .45 Aug .61 Jul Jan .24 Jan .44 Aug .89 .67 .5 .1 25.6 46.2 1989 6.63 1992 - 1992 1991 1990 5 1992 7 1990 9 1990 5 1992 5 1992 7 1990 388 RIO JACAOOAS BASIN 50110900 RIO TOA VACA ABOVE LAGO TOA VACA, PR—Continued HATER-QUALITY RECORDS PERIOD OF RECORDS.-- Water year* 1988 to 1992. PERIOD OF DAILY RECORD.-- SOSPBNDBD-SEDIMENT DISCHARGES April 1988 to September 1992. INSTRUMENTATION.-- Automatic «ediment sampler. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATIONS Maximum daily mean, 3,170 mg/L January 05, 1992; Minimum daily mean, 1 mg/L several day*. SEDIMENT LOADS: Maximum daily mean, 18,300 ton* (16,600 tonne*) January 05, 1992; Minimum daily 0.0 ton (0.0 tonne) several day*. EXTREMES FOR CURRENT YBAR.-- SBDIMENT CONCENTRATION* Maximum daily 1 mg/L several day*. an, 3,170 mg/L January 05, 1992; Minimum daily mean, SEDIMENT LOADS: Maximum daily mean, 18,300 ton* (16,600 tonne*) January 05, 1992; Minimum daily 0.0 ton (0.0 tonne) few day*. SEDIMENT DISCHARGE, SOSPBNDBD (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) OCTOBER 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 7.6 3.6 3.2 3.0 3.0 2.8 2.8 3.2 3.9 3.2 2.9 2.8 2.6 2.6 2.6 2.6 2.6 2.6 2.5 9.5 3.3 14 4.2 2.9 2.6 2.4 2.2 3.6 3.2 24 11 29 8 7 7 7 9 11 11 9 11 17 22 22 19 16 15 14 13 15 50 11 75 19 36 41 39 35 48 20 164 62 2.3 .08 .06 .06 .06 .07 .08 .09 .08 .09 .13 .16 .16 .13 .11 .10 .10 .10 .11 4.9 .11 19 .19 .27 .29 .26 .21 .54 .21 59 2.8 NOVEMBER 4.8 4.1 3.7 3.2 2.7 2.6 2.8 3.8 2.4 2.2 2.2 2.1 1.9 1.7 1.8 1.8 1.7 1.6 1.6 1.5 1.5 1.5 1.5 1.5 1.7 1.6 1.6 1.6 1.5 1.5 23 23 22 21 20 19 16 15 15 15 15 15 13 11 10 10 10 10 10 10 10 8 8 7 6 6 6 5 5 5 .33 .28 .27 .22 .18 .16 .12 .16 .10 .08 .08 .08 .07 .06 .05 .05 .04 .04 .04 .04 .04 .04 .04 .03 .02 .02 .02 .02 .02 .02 MEAN DISCHARGE (CFS) 1. 1. 1. 1. 1. 1. 1. 1. 1.2 1.3 1.3 1.4 1.4 1.4 1.4 1.4 1.5 1.5 1.3 1.3 1.6 1.5 1.5 1.5 1.5 1.6 1.6 1.4 1.4 1.4 1.3 MEAN CONCEN- TRATION (MG/L) DECEMBER 5 5 6 8 10 11 13 15 16 17 14 11 13 16 15 15 13 12 11 11 14 18 21 21 20 19 17 16 15 14 17 SEDIMENT DISCHARGE (TONS/ DAY) .02 .02 .02 .03 .04 .04 .05 .06 .05 .06 .05 .04 .05 .05 .05 .06 .05 .04 .04 .04 .06 .08 .08 .08 .08 .08 .07 .06 .06 .05 .08 TOTAL 143.0 91.85 65.7 2.72 43.9 1.64 RIO JACAGOAS BASIN 389 50110900 RIO TOA VACA ABOVE LAGO TOA VACA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN MEAN MEAN CONCBN- SEDIMENT MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) (CPS) (MG/L) (TONS/DAY) 1.3 1.2 .91 .85 671 381 42 28 22 17 16 22 15 10 7.9 13 16 6.9 5.7 5.6 5.2 .9 .6 .6 .3 .5 .0 3.7 3.6 3.7 3.8 JANUARY 15 15 15 15 3170 2540 279 85 25 9 9 13 19 24 27 68 70 25 25 24 23 22 23 24 15 25 24 20 17 18 21 FEBRUARY .05 .05 .04 .04 18300 8100 38 6.9 1.6 .43 .39 .77 .67 .63 .60 5.4 3.7 .45 .38 .35 .31 .29 .27 .28 .19 .29 .25 .19 .17 .18 .21 3.6 3.5 3.4 3.2 3.2 7.7 7.4 8.7 5.3 4.4 4.1 4.6 3.6 3.5 3.4 3.3 3.3 3.2 3.2 3.1 2.9 3.6 3.9 2.8 2.8 3.0 2.9 2.8 2.6 ___ ___ 24 28 33 35 28 16 14 14 16 16 15 14 14 21 32 44 29 51 45 38 38 47 54 48 33 20 14 10 9 ___ ___ .23 .26 .29 .30 .24 .34 .28 .33 .22 .19 .18 .17 .13 .19 .28 .38 .25 .44 .37 .30 .30 .45 .53 .36 .24 .15 .11 .08 .06 ..- MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) MARCH 2.6 2.5 2. 2. 2. 2. 2. 2.5 2.4 3.0 2.7 2.4 2.3 2.2 2.2 2.4 2.4 2.5 2.4 2.5 2.9 3.6 2.9 2.8 2.8 2.8 2.8 3.1 19 10 16 15 25 33 31 15 11 10 10 9 8 7 7 6 5 3 2 2 2 2 3 3 4 7 10 10 10 10 10 115 37 80 .10 .17 .21 .20 .10 .07 .06 .06 .06 .07 .05 .04 .03 .02 .02 .02 .02 .02 .02 .02 .03 .04 .06 .08 .08 .08 .08 .09 13 1.4 7.7 TOTAL 1330.26 26463.08 113.0 7.65 117.7 24.00 390 RI° JACAGOAS BASIN 50110900 RIO TOA VACA ABOVE LAGO TOA VACA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN DISCHARGE (CPS) 17 11 7.4 5.0 4.1 3.9 3.6 3.5 3.2 5.6 4.2 4.0 3.6 3.4 3.8 17 26 13 21 62 39 21 13 9.2 6.9 5.7 5.1 4.5 4.1 4.4 ___ MEAN CONCEN- TRATION (MG/L) APRIL 79 40 19 17 14 12 11 12 12 11 10 10 8 5 3 73 117 52 92 1090 93 15 10 5 3 4 5 8 11 15 ___ SEDIMENT DISCHARGE (TONS/DAY) 5.6 1.4 .41 .23 .16 .12 .10 .11 .10 .17 .10 .10 .08 .05 .04 9.1 9.8 2.3 7.3 510 12 .88 .38 .15 .06 .06 .07 .09 .12 .17 ___ MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MAY 4.2 3.7 3.4 3.2 3.2 3.6 4.3 3.2 3.1 3.0 3.2 4.7 8.3 27 37 30 21 16 18 14 8.1 3.8 212 137 92 380 78 55 46 40 39 17 15 14 13 11 82 4 2 2 2 6 15 17 167 183 149 96 66 116 73 30 12 1870 803 570 2650 457 333 222 205 188 .18 .15 .13 .11 .09 .72 .05 .02 .02 .02 .05 .37 .50 63 21 16 6.3 3.8 6.5 3.0 .75 .14 3760 312 147 10800 103 50 27 23 20 MEAN DISCHARGE (CPS) MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) JUNE 174 93 67 55 45 39 35 60 34 26 27 32 28 27 28 25 24 22 21 20 21 19 19 18 18 18 17 17 17 16 819 265 32 25 18 17 16 338 125 33 12 9 9 11 16 19 16 10 6 8 16 21 19 12 5 3 6 10 10 9 955 77 5.9 3.8 2.1 1.7 1.5 166 13 2.5 .84 .81 .69 .80 1.1 1.3 1.0 .59 .36 .46 .84 1.1 .95 .57 .24 .14 .29 .42 .44 .38 TOTAL 335.2 561.25 1305.0 15364.90 1062 1241.82 RIO JACAGUAS BASIN 50110900 RIO TOA VACA ABOVE LAGO TOA VACA, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) AUGUST 391 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CPS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL YEAR 15 15 15 18 20 19 18 19 19 17 17 17 16 16 15 15 13 14 13 12 13 12 11 12 12 11 9.2 8.9 8.0 7.8 17 444.9 5389.36 JULY 7 7 8 10 10 10 10 11 10 10 10 10 10 13 18 19 24 29 22 13 4 1 1 1 1 1 2 5 10 15 75 ... .30 .30 .34 .47 .53 .50 .49 .56 .52 .45 .44 .46 .44 .53 .70 .76 .86 1.1 .78 .41 .13 .03 .02 .03 .03 .02 .05 .13 .21 .31 7.0 18.90 44625.96 8.7 6.8 7.1 9.1 21 18 6.7 5.8 5.8 16 10 7.9 6.5 5.7 5.9 5.2 4.5 4.3 4.0 11 16 8.0 5.3 4.4 4.0 3.8 3.9 3.7 3.9 3.5 3.3 34 14 15 34 112 148 42 18 19 460 43 26 21 19 17 14 12 12 17 60 56 3 2 2 2 2 2 1 1 1 1 .85 .27 .28 1.2 16 9.6 .80 .26 .32 35 1.4 .56 .34 .29 .26 .19 .14 .14 .18 7.2 4.0 .09 .03 .02 .02 .02 .02 .02 .01 .00 .01 MEAN DISCHARGE (CPS) 3.2 3.0 3.0 3.0 3.0 3.4 4.5 31 15 4.9 3.4 2.8 2.7 2.4 2.3 2.5 2.9 2.6 2.4 3.8 4.2 3.0 3.4 4.6 3.6 3.7 3.2 3.1 6.3 62 MEAN CONCEN- TRATION (HQ/L) SEPTEMBER 3 6 8 10 10 10 13 195 62 13 9 5 1 1 1 1 1 1 1 1 1 4 11 13 11 10 8 9 20 996 SEDIMENT DISCHARGE (TONS/DAY) .03 .05 .07 .08 .08 .08 .20 58 3.6 .18 .08 .04 .01 .00 .00 .00 .00 .00 .00 .01 .01 .03 .12 .18 .12 .10 .07 .08 .41 705 229.8 79.52 198.9 768.63 392 RIO JACAGOAS BASIN 50110900 RIO TOA VACA ABOVE LAGO TOA VACA, PR--Continu«d WATER QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT DATE JAN 1992 05... 05.. . 05.. . MAR 31.. . APR 20.. . MAY 26... JUN 01.. . SEP 09.. . DATE JAN 1992 05.. . 05.. . 05... MAR 31.. . APR 20.. . MAY 26.. . JUN 01... SEP 09.. . TIME 1715 1750 1910 1555 1635 0345 1420 1535 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .016 MM 73 72 43 72 49 15 40 31 DIS- CHARGE, INST. CUBIC FEET PER SECOND 320 488 2950 24 247 3000 404 235 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM 84 76 53 78 59 19 50 39 SEDI- MENT, SUS- PENDED (MG/L) 6480 6230 13800 2720 6950 11100 5310 8330 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 96 95 65 98 71 26 68 51 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 5600 8200 110000 176 4630 89900 5800 5280 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 99 97 74 98.4 85 35 81 74 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM 43 41 22 42 23 8 25 11 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 99.9 99 84 99.2 94 52 92 88 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM 50 52 28 58 30 10 28 15 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 100 99.7 93 99.7 98 83 99 96 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 64 60 35 64 34 12 33 19 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 100 99.8 98 99.8 99 99 99.8 98 393 RIO JACAGUAS BASIN 50110900 RIO TOA VACA ABOVE LAGO TOA VACA, PR—Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1991 TO SBPTBMBER 1992 SILT AND CLAY PERCENT OF SOSPBNDBD SEDIMENT DATE OCT 1991 15... JAN 1992 05... 05... MAR 27.. . MAY 16... 23.. . 23.. . 24... 26.. . 26... 26... JON 01.. . SEP 30... 30... 30... TIME 1740 1655 1800 1530 1756 0945 1817 0127 0240 0915 1130 1505 1520 1635 1705 STREAM- PLOW, INSTAN- TANEOUS (CPS) SEDI- MENT, SUS- PENDED (MG/L) SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) SBD. SDSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 2.6 393 704 2.8 41 116 381 195 436 240 202 1560 274 432 239 75 7840 7300 436 200 805 1780 1100 2640 773 305 2100 8120 3880 5300 0.5 8320 13800 3.3 22 252 1830 577 3110 501 167 8860 6000 4520 3420 88 78 92 96 99 88 79 74 80 83 84 94 56 91 87 394 RIO JACAGOAS BASIN 50111500 RIO JACAOOAS AT JUANA DIAZ, PR LOCATION.—Lat 18°03'16", long 66°30'40", Hydrologic Unit 21010004, on Highway 14 bridge, 0.4 mi (0.6 km) west of Juana Diaz plaza, and 4.0 mi (6.4 km) downstream from Lago Ouayabal. DRAINAGE AREA.--49.8 mi* (129.0 km1 ). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—March 1984 to current year. GAGE.—Water-stage recorder. Elevation of gage is 131 ft (40 m), from topographic map. REMARKS.--Records poor. Flow regulation from Lago Guayabal. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB APR JUN JUL AUO SEP 1 e!2 e29 2 e!6 e!9 3 el? e8.2 4 el? eS.6 5 e27 eS.l 6 e30 e9.3 7 e34 e26 8 e69 e31 9 e65 e34 10 e72 e29 11 e74 e!3 12 e76 e9.7 13 e85 e7.8 14 e73 e48 15 e!9 e69 16 e9.3 e58 17 e9.9 e47 18 e3.4 e43 19 e2.0 e31 20 el. 5 e77 21 el. 3 e!08 22 e!6 el!2 23 e!7 e80 24 e9.0 e49 25 e3.4 e60 26 e2.4 el!6 27 e2.3 e88 28 e4.6 e65 29 e!4 e59 30 e22 eS9 31 e32 —— TOTAL 836.1 1395.7 MEAN 27.0 46.5 MAX 85 116 MIN 1.3 5.1 AC-FT 1660 2770 CFSM .54 .93 IN. .62 1.04 e Estimated e45 e41 e43 e44 e41 e38 e34 e31 e32 e34 e30 e26 e23 e24 e22 e23 e24 e23 e21 e20 e!7 ell e9.3 e2.7 e2.1 el. 7 e2.0 e2.5 e3.9 e3.5 el. 5 676.2 21.8 45 1.5 1340 .44 .51 STATISTICS OF MONTHLY MEAN DATA MEAN 157 115 MAX 445 287 (WY) 1986 1988 MIN 8.65 10.5 (WY) 1987 1987 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN- DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 43.3 151 1988 9.99 1989 e.86 e.54 e.24 el. 3 e93 e3170 eS7 e39 e42 e62 elOO elSO e!03 e75 e72 e72 e86 e68 e71 e57 e43 e!6 e!3 e!7 e!5 e9.7 eS.8 e5.4 e7.0 ell e!3 4475.84 144 3170 .24 8880 2.90 3.34 FOR WATER 32.1 144 1992 5.88 1987 elO ell e6.4 e6.4 5.9 6.3 28 42 26 24 25 29 37 29 27 17 14 11 5.7 6.0 5.6 4.9 5.8 .9 .1 .2 .3 .2 .0 ___ --- 408.7 14.1 42 4.0 811 .28 .31 YEARS 1984 9.11 16.9 1991 4.82 1990 3.8 3.6 3.7 3.8 3.4 3.0 2.1 1.3 1.7 2.1 2.8 3.3 3.1 3.2 3.1 3.3 3.4 3.5 3.1 3.1 4.1 4.6 3.3 3.2 3.2 3.1 3.1 3.1 3.2 3.3 3.3 97.9 3.16 4.6 1.3 194 .06 .07 - 1992 5.24 7.94 1988 3.16 1992 FOR 1991 CALENDAR YEAR 8327. 22. 454 1. 1. 16520 . 6. 61 9. 2. 6 8 Jul 16 3 Oct 21 9 May 1 46 22 4 8 4.3 5.1 3.8 4.0 4.3 4.7 5.1 4.8 5.4 31 25 24 11 6.5 7.4 31 70 21 17 190 191 84 55 41 34 28 38 38 30 28 --- 1042.4 34.7 191 3.8 2070 .70 .78 31 49 22 11 8.4 8.4 8.3 7.8 7.7 7.5 7.6 7.2 7.2 31 33 116 78 63 46 17 15 14 1010 542 293 2230 316 244 214 197 166 5808.1 187 2230 7.2 11520 3.76 4.34 282 222 162 136 120 107 88 134 143 110 105 151 121 91 70 57 47 36 29 24 46 47 28 27 25 27 27 27 20 19 2528 84.3 282 19 5010 1.69 1.89 16 14 14 31 47 58 56 60 55 50 52 47 40 39 36 36 32 26 23 24 25 29 14 8.7 7.0 6.6 6.7 6.7 7.0 6.8 11 884.5 28.5 60 6.6 1750 .57 .66 11 9.3 8.9 8.7 48 144 65 43 38 145 105 32 16 11 9.3 13 8.9 8.1 7.6 7.4 96 105 36 24 1? 12 12 11 8.9 11 7.4 1078.5 34.8 145 7.4 2140 .70 .81 7.7 7.6 6.4 6.0 5.9 7.6 8.5 21 40 13 8.9 6.9 8.0 6.5 5.8 5.6 5.6 5.4 6.4 12 50 35 33 39 31 32 26 26 61 35 562.8 18.8 61 5.4 1120 .38 .42 , BY WATER YEAR (WY) 9.20 34.7 1992 3.19 1991 FOR 1992 19794 54 3170 1 20500 22 39260 1 14 94 21 3 81.0 215 1985 2.68 1984 WATER YEAR .74 .1 Jan 6 . 24 Jan 3 .7 Dec 29 Jan 6 . 81 Jan 6 .09 .79 .3 45.4 198 1987 2.72 1984 24.6 82.4 1987 2.94 1990 WATER 50 80 13 4530 1 40000 29 36620 1 13 110 8 3 21.3 41.1 1985 2.25 1990 YEARS 1984 .6 .9 .0 Nov .24 Jan .3 Sep Oct .42 Oct .02 .79 .2 .4 40.0 164 1985 5.32 1986 - 1992 1986 1989 27 1987 3 1992 7 1990 7 1985 7 1985 > / '- '• - ' i / / ~-s r • ( I ' i \ \ > ^-^ V \ ) ' . w'-> L1" 01 23456 KILOMETERS ;___.]_. __ . i 01 234 MILES EXPLANATION A1125 SURFACE-WATER STATION AND NUMBER ^1162 QUALITY-OF-WATER STATION AND NUMBER • 132 WELL AND WELL NUMBER • 125780 LAKE-ELEVATION STATION Figure 24-South coast river basins the Rio Inabon to Rio Loco basins. to «D Ol 396 RIO INABON BASIN SO112500 RIO INABON AT REAL ABAJO, PR LOCATION.--Lat 18°05'10", long 66°33'46", Hydrologic Unit 21010004, at bridge on private road, off Highway 511 at Hacienda La Concord! a, 0.4 ml (0.6 km) upstream from diversion canal, 0.5 mi (0.8 km) north of Real Aba jo, and 6.1 mi (9.8 km) northeast of Plaza Degetau in Ponce. DRAINAGE AREA.--9.70 mi' (25.12 km'). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—1962-63 (annual low-flow measurements only), February to June 1964 (monthly July 1964 to July 1970, April 1971 to current year. inurements only), GAGE.—Hater-stage recorder. Elevation of gage is 410 ft (125 m), from topographic map. Prior to April 1971 nonrecording gage and crest-stage gage at different datum. REMARKS.—Records fair except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEE'f PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN PBB APR MAY JUN JUL AUG SEP 1 16 55 2 14 31 3 11 24 4 9.9 21 5 9.7 19 6 11 18 7 19 18 8 18 16 9 21 29 10 14 23 11 11 16 12 11 15 13 10 15 14 10 15 15 9.4 15 16 8.6 15 17 8.3 15 18 11 14 19 12 15 20 9.4 15 21 24 15 22 38 16 23 22 16 24 15 15 25 13 12 26 12 12 27 11 14 28 10 12 29 25 12 30 26 12 31 50 TOTAL 490.3 540 MEAN 15.8 18.0 MAX 50 55 MIN 8.3 12 AC-FT 973 1070 CFSM 1.63 1.86 IN. 1.88 2.07 e Estimated 11 9.9 11 13 11 9.5 8.8 9.0 8.7 8.2 8.1 7.3 7.1 7.2 7.2 7.4 7.4 6.7 6.6 9.8 11 5.9 5.9 5.6 5.4 5.2 5.1 4.5 4.0 3.8 5.9 237.2 7.65 13 3.8 470 .79 .91 STATISTICS OF MONTHLY MEAN DATA MEAN 48.5 35.5 MAX 148 77.9 (WY) 1986 1978 MIN 15.4 8.32 (WY) 1983 1977 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 12.9 26.5 1966 4.43 1977 FOR 8.4 12 10 13 173 686 89 44 33 27 30 34 24 21 19 18 16 14 13 12 12 11 11 11 11 11 9.8 9.6 9.6 9.1 8.6 1410.1 45.5 686 8.4 2800 4.69 5.41 8.3 7.7 7.2 7.5 7.1 e32 e22 e23 14 11 10 9.8 8.4 8.1 7.6 7.3 7.0 6.0 6.0 6.2 6.0 5.6 5.3 6.0 6.1 6.1 6.1 5.7 5.2 —— —— 268.3 9.25 32 5.2 532 .95 1.03 FOR WATER YEARS 1964 8.71 45.5 1992 4.11 1989 5.28 9.25 1992 3.05 1977 .9 .5 .5 .9 .8 .6 .5 .7 6.5 8.4 5.1 .5 .4 .3 .3 .2 .4 5.0 5.0 5.1 5.8 5.3 4.4 4.6 4.7 4.5 8.0 11 21 12 27 206.9 6.67 27 4.2 410 .69 .79 - 1992 5.72 16.4 1972 1.85 1977 1991 CALENDAR YEAR 4662.1 12.8 115 3.2 3.5 9250 1.32 17.88 24 9.9 4.8 Jul 16 Apr 26 Apr 24 25 42 21 9.3 7.3 6.2 5.3 4.3 8.7 9.3 6.1 6.5 6.5 7.3 11 16 19 16 29 89 67 34 25 21 17 15 14 13 12 12—— 574.8 19.2 89 4.3 1140 1.98 2.20 13 11 10 9.6 9.9 16 12 8.1 7.1 7.6 7.6 15 9.6 11 12 10 7.4 6.1 4.9 4.3 4.1 4.0 146 96 64 198 40 22 16 12 17 811.3 26.2 198 4.0 1610 2.70 3.11 9.8 9.9 9.8 9.1 7.5 6.5 7.3 13 22 8.5 12 23 17 11 8.3 6.6 5.7 5.1 6.6 8.6 14 9.3 8.3 13 15 13 12 9.5 12 12—— 325.4 10.8 23 5.1 645 1.12 1.25 11 10 9.9 8.5 8.0 8.2 8.1 8.7 8.4 7.6 7.3 7.7 7.2 6.9 7.1 6.9 6.9 11 10 7.2 6.5 5.6 5.5 5.6 6.0 5.6 5.3 5.1 4.6 4.5 19 239.9 7.74 19 4.5 476 .80 .92 16 12 11 16 41 22 11 11 15 52 33 20 15 12 11 10 9.6 9.8 8.7 8.1 36 18 11 8.5 8.5 8.4 10 7.9 9.7 10 11 483.2 15.6 52 7.9 958 1.61 1.85 10 9.9 9.6 9.9 9.6 12 62 42 23 20 17 13 11 11 26 17 14 11 10 17 14 12 21 17 21 21 16 31 25 53—— 586.0 19.5 62 9.6 1160 2.01 2.25 , BY WATER YEAR (WY) 8.00 19.2 1992 2.76 1975 FOR 1992 6173 16 686 3 4 5650 20 12240 1 23 25 11 5 19.5 76.7 1969 1.94 1967 WATER YEAR .4 .9 Jan 6 .8 Dec 30 .4 Mar 12 Jan 6 . 53 Jan 6 .74 .68 .2 16.5 49.8 1969 2.75 1967 12.4 32.7 1979 1.77 1990 WATER 18 30 9 2500 1 19000 25 13460 1 26 41 9 3 17.6 46.1 1979 4.47 1974 YEARS 1964 .6 .9 .57 Sep .80 Jul .1 Mar Oct .30 Oct .92 .02 .1 .1 33.7 119 1975 7.70 1986 - 1992 1969 1974 16 1975 23 1977 31 1977 7 1985 7 1985 RIO BUCANA BASIN 50113800 RIO CBRRILLOS ABOVE LACK) CBRRILLOS NEAR PONCE, PR 397 LOCATION.--1*t 18°07'01", long 66°36'17", Hydrologic Unit 21010004, on right bank, 0.3 mi (0.5 km) downstream from confluence with Rio San Patricio, 0.1 mi (0.2 km) southwest of Hwy 139 and 2.4 mi (3.7 km) northwest of Maragues. DRAINAGE AREA.-- 15.4 mi 1 (39.9 km1 ). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--December 1988 to current year. GAGE.--Water-stage recorder and crest-stage gage. Elevation of gage is 720 ft (210 m), from topographic map. REMARKS.--Records fair except those for estimated daily discharges, which are poor, satellite telemetry at station. Gage-height and precipitation DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB APR MAY JUN JUL AUG SEP 1 32 34 2 26 18 3 23 13 4 21 12 5 19 11 6 19 13 7 30 13 8 22 13 9 38 26 10 20 19 11 17 15 12 15 13 13 14 13 14 17 14 15 15 14 16 13 14 17 12 15 18 42 15 19 18 15 20 14 15 21 16 15 22 33 15 23 18 15 24 14 15 25 13 15 26 12 17 27 12 18 28 11 19 29 48 19 30 83 18 31 77 —— TOTAL 764 481 MEAN 24.6 16.0 MAX 83 34 KIN 11 11 AC-FT 1520 954 CFSM 2.07 1.35 IN. 2.39 1.50 e Estimated 18 18 e25 e29 e26 e25 e24 e25 e22 21 20 19 18 18 16 16 16 15 15 17 20 14 13 12 12 11 11 10 9.6 8.8 8.5 532.9 17.2 29 8.5 1060 1.44 1.67 STATISTICS OF MONTHLY MEAN DATA MEAN 89.9 34.8 MAX 154 50.2 (WY) 1991 1991 MIN 24.6 16.0 (WY) 1992 1992 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK PLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS. 90 PERCENT EXCEEDS 16.4 18.2 1991 13.3 1989 FOR 9.0 10 7.8 7.1 331 717 136 64 50 41 43 49 33 27 26 24 23 20 20 19 18 18 16 16 16 17 16 14 14 14 14 1829.9 59.0 717 7.1 3630 4.96 5.72 FOR WATER 22.0 59.0 1992 7.46 1989 14 13 13 12 12 34 24 23 16 15 16 15 13 12 12 11 11 11 10 10 10 9.7 9.7 9.3 9.3 9.5 9.9 9.8 9.3 ___ —— 383.5 13.2 34 9.3 761 1.11 1.20 YEARS 1989 8.83 13.2 1992 6.34 1990 9.2 8.8 8.8 8.5 9.1 8.5 8.4 9.1 34 20 11 9.3 9.4 9.3 9.4 9.3 9.4 10 9.3 9.7 9.7 10 9.7 10 10 12 15 15 15 12 16 354.9 11.4 34 8.4 704 .96 1.11 - 1992 13.0 27.5 1989 4.77 1990 1991 CALENDAR YEAR 7118. 19. 163 4. 4. 14120 1. 22. 36 14 5. 4 5 Aug 22 8 Mar 13 8 Mar 13 64 25 7 28 69 29 15 14 12 11 10 11 12 14 14 11 12 26 21 28 19 52 65 49 27 20 17 15 14 13 13 13 13 --- 667 22.2 69 10 1320 1.87 2.09 13 13 12 11 11 15 13 11 12 12 12 17 17 17 21 23 19 18 19 18 13 12 281 207 206 205 108 68 55 48 54 1561 50.4 281 11 3100 4.23 4.88 51 44 40 36 32 29 27 34 33 29 38 62 54 46 40 35 34 32 30 27 37 25 23 21 21 21 20 19 18 18 976 32.5 62 18 1940 2.73 3.05 17 16 16 15 14 14 14 14 13 12 12 12 12 12 12 12 12 49 22 19 17 16 15 15 15 14 15 15 15 15 43 514 16.6 49 12 1020 1.39 1.61 19 16 15 39 75 56 24 21 37 102 64 52 41 38 30 23 20 18 16 15 64 27 18 16 15 18 18 16 19 17 16 965 31.1 102 15 1910 2.62 3.02 16 15 14 14 14 51 168 81 43 96 68 40 34 29 57 44 34 34 34 33 32 32 51 38 33 31 26 46 37 30 1275 42.5 168 14 2530 3.57 3.99 , BY WATER YEAR (WY) 15.4 24.3 1989 6.38 1990 FOR 1992 10304 28 717 7 8 8140 9 7 20440 2 32 49 16 10 20.9 50.4 1992 4.58 1990 WATER YEAR .2 .2 Jan 6 . 1 Jan 4 .7 Dec 29 Jan 5 . 65 Jan 5 . 0 Jan 4 .37 .21 22.6 36.5 1989 6.37 1990 15.0 26.7 1991 4.66 1990 WATER 28 33 22 717 3 3 8140 9 3 20410 2 32 64 14 4 31.0 53.1 1991 11.4 1990 YEARS 1989 - .2 .4 .9 Jan 6 .3 Aug 16 .5 Aug 14 Jan 5 . 65 Jan 5 .3 Aug 16 .37 .16 .9 58.5 88.0 1989 30.4 1991 1992 1991 1990 1992 1990 1990 1992 1992 1990 398 RIO BOCANA BASIN 50114000 RIO CERRILLOS NEAR PONCE, PR LOCATION.--Lat 18°04'15", long 66°34'51", Hydrologic Unit 21010004, on right bank off Highway 139, 0.8 mi (1.3 km) below Lago Cerrillos Dam, 2.3 mi (3.7 km) upstream from Quebrada Ausubo and 4.6 mi (7.4 km) northeast of Plaza Degetau in Ponce. DRAINAGE AREA. --17.8 mi2 (46.1 km1 ), excludes 17.4 mi2 (45.1 km2 ), upstream from Lago Cerrillos Dam. WATER-DISCHARGE RECORDS PERIOD OF RECORD.--February to April 1964 (monthly measurements only). Nay 1964 to June 1985, July 1985 to April 1991 (semi-monthly measurements only). Hay 1991 to current year. GAGE.--Water-stage recorder. Datum of gage is 253.10 ft (77.145 m), above mean sea level. Prior to Narch 22, 1977 at site 0.15 mi (0.24 km) upstream and datum 9.90 ft (3.018 m) higher. REMARKS.--Records poor. Flow regulated by Lago Cerrillos Dam since Nay 1991. Gage-height and precipitation satellite telemetry at station. Prior to June 1985 some low-flow regulation by construction upstream. Maximum discharge prior to regulation, 22,400 ft3/s (6.34 mVs), Sept. 16, 1975, gage-height, 11.2 ft (3.414 m), site and datum them in use from floodmarks, from rating curve extended above 150 ft'/s (4.25 m3/«), on basis of slope-area measurements of peak flow; minimum discharge prior to regulation, 2.2 ft3 /" (0.062 mVe), Nay 28, 1967. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JtJL AUG SEP 1 e41 e35 2 e33 e21 3 e29 e!6 4 e26 e!5 5 e24 e!3 6 e24 e!6 7 e39 e!7 8 e28 e!7 9 e45 e33 10 e25 e25 11 e22 e!9 12 e!9 e!5 13 18 e!4 14 22 e!4 15 19 e!2 16 16 e!3 17 .15 e!2 18 e48 e!2 19 «22 ell 20 a!8 e!2 21 e20 e!2 22 e42 ell 2' e23 e!2 e!8 ell ^, e!7 elO 26 e!5 e9.8 27 e!5 e!2 28 e!4 e!3 29 e60 el3 30 e!02 e!2 31 e97 —— TOTAL 956 457.8 MEAN 30.8 15.3 MAX 102 35 MIN 14 9.8 AC-FT 1900 908 CFSM 1.73 .86 IN. 2.00 .96 e Estimated e!2 e!2 e!6 e!9 e!7 e!5 e!3 e!5 e!3 ell elO e9.6 e9.4 e9.4 e9.0 e9.0 e9.0 e8.6 e8.6 e9.6 e!5 el3 e!2 ell ell elO elO c9.4 e9.0 e8.6 eS.O 352.2 11.4 19 8.0 699 .64 .74 STATISTICS OF MONTHLY MEAN DATA MEAN 30.8 15.3 MAX 30.8 15.3 (WY) 1992 1992 MIN 30.8 15.3 (WY) 1992 1992 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 11.4 11.4 1992 11.4 1992 e8.4 elO e9.2 e8.6 e450 e900 e!50 e78 e60 e52 e54 e62 e40 e35 e33 e31 e29 e25 e25 e24 e23 e23 020 e20 o20 e22 e21 e!8 el8 e!6 15 2300.2 74.2 900 8.4 4560 4.17 4.81 FOR WATER 74.2 74.2 1992 74.2 1992 15 14 14 14 13 34 32 30 19 16 16 19 15 14 14 13 12 12 11 11 11 10 10 10 9.5 10 9.9 9.9 8.8 ___ --- 8.1 7.8 7.8 8.1 8.5 7.5 7.5 7.8 23 38 12 10 9.9 9.6 9.8 9.7 9.3 10 9.2 7.6 11 10 8.8 9.6 9.9 10 11 15 9.9 7.6 5.2 427.1 329.2 14.7 34 8.8 847 .83 .89 YEARS 1991 - 14.7 14.7 1992 14.7 1992 FOR 1992 10454. 28. 900 . 1. 1100 6. 20740 1. 21. 55 15 6. 10.6 38 5.2 653 .60 .69 1992 10.6 10.6 1992 10.6 1992 26 19 84 16 11 9.3 8.1 7.2 6.9 11 8.1 15 8.5 9.2 26 33 32 23 55 102 81 37 22 17 15 12 12 11 9.9 9.9 737.1 24.6 102 6.9 1460 1.38 1.54 , BY WATER 24.6 24.6 1992 24.6 1992 9.9 10 8.8 7.8 7.5 10 13 7.9 7.5 6.5 6.2 6.6 18 16 24 25 17 18 13 17 11 10 366 262 185 317 122 76 55 49 53 1755.7 56.6 366 6.2 3480 3.18 3.67 YEAR (WY) 35.6 56.6 1992 14.5 1991 51 46 42 38 32 31 29 33 62 35 39 74 62 47 44 32 29 28 26 24 35 25 22 21 19 18 18 17 16 16 --- 1011 33.7 74 16 2010 1.89 2.11 24.1 33.7 1992 14.5 1991 WATER YEAR 14 6 64 7 07 60 85 8 Jan 6 Aug 19 Aug 24 Jan 6 Jan 6 17 16 16 16 17 15 14 12 15 14 14 16 12 9.6 12 12 11 51 28 22 16 14 12 11 11 11 13 11 9.5 8.9 39 496.0 16.0 51 8.9 984 .90 1.04 20.3 24.6 1991 16.0 1992 WATER 28 28 28 900 1 1100 6 20690 1 21 45 14 7 20 12 11 22 80 71 24 18 32 103 65 46 42 32 29 24 20 11 .64 1.1 4.2 3.0 2.3 1.7 1.6 1.6 1.6 1.7 2.0 1.9 2.2 687.54 22.2 103 .64 1360 1.25 1.44 22.6 23.1 1991 22.2 1992 YEARS 1991 .6 .6 .6 Jan . 64 Aug .7 Aug Jan . 07 Jan .60 .80 .8 20 1.8 1.9 1.9 1.7 2.0 2.0 57 118 79 83 123 114 78 83 90 60 2.1 2.2 2.6 2.1 1.9 2.0 2.1 2.2 2.3 2.1 2.0 2.0 2.4 --- 944.3 31.5 123 1.7 1870 1.77 1.97 23.5 31.5 1992 15.4 1991 - 1992 1992 1992 6 1992 19 1992 24 1992 6 1992 6 1992 RIO BUCANA BASIN 50114000 RIO CERRILLOS NEAR PONCE. PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--Water yeara 1964 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 399 DATE OCT 1991 09... DEC 18... FEB 1992 18... MAY 07... JUN 23... AUO 27... DATE OCT 1991 09... DEC IB. . . FEB 1992 18... MAY 07... JUN 23... AUO 27... DATE OCT 1991 09... DEC 18... FEB 1992 18... MAY 07.. . JUN 23... AUO 27.. . TIME 1515 1200 1055 1100 1130 1030 CALCIUM DIS- SOLVED (MO/L AS CA) 39 -- -- 40 -- 110 SOLIDS, DIS- SOLVED (TONS PER DAY) 1B.O -- -- 7.61 -- 2.03 DIS- CHARGE , INST. CUBIC FEET PER SECOND 33 8.4 12 14 24 1.6 MAGNE- SIUM. DIS- SOLVED (MG/L AS MO) 6.6 -- -- 6.5 -- 13 RESIDUE TOTAL AT 105 DEO. C. SUS- PENDED (MG/L) 13 1 5 <1 14 14 SPE- CIFIC CON- DUCT- ANCE (US/CM) 360 309 343 300 315 784 SODIUM, DIS- SOLVED (MG/L AS NA) 9.9 -- — 12 -- 32 NITRO- OEN, NITRATE TOTAL (MG/L AS N) -- -- -- 0.400 -- 11.0 PH WATER WHOLE FIELD (STAND- ARD UNITS) 8.2 8.2 8.0 7.9 7.0 7.9 SODIUM AD- SORP- TION RATIO 0.4 -- -- 0.5 -- O.B NITRO- OEN, NITRITE TOTAL (MG/L AS N) <0.010 <0.010 <0.010 0.010 <0.010 0.040 TEMPER- ATURE WATER (DEO C) 25.5 23.5 26.0 24.5 27.5 26.0 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 1.1 — -- 1.2 -_ 1.5 NITRO- GEN, N02+N03 TOTAL (MO/L AS N) 0.440 0.290 0.670 0.410 0.500 11.0 TUR- BID- ITY (NTU) 15 1.3 1.6 2.1 1.9 8.0 ALKA- LINITY WAT WH TOT FET FIELD MO/L AS CAC03 140 130 140 150 130 180 NITRO- OEN, AMMONIA TOTAL (MG/L AS N) 0.020 <0.010 0.030 <0.010 0.040 0.060 OXYOEN, DIS- SOLVED (MO/L) 7.8 9.0 9.4 8.6 9.0 6.4 SULFIDE TOTAL (MG/L AS S) <0.5 -- -- <0.5 __ -- NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) <0.20 <0.20 <0.20 <0.20 <0.20 <0.20 OXYOEN, OXYOEN DIS- DEMAND, SOLVED CHEM- (PER- ICAL CENT (HIOH SATUR- LEVEL) ATION) (MO/L) 95 <10 107 <10 112 <10 103 <10 109 <10 7B <10 CHLO- SULFATE RIDE. DIS- DIS- SOLVED SOLVED (MO/L (MG/L AS S04) AS CL) 22 13 __ __ 22 7.8 __ 160 16 PHOS- PHORUS ARSENIC TOTAL TOTAL (MO/L (UO/L AS P) AS AS) 0.040 1 0.020 0.030 0.020 <1 0.040 <0.010 COLI- FORM, FECAL, 0.45 UM-MF (COLS . / 100 ML) K930 20 10 K150 K10 370 FLUO- RIDE. DIS- SOLVED (MO/L AS F) <0.10 -- -- 0.10 -- 0.20 BARIUM, TOTAL RECOV- ERABLE (UO/L AS BA) <100 -- -- <100 -- -- STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 550 70 20 K160 40 210 SILICA, DIS- SOLVED (MO/L AS SI02) 24 -- — 19 -- 25 BORON, TOTAL RECOV- ERABLE (UO/L AS B) 30 — -- 30 — -- HARD- NESS TOTAL (MO/L AS CAC03) 120 .- -- 130 -- 330 SOLIDS, SUM OF CONSTI- TUENTS. DIS- SOLVED (MO/L) 200 -- -- 199 -- 471 CADMIUM TOTAL RECOV- ERABLE (UO/L AS CD) 3 -- -- <1 -- -- K - non- ideal count 400 RIO BOCANA BASIN 50114000 RIO CERRILLOS NEAR PONCE, PR--Continu*d WATER-QUALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 CHRO- MIUM, TOTAL RECOV- ERABLE (UO/L AS CR) COPPER, TOTAL RECOV- ERABLE (00/L AS CO) IRON, TOTAL RECOV- ERABLE (00/L AS FE) LEAD, TOTAL RECOV- ERABLE (00/L AS PB) MANGA- NESE, TOTAL RECOV- ERABLE (00/L AS MN) MERCORT TOTAL RECOV- ERABLE (00/L AS HO) SELE- NIUM, TOTAL (00/L AS SE) SILVER, TOTAL RECOV- ERABLE (00/L AS AO) ZINC. TOTAL RECOV- ERABLE (OO/L AS ZN) CYANIDE TOTAL (MO/L AS CN) PHENOLS TOTAL (00/L) METHY- LENE BLOB ACTIVE SOB- STANCE (MO/L) OCT 1991 09... DEC IB... FEB 1992 IB... MAY 07... JON 23... AOO 27... <1 1300 260 <1 BO BO <0.10 <1 <1 <1 <1 <0.010 <0.010 0.02 0.02 RIO BUCANA BASIN 50114390 RIO BOCANA AT HWY 14 BRIDGE NEAR PONCE, PR 401 LOCATION.--Lat 18°02'29", long 66°34'58", Hydrologic Unit 21010004, on left bank, 200 ft (61 m) upstream fro* bridge on Highway 14 and 4.0 mi (6.4 km) downstream from Lago Cerrillos Dam, 2.8 mi (4.5 km) northeast of Degetau Plaza in Ponce. DRAINAGE AREA.--24.9 mi' (64.5 km 1 ). HATER-DISCHARGE RECORDS PERIOD OF RECORD.—October 1985 to September 1986 (maximum only), published as "Rio Bucani Floodway Channel at Highway 14 bridge", October 1986 to July 1987 (maximum only), August 1987 to current year. GAGE.--Hater-stage recorder and crest-stage gage. Datum of gage is 116.40 ft (35.500 m) above mean sea level. Prior to Oct. 1, 1986, crest-stage gage located at Highway 14 bridge, at elevation of mean sea level. REMARKS.--Records poor. Only minor regulation of low flow until Aug. 18, afterward flow regulated by Lago Cerrillos Dam 0.4 mi upstream. Gage-height and precipitation satellite telemetry at station. DAY DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUQ SEP 1 18 250 2 30 34 3 18 20 4 14 17 5 14 21 6 13 16 7 18 20 8 38 18 9 50 21 10 52 49 11 28 17 12 28 13 13 23 12 14 23 11 15 28 12 16 20 11 17 17 14 18 28 12 19 86 11 20 18 11 21 25 11 22 44 11 23 89 10 24 19 11 25 16 10 26 14 10 27 13 28 28 12 34 29 13 29 30 218 10 31 319 - — TOTAL 1346 754 MEAN 43.4 25.1 MAX 319 250 MIN 12 10 AC-FT 2670 1500 CFSM 1.74 1.01 IN. 2.01 1.13 e Estimated STATISTICS OF MONTHLY MEAN MEAN 216 98.9 MAX 527 222 (WY) 1991 1988 MIN 43.4 25.1 (WY) 1992 1992 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 9.1 9.9 11 13 12 11 12 12 15 15 15 15 15 15 14 14 14 14 13 15 22 16 15 15 15 15 14 14 14 14 14 432.0 13.9 22 9.1 857 .56 .65 DATA 23.4 49.1 1988 13.9 1992 FOR 14 18 16 15 107 4340 2840 725 349 233 185 438 205 132 102 88 82 67 57 57 55 50 47 42 39 37 32 26 23 17 16 10454 337 4340 14 20740 13.5 15.62 14 14 13 13 13 29 97 51 25 17 16 23 15 13 14 13 12 10 9.7 8.9 8.9 9.0 9.6 9.7 11 8.8 8.6 8.6 8.0 --- 502.8 17.3 97 8.0 997 .70 .75 FOR HATER YEARS 1987 78.9 337 1992 9.84 1989 11.4 17.3 1992 7.39 1989 7.3 7.0 6.9 7.0 8.1 7.5 7.3 7.5 11 127 14 11 11 10 e9.6 e9.6 e9.4 e8.6 e8.8 e9.0 e8.8 e8.8 e8.6 e8.0 e8.6 e8.4 e8.2 e8.0 e!6 e24 e21 426.0 13.7 127 6.9 845 .55 .64 - 1992 18.0 48.0 1989 5.81 1990 1991 CALENDAR YEAR 10831 29 531 4 5 21480 1 16 54 13 6 .7 .7 Aug 22 .8 Apr 17 .4 Mar 9 .19 .18 .8 e9.6 ell 86 17 e!5 e!2 ell elO e9.0 e!2 e!3 e8.8 e9.8 15 51 78 62 55 « 184*' 194 113 81 35 30 31 22 23 18 17--- 1275.2 42.5 194 8.8 2530 1.71 1.91 16 15 13 11 9.4 14 27 10 7.3 8.0 7.2 7.7 21 e!7 e!4 elO elO e20 e30 e!3 e!2 e9.6 e9.4 e580 e290 e!350 e!75 ellS e55 e32 e32 2940.6 94.9 1350 7.2 5830 3.81 4.39 e30 e28 e23 e29 e22 e20 e!7 e!9 e21 e37 e24 e44 e64 e48 e32 e30 e28 e26 e24 e24 e24 e44 e28 e25 e23 e22 e21 e!9 e!9 e!9 --- 834 27.8 64 17 1650 1.12 1.25 e!8 e!7 e!7 e!7 e!7 e!7 e!8 e!7 e!7 e!6 e!4 e!7 e!8 e!5 ell ell ell elO e90 e69 e48 e28 e!5 e!4 e!3 e!3 e!3 e!2 e!2 ell e!2 628 20.3 90 10 1250 .81 .94 21 15 14 19 39 41 21 17 23 43 38 28 28 21 22 19 17 14 8.5 7.6 14 6.8 5.7 6.4 6.0 5.5 4.8 4.3 3.7 3.3 2.8 519.4 16.8 43 2.8 1030 .67 .78 3.4 5.3 3.9 3.4 2.8 2.8 9.0 11 50 43 37 53 50 41 39 38 40 13 3.0 3.9 3.3 4.0 3.0 2.8 3.2 3.0 2.8 2.5 2.6 4.6 484.3 16.1 53 2.5 961 .65 .72 , BY HATER YEAR (WY) 21.4 42.5 1992 9.58 1991 FOR 1992 20596. 56. 4340 2. 2. 9890 12. 40850 2. 30. 58 15 7. 30.0 94.9 1992 5.89 1990 HATER YEAR 3 3 Jan 6 5 Sep 28 8 Sep 23 Jan 6 45 Jan 6 26 77 5 36.3 80.5 1989 8.09 1990 25.1 51.4 1991 6.08 1990 HATER 62 78 52 4340 2 2 17400 13 45040 2 33 122 15 6 62.4 169 1988 16.8 1992 YEARS 1987 .2 .0 .1 Jan .5 Sep .8 Sep Oct .48 Oct .50 .92 .5 98.3 265 1989 16.1 1992 - 1992 1991 1990 6 1992 28 1992 23 1992 7 1985 7 1985 402 RIO PORTOOOBS BASIN 50115000 RIO PORTOGDBS NEAR PONCB, PR LOCATION.--Lat 18°04'45", long 66°38'01*, Hydrologic Unit 21010004, on right bank 30 ft (9 m) upstream from bridge on Highway 504, 0.2 mi (0.3 km) upstream from small unnamed tributary, 4.4 mi (7.1 km) upstream from Rio Chiquito, and 4.7 mi (7.6 km) north of Plaza Degetau in Ponce. DRAINAGE AREA.--8.82 mi' (22.84 km1 ). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--February to June 1964 (monthly measurements only), July 1964 to current year. GAGE.—Water-stage recorder. Elevation of gage is 470 ft (143 m), from topographic map. Prior to Dec. 4, 1964, non-recording gage at same site and datum. REMARKS.--Records fair except those for estimated daily discharges, which are poor. Some low-flow regulation due to unknown activity upstream. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JDL AUG SEP 1 10 12 2 8.0 8.0 3 6.8 6.6 4 5.3 5.9 5 5.1 e5.3 6 4.8 e5 . 0 7 7.0 e4 . 8 8 6.3 e!4 9 5.1 14 10 7.6 15 11 6.1 7.6 12 e4.9 e6.4 13 e4.9 e5.2 14 e6.0 e4.5 15 e4.3 e3.8 16 e3.8 e3.5 17 e6.7 e4.4 18 e!8 e3.9 19 e4.0 e3.5 20 e9.7 3.5 21 e!9 3.4 22 e!4 3.3 23 e5.9 3.2 24 eS.O 3.1 25 e4.4 3.0 26 e4.2 3.9 27 e4.0 5.4 28 e3.8 5.6 29 e50 4.1 30 e70 3.5 31 e54 TOTAL 368.7 175.4 MEAN 11.9 5.85 MAX 70 15 MIN 3.8 3.0 AC-FT 731 348 CFSM 1.35 .66 IN. 1.56 .74 e Estimated STATISTICS OF MONTHLY MEAN MEAN 43.4 33.5 MAX 116 80.1 (WY) 1991 1988 MIN 11.9 5.85 (WY) 1992 1992 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN- DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC- FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 3.3 3.2 3.4 3.9 3.1 3.0 3.0 2.8 2.8 2.9 2.9 2.8 2.6 2.6 2.5 2.6 2.7 2.6 2.5 2.6 3.3 2.4 2.4 2.4 2.5 2.3 2.2 2.2 2.1 2.2 2.2 84.0 2.71 3.9 2.1 167 .31 .35 DATA 12.5 27.3 1988 2.71 1992 FOR 14 6.8 2.6 2.0 212 794 67 19 9.8 7.0 e8.7 e31 e58 e39 e!9 e!4 e!3 e!2 elO e9.1 e7.8 e7.8 e7.3 e6.8 e6.3 e5.8 e5.3 e4.8 e4.3 e3.8 e3.6 1411.6 45.5 794 2.0 2800 5.16 5.95 FOR WATER 8.81 45.5 1992 3.65 1989 e3.6 e3.3 e3.3 e3.3 5.6 25 25 29 10 8.1 8.2 7.7 7.2 6.7 6.1 6.0 6.0 5.7 5.8 5.4 5.0 4.6 4.3 3.9 3.7 3.6 3.7 3.8 3.6 217.2 7.49 29 3.3 431 .85 .92 YEARS 1964 6.13 13.3 1976 2.62 1989 3.2 3.3 3.4 3.6 3.6 3.4 3.4 3.3 25 24 6.0 4.8 4.4 .4 .3 .1 .2 .3 .2 .2 .2 .0 3.7 4.0 3.9 3.8 7.1 11 8.9 4.4 8.8 184.9 5.96 25 3.2 367 .68 .78 - 1992 5.74 13.4 1976 2.08 1977 1991 CALENDAR YEAR 2959. 8. 75 2. 2. 5870 . 12. 15 5. 3. 6 11 Aug 22 1 Dec 29 2 Dec 25 92 48 2 0 36 46 26 8.3 5.8 5.0 4.5 4.1 5.8 e6.4 4.1 4.9 4.0 3.7 6.3 7.6 5.9 4.7 5.2 11 19 11 5.9 4.3 3.8 3.5 e3.3 e3.2 e3.2 e3.2 —— 265.7 8.86 46 3.2 527 1.00 1.12 e3.2 e3.1 e3.0 e2.8 e3.1 e4.1 4.9 3.2 3.0 2.9 2.8 3.0 7.6 8.2 eS.O eS.O e9.5 14 6.4 5.3 4.3 4.3 252 123 87 104 36 16 11 9.1 13 759.8 24.5 252 2.8 1510 2.78 3.20 13 10 13 9.8 8.6 7.9 8.6 9.7 17 11 13 29 21 15 14 13 12 11 11 11 20 12 11 10 10 10 10 9.8 10 9.0 370.4 12.3 29 7.9 735 1.40 1.56 7.8 7.7 7.8 7.8 8.0 8.2 7.9 7.7 7.0 6.4 7.7 8.4 6.4 4.7 4.8 4.5 4.5 43 21 14 7.6 6.6 5.8 5.5 5.7 5.6 5.4 5.4 5.3 5.4 9.8 263.4 8.50 43 4.5 522 .96 1.11 8.2 5.5 5.3 13 37 28 9.1 7.3 17 31 22 35 29 19 14 10 8.8 8.0 7.3 6.8 45 21 11 8.9 8.0 7.5 6.8 6.6 7.8 7.9 6.4 458.2 14.8 45 5.3 909 1.68 1.93 6.6 6.5 5.9 5.6 5.5 33 59 48 27 65 42 17 22 12 8.6 9.5 8.0 6.4 8.1 19 12 47 29 15 25 24 11 17 18 ». 6 —— 621.3 20.7 65 5.5 1230 2.35 2.62 , BY WATER YEAR (WY) 7.08 27.1 1983 2.45 1974 FOR 1992 5180. 14. 794 2. 2. 6790 14. 2. 10280 1. 21. 25 6. 3. 19.3 72.9 1985 1.65 1973 WATER YEAR 6 2 Jan 6 0 Jan 4 2 Dec 25 Jan 6 01 Jan 6 0 Dec 31 60 85 4 1 14.9 48.3 1979 2.33 1974 14.6 54.2 1979 2.65 1976 WATER 18. 38. 8. 2440 1. 1. 21000 20. 1. 13390 2. 28. 40 8. 3. 20.7 87.5 1979 4.20 1972 YEARS 1964 5 0 04 Sep 1 May 3 May Oct 20 Oct 0 May 10 48 2 1 35.3 132 1975 7.22 1991 - 1992 1979 1974 16 1975 29 1973 23 1973 7 1985 7 1985 29 1973 RIO PORTUGUBS BASIN 50115000 RIO PORTUGUES NEAR PONCE, PR—Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1964 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 403 DATE OCT 1991 03. .. DEC 31. .. FBB 1992 20. .. MAY 06... JUL 01. .. SEP 01. .. TIME 1135 0940 0935 0915 1035 1020 DIS- CHARGE, INST. CUBIC FEET PER SECOND 2.6 2.5 5.3 3.7 4.8 6.9 SPE- CIFIC CON- DUCT- ANCE (US /CM) 277 310 310 309 307 290 PH WATER WHOLE FIELD (STAND- ARD UNITS) 8.7 8.1 7.4 7.7 8.0 8.5 TEMPER- ATURE WATER (DBG C) 25.5 20.5 21.5 23.5 25.5 24.7 TUR- BID- ITY (NTU) 1.8 0.60 0.60 0.60 14 0.60 OXYGEN, DIS- SOLVED (MG/L) 8.5 8.6 9.0 7.9 8.6 7.8 OXYGEN, OXYGEN DIS- DEMAND, SOLVED CHEM- (PBR- ICAL CENT (HIGH SATUR- LEVEL) ATION) (MG/L) 105 <10 92 <10 114 14 93 <10 96 <10 80 <10 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 310 K130 K40 K10 K66 60 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 290 260 K240 770 K100 K110 DATE OCT 1991 03.. . DEC 31.. . FBB 1992 20.. . MAY 06... JUL 01.. . SEP 01.. . HARD- NESS TOTAL (MG/L AS CACO3 ) 120 -- -- 140 -- 130 CALCIUM DIS- SOLVED (MG/L AS CA) 39 — -- 43 -- 40 MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) 6.6 -- -- 7.5 -- 6.5 SODIUM, DIS- SOLVED (MG/L AS NA) 9.8 — — 14 -- 9.6 SODIUM AD- SORP- TION RATIO 0.4 -- -- 0.5 -- 0.4 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 1.1 — — 1.8 — 1.3 ALKA- LINITY WAT WH TOT FET FIELD MG/L AS CAC03 130 150 140 130 140 120 SULFIDB TOTAL (MG/L AS S) <0.5 — — 0.8 — — SULFATB DIS- SOLVED (MG/L AS SO4) 8.8 -- -- 8.5 -- 7.4 CHLO- RIDE, DIS- SOLVED (MG/L AS CL) 9.2 — — 10 — 9.0 DATE OCT 1991 03.. . DEC 31. . . FEB 1992 20. .. MAY 06. . . JUL 01.. . SEP 01.. . FLUO- RIDB, DIS- SOLVED (MG/L AS F) •cO.10 -- -- <0.10 -- 0.10 SILICA, DIS- SOLVED (MG/L AS SI 02) 22 -- -- 18 -- 18 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 174 -- -- 181 -- 173 SOLIDS, DIS- SOLVED (TONS PER DAY) 1.22 -- — 1.80 -- 3.22 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 4 1 2 <1 7 1 NITRO- GEN, NITRATE TOTAL (MG/L AS N) — -- -- 0.440 0.990 — NITRO- GEN, NITRITE TOTAL (MG/L AS N) •cO.010 <0.010 <0.010 0.010 0.010 <0.010 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 0.580 0.610 0.310 0.450 1.00 0.680 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.010 0.010 0.030 <0.010 0.020 0.030 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) -- -- 0.17 -- 0.18 -- K = non-ideal count 404 RIO PORTUGUES BASIN 50115000 RIO PORTOQUBS NEAR PONCB, PR—Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 03... DEC 31.. . FEE 1992 20... MAY 06... JUL 01... SEP 01... DATE OCT 1991 03... DEC 31.. . FBB 1992 20... MAY 06... JUL 01... SEP 01.. . NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) <0.20 <0.20 0.20 <0.20 0.20 <0.20 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) — — 0.51 -- 1.2 -- LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N03) -- -- 2.3 -- 5.3 -- MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.020 0.040 0.040 0.030 0.030 0.020 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) ARSENIC TOTAL (UG/L AS AS) <1 -- -- <1 -- -- SELE- NIUM, TOTAL (UG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 — — 100 — — SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) -- -- -- 20 -- -- ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 — — <1 — -- CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) 1 -- -- <1 -- -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) <10 — — <10 — -- MBTHY- LBNB BLUB ACTIVE SUB- STANCE (MG/L) 160 30 <0.10 <0.10 <0.010 <0.010 0.02 0.01 RIO PORTUGUBS BASIN 50116200 RIO PORTUGUBS AT PONCE, PR WATER-QUALITY RECORDS LOCATION. --Lat 18°00'20", long 66°36'28«, 1,300 ft (400 •) south of Las America* Avenue Bridge, 1.2 mi (1.9 km) south of CSC 50115900, 0.8 mi (1.3 km) west of Highways 1 and 2 junction, and 0.7 mi (1.1 km) southeast of Ponce. DRAINAGE AREA.--18.9 mi> (49.0 km*). PERIOD OF RECORD.--Water years 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 405 DATE NOV 1991 04... JAN 1992 02... FEB 19... MAY 06... JUL 01... SEP 01... TIME 1035 1055 1110 1120 1145 1140 DIS- CHARGE, INST. CUBIC FEET PER SECOND 3.2 7.3 2.6 4.8 7.5 3.4 SPE- CIFIC CON- DUCT- ANCE (US/CM) 470 410 515 672 485 485 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.5 7.4 7.8 7.1 7.7 8.0 TEMPER- ATURE WATER (DBG C) 24.5 23.0 24.5 27.0 27.5 27.0 TUR- BID- ITY (NTU) 4.0 14 1.9 13 16 2.0 OXYGEN, DI8- SOLVBD (MG/L) 5.7 6.6 6.6 3.3 7.9 6.7 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 68 79 74 41 96 81 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 15 11 14 18 10 13 COLI- PORM, FECAL, 0.45 UM-MF (COLS. / 100 ML) 2800 3300 K7600 K7400 2900 K7000 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 590 K17000 300 570 290 60 DATE NOV 1991 04... JAN 1992 02.. . FBB 19... MAY 06.. . JUL 01... SEP 01... HARD- NESS CALCIUM TOTAL DIS- (MG/L SOLVED AS (MG/L MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L CAC03) AS CA) AS MG) AS NA) 160 48 10 37 190 57 12 58 160 46 10 35 SODIUM AD- SORP- TION RATIO 1 " -- 2 -- 1 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 1.6 — — 2.4 -- 1.6 ALKA- LINITY WAT WH TOT FET FIELD MG/L AS CACO3 150 105 180 160 115 140 8ULFIDB TOTAL (MG/L AS 8) <0.5 — — 0.6 — — SULFATB DIS- SOLVED (MQ/L AS 804) 63 — -- 85 -- 57 CHLO- RIDE, DIS- SOLVED (MG/L AS CL) 40 — ~ 54 — 34 DATE NOV 1991 04.. . JAN 1992 02. .. FBB 19.. . MAY 06.. . JUL 01.. . SEP 01... FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.20 -- -- 0.20 -- 0.20 SILICA, DIS- SOLVE! (MG/L AS SI02) 22 -- -- 20 -- 17 :DS, OF ITI- rrs. :s- ,VBD :/L) 312 •- - 385 - 288 SOLIDS, DIS- SOLVED (TONS PER DAY) 2.65 — — 4.98 -- 2.64 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 7 17 3 29 33 <1 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.390 0.660 0.250 0.470 0.043 0.056 NITRO- NXTRO- NITRO- NITRO- GEN, GEN, GEN, GEN, NITRITE NO2+NO3 AMMONIA ORGANIC TOTAL TOTAL TOTAL TOTAL (MG/L (MG/L (MQ/L (MG/L AS N) AS N) AS N) AS N) 7 17 3 29 33 <1 0.390 0.660 0.250 0.470 0.043 0.056 0.010 0.030 0.040 0.120 0.010 0.040 0.400 0.690 0.290 0.590 0.530 0.096 0.070 0.070 0.130 0.660 0.030 0.180 0.23 0.43 0.37 0.44 0.27 0.42 non-ideal count 406 RIO PORTUGOBS BASIN 50116200 RIO PORTUGUES AT PONCE, PR—Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE NOV 1991 04... JAN 1992 02... FEE 19... HAY 06... JUL 01... SEP 01... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.30 0.50 0.50 1.1 0.30 0.60 NITRO- GEN, TOTAL (MG/L AS N) 0.70 1.2 0.79 1.7 0.35 0.70 NITRO- GEN, TOTAL (MG/L AS N03) 3.1 5.3 3.5 7.5 1.6 3.1 PHOS- PHORUS ARSENIC TOTAL TOTAL (MG/L (UG/L AS P) AS AS) 0.020 <1 0.080 0.080 0.150 <1 0.010 0.150 BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 — -- <100 — -- BORON, TOTAL RECOV- ERABLE (UG/L AS B) 140 -- -- 160 -- -- CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 -- -- <1 -- — CHRO- MIUM, COPPER, TOTAL TOTAL RBCOV- RECOV- ERABLE BRABLB (UG/L (UG/L AS CR) AS CU) 1 50 __ __ 1 <10 __ __ DATE NOV 1991 04... JAN 1992 02... FBB 19... HAY OS.. . JUL 01... SBP 01.. . IRON, TOTAL RECOV- ERABLE (UG/L AS PB) LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) SELE- NIUM, TOTAL (UG/L AS SB) SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CYANIDE TOTAL (MG/L AS CN) PHENOLS TOTAL (UG/L) MBTHY- LBNB BLUB ACTIVE SUB- STANCE (MG/L) 380 1400 40 190 <0.10 <0.10 20 <0.010 <0.010 0.03 0.07 DATE JUL 1992 01... TIME 1145 PCB, TOTAL (UG/L) PESTICIDE ANALYSES ALDRIN, TOTAL (UG/L) <0.010 CHLOR- DANB, TOTAL (UG/L) DDD, TOTAL (UG/L) DDE, TOTAL (UG/L) DOT, TOTAL (UG/L) DI- AZINON, TOTAL (UG/L) <0.010 <0.010 <0.010 DI- ENDO- BLDRIN SULPAN, TOTAL TOTAL (UG/L) (UG/L) <0.01 <0.010 <0.010 DATE JUL 1992 01... DATE JUL 1992 01... ENDRIN WATER UNPLTRD RBC (UG/L) <0.010 PARA- THION, TOTAL (UG/L) BTHION, TOTAL (UG/L) <0.01 NAPH- THA- LENES, POLY- CHLOR. TOTAL (UG/L) HBPTA- CHLOR, TOTAL (UG/L) <0.010 PBR- THANE TOTAL (UG/L) HEPTA- CHLOR BPOXIDB TOTAL (UG/L) <0.010 TOX- APHBNB, TOTAL (UG/L) LINDANB TOTAL (UG/L) <0.010 TOTAL TRI- THION (UG/L) MALA- THION, TOTAL (UG/L) <0.01 2,4-D, TOTAL (UG/L) METH- OXY- CHLOR, TOTAL (UG/L) <0.01 2,4,5-T TOTAL (UG/L) METHYL PARA- THION, TOTAL (UG/L) <0.01 2, 4-DP TOTAL (UG/L) MIRBX, TOTAL (UG/L) <0.01 SILVBX, TOTAL (UG/L) <0.01 <0.10 <0.01 <0.01 <0.01 <0.01 <0.01 RIO GUAYANILLA BASIN 50124200 RIO OOAYANILLA NEAR OOAYANILLA, PR 407 LOCATION.--Lat 18°02'40" of Highways 2 and 132, Plaza de Quayanilla. , long 66°47'53', Hydrologie Unit 21010004, on left bank, 0.7 mi (1.1 km) north of junction 0.6 mi (1.0 km) downstream from Quebrada Consejo, 1.8 mi (2.9 km) north-northwest from DRAINAGE AREA.--18.9 mi* (49.0 km»). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--March 1981 to current year. GAGE.—Mater-stage recorder. Elevation of gage is 80 ft (24 m), from topographic map. REMARKS.--Records fair except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV JAN FBB MAR APR MAY JUN JUL SEP 1 22 33 2 29 30 3 23 25 4 22 24 5 22 24 6 25 70 7 33 36 8 23 30 9 21 28 10 27 27 11 24 26 12 21 25 13 19 24 14 20 28 15 30 24 16 22 26 17 20 38 18 24 27 19 33 22 20 28 20 21 39 20 22 35 19 23 43 19 24 44 19 25 55 20 26 46 26 27 35 23 28 34 22 29 32 23 30 32 20 31 36 TOTAL 919 798 MEAN 29.6 26.6 MAX 55 70 MIN 19 19 AC-FT 1820 1580 CPSM 1.57 1.41 IN. 1.81 1.57 e Estimated STATISTICS OF MONTHLY MEAN MEAN 64.7 53.2 MAX 167 110 (WY) 1986 1988 MIN 16.0 21.5 (WY) 1983 1989 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 19 18 18 21 19 17 17 18 19 18 16 15 14 15 16 17 18 18 18 18 22 19 19 18 18 17 17 16 16 16 16 543 17.5 22 14 1080 .93 1.07 DATA 20.1 41.9 1988 11.9 1989 FOR 14 14 12 11 69 408 53 32 21 16 16 22 12 9.8 8.6 9.4 19 11 9.5 8.6 8.6 8.4 8.4 7.0 6.8 6.8 6.2 5.9 5.9 5.9 5.5 851.3 27.5 408 5.5 1690 1.45 1.68 FOR WATER 11.1 27.5 1992 6.97 1991 5.4 5.4 5.2 5.2 5.4 5.4 eS.4 e5.9 e6.3 e6.3 6.1 6.5 e6.8 e6.1 6.3 6.3 6.0 5.4 5.4 5.4 5.5 5.4 5.0 .9 .6 .4 .5 .1 .1 ___ --- 158.7 5.47 6.8 4.1 315 .29 .31 YEARS 1981 7.18 11.4 1985 3.10 1990 4.8 5.0 4.4 4.2 4.5 4.9 5.7 5.4 5.2 eS.4 e6.4 e6.8 e3.5 e3.3 e3.3 e3.2 e3.2 e3.4 e3.8 e3.8 e4.0 e4.3 e3.6 e3.4 e3.6 e3.6 eS.O e9.0 elS e!3 elO 164.7 5.31 15 3.2 327 .28 .32 - 1992 6.20 13.2 1989 2.85 1981 1991 CALENDAR YEAR 5487. 15. 107 2. 2. 10880 . 10. 31 9. 3. 6 0 Sep 17 0 Jun 26 3 Apr 25 80 80 0 0 e20 e!9 e30 ell e6.0 eS.O e4.0 e3.4 eS.O e6.6 e7.0 e4.5 e4.8 eS.O e7.0 elO e!2 e!4 e!2 e2S e62 e40 e!9 e!4 e!2 elO e8.4 eB.O e7.0 e6.6 --- 398.3 13.3 62 3.4 790 .70 .78 e6.6 e7.0 e6.0 eS.6 eS.4 e9.0 e6.0 eB.O e3.9 e4.0 e4.0 e4.5 10 21 37 12 13 9.9 6.0 4.6 4.0 3.7 270 211 167 127 70 42 32 25 21 1153.2 37.2 270 3.7 2290 1.97 2.27 23 25 21 19 17 16 15 16 62 33 35 49 43 34 30 29 28 27 27 27 74 42 37 34 34 35 35 34 34 34 969 32.3 74 15 1920 1.71 1.91 30 27 30 21 20 17 15 16 15 10 8.4 13 7.3 57 50 12 7.3 7.5 12 20 9.3 8.1 7.3 6.7 6.2 5.8 5.3 5.2 5.3 5.2 6.3 466.2 15.0 57 5.2 925 .80 .92 10 6.1 7.3 5.9 50 80 21 14 23 22 15 134 111 42 28 25 18 14 11 9.9 23 28 13 10 9.1 8.0 7.6 7.2 9.7 13 7.6 783.4 25.3 134 5.9 1550 1.34 1.54 6.3 6.1 5.3 4.9 12 21 59 44 17 10 7.8 7.8 5.8 35 28 21 41 29 14 15 20 34 31 19 23 31 13 58 42 81--- 742.0 24.7 81 4.9 1470 1.31 1.46 , BY WATER YEAR (WY) 10.7 26.6 1983 4.39 1984 FOR 1992 7946. 21. 408 3. 3. 2170 11. 15760 1. 15. 37 16 4. 28.7 80.4 1985 5.83 1988 WATER YEAR 8 7 Jan 6 2 Mar 16 4 Mar 13 Jan 6 74 Jan 6 15 64 9 14.9 41.0 1987 3.28 1991 12.2 25.9 1986 5.22 1990 WATER 23 33 16 1500 1 14700 20 17150 1 17 51 10 3 18.4 48.5 1988 6.72 1985 YEARS 1981 .7 .1 .3 Oct . 97 Aug .7 Aug Sep .40 Sep .25 .01 .8 42.0 102 1981 7.46 1983 - 1992 1986 1983 7 1985 21 1990 15 1990 12 1982 12 1982 RIQ GUAYANILLA BASIN 50124700 RIO OUAYANILLA AT CENTRAL ROPINA, PR NATBR-QOALITY RECORDS LOCATION.--Lat 18°00'40", long 66°46'49", at dirt road bridge, 0.7 mi (1.1 km) from mouth, 0. east of Central Rufina and 0.9 id. (1.4 lea) southeast of Quayanilla. DRAINAGE AREA.--22.8 mi* (59.1 km*)- PERIOD OF RECORD.--Nater years 1960-65, 1974 to current year. NATBR-QOALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 9 mi (1.4 km) DATE OCT 1991 30... JAN 1992 02... FEB 19... MAY 20... JUL 01. .. SEP 02... TIME 1145 0950 0950 1135 1250 1300 DIS- CHARGE, INST. CUBIC FEET PER SECOND 12.6 0.90 0.98 1.8 2.7 2.1 SPE- CIFIC CON- DUCT- ANCE (OS /CM) 450 784 722 668 255 704 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.3 7.7 7.3 7.2 7.2 7.7 TEMPER- ATURE WATER (DBG C) 29.5 26.0 27.5 30.5 32.5 31.0 TUR- BID- ITY (NTU) 430 2.5 1.2 2.5 1.6 1.3 OXYGEN, DIS- SOLVED (MG/L) 5.5 2.4 3.8 6.2 8.0 7.1 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 72 35 48 82 97 92 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 71 20 22 24 16 13 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 42000 K50 K10 410 250 260 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 26000 K80 K10 350 200 260 DATE OCT 1991 30... JAN 1992 02... FBB 19.. . MAY 20.. . JUL 01... SBP 02.. . HARD- NESS CALCIUM TOTAL DIS- (MG/L SOLVED AS (MG/L MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L CAC03) AS CA) AS MG) AS NA) 240 51 28 150 240 65 18 55 230 64 19 39 ALKA- SODIUM POTAS- LINITY CHLO- AD- SIUM, NAT WH SULFATB RIDE, SORP- DIS- TOT FBT SULFIDB DIS- DIS- TION SOLVED FIELD TOTAL SOLVED SOLVED RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L AS K) 8.0 5.6 5.3 CACO3 150 260 220 170 180 170 AS S) AS 804) AS CL) <0.5 49 <0.5 71 34 28 54 53 SOLIDS, RESIDUE DATE OCT 1991 30... JAN 1992 02... FBB 19.. . MAY 20... JUL 01.. . SBP 02... FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.20 -- -- <0.10 -- 0.20 SILICA, DIS- SOLVED (MG/L AS SI 02) 18 -- -- 25 -- 30 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 422 -- -- 396 -- 406 SOLIDS, DIS- SOLVED (TONS PER DAY) 2.92 — -- 1.90 -- 2.30 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 978 3 7 4 18 4 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 2.06 0.070 2.10 7.53 0.66 8.98 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.740 0.770 1.10 0.070 0.540 0.020 NITRO- GEN, N02+N03 TOTAL (MG/L AS N) 2.80 0.840 3.20 7.60 1.20 9.00 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.160 8.70 2.80 0.080 3.10 0.070 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.84 0.80 0.70 0.72 1.3 0.63 K = non-ideal count RIO QUAYANILLA BASIN 50124700 RIO GUAYANILLA AT CENTRAL RUFINA, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 409 DATE OCT 1991 30... JAN 1992 02... PBB 19... MAY 20... JOL 01... SEP 02... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) NITRO- GEN, TOTAL (MG/L AS N) NITRO- GEN, TOTAL (MG/L AS N03) PHOS- PHORUS TOTAL (MG/L AS P) ARSENIC TOTAL (UG/L AS AS) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) BORON, TOTAL RECOV- ERABLE (UG/L AS B) CADMIUM TOTAL RECOV- ERABLE (UQ/L AS CD) CHRO- MIUM, TOTAL RECOV- ERABLE (UQ/L AS CR) COPPER, TOTAL RECOV- ERABLE (UQ/L AS CU) 1.0 9.5 3.5 0.80 4.4 0.70 3.8 10 6.7 8.4 5.6 9.7 17 46 30 ^7 25 43 0.890 3.20 2.70 2.70 0.54 2.50 200 <100 60 150 <1 66 <1 150 20 DATE OCT 1991 30... JAN 1992 02.. . FEE 19.. . MAY 20... JUL 01... SEP 02... IRON, TOTAL RECOV- ERABLE (UG/L AS FB) LEAD, TOTAL- RECOV- BRABLB (UG/L AS PB) MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) SELE- NIUM, TOTAL (UG/L AS SB) SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CYANIDE TOTAL (MG/L AS CN) PHENOLS TOTAL (UG/L) MBTHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 40000 150 17 1200 210 0.10 <0.10 <1 <1 <1 90 <0.010 20 <0.010 <1 <1 0.03 0.14 DATE JOL 1992 01... TIME 1250 PCB, TOTAL (UG/L) PESTICIDE ANALYSES ALDRIN, TOTAL (UG/L) <0.010 CHLOR- DANB, TOTAL (UG/L) ODD, TOTAL (UG/L) DDE, TOTAL (UG/L) DOT, TOTAL (UG/L) <0.010 <0.010 <0.010 DI- AZINON, TOTAL (UG/L) DI- BNDO- BLDRIN SULPAN, TOTAL TOTAL (UG/L) (UG/L) 0.03 <0.010 <0.010 DATE JOL 1992 01... ENDRIN WATER UNFLTRD BTHION, REC TOTAL (UG/L) (UG/L) HEPTA- HBPTA- CHLOR CHLOR, BPOXIDB LINDANB TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) <0.010 <0.01 <0.010 <0.010 <0.010 MALA- THION, TOTAL (UG/L) <0.01 MBTH- OXY- CHLOR, TOTAL (OG/L) <0.01 METHYL PARA- THION, TOTAL (UG/L) <0.01 MIRBX, TOTAL (UQ/L) <0.01 DATE JUL 1992 01.. . PARA- THION, TOTAL (UG/L) NAPH- THA- LENES, POLY- CHLOR. TOTAL (UG/L) PBR- THANB TOTAL (UG/L) TOX- APHENB, TOTAL (UG/L) TOTAL TRI- THION (UG/L) <0.01 <0.10 <1 <0.01 2,4-D, 2,4,5-T 2, 4-DP SILVBX, TOTAL TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) (UQ/L) <0.01 <0.01 <0.01 <0.01 470 RIO YAOCO BASIN 50125780 LAGO LOCCHETTI AT DAMSITB, PR LOCATION.--Lat 18°05'37", long 66°51'54", Hydrologic Unit 21010004, at Antonio Luccbetti DAB on Rio Yauco, 3.9 mi (6.3 km) nortb of Yauco. DRAINAGE ARKA.--17.4 mi 1 (45.1 km»). ELEVATION RECORDS PERIOD OP RECORD.--December 1989 to current year. GAGE.—Water-stage recorder. Datum of gage IB mean sea level. REMARKS.—Lago Lucchetti was completed in 1952. The dam IB on Rio Yauco and IB a unit of the Southwestern Puerto Rico Project. It provide* 16,500 acre-feet (20.3 hm?) of usable storage for power generation and irrigation. The dam IB a concrete gravity structure with a total length of 591 ft (180 m), a maximum height of 178 ft (54 m), and a maximum width at the base of 150 ft (46 m). An ungated, overflow type spillway with a clear length of 171 ft (52 m) and a crest elevation of 570 ft (174 m) , occupies the central portion of the dam. The spillway was designed for a maximum capacity of 62,800 ftVs (1,778 mVs) at a design head of 20 ft (6 m) . The dam is owned by Puerto Rico Electric Power Authority. Gage-height and precipitation satellite telemetry at station. EXTREMES OBSERVED FOR PERIOD OF RECORD.--Maximum elevation, 571.54 ft (174.21 m), Oct. 25, 1990 minis 519.85 ft (158.45 m), Oct. 23, 1991 but may have been less during period of no gage-height record. elevation, EXTREMES OBSERVED FOR CURRENT YEAR.--Maximum elevation, 566.85 ft (172.77 m), June 28; minimum elevation, 519.85 ft (158.45 m), Oct. 23, but may have been less during period of no gage-height record. Capacity Table (based on data from Puerto Rico Hater Resources Authority) Elevation, in feet 519 520 525 527 530 532 Contents, in acre-feet 2,275 2,385 2,965 3,255 3,695 3,975 Elevation, in feet 540 550 561 563 571 573 Contents, in acre-feet 5,165 7,020 9,600 10,125 12,125 12,645 ELEVATION (FEET NGVD), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY OBSERVATION AT 24:00 VALUES DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN OCT NOV DEC JAN FBB MAR APR MAY JDN JUL AUG SEP 533.15 533.18 531.76 531.70 531.70 531.72 532.07 529.78 529.00 530.11 530.20 527.50 527.50 527.50 527.52 527.70 525.08 525.03 525.02 524.08 524.08 520.96 519.85 A A A A A A A A A A A A A A A A A A A A A A A A A A A A 533.55 536.85 538.44 539.09 539.06 539.05 537.47 537.43 537.42 537.01 536.92 538.37 538.37 538.63 538.66 538.53 538.38 538.36 538.32 538.29 538.22 537.42 536.95 535.80 535.74 535.68 535.68 A A A A A A A A A A A A A A A A A A A A A 534.00 536.10 537.22 537.30 537.66 539.58 540.32 541.46 542.27 542.25 542.47 542.48 542.48 542.48 542.48 543.14 A A A A A A A A A A A 545.47 545.43 547.15 547.47 547.71 546.91 546.87 547.39 547.99 547.98 547.93 547.87 547.82 547.75 546.95 546.89 545.69 545.78 545.72 545.66 545.90 544.97 545.17 545.13 545.31 545.25 ___ ___ 545.65 546.34 546.45 547.78 549.42 549.03 548.98 548.92 549.45 550.00 550.94 551.57 552.87 554 . 17 556.10 557.36 557.39 557.33 556.93 556.91 557.51 557.53 557.52 557.53 557.52 557.49 557.49 557.47 557.45 557.42 556.40 556.43 556.43 556.07 556.00 555.96 555.30 555.25 555.19 555.15 553.97 554.68 554.47 554.35 554.45 554.46 554.21 554.27 554.55 554.88 556.42 557.19 557.48 557.50 557.36 557.38 557.38 557.39 556.93 555.87 555.02 ___ 554.28 554.25 554.02 553.67 553.63 553.33 553.03 552.61 552.56 552.50 552.20 551.89 551.18 551.01 550.13 550.15 550.20 548.64 549.44 549.47 549.56 549.00 553.84 555.89 557.27 557.35 A A A A A A A A 564.57 563.94 562.93 563.17 563.04 563.64 563.75 563.59 563.27 563.12 563.41 563.47 565.32 565.79 566.26 566.16 565.98 565.99 566.79 566.74 A 566.37 ___ 566.37 565.66 565.25 565.39 565.50 565.07 564.55 564.53 564.18 564.80 564.77 565.21 564.41 564.91 564.21 564.21 564.19 564.20 564.58 564.00 563.93 563.07 561.66 561.65 561.62 A 561.46 561.42 561.38 560.78 560.98 560.52 A A A A A A A A A A A A A A A A A 556.53 555.62 555.40 555.08 554.43 553.86 552.25 552.26 552.22 552.24 551.30 551.35 550.30 550.33 549.12 548.41 548.18 547.47 549.18 554.71 555.61 554.08 553.42 551.99 551.52 551.63 552.08 552.28 550.94 549.29 547.88 547.17 546.93 A A A A A A A A A A ___ --- 17164.92 16671.99 553.71 555.73 557.53 557.50 545.65 553.97 A No gage-height record. RIO LOCO BASIN 50129700 RIO LOCO AT GUANICA, PR HATER-QUALITY RECORDS LOCATION.--Lat 17»58'33", long 66°54'52-, 0.6 mi (1.0 km) northwest of Guanica and northeast of Bnsenada. DRAINAGE AREA.--Indeterminate. PERIOD OF RECORD.--Water years 1975 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 411 1.2 mi (1.9 km) OCT 30 DEC 18 FBB 19 MAY 20 JUN 26 SEP 02 OCT 30 DEC 18 FBB 19 MAY 20 JUN 26 SEP 02 OCT 30 DEC 18 FBB 19 MAY 20 JUN 26 SEP 02 DATE 1991 1992 DATE 1991 ... ... 1992 . . . DATE (00950) 1991 ... ... 1992 . . . TIME 1025 1345 0830 0925 0845 1120 HARD- NESS TOTAL (MG/L AS CAC03 ) 970 -- -- 190 -- 1000 FLUO- RIDB, DIS- SOLVED (MG/L AS P) (00955) 1.1 -- -- <0.10 -- 0.80 SPE- CIFIC CON- DUCT- ANCE (US/CM) 9700 6900 10000 17000 9500 44000 CALCIUM DIS- SOLVED (MG/L AS CA) 92 — — 35 -- 94 SILICA, DIS- SOLVED (MG/L AS SI02) (70301) 28 -- — 22 -- 27 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.5 7.7 7.2 7.3 7.7 7.8 MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) 180 -- -- 24 -- 190 SOLIDS, SUM OP CONSTI- TUENTS, DIS- SOLVED (MG/L) (00530) 4920 -- -- 550 -- 5180 TEMPER- ATURE WATER (DBG C) 30.5 25.5 25.5 28.0 29.0 31.0 SODIUM, DIS- SOLVED (MG/L AS NA) 1400 __ -- 130 -- 1500 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) (00620) 30 5 18 <1 28 26 TUR- BID- ITY (NTU) 6.4 2.6 2.2 6.5 4.0 2.0 SODIUM AD- SORP- TION RATIO 20 __ -- 4 -- 20 NITRO- GEN, NITRATE TOTAL (MG/L AS N) (00615) -- -- -- 0.076 0.087 -- OXYGEN, DIS- SOLVED (MG/L) 1.8 3.1 1.9 1.9 0.7 1.8 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 50 -_ — 7.3 -- 57 NITRO- GEN, NITRITE TOTAL (MG/L AS N) (00630) <0.010 <0.010 <0.010 0.010 0.010 <0.010 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 24 39 21 24 18 20 ALKA- LINITY WAT WH TOT FBT FIELD MG/L AS CACO3 250 190 260 110 255 220 NITRO- GEN, NO2+N03 TOTAL (MG/L AS N) (00610) 0.085 0.057 0.082 0.086 0.097 0.098 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 140 120 190 18 200 110 SULFIDE TOTAL (MG/L AS S) <0.5 -- -- <0.5 — "" NITRO- GEN, AMMONIA TOTAL (MG/L AS N) (00605) 0.050 0.030 0.090 0.040 0.060 0.050 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 210 K80 K140 580 290 230 SULFATE DIS- SOLVED (MG/L AS SO4) 420 -- -- 46 -- 460 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) (00625) 0.45 0.27 0.31 0.26 0.84 0.25 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 230 360 460 460 310 K145 CHLO- RIDE, DIS- SOLVED (MG/L AS CL) 2600 -- -- 220 -- 2700 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.50 0.30 0.40 0.30 0.90 0.30 K = non-ideal count 412 RIO LOCO BASIN 50129700 RIO LOCO AT QUANICA, PR—Continued HATER-QUALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 30... DEC 18... FBB 1992 19.. . MAY 20... JUN 26... SEP 02... NITRO- GEN, TOTAL (MG/L AS N) NITRO- GEN, TOTAL (MG/L AS N03) PHOS- PHORUS TOTAL (MG/L AS P) ARSENIC TOTAL (UG/L AS AS) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) BORON, TOTAL RECOV- ERABLE (UG/L AS B) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) IRON, TOTAL RECOV- ERABLE (UG/L AS FE) 0.59 0.36 0.48 0.39 1.0 0.40 2.6 1.6 2.1 1.7 4.4 1.8 0.150 0.060 0.150 0.030 0.270 0.100 <1 200 <100 700 70 60 10 1000 520 DATE OCT 1991 30... DEC 18.. . FBB 1992 19... MAY 20... JUN 26... SEP 02... LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) SELE- NIUM, TOTAL (UG/L AS SB) SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CYANIDE TOTAL (MG/L AS CN) PHENOLS TOTAL (UG/L) METHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 140 80 <0.10 <0.10 <0.010 <0.010 0.32 0.06 DATE JUN 1992 26.. . PESTICIDE ANALYSES TIME 0845 PCB, TOTAL (UG/L) ALDRIN, TOTAL (UG/L) <0.010 CHLOR- DANB, TOTAL (UG/L) DDD, TOTAL (UG/L) DDE, TOTAL (UG/L) DOT, TOTAL (UG/L) DI- AZINON, TOTAL (UG/L) <0.010 <0.010 <0.010 DI- BNDO- ELDRIN SULFAN, TOTAL TOTAL (UG/L) (UG/L) <0.01 <0.010 <0.010 DATE JUN 1992 26... ENDRIN WATER UNFLTRD ETHION, REC (UG/L) TOTAL (UG/L) HBPTA- CHLOR, TOTAL (UG/L) HEPTA- CHLOR EPOXIDE TOTAL (UG/L) LINDANB TOTAL (UG/L) •cO.010 <0.01 <0.010 <0.010 <0.010 MALA- THION, TOTAL (UG/L) •cO.Ol METH- OXY- CHLOR, TOTAL (UG/L) <0.01 METHYL PARA- THION, TOTAL (UG/L) <0.01 MIRBX, TOTAL (UG/L) <0.01 DATE JUN 1992 26.. . PARA- THION, TOTAi. (UG/L) NAPH- THA- LENES, POLY- CHLOR. TOTAL (UG/L) PER- THANB TOTAL (UG/L) TOX- APHENE, TOTAL (UG/L) TOTAL TRI- THION (UG/L) 2,4-D, TOTAL (UG/L) 2,4,5-T TOTAL (UG/L) 2, 4 -DP TOTAL (UG/L) SILVBX, TOTAL (UG/L) <0.01 <0.10 <0.01 0.11 <0.01 <0.01 •cO.Ol ri *,•..,.„„ * «.,«.>„.* *v 0123456 KILOMETERS 234 MILES -Map area f y f KHOJ^J """"V I MM* Lseo bavin EXPLANATION '** I A 138° SURFACE-WATER STATION AND NUMBER j V 1297 QUALITY-OF-WATER STATION AND NUMBER WELL AND WELL NUMBER Figure 25.~Rio Guanajibo basin. CO 414 RIO GUANAJIBO BASIN 50131990 RIO GUANAJIBO AT HWY 119 AT SAN GERMAN, PR LOCATION.—Lat 18°05'06", long 67°02'02", Hydrologic Unit 21010003, on right bank, at bridge on Hwy 119, 0.6 mi (1.0 km) southwest of junction of Highways 119 and 2, 0.22 mi (0.35 km) northeast of junction of Highways 119 and 102, 0.74 mi (1.19 km) east from public Plaza of San German. DRAINAGE AREA.--34.6 mi 1 (89.6 km1 ). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—April 1991 to current year. GAGE.—Hater-stage recorder. Elevation of gage is 148 ft (45.0 m), from topographic map. REMARKS.—Records fair except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN PEB MAR APR MAY JUN JUL AUG SEP 1 21 26 2 15 19 3 12 16 4 10 14 5 11 14 6 26 19 7 42 16 8 22 15 9 17 14 10 15 13 11 14 13 12 13 12 13 13 12 14 12 13 15 12 12 16 11 14 17 9.8 15 18 8.7 27 19 22 28 20 32 16 21 19 16 22 71 15 23 42 13 24 20 13 25 15 18 26 13 15 27 12 15 28 11 15 29 11 13 30 38 13 31 42 —— TOTAL 632.5 474 MEAN 20.4 15.8 MAX 71 28 MIN 8.7 12 MED 15 15 AC-FT 1250 940 CFSM .59 .46 IN. .68 .51 e Estimated 12 11 10 10 13 11 16 12 12 10 8.8 8.3 7.8 7.9 8.0 6.9 6.1 6.0 5.9 6.4 6.7 6.5 5.6 5.4 5.6 5.6 5.8 5.8 6.3 6.1 6.0 254.5 8.21 16 5.4 6.9 505 .24 .27 STATISTICS OF MONTHLY MEAN DATA MEAN 20.4 15.8 MAX 20.4 15.8 (WY) 1992 1992 MIN 20.4 15.8 (WY) 1992 1992 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 8.21 8.21 1992 8.21 1992 5.8 5.7 5.6 5.4 6.8 817 73 34 22 16 14 14 12 11 9.5 9.0 8.7 8.3 7.9 7.5 7.2 6.8 6.4 6.1 6.1 6.1 6.1 5.2 4.8 4.8 4.8 1157.6 37.3 817 4.8 7.2 2300 1.08 1.24 FOR WATER 37.3 37.3 1992 37.3 1992 5.1 e3.6 5.3 e4.2 5.1 e3.7 4.8 e3.7 4.7 e3 . 6 5.5 e3.3 6.2 e3.3 5.6 e3.1 5.2 e3.0 4.7 e2 . 9 .2 e3.0 .2 e3 . 0 .4 .3 .3 4.2 3.9 3.7 e3.6 e3.5 e3.5 e3.7 e3.6 e3.5 e3.7 e3.8 e3.7 e3.6 e3.6 —— --- 3.2 3.4 3.4 3.1 2.8 2.8 2.7 2.9 4.3 4.3 2.8 2.3 2.3 2.4 2.5 2.6 5.6 3.3 12 125.2 109.1 4.32 6.2 3.5 4.2 248 .12 .13 YEARS 1991 - 4.32 4.32 1992 4.32 1992 FOR 1992 7599. 20. 817 1. 3.52 12 2.3 3.1 216 .10 .12 1992 3.52 3.52 1992 3.52 1992 6.7 6.8 10 4.4 3.7 4.2 9.1 4.7 4.9 4.4 3.4 3.2 2.8 2.6 2.4 10 20 7.7 12 74 41 e35 e20 e!5 ell e8.8 eV.O e5.6 e4.6 e4.6 349.6 11.7 74 2.4 6.7 693 .34 .38 , BY WATER 11.7 11.7 1992 11.7 1992 eV.O e5.6 e4.3 e3.4 e2.9 e2.4 e2.0 el. 8 el. 5 el. 7 el. 5 el. 9 e2.4 e2.7 e2.3 e4.1 e7.6 e5.6 e3.0 e21 e8.2 24 539 199 140 120 87 68 56 48 41 1414.9 45.6 539 1.5 5.6 2810 1.32 1.52 YEAR (WY) 39.2 45.6 1992 32.8 1991 35 30 25 23 18 15 13 11 32 29 15 17 13 9.1 6.9 6.0 5.5 4.9 4.5 4.3 5.9 4.5 3.6 3.4 3.3 3.2 3.1 3.1 2.8 2.3 352.4 11.7 35 2.3 6.4 699 .34 .38 8.38 11.7 1992 5.01 1991 WATER YEAR 5 8 5 1.8 6610 13. 15070 . 8. 42 8. 2. 23 60 17 8 8 Jan 6 May 9 May 6 Jan 6 Jan 6 2.0 2.3 3.0 2.7 2.4 2.0 2.5 4.7 10 12 6.3 11 22 108 93 37 14 6.4 15 38 13 3.8 2.4 2.0 1.8 2.0 2.0 2.0 1.9 2.3 7.3 434.8 14.0 108 1.8 3.8 862 .41 .47 14.2 14.5 1991 14.0 1992 WATER 20 20 20 817 1 1 6610 13 15040 8 40 10 3 5.7 4.3 4.3 8.6 46 89 47 32 23 25 17 16 21 13 15 15 8.2 6.7 6.3 5.8 41 58 39 25 16 13 11 11 23 21 16 682.9 22.0 89 4.3 16 1350 .64 .73 21.8 22.0 1992 21.7 1991 YEARS 1991 .8 .8 .8 Jan .5 May .8 May Jan .23 Jan .60 .15 .2 12 29 59 58 60 162 206 80 46 30 50 29 44 52 44 28 29 34 35 126 52 42 38 29 41 29 29 36 46 57 --- 1612 53.7 206 12 43 3200 1.55 1.73 33.3 53.7 1992 12.9 1991 - 1992 1992 1992 6 1992 9 1992 6 1992 6 1992 6 1992 RIO GUANAJIBO BASIN 50133600 RIO GUANAJIBO NEAR SAN GERMAN, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°07'18", long 67°03'56", at bridge on Highway 347, 2.2 mi (3.5 km) DRAINAGE AREA.--45.5 mi> (117.8 km1 ). PERIOD OF RECORD.—Water years 1979 to current year. WATER QUALITY DATA, WATER YEARS OCTOBER 1991 TO SEPTEMBER 1992 415 northwest of San GerntAn. DIS- PH CHARGE, SPB- WATER INST. CIFIC WHOLE CUBIC CON- FIELD TEMPER- TOR- FEET DOCT- (STAND- ATORB BID- DATB TIME PER ANCR ARD WATER ITY SECOND (US/CM) ONITS) (DBG OCT 11 DEC 20 FBB 26 MAY 19 JUN 26 ADG 13 1991 1992 DATB OCT 1991 11.. . DBC 20.. . FEB 1992 26... MAY 19.. . JUN 26.. . AUG 13.. . DATB OCT 1991 11. .. DEC 20.. . FEB 1992 26.. . MAY 19.. . JUN 26.. . AUG 13.. . 1135 4 0840 5 1430 5 1130 4 0800 8 1030 8 HARD- NESS TOTAL (MG/L AS CACO3 ) 220 -- -- 200 -- 210 FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.30 -- -- <0.10 -- 0.10 .1 .6 .9 .6 .0 .7 CALCIUM DIS- SOLVED (MG/L AS CA) 23 -- -- 22 -- 22 SILICA, DIS- SOLVED (MG/L AS SI02) 34 -- -- 31 -- 32 646 660 720 517 665 556 MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) 39 -- -- 35 -- 37 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 382 -- -- 309 -- 302 7.9 27 8.0 24 7.5 29 7.1 28 7.7 24 7.4 27 SODIUM, DIS- SOLVED (MG/L AS NA) 43 -- -- 31 -- 27 SOLIDS, DIS- SOLVED (TONS PER DAY) 4.25 -- -- 3.84 -- 7.09 C) (NTU) .5 40 .5 4.2 OXYGEN, OXYGEN COLI- DIS- DEMAND, FORM, STREP- SOLVED CHEM- FECAL, TOCOCCI OXYGEN, (PER- ICAL 0.45 FECAL, DIS- CENT (HIGH UM-MF (COLS. SOLVED SATUR- LEVEL) (COLS./ PER (MG/L) ATI ON) (MG/L) 100 ML) 100 .0 0.80 .0 2.3 .5 0.70 .0 2.0 SODIUM AD- SORP- TION RATIO 1 -- -- 1 -- 0.8 RESIDUE TOTAL AT 105 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 3.1 -- -- 3.2 -- 2.6 NITRO- GEN, DBG. C, NITRATB SUS- PENDED (MG/L) 6 1 1 <1 7 1 TOTAL (MG/L AS N) 2.10 2.54 1.46 1.47 2.07 1.33 5.3 5.2 6.0 4.3 3.1 3.0 ALKA- LINITY WAT WH TOT FBT FIELD MG/L AS CACO3 - 215 120 230 190 240 190 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.200 0.160 0.040 0.130 0.230 0.270 19 38 72 55 44 41 SULFIDB TOTAL (MG/L AS S) <0.5 -- -- <0.5 -- "" NITRO- GEN, N02+NO3 TOTAL (MG/L AS N) 2.30 2.70 1.50 1.60 2.30 1.60 13 530 ML) 480 19 K140 2200 18 10 23 K180 13 430 <10 2000 CHLO- SULFATB RIDB, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS S04) AS CL) 64 47 __ __ 31 42 __ 37 35 NITRO- NITRO- GEN, GEN, AMMONIA ORGANIC TOTAL TOTAL (MG/L (MG/L AS N) AS N) 0.490 0.51 0.340 0.46 0.060 0.34 0.150 0.45 0.260 0.44 1.00 0.50 230 390 210 280 non-ideal count 416 RIO GUANAJIBO BASIN 50133600 RIO GOANAJIBO NEAR SAN GERMAN, PR--Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 11... DEC 20... FEB 1992 26... MAY 19... JUN 26... AUG 13.. . NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 1.0 0.80 0.40 0.60 0.70 1.5 NITRO- GEN, TOTAL (MG/L AS N) 3.3 3.5 1.9 2.2 3.0 3.1 NITRO- GEN, TOTAL (MG/L AS N03) 15 15 8.4 9.7 13 14 PHOS- PHORUS ARSENIC TOTAL TOTAL (MG/L (UG/L AS P) AS AS) 1.50 <1 1.40 1.20 0.770 1 0.840 0.670 BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) 100 -- -- <100 -- -- BORON, TOTAL RECOV- ERABLE (UG/L AS B) 650 -- -- 90 -- -- CHRO- CADMIUM MIUM, COPPER, TOTAL TOTAL TOTAL RBCOV- RBCOV- RECOV- ERABLE ERABLB ERABLB (UG/L (UG/L (UG/L AS CD) AS CR) AS CU) <1 4 20 __ __ <1 2 30 __ — DATE OCT 1991 11.. . DEC 20... FBB 1992 26.. . MAY 19... JUN 26.. . AUG 13.. . IRON, TOTAL RECOV- ERABLE (UG/L AS FE) LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS UN) MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) SELE- NIUM, TOTAL (UG/L AS SB) SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CYANIDE TOTAL (MG/L AS CN) PHENOLS TOTAL (UG/L) MBTHY- LBNB BLUE ACTIVE SUB- STANCE (MG/L) 520 220 80 70 <0.10 <0.10 30 30 <0.010 <0.010 0.07 0.08 RIO GOANAJIBO BASIN SO 136400 RIO ROSARIO NEAR HORMXOUBROS, PR 417 LOCATION.--Lat 18<>09'36*, long 67°05'08", Hydrologic Unit 21010003 at bridge on Highway 348, 0.5 mi (0.8 Xa) southwest of RoBaric plaza. DRAINAGE AREA.--18.3 mi» (47.4 Xm»). HATER-DISCHARGE RECORDS PERIOD OP RECORD.--October 1985 to current year. GAGE.—Hater-stage recorder. Elevation of gage is 50.0 ft (15.2 a), from topographic Bap. REMARKS.--Records fair except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JON JUL AUO SEP 1 59 36 2 34 23 3 27 20 4 23 19 5 21 21 6 42 20 7 68 18 8 117 17 9 65 16 10 36 16 11 28 16 12 25 IS 13 23 15 14 26 IS IS 28 IS 16 21 IS 17 19 IS 18 20 IS 19 27 14 20 32 13 21 32 13 22 26 12 23 21 16 24 19 IS 25 19 13 26 18 13 27 17 13 28 31 12 29 26 12 30 27 11 31 S3 TOTAL 1030 484 MEAN 33.2 16.1 MAX 117 36 MXN 17 11 AC-PT 2040 960 CPSM 1.82 .88 IN. 2.09 .98 e Estimated STATISTICS OP MONTHLY MEAN MEAN 105 74.2 MAX 206 117 (HY) 1986 1990 KIN 33.2 16.1 (WY) 1992 1992 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK PLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW PLOW ANNUAL RUNOFF (AC-PT) ANNUAL RUNOFF (CPSM) ANNUAL RUNOPP (INCHES) 10 PERCENT EXCEEDS SO PERCENT EXCEEDS 90 PERCENT EXCEEDS 11 11 11 12 11 11 10 10 9.8 9.7 10 9.4 9.3 9.0 8.7 8.8 9.5 9.7 9.9 10 13 9.7 9.7 9.7 9.5 9.3 9.3 9.2 9.1 9.1 9.1 307.5 9.92 13 8.7 610 .54 .63 DATA 30.6 43.2 1990 9.92 1992 POR 12 10 9.0 8.8 9.7 163 27 16 13 12 13 14 12 11 11 11 12 11 11 11 11 11 11 elO elO elO elO elO •10 9.5 9.4 509.4 16.4 163 8.8 1010 .90 1.04 POR WATER 20.5 31.8 1990 15.9 1991 9.3 8.7 8.8 9.1 9.2 11 14 11 9.1 8.7 9.3 8.7 8.4 8.4 8.7 8.3 8.2 8.1 7.9 7.6 7.7 7.6 7.5 7.4 7.3 7.1 7.0 6.9 7.0 ___ —— 248.0 8.55 14 6.9 492 .47 .50 YEARS 1986 15.2 19.1 1987 8.55 1992 7.5 7.9 8.1 8.2 8.7 7.9 7.7 9.5 7.3 7.5 7.4 7.3 7.3 7.0 6.9 6.9 7.1 8.6 7.7 7.3 7.3 7.2 6.4 6.2 6.5 6.7 8.3 21 IS 16 60 314.4 10.1 60 6.2 624 .55 .64 - 1992 22.3 77.0 1989 10.1 1992 1991 CALENDAR YEAR 9427. 25. 362 6. 7. 18700 1. 19. 52 16 9. 0 8 Sep 21 8 Apr 29 5 Apr 24 41 16 8 27 19 11 7.5 6.1 5.4 5.6 6.7 8.6 11 8.1 6.8 6.6 5. 5 35 46 27 11 9.8 43 45 27 12 8.3 6.6 6.0 5.8 5.2 4.9 6.0 --- 433.5 14.4 46 4.9 860 .79 .88 6.5 6.3 5.2 4.8 4.5 4.4 4.1 4.2 3.9 4.1 4.1 4.4 4.7 4.6 5. 5 9.7 8.4 5.4 47 33 10 IS 275 196 85 45 26 18 18 30 40 932.8 30.1 275 3.9 1850 1.64 1.90 27 18 14 12 10 9.5 8.9 9.8 28 35 18 13 11 10 10 9.8 9.7 9.5 9.2 8.5 8.7 8.7 8.0 7.9 7.8 7.8 7.5 7.5 7.7 7.1 ___ 359.6 12.0 35 7.1 713 .66 .73 6.8 7.4 13 7.8 7.5 7.1 7.0 7.5 13 13 14 10 79 129 91 SO 28 IS 105 93 28 18 15 68 31 17 13 12 11 30 23 970.1 31.3 129 6.8 1920 1.71 1.97 17 13 12 113 94 148 69 167 189 169 89 77 76 51 54 37 31 27 24 23 23 25 22 20 37 28 19 17 30 73 41 1815 58.5 189 12 3600 3.20 3.69 24 71 81 198 107 158 135 122 109 84 145 100 281 199 128 91 71 58 79 225 136 187 136 76 71 58 47 113 81 502 —— 3873 129 502 24 7680 7.05 7.87 , BY HATER YEAR (WY) 23.5 57.7 1989 11.9 1991 POR 1992 11277 30 502 3 4 5640 12 3 22370 1 22 81 12 6 40.5 99.1 1986 15.8 1990 HATER YEAR .3 .8 Sep 30 .9 May 9 .2 May 6 Sep 30 .54 Sep 30 .7 May 9 .68 .92 .9 44.3 79.0 1989 12.0 1992 43.8 75.2 1989 23.2 1990 WATER 48 67 30 1550 3 4 7480 13 3 34830 2 35 112 26 10 61.2 102 1989 25.1 1991 YEARS 1986 - .1 .9 .8 Oet 7 .9 May 9 .2 May 6 Aug 24 .64 Aug 24 .7 May 9 .63 .70 94.1 143 1989 32.7 1986 1992 1989 1992 1985 1992 1992 1988 1988 1992 418 RIO GUANAJIBO BASIN 50136400 RIO ROSARIO NEAR HORMIOOEROS, PR--Continued HATER-QUALITY RECORDS PERIOD OF RECORD.--HATER YEARS 1979 TO CURRENT YEAR. PERIOD OF DAILY RECORD.— SUSPENDED-SEDIMENT DISCHARGEt OCTOBER 1985 TO SEPTEMBER 1986 INSTRUMENTATION.--US D-49 SEDIMtNT SAMPLER SINCE OCTOBER 1985. AUTOMATIC SEDIMENT SAMPLER SINCE 1986 REMARKS.--sediment samples were collected by a local observer once daily during low flow and more than once daily during high flow events for concentration and particle aize analyses. Sediment samples are collected periodically by survey ataff. Automatic sediment sampler aet to collect samples above 200 cfa. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATIONSi Maximum daily mean. 8,150 mg/L October 7. 1985; Minimum daily mean, 1 mg/L January 28, 1990. SEDIMENT LOADSt Maximum daily, 74,700 tona (67,800 tonnes) October 7, 1985; Minimum daily, 0.05 ton (0.04 Tonne) aeveral daya. EXTREMES FOR CURRENT YEAR.-- SEDIMENT CONCENTRATIONSi Maximum daily mean, 3,540 mg/L September 30. 1992; Minimum daily mean, 2.0 n aeveral daya. SEDIMENT LOADSt Maximum daily, 24.300 tona (22,000 tonnea) September 30. 1992; Minimum daily 0.04 ton (0.08 tonne) few daya. HATER-QUALITY DATA. HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 I/L DATE OCT 1991 11... DEC 19.. . FEB 1992 26... MAR 31.. . JUN 25... AUG 14... TIME 0915 1150 1310 1355 1230 0825 DIS- CHARGE, INST. CUBIC FEET PER SECOND 30 9.8 7.3 6.1 7.6 47 SPE- CIFIC CON- DUCT- ANCE (US /CM) 268 291 287 255 260 270 PH WATER WHOLE FIELD (STAND- ARD UNITS ) 8.3 7.3 8.4 7.0 8.0 7.6 TEMPER- ATURE WATER (DEQ C) 23.5 23.0 25.5 26.0 28.0 23.5 TUR- BID- ITY (NTU) 2.5 1.5 1.1 18 9.4 15 OXYGEN, DIS- SOLVED (MG/L) 8.4 9.7 4.7 7.4 9.1 8.0 OXYGEN. OXYGEN DIS- DEMAND, SOLVED CHEM- (PER- ICAL CENT (HIGH SATUR- LEVEL) ATION) (MG/L) 72 <10 89 <10 64 <10 53 <10 81 <10 72 <10 COLI- FORM, FECAL, 0.45 UM-MF (COLS . / 100 ML) 4200 310 70 K760 580 460 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 5000 K110 60 K410 430 660 HARD- NESS TOTAL (MG/L AS CACO3) 130 -- -- 110 -- 120 DATE CALCIUM DIS- SOLVED (MG/L MAGNE- SIUM, DIS- SOLVED (MG/L SODIUM. DIS- SOLVED (MG/L SODIUM AD- SORP- TION RATIO POTAS- SIUM. DIS- SOLVED (MG/L ALKA- LINITY WAT WH TOT FBI FIELD MG/L A! AS CA) AS MG) AS NA) OCT 1991 11... 22 DEC 19... FEB 1992 26... MAR 31... 21 JUN 25... AUG 14... 21 18 7.0 9.9 AS K) 0.3 1.8 0.4 1.4 0.3 1.4 130 52 120 100 135 130 SULFATE SOLFIDE DIS- TOTAL SOLVED (MG/L (MG/L AS S) AS S04) AS CL) AS F) CHLO- RIDE, DIS- SOLVED (MG/L FLUO- RIDE, DIS- SOLVED (MG/L SILICA, DIS- SOLVED (MG/L AS SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED <0.5 6.8 <0.5 11 SIO2) 13 <0.10 29 13 <0.10 27 7.8 <0.10 28 (MO/L) 176 158 162 non-ideal count RIO GUANAJIBO BASIN 50136400 RIO ROSARIO NEAR HORMIGUEROS, PR--Continu«d MATER QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 479 DATE OCT 1991 11... DEC 19. .. FEB 1992 26... MAR 31... JUN 25... AUG 14... DATE OCT 1991 11.. . DEC 19.. . FEB 1992 26... MAR 31... JUN 25... AUG 14... SOLIDS. DIS- SOLVED (TONS PER DAY) 14.3 — -- 2.59 -- 20.6 CHRO- MIUM. TOTAL RECOV- ERABLE (UO/L AS CR) 7 -- -- 3 -- -- RESIDUE TOTAL AT 105 DEG. C, SUS- PENDED (MO/L) <1 1 1 12 20 25 COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) <10 -- -- <10 -- -- NITRO- GEN, NITRATE TOTAL (MO/L AS N) — 0.480 — 0.640 0.210 0.710 IRON, TOTAL RECOV- ERABLE (UG/L AS FE) 200 -- -- 1200 -- — NITRO- GEN, NITRITE TOTAL (MO/L AS N) •cO.010 0.010 •cO.010 0.020 0.010 0.010 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) 4 -- -- <1 -- -- NITRO- GEN. N02+N03 TOTAL (MG/L AS N) 0.320 0.490 0.200 0.660 0.220 0.720 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) 20 -- -- 50 -- -- NITRO- GEN, AMMONIA TOTAL (MG/L AS N) <0.010 0.010 0.020 0.050 0.020 0.030 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) <0.10 _- -- 0.20 -- -- NITRO- GEN. AM- MONIA + ORGANIC TOTAL (MG/L AS N) <0.20 <0.20 <0.20 <0.20 <0.20 <0.20 SELE- NIUM, TOTAL (UO/L AS SE) <1 __ — <1 — -- PHOS- PHORUS ARSENIC TOTAL TOTAL (MO/L (UG/L AS P) AS AS) 0.010 <1 0.040 0.040 0.050 <1 0.030 0.020 SILVER, ZINC, TOTAL TOTAL RECOV- RECOV- ERABLE ERABLE (UG/L (UO/L AS AG) AS ZN) <1 <10 __ -_ <1 <10 __ -- BARIUM, BORON, TOTAL TOTAL RECOV- RECOV- ERABLE ERABLE (UG/L (UG/L AS BA) AS B) <100 40 — __ <100 <10 — CYANIDE TOTAL PHENOLS (MO/L TOTAL AS CN) (UO/L) •cO.010 3 -- _- <0.010 3 -- __ CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 -- -- <1 -- METHY- LENE BLUE ACTIVE SUB- STANCE (MO/L) 0.02 __ _- 0.02 -- -- 420 RIO GUANAJIBO BASIN 50136400 RIO ROSARIO NEAR HORMXGOBROS, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) OCTOBER 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 59 34 27 23 21 42 68 117 65 36 28 25 23 26 28 21 19 20 27 32 32 26 21 19 19 18 17 31 26 27 53 124 41 15 10 10 105 208 304 32 8 7 4 3 17 31 3 2 5 31 57 49 33 10 5 9 11 8 48 51 41 92 22 3.9 1.1 .62 .57 57 53 236 7.5 .81 .52 .26 .16 2.3 3.4 .20 .10 .32 3.7 9.0 6.3 3.0 .57 .26 .46 .53 .35 11 4.0 8.4 21 NOVEMBER TOTAL 1030 458.33 36 23 20 19 21 20 18 17 16 16 16 15 15 15 15 15 15 15 14 13 13 12 16 15 13 13 13 12 12 11 484 81 18 8 12 18 36 8 5 4 4 5 4 4 6 5 6 6 5 12 8 6 6 14 13 12 9 7 7 7 5 9.5 1.2 .44 .61 1.5 4.1 .41 .21 .16 .19 .22 .18 .18 .25 .20 .23 .25 .19 .45 .29 .20 .20 .79 .56 .45 .31 .26 .25 .23 .16 24.17 MEAN DISCHARGE (CFS) 11 11 11 12 11 11 10 10 9.8 9.7 10 9.4 9.3 9.0 8.7 8.8 9.5 9.7 9.9 10 13 9.7 9.7 9.7 9.5 9.3 9.3 9.2 9.1 9.1 9.1 307.5 MEAN CONCEN- TRATION (MG/L) DECEMBER 5 5 3 3 5 11 13 5 3 3 3 3 3 4 4 4 10 13 7 28 15 4 5 5 5 4 4 3 13 5 4 SEDIMENT DISCHARGE (TONS/DAY) .15 .14 .09 .10 .14 .33 .37 .15 .08 .08 .08 .08 .09 .10 .10 .09 .27 .34 .17 .78 .57 .10 .13 .12 .13 .09 .10 .08 .32 .12 .09 5.58 RIO GHANAJIBO BASIN 50136400 RIO ROSARIO NEAR HORMIGOEROS, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 421 MEAN DISCHARGE DAY (CPS) 1 2 3 4 S 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 12 10 9.0 8.8 9.7 163 27 16 13 12 13 14 12 11 11 11 12 11 11 11 11 11 11 elO elO elO elO elO elO 9.5 9.4 MEAN MEAN CONCBN- SEDIMENT MEAN CONCBN- SEDIMENT TRATION DISCHARGE DISCHARGE TRATION DISCHARGE (MG/L) (TONS/DAY) (CFS) (MG/L) (TONS/DAY) JANUARY 19 16 7 10 10 1290 39 9 5 4 6 7 8 5 10 7 4 4 3 6 5 3 3 3 3 2 2 3 3 3 11 FEBRUARY .83 .48 .17 .24 .27 1180 3.5 .41 .19 .14 .21 .27 .25 .16 .30 .22 .14 .11 .10 .18 .17 .09 .09 .08 .07 .06 .05 .07 .08 .08 .26 9.3 8.7 8.8 9.1 9.2 11 14 11 9.1 8.7 9.3 8.7 8.4 8.4 8.7 8.3 8.2 8.1 7.9 7.6 7.7 7.6 7.5 7.4 7.3 7.1 7.0 6.9 7.0 ___ ___ 3 4 15 8 7 7 4 4 5 6 10 9 4 4 3 2 2 2 2 3 8 5 3 9 4 3 3 5 5 ___ .08 .11 .37 .20 .17 .22 .19 .12 .12 .15 .25 .21 .11 .10 .08 .06 .04 .04 .05 .06 .18 .12 .08 .18 .09 .06 .05 .09 .11 ___ MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MARCH 7.5 7.9 8.1 8.2 8.7 7.9 7.7 9.S 7.3 7.5 7.4 7.3 7.3 7.0 6.9 6.9 7.1 8.6 7.7 7.3 7.3 7.2 6.4 6.2 6.5 6.7 8.3 21 15 16 60 5 3 4 8 10 5 4 2 3 10 6 6 6 5 6 8 4 29 42 12 4 10 10 10 6 4 6 33 35 24 208 .11 .06 .08 .20 .24 .11 .08 .06 .06 .21 .12 .12 .12 .09 .11 .15 .09 .66 .90 .24 .08 .19 .18 .18 .11 .07 .37 3.0 2.8 1.6 120 TOTAL 509.4 1189.27 248.0 3.69 314.4 132.39 e Estimated 422 RIO G0ANAJIBO BASIN 50136400 RIO ROSARIO NEAR HORMIG0BROS, PR—Continued SEDIMENT DISCHARGE, SOSPBNDBD (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 27 19 11 7.5 6.1 5.4 5.6 6.7 8.6 11 8.1 6.8 6.6 5.5 35 46 27 11 9.8 43 45 27 12 8.3 6.6 6.0 5.8 5.2 4.9 6.0 ___ APRIL 200 154 88 157 88 40 39 30 36 38 26 20 21 19 108 109 69 79 60 233 97 59 31 20 29 21 25 29 33 21 ___ MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MAY 18 9.1 2.6 3.2 1.5 .62 .59 .52 .85 1.1 .58 .39 .36 .30 40 26 6.2 2.4 1.6 93 18 4.7 1.1 .46 .52 .35 .39 .42 .45 .30 ___ 6.5 6.3 5.2 4.8 4.5 4.4 4.1 4.2 3.9 4.1 4.1 4.4 4.7 4.6 5.5 9.7 8.4 5.4 47 33 10 15 275 196 85 45 26 18 18 30 40 17 24 23 19 16 24 16 18 18 19 24 25 25 24 24 38 17 8 221 64 13 21 1380 757 203 74 37 23 24 68 74 .29 .39 .33 .25 .20 .28 .18 .19 .19 .21 .27 .31 .32 .29 .36 1.2 .44 .12 178 13 .34 1.9 1430 485 54 9.5 2.8 1.1 1.2 14 13 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) JUNE 27 18 14 12 10 9.5 8.9 9.8 28 35 18 13 11 10 10 9.8 9.7 9.5 9.2 8.5 8.7 8.7 8.0 7.9 7.8 7.8 7.5 7.5 7.7 7.1 --- 38 24 16 14 12 10 9 21 59 71 26 45 47 75 62 58 61 60 67 64 63 30 18 18 16 17 16 22 22 19 3.1 1.2 .60 .44 .32 .25 .21 .56 13 12 1.3 1.5 1.4 2.1 1.7 1.5 1.6 1.6 1.6 1.5 1.5 .72 .40 .38 .34 .35 .34 .46 .46 .37 --- TOTAL 433.5 235.60 932.8 2209.66 359.6 52.80 RIO GUANAJIBO BASIN 423 50136400 RIO ROSARIO NEAR HORMIGOBROS, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DAY (CPS) (MG/L) (TONS/DAY) (CPS) (MG/L) (TONS/DAY) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 TOTAL YEAR 6.8 7.4 13 7.8 7.5 7.1 7.0 7.5 13 13 14 10 79 129 91 50 28 15 105 93 28 18 15 68 31 17 13 12 11 30 23 970.1 11283.3 JULY 19 18 55 43 24 22 20 21 34 86 74 62 493 763 303 174 127 105 556 281 46 23 18 219 52 21 36 24 17 68 97 —— MEAN DISCHARGE (CPS) AUGUST i .35 .38 1.8 .93 .50 .42 .37 .44 1.4 3.1 2.9 1.8 420 834 125 47 10 4.2 463 109 3.8 1.1 .69 103 5.8 .96 1.3 .79 .52 18 5.5 2168.05 48672.95 17 13 12 113 94 148 69 167 189 169 89 77 76 51 54 37 31 27 24 23 23 25 22 20 37 28 19 17 30 73 41 1815 63 15 24 985 283 504 149 993 719 469 202 184 168 62 81 31 26 29 24 18 24 31 25 23 103 133 61 24 135 248 123 —— 3.3 .50 .81 1500 116 253 32 1760 428 270 57 49 47 9.6 13 3.1 2.1 2.1 1.6 1.1 1.6 2.1 1.5 1.2 29 10 3.2 1.1 21 91 14 4724.91 24 71 81 198 107 158 135 122 109 84 145 100 283 199 128 91 71 58 79 225 136 187 136 76 71 58 47 113 81 506 3879 MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) SEPTEMBER 24 71 81 198 107 158 135 122 109 84 145 100 283 199 128 91 71 58 79 225 136 187 136 76 71 58 47 113 81 506 63 377 298 649 201 1260 347 392 242 183 818 118 1920 974 263 199 51 30 207 725 453 912 240 19 104 65 12 357 184 3540 4 233 78 827 75 1180 154 283 85 80 614 39 5820 584 102 50 10 4 73 844 191 1290 110 3 24 12 1 347 49 24300 .2 .9 .9 .5 37468.5 424 RIO GUANAJIBO BASIN 50136400 RIO ROSARIO NEAR HORMIGUBROS, PR--Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 PARTICLB-SIZB DISTRIBUTION OF SUSPENDED SEDIMENT DATE JAN 1992 06. .. APR 02... MAY 23... JUL 14. .. AUG 04... 04. .. 08. .. SEP 30. .. TIME 0410 1934 1115 2055 1708 1710 1703 1826 DIS- CHARGE, INST. CUBIC FEET PER SECOND 605 33 552 520 855 859 57 1085 SEDI- MENT, SUS- PENDED (MG/L) 5600 2020 4170 4000 20300 19600 15300 23900 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 9150 180 6200 5620 46900 45400 2360 70000 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM 36 46 41 38 28 29 16 6 SED. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM 49 58 46 48 41 41 30 8 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 58 64 62 59 56 55 36 10 JAN 1992 06. .. APR 02. .. MAY 23... JUL 14. .. AUG 04. .. 04. .. 08... SEP 30. .. SBD. SUSP. FALL DIAM. PERCENT FINER THAN 016 MM 69 78 72 69 70 68 46 SED. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM 79 80 79 79 83 77 62 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 94 96 95 97 95 92 77 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 98 97 99 99 99 98 94 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 99 99 100 100 99.8 99 98 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 99.6 99.6 100 100 100 99.7 99 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM ?00 100 100 100 100 100 99 12 14 19 22 26 31 45 RIO OUANAJIBO BASIN 50136400 RIO ROSARIO NEAR HORMIOOBROS , PR--Continued HATER QUALITY DATA, HATER YEAR OCTOBER 1991 TO SBPTBMBBR 1992 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT 425 DATE OCT 1991 08... NOV 01... DEC 20... JAN 1992 06... MAR 28.. . APR 16... 20... MAY 23.. . 23... JUL 14... 14.. . 30... AUG 04.. . 04.. . 08... 10.. . SEP 02... 04.. . 20... 27... 30... TIME 1731 1825 1920 0440 1540 1908 1955 0945 1430 1956 2010 1907 1725 1740 1710 1846 1848 1500 1602 1816 1834 STREAM- FLOW, INSTAN- TANEOUS (CFS) 238 28 11 504 12 98 234 475 393 525 512 138 681 563 1140 364 395 475 755 45 1020 SEDI- MENT, SUS- PENDED (MQ/L) 233 41.6 43.7 4670 123 302 2440 3580 2000 6980 6750 430 12200 12100 15300 1110 3180 10100 7180 6250 9070 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 149 3.1 1.3 6350 14 80 1540 4590 2120 9890 9330 160 22400 18400 47000 1090 3390 12900 14650 759 24900 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 93 100 100 95 86 97 99 95 98 97 98 97 93 88 78 88 80 79 67 48 49 426 RIO GOANAJIBO BASIN 50138000 RIO GOANAJIBO NEAR HORMIOUEROS, PR LOCATION.--Lat 18°08'36*, long 67°08'S7*, Hydrologic Unit 21010003, at bridge on Highway 100, 1.4 mi (2.3 km) west of Hormigueros, and 2.0 mi (3.2 km) downatream from Rio Rosario. DRAINAGE AREA.--120 mi* (311 km*). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—Annual low-flow measurements 19S9, monthly measurements April 19S9 to November 1967, January 1973 to current year. GAGE.—Water-stage recorder. Datum of gage is at mean sea level. Previous to Nov. 7, 1980, at site 0.3 mi (O.S km) upstream at datum 7.36 ft (2.243 m) higher. REMARKS.--Record* fair. Gage-height and precipitation satellite telemetry at station. Daily discharges affected by sewage treatment plant about 2.1 mi (3.4 km) upstream from gage. DAY DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES OCT NOV JAN FBB MAR APR MAY JUN JUL AUG SEP 1 164 97 2 102 73 3 87 64 4 80 61 5 73 60 6 73 71 7 16S 64 8 170 57 9 146 51 10 92 48 11 78 45 12 69 43 13 63 41 14 60 32 15 69 32 16 61 27 17 53 38 18 49 31 19 62 50 20 135 32 21 139 32 22 174 25 23 191 26 24 103 36 25 84 27 26 73 29 27 66 23 28 66 23 29 80 22 30 61 21 31 136 TOTAL 3024 1281 MEAN 97 . 5 42.7 MAX 191 97 MIN 49 21 AC-FT 6000 2540 CPSM .81 .36 IN. .94 .40 22 19 17 19 17 24 29 22 19 19 15 13 12 13 11 9.8 8.8 7.5 13 15 19 16 14 12 14 12 12 12 14 13 13 476.1 15.4 29 7.5 944 .13 .15 STATISTICS OF MONTHLY MEAN DATA MEAN 489 442 MAX 1254 1518 (WY) 1986 1978 MIN 97.5 42.7 (WY) 1992 1992 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 130 422 1976 15.4 1992 FOR 14 18 10 11 12 939 555 210 162 130 110 97 82 69 62 58 55 52 47 43 39 36 33 30 28 30 27 24 23 21 19 3046 98.3 939 10 6040 .82 .94 FOR WATER 56.8 108 1982 13.8 1973 20 20 22 22 24 25 36 32 27 23 29 31 26 26 24 23 21 21 20 19 19 20 20 19 20 21 20 20 19 669 23.1 36 19 1330 .19 .21 YEARS 1973 44.8 95.9 1974 13.9 1977 20 19 23 20 20 20 18 18 17 16 17 15 14 14 14 14 14 16 17 15 15 22 15 10 11 13 12 35 20 50 13 557 18.0 50 10 1100 .15 .17 - 1992 45.0 244 1989 10.6 1977 1991 CALENDAR YEAR 23702. 64. 572 7. 11 47010 . 7. 130 47 18 1 9 May 8 5 Dec 18 Dec 12 54 35 119 44 69 30 18 13 28 42 28 43 25 17 14 11 9.1 65 111 52 49 139 313 202 85 61 46 36 28 23 19 19 1758.1 58.6 313 9.1 3490 .49 .55 29 23 18 14 12 9.9 8.2 7.5 6.3 7.0 6.2 8.0 9.7 11 9.5 18 32 23 12 87 34 109 1550 2170 950 654 423 284 219 185 180 7109.3 229 2170 6.2 14100 1.91 2.20 196 156 105 89 74 63 57 52 85 145 99 73 64 52 45 40 35 32 29 26 26 24 20 16 17 18 17 17 16 17 1705 56.8 196 16 3380 .47 .53 16 15 26 19 17 15 14 26 60 69 41 37 83 267 448 119 97 62 78 248 101 71 84 90 88 52 42 39 35 37 67 2463 79.5 448 14 4890 .66 .76 60 45 41 93 118 192 127 140 247 204 134 126 186 107 104 86 68 61 54 49 51 100 64 54 49 67 45 40 49 102 99 2962 95.5 247 40 5880 .80 .92 52 56 150 450 514 588 888 576 448 299 425 326 493 877 604 399 327 274 252 598 646 409 407 276 648 532 283 327 337 497 --- 12958 432 888 52 25700 3.60 4.02 , BY WATER YEAR (WY) 71.0 316 1989 16.1 1977 FOR 1992 38008 104 2170 6 7 2760 20 75390 11 269 39 13 182 636 1980 12.7 1977 WATER YEAR .5 May 24 .2 May 11 .6 May 7 May 23 .14 May 23 .87 .78 111 504 1979 9.23 1977 107 240 1984 26.4 1976 WATER 204 402 104 35000 5 5 128000 28 4 148000 1 23 450 76 20 233 757 1988 42.3 1976 YEARS 1973 Sep .0 Jun .5 Jun Sep .50 Sep .6 Jun .70 .14 507 2075 1975 95.4 1991 - 1992 1979 1992 16 1975 18 1977 17 1977 16 1975 16 1975 22 1977 RIO GUANA JI BO BASIN 50138000 RIO OOANAJIBO NEAR HORMIGOBROS, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1958 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 427 DATE OCT 1991 10. .. DEC 19. .. FEB 1992 26... MAR 31. .. JUN 25. .. AUG 14. .. TIME 1015 0925 1015 1125 1100 1010 DIS- CHARGE, INST. CUBIC FEET PER SECOND 97 16 24 15 24 145 SPE- CIFIC CON- DUCT- ANCE (US/CM) 350 446 484 410 470 343 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.8 7.0 7.6 7.4 7.4 7.4 TEMPER- ATURE WATER (DBG C) 25.0 22.5 24.0 25.0 25.5 26.0 TUR- BID- ITY (NTU) 15 5.0 1.7 5.9 3.3 17 OXYGEN, DIS- SOLVED (MG/L) 6.9 6.4 6.5 6.5 7.0 5.7 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 83 70 78 80 91 74 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 17 15 14 11 11 <10 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K640 K850 K170 500 520 2200 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) K880 420 440 380 300 K900 DATE OCT 1991 10.. . DEC 19.. . FEB 1992 26.. . MAR 31.. . JUN 25. . . AUG 14... HARD- NESS CALCIUM TOTAL DIS- (MG/L SOLVED AS (MG/L MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L CACO3) AS CA) AS MG) AS NA) 170 26 25 13 170 24 27 20 150 25 22 11 SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY CHLO- SIUM, WAT WH SULFATE RIDE, DIS- TOT FET SULFIDE DIS- DIS- SOLVED FIELD TOTAL SOLVED SOLVED (MG/L MG/L AS (MG/L (MG/L (MG/L AS K) 0.4 1.8 0.7 2.4 0.4 2.2 CACO3 170 100 200 160 220 150 AS S) AS SO4) AS CL) <0.5 13 <O.S 27 15 16 27 14 SOLIDS, DATE OCT 1991 10.. . DEC 19.. . FEB 1992 26.. . MAR 31. . . JUN 25.. . AUG 14... FLUO- RIDE, DIS- SOLVED (MG/L AS F) <0.10 -- -- <0.10 -- 0.10 SILICA, DIS- SOLVED (MG/L AS 8102) 29 -- -- 30 -- 26 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 226 -- -- 253 -- 200 RESIDUE DIS- AT 105 NITRO- NITRO- NITRO- NITRO- NITRO- GEN, GEN, GEN, GEN, GEN, SOLVED DBG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL PER PENDED (MG/L (MG/L (MG/L (MG/L (MG/L (MG/L) AS N) AS N) AS N) AS N) AS N) DAY) <1 2 1 15 8 40 -- — — 0.310 0.710 0.520 <0.010 <0.010 <0.010 0.010 0.010 0.020 0 0 0 0 0 0 .590 .610 .120 .320 .720 .540 0. 0. 0. 0. 0. 0. 020 010 020 020 030 040 0. — 0. 0. 0. 0. 18 18 18 17 36 non-ideal count 428 RIO GUANAJIBO BASIN S0138000 RIO GUANAJIBO NEAR HORMIGUBROS, PR—Continued WATBR-QOALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 10... DEC 19... FEE 1992 26... MAR 31... JON 25... AUG 14... DATE OCT 1991 10... DEC 19.. . PBB 1992 26.. . MAR 31. . . JON 25... AUG 14... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.20 <0.20 0.20 0.20 0.20 0.40 IRON, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N) 0.79 — 0.32 O.S2 0.92 0.94 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS NO3) 3.5 -- 1.4 2.3 4.1 4.2 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.180 0.390 0.320 0.280 0.340 0.270 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) ARSENIC TOTAL (UG/L AS AS) <1 -- -- <1 -- -- SELE- NIUM, TOTAL (UG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 — — <100 — -- SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) 60 -- -- 40 -- -- ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) 1 — — <1 — -- CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) 10 -- -- 3 -- -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CO) 10 — — <10 — -- MBTHY- LBNB BLOB ACTIVE SUB- STANCE (MG/L) 1200 S40 70 70 <0.10 <0.10 20 <0.010 <0.010 0.02 0.02 DATE JON 1992 25... TIME 1100 PCB, TOTAL (UG/L) PESTICIDE ANALYSES ALDRIN, TOTAL (UG/L) <0.1 <0.010 CHLOR- DANB, TOTAL (UG/L) DDD, TOTAL (UG/L) DDE, TOTAL (OG/L) DOT, TOTAL (UG/L) <0.010 <0.010 <0.010 DI- AZINON, TOTAL (UG/L) DI- ENDO- BLDRIN SOLPAN, TOTAL TOTAL (UG/L) (UG/L) <0.01 <0.010 <0.010 DATE JON 1992 25... ENDRIN WATER ONPLTRD BTHION, RBC (UG/L) TOTAL (UG/L) HBPTA- HBPTA- CHLOR CHLOR, BPOXIDB LINDANB TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) <0.010 <0.01 <0.010 <0.010 <0.010 MALA- THION, TOTAL (UG/L) <0.01 MBTH- OXY- CHLOR, TOTAL (UG/L) <0.01 METHYL PARA- THION, TOTAL (UG/L) <0.01 MIRBX, TOTAL (OG/L) <0.01 DATE JON 1992 25.. . PARA- THION, TOTAL (UG/L) NAPH- THA- LENES, POLY- CHLOR. TOTAL (UG/L) PBR- THANB TOTAL (UG/L) TOX- APHENB, TOTAL (UG/L) TOTAL TRI- THION (UG/L) 2,4-D, TOTAL (UG/L) 2,4,5-T TOTAL (UG/L) 2, 4-DP TOTAfc (UG/L) SILVBX, TOTAL (00/L) <0.01 <0.10 <0.01 0.06 <0.01 <0.01 <0.01 EXPLANATION 1440 SURFACE-WATER STATION AND NUMBER V 1388 QUALITY-OF-WATER STATION AND NUMBER • 1415 LAKE-ELEVATION STATION < 0123458 KILOMETERS 01 234 MILES Figure 26:-Rfo Yaguez and Rio Grande de Anasco basins. 430 RIO YAOOBZ BASIN 50138800 RIO YAGUBZ NEAR MAYAGUBZ, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°12'31", long 67°07'07", at steel-truss bridge on unnumbered paved road about 800 ft (244 m) south of Highway 106, 1.8 mi (2.9 km) west of Highways 106 and 352 junction, and 1.4 mi (2.3 km) east-northeast from Mayaguez plaza. DRAINAGE AREA.--6.7 mi' (17.3 km1 ). PERIOD OF RECORD.--Hater years 1979 to current year. HATER-QUALITY DATA. HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 10... DEC 19.. . FBB 1992 26... MAY 19... JUN 24... AUO 13.. . DATE OCT 1991 10.. . DEC 19.. . PBB 1992 26... MAY 19.. . JUN 24... AUO 13.. . DATE OCT 1991 10.. . DEC 19.. . FBB 1992 26... MAY 19.. . JUN 28.. . AUO 13.. . TIME 1350 1430 1130 0910 1300 1240 CALCIUM DIS- SOLVED (MO/L AS CA) 33 -- -- 35 -- 33 SOLIDS, DIS- SOLVED (TONS PER DAY) 2.15 -- -- 0.85 -- 20.3 DIS- CHARGE, INST. CUBIC FEET PER SECOND 4.1 1.3 1.2 1.6 2.2 4.4 MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) 10 -- -- 9.5 -- 9.1 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) <1 4 1 2 3 11 SPE- CIFIC CON- DUCT- ANCE (US /CM) 294 227 322 314 300 273 SODIUM, DIS- SOLVED (MG/L AS NA) 11 -- -- 14 -- 10 NITRO- GEN, NITRITE TOTAL (MG/L AS N) •cO.010 •cO.010 •cO.010 •cO.010 •cO.010 •cO.010 PH HATER WHOLE FIELD (STAND- ARD UNITS) 8.0 7.4 7.8 8.2 7.8 7.1 SODIUM AD- SORP- TION RATIO 0.4 -- -- 0.5 -- 0.4 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 0.670 0.480 0.320 0.260 0.360 0.820 TEMPER- TUR- ATURB BID- WATER ITY (DBG C) (NTU) 26.0 2.0 25.5 0.60 23.0 0.50 25.5 2.0 26.0 1.5 24.5 1.3 ALKA- POTAS- LINITY SIUM, HAT HH DIS- TOT FBT SOLVED FIELD (MG/L MG/L AS AS K) CACO3 2.7 130 120 140 2.5 110 200 2.0 110 NITRO- NITRO- GEN, AM- GEN, MONIA + AMMONIA ORGANIC TOTAL TOTAL (MG/L (MG/L AS N) AS N) •cO.010 <0.20 •cO.010 <0.20 0.020 <0.20 •cO.010 <0.20 <0.010 <0.20 0.030 <0.20 OXYGEN, DIS- SOLVED (MG/L) 7.6 6.8 8.8 6.9 6.8 7.7 SULFIDB TOTAL (MG/L AS S) <0.5 -- -- <0.5 — -- PHOS- PHORUS TOTAL (MG/L AS P) 0.040 0.050 0.040 0.050 0.040 0.030 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 93 82 106 80 79 98 SULFATB DIS- SOLVED (MG/L AS S04) 14 -- -- 9.9 -- 7.8 ARSENIC TOTAL (UG/L AS AS) <1 -- -- <1 -- -- OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) <10 <10 <10 <10 <10 <10 CHLO- RIDE, DIS- SOLVED (MG/L AS CL) 15 -- -- 12 -- 9.0 BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) 100 -- -- <100 -- -- COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 350 240 220 280 210 290 FLUO- RIDB, DIS- SOLVED (MG/L AS P) <0.10 -- -- <0.10 -- <0.10 BORON, TOTAL RECOV- ERABLE (UG/L AS B) 50 -- -- 40 -- -- STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 690 280 360 340 200 K190 SILICA, DIS- SOLVED (MG/L AS SIO2) 30 -- -- 30 -- 29 CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 — — <1 -- -- HARD- NESS TOTAL (MG/L AS CACO3 ) 120 -- -- 140 -- 120 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 194 -- -- 196 -- 171 CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) <1 -- -- <1 -- — K = non- ideal count RIO YAGOEZ BASIN 50138800 RIO YAGUBZ NEAR MAYAGUBZ, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 431 DATE OCT 1991 10... DEC 19... FEB 1992 26... MAY 19... JUN 28... AUG 13. .. COPPER, TOTAL RECOV- ERABLE (UG/L AS CO) <10 -- -- 20 -- -- IRON, TOTAL RECOV- ERABLE (UG/L AS FB) 90 -- -- 130 -- -- LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) 3 -- -- <1 -- -- MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) 20 -- -- 20 -- -- MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) <0.10 -. -. <0.10 -- -- SELE- NIUM, TOTAL (UG/L AS SB) <1 .. .. <1 -- -- SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) <1 -- -_ <1 -- -- ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) <10 -- -. 20 -- -- CYANIDE TOTAL PHENOLS (MG/L TOTAL AS CN) (UG/L) <0.010 1 .. .. <0.010 <1 __ __ MBTRY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 0.02 -- -- 0.02 -- -- 432 RXO GRANDB DB ANASCO BASIN 50141500 LACK) GUAYO NEAR CASTANBR, PR LOCATION.--Lat 18°12'46", long 66°SO'06", Hydrologic Unit 21010003, at Ouayo Dam on Rio Guayo, 1.1 mi (1.8 km) southwest of Lago Yahuecas, 2.6 mi (4.2 km) southwest of Lago Prieto, 2.1 mi (3.4 km) north of Castafier, and 6.0 mi (9.6 km) west of Adjuntas. DRAINAGE AREA.--9.60 mi' (24.86 km1 ). ELEVATION RECORDS PERIOD OF RECORD.--April 1980 to January 1985, June 1989 to current year. GAGE.--Water-stage recorder. Datum of gage is mean sea level. REMARKS.--Lago Guayo was completed in 1956. The dam is on Rio Guayo and is the largest in the southwestern Puerto Rico project. The maximum storage is 17,400 ac-ft (21.5 hm3 ) for power and irrigation. The dam is a concrete gravity structure with a total length of 555 ft (169 m), a maximum structural height of 190 ft (58 m), and a maximum width at the base of 145 ft (44 m). The ungated overflow spillway with a crest elevation of 60.00 ft (18.29 m) and a crest length of 220 ft (67 m) was designed to pass a maximum flood of 30,200 ftVs (855 mVs) at a reservoir elevation of 70.00 ft (21.34 m). Timber flashboards that were added to increase storage capacity were subsequently removed and their use discontinued. Gage-height and precipitation satellite telemetry at station. EXTREMES OBSERVED FOR PERIOD OF RECORD.--Maximum elevation, 1462.43 ft (445.75 m), May 27, 1980; minimum elevation recorded, 1415.43 ft (431.42 m), June 2, 1990, but may have been less during period of no gage-height record June 2-5, 1990. EXTREMES OBSERVED FOR CURRENT YEAR.--Maximum elevation, 1455.96 ft (443.78 m), May. 27; minimum elevation recorded 1434.06 ft (437.10 m), Aug. 24. Capacity Table (based on data from Puerto Rico Water Resources Authority) Elevation, in feet 1415 1449 Contents, in acre-feet 3,960 10,660 Elevation, in feet 1460 1465 Contents, in acre-feet 13,550 15,000 ELEVATION (FEET NGVD), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY OBSERVATION AT 24:00 VALUES DAY OCT NOV DEC JAN FBB MAR APR 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN MAX MIN 1436.28 1436.82 1437.04 1436.81 1437.12 1438.33 1439.19 1440.49 1440.91 1440.92 1441.30 1441.63 1441.94 1442.51 1442.91 1443.26 1443.51 1443.93 1444.47 1444.89 1444.97 1444.98 1446.23 1445.96 1445.27 1445.63 1445.88 1445.89 1446.34 1446.16 1446.18 1442.51 1446.34 1436.28 A A A A A A A A A A A A A 1445.60 1445.97 1446.17 1446.41 1446.69 1446.87 1446.75 1446.00 1445.42 1444.38 1443.71 1443.94 1444.15 1444.36 1444.58 1444.79 1444.68 --- ___ ___ ___ 1444.84 1443.34 1443.52 1443.50 1443.60 1443.65 1443.71 1443.56 1443.67 A A A A A A A A A A A A A A A A 1446.37 1446.36 1446.32 1446.22 1446.20 1446.02 ___ ___ ___ 1445.05 1444.92 1444.98 1445.11 1446.38 A A A 1452.50 1452.31 1452.48 1452.59 1451.77 1451.54 1450.99 A A A A A A A A 1450.30 1450.59 1450.75 1450.94 1451.15 1450.27 1449.48 1449.20 ___ 1449.25 1449.47 1449.62 1449.78 1449.95 1449.00 1449.13 1449.29 1449.43 1449.61 1448.84 1447.87 1448.00 1448.20 1448.36 1448.54 1448.70 1448.87 1448.98 1449.11 1449.17 1449.30 1449.50 1449.34 1449.52 1449.48 1448.91 1448.15 1448.27 --- 1449.02 1449.95 1447.87 1448.07 1447.97 1447.96 1447.92 1444.30 1443.28 1443.40 1444.69 1444.69 1443.92 1443.35 1442.22 1440.62 A A A A A A A A A A A A A A A A A A ___ ___ ___ MAY JON JUL AUG SEP A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A 1437.00 1437.12 1437.10 1436.86 1437.00 1437.03 1437.03 1436.91 1436.95 1437.33 1437.85 1440.10 A A A A A A A 1454.69 1455.50 1455.27 1455.08 1454.97 1454.43 1453.93 1453.26 1453.00 A A A A A A A A A A A A A A A A A A A A A A A A A A A A ___ A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A A 1437.50 1436.89 1435.55 1434.60 1434.24 1434.29 1434.88 1435.38 1435.84 1436.21 1436.59 1437.11 1437.55 1437.97 1438.25 1438.52 1439.04 1439.47 1440.83 1441.68 1442.26 1442.63 1442.90 1443.14 1443.34 1443.94 1444.31 1444.52 1444.76 1444.97 1446.73 1447.54 1448.41 1449.02 1449.52 1449.95 1450.23 1450.55 1450.86 1451.05 1452.32 1452.78 1454.54 1445.53 1454.54 1437.97 A No gage-height record RIO GRANDB DE AKASCO BASIN 433 50143000 RIO GRANDE DB ANASCO NEAR LARES, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°15'26", long 66°55'00", at bridge on Highway 124, 0.7 mi (1.1 km) downstream from confluence of Rio Blanco and Rio Prleto, and 3.7 mi (6.0 km) southwest of Lares plaxa. DRAINAGE AREA.--26.3 mi' (68.1 km>) this does not include 36.2 mi' (93.8 km') which contributes only during high floods, and 3.5 mi> (9.1 km1 ) which contributes only part of its storm runoff. PERIOD OF RECORD.--Water years 1959-68, 1970 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 OCT 22 JAN 10 FEE 18 APR 07 JUL 02 SEP 03 OCT 22 JAN 10 FBB 18 APR 07 JDL 02 SEP 03 OCT 22 JAN 10 FBB 18 APR 07 JDL 02 SEP 03 K = DATE 1991 . . . 1992 . . . . . . DATE 1991 1992 DATE 1991 1992 . . . . . . . . . ... non- ideal TIME 1145 1430 1500 0930 0835 0845 HARD- NESS TOTAL (MG/L AS CACO3 ) 85 -- -- 130 -- 120 PLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.10 -- -- 0.20 -- 0.10 count DIS- CHARGE, INST. CUBIC FEET PER SECOND 153 23 13 16 18 31 CALCIUM DIS- SOLVED (MG/L AS CA) 23 — -- 35 -- 33 SILICA, DIS- SOLVED (MG/L AS SI02) 28 -- -- 31 -- 29 SPE- CIFIC CON- DUCT- ANCE (US/CM) 220 322 298 318 304 286 MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) 6.8 -- -- 9.6 -- 8.9 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 145 -- -- 208 -- 187 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.7 8.0 8.4 7.8 7.6 7.2 SODIUM, DIS- SOLVED (MG/L AS NA) 9.0 -- -- 14 -- 12 SOLIDS, DIS- SOLVED (TONS PER DAY) 60.1 -- -- 8.99 -- 10.6 TEMPER- ATURE WATER (DBG C) 26.0 25.5 27.0 24.5 26.0 24.0 SODIUM AD- SORP- TION RATIO 0.4 -- -- 0.5 -- 0.5 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 32 4 4 14 32 <1 TUR- BID- ITY (NTU) 54 2.7 1.5 3.5 0.90 13 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 2.3 -- — 2.3 -- 2.4 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 1.57 1.28 — 0.540 0.790 -- OXYGEN, DIS- SOLVED (MG/L) 8.2 7.4 9.4 10.0 7.0 7.0 ALKA- LINITY WAT WH TOT FET FIELD MG/L AS CACO3 72 110 120 120 130 100 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.030 0.020 < 0.010 0.020 0.010 <0.010 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 14 <10 <10 <10 <10 <10 SULFIDB TOTAL (MG/L AS S) <0.5 -- — <0.5 -- " NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 1.60 1.30 0.480 0.560 0.800 1.10 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 200000 280 410 K27 K45 1400 SULPATE DIS- SOLVED (MG/L AS 804) 22 -- -- 27 -- 24 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.060 0.020 0.030 0.060 0.020 0.020 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 5700 340 470 58 K91 230 CHLO- RIDE, DIS- SOLVED (MG/L AS CL) 11 -- -- 17 -- 13 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.44 -- -- 0.14 1.3 0.18 434 RIO GRANDS DB ANASCO BASIN 50143000 RIO GRANDB DB ANASCO NEAR LARES, PR—Continued WATER-QUALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 22... JAN 1992 10.. . FBB 18... APR 07... JUL 02.. . SEP 03.. . DATE OCT 1991 22.. . JAN 1992 10... FBB 18... APR 07... JUL 02.. . SEP 03.. . NITRO- GEN, AM- MONIA 4 ORGANIC TOTAL (MG/L AS N) 0.50 <0.20 <0.20 0.20 1.3 0.20 IRON, TOTAL RECOV- ERABLE (OG/L AS FE) 2800 -- -- 220 -- -- NITRO* GEN, TOTAL (MG/L AS N) 2.1 -- -- 0.76 2.1 1.3 LEAD, TOTAL RECOV- ERABLE (OG/L AS PB) 7 -- -- 2 -- -- NITRO- GEN, TOTAL (MG/L AS N03) 9.3 -- -- 3.4 6.3 5.8 MANGA- NESE, TOTAL RECOV- ERABLE (OG/L AS MN) <10 -- -- 30 -- -- PHOS- PHORUS ARSENIC TOTAL TOTAL (MG/L (OG/L AS P) AS AS) 0.100 2 0.050 0.050 0.020 <1 0.050 0.050 MERCURY TOTAL SELB- RBCOV- NIUM, BRABLB TOTAL (OG/L (OG/L AS HG) AS SB) <0.10 <1 __ __ <0.10 <1 __ -- BARIUM, TOTAL RECOV- ERABLE (OG/L AS BA) <100 -- — <100 -- -- SILVER, TOTAL RECOV- ERABLE (OG/L AS AG) <1 -- -- <1 — -- BORON, TOTAL RECOV- ERABLE (OG/L AS B) 50 -- -- 10 -- — — ZINC, TOTAL RECOV- ERABLE (OG/L AS ZN) <10 -- -- 10 -- -- CHRO- CADMZUM MIUM, TOTAL TOTAL RECOV- RECOV- ERABLE BRABLB (UG/L (UG/L AS CD) AS CR) <1 1 __ __ <1 1 __ — — - — CYANIDE TOTAL PHENOLS (MG/L TOTAL AS CN) (UG/L) <0.010 1 __ — <0.010 4 _. __ COPPER, TOTAL RECOV- ERABLE (UG/L AS CO) 10 -- -- 10 -- - — MBTHY- LBNB BLUB ACTIVE SUB- STANCE (MG/L) 0.02 — -- 0.03 -- — RIO GRANDB DB ANASCO BASIN 50144000 RIO GRANDB DB ANASCO NEAR SAN SEBASTIAN, PR 435 LOCATION.--Lat 18°17'05", long 67 0 03'05", Hydrologic Unit 21010003, on right bank, at downstream side of bridge on Highway 108, 0.4 mi (0.6 km) downstream from Quebrada La Zumbadora, 4.4 mi (7.1 km) northwest of Las Marias, 5.4 mi (8.7 km) southwest of San Sebastian. DRAINAGE AREA.--94.3 mi" (244.2 km1 ), does not include 36.2 mi 1 (93.8 km1 ) which contributes only during high floods, and 3.5 mi 1 (9.1 km 1 ) which contributes only part of its storm runoff. WATER-DISCHARGE RECORDS PERIOD OP RECORD.--March 1963 to current year. GAGE.--Water-stage recorder. Datum of gage is 103.72 ft (31.614 m) above mean sea level (Puerto Rico Department of Public Works bench mark). Previous to Oct. 30, 1975, at site 600 ft (180 m) upstream at same datum. REMARKS.--Records fair except those for estimated daily discharges, which are poor. Transbasin diversion (except during floods) to Rio Yauco basin for hydroelectric power and irrigation above Lago Guayo, Yahuecas, and Prieto, combined useable storage 17,300 acre-ft (21.3 hm5 ) . Limited storm runoff is contributed to basin by 3.5 mi* (9.1 km 1 ) above Rio Toro Diversion dam. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES NOV DEC JAN PBB APR MAY JUN JUL AUG SEP 1 273 565 2 240 317 3 231 271 4 210 270 5 200 247 6 200 236 7 360 219 8 343 209 9 382 203 10 239 254 11 210 210 12 196 194 13 268 188 14 238 185 15 261 179 16 196 176 17 178 174 18 958 168 19 886 161 20 669 156 21 1240 156 22 1100 148 23 779 138 24 343 136 25 395 134 26 268 134 27 234 129 28 239 132 29 224 142 30 379 126 31 722 TOTAL 12661 5957 MEAN 408 199 MAX 1240 565 MIN 178 126 AC-FT 25110 11820 CFSM 4.33 2.11 IN. 4.99 2.35 e Estimated STATISTICS OF MONTHLY MEAN MEAN 647 450 MAX 1094 746 (WY) 1991 1982 MIN 344 199 (WY) 1983 1992 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN- DAY MINIMUM INSTANTANEOUS PEAK FLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) 121 119 117 118 114 111 109 109 107 105 105 103 101 101 elOO 98 98 98 96 98 138 104 98 95 94 92 91 90 86 84 84 3184 103 138 84 6320 1.09 1.26 DATA 223 482 1966 103 1992 FOR 103 106 85 82 83 1940 256 137 112 103 101 100 96 92 88 94 90 89 86 86 85 82 81 79 81 81 80 77 79 79 74 4807 155 1940 74 9530 1.64 1.90 FOR WATER 139 215 1970 83.6 1965 73 69 68 68 68 67 81 71 65 58 57 57 56 54 52 55 57 56 55 e54 67 65 62 62 62 64 65 60 59 ___ --- 1807 62.3 81 52 3580 .66 .71 YEARS 1963 105 161 1981 62.3 1992 60 60 54 54 57 57 57 75 60 62 63 62 56 50 49 47 49 57 51 47 47 45 43 41 43 46 47 92 292 265 151 2239 72.2 292 41 4440 .77 .88 - 1992 98.1 271 1972 54.4 1965 1991 CALENDAR YEAR 94938 260 2690 58 66 188300 2. Aug 5 Apr 23 Apr 18 76 324 221 122 83 65 56 54 59 173 421 428 160 126 93 85 161 212 152 593 283 157 175 109 89 78 71 68 64 59 60 --- 4801 160 593 54 9520 1.70 1.89 69 80 76 64 59 56 71 56 52 52 81 139 173 85 75 77 99 616 1990 911 312 277 2260 1870 856 * 604 380 552 715 485 835 14027 452 2260 52 27820 4.80 5.53 563 388 249 192 170 292 563 1400 466 1230 511 244 173 349 185 160 134 116 107 101 105 103 89 94 82 78 76 72 72 68 --- 8432 281 1400 68 16720 2.98 3.33 67 67 94 107 104 66 62 59 66 71 75 87 75 285 374 175 97 202 101 526 207 123 102 257 278 126 128 149 121 90 1310 6151 198 1310 59 12200 2.10 2.43 403 184 136 364 410 494 455 231 338 345 280 173 164 174 139 126 128 123 110 154 549 489 256 221 515 378 185 138 125 128 128 8043 259 549 110 15950 2.75 3.17 782 354 206 162 170 640 1480 2150 772 1570 621 367 449 676 337 423 312 370 345 493 348 224 533 321 376 243 204 469 701 4510 --- 20608 687 4510 162 40880 7.28 8.13 , BY WATER YEAR (WY) 144 313 1971 49.3 1968 FOR 1992 92717 253 4510 41 45 21400 13 40 183900 2 357 1084 1986 63.7 1967 WATER YEAR Sep 30 Mar 24 Mar 20 Sep 30 .35 Sep 30 Mar 24 .69 284 815 1979 71.2 1977 282 657 1979 111 1990 WATER 308 460 189 19400 32 35 140000 33 31 223300 3 366 936 1979 152 1967 YEARS 1963 Sep Apr Apr Sep .90 Sep Apr .27 611 1422 1984 206 1983 - 1992 1979 1967 16 1975 18 1965 14 1965 16 1975 16 1975 19 1965 436 RIO GRANDS DB ANASCO BASIN 50144000 RIO GRANDE DB ANASCO NEAR SAN SEBASTIAN, PR--Continued (National stream-quality accounting network station) WATER-QUALITY RECORDS PERIOD OF RECORD.—Water years 1963 to current year WATER QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE OCT 1991 31. .. JAN 1992 29... APR 23... JUL 15. .. DATE OCT 1991 31. .. JAN 1992 29. .. APR 23. .. JUL 15. .. DATE OCT 1991 31... JAN 1992 29. .. APR 23. .. JUL 15. .. DATE OCT 1991 31. . . JAN 1992 29. .. APR 23. .. JUL 15. .. TIME 0950 1035 1020 1005 HARD- NESS NONCARB WH WAT TOT PLD MG/L AS CACO3 -- -- -- -- SOLIDS, RESIDUE AT 180 DEG. C DIS- SOLVED (MG/L) 127 151 108 124 ALUM- INUM, DIS- SOLVED (UG/L AS AL) 100 <10 80 90 DIS- CHARGE, INST. CUBIC FEET PER SECOND 351 73 107 420 CALCIUM DIS- SOLVED (MG/L AS CA) 19 29 20 20 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 120 169 143 121 ARSENIC DIS- SOLVED (UG/L AS AS) -- -- -- -- SPE- CIFIC CON- DUCT- ANCE (US/CM) 175 260 245 230 MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) 6.4 9.7 5.4 7.5 SOLIDS, DIS- SOLVED (TONS PER DAY) 114 33 41 137 BARIUM, DIS- SOLVED (UG/L AS BA) 30 32 32 28 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.4 8.2 7.6 7.5 SODIUM, DIS- SOLVED (MG/L AS NA) 6.7 10 8.2 6.2 NITRO- GEN, NO2+N03 DIS- SOLVED (MG/L AS N) 1.30 0.330 0.890 0.940 BERYL- LIUM, DIS- SOLVED (UG/L AS BE) -- -- -- -- TEMPER- ATURE WATER (DBG C) 22.0 25.0 25.0 25.0 SODIUM AD- SORP- TION RATIO 0.3 0.4 0.4 0.3 NITRO- GEN, AMMONIA DIS- SOLVED (MG/L AS N) 0.050 0.010 0.060 0.060 CADMIUM DIS- SOLVED (UG/L AS CD) -- -- -- -- TUR- BID- ITY (NTU) 780 3.5 65 190 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 2.1 1.5 2.1 1.8 NITRO- GEN, AMMONIA DIS- SOLVED (MG/L AS NH4) 0.06 0.01 0.08 0.08 CHRO- MIUM, DIS- SOLVED (UG/L AS CR) -- -- -- -- OXYGEN, DIS- SOLVED (MG/L) 8.4 8.8 10.0 7.2 ALKA- LINITY WAT WH TOT FBT FIELD MG/L AS CAC03 70 110 110 — NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 1.3 <0.20 0.50 1.0 COBALT, DIS- SOLVED (UG/L AS CO) <3 <2 <3 <3 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 92 95 119 88 SULFATB DIS- SOLVED (MG/L AS S04) 9.1 11 7.8 10 PHOS- PHORUS TOTAL (MG/L AS P) 0.470 0.040 0.140 0.270 COPPER, DIS- SOLVED (UG/L AS CU) -- -- -- -- COLI- FORM, FECAL, 0.7 UM-MF (COLS./ 100 ML) 33000 K680 5400 4100 CHLO- RIDE, DIS- SOLVED (MG/L AS CL) 6.1 9.5 11 6.6 PHOS- PHORUS DIS- SOLVED (MG/L AS P) 0.040 0.040 0.060 tO.010 IRON, DIS- SOLVED (UG/L AS FB) 100 12 87 150 STREP- TOCOCCI FECAL, KF AGAR (COLS. PER 100 ML) 30000 440 5700 3000 FLUO- RIDB, DIS- SOLVED (MG/L AS F) tO.10 0.20 0.20 <0.10 PHOS- PHORUS ORTHO, DIS- SOLVED (MG/L AS P) 0.030 0.030 0.050 0.030 LEAD, DIS- SOLVED (UG/L AS PB) -- -- -- -- HARD- NESS TOTAL (MG/L AS CACO3) 74 110 72 81 SILICA, DIS- SOLVED (MG/L AS SI02) 22 30 18 21 PHOS- PHATE, ORTHO, DIS- SOLVED (MG/L AS P04) 0.09 0.09 0.15 0.09 LITHIUM DIS- SOLVED (UG/L AS LI) <4 <4 <4 <4 RIO GRANDB DB ANASCO BASIN 437 50144000 RIO GRANDB DB ANASCO NR SAN SEBASTIAN, P.R. (National stream- quality accounting network station) WATER- QUALITY DATA DATE OCT 1991 31... JAN 1992 29... APR 23. .. JUL 15... MANGA- NESE, DIS- SOLVED (UG/L AS MN) 3 13 14 13 MERCURY DIS- SOLVED (UG/L AS HG) -- -- -- -- MOLYB- DENUM, DIS- SOLVED (UG/L AS MO) <10 20 <10 <10 NICKEL, DIS- SOLVED (UG/L AS NI) 2 <1 3 6 SELE- NIUM, DIS- SOLVED (UG/L AS SB) 1 <1 <1 <! SILVER, DIS- SOLVED (UG/L AS AG) <1.0 <1.0 <1.0 <1.0 STRON- TIUM, DIS- SOLVED (UG/L AS SR) 98 140 110 94 VANA- DIUM, DIS- SOLVED (UG/L AS V) <6 <6 <6 <6 ZINC, DIS- SOLVED (UG/L AS ZN) — — — — SEDI- MENT, SUS- PENDED (MG/L) -- -- -- __ SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) — — — — PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT DATE OCT 1991 31. .. JAN 1992 29. .. APR 23. .. JUL 15. .. TIME 0950 1035 1020 1005 STREAM- FLOW, INSTAN- TANEOUS (CFS) 351 73 107 420 SEDI- MENT, SUS- PENDED (MG/L) 1150 37.8 43 369 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 1089 7.5 12.4 418 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 99 95 88 47 4 38 RIO ORANDB DB ANASCO BASIN 50146000 RIO ORANDB DB ANASCO NEAR ANASCO, PR WATER- QUALITY RECORDS LOCATION. --La t 18°16'00-, long 67008'05-, at bridge on Highway 430, 0.2 mi (0.3 km) aouth of Highway 109 at Bl Bapino and 1.4 mi (2.3 km) eaat-aoutheaat from Afiaaco plaxa. DRAINAGE ARBA.--139 coaat. (360 km1 ) thia doea not include 39.7 Mi' (102.8 ka>)/ Clow ia diverted to aouth PERIOD OF RECORD. --Water yeara 1979 to current year. WATER- QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE NOV 1991 08... DEC 18... FBB 1992 19... APR 08... JUL 07. .. SBP 02. .. TIME 0715 0800 0855 0905 0845 0930 DIS- CHARGE, INST. CUBIC FEET PER SECOND 235 129 74 69 110 350 SPE- CIFIC CON- DUCT- ANCE (OS/CM) 252 258 268 258 230 150 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.8 7.8 7.5 7.0 6.9 6.8 TEMPER- ATURE WATER (DBO C) 24.5 23.5 23.5 24.5 28.0 25.0 TUR- BID- ITY (NTU) 9.1 6.0 2.5 20 8.0 250 OXYGEN, DIS- SOLVED (MG/L) 7.4 7.0 7.2 7.3 6.6 5.4 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 82 74 79 86 54 61 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) <10 11 <10 10 <10 29 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 400 270 230 K740 K130 37000 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 530 K180 K150 270 480 58000 DATE NOV 1991 08... DEC18... FEB 1992 19.. . APR08... JUL07... SBP02... HARD- NESS CALCIUM TOTAL DIS- (MG/L SOLVED AS (MG/L MAGNE- SIUM, DIS- SODIUM, DIS- SOLVED SOLVED (MG/L (MG/L CACO3) AS CA) AS MG) AS NA) 110 28 110 28 63 17 9.4 11 9.3 10 4.9 6.4 SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY SIUM, WAT WH DIS- TOT FET SULPIDE SOLVED FIELD TOTAL (MG/L MG/L AS (MG/L AS K) 0.5 1.7 0.4 2.4 0.4 2.8 CACO3 100 100 100 100 95 70 CHLO- SULFATB RIDE, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS S) AS 804) AS CL) <0.5 12 10 <0.5 17 15 8.5 6.2 NOV 08 DEC 18 FEB 19 APR 08 JUL 07 SBP 02 K = FLUO- RIDB, DIS- SOLVED DATE (MG/L AS F) 1991 <0.10 1992 0.20 <0.10 non-ideal count SILICA, DIS- SOLVED (MG/L AS SI02) 32 -- -- 31 — 18 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 164 -- -- 173 -- 99 SOLIDS, DIS- SOLVE! (TONS PER DAY) 104 — — 32.3 — 93.5 SOLIDS, RESIDUE TOTAL NITRO- NITRO- NITRO- NITRO- AT 105 GEN, GEN, GEN, GEN, SOLVED DBG. C, NITRATE NITRITE NO2+NO3 SUS- TOTAL TOTAL TOTAL PENDED (MG/L (MG/L (MG/L (MG/L (MG/L) AS N) AS N) AS N) AS N) NITRO- GEN, AMMONIA ORGANIC TOTAL TOTAL (MG/L AS N) 167 2 11 50 28 540 -- 0.510 -- 0.470 0.380 0.890 <0.010 0.010 <0.010 0.030 0.010 0.060 0.790 0.520 0.140 0.500 0.390 0.950 0.020 0.020 0.020 0.080 0.040 0.100 0.40 RIO GRANDB DB ANASCO BASIN 50146000 RIO GRANDB DB ANASCO NEAR ANASCO, PR—Continued WATBR-QDALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 439 DATS MOV 1991 08... DEC 18... PBB 1992 19.. . APR 08... JUL 07... SEP 02... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) NITRO- GEN, TOTAL (MG/L AS N) NITRO- GEN, TOTAL (MG/L AS N03) PHOS- PHORUS TOTAL (MG/L AS P) ARSENIC TOTAL (UG/L AS AS) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) BORON, TOTAL RECOV- ERABLE (UG/L AS B) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) COPPER, TOTAL RECOV- ERABLE (UG/L AS CO) <0.20 <0.20 <0.20 <0.20 <0.20 0.50 1.5 6.4 0.040 0.050 0.040 0.020 0.030 0.100 <1 <100 <100 40 20 <1 <1 <1 <1 60 DATE NOV 1991 08... DBC 18.. . FBB 1992 19.. . APR 08.. . JUL 07... SBP 02... IRON, TOTAL RECOV- ERABLE (UG/L AS FB) LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) MANGA- NESE, TOTAL RECOV- ERABLE (OG/L AS MN) MERCURY TOTAL RECOV- ERABLE (UO/L AS HG) SELE- NIUM, TOTAL (UG/L AS SB) SILVER, TOTAL RECOV- ERABLE (UO/L AS AO) ZINC, TOTAL RECOV- ERABLE (UO/L AS ZN) CYANIDE TOTAL (MG/L AS CN) PHENOLS TOTAL (UG/L) MBTHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 650 1500 <1 70 170 <0.10 <0.10 <1 <1 <1 <1 20 10 •cO.010 <0.010 <1 0.02 0.02 DATS JUL 1992 07... TIME 0845 PCS, TOTAL (UG/L) PESTICIDE ANALYSES ALDRIN, TOTAL (UG/L) <0.1 tO.010 CHLOR- DANB, TOTAL (UG/L) DDD, TOTAL (UG/L) DDE, TOTAL (UG/L) DOT, TOTAL (UG/L) <0.010 <0.010 <0.010 DI- AZINON, TOTAL (UG/L) DI- ENDO- BLDRIN 8ULPAN, TOTAL TOTAL (UG/L) (UG/L) <0.01 <0.010 <0.010 DATE JUL 1992 07.. . ENDRIN WATER HBPTA- UNPLTRD BTHION, CHLOR, RBC TOTAL TOTAL (UG/L) (UG/L) (UG/L) HBPTA- CHLOR BPOXIDB LINDANB TOTAL (UG/L) TOTAL (UG/L) •eO.010 <0.01 <0.010 <0.010 <0.010 MALA- THION, TOTAL (UG/L) <0.01 MBTH- OXY- CHLOR, TOTAL (UG/L) <0.01 METHYL PARA- THION, TOTAL (UG/L) <0.01 MIRBX, TOTAL (UG/L) <0.01 DATE JUL 1992 07.. . PARA- THION, TOTAL (UG/L) <0.01 NAPH- THA- LENES, POLY- CHLOR. TOTAL (UG/L) <0.10 PBR- TOX- THANB APHENB, TOTAL TOTAL (UG/L) (UG/L) <1 TOTAL TRI- THION (UG/L) <0.01 2,4-D, 2,4,5-T 2, 4-DP SILVBX, TOTAL TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) (UG/L) 0.09 <0.01 <0.01 <0.01 440 THIS PAGE WAS LEFT BLANK INTENTIONALLY Drainage boundary u n c e f > o i n LARFS '. EXPLANATION A H78 SURFACE-WATER STATION AND NUMBER V1476 QUALITY-OF-WATER STATION AND NUMBER A 83 WELL AND WELL NUMBER ^ 0123456 KILOMETERS 01234 MILES Figure 27-Rio Culebrinas basin. 442 RIO CULBBRINAS BASIN 50147600 RIO CULBBRINAS NBAR SAN SEBASTIAN, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°20'51". long 67°02'40", at bridge on Highway 423, 1.3 mi (2.1 k») south of Quebrada El Salto Bridge on Highway 111, and 2.1 Mi (3.4 km) weat of Central La Plata. DRAINAGE AREA.—58.2 &i* (150.7 km2 ). PERIOD OF RECORD.—Water year* 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE NOV 1991 08... DEC 18.. . PBB 1992 19... APR 07.. . JUL 08.. . AUG 27... DATE NOV 1991 08.. . DEC 18.. . FEE 1992 19... APR 07.. . JUL 08.. . AOG 27.. . DATE NOV 1991 08.. . DEC 18... FEE 1992 19... APR 07.. . JUL 08... AUG 27... TIME 1145 1240 1415 1205 1030 1100 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 20000 240 700 560 630 K13000 CHLO- RIDE, DIS- SOLVED (MG/L AS CL) 11 -- -- 17 -- 9.5 DIS- CHARGE, INST. CUBIC FEET PER SECOND 123 44 18 36 66 250 HARD- NESS TOTAL (MG/L AS CACO3 ) 130 — — 120 — 140 FLUO- RIDE, DIS- SOLVED (MG/L AS F) 0.10 — -- 0.10 -- 0.10 SPE- CIFIC CON- DUCT- ANCE (US/CM) 270 280 289 325 276 315 CALCIUM DIS- SOLVED (MG/L AS CA) 42 -- -- 40 -- 48 SILICA, DIS- SOLVED (MG/L AS SIO2) 21 -- -- 34 -- 16 PH WATER WHOLE FIELD (STAND- ARD UNITS) •f' 7.9 8.2 7.2 7.6 7.6 7.4 MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) 4.9 -- — 5.4 — 4.7 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 190 -- — 204 — 185 TEMPER- ATURE WATER (DBG C) 25.0 24.0 26.0 25.0 26.5 25.0 SODIUM, DIS- SOLVED (MG/L AS NA) 8.6 -- -- 16 -- 7.9 SOLIDS, DIS- SOLVED (TONS PER DAY) 19.8 -- — 125 — 63 TUR- OXYGEN, BID- ITY (NTU) 36 6.1 5.6 6.5 8.4 110 SODIUM AD- SORP- TION RATIO 0.2 -- -- 0.6 -- 0.3 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 46 1 10 13 14 138 DIS- SOLVED (MG/L) 8.0 9.6 9.6 8.2 8.3 7.4 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 2.9 -- -- 4.1 -- 2.4 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 78 116 107 97 91 69 ALKA- LINITY WAT WH TOT FET FIELD MG/L AS CAC03 110 100 100 110 110 140 NITRO- NITRO- GEN, GEN, NITRATE NITRITE TOTAL (MG/L AS N) 1.17 1.47 1.28 1.42 1.16 — TOTAL (MG/L AS N) 0.030 0.030 0.020 0.080 0.040 <0.010 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) <10 <10 <10 <10 <10 11 SULFIDB TOTAL (MG/L AS S) <0.5 -- -- <0.5 -- "" NITRO- GEN, N02+NO3 TOTAL (MG/L AS N) 1.20 1.50 1.30 1.50 1.20 0.980 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 24000 430 K70 440 2500 20000 SULFATB DIS- SOLVED (MG/L AS SO4) 18 — — 21 -- 14 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.060 0.050 0.020 0.060 0.060 0.040 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.54 0.25 0.18 0.24 — 0.16 K = non- ideal count RIO CULBBRINAS BASIN 50147600 RIO CULBBRINAS NEAR SAN SEBASTIAN, PR—Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 443 DATE NOV 1991 08... DEC 18... FBB 1992 19... APR 07... JUL 08... AOG 27... NITRO- GEN, AM- MONIA 4 ORGANIC TOTAL (MG/L AS N) 0.60 0.30 0.20 0.30 <0.20 0.20 NITRO- GEN, TOTAL (MG/L AS N) 1.8 1.8 1.5 1.8 — 1.2 NITRO- GEN, TOTAL (MG/L AS NO3) 8.0 8.0 6.6 8.0 __ 5.2 PHOS- PHORUS TOTAL (MG/L AS P) 0.110 0.170 0.250 0.210 0.120 0.050 ARSENIC TOTAL (OG/L AS AS) 1 -- __ 1 __ -- BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 __ __ <100 __ -- BORON, TOTAL RECOV- ERABLE (UG/L AS B) 10 -- __ 40 __ -- CHRO- CADMIUM MIUM, COPPER, TOTAL TOTAL TOTAL RBCOV- RBCOV- RECOV- ERABLE BRABLB ERABLB (UG/L (UG/L (UG/L AS CD) AS CR) AS CU) <1 <1 10 __ — <1 <1 10 __ _- DATE NOV 1991 08... DEC 18... FBB 1992 19... APR 07... JUL 08... AUG 27... IRON, TOTAL RECOV- ERABLE (UG/L AS FB) LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) SELE- NIUM, TOTAL (UG/L AS SB) SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CYANIDE TOTAL (MG/L AS CN) PHENOLS TOTAL (UG/L) MBTHY- LBNB BLUB ACTIVE SUB- STANCE (MG/L) 480 510 30 50 <0.10 <0.10 10 <0.010 10 <0.010 0.02 0.04 444 RIO CULBBRINAS BASIN 50147800 RIO CULBBRINAS AT HIGHWAY 404 NEAR MOCA, PR LOCATION.--Lat 18021'42", long 67<>05'33", Hydrologic Unit 21010003, on right bank, at bridge on Highway 404, 0.3 mi (0.5 km) downstream from Quebrada Yagruma, and 2.8 mi (4.5 km) southeast of Moca. DRAINAGE AREA.--71.2 mi* (184.4 km'). WATER-DISCHARGE RECORDS PERIOD OP RECORD.—July 1967 to current year. QAQB.—Water-stage recorder. Elevation of gage is 45 ft (14 m), from topographic map. REMARKS.—Records fair except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUO SEP 1 266 297 2 261 198 3 237 179 4 189 183 5 175 166 6 167 155 7 160 286 8 438 e200 9 530 e!60 10 322 elSS 11 218 elSO 12 209 e!45 13 669 e!40 14 263 e!40 15 272 e!27 16 199 124 17 172 119 18 540 116 19 2910 113 20 658 107 21 379 107 22 257 102 23 214 97 24 190 97 25 1780 95 26 351 103 27 237 103 28 445 104 29 272 100 30 218 95 31 729 TOTAL 13927 4263 MEAN 449 142 MAX 2910 297 MIN 160 95 AC-PT 27620 8460 CPSM 6.31 2.00 IN. 7.28 2.23 e Estimated STATISTICS OP MONTHLY MEAN MEAN 625 354 MAX 1086 799 (WY) 1973 1982 MIN 231 108 (WY) 1968 1979 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAILY MEAN LOWEST DAILY MEAN ANNUAL SEVEN-DAY MINIMUM INSTANTANEOUS PEAK PLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW PLOW ANNUAL RUNOPP (AC-PT) ANNUAL RUNOPP (CPSM) ANNUAL RUNOPP (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 92 89 86 87 85 84 81 81 78 76 76 75 71 71 71 73 82 71 67 68 76 67 65 62 61 59 58 56 55 55 56 2234 72.1 92 55 4430 1.01 1.17 79 81 61 57 89 208 99 80 75 71 72 74 71 68 65 69 60 57 56 55 56 57 56 54 54 55 54 50 49 47 45 2124 68.5 208 45 4210 .96 1.11 DATA POR WATER 145 424 1982 72.1 1992 POR 77.1 151 1971 51.2 1979 46 e43 e42 e40 41 42 44 42 40 40 41 39 38 39 38 37 36 34 34 33 32 31 32 31 31 31 31 33 31 —— 1072 37.0 46 31 2130 .52 .56 YEARS 1967 69.8 243 1981 37.0 1992 29 28 28 29 29 28 27 33 31 27 28 36 42 29 30 28 30 34 32 28 27 29 25 26 27 62 45 104 175 442 260 1828 59.0 442 25 3630 .83 .96 - 1992 65.9 319 1981 30.4 1979 1991 CALENDAR YEAR 89250 245 5060 27 29 177000 3. 46. 490 113 38 May 17 Apr 1 Mar 15 43 63 116 92 61 52 44 39 40 42 297 341 473 184 117 124 100 86 e400 e!70 e820 e350 elSO e220 ellO 92 85 78 74 72 68 68 —— 4995 166 820 39 9910 2.34 2.61 66 65 65 61 59 99 84 62 59 65 93 276 189 173 216 139 152 103 625 304 165 165 3090 686 426 409 323 1350 e600 e350 ellOO 11619 375 3090 59 23050 5.26 6.07 e700 e480 e300 e220 e200 «350 e800 elSOO eSOO e!600 e600 e400 e200 e600 e480 e350 e300 e350 323 248 216 198 182 249 187 160 151 143 139 135 —— 12561 419 1800 135 24910 5.88 6.56 129 124 133 e258 e270 e250 e!90 e!60 e!70 elSO e!90 e230 e!70 e620 ellOO e220 elSO e270 elSO e680 e220 e!70 e!60 e330 e330 e!60 elSO e240 e!90 e!40 139 7933 256 1100 124 15740 3.59 4.14 688 357 174 135 130 153 191 155 128 144 108 96 107 1080 238 184 e!53 e!60 e!40 el90 e680 e600 e300 e270 e640 e!400 744 360 286 250 232 10473 338 1400 96 20770 4.74 5.47 240 236 187 171 163 181 179 e2700 e940 e!900 eSOO e450 e560 e860 e410 e520 e390 e460 e420 e620 e410 e270 e680 e400 e470 e300 e250 e600 eSOO e2700 19267 642 2700 163 38220 9.02 10.07 , BY WATER YEAR (WY) 135 621 1986 26.4 1970 POR 1992 92296 252 3090 25 28 16600 24 24 183100 3 48 600 141 36 471 2054 1986 96.7 1973 WATER YEAR May 23 Mar 23 Mar 19 Oct 19 .75 Oct 19 Mar 23 .54 .22 389 769 1984 82.7 1974 321 847 1979 91.8 1983 WATER 295 457 179 13300 19 20 69000 36 16 213900 4 56 600 138 42 344 831 1979 119 1970 YEARS 1967 Oct Apr Apr Sep .60 Sep Apr .15 .34 520 1350 1978 145 1986 - 1992 1986 1977 21 1972 16 1979 13 1979 16 1975 16 1975 17 1979 RIO COLBBRINAS BASIN 445 50149100 RIO COLBBRINAS NEAR AGO ADA, PR NATER-QUALITY RECORDS LOCATION.--Lat 18°24'03", long 67°09'40", at bridge on Highway 2, and 2.3 mi (3.7 k») northeast of Aguada plaza. DRAINAGE AREA.--97.0 mi* (251.2 k»* ) . PERIOD OF RECORD.--Water years 1958, 1970 to current year. HATER-QUALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE NOV 1991 08. .. DEC 18... FBB 1992 19. .. APR 08... JUL 07... SEP 02... TIME 0930 1045 1145 1100 0945 1045 DIS- CHARGE, INST. COBIC FEET PER SECOND 438 110 47 50 150 250 SPE- CIFIC CON- DUCT- ANCE (OS/CM) 263 304 330 312 320 326 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.6 8.0 7.7 7.3 7.1 6.6 TEMPER- ATURE HATER (DBG C) 24.5 23.5 24.5 27.0 26.5 27.0 TUR- BID- ITY (NTU) 270 4.7 4.6 9.7 29 9.3 OXYGEN, DIS- SOLVED (MG/L) 5.4 4.8 6.3 7.2 6.6 3.6 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 70 62 79 86 82 46 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 62 13 <10 16 11 18 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K86000 K140 K60 K2000 250 29000 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 55000 K110 K60 920 730 76000 DATE NOV 1991 08... DEC 18.. . FBB 1992 19.. . APR 08... JUL 07... SBP 02.. . HARD- NESS CALCIUM TOTAL DIS- (MG/L SOLVED AS (MG/L MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L 120 38 130 44 130 45 SODIUM AD- SORP- TION RATIO CAC03) AS CA) AS MG) AS NA) 5.8 14 5.4 11 ALKA- POTAS- LINITY CHLO- SIUM, WAT WH SULFATB RIDE, DIS- TOT FBT SULFIDB DIS- DIS- SOLVED FIELD TOTAL SOLVED SOLVED (MG/L MG/L AS (MG/L (MG/L (MG/L AS K) 5.4 8.5 0.3 2.6 0.5 2.9 0.4 2.4 CAC03 140 120 130 130 130 130 AS S) AS 304) AS CL) <0.5 11 <0.5 17 14 11 15 15 NOV 08 DEC 18 FBB 19 APR 08 JUL 07 SBP 02 K = FLUO- RIDB, DIS- SOLVED DATB (MG/L AS F) 1991 0.10 ... 1992 ... 0.10 ... 0.10 non- ideal count SILICA, DIS- SOLVED (MG/L AS SI02) 16 -- -- 36 -- 26 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 177 -- -- 213 -- 203 RESIDUE SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, SOLVED DBG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL PER PBNDBD (MG/L (MG/L (MG/L (MG/L (MG/L DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) 209 28.8 137 21 1 11 21 38 192 0.620 — — 0.750 0.800 0.840 0.050 <0.010 <0.010 0.040 0.030 0.020 0.670 0.890 0.590 0.790 0.830 0.860 0.090 0.040 0.030 0.100 0.070 0.080 1.0 0.16 0.17 0.20 0.13 0.42 446 RIO CULEBRINAS BASIN 50149100 RIO CULBBRINAS NEAR AGOADA, PR--Continu«d WATER-QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DATE NOV 1991 08... DEC 18... FBB 1992 19... APR 08... JUL 07... SEP 02... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) NITRO- GEN, TOTAL (MG/L AS N) NITRO- GEN, TOTAL (MG/L AS NO3) PHOS- PHORUS TOTAL (MG/L AS P) ARSENIC TOTAL (UG/L AS AS) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) BORON, TOTAL RECOV- ERABLE (UG/L AS B) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) COPPER, TOTAL RECOV- ERABLE (UG/L AS CO) 1.1 0.20 0.20 0.30 0.20 0.50 1.8 1.1 0.79 1.1 1.0 1.4 7.8 4.8 3.5 4.8 4.6 6.0 0.130 0.090 0.080 0.080 0.050 0.080 200 <100 40 30 10 <1 29 <1 100 DATE NOV 1991 08... DEC 18.. . FBB 1992 19... APR 08... JUL 07... SEP 02... IRON, TOTAL RECOV- ERABLE (DG/L AS FB) LEAD, TOTAL RECOV- ERABLE (OG/L AS PB) MANGA- NESE, TOTAL RECOV- ERABLE (DG/L AS MN) MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) SELE- NIUM, TOTAL (UG/L AS SB) SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CYANIDE TOTAL (MG/L AS CN) PHENOLS TOTAL (OG/L) MBTHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 18000 570 18 <1 660 30 0.10 <0.10 <1 <1 <1 <1 120 <0.010 <0.010 0.01 0.03 DATE JUL 1992 07.. . TIME 0945 PCB, TOTAL (UG/L) PESTICIDE ANALYSES ALDRIN, TOTAL (DG/L) <0.010 CHLOR- DANE, TOTAL (UG/L) DDD, TOTAL (UG/L) DDE, TOTAL (UG/L) DDT, TOTAL (UG/L) DI- BNDO- BLDRIN SULFAN, TOTAL TOTAL (UG/L) (UG/L) <0.010 <0.010 <0.010 <0.010 <0.010 ENDRIN HEPTA- WATBR HBPTA- CHLOR UNFLTRD ETHION, CHLOR, BPOXIDB LINDANB DATE RBC TOTAL TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) JUL 1992 07... <0.010 <0.01 <0.010 <0.010 <0.010 MALA- THION, TOTAL (UG/L) <0.01 METH- OXY- CHLOR, TOTAL (UG/L) <0.01 METHYL PARA- THION, TOTAL (UG/L) <0.01 MIREX, TOTAL (UG/L) <0.01 DATE JUL 1992 07... PARA- THION, TOTAL (UG/L) <0.01 NAPH- THA- LENES, POLY- CHLOR. TOTAL (OG/L) <0.10 PER- TOX- THANE APHENB, TOTAL TOTAL (OG/L) (DG/L) <1 TOTAL TRI- THION (DG/L) <0.01 2,4-D, TOTAL (OG/L) 0.12 2,4,5-T 2, 4-DP SILVBX, TOTAL TOTAL TOTAL (DG/L) (OG/L) (OG/L) <0.01 <0.01 <0.01 COLBBRA, PR 50214500 QUBBRADA RBSACA NEAR MONTE RBSACA, CULEBRA, PR 447 LOCATION.--Lat 18°19'11-, long 65°18'10", Hydrologic Unit 21010006, on right bank, 1.0 mi (1.6 km)/ north of Culebra City Hall, 0.9 mi (1.4 km) southwest of Monte Resaca, and 1.0 mi (1.6 km) east of Bahia Tamarindo. DRAINAGE AREA.--0.23 mi* (0.60 km'). WATER-STAGE RECORDS PERIOD OF RECORD.--October 1991 to September 1992 (gage-height only). GAGE.--Water-stage recorder. Elevation of gage is 66 ft (20 m), from topographic map. REMARKS.--Gage-height and precipitation satellite telemetry at station. All gage-heights of 5.30 ft or lower are considered zero flow. EXTREMES FOR CURRENT YEAR.--Maximum gage-height 7.49 ft (2.283 m), May 26; minimum, 4.78 ft (1.457 m), June 8,13,15. GAGE HEIGHT, FEET, DAY OCT WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES NOV DEC JAN FBB MAR APR MAY JUN JUL ADO SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN MAX MIN 5.30 5.39 5.29 5.18 5.08 5.03 .95 .91 .91 .91 .91 .92 .91 .91 .91 .94 .92 .91 .91 .91 .91 .91 .90 .91 4 — _ _ 4 .91 .90 .90 .90 .91 1.91 5.06 5.19 5.06 5.17 .94 .91 .91 .91 .90 .98 .90 .90 .90 .90 .93 .92 .90 .98 .90 .90 .90 .90 .95 .90 1.94 4 > . 19 ! 1.90 4 .90 .99 < .07 4 .92 .97 .90 .90 .90 .90 .89 .88 .89 ! .89 .89 .90 .94 ! .95 .91 .90 .98 .90 .94 .93 .92 .91 .90 .90 .91 .91 .91 .91 1.92 ! i . 07 ! 1.88 4 1.91 1.92 1.92 1.92 5.15 5.72 5.40 5.21 5.32 5.72 5.58 5.46 5.45 5.41 5.37 5.31 5.20 .96 .91 .92 .92 .91 .91 .91 .92 .91 .91 .91 .91 .91 .91 5.12 4 i.72 ! 1.91 4 .91 .91 .91 .10 .91 .92 .90 .90 .90 .91 .91 .91 .91 .91 .91 .91 .91 .91 .91 .90 .90 .90 .90 .90 .90 .90 .90 .89 .89 --- 1.91 5.10 1.89 .90 .89 .89 .89 .88 .88 .88 .88 .88 .88 .88 .87 .88 .89 .88 .89 .88 .89 .89 .89 .89 .89 .89 .89 .89 .89 .89 .88 .88 ! .87 4 .88 .88 4 .90 ! .87 4 .88 .88 .88 .88 .88 .88 .88 .89 .89 .89 .89 .89 .89 .89 .89 .90 .89 .89 .89 .89 .89 .89 .89 ! .89 ! .89 .89 ! .89 ! .88 ! 5.01 ! 1.90 4 --- 4 1.89 4 i.Ol ! 1.88 4 .89 .89 .89 .89 .89 .89 .89 .89 .90 .89 .90 .90 .90 .90 .89 .89 .89 .89 .88 .88 .88 .88 5.11 5.64 5.51 5.67 5.30 >.15 5.01 1.89 1.84 1.99 5.67 1.84 .83 .83 .82 .82 .81 .81 .80 .80 .80 .81 .80 .80 .79 .79 .79 .80 .81 .80 .80 .81 .80 .80 .79 .80 .80 .81 .81 .81 .81 .81 --- .81 .83 .79 .81 .81 .82 .82 .82 .82 .82 .82 .82 .82 .82 .82 .82 .82 .81 .80 .80 .80 .80 .80 .81 .83 .81 .81 .81 .81 .81 .81 .81 .82 .82 .81 .83 .80 .82 .82 .82 .83 .84 .83 .83 .83 .83 .83 .83 .83 .83 .82 .82 .82 .82 .82 .82 .82 .82 .82 .82 .82 .82 .82 .81 .81 .82 .81 .81 .82 .84 .81 .81 .82 .81 .81 .81 .81 .81 .81 .84 .82 .82 .84 .83 .83 .84 .83 .83 .81 .83 .82 .82 .83 .82 .83 .82 .82 .83 .82 .82 .82 --- .82 .84 .81 448 COLBBRA, PR 50215000 DRAINAGE CANAL AT COLBBRA AIRPORT, CULBBRA, PR LOCATION.--Lat 18°19'06", long 65°18'32", Hydrologic Unit 21010006, on right bank, 0.5 mi (0.8 km), northwest of Culebra City Hall, 0.9 mi (1.4 km) northwest of desalination plant, 0.3 mi (0.5 km) northeast of Playa Sardinas I, and of Highway 251 at airport south perimeter fence. DRAINAGE AREA.--0.08 mi' (0.20 km1 ). HATER-STAGE RECORDS PERIOD OP RECORD.--October 1991 to September 1992 (gage-height only). GAGE.—Water-stage recorder. Elevation of gage is 66 ft (22 m), from topographic map. REMARKS.--Gage-height and precipitation satellite tel« considered zero flow. stry at station. All gage-heights of 10.25 ft or lower are EXTREMES POR CURRENT YEAR.—Maximum gage-height recorded, 10.27 ft (3.130 m), Nov. 16, during period of no gage-height record Jan. 5,6; minimum, 9.73 ft (2.966 m), March 6. GAGE HEIGHT, FEET, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES but nay nave been higher DAY OCT NOV JAN PBB MAR MAY JUN JUL AUO 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN MAX MIN 10.24 10.23 10.23 10.23 10.23 10.23 10.23 10.23 10.23 10.23 10.21 10.19 10.21 10.22 10.23 10.23 10.23 10.23 10.23 10.23 10.23 10.23 __- ___ __- 10.22 10.20 10.21 10.21 10.21 10.23 10.24 10.24 10.24 10.24 10.23 10.24 10.23 10.23 10.21 10.23 10.23 10.22 10.22 10.19 10.21 10.22 10.21 10.21 10.21 10.22 10.22 10.19 10.20 10.21 --- 10.22 10.24 10.19 10.20 10.21 10.20 10.19 10.20 10.18 10.16 10.20 10.19 10.18 10.17 10.16 10.15 __- --- ___ __- ___ --- ___ ___ ___ ___ --- ___ ___ ___ ___ ___ --- ___ ___ ___ SEP — ___ ___ ___ ___ ___ --- ___ ___ ___ 10.16 10.16 10.15 10.15 10.12 10.10 10.10 10.10 10.10 10.11 10.13 10.15 10.13 10.12 10.12 10.12 10.11 ___ ___ 10.11 10.12 10.14 10.16 10.16 10.16 10.17 10.17 10.16 10.16 10.14 10.12 10.11 10.11 10.11 10.12 10.11 10.11 10.13 10.12 10.12 10.13 10.12 10.11 10.10 10.10 10.09 10.09 10.09 ___ —— 10.13 10.17 10.09 10.12 10.12 10.15 10.12 ___ ___ 10.13 10.13 10.13 10.13 10.13 10.13 10.14 10.14 10.14 10.15 10.16 10.18 10.18 10.18 10.19 10.20 10.20 10.20 10.20 10.14 10.08 10.08 10.07 10.07 _-_ ___ ___ 10.08 10.08 10.08 10.09 10.08 10.07 10.07 ___ 10.02 10.02 10.02 10.02 10.02 10.02 10.02 10.02 10.02 10.02 10.03 10.04 10.05 10.04 10.05 10.05 10.05 10.05 10.05 10.05 10.05 10.05 --- ___ ___ ___ 10.05 10.05 10.02 10.03 10.03 10.03 10.03 10.03 10.03 10.04 10.04 10.04 10.04 10.04 10.04 10.04 10.04 10.05 10.04 10.04 10.04 10.05 10.05 10.04 10.04 10.05 10.03 10.07 10.02 10.02 __- __- 10.02 10.02 10.01 10.02 10.02 10.02 10.02 10.04 10.04 10.07 10.09 10.05 10.04 10.04 10.07 10.06 10.05 10.05 10.05 10.06 10.08 10.03 10.04 10.04 10.04 10.05 10.05 10.06 10.06 10.06 --- 10.04 10.09 10.01 10.06 10.06 10.06 10.06 10.05 ___ 10.23 10.25 10.24 --- 10.22 10.22 10.24 10.25 10.25 10.25 10.25 10.25 10.25 10.25 10.25 10.25 10.25 10.25 10.25 10.25 10.25 10.25 10.25 10.25 10.25 __- ___ 10.25 10.25 10.25 10.25 10.25 10.25 10.25 10.25 10.25 10.25 10.25 10.25 ___ ___ --- -__ ___ ___ ___ --- ___ ___ ___ ___ ___ ___ ___ ___ ___ __- ___ —— __- --- ___ ___ ___ 10.25 10.25 10.25 10.25 10.25 10.25 10.25 10.25 10.25 10.25 10.25 10.25 10.25 10.25 10.25 10.25 10.25 10.25 10.25 10.25 10.25 10.25 --- --- VIEQUBS, PR 449 50231000 QOEBRADA COFRESI TROBOTARY NEAR ISABEL SBGUNDA, VIBQUBS, PR LOCATION.—Lat 18°08'21", long 65°26'06", Hydrologic Unit 21010006, on right bank, 1.0 mi (1.6 km), south- southwest of Isabel Segunda Plaza, 0.5 mi (0.8 km) north of Destine school,and 1.5 mi (2.4 km) southeast of junction of Highways 200 and 201. DRAINAGE AREA.--0.28 mi a (0.72 km»). HATER-STAGE RECORDS PERIOD OF RECORD.—July 1991 to current year (gage-height only). GAGE.—Water-stage recorder. Elevation of gage is 196 ft (60 m), from topographic map. REMARKS.—Gage-height and precipitation satellite telemetry at station. All gage-heights of 8.20 ft or lower are considered zero flow. EXTREMES FOR CURRENT PERIOD.--JULY TO SEPTEMBER 1991i Maximum gage-height, 9.75 ft (2.972 m), Aug. 27; minimum, 7.95 ft (2.423 m), Aug. 19, 20. MATER YEAR 19921 Maximum gage-height, 10.51 ft (3.20 m), Jan. 5, 1992; minimum, 7.69 ft (2.344 •), Aug. 28. GAGE HEIGHT, FEET, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN MAX MIN 8.56 8.54 8.54 8.54 8.52 --- ___ 8.50 8.49 8.49 8.46 8.45 8.47 8.48 8.44 8.40 8.36 8.32 8.27 8.23 8.20 8.16 8.14 8.11 8.08 8.04 8.16 8.61 8.64 8.59 *.56 8.57 8.57 8.77 8.74 8.71 8.67 8.65 8.43 8.77 8.04 8.64 8.66 8.64 8.63 8.62 8.63 8.65 8.63 8.67 8.66 8.63 8.60 8.59 8.56 8.55 8.54 8.53 8.53 8.53 8.53 8.53 —— —— __- —— ___ 450 DAY 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN MAX KEN VIEQOBS, PR 50231000 QUEBRADA COFRBSI TRUBUTARY NEAR ISABEL SEGONDA, VIBQDBS, PR-Continued GAGE HEIGHT, FEET, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES OCT 8.55 8.49 8.47 8.44 8.44 8.43 8.43 8.43 8.41 8.41 8.38 8.31 8.30 NOV DEC JAN FEB MAR APR MAY JDN JUL AOG SEP _-_ —— —— 8.50 8.60 8.61 8.56 8.56 8.58 8.56 8.54 8.54 8.54 8.53 8.53 8.56 8.52 8.55 8.52 8.51 8.56 8.51 8.51 8.50 8.48 8.47 8.47 8.48 8.60 8.53 8.49 8.47 8.50 8.51 8.48 8.45 8.45 8.46 8.46 8.45 8.42 8.42 8.40 8.52 8.49 8.60 8.40 8.49 8.47 8.44 8.43 8.64 8.87 8.72 8.70 8.73 8.73 8.72 8.70 ___ ___ 8.71 8.77 8.75 8.75 8.72 8.71 8.69 8.69 8.69 ___ ___ —— 8.69 8.66 8.66 8.69 8.66 8.67 8.66 8.65 8.65 8.64 8.62 8.61 8.61 8.62 8.60 8.58 8.58 8.58 8.57 8.56 8.56 8.57 8.55 8.54 8.53 8.52 8.50 8.50 8.48 —— 8.60 8.69 8.48 8.46 8.53 8.52 8.50 8.45 8.43 8.45 8.53 8.47 8.44 8.44 8.43 8.42 8.47 8.51 8.46 8.48 8.50 8.47 8.45 8.46 8.52 8.49 8.48 --- __- ___ —— _ _ ___ — - ___ 8.44 8.40 8.39 8.35 8.31 8.28 8.26 8.22 8.18 8.14 8.10 8.04 8.01 8.00 7.99 7.98 7.95 7.90 7.87 7.82 7.79 7.78 7.78 7.78 --- ___ 7.97 8.26 8.36 8.33 8.27 8.21 8.19 8.14 8.08 8.01 7.96 7.91 7.86 7.82 7.77 7.76 7.77 7.76 7.75 7.77 7.91 7.96 8.14 8.78 8.63 8.65 8.65 8.63 8.64 8.64 8.64 8.17 8.78 7.75 8.64 8.65 8.65 8.64 8.63 8.63 8.64 8.64 8.64 8.64 8.64 8.64 8.65 8.65 8.65 8.64 8.63 8.63 8.62 8.65 8.65 8.65 8.65 8.64 8.63 8.61 8.60 8.59 8.56 8.54 --- 8.63 8.65 8.54 8.52 8.50 8.47 8.45 8.40 8.36 8.31 8.25 8.22 8.17 8.15 8.31 8.36 8.33 8.28 8.22 8.39 8.56 8.54 8.52 8.54 8.59 8.57 8.55 8.50 8.43 8.34 8.28 8.20 8.12 8.05 8.37 8.59 8.05 8.01 7.96 7.93 7.86 8.19 8.51 8.50 8.51 8.51 8.50 8.43 8.34 8.26 8.23 8.47 8.50 8.47 8.44 8.36 8.29 8.20 8.11 8.02 7.97 7.91 7.83 7.77 7.71 7.71 7.71 7.71 8.16 8.51 7.71 7.71 7.71 7.71 7.72 7.72 7.72 7.92 8.48 8.50 8.51 8.53 8.51 8.51 8.55 8.49 8.56 —— ___ —— ___ —— VIBQUBS, PR 45 I 50232000 QUBBRADA LA MIMA NEAR BSPBRANZA, VIBQUBS, PR LOCATION.--Lat 18°06'54", long 65°28'15", Hydrologic Unit 21010006, on left bank 300 ft (91 m) west from state road 996, 1.4 mi (2.2 km) south of Cerro Martineau, 0.7 mi (1.1 km) east-northeast of Colonia Puerto Real on road 201 and 1.2 mi (1.9 km) north of Bsperanza. DRAINAGE AREA.--0.68 mi> (1.76 km>). WATER-STAGE RECORDS PERIOD OP RECORD.—July 1991 to current year (gage-height only). GAGE.—Water-stage recorder. Elevation of gage is 98 ft (30 m), from topographic map. REMARKS.--Gage-height and precipitation satellite telemetry at station. All gage-heights of 9.20 ft or lower are considered zero flow. EXTREMES FOR CURRENT PERIOD.--JULY TO SEPTEMBER 1991: Maximum gage-height, 9.18 ft (2.798 m), Aug. 27; minimum, 8.92 ft (2.719 m), July 24-26. WATER YEAR 1992: Maximum gage-height, 9.51 ft (2.899 m), Jan 5; minimum, 8.81 ft (2.685 m), many days. GAGE HEIGHT, FEET, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES OCT NOV DEC JAN FBB MAR APR MAY JUN JUL ADO SSP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN MAX MIN 8.93 8.93 8.94 8.93 8.94 8.94 8.94 ___ ___ ___ 8.94 8.95 8.95 8.94 8.94 8.95 8.96 8.96 8.96 8.96 8.97 8.97 8.97 8.97 8.97 8.96 8.96 8.96 8.96 8.96 8.95 8.99 8.96 8.96 8.96 8.96 9.01 8.95 8.94 8.94 8.94 8.96 9.01 8.94 8.94 8.94 8.94 8.94 8.94 8.94 8.94 8.94 8.94 8.94 8.94 8.94 8.94 8.94 8.94 8.94 8.95 8.95 8.94 8.94 8.94 8.94 8.94 8.94 8.94 8.94 8.94 8.94 8.96 8.94 8.94 8.96 8.94 452 VIBQ0BS, PR 50232000 QUBBRADA LA MINA NEAR BSPBRANZA, VIBQUBS, PR-Continued GAGB HEIGHT, FEET, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES DAY OCT NOV DEC JAN PEB MAR APR MAY JDN JOL AUO SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN MAX MIN 8.93 8.93 8.92 8.91 8.91 8.91 8.91 8.91 8.93 8.91 8.90 8.90 8.90 8.90 8.90 8.90 8.90 8.90 8.90 8.89 8.89 8.89 8.89 8.89 8.88 8.88 8.88 8.88 8.88 8.88 8.88 8.90 8.93 8.88 8.97 8.88 8.88 8.87 8.87 8.87 9.07 9.18 9.13 9.00 8.86 8.86 8.86 8.85 8.86 8.86 8.86 8.85 8.85 8.85 8.96 9.12 9.09 9.08 9.00 9.12 9.08 8.95 8.84 8.84 8.95 9.18 8.84 8.84 8.84 8.84 8.84 8.84 8.83 8.83 8.83 8.83 8.83 8.83 8.83 8.83 8.83 8.83 8.83 8.83 8.83 8.83 8.83 8.83 8.83 8.83 8.83 8.83 8.83 8.83 8.83 8.83 8.83 8.83 8.83 8.84 8.83 8.83 8.83 8.83 8.83 8.90 ___ ___ 8.87 8.83 8.87 8.82 8.82 8.81 8.82 8.82 8.82 8.82 8.82 8.82 8.82 8.82 8.82 8.82 8.82 8.82 8.82 8.82 8.82 8.82 8.82 8.82 ___ 8.82 8.82 8.82 8.82 8.82 8.82 8.82 8.82 8.82 8.82 8.82 8.82 8.82 8.82 8.82 8.82 8.82 8.82 8.82 8.82 8.83 8.85 8.85 8.85 8.85 8.85 8.83 8.83 8.83 ___ --- 8.83 8.85 8.82 8.83 8.82 8.82 8.81 8.81 8.81 8.81 8.81 8.81 8.81 8.81 8.81 8.81 8.82 8.81 8.81 8.81 8.81 8.81 8.81 8.81 8.81 8.81 8.81 8.82 8.82 8.82 8.82 8.82 8.82 8.82 8.81 8.83 8.81 8.82 8.82 8.82 8.82 8.82 8.83 8.84 8.84 8.84 8.84 8.84 8.84 8.84 8.84 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.84 --- 8.84 8.85 8.82 8.84 8.83 8.83 8.85 8.85 8.86 8.85 8.85 8.85 8.85 8.85 8.84 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.87 9.08 8.98 8.96 9.04 8.90 8.84 8.82 8.82 8.87 9.08 8.82 8.82 8.82 8.82 8.82 8.83 8.83 8.83 8.83 8.83 8.83 8.83 8.83 8.83 8.83 8.84 8.84 8.84 8.84 8.84 8.84 8.84 8.84 8.84 8.84 8.84 8.85 8.84 8.84 8.84 8.84 --- 8.83 8.85 8.82 8.84 8.84 8.84 8.84 8.84 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.84 8.85 8.85 8.85 8.85 8.90 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.90 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.85 8.86 8.86 8.86 8.85 8.85 8.85 8.85 8.88 8.92 8.92 8.90 8.90 8.90 8.90 8.90 8.90 8.90 8.90 8.87 8.92 8.85 VIEQUES, PR 453 50233000 QOBBRADA PILON AT COLONIA PUERTO REAL, VIEQUES, PR LOCATION.--Lat 18°06'37", long 65<>28'51", Hydrologic Unit 21010006, on left bank 1.2 mi (1.9 ka) southeast of Cerro Sonadora, 1.2 mi (1.9 km) northwest of Bsperanza, 0.4 mi (0.6 km) south of junction of Highways 895 and 201. DRAINAGE AREA.--0.67 mi» (1.74 km>)• WATER-STAGE RECORDS PERIOD OF RECORD.—July 1991 to current year (gage-height only). QAQB.—Water-stage recorder. Elevation of gage is 131 ft (40 m), from topographic map. REMARKS.--Oage-height and precipitation satellite telemetry at station. All gage-heights of 7.20 ft or lower are considered zero flow. EXTREMES FOR CURRENT PERIOD.--JULY TO SEPTEMBER 1991i Maximum gage-height, 7.33 ft (2.234 m), Aug. 20; minimum, 7.08 ft (2.158 m), Sept. 24-27. WATER YEAR 1992: Maximum gage-height, 7.36 ft (2.243 m), Aug. 16; minimum, 6.89 ft (2.100 m), Apr 9-13. GAGE HEIGHT, FEET, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUO SEP 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN MAX MIN 7.30 7.30 7.30 7.30 7.30 7.29 ___ ___ 7.29 7.29 7.28 7.28 7.28 7.29 7.28 7.27 7.27 7.29 7.29 7.28 7.27 7.28 7.28 7.28 7.26 7.25 7.22 7.27 7.31 7.30 7.28 7.26 7.26 7.26 7.26 7.25 7.24 7.24 7.23 7.27 7.31 7.22 7.23 7.23 7.21 7.21 7.21 7.21 7.19 7.20 7.19 7.18 7.18 7.17 7.16 7.15 7.14 7.14 7.15 7.15 7.15 7.14 7.14 7.16 7.15 7.11 7.10 7.11 7.12 7.12 7.14 7.12 7.16 7.23 7.10 454 DAY OCT VIEQOBS, PR 50233000 QUBBRADA PILON AT COLONIA PUERTO REAL, VIEQUBS, PR--Continued GAGE HEIGHT, FEET, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES NOV DEC JAN 1 2 3 4 S 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 MEAN MAX MIN 7.12 7.12 7.12 7.14 7.14 7.14 7.13 7.10 7.14 7.14 7.14 7.15 7.16 7.19 7.19 7.15 7.14 7.14 7.13 7.12 7.12 7.12 7.12 7.11 7.10 7.10 7.09 7.08 7.09 7.09 7.08 7.13 7.19 7.08 7.08 7.29 7.28 7.29 7.30 7.30 7.29 7.29 7.29 7.28 7.26 7.26 7.26 7.25 7.31 7.32 7.31 7.31 7.30 7.30 7.31 7.31 7.30 7.31 7.31 7.31 7.31 7.31 7.31 7.31 --- 7.29 7.32 7.08 7.30 7.30 7.31 7.31 7.31 7.32 7.32 7.32 7.32 7.32 7.32 7.33 7.33 7.33 7.33 7.33 7.33 7.33 7.33 7.32 7.32 7.32 7.32 7.33 7.33 7.33 7.33 7.32 7.32 7.32 7.32 7.32 7.33 7.30 7.31 7.31 7.31 7.31 7.30 7.29 7.30 7.29 7.28 7.28 7.27 7.25 7.24 7.23 7.25 7.25 7.23 7.23 7.23 7.22 7.22 7.22 7.24 7.24 7.24 7.24 7.23 7.23 7.23 ___ --- ___ ___ ___ FBB MAR APR JON JUL ADO SEP ___ --- ___ ___ ___ -— ___ ___ ___ --- ___ ___ ___ — ___ ___ ___ ___ --- 7.27 7.26 7.21 7.18 7.17 7.15 ___ ___ 7.11 7.11 7.09 7.08 7.07 7.05 7.03 7.02 7.01 6.98 6.96 6.94 6.93 6.94 6.95 6.93 7.02 7.07 7.07 7.05 7.01 6.96 6.95 6.95 6.96 6.96 6.95 6.95 6.97 7.11 7.01 7.11 6.93 7.12 7.11 7.08 7.04 7.03 7.07 7.05 7.01 6.98 6.99 6.99 7.00 7.00 7.00 7.00 7.00 7.01 7.01 7.01 7.01 7.02 7.02 7.04 7.16 7.16 7.17 7.18 7.17 7.17 7.18 7.19 7.06 7.19 6.98 ::: ___ ___ — ___ ___ ___ ___ --- ___ ___ ___ ___ --- ___ ___ 7.23 7.23 7.23 7.23 7.23 7.22 7.21 7.21 7.21 7.21 7.20 7.20 7.19 --- ___ ___ 7.17 7.15 7.13 7.12 7.08 7.05 7.02 7.04 7.03 6.98 7.10 7.04 6.98 6.96 6.96 6.95 7.17 7.15 7.13 7.05 7.01 7.16 7.12 7.13 7.14 7.03 6.98 6.97 6.96 6.96 6.96 7.05 7.17 6.95 6.96 6.96 6.96 6.96 7.22 7.16 7.19 7.15 7.06 7.06 7.21 7.19 7.16 7.28 7.31 7.28 7.18 7.15 7.16 7.16 7.16 7.16 7.16 7.16 7.16 7.16 7.15 7.15 7.16 7.15 7.16 7.14 7.31 6.96 7.15 7.16 7.16 7.16 7.16 7.16 7.16 7.16 7.16 7.16 7.16 7.16 7.16 7.07 6.95 6.95 6.96 6.95 7.02 ___ ___ ___ ___ ___ ___ 455 Discharge at Parcial-Record Stations in Puerto Rico 456 DISCHARGE AT PARTIAL-RECORD STATIONS Ac the number of streams on which streamflow information is likely to be dec!red far exceed* the number of stream-gaging station* feasible to operate at one time, the Geological Survey collects limited streamflow data at sites other than stream-gaging stations. When limited streamflow data are collected on a systematic basis over a period of years for use in hydrologic analyses, the site at which the data are collected is called a partial-record station. Data collected at these partial-record stations are useable in low-flow or floodflow analyses, depending on the type of data collected. In addition, discharge measurements are made at other sites not included in the partial- record program. These measurements are generally made in times of drought or flood to give better areal coverage to those events. Those measurements and others collected for some special reason are called measurements at miscellane- ous sites. Low-flow partial-record stations measurements of streamflow in the areas covered by this report made at low-flow partial-record stations are given in the following table. These measurements were made during periods of base flow when streamflow is pri- marily from ground-water storage. These measurements, when correlated with the simultaneous discharge of nearby stream when continuous records are available, will give a picture of the low-flow potentiality of stream. STATION NUMBER Discharge measurements made at low-flow partial-records stations during water year 1992 PUBLICATION RECORD LOCATION AND BASIN STATION NAME 50095900 Quebrada Me1anla near Jobos, PR 50097000 Quebrada Cimarrona near Jobos, PR 50097800 Rio Seco near Central Guamanl, PR 50100200 Rio Lapa near Rabo del Buey, PR 50100300 Rio Jajome at Jajome, PR 50100450 Rio Majada at La Plena, PR 50100700 Rio Majada at Rabo del Buey, PR DRAINAGE AREA mi* (km») DATE Rio Melania basin Lat 17«57'51", long 66°59'30". 2.75 1/28/92 Hydrologic unit 21010004. (7.13) 0.6 mi (1.0 km) upstream 6/19/92 from bridge on Hwy 3. Lat 17°59'18*, long 66°10'59". 3.09 1/28/92 Hydrologic unit 21010004. (8.00) Barrio Pozo Hondo, 2.4 mi 6/19/92 (3.7 km) north from Puerto de Jobos, and 4.0 mi (6.4 km) northwest from Guayama Plaza. Rio Seco basin Lat 17°58'06*, long 66°10'52". 11.2 1/28/92 Hydrologic unit 21010004. At (29.0) Bridge on Hwy 3, .2 mi (0.3 6/19/92 (0.3 km) north of Central Guamani, and 1.2 mi (1.9 km) northwest of Jobos. Rio Salinas (Nigua) basin Lat 18»03'36", long 66°14'28". 10.0 1/28/92 Hydrologic unit 21010004. (25.8) Barrio Lapa, at Hwy 1, 1.6 mi 6/04/92 (2.6 km) upstream from conflu- ence with Rio Majada, and 6.2 6/30/92 mi (10 km) southwest from Cayey Plaza. 9/29/92 Lat 18°03'49", long 66°09'38*. 4.56 1/28/92 Hydrologic unit 21010004. (11.8) Barrio Jajome Bajo, at Hwy 6/04/92 708, 3.5 mi (5.6 km) south from Cayey Plaza. 6/30/92 9/29/92 Lat 18»02'40", long 66°12'27". 16.7 1/28/92 Hydrologic unit 21010004. (43.2) Barrio Quebrada Yegua, at Hwy 6/04/92 712, 2.0 mi (3.2 km) northeast from Albergue Olimpico, and 5.5 6/30/92 mi (8.8 km) southwest fron Cayey Plaza. 9/29/92 Lat 18°02'17", long 66014'27". 22.2 1/28/92 Hydrologic unit 21010004. (57.5) Barrio Lapa, 0.2 mi (0.3 km) 6/04/92 upstream from confluence with Rio Lapa, 400 ft upstream from 6/30/92 intersection of Rwy's 1 and 712, and 0.2 mi (0.3 km) nortwest 9/29/92 from Albergue Olimpico. TIME 0715 0955 0815 0915 0745 0942 1300 0940 0730 1335 0850 1050 0820 1135 1005 1135 0910 1215 1105 1225 1000 1300 STREAM- FLOW ftV» 0.52 (0.015) 0.32 (0.009) 0.00 0.11 (0.003) 0.00 0.00 4.49 (0.127) 17.2 (0.487) 4.19 (0.119) 1.15 (0.32) 1.54 (0.044) 3.63 (0.102) 2.18 (0.062) 2.09 (0.059) 3.91 (0.111) 16.3 (0.462) 6.66 (0.189) 3.86 (0.109) 3.51 (0.099) 20.3 (0.575) 6.91 (0.196) 3.21 (0.091) STATION NUMBER STATION NAME DISCHARGE AT PARTIAL-RECORD STATIONS Low-flow partial-record stations—Continued LOCATION 504.02000 Rio Salinas at Salinas, PR 50102400 Rio Jueyes at Rio Jueyes, PR 50103000 Rio Jueyes near Jauca, PR 50104000 Rio Coamo near Pasto, PR 50105400 Rio Cuy6n at La Guava, PR 50105600 Rio Cuy6n near Coamo, PR 50105900 Quebrada Monte near Coamo, PR 50106100 Rio Coamo at Coamo, PR 50106600 Rio de La Mina near Coamo, PR 50106650 Rio del Pasto near Coamo, PR AND BASIN Lat 17°58'42", long 66°18'17". Hydrologic unit 21010004. At Bridge on Hwy 1, and 0.4 mi (0.6 km) west from Salinas Plaza. Rio Jueyes basin Lat 18°01'17", long 66°19'51". Hydrologic unit 21010004. …