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U.6. GEOLOGICAL SURVEY-U GSA CENTER 9S1 FEDERAL DRIVE stare 400-7S Water Resources Data Puerto Rico and the U.S. Virgin Islands Water Year 1993 Isla de Vieques PUERTO RICO St Thomas I St John I U. S. V I R G I N ISLANDS Saint Croix I U.S. GEOLOGICAL SURVEY WATER-DATA REPORT PR-93-1 Prepared in cooperation with the Commonwealth of Puerto Rico, the Government of the U.S. Virgin Islands and other agencies CALENDAR FOR WATER YEAR 1993 1992 S M OCTOBER T W T 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 NOVEMBER S M T W T F S 1234567 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 DECEMBER 5 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 1993 JANUARY 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 APRIL S M T W T F S 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 FEBRUARY 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 MAY S M T W T F S 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 MARCH 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 31 JUNE 5 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 JULY S M T W T F S 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 AUGUST S M T W T F S 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 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 Water Resources Data Puerto Rico and the U.S. Virgin Islands Water Year 1993 by P.L. Dfaz, Z. Aquino, C. Figueroa-Alamo, R.J. Vachier, and A.V. Sanchez St Thomas Isla de V* Culebra Isla de Vieques PUERTO RICO St John I U. S. V I R G I N ISLANDS Saint Croix I U.S. DEPARTMENT OF THE INTERIOR BRUCE BABBITT, Secretary U.S. GEOLOGICAL SURVEY Gordon P. Eaton, Director Ill 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: Jos6 M. Agis George Arroyo Angel Class-Cacho Iris M. Concepci6n Felix V. Elfas Angel G. Ferrer Eduardo Figueroa Pedro Galindo Jos6 Gonzalez Evelyn S. Guevara Senen Guzman-Rios Felipe Hernandez Richard Kessler Sandra Lagares Ernesto Mangual Carlos Narvaez Jerry A. Qrtiz Keith Overton Antonio Pagan-Gavino Rafael Pena-Cortez Francisco Perez-Blair Carlos C. Rodrfguez Julio A. Rodriguez Jos6 Ren6 Sanchez Luis Santiago-Rivera Carlos S antes Luis Soler Heriberto Torres-Sierra Jos6 A. Torres Ahmed Valencia Ruth I. Guzman typed the text of the report. Ernesto Mangual and Luis Menoyo 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. 50777-101_______________ REPORT DOCUMENTATION PAGE 1. REPORT NO. USGS/WRD/HD-94/284 J. Recipients Accession No. 4. Title end Subtitle Water Resources Data for Puerto Rico and the U.S. Virgin Islands Water Year 1993 5. Report Dft* April-1994 7. Author**) Pedro L. Dfaz, Zaida Aquino, Carlos Figueroa-Alamo, Ricardo J. Vachier, Ana V. Sanchez 8. Perfooning OrganuatUxi Rept. No. USGS-WDR-PR-93-1 9. Performing Organization Name and Atfdresa U.S. Geological Survey, Water Resources Division P.O. Box 364424 San Juan, Puerto Rico 00936-4424 10. Proiect/Tesk/Worfc Unit No. 11. Contract (C) or Grant(G) No. (C) (G) 12. Sponsoring Organization Name end Address U.S. Geological Survey, Water Resources Division P.O. Box 364424 San Juan, Puerto Rico 00936-4424 IS. Type of Report & Period Covered Annual-Oct. 1, 1992 _la Sp.pt. W, 1QQ3______ u. IS. Supplementary Notes 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 1993 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 81 streamflow-gaging stations; stage only for 12 gaging stations, daily sediment records for 21 streamflow stations; 112 partial-record or miscellaneous streamflow stations; stage records for 11 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 86 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 e. Descriptors *Surface water, *Water quality, *Ground water, Aquifers, Chemical analysis, Gaging stations, Hydrologic data, Sediments, Streamflow, Water analysis, Water Levels, Lakes. b. Identlfiers/Open-Cnded Terms Puerto Rico, U.S. Virgin Islands, Sampling sites. c. COSATI Field/Group IS. Aveilabihty Statamen; NO RESTRICTION ON DISTRIBUTIONS 19. Security Class (This Report) Unclassified 20. Security Cless (This Pege) Unclassified 21. No. of Pages 584 22. Price (See ANSI-Z39.18) &e« Initrvctiont on Reverie OPTIONAL FORM 272 (4-77) (Formerly NTIS-35) Department of Commerce CONTENTS V 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 ..................................................................... 8 Special networks and programs ............................................................. 9 Explanation of records ................................................................... 9 Station identification numbers .......................................................... 10 Downstream order system ......................................................... 10 Latitude-longitude system ......................................................... 10 Records of stage and water discharge ..................................................... 20 Data collection and computation .................................................. 20 Data Presentation ............................................................ 21 Station manuscript .......................................................... 21 Data table of daily mean values ................................................. 22 Statistics of monthly mean data ................................................. 23 Summary statistics .......................................................... 23 Identifying estimated daily discharge ................................................. 24 Accuracy of the records .......................................................... 24 Records of surface-water quality ........................................................ 25 Classification of records .......................................................... 25 Arrangement of records .......................................................... 25 On-site measurements and sample collection ............................................ 25 Water temperature .............................................................. 26 Sediment .................................................................... 26 Laboratory measurements ......................................................... 26 Data presentation ............................................................... 27 Remark codes ................................................................. 28 Records of ground-water levels ......................................................... 28 Data collection and computation .................................................... 28 Data presentation ............................................................... 29 Records of ground-water quality ........................................................ 29 Data collection and computation .................................................... 30 Data presentation ............................................................... 30 Access to WATSTORE data ............................................................... 30 Definition of terms ...................................................................... 31 Publications on Techniques of Water-Resources Investigations ....................................... 41 Surface- and quality-of-water records for Puerto Rico ............................................. 45 Discharge at partial-record stations in Puerto Rico ............................................... 427 Water-quality at partial-record stations in Puerto Rico ............................................ 441 Ground-water records for Puerto Rico ....................................................... 453 Surface-water records for the U.S. Virgin Islands ............................................... 509 Ground-water records for the U.S. Virgin Islands ............................................... 527 Index .............................................................................. 559 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 .................. 11 4. Map showing location of fecal streptococci bacteria concentration at sampled sites ................ 12 5. Map showing location of surface-water stations in Puerto Rico .............................. 13 6. Map showing location of water-quality stations in Puerto Rico .............................. 14 7. Map showing location of low-flow partial-record stations in Southwest Puerto Rico ............... 15 8. Map showing location of ground-water stations in Puerto Rico .............................. 16 9. Map showing location of surface-water stations in U.S. Virgin Islands ........................ 17 10. Map showing location of ground-water stations in the U.S. Virgin Islands ..................... 18 11. Map showing location of surface-water stations in Vieques and Culebra Islands ................. 19 12. Grid showing system for numbering wells and miscellaneous site (latitude and longitude) .......... 20 13. Map showing the Rio Guajataca basin .............................................. 47 14. Map showing the Rio Camuy basin ................................................ 55 15. Map showing the Rio Grande de Arecibo basin ........................................ 59 16. Map showing the Rio Grande de Manatf basin ......................................... 85 17. Map showing the Rio Cibuco basin ............................................... 105 18. Map showing the Rio de la Plata basin ............................................. 113 19. Map showing the Rio Hondo to the Rio Puerto Nuevo basins ............................. 147 20. Map showing the Rio Grande de Loiza basin ......................................... 191 21. Map showing northeastern river basins the Rio Herrera to the Rio Antdn Ruiz basins ............ 309 22. Map showing southeastern river basins the Rio Humacao to the Rio Seco basins ................ 327 23. Map showing south coast river basins the Rio Salinas to the Rio Jacaguas basins ............... 345 24. Map showing south coast river basins the Rio Inab6n to the Rio Loco basins .................. 367 25. Map showing the Rio Guanajibo basin ............................................. 387 26. Map showing the Rio Yagiiez and the Rio Grande de Anasco basins ........................ 403 27. Map showing the Rio Culebrinas basin ............................................. 415 TABLES Page Table 1. Island-wide monthly precipitation and annual averages for 1993 water year and the 30-year reference period, 1951-80 .............................................. 3 2. Highest water level recorded during 1993 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 3. Surface-water quality stations in Puerto Rico with highest concentration of selected constituents during water year 1993 ......................................... 8 4. Factors for conversion of chemical constituents in milligrams per liter to milli- equivalents per liter .......................................................... 35 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 Page RIO GUAJATACA BASIN Rio Guajataca at Lares (d,c,b) .......................................... 50010500 48 Canal Principal de Diversiones at Lago Guajataca (c,b) ........................ 50011000 51 Rio Guajataca above mouth near Quebradillas (c,b) ........................... 50011400 53 RIO CAMUY BASIN Rio Camuy at Tres Pueblos Sinkhole (d) ................................... 50014600 56 Rio Camuy near Bayaney (d) ........................................... 50014800 57 Rio Camuy near Hatillo (d) ............................................ 50015700 58 RIO GRANDE DE ARECEBO BASIN Lago Garzas near Adjuntas (e) ...................................... 50020100 60 Rio Grande de Arecibo near Adjuntas (c,b) ................................. 50020500 62 Rio Grande de Arecibo near Utuado (c,b) .................................. 50025000 64 Rio Saliente at Coabey near Jayuya (d) ................................ 50025155 66 Rio Caonillas above Lago Caonillas near Jayuya (c,b) ............................. 50026050 67 Lago Caonillas at Caonillas (e) ...................................... 50026140 69 Rio Grande de Arecibo below Lago Dos Bocas near Florida (c,b) ................. 50027250 70 Rio Grande de Arecibo above Arecibo (d) .................................. 50027750 72 Rio Tanama" near Utuado (d,c,b,s) .................................... 50028000 73 Rio Tanama" at Charco Hondo (d) .................................... 50028400 82 Rio Grande de Arecibo at Central Cambalache (c,b) ........................... 50029000 83 RIO GRANDE DE MANATI BASIN Rio Orocovis at Orocovis (d)........................................ 50030460 86 Rio Orocovis near Orocovis (c,b) ..................................... 50030700 87 Rio Grande de Manati near Morovis (d,c,b) ................................. 50031200 89 Lago El Guineo at Damsite (e) ...................................... 50032290 92 Lago Matrullas at Damsite (e) ....................................... 50032590 93 Rio Bauta near Orocovis (d) ........................................ 50034000 94 Rio Grande de Manati at Ciales (d) ....................................... 50035000 95 Rio Grande de Manati at Highway 149 at Ciales (c,b) .......................... 50035500 96 Rio Cialitos at Highway 649 at Ciales (c,b) ............................. 50035950 98 Rio Grande de Manati at Highway 2 near Manati (d,c,b,p) ...................... 50038100 100 LAGUNA TORTUGUERO BASIN Laguna Tortuguero Outlet near Vega Baja (c,b) .............................. 50038200 104 RIO CIBUCO BASIN Rio Cibuco below Corozal (d,c,b) ........................................ 50038320 106 Rio Cibuco at Vega Baja (d,c,b) ......................................... 50039500 109 RIO DE LA PLATA BASIN Lago Carite at Gate Tower (e) .......................................... 50039990 114 Rio de La Plata at Proyecto La Plata (d,c,b) ................................. 50043000 115 Rio de La Plata at Comerio (d).......................................... 50043800 118 VIII SURFACE-WATER AND WATER-QUALITY STATIONS, IN DOWNSTREAM ORDER, FOR WHICH RECORDS ARE PUBLISHED IN THIS VOLUME-Continued Station number Page Rfo de La Plata near Comerio (c,b) ....................................... 50044000 125 Rio Guadiana at Guadiana (d) ....................................... 50044830 127 Rio Guadiana near Naranjito (c,b) .................................... 50044850 134 Lago La Plata at Damsite (e) ........................................... 50045000 136 Rfo de La Plata below La Plata Dam (d) ................................... 50045010 137 Rfo de La Plata at Highway 2 near Toa Atta (d,c,b,s,p) ......................... 50046000 . ^42 *r * RIO HONDO BASIN Rfo Hondo at Flood Channel near Catano (c,b) .............................. 50047530 148 RIO DE BAYAMON BASIN Rfo de Bayamon at Arenas (d) .......................................... 50047535 150 Rfo Sabana at Vista Monte (d) ...................................... 50047540 152 Lago de Cidra at Damsite near Cidra (e) ................................... 50047550 154 Rfo de Bayamdn below Cidra Dam (d) .................................... 50047560 155 Rfo de Bayamdn near Aguas Buenas (c,b) .................................. 50047600 162 Rfo de Bayamon near Bayamon (d) ...................................... 50047850 164 Rfo Guaynabo near Bayamon (c,b) .................................... 50047990 165 Rfo de Bayamdn at Flood Channel at Bayam6n (c,b,p) ......................... 50048510 167 RIO PUERTO NUEVO BASIN Rfo Piedras: Rfo Piedras at El Senorial (d,s).......................................... 50048770 169 Rfo Piedras near Rfo Piedras (c,b,p) ...................................... 50048800 176 Rfo Piedras at Rfo Piedras (d,s) ......................................... 50049000 178 Rfo Piedras at Hato Rey (d,c,b) ......................................... 50049100 185 Laguna San Jose: Laguna San Jose No 2 at San Juan (c,b) ................................... 50049820 188 Bahfa de San Juan: Bahfa de San Juan No 5 at San Juan (c,b) .................................. 50049920 189 QUEBRADA BLASINA BASIN Quebrada Blasina near Carolina (c,b) ..................................... 50050300 192 RIO GRANDE DE LOIZA BASIN Rfo Grande de Loiza at Quebrada Arenas (d) ................................ 50050900 194 Quebrada Blanca at El Jagual (d,s) .................................... 50051150 195 Quebrada Salvatierra near San Lorenzo (d,s) ............................. 50051180 202 Rfo Cayaguas at Cerro Gordo (d) ..................................... 50051310 208 Rfo Grande de Lofza at Highway 183 near San Lorenzo (d) ..................... 50051800 209 Rfo Turabo above Borinquen (d) ..................................... 50053025 216 Rfo Grande de Lofza at Caguas (d,c,b,s) ................................... 50055000 223 Rfo Caguitas near Aguas Buenas (d) .................................. 50055100 232 Rfo Caguitas near Caguas (d) ....................................... 50055170 239 Rfo Caguitas at Villa Blanca at Caguas (d) .............................. 50055225 241 Rfo Caguitas at Highway 30 at Caguas (c,b) ............................. 50055250 248 Rfo Bairoa at Bairoa (d) ........................................... 50055390 250 Rfo Bairoa near Caguas (c,b)........................................ 50055400 265 SURFACE-WATER AND WATER-QUALITY STATIONS, IN DOWNSTREAM ORDER, IX FOR WHICH RECORDS ARE PUBLISHED IN THIS VOLUME-Continued Station number Page Rio Gurabo: Rio Gurabo below El Mango (d) ..................................... 50055750 267 Rio Valenciano near Juncos (d)x ................................... 50056400 274 Rio Gurabo at Gurabo (d,s) ......................................... 50057000 281 Rio Gurabo near Gurabo (c,b) ....................................... 50057025 282 Rio Cafias at Rio Canas (d,s) ........................................ 50058350 284 Lago Loiza at Damsite (c,b,e) .......................................... 50059000 291 Rio Grande de Loiza below Damsite (d,s) .................................. 50059050 293 Rio Grande de Loiza below Trujillo Alto (c,b) ............................... 50059100 305 Rio Grande de Loiza at Carolina (e) ...................................... 50061000 307 Rio Can6vanas near Campo Rico (d) .................................. 50061800 308 RIO ESPIRITU SANTO BASIN Quebrada Sonadora near El Verde (d) ................................. 50063440 310 Quebrada Toronja at El Verde (d) .................................... 50063500 311 Rio Espiritu Santo near Rio Grande (d,c,b) ................................. 50063800 312 Rio Grande near El Verde (d) ....................................... 50064200 315 RIO MAMEYES BASIN Rio Mameyes near Sabana (d) .......................................... 50065500 316 RIO SABANA BASIN Rio Sabana at Sabana (d) .............................................. 50067000 317 RIO FAJARDO BASIN Rio Fajardo near Fajardo (d,c,b,p) ........................................ 50071000 318 Rio Fajardo below Fajardo (c,b) ......................................... 50072500 321 RIO BLANCO BASIN Quebrada Guaba near Naguabo (d) ....................................... 50074950 323 Rio Icacos near Naguabo (d) ........................................... 50075000 325 RIO HUMACAO BASIN Rio Humacao at Las Piedras (d) ......................................... 50081000 328 Rio Humacao at Highway 3 at Humacao (c,b) ............................... 50082000 329 RIO GUAYANES BASIN Rio Guayanfe at Yabucoa (c,b,p) ........................................ 50083500 331 Rio Guayanes above mouth at Playa de Guayanfe (c,b) ......................... 50086500 333 RIO MAUNABO BASIN Rio Maunabo at Lizas (d) ............................................. 50090500 335 Rio Maunabo at Maunabo (c,b) ......................................... 50091000 336 RIO CHICO BASIN Rio Chico at Providencia (c,b) .......................................... 50091800 338 RIO GRANDE DE PATILLAS BASIN Rio Grande de Patillas near Patfflas (d,c,b) ................................. 50092000 340 RIO SALINAS BASIN Rio Lapas near Rabo del Buey (d) ....................................... 50100200 346 Rio Majada at La Plena (d) ............................................ 50100450 347 A SURFACE-WATER AND WATER-QUALITY STATIONS, IN DOWNSTREAM ORDER, FOR WHICH RECORDS ARE PUBLISHED IN THIS VOLUME-Continued Station number Page RIO COAMO BASIN Rfo Coamo at Coamo (d) .............................................. 50106100 348 Rfo Coamo near Coamo (c,b) ........................................... 50106500 355 RIO DESCALABRADO BASIN Rfo Descalabrado near Los Llanos (d) ..................................... 50108000 357 RIO JACAGUAS BASIN Rfo Toa Vaca above Lago Toa Vaca (d,s)............................... 50110900 358 Rfo Jacaguas at Juana Dfaz (d) .......................................... 50111500 365 RIO INABON BASIN Rfo Inabdn at Real Abajo (d) ........................................... 50112500 368 RIO BUCANA BASIN Rfo Bucana: Rfo Cerrillos above Lago Cerrillos near Ponce (d) ............................ 50113800 369 Lago Cerrillos at Damsite near Ponce (e) ................................... 50113950 370 Rfo Cerrillos near Ponce (d,c,b) ......................................... 50114000 371 Rfo Bucana at Hwy 14 Bridge near Ponce (d) ............................... 50114390 374 RIO PORTUGUES BASIN Rfo Portugues near Ponce (d,c,b) ........................................ 50115000 375 Rfo Portugufe at Ponce (c,b,p) .......................................... 50116200 378 RIO GUAYANILLA BASIN Rfo Guayanilla near Guayanilla (d) ....................................... 50124200 380 Rfo Guayanilla at Central Rufina (c,b,p) ................................... 50124700 381 RIO YAUCO BASIN Lago Luchetti at Damsite (e) ........................................... 50125780 383 RIO LOCO BASIN Rio Loco at GuSnica (c,b,p) ............................................ 50129700 384 RIO GUANAJIBO BASIN Rfo Guanajibo at Highway 119 at San German (d) ............................ 50131990 388 Rfo Guanajibo near San German (c,b) ..................................... 50133600 389 Rfo Rosario near Hormigueros (d,c,b,s) ................................ 50136400 391 Rfo Guanajibo near Hormigueros (d,c,b,p) .................................. 50138000 400 RIO YAGUEZ BASIN Rfo Yaguez near Mayagiiez (c,b) ........................................ 50138800 404 RIO GRANDE DE ANASCO BASIN Lago Guayo near Castaner (e) ....................................... 50141500 406 Rfo Grande de Anasco near Lares (c,b) .................................... 50143000 407 Rfo Grande de Anasco near San Sebastian (d,c,b,s) ............................ 50144000 409 Rfo Grande de Anasco near Anasco (c,b,p) ................................. 50146000 412 RIO CULEBRINAS BASIN Rfo Culebrinas near San Sebastian (c,b) ................................... 50147600 416 Rfo Culebrinas at Highway 404 near Moca (d) ............................... 50147800 418 Rfo Culebrinas near Aguada (c,b,p) ....................................... 50149100 419 SURFACE-WATER AND WATER-QUALITY STATIONS, IN DOWNSTREAM ORDER, XI FOR WHICH RECORDS ARE PUBLISHED IN THIS VOLUME-Continued Station number Page CULEBRA, P.R. Quehrada Resaca near Monte Resaca (e) ................................... 50214500 421 Drainage Canal at Culehra Airport (e) ..................................... 50215000 422 VIEQUES, P.R. Quehrada Cofresf Tributary near Isabela II (e) ............................... 50231000 423 Quehrada La Mina near Esperanza (e) ..................................... 50232000 424 Quehrada Pilon at Colonia Puerto Real (e) .................................. 50233000 425 ST THOMAS, US VIRGIN ISLANDS Bonne Resolution Gut at Bonne Resolution (d) .............................. 50252000 510 Turpentine Run at Mount Zion (d) ....................................... 50274000 511 ST JOHN, US VIRGIN ISLANDS Lameshur Bay Gut at Lameshur (d) ...................................... 50292600 512 Fish Bay Gut at Fish Bay (d) ........................................... 50294000 514 Guinea Gut at Bethany (d) ............................................. 50295000 516 Cruz Bay Gut at Cruz Bay (e) .......................................... 50295500 517 ST CROK, US VIRGIN ISLANDS River Gut at River (e) ................................................ 50332000 518 River Gut near Golden Grove (d) ........................................ 50333500 519 River Gut at Hwy 66 at Fairplanes (d) .................................... 50333700 520 Bethlehen Gut at Hwy 66 at Fairplanes (d) ................................. 50334500 521 Gut 4.5 at Cane Valley (e) ............................................. 50337500 522 Jolly Hill Gut at Jolly Hill (d) .......................................... 50345000 523 Salt River at Canaan (e) .............................................. 50348000 524 Gut 10 near Altona (e) ............................................... 50349000 525 Discharge at partial-record stations and miscellaneous sites Low-flow partial-record stations .......................................... 428 Analyses of samples collected of water-quality partial-record stations and miscellaneous sites ....................................... 442 GROUND-WATER WELLS, BY BASIN, FOR WHICH RECORDS ARE PUBLISHED RIO GUAJATACA BASIN Well 182422067015100 Local number 165 ................................................. 454 Well 182647066552400 Local number 202 ................................................. 455 RIO GRANDE DE ARECIBO BASIN Well 182737066370900 Local number 204 ................................................. 456 RIO GRANDE DE MANATI BASIN Well 182757066325600 Local number 206 ................................................. 457 Well 182710066303700 Local number 207 ................................................. 458 Well 182308066260400 Local number 210 ................................................. 459 RIO CIBUCO BASIN Well 182647066201700 Local number 70 .................................................. 460 Well 182615066235300 Local number 211 ................................................. 461 Well 182515066194000 Local number 212 ................................................. 462 Well 182330066185700 Local number 213 ................................................. 463 RIO DE LA PLATA BASIN Well 182746066170800 Local number 214 ................................................. 464 Well 182530066135400 Local number 216 ................................................. 465 Well 182655066142400 Local number 217 ................................................. 466 RIO HONDO TO RIO PUERTO NUEVO BASINS Well 182623066111000 Local number 218 ................................................. 467 Well 182441066082600 Local number 219 ................................................. 468 Well 182413066044000 Local number 220 ................................................. 469 Well 182511066045401 Local number PN-2 ................................................ 470 Well 182435066052701 Local number PN-5 .................................................... 471 Well 182445066043401 Local number PN-6 ................................................ 472 Well 182437066040501 Local number PN-7 .................................................... 473 Well 182443066041502 Local number PN-8c ............................................... 474 Well 182417066042700 Local number PN-10 ............................................... 475 Well 182349066032600 Local number PN-13 ............................................... 476 Well 182406066034700 Local number PN-19 ............................................... 477 RIO GRANDE DE LOIZA BASIN Well 181550065593201 Local number 50 .................................................. 478 Well 182515065594100 Local number 222 ................................................. 479 Well 181513065554601 Local number CJ-TW3B ............................................. 480 Well 181352066025300 Local number CJ-TW19A ............................................ 481 RIO HUMACAO TO RIO SECO BASINS Well 175858066100200 Local number 6 ................................................... 482 Well 180415065513900 Local number 96 .................................................. 483 U.S. Geological Survey Water Resources Division Caribbean District ERRATA WATER RESOURCES DATA - PUERTO RICO AND THE U.S. VIRGIN ISLANDS, WATER YEAR 1993 1. The period of record for pages 75, 102, 144, 221, 246,263, 303, 304, and 319 containing water-quality data, should read: WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 2. Substitute data on pages 412 and 413 with new data provided on the page accompanying this errata. 3. The heading for pages 445 through 448 should read: ANALYSES OF SAMPLES COLLECTED AT WATER-QUALITY PARTIAL-RECORD STATIONS WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 4. Sediment data for water year 1993 for stations 50055170 Rio Caguitas near Caguas and 50057000 Rio Gurabo at Gurabo, which were not available for publication in this volume, can be obtained through the Caribbean District office. These data will be published in the water year 1994 Data Report. For information call (809) 749-4346. The new address of the U.S. Geological Survey, Caribbean District is: Mailing: GSA CENTER 651 FEDERAL DRIVE SUITE 400-15 GUAYNABO, P.R. 00965 Physical: GSA CENTER HIGHWAY 28, KM 7.2 BLDG. 651, SUITE 400 GUAYNABO, P.R. GROUND-WATER WELLS, BY BASIN, FOR WHICH RECORDS ARE PUBLISHED-Continued XIII Page RIO SALDSfAS TO RIO JACAGUAS BASINS Well 175829066232200 Local number 87 .................................................. 484 Well 180002066132200 Local number HW-TW-01 ........................................... 485 Well 180001066122002 Local number HW-TW-03C .......................................... 486 Well 175947066130601 Local number HW-TW-05B .......................................... 487 Well 175957066123400 Local number HW-TW-13 ........................................... 488 Well 175946066102000 Local number HW-TW-14 ........................................... 489 Well 180206066135500 Local number RM-05 ............................................... 490 Well 180104066152300 Local number RM-10 ............................................... 491 RIO DSfABON TO RIO LOCO BASINS Well 180133066503300 Local number 132 ................................................. 492 Well 175900066354200 Local number 141 ................................................. 493 RIO GUANAJIBO BASIN Well 180132067033800 Local number 143 ................................................. 494 Well 180627067080600 Local number CR-TW-1 ............................................. 495 Well 180628067075800 Local number CR-TW-2A ............................................ 496 Well 180628067075801 Local number CR-TW-2B ............................................ 497 Well 180628067075802 Local number CR-TW-2C ............................................ 498 Well 180643067080400 Local number CR-TW-3 ............................................. 499 Well 180650067073700 Local number CR-TW-4 ............................................. 500 Well 180557067083100 Local number CR-TW-5 ............................................. 501 Well 180617067083300 Local number CR-TW-6 ............................................. 502 Well 180604067085100 Local number CR-TW-7 ............................................. 503 Well 180547067084800 Local number CR-TW-8 ............................................. 504 Well 180628067084300 Local number CR-TW-9A ............................................ 505 Well 180547067073100 Local number CR-TW-10 ............................................ 506 RIO CULEBRINAS BASIN Well 182442067091700 Local number 200 ................................................. 507 ST. CROK, U.S. VIRGIN ISLANDS Well 174225064471900 Local number 1 ................................................... 528 Well 174225064472000 Local number 2 ................................................... 529 Well 174243064475100 Local number 3 ................................................... 530 Well 174245064475800 Local number 4 ................................................... 531 Well 174308064484400 Local number 6 ................................................... 532 Well 174525064460600 Local number 7 ................................................... 533 Well 174527064460100 Local number 8 ................................................... 534 Well 174532064460300 Local number 9 ................................................... 535 Well 174329064454700 Local number 10 .................................................. 536 Well 174303064481100 Local number 11 .................................................. 537 Well 174308064482800 Local number 12 .................................................. 538 XIV GROUND-WATER WELLS, BY BASIN, FOR WHICH RECORDS ARE PUBLISHED-Continued Well 174316064480800 Local number 13 .................................................. 539 Well 174247064475701 Local number 14 .................................................. 540 Well 174319064454401 Local number 15 .................................................. 541 ST. THOMAS, U.S. VIRGIN ISLANDS Well 182038064550300 Local number 6 ................................................... 542 Well 182036064545200 Local number 7 ................................................... 543 Well 182038064580000 Local number 8 ................................................... 544 Well 181917064524600 Local number 9 ................................................... 545 Well 182131064541000 Local number 10 .................................................. 546 Well 182035064550200 Local number 11 .................................................. 547 ST. JOHN, U.S. VIRGIN ISLANDS Well 182010064472600 Local number 1 ................................................... 548 Well 182109064460300 Local number 2 ................................................... 549 Well 182116064451000 Local number 3 ................................................... 550 Well 182044064454800 Local number 7 ................................................... 551 Well 182044064454900 Local number 8 ................................................... 552 Well 182044064455000 Local number 9 ................................................... 553 Well 182044064455200 Local number 10 .................................................. 554 Well 181956064464500 Local number 11 .................................................. 555 Well 182110064430000 Local number 12 .................................................. 556 Well 181950064422300 Local number 13 .................................................. 557 Well 182048064430400 Local number 14 .................................................. 558 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1993 DISCONTINUED STRBAMFLOW STATIONS XV 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 50056900 50058300 50061300 50062500 50063300 50065700 50072000 50073200 50073400 50074000 50075500 50076000 50077000 50077400 50078500 50081500 50082000 50082200 50082800 50083500 50084000 50085100 50086100 50086500 50087200 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 Canny near Lares Rio Criminales near Lares Rio Canny 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 Cambalachc 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 BayanuSn at Bayam6n Quebrada Josefina at Pifiero Avenue Rio Turabo at Borinquen Quebrada de las Quebradillas near Caguas Quebrada Caimito near Juncos Rio Valenciano near Las Piedras Quebrada Mamey near Gurabo Quebrada Arena near Caguas Rio Canovanillas near Loiza Rio Herrera near Colonia Dolores Rio Bspiritu Santo near El Verde Rio Mameyes at Hwy 191 at Mameyes Rio Pajardo at Pajardo 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 Pe 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 Quayanda near Yabucoa Rio Limones near Yabucoa Rio Guayanea at Central Roig Rio del Ingenio at Comunas Rio Guayanes at Playa Guayanes Cafio Santiago near Central Roig Drainage area (mi>) 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 0.54 2.32 8.65 31.90 71.90 3.84 7.89 6.25 0.82 6.85 2.30 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 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 1969 1968 1968 1971 1971 1971 1966 1966 1963 1988- 1984- 1969- 1984- 1971 1984 1971 1968 1968 1968 66,71 •72 •69,71 •71 -75 -67 91 90 71,73 87 •92 •73 •72 •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 XVI WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1993 DISCONTINUED STREAMFLOW STATIONS--Continued Station number 50091000 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 at Maunabo 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 Quayama Rio Guamani near Guayama Quebrada Aguas Verde8 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 Arus Rio Inabon at Coto Laurel Rio Guayo near Coto Laurel Rio Inab6n near Arus Rio Bucana near Ponce Rio Bucana near Playa de Ponce Rio Portugues at Hwy 14 at Ponce Rio Portugues at Highway 2 Bypass at Ponce Rio Matilde at Ponce Rio Tallaboa at Pefiuelas Rio Tallaboa at Tallaboa Rio Guayanilla nr Guayanilla Rio Guayanilla at Guayanilla Rio Duey above Diversion near Yauco Rio Yauco above Diversion Mbnserrate 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 Afiasco at El Espino Rio Culebrinas at San Sebastian Turpentine Run at Mariendal Drainage area (mi » 12.40 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 1965,67, 1969-82 1971-72 1965-73 1965, 1969-72 1965, 1967-69, 1971 1967, 1969, 1971 1971 1965,1969, 1970-71, 1973 1969-71 1969-70 1989 1967-68 1984-85, 1986 1967-68 1967-68 1965, 1967-71 1966-67 1966-70 1966-68 1989 1966-67 1967-71 1965, 1968-71 1964-65 1965-81 1964-67 1965-82 1964-65 1965-66 1959-82 1959-63 1961-69 1971-82 1977-80 1978-85 1962-64, 1977-85 1963-67 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, 1993 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, 1993." This report includes records on both surface and ground water. Specifically, it contains: (1) Discharge records for 81 streamflow-gaging stations, stage only for 12 gaging stations, daily sediment records for 21 streamflow stations, 112 partial-record or miscellaneous streamflow stations, stage records for 11 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 86 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, 1991 and 1992 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, mis volume is identified as "U.S. Geological Survey Water-Data Report PR-93-1". 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. * WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1993 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 Legislature Puerto Rico Civil Defense Water Resources Research Institute, College of the Virgin Islands U.S. Virgin Islands Water and Power Authority 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, 1993 3 SUMMARY OF HYDROLOGIC CONDITIONS Precipitation Precipitation throughout Puerto Rico during the 1993 water year (October 1992 to September 1993) averaged about 103 percent of normal. However, precipitation was 98 percent of normal in northern Puerto Rico, 106 percent of normal in southern Puerto Rico, 105 percent of normal in eastern Puerto Rico, and 105 percent of normal in western Puerto Rico. Monthly average precipitation islandwide for the 1993 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 1993 water year and the 30-year reference period, 1951-80 1993 Water Year 30-year normal Month (inches) (inches) OCT 6.40 7.74 NOV 8.94 5.95 DEC 5.23 4.32 JAN 3.91 3.08 FEE 1.92 2.35 MAR 2.03 2.62 APR 6.76 4.63 MAY 8.02 6.48 JUN 5.36 5.58 JUL 5.91 5.48 AUG 4.23 7.28 SEP 6.51 7.78 TOTAL 65.22 63.29 Surface Water Streamflow at the four index stations in Puerto Rico generally was above normal during water year 1993 although no significant floods occurred during the year. Figure 1 compares monthly-mean flows at the four index stations on the Rio Grande de Anasco, the Rio Grande de Manatf, the Rio Inabon, and the Rio Fajardo during water year 1993 with the long-term median of monthly-mean flows. Maximum and minimum monthly flows for each of these index stations for the period of record are also shown in figure 1. In the western area, the Rio Grande de Anasco near San Sebastidn had monthly-mean flows that exceeded the long-term median of monthly-mean flow every month except July and August which had monthly-mean flows of 76 and 77 percent of the long-term median. MONTHLY-MEAN DISCHARGE, IN CUBIC FEET PER SECOND T] CQ' c o 0 Q. O <§0 O^ to Q. 0) 3 Q} 0) C 0 Oo ac » I! a — w CD -i CDIs II MONTHLY-MEAN DISCHARGE, IN CUBIC FEET PER SECOND WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1993 » In the northern area, streamflow at the index station on the Rio Grande de Manati at Highway 2, was above normal during much of the year and the monthly-mean flow in April and May were 325 and 322 percent of the long-term median of monthly-mean flows. Monthly-mean flows were below the long-term median of monthly-mean flows in October, March, and August with 72 to 98 percent of the long-term median. In the southern area, monthly-mean flow at the Rio Inabon at Real Abajo index station was above the long-term median of monthly-mean flow most of the water year 1993. During May the monthly-mean flow at this site was 475 percent of the long-term median. Only during December, August, and September were monthly-mean flows below the long-term median of monthly-mean flows. In the eastern area, streamflow at the Rio Fajardo near Fajardo index station, was above the long-term median of monthly-mean flow during November, December, January, and July, but was below the long-term median during much of the year. At the beginning of water year 1993, monthly-mean flow in the Rio Fajardo was only 27 percent of the long-term median of monthly-mean flow. From November to January monthly-mean flows ranged from 122 to 330 percent of the long-term median. In February and March streamflow declined seasonally and monthly-mean flows were below normal. In August, the monthly-mean flow at this station was the lowest of record. Ground-Water Levels Ground-water levels in the major aquifers of Puerto Rico followed a seasonal trend associated with rainfall patterns during water year 1993. Water levels generally rose as significant rainfall events recharged the coastal aquifers. Record-high water levels were recorded at several wells in Puerto Rico and the U.S. Virgin Islands (table 2). Ground-water levels in the north coast limestone aquifer, at the Sabana Hoyos index well (fig. 2) rose from November to early January 1993. Water levels in this well then declined until late April, when above normal rainfall reversed the trend. Water levels were relatively stable from mid-May until early August, but declined gradually during late August and September. Ground-water levels in the south coast alluvial aquifer at the Alomar index well (fig. 2) were relatively stable during October and November 1992, but declined about 3.4 feet, from December 1992 to April 1993. Water levels rose about a foot in this well during May as a result of above normal rainfall along the south coast, but remained relatively stable from June to September 1993, except for fluctuations, due to ground-water withdrawals for public, irrigation, and industrial uses. Water levels in this well were about 2 feet lower at the end of the water year than at the start of the water year. Ground water in observation well 11 at Guinea Gut, St. John in U.S. Virgin Islands rose sharply in response to rainfall events during November and December 1992 and January, February, and June 1993 (fig. 2). From February to mid-June 1993 the water levels in Guinea Gut well declined about 12.5 feet in response to below normal rainfall in the area. 6 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1993 Table 2. Highest ground-water levels recorded during 1993 water year and previous high ground-water levels at selected wells in Puerto Rico and the U.S. Virgin Islands. [PR, Puerto Rico; 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; +, above land-surface datum] Well name or Local number number Location Saltos 1 165 PR La Esperanza PN-2 PR 2 Salud Mental PN-5 PR 5 Las Am&ricas PN-10 PR 10 Jardln Botdnico PN-19 PR 3 CJ-TW 19A CJ-TW 19A PR CR-TW-1 CR-TW-1 PR CR-TW-2A CR-TW-2A PR CR-TW-2B CR-TW-2B PR CR-TW-2C CR-TW-2C PR CR-TW-3 CR-TW-3 PR CR-TW-4 CR-TW-4 PR CR-TW-5 CR-TW-5 PR CR-TW-6 CR-TW-6 PR CR-TW-7 CR-TW-7 PR CR-TW-8 CR-TW-8 PR CR-TW-9A CR-TW-9A PR CR-TW-10 CR-TW-10 PR VIEO-6 8 St.T VIEO-4 14 St.J 1993 highest water level (ft-blsd) 38.40 8.01 25.37 + 2.30 3.35 22.78 + 4.75 + 4.00 + 4.34 +3.94 + 5.40 2.99 2.12 1.44 11.15 5.60 + 0.24 2.98 22.79 9.57 Date (mm-dd-yy) 07-12-93 12-30-92 12-31-92 02-05-93 01-09-93 01-10-93 01-11-93 01-12-93 12-30-92 07-27-93 10-12-92 10-12-92 10-10-92 10-10-92 10-11-92 10-12-92 10-12-92 10-12-92 10-12-92 10-05-92 10-12-92 10-12-92 01-21-93 01-06-93 01-07-93 Previous highest water level (ft-blsd) 38. 8. 26. + 2. 4. 23. + 3, + 2. + 2. + 1. + 4, 3. 3. 4. 14, 7. 1. 5. 23. 9, ,75 .07 .20 .04 .04 .78 .11 .06 .71 .96 .24 .55 .78 .00 .20 .02 .36 .17 .27 .95 Date (mm-dd-yy) 09-23-92 09-26-92 06-08-92 06-09-92 06-10-92 11-21-89 11-22-89 10-22-90 06-09-92 11-16-91 09-08-92 09-15-92 09-08-92 09-15-92 09-15-92 09-26-92 09-15-92 09-15-92 09-15-92 09-25-92 09-09-92 09-15-92 10-14-91 06-05-92 Period of record (mm-yy) 1-82 6-89 4-89 10-89 6-91 9-91 7-92 7-92 6-92 6-92 3-92 6-92 7-92 6-92 6-92 6-92 7-92 7-92 10-91 5-91 to to to to to to to to to to to to to to to to to to to to 9-93 9-93 9-93 9-93 9-93 9-93 9-93 9-93 9-93 9-93 9-93 9-93 9-93 9-93 9-93 9-93 9-93 9-93 9-93 9-93 Zl (Qi ho 3 a. WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM 3 SL . _ a> §"3" 3 CL to5" ? <D irt O4 to at en 01 o B CD TJ 70 O m "O oq O8 > 70 C Z O m 25z 0> °xI WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1993 Water Quality In water year 1993, the U.S. Geological Survey, in cooperation with local government agencies, collected water- quality data at 72 surface-water station in Puerto Rico. The water-quality data collected at these stations includeJdMhe major chemical constituents and several additional constituents that are listed in table 3. The highest concentration of these additional constituents detected during water year 1993 and the stations which these concentrations were detected are summarized in table 3. Table 3. Surface-water quality stations in Puerto Rico with highest concentration of selected constituents during water year 1993 [All constituent concentrations are in milligrams per liter; MBAS, Methylene blue active substance] Station number Station name Constituent Concentration 50010500 50475300 50083500 50116200 50011000 50091800 50091800 50055250 Rio Guajataca at Lares Rio Hondo at Flood Channel near Catafio Rio Guayan6s near Yabucoa Rio Portugu£s at Ponce Canal Diversi6n at Lago Guajataca Rio Chico at Providencia Rio Chico at Providencia Rio Caguitas at Highway 30 at Caguas Sulfide Boron Manganese Iron Zinc Cyanide Phenols MBAS 1.6 5.0 1.1 21 .31 .03 .10 .009 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 1993. A bacteria concentration exceeding one million colonies per hundred milliliters of raw water was determined for a water sample collected at the station on Rfo Piedras at Rio Piedras (50049100). This station is located in the San Juan metropolitan area, which has the highest population concentration in Puerto Rico. In addition to the effluent from the San Juan metropolitan area Rio Piedras also receives from the areas in the upper basin sewage treatment plants service in urban and suburban. 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 coliform and fecal streptococci bacteria in surface waters in Puerto Rico generally were in heavily populated an industrialized areas of the island. Suspended sediment concentrations were monitored at 19 stations in Puerto Rico during the 1993 water year as part of the cooperative program between the U.S. Geological Survey and various Commonwealth and Federal agencies. High suspended sediment concentrations are a common problem in many streams in Puerto Rico. Most of the streams with high suspended sediment concentration were related to land use, especially construction of urbanizations and roads, agriculture and activities where soil movement was involved. The high suspended sediment concentrations affects the water quality for drinking water and decrease the storage capacities of reservoirs used for water supply. 9 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1993 SPECIAL NETWORKS AND PROGRAMS Hydrologic Bench-Mark Network is a network of 57 sites 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. 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. The National Trends Network (NTN) is a 150-station 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). The National Water-Quality Assessment (NAWQA) Prgram of the U.S. Geological Survey is a long-term program with goals to describe the status and trends of water-quality conditions for a large, dirverse, and geographically distributed part of the Nation's ground- and surface-water resources, and to identify, describe, and explain the major natural and human factors that affect these observed conditions and trends. Assessment activities have begun in more than one-third of the study units and ultimately will be conducted in 60 study units (major watersheds and aquifer systems) that represent a wide range of environmental settings nationwide and that account for a large percentage of the Nation's water use. A wide array of chemical constituents will be measured in ground water, surface water, streambed sediments, and fish tissues. The coordinated application of comparative hydrologic studies at a wide range of spatial and temporal scales will provide information for decision making by water- resources managers and a foundation for aggregation and comparison of findings to address water-quality issues of regional and national interest. Radiochemical Programs is a network of regularly sampled water-quality stations where samples are collected to be analyzed for radioisotopes. The streams that are sampled represent major drainage basins in the conterminous United States. 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 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 precipitation stations. The purpose of the precipitation stations is to provide an estimate sufficient for hydrologic studies of the tritium input to the United States. EXPLANATION OF RECORDS The surface- and ground-water records published in this report are for the 1993 water year that began October 1, 1992 and ended September 30, 1993. 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. 1 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1993 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). 67 00 •1b ATLANTIC 66'00 6*30 "'"""1 * sx •*-v -' i ; >./ \\~ i \.Mv^M. \ '' • X f' r CARIBBEAN SEX! •^_ > • •'"••) MnMT ' \ Hd/iH) EXPLANATION FECAL COLIFORM • < 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. ATLANTIC ,-> X <<: EXPLANATION FECAL STREPTOCOCCI ^ 1000-10,000 4 10,000-100,000 ^ 100,000-1,000,000 ^^ > 1,000,000 Figure 4.-Location of fecal streptococci bacteria concentration at sampled sites. 65 ATLANTIC OCE-V SE4 EXPLANATION 0920 CONTINOUS STREAMFLOW STATION AND NUMBER 1415 LAKE-ELEVATION STATION Figure 5.-Location of surface-water stations in Puerto Rico. 10 20 ATLANTIC 0395 OS8320 / J / y-'w ^ & CARIBBEAN SEA Cfc.jj.fjn«« EXPLANATION QUALITY OF WATER STATIONS ^0430 BIOLOGICAL ^f 0820 CHEMICAL ^0280 SEDIMENT (Daily) yosio SEDIMENT (Bi-monthly) Figure 6.--Location of water-quality stations in Puerto Rico. 15' EXPLANATION A LOW-FLOW PARTIAL-RECORD STATION 1107 STATION IDENTIFICATION NUMBER 18W Vo Gusnaj^o ^l&y * ,A 1383 A X A \ .13824A/LA 1£ 1109 ) X'1381' ("",,,.. Al338x Ik • i ^A^-fr^(T^x4 i3^A^ A33V 31^, A //E£fe A 7 >* A!43108 L^423 \ J ——, "'X*/ °4Z^, / Y\ "'Ai4i4 AAn 38^, vxr " ' "X ) Ai°4° ; / 4 \ ZA A 1 —v 113790 A v ^A 110550 .A-xx A / / 120550 114g: \ 1128' ^ ^ (- A!3'\ ^AA^f&^A '. M68 ' ^—M VMi^fcn j 1,256 ___ AI 25860 fX"^ 255 A _x— so—^ Ui 0i — 0 L__________A 10 20 I i 10 30 KILOMETERS 20 MILES ,,,,r,-,,-l ————— f —————— , ———————— -r;,-<-,-, ••„-,•-, -„--„-,•,--, ,--, ,— - .—--———„ . SE^ _J ____—_._-_., .L—..... ._.... . i — „ ......,., » Figure 7.-Location of low-flow partial-record stations in southwest Puerto Rico. 0) 65 a>.£/», ,-- /*t' ^"V c\\ x ATLANTIC OCEAN i, t*202 CR-TW-6 CR-TW-9A ' 0212 •,216 219'* 213 J \ \ ^ -.-—- C \ OH /t-i. / V— -. X\ ^ \^r^i^,' JHW-TW-01 HW-TW-05B , RM-05'0 1 •> • u RM-10 HW/-TW-03C ' HW-TW-13 "''1 1 , • ."" f s HW-TW-14 KJ S < < ^ CARIBBEAN SEA EXPLANATION • 6 WELL AND WELL NUMBER Figure 8.--Location of ground-water stations in Puerto Rico. 18'24' ST. THOMAS 17 64 50 -V ^2520 l 1 >s-- " A2740 \ A x <£-£» !7a45! 45' 81 JOHN C « ffM^ __f "^tar*^ AJ " > ^ .-^ s"~ { /---' .,./ ; A'" \ / ,A V / / 2950 ^2940 _JT~H-,, y x- r ?v ' A ^** -- s ? x> ^^^^348o]t^"'' / \ 3450A' ,- -^ -. N \ ^ \ ^ ' \j \A?375 ; ! ^iks*-i r 1 3336Aj43345 y"" aic'~ \ ( 3337 ^ Ci Ksstianf.tr-; •• ^•/ A 3490 64 40' 6435' i EXPLANATION 012. -; K!LO,.,c; ,£RS ^3490 SURFACE-WATER STATION AND NUMBER k 3 4 MILES 1 Figure 9.--Location of surface-water stations in the U.S. Virgin Islands. 01224 KILOMETERS i 'L-,-, 01234 MILES XJ <J 1234 KILOMETERS _1 i ! 2 3 4 MILES V EXPLANATION WELL AND WELL NUMBER 6450 7'45' 1740'f- 01234 f./t'LEi Figure 10.--Location of ground-water stations in the U.S. Virgin Islands. S5C 32'30" 65«30'OG" 65«27'3C" S5°25'OG" 65*22*30" 65020TOO" 19 18°10'00" 18°07'30" 18°C5'CG" 1 2 KILOMETERS I 2 MiLES EXPLANATION A 2310 SURFACE-WATER STATION AND NUMBER 65"20'00' : 17' 30" Isla de CuSebra, P.R. o i 2 KILOMETERS o 1 2 MILES EXPLANATION A 2145 SURFACE-WATER STATION AND NUMBER Figure 11.-Location of surface-water stations in Vieques and Culebra Islands. 20 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1993 66°53* 52' 51' 50' 49' 48' 66°47' in°n?' or I8°00' 17059' 134 132^ 131* \ V, *16 jr •27 •74 C</c COORDINATES FOR WELLS 27 (180150066474000) AND 74 (180136066471000) COORDINATES FOR WELLS 132 (180133066603300) ^ AND 134 (160120066603200) COORDINATES FOR WELL 131 (180068066602700) COORDINATES FOR WELL 16 (176922066406800) 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 titles 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. WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1993 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. 22 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1993 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.--A11 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. WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1993 23 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 mat 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). 4 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1993 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 area! 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 ftVs; to whole numbers between 10 and 1,000 ftVs; and to 3 significant figures for more than 1,000 ftVs. 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. WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1993 25 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. 26 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1993 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, suspended-sediment loads for other periods of similar discharge, and computed by the subdivided-day method using the transport curves. 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 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, Fla. 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. WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1993 27 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. apply. 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 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. 28 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1993 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. WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1993 29 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 (or below) sea level; it is reported with a 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. 30 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1993 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 in, 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. WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1993 3 1 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. 2 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1993 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. 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 periphyton 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. Chlorophyll refers to the green pigments of plants. Chlorophyll ai 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. WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1993 33 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. Cubic foot per second (ftVs) 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 (ftYs/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 concentrationsrof 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 ni 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. 34 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1993 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. 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 lamer. 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 mat 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 mat 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 4. WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1993 Table 4. Factors for conversion of chemical constituents in milligrams per liter to millieguivalents per liter. Ion Multiply by Aluminum (Al-t-3 )*........ 0.11119 Ammonia as NH4+1........ .05544 Barium (Ba+2)........... .01456 Bicarbonate (HC03-1).... .01639 Bromide (Br-1).......... .01251 Calcium (Ca-t-2) .......... .04990 Carbonate (C03-2)....... .03333 Chloride (Cl-1) ......... .02821 Chromium (Cr-t-6) *........ .11539 Cobalt (Co+2)*.......... .03394 Copper (Cu-t-2)*. ......... .03148 Cyanide (CN-1).......... .03844 Fluoride (F-l).......... .05264 Hydrogen (H-t-1) .......... .99209 Hydroxide (OH-1)........ .05880 Ion Iodide (1-1)......... Iron (Fe-t-3).......... Lead (Pb-t-2) .......... Lithium (Li-t-1) ....... Magnesium (Mg-t-2)..... Manganese (Mn+2)*.... Nickel (Ni-t-2) ........ Nitrate (N03-1)...... Nitrite (N02-1)...... Phosphate (PO4-3).... Potassium (K+l)...... Sodium (NA-t-1) ........ Strontium (Sr-t-2)..... Sulfate (S04-2)...... Zinc (Zn-t-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 enumerated 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. 36 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1993 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 (IX 10-l2) of the amount of ratioactivity represented by a curie (Ci). A curie is the amount of radioactivity that yields 3.7 x 10l° 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 those 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. WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1993 3 7 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 fmg C/(m2.time)1 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 periphyton and macrophytes and [mgO /(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 is 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 influenced 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. 38 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1993 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). 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 (ft^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. Streatnflow 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. WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1993 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. Suriicial 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. 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 particulate 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...........................Lnsecta 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. 40 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 1993 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. 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 particulate 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. PUBLICATIONS ON TECHNIQUES OF WATER-RESOURCES INVESTIGATIONS 41 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 called 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 M. 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. 42 PUBLICATIONS ON TECHNIQUES OF WATER-RESOURCES INVESTIGATIONS-Continued 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. 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- -TWRI 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. 0. 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. Kilpatrick, 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- TWRI 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-B4. Supplement 1. Regression modeling of ground-water flow - Modifications to the computer code for nonlinear regression solution of steady-state ground-water flow problems, by R. L. Cooley. USGS- -TWRI Book 3, Chapter B4. 1993. 8 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. 0. 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. PUBLICATIONS ON TECHNIQUES OF WATER-RESOURCES INVESTIGATIONS-Continued 43 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. 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 01.1970.17 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 LL 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. 6-A3. A modular finite-element model (MODFE) for area/ and axisymmetric ground-water-flow problems. Part 1: Model Description and User's Manual, by L. J. Torak: USGS-TWRI Book 6, Chapter A3.1993. 136 pages 6-A4. A modular finite-element model (MODFE) for area! and axisymmetric ground-water-flow problems, Part 2: Derivation of finite-element equations and comparisons with analytical solutions, by R. L. Cooley: USGS-TWRI Book 6, Chapter A4. 1992. 108 pages. 6-A5. A modular finite-element model (MODFE) for areal and axisymmetric ground-water- problems, Part 3: Design phitosophy and programming details, by L. J. Torak. USGS-TWRI Book 6, Chapter AS, 1993. 243 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. 44 PUBLICATIONS ON TECHNIQUES OF WATER-RESOURCES INVESTIGATIONS-Continued 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. Garter 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 Book 8, Chapter B2.1968.15 pages. Surface and Quality-of-Water Records for Puerto Rico 46 THIS PAGE WAS LEFT BLANK INTENTIONALLY 47 ATLANTIC OCEAN Dromog* boyndofif* indtt*rminate in iimviton* tt rron* %^-1 -•—( -? i'o Grants d* \ ir Afto»co bo tin EXPLANATION A 0105 SURFACE-WATER STATION AND NUMBER V°io5 QUALITY-OF-WATER STATION AND NUMBER Voio72o QUALITY-OF-WATER PARTIAL RECORD STATION AND NUMBER • 165 WELL AND WELL NUMBER 0123456 KILOMETERS C 1 2 3 4 MILES Figure 13.--Rio Guajataca basin. 48 RIO GOAJATACA BASIN 50010500 RIO GOAJATACA 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 An6n, and 0.4 mi (0.6 km) east of Lares. DRAINAGE AREA.--3.16 mi» (8.18km'). 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 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG 1 22 29 2 12 17 3 7.9 13 4 6.3 12 5 5.9 10 6 5.4 9.2 7 5.0 8.2 8 5.3 7.6 9 4.5 7.1 10 14 7.1 11 6.6 6.4 12 4.9 5.9 13 4.4 5.7 14 4.0 11 15 3.8 7.2 16 23 5.8 17 23 5.8 18 33 12 19 27 5.7 20 19 4.6 21 14 4.4 22 14 4.3 23 15 3.9 24 14 3.8 25 11 3.8 26 10 4.9 27 9.5 6.1 28 8.5 3.9 29 22 8.8 30 25 7.6 31 33 TOTAL 413.0 241.8 MEAN 13.3 8.06 MAX 33 29 MIN 3.8 3.8 AC-FT 819 480 CFSM 4.22 2.55 IN. 4.86 2.85 STATISTICS OF MONTHLY MEAN MEAN 18.6 10.1 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 4.5 3.9 4.0 3.3 3.0 2.8 2.6 2.4 2.4 2.7 2.2 2.1 11 7.8 4.7 2.5 2.8 2.4 2.2 3.0 2.7 2.7 2.1 1.9 1.8 2.3 1.9 1.7 13 4.1 2.4 108.9 3.51 13 1.7 216 1.11 1.28 DATA 3.72 7.31 1971 1.35 1991 FOR 1.9 1.6 1.6 1.4 1.6 1.4 1.4 1.4 1.2 1.1 1.1 1.1 1.1 1.0 1.1 1.1 1.2 1.2 1.2 1.1 1.7 2.0 .94 .86 .85 1.2 .94 1.8 7.3 3.4 2.3 49.09 1.58 7.3 .85 97 .50 .58 5.6 1.1 e3.7 2.5 1.4 3.0 2.0 1.1 3.4 1.7 1.3 2.3 1.8 1.6 1.6 1.6 1.5 1.5 1.5 c .92 1.9 .88 3.6 .82 1.8 .76 1.9 .82 1.5 .82 1.5 9.90 12 1.5 el. 2 3.9 1.4 1.4 1.3 1.3 1.4 1.3 1.3 2.3 1.7 1.2 1.5 .99 1.0 .92 .96 .80 19 .84 11 .86 20 .82 6.2 .86 11 .85 18 .83 5.1 .80 7.2 .82 14 .82 18 .78 13 .79 6.1 .81 5.6 .85 3.7 .80 3.0 1.0 el. 5 11 el. 5 12 e.96 4.5 e5.6 45.37 33.91 228.9 1.62 1.09 7.63 5.6 .92 90 .51 .53 FOR HATER YEARS 1969 - 2.53 6.83 1971 .66 1991 5.6 20 .76 1.5 67 454 .35 2.41 .40 2.69 1993, BY HATER 2.20 2.27 4.30 5.37 6.38 7.63 1971 1971 1993 .93 1.01 1.31 1992 1970 1970 1992 CALENDAR YEAR 1586.45 4.33 33 .61 .67 3150 1.37 18.68 10 2.4 .88 Oct 18 Mar 23 Mar 17 3.1 4.1 42 12 5.3 35 48 24 17 10 7.9 6.5 4.9 4.8 4.3 15 6.2 4.8 4.3 6.0 3.5 14 15 5.6 4.3 3.8 3.5 22 6.2 27 27 397.1 12.8 48 3.1 788 4.05 4.67 YEAR (WY) 9.87 12.8 1993 3.86 1992 14 9.7 9.0 7.4 7.1 7.7 5.5 9.8 22 7.1 8.9 13 8.3 5.8 5.0 5.6 4.6 4.3 7.6 5.4 4.3 4.1 4.0 4.3 3.8 3.5 3.5 3.2 11 4.5 —— 214.0 7.13 22 3.2 424 2.26 2.52 7.00 9.73 1970 3.18 1992 FOR 1993 HATER YEAR 2130.07 5.84 48 .76 .81 463 10.96 4220 1.85 25.08 14 3.2 1.1 May 7 Mar 8 Mar 19 May 3 May 3 3.1 3.1 3.0 3.0 2.6 2.7 2.3 2.7 2.2 2.2 2.3 2.7 2.0 2.7 2.8 3.3 3.2 2.7 2.8 2.7 2.5 9.1 3.6 4.0 1.9 6.8 2.4 1.7 2.6 2.3 2.2 93.2 3.01 9.1 1.7 185 .95 1.10 4.22 9.85 1969 2.03 1990 HATER 6 8 4 216 5300 21 4490 1 26 14 3 2.3 2.3 2.4 2.2 2.0 3.1 2.4 1.9 1.9 2.2 3.2 2.0 1.7 1.6 1.5 14 2.6 2.1 6.3 2.0 1.8 1.8 1.7 1.7 10 3.8 2.0 4.8 9.1 14 16 126.4 4.08 16 1.5 251 1.29 1.49 5.13 9.88 1991 3.34 1970 YEARS 1969 .20 .05 .70 Oct .47 Jan .51 Jan Oct .30 Oct .96 .67 .6 .94 12 3.9 1.7 2.4 16 30 37 14 6.1 8.7 4.2 3.0 3.6 2.2 1.9 1.5 1.4 1.5 6.1 1.8 1.0 1.9 2.4 1.7 2.0 3.5 1.5 2.8 1.4 1.2 178.4 5.95 37 1.0 354 1.88 2.10 10.7 15.7 1990 5.95 1993 - 1993 1991 1992 7 1990 13 1991 9 1991 7 1990 7 1990 e Estimated 49 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 ml (0.2 km) upstream from Quebrada Anon, and 0.4 ml (0.6 km) northeast of Lares plaza. DRAINAGE AREA.--3.16 mi 9 (8.18 km'). PERIOD OF RECORD.--Water years 1958-71, 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 30... DEC 15... FEB 1993 17... APR 15. .. JUN 17... SEP 22... TIME 1115 0940 0945 1035 0855 1115 DIS- CHARGE, INST. CUBIC FEET PER SECOND 8.1 4.3 1.2 3.4 4.8 1.0 SPE- CIFIC CON- DUCT- ANCE (US/CM) 215 212 233 254 236 258 PH WATER WHOLE FIELD (STAND- ARD UNITS) 6.9 7.3 7.4 7.2 7.1 7.3 TEMPER- ATURE WATER (DBG C) 22.5 22.0 21.0 21.0 22.5 23.5 TUR- BID- ITY (NTU) 32 11 2.1 49 23 1.6 OXYGEN, DIS- SOLVED (MG/L) 4.8 4.8 4.4 7.8 7.6 7.3 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 56 56 50 91 87 85 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 13 20 11 19 <10 16 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K2200 25000 K620 K18000 K1700 850 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 2100 47000 2400 K41000 3500 2000 DATE OCT 1992 30... DEC 15... FEB 1993 17... APR 15... JUN 17... SEP 22... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MG/L TOT FLD SOLVED AS CAC03) CAC03 MG/L AS (MG/L MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS NA) 73 2 19 6.3 10 100 5 32 5.8 11 98 4 28 6.5 13 SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY SIUM, WAT WH DIS- SOLVED AS K) 0.6 3.4 0.5 3.5 0.6 2.8 CHLO- SULFATB RIDE, TOT PET SULFIDE DIS- DIS- FIELD TOTAL SOLVED SOLVED (MG/L MG/L AS (MG/L CAC03 78 74 100 95 89 90 (MG/L <0.5 11 1.6 15 12 (MG/L AS S) AS S04) AS CL) 10 11 10 SOLIDS, RESIDUE DATE OCT 1992 30... DEC 15.. . FEB 1993 17... APR 15.. . JUN 17... SEP 22.. . FLUO- RIDE, DIS- SOLVED (MG/L AS F) <0.10 -- -- <0.10 -- 0.20 SILICA, DIS- SOLVED (MG/L AS SI02) 25 -- -- 22 — 31 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 126 -- -- 157 -- 170 SOLIDS, DIS- SOLVED (TONS PER DAY) 2.76 -- -_ 1.44 — 0.46 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 56 6 3 40 12 2 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 1.99 1.67 1.89 1.15 0.68 1.19 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.010 0.030 0.010 0.050 0.020 0.010 NITRO- GEN, N02+N03 TOTAL (MG/L AS N) 2.00 1.70 1.90 1.20 0.70 1.20 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.020 0.060 0.160 0.140 0.030 0.030 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) -- 0.74 0.94 0.36 0.17 0.77 non-Ideal count 50 RIO GOAJATACA BASIN DATE OCT 1992 30... DEC 15... FEB 1993 17.. . APR 15... JUN 17... SEP 22... DATE OCT 1992 30... DEC 15... FEB 1993 17.. . APR 15.. . JUN 17... SEP 22.. . 50010500 RIO GOAJATACA AT LARBS, PR- -Continued HATER-QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) •eO.20 0.80 1.1 0.40 0.30 0.80 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) 2.0 2.5 2.3 2.1 0.90 1.9 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N03) 10 11 13 10 4 12 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.060 0.060 0.060 0.090 0.060 0.070 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) ARSENIC TOTAL (UG/L AS AS) •el -- -- 1 -- -- SELE- NIUM, TOTAL (UG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) •elOO — — <100 — — SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) ,10 -- -- 30 -- -- ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) •el — — <1 — — CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) •el -- -- <1 -- -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) 20 — — 10 — -- MBTHY- LBNB BLUE ACTIVE SUB- STANCE (MG/L) 2000 890 790 90 <0.10 <0.10 -el •el 210 10 •cO.010 <0.010 0.03 0.04 RIO GOAJATACA BASIN ** ' 50011000 CANAL PRINCIPAL. DE DIVBRSIONBS AT LAGO DE GUAJATACA, PR HATER-QUALITY RECORDS LOCATION.--Lat 18°24'02", long 66°55'27", off Highway 476 at Lago Guajataca outlet, 3.0 mi (4.8 km) southwest of Segunda Unidad Baldorioty de Castro, and 5.3 mi (8.5 km) south of Quebradillas Plaza. DRAINAGE AREA.--Indeterminate. PERIOD OF RECORD.--Hater years 1958-64, 1974 to current year. HATER-QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 27... DEC 16. .. FEB 1993 23. .. APR 27. .. JUN 15. .. SEP 10... TIME 1105 1245 1240 1450 1200 1145 DIS- CHARGE, INST. CUBIC FEET PER SECOND ESS ESS ESS ESS ESS ESS SPE- CIFIC CON- DUCT- ANCE (US/CM) 317 315 312 293 310 330 PH HATER WHOLE FIELD (STAND- ARD UNITS) 7.1 7.1 7.4 6.7 7.0 7.4 TEMPER- ATURE HATER (DEG C) 27.0 26.0 25.5 24.5 25.0 26.0 TUR- BID- ITY (NTU) 1.2 0.80 0.70 1.4 1.0 1.4 OXYGEN, DIS- SOLVED (MG/L) 0.2 1.2 1.6 0.5 0.4 0.7 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 2 58 20 36 18 21 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 12 12 67 29 <10 <10 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 34 K4 10 K160 40 28 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 29 K8 10 K110 94 30 DATE OCT 1992 27. .. DEC 16. .. FEB 1993 23... APR 27. .. JUN 15. .. SEP 10. .. HARD- NESS TOTAL (MG/L AS HARD- NESS NONCARB CALCIUM WH HAT TOT FLD DIS- SOLVED MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED MG/L AS (MG/L (MG/L 130 4 48 140 12 50 140 11 50 (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) SODIUM AD- SORP- TION RATIO ALKA- POTAS- UNITY CHLO- SIUM, HAT WH SULFATE RIDE, DIS- TOT PET SULFIDE DIS- DIS- SOLVED FIELD TOTAL SOLVED SOLVED (MG/L MG/L AS (MG/L (MG/L (MG/L AS K) 3.3 5.4 0.2 1.8 3.5 5.6 0.2 2.1 4.2 5.7 0.2 1.9 CAC03 160 78 140 180 140 130 AS S) AS S04) AS CL) <0.5 9.7 0.8 8.4 6.3 6.6 8.0 7.9 SOLIDS, RESIDUE DATE OCT 1992 27... DEC 16... FEB 1993 23... APR 27... JUN 15... SEP 10... FLUO- SILICA, RIDE, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS AS F) SI02) <0.10 7.7 __ __ 0.10 4.5 __ 0.10 7.2 SUM OF SOLIDS, CONSTI- DIS- TUENTS, SOLVED DIS- (TONS SOLVED PER (MG/L) DAY) 160 __ _- 190 -- 174 TOTAL AT 105 DEG. C, SUS- PENDED (MG/L) 4 <1 <1 1 11 5 NITRO- GEN, NITRATE TOTAL (MG/L AS 0 0 0 0 1 N) -- .090 .090 .090 .090 .49 NITRO- GEN, NITRITE TOTAL (MG/L AS <0 0 0 0 0 0 N) .010 .010 .010 .010 .010 .010 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) •eO.OSO 0.100 0.100 0.100 0.100 1.50 NITRO- GEN, AMMONIA TOTAL (MG/L AS 0 0 0 0 0 0 N) .330 .360 .080 .030 .060 .010 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.27 0.24 0.42 0.57 0.24 0.89 E * estimate K = non-ideal count 52 RIO GUAJATACA BASIN 50011000 CANAL PRINCIPAL DE DIVERSIONBS AT LAGO DE GUAJATACA, PR--Continued WATER-QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 27... DEC 16... FEB 1993 23... APR 27.. . JUN 15... SEP 10... DATE OCT 1992 27.. . DEC 16.. . FBB 1993 23.. . APR 27.. . JUN 15... SEP 10... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.60 0.60 0.50 0.60 0.30 0.90 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) 1400 -- -- 160 -- -- NITRO- GEN, TOTAL (MQ/L AS N) 0.60 0.90 1.6 0.50 0.20 0.80 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) <5 -- -- <1 -- -- NITRO- GEN, TOTAL (MG/L AS N03) 5.3 4.0 8.9 7.1 9.3 8.9 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) 160 -- -- 100 -- -- PHOS- PHORUS ARSENIC TOTAL TOTAL (MG/L (UG/L AS P) AS AS) 0.030 <1 0.020 0.010 0.030 <1 0.030 0.010 MERCURY TOTAL SELB- RBCOV- NIUM, BRABLB TOTAL (UG/L (UG/L AS HG) AS SB) <0.10 <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- RBCOV- RECOV- ERABLE BRABLB BRABLB (UG/L (UG/L (UQ/L AS B) AS CD) AS CR) 40 <1 <1 __ __ 20 <1 <1 __ - - — — - - ZINC, TOTAL RBCOV- CYANIDE BRABLB TOTAL PHENOLS (UG/L (MG/L TOTAL AS ZN) AS CN) (UG/L) 310 <0.010 3 __ __ 10 <0.010 <1 __ __ COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) <10 -- -- <10 -- — - MBTHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 0.02 -- -- 0.03 -- -- RIO GUAJATACA BASIN 50011400 RIO GUAJATACA ABOVE MOUTH NEAR QUBBRADILLAS, PR WATER-QUALITY RECORDS LOCATIION.--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) west of Quebradillas plaza, 2.1 mi (3.4 km) upstream from Atlantic Ocean, and 6.6 mi (10.6 km) downstream from Lago Guajataca. DRAINAGE AREA.--Indeterminate PERIOD OF RECORD.--Water years 1969 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 28... DEC 28... FBB 1993 24... MAY 06... JUN 16... SEP 24... TIME 1320 0830 1240 0910 1230 0940 DIS- CHARGE, INST. CUBIC FEET PER SECOND 33 45 7.1 140 22 9.8 SPE- CIFIC CON- DUCT- ANCE (US/CM) 393 391 475 318 425 430 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.9 7.3 7.4 7.9 7.2 7.5 TEMPER- ATURE WATER (DBG C) 26.5 23.5 25.0 24.5 25.0 25.5 TUR- BID- ITY (NTU) 0.50 0.50 0.50 6.9 6.5 0.40 OXYGEN, DIS- SOLVED (MG/L) 7.2 5.8 4.4 7.8 7.2 4.4 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 105 68 53 112 89 53 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) <10 37 <10 14 <10 <10 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K140 510 200 70 K62000 220 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 380 1500 170 310 38000 2100 DATE OCT 1992 28. .. DEC 28... FBB 1993 24... MAY 06... JUN 16... SEP 24... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MG/L TOT FLD SOLVED AS MG/L AS (MG/L CACO3) CACO3 250 25 72 150 3 54 210 11 74 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS NA) 7.2 15 3.6 5.9 6.6 11 SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY SIUM, WAT WH DIS- TOT PET SULFIDB SOLVED FIELD TOTAL (MG/L MG/L AS (MG/L AS K) 0.5 1.1 0.2 1.8 0.3 2.2 CACO3 180 180 210 140 180 170 <0.5 <0.5 SULFATB DIS- SOLVED (MG/L CHLO- RIDE, DIS- SOLVED (MG/L AS S) AS SO4) AS CL) 9.4 26 8.7 9.1 6.3 18 SOLIDS, RESIDUE DATE OCT 1992 28... DEC 28... FBB 1993 24... MAY 06.. . JUN 16... SEP 24... FLUO- RIDB, DIS- SOLVED (MG/L AS F) <0.10 -- -- 0.10 -- 0.30 SILICA, DIS- SOLVED (MG/L AS SIO2) 6.6 -- — 4.2 -- 6.7 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 253 -- -- 171 -- 227 SOLIDS, DIS- SOLVED (TONS PER DAY) 22.5 -- __ 64.8 -- 6.0 TOTAL AT 105 DEG. C, SUS- PENDED (MG/L) <1 6 <1 7 20 5 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.720 1.49 2.29 2.49 1.79 0.09 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.010 0.010 0.010 0.010 0.010 0.010 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 0.720 1.50 2.30 2.50 1.80 1.00 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.020 0.220 0.010 0.030 0.010 0.020 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.18 0.68 0.19 0.27 0.19 1.8 non-ideal count 54 DATE OCT 1992 28... DEC 28... FEB 1993 24... MAY 06.. . JUN 16... SEP 24.. . DATE OCT 1992 28... DEC 28.. . FEB 1993 24... MAY 06.. . JUN 16... SEP 24... RIO GUAJATACA BASIN 50011400 RIO GUAJATACA ABOVE MOUTH NEAR QUEBRADILLAS, PR--Continued HATER-QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.20 0.90 0.20 0.30 0.20 2.0 IRON, TOTAL RECOV- ERABLE (UG/L AS FE) NITRO- GEN, TOTAL (MG/L AS N) 2.2 3.3 0.40 0.30 2.0 1.8 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS NO3) 15 12 15 10 9.7 11 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.010 0.030 0.010 0.040 0.020 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) <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 (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) <10 -- - <10 -- -- METHY- LENE BLUE ACTIVE SUB- STANCE (MG/L) 180 220 30 50 0 . 10 0.10 < 1 <1 <0.010 <0.010 0.05 0.02 55 ATLANTIC OCEAN 0146 LARES A / V is §••*«*» et ' \ SftOiES StttiP \ '-, x' EXPLANATION SURFACE-WATER STATION AND NUMBER Figure 14.-Rio Camuy basin. 56 RIO CAMOY BASIN 50014600 RIO CAMOY AT TRES PUEBLOS SINKHOLE, PR LOCATION.--Lat 18°20'42", long 66°49'29", Hydroloflic Unit 21010002, at Parque de las Cavernas del Rio Camay, 1.8 mi (2.9 km) southeast from Bscuela Segunda Unidad de Santiago Palmer, 4.7 mi (7.6 km) west from Observatorio de Arecibo and 4.8 mi (7.7 km) northeast from Plaza de Lares. DRAINAGE AREA.--Indeterminate. HATER-DISCHARGE RECORDS PERIOD OF RECORD.—June 1990 to current year. GAGB.--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, satellite telemetry at station. Gage-height and precipitation DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN AUG SEP 1 92 100 2 68 70 3 55 63 4 47 61 5 47 58 6 45 56 7 47 55 8 41 53 9 42 52 10 62 52 11 54 50 12 45 47 13 43 47 14 42 46 15 41 48 16 59 49 17 114 51 18 121 46 19 107 56 20 70 45 21 58 44 22 58 44 23 67 43 24 64 42 25 60 42 26 56 41 27 59 41 28 56 42 29 57 51 30 119 60 31 105 TOTAL 2001 1555 MEAN 64.5 51.8 MAX 121 100 MIN 41 41 STATISTICS OF MONTHLY MEAN MEAN 87.4 52.8 MAX 112 55.9 (HY) 1991 1992 MIN 64.5 50.7 (WY) 1993 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 50 43 41 42 41 46 40 39 38 38 38 37 85 99 73 43 38 37 35 34 33 33 33 32 31 33 34 32 38 49 35 1320 42.6 99 31 DATA 34.9 42.6 1993 29.8 1991 32 31 30 30 29 29 29 29 28 27 27 27 27 27 27 26 26 26 25 25 24 25 26 25 26 25 25 24 35 33 34 859 27.7 35 24 FOR HATER 25.6 27.7 1993 21.6 1991 44 33 33 30 28 27 28 27 26 25 25 25 25 24 24 23 23 23 22 24 26 23 22 e22 21 22 21 21 ___ ___ --- 717 25.6 44 21 YEARS 1990 - 23.3 27.0 1991 17.5 1992 FOR 1993 16457 45. 299 13 14 902 11. 13 73 38 19 20 20 19 18 18 18 18 17 18 18 19 24 18 16 16 16 16 15 14 14 15 14 13 13 16 14 29 29 19 70 61 645 20.8 70 13 1993 24.6 34.4 1992 18.5 1991 26 22 20 19 19 18 20 25 27 21 32 43 49 69 51 71 108 81 62 49 82 68 73 48 46 57 33 55 78 47 --- 1419 47.3 108 18 , BY HATER 44.6 47.3 1993 41.8 1992 33 31 118 116 72 84 135 106 81 69 63 58 54 52 49 84 76 59 54 55 54 65 152 94 69 65 59 73 63 96 80 2319 74.8 152 31 YEAR (WY) 76.6 80.7 1992 74.2 1991 71 58 54 51 49 48 47 51 58 51 46 58 60 48 45 44 42 41 46 48 43 41 40 39 38 38 37 37 42 49 1420 47.3 71 37 47.1 70.3 1992 32.1 1991 HATER YEAR 1 86 Sep 7 Mar 23 Mar 18 Sep 7 Sep 7 Mar 23 38 36 36 34 33 33 33 33 31 30 30 31 29 29 31 32 28 27 26 26 26 35 44 30 29 26 28 25 23 22 22 936 30.2 44 22 33.2 43.1 1991 20.7 1990 HATER 47 49 45 299 13 14 1030 12 13 84 38 19 21 21 20 19 19 19 21 19 19 22 19 20 18 17 17 31 26 20 21 26 21 19 19 18 22 39 21 33 37 55 68 767 24.7 68 17 43.8 66.0 1991 24.7 1993 YEARS 1990 - .7 .2 .1 Sep 7 Mar 23 Mar 18 Oct 31 .42 Oct 31 Mar 23 80 45 34 28 68 229 299 179 129 111 84 73 70 68 64 62 64 61 60 63 57 57 63 65 58 58 62 68 80 60 2499 83.3 299 28 66.8 83.3 1993 48.4 1992 1993 1992 1993 1993 1993 1993 1991 1991 1993 e Estimated RIO CAMUY BASIN 50014800 RIO CAMOY NEAR HAYANBY, PR 57 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 Escuela Manuel 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. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEE MAR APR MAY JUN JUL AUG SEP 1 191 193 2 139 118 3 111 99 4 89 112 5 87 92 6 79 86 7 90 82 8 76 79 9 75 78 10 105 77 11 106 76 12 79 73 13 75 81 14 72 78 15 70 74 16 88 82 17 241 81 18 234 79 19 187 83 20 99 75 21 74 101 22 72 81 23 102 73 24 94 66 25 77 64 26 68 66 27 76 101 28 74 82 29 67 149 30 214 158 31 198 —— TOTAL 3409 2739 MEAN 110 91.3 MAX 241 193 MIN 67 64 STATISTICS OF MONTHLY MEAN MEAN 208 123 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 112 77 71 78 72 67 63 57 55 53 52 51 192 298 184 89 75 70 66 64 65 69 66 64 73 114 88 95 el20 el80 e!30 2910 93.9 298 51 DATA 70.3 97.4 1988 49.7 1989 FOR elOO e90 e82 e76 e72 e68 e66 e66 e61 e58 e57 e56 e54 e54 e52 eSO eSO e52 e48 e52 e49 e52 e52 e52 eSO e47 e46 e54 e66 e62 e68 1862 60.1 100 46 FOR WATER 49.8 80.9 1988 33.1 1991 e84 e66 e58 e56 eSO e49 e48 eSO e46 45 43 42 41 39 39 38 37 37 36 40 47 38 e37 e37 e36 e35 e35 e34 ___ — - 1243 44.4 84 34 YEARS 1984 46.4 78.3 1987 29.2 1992 e34 e34 e33 e32 e33 e32 e31 e31 e32 e33 e32 49 37 34 35 33 35 34 33 32 33 33 31 31 34 32 44 79 40 166 169 1371 44.2 169 31 - 1993 47.7 66.0 1992 35.7 1991 1992 CALENDAR YEAR 33404 91. 549 25 25 187 74 29 3 Hay 23 Mar 2 Feb 29 69 e!29 76 43 39 37 38 47 68 45 59 138 128 164 135 240 286 303 195 175 348 229 236 169 154 176 106 420 307 172 —— 4731 158 420 37 116 106 349 315 155 249 358 273 177 146 123 111 101 95 95 156 152 102 105 106 131 159 357 215 149 135 117 203 151 196 191 5394 174 358 95 148 104 90 81 76 70 67 73 85 70 59 123 156 86 66 62 58 98 78 85 70 70 65 63 61 59 58 58 58 85 2382 79.4 156 58 71 69 64 58 57 57 55 55 54 53 53 52 49 47 51 54 49 46 47 46 46 61 105 66 57 52 53 47 43 40 40 1697 54.7 105 40 39 38 37 36 35 35 41 37 35 43 36 39 36 35 33 50 68 43 38 52 39 34 34 34 35 77 51 41 83 117 134 1485 47.9 134 33 165 98 62 55 123 489 893 486 247 238 148 101 87 84 74 el20 e230 e!70 e90 ellO e72 e66 e90 e!20 e96 elOO e80 e76 elSO e210 —— 5130 171 893 55 , BY WATER YEAR (WY) 112 202 1986 61.4 1990 FOR 1993 34353 94 893 31 32 2570 12 30 182 70 36 193 624 1986 43.2 1989 WATER YEAR .1 Sep 7 Mar 7 Mar 3 Sep 7 . 77 Sep 7 Mar 25 106 141 1992 79.4 1993 79.7 109 1989 54.7 1993 WATER 106 179 89 3820 25 25 6450 17 25 203 70 35 91.6 135 1989 47.9 1993 YEARS 1984 - .3 Oct 7 Apr 27 Feb 29 Oct 7 .66 Oct 7 Apr 26 153 273 1984 99.2 1992 1993 1986 1989 1985 1989 1992 1985 1985 1989 e Estimated 58 RIO CANDY BASIN 50015700 RIO CAMDY NEAR HATILLO, PR LOCATION.—Lat 18027'44", long 66049'56", Hydrologic Unit 21010002, 1.8 mi (2.9 km) southwest of Hatillo plaxa, 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, satellite telemetry at station. Gage-height and precipitation DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEE MAR APR MAY JUN JUL AUG SEP 1 269 299 2 203 158 3 131 113 4 87 189 5 83 119 6 72 101 7 86 92 8 70 87 9 68 85 10 69 88 11 156 83 12 72 79 13 67 97 14 65 160 15 61 94 16 59 100 17 270 94 18 397 87 19 380 107 20 146 88 21 90 166 22 84 134 23 142 94 24 162 82 25 103 77 26 86 82 27 92 231 28 103 165 29 85 279 30 295 363 31 355 TOTAL 4408 3993 MEAN 142 133 MAX 397 363 MIN 59 77 STATISTICS OP MONTHLY MEAN MEAN 354 187 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 INSTANTANEOUS LOW FLOW 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 247 124 108 125 161 109 98 85 80 77 74 71 105 900 445 164 124 113 104 104 99 111 107 103 105 321 182 192 263 388 165 5454 176 900 71 DATA 93.4 176 1993 51.4 1992 FOR 126 110 98 92 86 82 80 79 74 71 69 67 65 63 63 61 59 61 58 e60 e58 e62 e62 e62 e60 e56 e55 e64 e76 e72 e82 2233 72.0 126 55 FOR WATER 63.9 131 1988 46.2 1989 e96 e80 e69 e67 e61 e58 e58 59 57 55 53 53 52 50 49 48 48 47 46 52 66 51 48 48 47 46 45 44 ___ ___ --- 1553 55.5 96 44 YEARS 1984 66.7 134 1987 34.1 1992 44 44 43 41 42 41 40 40 41 42 41 55 45 40 41 40 40 38 37 35 37 35 34 34 37 35 45 79 44 231 278 1719 55.5 278 34 - 1993 67.5 88.1 1992 49.2 1988 1992 CALENDAR YEAR 47842 131 1250 31 31 303 79 34 May 23 Feb 28 Feb 28 82 144 141 56 47 41 50 117 91 56 86 209 126 187 215 304 482 588 391 331 602 580 417 359 248 341 149 1420 1850 592 — - 10302 343 1850 41 , BY WATER 207 411 1986 70.5 1992 244 199 611 1130 304 388 840 709 302 255 190 161 140 126 122 178 293 131 127 155 197 304 684 447 256 205 155 282 342 223 346 10046 324 1130 122 YEAR (WY) 386 1586 1986 59.5 1989 271 148 123 111 102 93 89 89 113 119 84 149 328 187 109 90 81 203 182 161 108 98 89 81 76 72 70 68 68 94 --- 3656 122 328 68 147 218 1992 105 1991 FOR 1993 WATER YEAR 54905 150 1850 34 35 5620 19.78 33 304 86 43 Apr 29 Mar 23 Mar 20 Apr 28 Apr 28 Mar 25 78 75 82 69 65 64 63 62 61 60 60 59 58 54 59 62 55 52 53 53 52 54 143 78 63 54 59 53 48 47 46 1941 62.6 143 46 106 161 1990 62.6 1993 WATER 168 335 129 8150 25 30 10700 24. 318 82 42 46 45 44 43 42 42 48 42 41 48 41 44 40 39 38 50 68 51 49 57 47 41 42 40 39 77 57 41 93 143 161 1699 54.8 161 38 117 180 1989 54.8 1993 YEARS 1984 - Oct 7 May 30 May 19 Oct 7 75 Oct 7 223 154 75 65 109 506 1650 1420 431 357 271 138 116 129 99 143 281 206 111 129 88 81 107 141 118 123 99 93 181 257 7901 263 1650 65 212 376 1989 117 1992 1993 1986 1992 1985 1990 1990 1985 1985 e Estimated _:-<:£? , """"^--i^'l" v v,..._ ;.-.^ ^>\ /-v — -Mac -ire-o ,= fco-Vs.-..* EXPLANATION '^J^^ -' A 0284 SURFACE-WATER STATION AND NUMBER 0205 QUALITY-OF-WATER STATION AND NUMBER V7 020050 QUALITY-OF-WATER PARTIAL RECORD v STATION AND NUMBER • 204 WELL AND WELL NUMBER • 026140 LAKE-ELEVATION STATION Figure 15.-Rio Grande de Arecibo basin. 60 RIO GRANDB DE ARBCIBO BASIN 50020100 LAGO GARZAS NEAR ADJUNTAS, PR LOCATION.—Lat 18°08'20", long 66°44'29", Hydrologic Unit 21010002, in power gate tower of Garzas Dam on Rio Vacas, 1.7 mi (2.7 km) upstream from Rio Garzas, and 2.2 mi (3.5 km) southwest of Adjuntas. DRAINAGE AREA.—15.6 mi' (40.4 km'). ELEVATION RECORDS PERIOD OF RECORD.--January 1988 to Hay 1989, March to September 1993. GAGE.--Hater-stage recorder. Datum of gage is 2,400.00 ft (731.520 m) above mean sea level. Prior to May 25, 1988 at datum 2,376.80 ft (724.449 m), May 25 to July 13, 1988 at datum 2,338.08 ft (712.647 m), July 14, 1988 to May 25, 1989 at datum 2,337.82 ft (712.560 m) above mean sea level. REMARKS.—Lake is formed by earthfill dam completed in 1943. Outflow from lake controlled by vertical-lift sluice gate and fixed-crest concrete spillway. Spillway elevation, 2,415.00 ft (736.09 m) . Lake is used for irrigation and power production. Operated by P.R. Electric Power Authorithy. Gage-height and precipitation satellite telemetry at station. EXTREMES OBSERVED FOR PERIOD OF RECORD.--Maximum elevation 2,417.66 ft (736.903 m), May 27, 1993; minimum elevation, 2,364.79 ft (720.788 m), Aug. 23, 1988. EXTREMES OBSERVED FOR WATER YEARS 1989, 1993.—Water Year 1989» Maximum elevation 2,414.76 ft (736.019 m), Jan. 23; minimum elevation, 2,365.84 ft (721.108 m), May 2. Water Year 1993t Maximum elevation 2,417.66 ft (736.903 m), May 27; minimum elevation, 2,412.26 ft (735.257 m), May 18. DAY Capacity table (based on data from Puerto Rico Electric Power Authorithy) Elevation, in feet 2,364 2,382 2,394 Contents, in acre-feet 660 1,500 2,250 Elevation, in feet 2,415 2,418 Contents, in acre-feet 4,082 4,411 ELEVATION (FEET NGVD), HATER YEAR OCTOBER 1988 TO SEPTEMBER 1989 DAILY OBSERVATION AT 24tOO VALUES OCT 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 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 NOV 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 DEC JAN MAR APR MAY JUN 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 2414.31 2414.55 2414.67 2414.72 2414.72 2414.50 2414.28 2414.07 2413.86 2413.64 2413.42 2413.20 2412.97 2412.73 2412.50 2412.25 2412.00 2411.76 2411.51 2411.24 2410.97 2410.73 2410.47 2410.20 2409.94 2409.50 A A A A A A A A A A A A A A A A A A A A A A A 2409.31 2409.43 2409.57 2410.14 2410.24 2411.30 2411.32 2411.30 2411.50 2411.71 2411.74 2411.82 2411.71 2411.77 2411.58 2411.85 2411.92 2412.12 2412.38 2412.74 2412.79 2412.73 2412.78 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 2395.91 2391.84 2391.68 2393.20 2391.69 2391.69 2391.81 2391.70 2390.98 2390.21 2389.23 2389.22 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 -- JOT, 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 AUG 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 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 MEAN MAX MIN A No gage-height record RIO GRANDS DB ARECIBO BASIN DAY 50020100 LAQO QARZAS NEAR ADJUNTAS, PR-Continued ELEVATION (FEET NGVD), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY OBSERVATION AT 24iOO VALUES OCT 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 A A A A A A A A A A A A A A A A A A A A A A A NOV 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 DEC 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 JAN 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 FEE MAR APR MAY JUN JUL AUG SEP MEAN MAX MIN 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 2414.56 2414.71 2414.76 2414.76 2414.77 2414.77 2414.78 2414.52 2414.52 2414.66 2414.76 2414.79 2414.80 2414.66 2414.77 2414.80 2414.57 2414.54 2414.53 2414.53 2414.53 2414.51 2414.52 2414.69 2414.83 2414.88 2414.80 2414.87 2414.88 2414.95 2414.82 2414.79 2414.79 2414.78 2414.78 2414.39 2414.32 2414.31 2414.47 2414.60 2414.72 2414.66 2414.88 2415.03 2414.95 2414.69 2415.03 2414.31 2414.83 2414.86 2414.96 2414.30 2414.39 2414.34 2414.43 2414.70 2414.93 2414.33 2413.75 2413.26 2413.22 2413.18 2413.17 2413.18 2412.46 2412.72 2412.75 2412.95 2413.89 2414.20 2414.51 2414.58 2414.43 2414.73 A A A A A ___ ___ ___ A A 2414.72 2414.72 2414.73 2414.71 2414.70 2414.71 2414.69 2414.63 2414.62 2414.63 2414.62 2414.61 2414.75 2414.61 2414.57 2415.04 2414.77 2414.67 2414.65 2414.63 2414.62 2414.60 2414.59 2414.58 2414.58 2414.63 2414.61 2414.62 ___ 2414.62 2414.61 2414.62 2414.58 2414.63 2414.64 2414.67 2414.60 2414.57 2414.56 2414.65 2414.58 2414.68 2414.62 2414.58 2414.57 2414.55 2414.54 2414.53 2414.51 2414.48 2414.55 2414.52 2414.58 2414.55 2414.52 2414.48 2414.67 2414.74 2414.75 2414.75 2414.60 2414.75 2414.48 2414.75 2414.67 2414.65 2414.64 2414.64 2414.64 2414.63 2414.63 2414.64 2414.63 2414.63 2414.61 2414.61 2414.61 2414.65 2414.71 2414.65 2414.63 2414.61 2414.60 2414.62 2414.75 2414.77 2414.66 2414.65 2414.66 2414.70 2414.65 2414.64 2414.63 2414.64 2414.65 2414.77 2414.60 2414.72 2414.66 2414.65 2414.65 2414.65 2414.65 2414.68 2414.67 2414.65 2414.76 2414.67 2414.66 2414.76 2414.68 2414.76 2414.80 2414.71 2414.70 2414.65 2414.67 2414.73 2414.77 2414.49 2414.57 2414.71 2414.83 2414,81 2414.84 2414.77 2414.85 2414.71 2414.85 2414.49 A NO gage-height record 62 RI° GRANDB DB ARBCIBO BASIN 50020500 RIO GRANDB DB ARECIBO NEAR ADJUNTAS, PR WATBR-QUALITY RECORDS LOCATION.--Lat 18°10'54", long 66°44'12", at Highway 135 bridge, 1.0 mi (1.6 km) upstream from Lago Adjuntas, and 1.5 mi (2.4 km) northwest of Adjuntas plaza. DRAINAGE AREA.--12.7 mi> (32.9 km') this does not include 6.0 mi> (15.6 km') above Lago Garzas. PERIOD OP RECORD.--Water years 1969-74, 1979 to current year. WATER-QUALITY DATA, WATBR YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 15... DEC 14... FEB 1993 09... APR 20. .. JUN 04. .. SBP 21... TIME 1105 0920 0945 1020 0945 1100 DIS- CHARGE, INST. CUBIC FEET PBR SECOND 76 65 18 19 41 30 SPE- CIFIC CON- DUCT- ANCE (US/CM) 276 594 330 324 270 293 PH WATBR WHOLE FIELD (STAND- ARD UNITS) 7.2 7.3 7.5 7.5 7.3 7.5 TEMPER- ATURE WATBR (DBG C) 22.0 21.0 20.0 23.5 24.0 24.5 TUR- BID- ITY (NTD) 1.9 2.6 1.0 1.3 1.8 3.0 OXYGEN, DIS- SOLVED (MG/L) 6.6 6.1 7.0 8.0 7.6 7.7 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 95 71 87 92 73 93 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 15 24 <10 23 16 <10 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K820 5700 240 380 K750 2400 STREP- TOCOCCI FECAL, (COLS. PBR 100 ML) 3400 58000 480 K1800 510 710 DATE OCT 1992 15. .. DEC 14... FBB 1993 09... APR 20. .. JUN 04... SBP 21... HARD- NESS TOTAL (MG/L AS CACO3) HARD- NESS NONCARB WH HAT TOT FLD 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) 130 30 28 14 44 100 100 27 27 7.9 20 8.5 18 SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY CHLO- SIUM, WAT 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) 2.0 3.8 0.9 2.4 0.8 2.3 CACO3 89 77 120 110 95 100 AS S) AS SO4) AS CL) <0.5 12 30 <0.5 7.0 31 10 25 SOLIDS, RESIDUE DATE OCT 1992 15... DEC 14... FBB 1993 09... APR 20... JUN 04... SBP 21.. . FLUO- RIDB, DIS- SOLVED (MG/L AS F) <0.10 -- -- 0.10 -- 0.10 SILICA, DIS- SOLVED (MG/L AS SIO2) 29 -- -- 28 -- 25 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 225 __ -- 189 -_ 176 SOLIDS, DIS- SOLVED (TONS PBR DAY) 46 — — 9.71 -- 14.0 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) <1 9 <1 1 28 13 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.880 0.590 1.06 0.850 0.720 0.880 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.030 0.010 0.040 0.050 0.080 0.020 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 0.910 0.600 1.10 0.900 0.800 0.900 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.140 0.030 0.020 0.030 0.040 0.010 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.16 0.27 0.38 0.67 0.16 0.39 K = non-ideal count RIO GRANDB DB ARBCIBO BASIN DATE OCT 1992 15... DEC 14... FBB 1993 09... APR 20... JUN 04... SEP 21... DATE OCT 1992 15... DEC 14... FBB 1993 09.. . APR 20... JUN 04... SEP 21.. . 1400 170 50020500 RIO GRANDB DB ARBCIBO NR ADJUNTAS, PR- -CONTINUED HATER QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.30 0.30 0.40 0.70 0.20 0.40 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) 1.2 0.50 0.20 0.80 0.70 0.30 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS NO3) 5.4 7.8 4.0 8.9 7.1 9.3 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.090 0.070 0.150 0.130 0.080 0.090 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 -- -- 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) <1 -- -- <1 -- -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) <10 — — 80 — -- MBTHY- LENE BLUB ACTIVE SUB- STANCE (MG/L) 160 80 <0.10 <0.10 110 <0.010 10 <0.010 0.03 0.07 64 RI° GRANDS DB ARBCIBO BASIN 50025000 RIO GRANDS DB ARBCIBO NEAR OTUADO, PR WATER-QDALITY RECORDS LOCATION.--Lat 18°18'11", long 66°41'59", at bridge near Highway 10 at km 56.4, 0.5 mi (0.8 km) downstream 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 km1 ) upstream from Lago Qarzas to Rio Guayan6s in the Rio Tallaboa basin. PERIOD OF RECORD.--Water years 1959-74, 1979 to current year. WATER-QOALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 20... DEC 14... FBB 1993 10. . . APR 16... JUN 10. . . SEP 16... TIME 1135 1115 0855 0950 0925 1120 DIS- CHARGE, INST. CUBIC FEET PER SECOND 180 168 59 184 149 79 SPE- CIFIC CON- DUCT- ANCE (US/CM) 242 194 238 180 175 250 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.1 7.2 7.6 6.9 7.0 7.4 TEMPER- ATURE WATER (DBG C) 26.5 24.0 21.0 22.0 23.5 27.0 TUR- BID- ITY (NTU) 26 6.9 3.7 4.3 250 5.3 OXYGEN, DIS- SOLVED (MG/L) 6.0 5.2 8.4 8.3 8.1 9.0 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 74 62 82 80 78 112 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) <10 34 19 <10 18 <10 COLI- FORM, FECAL, 0.45 UM-MP (COLS./ 100 ML) 5500 4600 K1800 38000 58000 3400 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 3200 K110 330 42000 41000 280 DATE OCT 1992 20... DEC 14... FBB 1993 10... APR 16. .. JUN 10... SEP 16... 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 AS CA) AS MO) AS NA) 83 9 22 100 2 33 98 6 27 6.9 12 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) 0.6 2.5 5.1 8.0 0.3 1.2 CAC03 AS S) AS S04) AS CL) 7.5 13 0.6 2.3 84 <0.5 70 94 60 <0.5 59 75 17 15 8.0 9.0 18 12 DATE OCT 1992 20. . . DEC 14... FEB 1993 10.. . APR 16... JUN 10.. . SEP 16... FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.10 -- -- 0.10 -- <0.10 SILICA, DIS- SOLVED (MG/L AS SI02) 27 -- -- 20 -- 27 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 153 -- -- 120 -- 152 SOLIDS, DIS- SOLVED (TONS PER DAY) 74.3 _- — 59.8 — 32.4 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 19 48 16 13 537 16 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 1.07 0.390 0.490 0.190 0.590 0.290 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) 1.10 0.400 0.500 0.200 0.600 0.300 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.120 0.030 0.010 0.010 0.030 0.010 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.18 0.27 0.19 0.59 0.57 0.29 K = non-ideal count RIO GRANDB DB ARECIBO BASIN 50025000 RIO GRANDB DB ARBCIBO NEAR UTOADO, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 65 DATE OCT 1992 20... DEC 14... FBB 1993 10.. . APR 16... JUN 10... SBP 16... DATE OCT 1992 20.. . DEC 14... FBB 1993 10... APR 16.. . JUN 10... SBP 16... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.30 0.30 0.20 0.60 0.60 0.30 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) 1.4 0.80 1.1 0.80 0.70 0.30 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS NO3) 6.2 4.9 3.5 5.8 4.9 3.7 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.120 0.180 0.120 0.190 0.270 0.090 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 -- -- 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- LENB BLUB ACTIVE SUB- STANCE (MG/L) 240 160 10 30 <0.10 <0.10 50 <0.010 <0.010 0.04 0.02 66 RIO GRANDE DE ARECIBO BASIN 50025155 RIO SALIENTE AT COABEY 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 Gripiflas. DRAINAGE AREA.--9.25 mi 1 (23.96 km'). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—October 1989 to current year. GAGE.--Water-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, satellite telemetry at station. Gage-height and precipitation DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 27 88 2 20 55 3 17 43 4 47 39 5 129 35 6 136 31 7 55 28 8 40 26 9 55 25 10 68 24 11 38 24 12 27 24 13 22 24 14 22 26 15 20 34 16 31 58 17 37 25 18 26 27 19 21 46 20 19 106 21 17 34 22 24 36 23 87 31 24 199 29 25 91 27 26 42 25 27 37 26 28 30 68 29 203 74 30 123 39 31 86 TOTAL 1796 1177 MEAN 57.9 39.2 MAX 203 106 MIN 17 24 AC-FT 3560 2330 CFSM 6.26 4.24 IN. 7.22 4.73 STATISTICS OF MONTHLY MEAN MEAN 42.1 27.5 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 PEAK STAGE INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 31 28 28 26 23 21 20 19 19 19 18 18 17 20 22 19 20 19 21 19 18 23 20 20 19 48 33 27 26 23 21 705 22.7 48 17 1400 2.46 2.84 DATA 14.7 22.7 1993 8.07 1992 FOR 20 20 19 19 19 20 20 17 16 16 16 16 16 16 16 15 15 14 15 14 14 15 17 16 15 14 15 65 95 29 30 664 21.4 95 14 1320 2.32 2.67 FOR WATER 22.3 48.1 1992 7.19 1990 35 23 22 19 18 17 17 16 16 16 15 15 15 15 14 16 15 14 14 17 17 13 12 12 12 12 11 11 ___ ___ --- 449 16.0 35 11 891 1.73 1.81 YEARS 1989 12.4 16.0 1993 6.00 1990 12 12 ell elO e9.6 e9.5 e9.4 el2 elO e8.8 e8.4 eS.O e8.0 e7.8 e7.6 e7.8 eS.O e8.3 8.2 13 12 8.7 8.3 8.3 8.5 8.4 8.1 7.9 7.8 7.8 7.2 282.4 9.11 13 7.2 560 .98 1.14 - 1993 10.9 13.0 1991 9.11 1993 1992 CALENDAR YEAR 11515. 31. 450 6. 7. 22840 3. 46. 61 20 10 2 5 Jan 5 6 Mar 22 6 Mar 18 40 31 6.7 6.5 6.5 14 6.3 6.2 6.2 8.3 8.2 7.4 e80 e24 elSO e60 e54 e58 e22 e!9 e!5 e!2 e!2 elO e9.4 e!6 e20 e!2 ell e210 e390 e!30--- 1390.7 46.4 390 6.2 2760 5.01 5.59 , BY WATER 25.7 46.4 1993 7.01 1990 ellO e280 e!20 e54 e35 e26 e23 e21 e24 e27 e23 e20 e!7 e33 e27 e!9 e!6 e!4 e!3 e!3 e!3 el5 e220 e98 e!60 e88 e56 56 44 130 81 1876 60.5 280 13 3720 6.54 7.54 YEAR (WY) 34.7 60.5 1993 5.35 1990 49 40 35 31 28 26 25 25 46 27 23 21 20 21 23 22 19 18 68 56 26 23 21 19 18 17 17 18 20 20 822 27.4 68 17 1630 2.96 3.31 19.7 30.4 1992 10.1 1991 FOR 1993 WATER YEAR 10850.2 29.7 390 6.2 7.2 3260 11.89 6.2 21520 3.21 43.64 57 19 8.9 Apr 29 Apr 6 Mar 28 Sep 4 Sep 4 Apr 5 16 16 24 19 16 16 31 19 16 15 79 31 34 29 19 17 16 15 15 14 14 16 16 14 13 16 14 12 11 11 11 605 19.5 79 11 1200 2.11 2.43 13.7 19.5 1993 6.85 1990 WATER 22 29 14 450 2 3 3260 11 16130 2 32 42 14 6 10 10 9.9 9.4 9.3 9.2 9.1 8.8 9.8 9.6 8.9 8.7 8.5 8.3 8.4 63 14 11 9.7 9.3 9.6 10 10 9.4 8.9 8.6 10 18 13 45 48 435.4 14.0 63 8.3 864 1.52 1.75 16.9 21.6 1992 13.8 1990 YEARS 1989 - .3 .7 .3 Jan 5 .4 Jul 23 .4 May 22 Sep 4 .89 Sep 4 .41 .71 .1 22 13 11 161 29 17 14 14 14 14 15 11 11 10 9.8 9.9 28 22 17 13 12 11 27 21 14 12 11 25 18 41 647.7 21.6 161 9.8 1280 2.33 2.60 26.0 45.2 1990 14.4 1991 1993 1993 1990 1992 1990 1990 1993 1993 e Estimated RIO GRANDE DE ARECIBO BASIN 50026050 RIO CAONILLAS ABOVE LAGO CAONILLAS NEAR JAYUYA, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°13'26", long 66<>38'22", 300 ft (91 m) off Highway 531, 700 ft (213 m) upstream from Caonillas, 3.3 mi (5.3 km) northwest of Jayuya plaza. DRAINAGE AREA.--40.4 mi* (104.6 km'). PERIOD OF RECORD.--Water years 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 67 Lago DATE OCT 1992 19... DEC 30... FEB 1993 19. .. APR 26. .. JON 02... SEP 21. .. TIME 0945 0900 0915 1010 1035 0900 DIS- CHARGE, INST. CUBIC FEET PER SECOND 115 74 27 27 176 56 SPE- CIFIC CON- DUCT- ANCE (US/CM) 175 173 209 220 173 198 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.6 8.0 7.7 7.6 7.4 7.4 TEMPER- ATURE WATER (DEG C) 22.0 21.0 21.5 25.0 24.0 23.0 TUR- BID- ITY (NTU) 23 26 1.7 7.7 5.0 31 OXYGEN, DIS- SOLVED (MG/L) 6.6 4.0 4.6 9.4 7.5 8.0 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 76 46 53 82 90 94 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 17 34 <10 <10 92 <10 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 4700 41000 200 K830 K860 3100 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 3900 25000 240 270 320 2500 DATE OCT 1992 19... DEC 30... FEB 1993 19. .. APR 26. .. JUN 02... SEP 21... HARD- NESS TOTAL (MG/L AS CACO3) HARD- NESS NONCARB WH WAT TOT FLD MG/L AS CACO3 CALCIUM DIS- SOLVED (MG/L AS CA) MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) SODIUM, DIS- SOLVED (MG/L AS NA) 76 8 20 6.3 11 86 9 23 6.9 13 78 5 20 6.8 10 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) 0.3 1.4 0.6 1.7 0.5 1.7 CACO3 AS S) AS SO4) AS CL) 98 90 76 66 57 70 <0.5 <0.5 15 15 14 14 13 11 SOLIDS, RESIDUE DATE OCT 1992 19.. . DEC 30... FEB 1993 19... APR 26... JUN 02... SEP 21.. . FLUO- RIDE, DIS- SOLVED (MG/L AS F) <0.10 -- -- 0.10 -- 0.20 SILICA, DIS- SOLVED (MG/L AS SIO2) 23 -- -- 24 -- 23 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 130 -- -- 136 -- 129 SOLIDS, DIS- SOLVED (TONS PER DAY) 40.4 — -- 9.93 — 19.4 TOTAL AT 105 DEG. C, SUS- PENDED (MG/L) 34 16 7 14 33 33 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.920 0.490 0.590 0.190 0.290 0.490 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.020 0.010 0.010 0.010 0.010 0.010 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 0.940 0.500 0.600 0.200 0.300 0.500 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.050 0.010 0.010 0.030 0.010 0.010 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.25 0.59 0.19 0.27 0.39 0.19 K = non-ideal count DATE OCT 1992 19... DEC 30... FBB 1993 19... APR 26.. . JUN 02... SEP 21... DATE OCT 1992 19.. . DEC 30... PBB 1993 19... APR 26... -TON 02... SEP 21.. . RIO GRANDS DB ARBCIBO BASIN S00260SO RIO CAONILLAS ABOVE LAOO CAONILLAS NEAR JAYUYA, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.30 0.60 0.20 0.30 0.40 0.20 IRON, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N) 1.2 1.1 0.8 0.6 1.0 1.3 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N03) S.S 4.9 3.S 3.2 5.8 4.3 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.110 0.060 0.060 0.070 0.030 0.080 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) <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 (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) <10 — — <10 — — MBTHY- LBNB BLUE ACTIVE SUB- STANCE (MG/L) 220 580 30 80 <0.10 <0.10 40 <0.010 <0.010 0.02 0.03 RIO GRANDB DB ARECIBO BASIN 50026140 LAGO CAONILLAS AT CAONILLAS, PR LOCATION.—Lat 18«16'43", long 66«39'24", Hydrologic Unit 21010001, at Lago Caonillas Dam on Rio Caonillas, 2.9 mi (4.7 km) northeast of Plaza de Utuado, 0.3 mi (0.6 km) west from Iglesia Santa Maria del Monte Carmelo, and 1.8 mi (3.0 km) northwest from Hacienda Carbonell. 69 DRAINAGE AREA.--48.4 ml* (125.4 km*). PERIOD OP RECORD. —March 1991 to current year. ELEVATION RECORDS 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 Hydroelectric Project, and provides 49,000 acre-feet (60 hm3 ) 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 OBSERVED FOR PERIOD OF RECORD. —Maximum elevation, 825.39 ft (251.58 m) , June 7, 1993; minimun elevation, less than 771.00 ft (235.00 m) , many days during water year 1991. EXTREMES OBSERVED FOR CURRENT YEAR.—Maxil (237.59 m), Mar. 13. elevation, 825.39 ft (251.58 m), June 7; minimum elevation, 779.50 ft Capacity Table (based on data from Puerto Rico Electric Power Authority) Elevation, in feet DAY 1 2 3 4 5 6 7 8 9 10 OCT 792.83 793.17 793.32 793.24 792.97 794.39 793.80 794.61 795.49 795.96 705 750 NOV 813.96 814.89 815.57 815.22 815.72 815.90 816.24 816.55 816.16 816.49 Contents, in acre-feet 0 8,421 Elevation, in feet 800 830 Contents, in acre-feet 27,982 46,161 ELEVATION (FEET NGVD), HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY OBSERVATION AT 24:00 VALUES DEC 820.15 820.38 820.60 820.83 821.03 821.22 821.40 821.24 820.36 819.78 JAN 818.06 817.98 818.03 818.22 818.20 818.09 817.48 816.67 816.82 816.74 FBB 805.18 804.68 804.04 803.09 802.11 801.47 800.92 799.78 799.23 798.72 MAR 791.93 791.74 791.20 789.99 788.70 787.36 785.94 784.60 783.64 782.91 APR 784.61 784.78 784.96 785.13 785.30 785.47 785.62 785.83 786.19 786.42 MAY 801.39 803.82 807.94 809.68 810.44 812.23 813.32 814.01 814.65 815.24 JUN A A 824.89 824.79 825.06 825.30 825.25 825.22 825.18 825.13 JUL 820.45 820.10 819.84 820.11 820.20 819.90 A A 819.43 819.15 AUG 814.87 814.25 813.66 812.61 811.42 810.34 809.62 808.88 807.60 806.29 SEP 794.97 794.28 794.42 795.08 795.85 796.32 796.31 795.98 796.04 796.23 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 795.74 796.20 796.57 796.81 796.16 796.79 798.35 799.21 799.74 800.11 799.45 799.87 800.50 802.79 803.96 804.58 805.37 805.91 808.91 810.24 811.69 816.80 817.14 817.09 817.16 817.42 817.93 817.27 816.69 816.95 816.62 817.02 817.35 817.64 817.91 818.16 818.38 818.63 819.08 819.48 819.85 819.95 820.10 820.57 821.29 821.71 821.93 822.17 822.38 822.58 822.77 822.57 821.97 821.53 820.69 820.11 819.83 820.00 819.79 819.29 818.58 818.09 815.97 815.04 814.59 814.29 813.50 812.53 812.29 812 . 07 811.19 810.22 809.21 809.34 809.46 809.56 809.67 809.12 808.06 807.48 807.70 805.62 805.98 798.09 797.47 796.90 796.99 796.84 796.35 795.77 795.18 794.53 794.25 794.05 794.09 793.90 793.16 792.25 791.60 791.70 791.78 ___ 781.47 780.70 779.93 A A 779.96 780.22 781.26 781.50 781.74 782.05 782.27 782.49 782.73 782.96 783.20 783.57 783.79 783.99 784.20 784.42 787.03 787.90 788.82 790.59 791.91 792.89 793.33 793.64 793.92 794.23 794.49 794.72 794.92 795.22 795.47 795.67 795.85 796.19 798.48 799.84 —— 815.72 816.13 A A A A A A A A A A A A A A A A A A A 824.88 824.25 824.18 824.00 823.85 823.56 823.25 822.98 823.08 823.55 823.29 822.99 822.70 822.42 822.07 821.68 821.36 821.14 820.94 820.76 —— 819.36 819.35 819.06 818.46 818.36 818.04 817.41 817.21 816.43 816.39 815.99 A A A A A A A 815.99 815.65 815.22 805.15 803.74 802.44 801.42 801.45 800.78 800.66 799.84 798.89 797.90 797.07 796.78 J96.26 794.41 794.35 793.40 793.46 793.60 793.92 794.23 794.67 796.44 796.50 796.65 796.61 796.63 796.80 796.94 796.90 797.29 797.28 796.80 796.66 795.84 796.22 796.32 796.05 795.11 795.03 795.26 795.48 —— TOTAL24768.73 24511.27 25444.89 25199.18 22324.12 —— 23729.42 MEAN 798.99 817.04 820.80 812.88 797.29 —— 790.98 MAX 811.69 819.85 822.77 818.22 805.18 —— 799.84 MIN 792.83 813.96 818.09 805.62 791.60 —— 784.61 —— 24863.96 23882.29 —— 802.06 796.08 —— 814.87 797.29 793.40 794.28 A No gage-height record 70 RIO GRANDB DE ARBCIBO BASIN 50027250 RIO GRANDB 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 Bocas and 6.6 mi (10.6 km) west of Florida plaza. DRAINAGE ARBA.--169 mi 1 (436 km1 ) does not include 6.0 mi> (15.6 km>) above Lago Garzas. PERIOD OF RECORD.--Water years 1970-71, 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 22... DEC 29... PBB 1993 10. .. APR 21... JUN 10... SEP 16... TIME 0850 0935 1000 1045 1030 1245 DIS- CHARGE, INST. CUBIC FEET PER SECOND 710 21 B800 1660 B2000 B600 SPE- CIFIC CON- DUCT- ANCE (US /CM) 179 191 209 180 181 192 PH WATER WHOLE FIELD (STAND- ARD UNITS) 6.9 7.5 7.0 6.6 6.4 4.7 TEMPER- ATURE WATER (DBG C) 26.5 23.5 24.0 24.0 26.0 27.0 TUR- BID- ITY (NTU) 36 11 8.1 120 53 13 OXYGEN, DIS- SOLVED (MG/L) 4.6 2.2 5.4 6.3 5.6 4.9 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 57 26 32 24 60 59 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) <10 31 27 27 12 <10 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 540 220 K690 200 K190 220 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 410 310 50 320 300 K160 DATE OCT 1992 22. .. DEC 29... FBB 1993 10. .. APR 21... JUN 10. .. SEP 16. .. 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, 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- TOT PET SULFIDB SOLVED FIELD TOTAL (MG/L MG/L AS (MG/L AS K) 69 7 19 5.3 8.5 0.4 2.5 60 4 16 4.8 9.6 0.5 2.5 75 10 20 6.1 9.2 0.5 2.2 CACO3 64 70 72 64 64 59 <O.S <O.S CHLO- SULFATB RIDE, DIS- DIS- SOLVED SOLVED (MG/L 11 10 12 (MG/L AS S) AS SO4) AS CL) 9.6 9.7 10 DATE OCT 1992 22... DEC 29.. . FEB 1993 10.. . APR 21... JUN 10... SBP 16... FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.10 -- -- 0.10 -- 0.10 SILICA, DIS- SOLVED (MG/L AS SIO2) 20 __ __ 18 -- 21 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 114 __ -- 109 __ 116 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 FENDED (MG/L (MG/L (MG/L (MG/L (MG/L DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) 219 490 188 13 17 12 29 16 25 0.940 0.690 0.590 0.170 0.590 0.630 0.030 0.010 0.010 0.030 0.010 0.070 0.970 0.700 0.600 0.200 0.600 0.700 0.050 0.030 0.030 0.130 0.030 0.210 0.35 0.67 0.07 0.37 0.37 0.63 B = estimate K = non-ideal count RIO GRANDS OB ARECIBO BASIN 50027250 RIO GRANDB OB ARBCIBO BELOW LAGO DOS BOCAS NEAR FLORIDA, PR--Continued WATER-QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 71 DATE OCT 1992 22... DEC 29... FEB 1993 10.. . APR 21... JUN 10... SEP 16... DATE OCT 1992 22.. . DEC 29.. . FEB 1993 10.. . APR 21. . . JUN 10.. . SEP 16... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.40 0.70 1.0 0.50 0.40 0.84 IRON, TOTAL RECOV- ERABLE (UG/L AS FE) 140 -- -- 3000 -- -- NITRO- GEN, TOTAL (MG/L AS N) 1.4 0.90 0.80 1.3 0.40 1.2 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) 7 -- -- 15 -- -- NITRO- GEN, TOTAL (MG/L AS NO3) 6.1 6.2 7.5 3.1 4.3 5.8 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) 60 -- -- 100 -- -- PHOS- PHORUS TOTAL (MG/L AS P) 0.110 0.020 0.030 0.110 0.120 0.060 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, SELE- 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) <10 -- -- 40 -- - - ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) <10 -- -- 30 -- -- CHRO- CADMIUM MIUM, COPPER, TOTAL TOTAL TOTAL RECOV- RECOV- RECOV- ERABLE BRABLE ERABLB (UG/L (UG/L (UG/L AS CD) AS CR) AS CU) <1 <1 <10 __ __ <1 4 <10 __ -— — — — — MBTHY- LENB BLUB CYANIDE ACTIVE TOTAL PHENOLS SUB- (MG/L TOTAL STANCE AS CN) (UG/L) (MG/L) <0.010 8 0.01 __ __ <0.010 2 0.03 __ __ 72 RIO QRANDB DB ARECIBO BASIN 50027750 RIO GRANDB DB ARECIBO ABOVE ARECIBO, PR LOCATION.--Lat 18°25'22", long 66°41'S8", Hydrologic Unit 21010002, 0.5 mi (0.8 Km) upstream from Rio Tanama, 3.6 mi (5.8 km) south of Arecibo and 4.9 mi (7.9 km) above mouth, and 10.4 mi (16.7 km) downstream from Lago DOB Bocas. DRAINAGE AREA.--200 mi 1 (520 km 3 ), approximately, of which an undetermined amount does not contribute directly to surface runoff. HATER-DISCHARGE RECORDS PERIOD OF RECORD.--April 1982 to current year. GAGE.--Hater-stage recorder. Elevation of gage is 30 ft (9 m), from topographic map. REMARKS.--Records fair except those for estimated daily discharges, which are poor. Flow regulated by Lago Dos Bocas Dam 10.4 mi (16.7 km) upstream from gage. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALDBS DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 486 275 2 487 723 3 431 283 4 485 503 5 552 662 6 460 741 7 639 411 8 734 91 9 772 508 10 613 522 11 525 363 12 691 414 13 414 157 14 593 97 15 694 147 16 520 57 17 111 538 18 608 572 19 607 363 20 686 478 21 522 250 22 611 134 23 422 91 24 155 420 25 77 352 26 64 84 27 264 244 28 304 192 29 203 102 30 777 283 31 579 —— TOTAL 15086 10057 MEAN 487 335 MAX 777 741 MIN 64 57 AC-FT 29920 19950 CFSM 2.43 1.68 IN. 2.81 1.87 STATISTICS OF MONTHLY MEAN MEAN 704 614 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 148 478 487 500 119 108 65 356 739 593 324 77 63 364 1330 478 625 688 329 122 424 346 275 269 584 436 423 500 616 772 616 13254 428 1330 63 26290 2.14 2.47 DATA 320 570 1988 90.3 1992 FOR 269 281 265 305 255 134 401 512 607 481 185 563 498 496 664 273 70 505 501 628 547 196 69 151 67 327 241 352 411 210 567 11031 356 664 67 21880 1.78 2.05 FOR HATER 264 437 1988 167 1989 628 733 291 532 312 256 228 664 453 472 95 102 253 249 62 195 270 299 374 188 161 123 176 363 351 205 62 47 ___ ___ 8144 291 733 47 16150 1.45 1.51 YEARS 1982 246 428 1988 111 1992 226 391 438 440 330 60 173 170 49 72 472 607 643 662 624 135 232 93 66 183 79 70 161 214 499 159 78 68 63 73 81 7611 246 662 49 15100 1.23 1.42 - 1993 228 351 1985 114 1987 1992 CALENDAR YEAR 123358 337 2030 33 50 244700 1. 22. 674 292 48 May 24 Feb 4 Feb 14 69 94 194 80 60 64 59 74 58 81 79 69 72 245 416 397 645 856 451 507 452 281 500 542 317 154 72 552 696 295 358 476 — - 9102 303 856 58 18050 1.52 1.69 265 e450 e620 e625 e490 e320 e440 ellO e390 e350 e400 e300 e!20 e200 e!20 e200 e440 e420 e300 e!40 288 608 332 292 244 e300 e490 e510 e480 e320 e220 10784 348 625 110 21390 1.74 2.01 e!60 e!45 477 372 90 174 510 462 393 461 413 117 616 519 529 260 63 121 222 311 686 603 709 129 78 174 239 467 557 243 10300 343 709 63 20430 1.72 1.92 170 58 539 275 54 162 322 321 522 110 325 455 392 472 313 295 70 45 299 609 96 202 69 45 40 40 37 519 230 158 209 7453 240 609 37 14780 1.20 1.39 164 241 514 334 453 292 155 449 101 649 763 493 766 287 60 176 423 381 373 86 67 56 254 197 733 404 250 57 50 217 306 9751 315 766 50 19340 1.57 1.81 478 444 436 87 54 225 831 617 591 652 364 74 49 170 418 263 307 337 277 147 e354 e622 e508 e342 eS6 e49 642 263 394 129 ___ 10180 339 831 49 20190 1.70 1.89 , BY HATER YEAR (WY) 408 617 1986 207 1984 FOR 1993 122753 336 1330 37 68 2800 7 243500 1 22 623 312 69 670 2000 1986 185 1989 HATER YEAR Dec 15 Jul 27 Apr 3 May 28 .51 May 28 .68 .83 393 683 1987 195 1990 277 374 1987 161 1990 HATER 408 729 279 14800 33 41 45800 18 30 295500 2 27 814 281 63 279 474 1988 154 1990 YEARS 1982 May Feb Nov May .22 May Mar .04 .71 485 1080 1984 266 1992 - 1993 1986 1992 18 1985 4 1992 23 1991 18 1985 18 1985 30 1986 e Estimated RIO GRANDB DB ARBCZBO BASIN 50028000 RIO TANAMA NEAR UTUADO, PR 73 LOCATION.--Lat 18«18'02", long 66°46'58", Hydrologlc Unit 21010001, on downstream aid* of left abutment of bridge on Highway 111, 1.2 ml (1.9 km) upstream from natural tunnel, 1.5 ml (2.4 km) northeast of Angeles, and 5.8 mi (9.3 km) northwest of Utuado. DRAINAGE AREA.--18.4 ml* (47.7 km1 ). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—June 1944 to June 1958 (dally 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 dally discharges, which are poor. DISCHARGE, CUBIC FEET PER SECOND, WATER YBAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 e!57 e82 2 e98 e64 3 e65 61 4 97 65 5 77 57 6 62 55 7 51 53 8 112 52 9 e62 51 10 345 50 11 e!09 48 12 e78 47 13 87 50 14 108 56 15 76 50 16 87 64 17 112 53 18 el!4 47 19 78 46 20 66 53 21 61 46 22 84 46 23 80 44 24 82 43 25 77 41 26 e68 40 27 e59 47 28 e54 52 29 55 44 30 126 41 31 77 TOTAL 2864 1548 MEAN 92.4 51.6 MAX 345 82 MIN 51 40 AC-FT 5680 3070 CFSM 5.02 2.80 IN. 5.79 3.13 STATISTICS OF MONTHLY MEAN MEAN 81.1 69.9 MAX 195 159 (HY) 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 39 38 43 39 44 42 36 35 34 33 33 32 59 112 64 38 35 33 34 34 33 36 34 32 31 51 40 34 35 32 30 1245 40.2 112 30 2470 2.18 2.52 DATA 43.2 121 1966 21.5 1965 FOR 29 27 27 27 26 26 27 28 25 25 25 25 25 24 25 23 22 22 22 21 21 e22 e25 e25 e24 e22 e21 e21 46 59 48 835 26.9 59 21 1660 1.46 1.69 51 30 34 27 26 25 24 23 23 22 21 22 21 21 20 23 28 21 21 29 27 22 21 20 20 20 19 19 —— 680 24.3 51 19 1350 1.32 1.37 FOR WATER YEARS 1960 29.3 50.1 1966 18.0 1974 25.1 40.5 1961 13.2 1965 20 21 19 19 19 19 20 20 24 23 24 21 19 19 23 21 20 19 18 18 17 17 16 17 21 17 37 34 19 72 33 706 22.8 72 16 1400 1.24 1.43 - 1993 24.8 71.2 1972 11.0 1984 1992 CALENDAR YBAR 16471. 45. 345 9. 11 32670 2. 33. 83 36 15 5 0 Oct 10 6 Mar 24 Mar 18 45 30 21 19 18 17 17 19 17 32 19 19 43 44 66 241 e54 37 59 41 e35 e33 e94 47 38 37 32 26 36 33 96 72 —— 1362 45.4 241 17 2700 2.47 2.75 45 77 106 61 66 60 70 54 61 53 46 42 40 38 38 58 41 37 36 38 32 31 108 51 83 91 65 119 68 91 66 1872 60.4 119 31 3710 3.28 3.78 50 45 42 40 37 36 35 35 42 39 35 38 33 30 29 30 26 25 51 40 28 26 25 24 24 23 23 22 50 35 —— 1018 33.9 51 22 2020 1.84 2.06 24 24 23 24 25 24 26 25 22 21 23 22 20 23 20 21 18 18 18 19 20 26 23 23 20 20 18 17 16 17 16 656 21.2 26 16 1300 1.15 1.33 17 17 17 17 17 26 21 17 33 28 22 20 17 16 17 62 29 22 21 19 19 19 19 17 19 19 16 72 104 56 46 861 27.8 104 16 1710 1.51 1.74 88 63 44 34 57 342 221 e!06 e71 87 68 52 52 44 40 38 37 e38 e36 e44 e36 eSO 56 43 37 38 35 37 34 31 1959 65.3 342 31 3890 3.55 3.96 , BY WATER YBAR (WY) 37.7 142 1969 9.70 1984 FOR 1993 15606 42. 345 16 17 6770 15. 30950 2. 31. 77 34 19 59.2 193 1963 12.4 1977 WATER YBAR 8 Oct 10 Mar 23 Jul 28 Oct 10 15 Oct 10 32 55 43.0 116 1979 16.5 1977 37.4 65.7 1981 19.5 1976 WATER 47. 71. 29. 2170 6. 7. 12200 17. 6. 34600 2. 35. 84 33 17 47.0 110 1979 24.3 1976 YEARS 1960 - 8 1 9 May 17 5 May 12 4 May 6 May 18 45 May 18 6 Jun 12 60 26 74.5 177 1961 27.6 1986 1993 1969 1983 1963 1984 1984 1985 1985 1977 e Estimated 74 ' * RIO GRANDE DE ARECIBO BASIN 50028000 RIO TANAMA NEAR OTUADO, PR--Continued HATER-QUALITY RECORDS PERIOD OF RECORD.—Water years 1958 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED SEDIMENT DISCHARGEi January 1968 to September 1993. 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 FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATIONSi Maximum daily mean, 20,400 mg/L November 27, 1968; minimum daily mean, 0 mg/L during water year 1985. SEDIMENT LOADSi 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 WATER YEAR 1993.— SEDIMENT CONCENTRATIONSi Maximum daily mean, 1,680 mg/L October 10, 1992; minimum daily mean, 2.0 mg/L several days. SEDIMENT LOADS: Maximum daily, 9,700 tons (8,800 tonnes) October 10, 1992; minimum daily, 0.10 ton (0.09 tonne) several days. WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 26... DEC 18... FEB 1993 25... MAY 03. .. JUN 18... SEP 22... TIME 0940 0905 0955 0955 1005 0940 DIS- CHARGE, INST. CUBIC FEET PER SECOND 63 33 19 53 26 37 SPE- CIFIC CON- DUCT- ANCE (US/CM) 156 161 166 127 185 152 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.0 7.4 7.9 6.9 7.6 7.3 TEMPER- ATURE WATER (DBG C) 23.0 19.5 19.5 22.0 23.5 22.5 TUR- BID- ITY (NTU) 14 3.2 1.2 84 2.4 4.2 OXYGEN, DIS- SOLVED (MG/L) 5.2 7.4 6.2 4.1 8.6 8.5 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 61 83 69 61 99 97 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) <10 22 <10 28 <10 <10 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K1400 310 80 K8000 K1600 K1400 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 3000 1500 260 2100 280 1600 DATE OCT 1992 26... DEC 18... FEB 1993 25... MAY 03... JUN 18... SEP 22... HARD- NESS TOTAL (MG/L AS HARD- NESS NONCARB CALCIUM WH WAT TOT FLD DIS- SOLVED MG/L AS (MG/L CACO3) CAC03 MAGNE- SIUM, SODIUM, DIS- 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- TOT PET SULFIDB SOLVED FIELD TOTAL (MG/L MG/L AS (MG/L AS K) 63 10 16 5.6 7.3 0.4 2.3 43 6 11 3.7 5.7 0.4 2.7 53 9 13 5.0 6.9 0.4 2.6 CACO3 56 54 59 56 59 78 CHLO- SULFATE RIDE, DIS- DIS- SOLVED SOLVED (MG/L <0.5 9.3 <0.5 10 12 (MG/L AS S) AS SO4) AS CL) 7.7 6.3 8.3 K « non-ideal count RIO GRANDB DE ARECIBO BASIN 75 50028000 RIO TANAMA NEAR UTOADO, PR--Continued WATER-QUALITY RECORDS SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- DATE OCT 1992 26... DEC 18... FBB 1993 25... MAY 03.. . JUN 18... SEP 22.. . DATE OCT 1992 26. . . DEC 18... FBB 1993 25... MAY 03... JUN 18... SEP 22.. . DATE OCT 1992 26.. . DEC 18... FBB 1993 25.. . MAY 03.. . JUN 18... SEP 22... RIDE, DIS- SOLVED (MG/L AS F) <0.10 -- -- 0.10 -- 0.10 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 1.0 0.50 0.70 0.50 0.80 0.90 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) 780 -- -- 1700 -- -- DIS- SOLVED (MG/L AS SI02) 26 -- -- 19 -- 23 NITRO- GEN, TOTAL (MG/L AS N) 1.3 1.1 1.3 1.3 1.5 1.4 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) 3 -- -- 2 -- -- CONSTI- TUENTS, DIS- SOLVED (MG/L) 108 -- -- 80 -- 118 NITRO- GEN, TOTAL (MG/L AS N03) 5.8 4.9 5.8 6.2 6.2 6.7 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) 60 -- -- 100 -- -- DIS- SOLVED (TONS PER DAY) 18.4 -- -- 11.5 _- 11.8 PHOS- PHORUS TOTAL (MG/L AS P) 0.020 0.040 0.030 0.020 0.020 0.030 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) <0.10 -- __ 0.10 -- -- AT 105 DBG. C, SUS- PENDED (MG/L) 14 18 <1 76 7 10 ARSENIC TOTAL (UG/L AS AS) <1 -- _- <1 _- -- SELE- NIUM, TOTAL (UG/L AS SB) <1 -- __ <1 -- -- GEN, NITRATE TOTAL (MG/L AS N) 0.290 0.590 0.590 0.790 0.590 0.490 BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 -- _- <100 -- -- SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) <1 -- __ <1 — — GEN, NITRITE TOTAL (MG/L AS N) 0.010 0.010 0.010 0.010 0.010 0.010 BORON, TOTAL RECOV- ERABLE (UG/L AS B) <10 -- -- 20 -- — — ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) 70 -- -- 10 -- -- GEN, N02+N03 TOTAL (MG/L AS N) 0.300 0.600 0.600 0.800 0.600 0.500 CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 -- — <1 -- — — CYANIDE TOTAL (MG/L AS CN) <0.010 -- -- <0.010 — — GEN, AMMONIA TOTAL (MG/L AS N) 0.010 0.040 0.010 0.020 0.030 0.010 CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) <1 -- -- 2 -- — — PHENOLS TOTAL (UG/L) 3 -- -- <1 -- -- GEN, ORGANIC TOTAL (MG/L AS N) 0.99 0.46 0.69 0.48 0.77 0.89 COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) 10 -- — 10 -- — — METHY- LBNE BLUB ACTIVE SUB- STANCE (MG/L) 0.02 -- -- 0.03 -- -- 76 RIO GRANDS DB ARBCIBO BASIN 50028000 RIO TANAMA NEAR UTUADO, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 MEAN CONCEN- SBDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) OCTOBER e!57 e98 e65 97 77 62 51 112 e62 345 e!09 e78 87 108 76 87 112 el!4 78 66 61 84 80 82 77 e68 e59 e54 55 126 77 1050 206 75 284 175 83 48 952 140 1680 232 83 135 340 153 228 314 315 150 63 17 149 162 161 145 118 59 30 23 469 143 el440 e59 el4 282 38 15 7 1380 e28 9700 e78 e!8 60 263 34 87 161 e215 35 12 2 49 47 46 34 e27 e9 e4 3 598 32 .2 .8 .6 .4 .5 MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) (CPS) (MG/L) (TONS/DAY) NOVEMBER e82 e64 61 65 57 55 53 52 51 50 48 47 50 56 50 64 53 47 46 53 46 46 44 43 41 40 47 52 44 41 ___ 178 63 26 31 31 24 15 10 9 8 8 8 26 67 64 112 98 39 22 52 22 9 9 9 7 5 45 70 67 21 ___ e55 ell 4.5 5.3 4.8 3.5 2.1 1.3 1.2 1.1 1.0 1.0 4.5 13 9.5 27 17 5.1 2.8 10 2.9 1.2 1.1 1.0 .77 .53 7.2 11 8.9 2.3 ___ DECEMBER 39 38 43 39 44 42 36 35 34 33 33 32 59 112 64 38 35 33 34 34 33 36 34 32 31 51 40 34 35 32 30 14 9 35 68 73 37 10 5 5 5 5 5 119 431 108 32 16 11 10 10 10 9 8 8 8 66 40 15 7 5 5 1.4 .90 6.2 7.2 12 4.9 .99 .53 .51 .49 .44 .43 58 357 26 3.5 1.4 .94 .90 .90 .90 .84 .72 .68 .73 15 4.7 1.4 .68 .45 .40 TOTAL 2864 14779.5 1548 217.60 1245 511.13 e Estimated RIO GRANGE DE ARECIBO BASIN 50028000 RIO TANAMA NEAR UTUADO, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 77 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 29 27 27 27 26 26 27 28 25 25 25 25 25 24 25 23 22 22 22 21 21 e22 e25 e25 e24 e22 e21 e21 46 59 48 4 5 8 11 14 13 9 6 5 6 6 6 6 6 7 7 6 6 6 7 8 8 10 59 114 74 .35 .30 .30 .29 .28 .27 .43 .64 .75 .95 .86 .59 .43 .36 .39 .38 .37 .36 .36 .42 .40 .34 .40 .40 .45 .48 .46 .55 9.8 38 21 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 51 30 34 27 26 25 24 23 23 22 21 22 21 21 20 23 28 21 21 29 27 22 21 20 20 20 19 19 82 17 9 6 5 5 4 4 4 3 3 3 3 3 3 9 21 7 7 16 12 2 2 2 3 6 12 14 18 1.4 .74 .49 .35 .34 .29 .24 .24 .19 .16 .18 .17 .16 .16 1.2 2.0 .41 .41 1.5 .87 .15 .11 .10 .15 .33 .59 .72 20 21 19 19 19 19 20 20 24 23 24 21 19 19 23 21 20 19 18 18 17 17 16 17 21 17 37 34 19 72 33 14 13 11 10 10 9 7 5 4 4 15 8 5 5 5 5 5 4 5 6 7 6 5 5 7 10 58 40 11 195 108 .75 .70 .57 .52 .52 .47 .40 .30 .25 .29 1.3 .50 .26 .26 .33 .29 .27 .23 .24 .29 .33 .27 .22 .27 .42 .48 15 5.2 .60 106 11 TOTAL 835 81.36 680 31.65 706 148.53 e Estimated 78 RIO GRANDS DB ARBCIBO BASIN 50028000 RIO TANAMA NEAR UTUADO, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 MEAN MEAN MEAN MEAN CONCBN- SEDIMENT MEAN CONCBN- SEDIMENT MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/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 21 19 18 17 17 19 17 32 19 19 43 44 66 241 eS4 37 59 41 e35 e33 e94 47 38 37 32 26 36 33 96 72 ___ APRIL 40 8 5 4 3 9 9 51 12 11 69 78 191 1030 82 29 121 100 30 15 422 61 45 37 24 16 39 34 320 145 ___ MAY 2.4 .39 .26 .20 .16 .73 .45 16 .69 .60 20 11 123 4750 el5 2.8 34 13 e3.0 el. 3 e293 9.5 7.8 5.7 2.3 1.2 6.9 3.9 249 37 ___ 45 77 106 61 66 60 70 54 61 53 46 42 40 38 38 58 41 37 36 38 32 31 108 51 83 91 65 119 68 91 66 59 252 349 92 111 103 140 45 58 54 19 13 11 9 8 81 36 13 7 5 5 5 454 90 234 275 271 583 135 306 46 8.5 93 183 17 35 24 37 7.7 11 9.4 2.3 1.5 1.1 .92 .80 25 4.6 1.2 .68 .51 .43 .43 296 15 132 139 50 682 27 205 9.2 JUNE 50 45 42 40 37 36 35 35 42 39 35 38 33 30 29 30 26 25 51 40 28 26 25 24 24 23 23 22 50 35 ___ 15 9 8 7 6 5 4 3 32 45 7 19 9 5 5 5 5 5 68 24 10 6 4 5 7 9 8 7 77 41 --- 2.1 1.1 .90 .76 .66 .53 .38 .33 6.3 5.6 .68 2.6 .91 .40 .40 .38 .34 .36 12 3.0 .76 .46 .30 .32 .47 .55 .50 .44 27 5.6 --- TOTAL 1362 5611.28 1872 2020.27 1018 76.13 e Estimated RIO GRANDE OB ARBCIBO BASIN 50028000 RIO TANAMA NEAR UTOADO, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS / DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 79 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (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 TOTAL YEAR 24 24 23 24 25 24 26 25 22 21 23 22 20 23 20 21 18 18 18 19 20 26 23 23 20 20 18 17 16 17 16 656 15606 e Estimated 12 9 10 11 11 10 15 11 4 3 3 2 2 2 2 2 2 2 2 3 4 12 10 4 5 5 5 6 7 6 5 .76 .57 .60 .66 .68 .60 1.3 .85 .26 .20 .19 .16 .10 .11 .12 .11 .10 .10 .13 .18 .20 1.1 .69 .28 .28 .25 .26 .28 .30 .29 .25 11.96 35613.51 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) AUGUST 17 17 17 17 17 26 21 17 33 28 22 20 17 16 17 62 29 22 21 19 19 19 19 17 19 19 16 72 104 56 46 5 7 9 10 10 18 10 8 55 27 16 16 12 11 9 104 29 11 8 6 5 3 2 2 8 12 6 636 432 89 63 .24 .31 .40 .46 .47 1.5 .59 .36 18 3.2 1.2 .97 .56 .50 .40 25 2.7 .68 .47 .33 .25 .15 .10 .10 .63 .67 .29 607 564 19 12 861 1262.53 MEAN DISCHARGE (CPS) 88 63 44 34 57 342 221 e!06 e71 87 68 52 52 44 40 38 37 e38 e36 e44 e36 e50 56 43 37 38 35 37 34 31 MEAN CONCEN- TRATION (MG/L) SEPTEMBER 443 104 57 32 114 1420 971 261 79 176 95 24 43 36 13 9 6 7 10 10 10 58 133 60 50 41 32 24 17 14 SEDIMENT DISCHARGE (TONS/DAY) 431 23 7.2 3.3 42 7320 2740 e92 e!8 80 20 3.4 7.3 4.5 1.3 .91 .63 e.77 e.98 el. 2 e.98 e!4 24 7.6 5.0 4.1 3.2 2.4 1.7 1.1 1959 10861.57 RIO GRANDE DE ARECIBO BASIN 50028000 RIO TANAHA NEAR UTUADO, PR--Continued HATER QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT AUG 2 SEP DATE OCT 1992 01. .. 10... APR 1993 14... AUG 28... SEP 06. .. ITB 1992 L. .. ). .. 1993 1. .. ». .. TIME 1727 1703 1730 1758 1720 SED. SUSP. FALL DIAM. PERCENT FINER THAN .016 MM 77 36 46 61 42 DIS- CHARGE, INST. CUBIC FEET PER SECOND 865 5030 4770 397 1780 SED. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM -- 45 56 79 52 SEDI- MENT, SUS- PENDED (MG/L) 5310 22800 13400 8290 12800 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 79 57 71 90 62 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 12400 310000 172000 8890 61700 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 89 69 83 96 76 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM 46 19 27 19 19 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 94 82 92 98 88 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM -- 16 32 27 25 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 98 94 97 99 96 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 61 28 36 36 33 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 99.4 99.8 99.4 100 99.8 RIO GRANDB DB ARKCIBO BASIN 50028000 RIO TANAMA NEAR UTUADO--Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT 81 DATE OCT 1992 01... 01... 08... 10... 14... 18... PEB 1993 01... APR 14... 21.. . MAY 02.. . 02... 03... 03... 06... 23.. . AUG 10... SEP 01... 06... TIME 1627 2107 1915 1803 1910 1717 1356 2055 1553 1857 2113 1550 1745 1107 1730 0806 1650 1805 STREAM- FLOW, INSTAN- TANEOUS (CFS) 237 170 241 1650 420 615 38 231 290 251 130 212 230 45 413 27 197 2820 SEDI- MENT, SUS- PENDED (MG/L) 1640 3310 4680 9570 2180 1810 101 7130 1140 821 1560 1030 1620 128 1630 381 4600 11600 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 1050 1520 3040 42600 2470 3000 10 4450 893 556 548 590 1010 16 1820 28 2450 88300 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 88 93 91 69 66 85 96 91 80 85 89 92 89 98 82 99 76 58 82 RIO GRANDS DE ARECIBO 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 bouse 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> (149.2 km1 ). WATER-DISCHARGE RECORDS PERIOD OF 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 FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 236 e!62 2 158 elSO 3 96 e!40 4 103 elSO 5 139 e!53 6 82 e!40 7 81 e!39 8 156 e!39 9 119 e!30 10 388 e!30 11 196 e!29 12 149 e!29 13 elSO e!40 14 e!71 e!70 15 e!60 e!40 16 e!60 e230 17 e240 e!80 18 e250 e!69 19 e!60 e!60 20 e!49 e220 21 e!40 e!80 22 e!65 e!70 23 e!75 e!60 24 elSO e!53 25 e!65 elSO 26 e!45 e!40 27 e!30 elSO 28 e!20 e!72 29 elSO e!40 30 e251 e!30 31 e!90 —— TOTAL 5154 4675 MEAN 166 156 MAX 388 230 MIN 81 129 AC-FT 10220 9270 CFSM 2.89 2.71 IN. 3.33 3.02 STATISTICS OF MONTHLY MEAN MEAN 170 145 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 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 e!20 ellO e!31 e!20 e!39 e!30 e!20 ellO elOO e98 e99 e93 e!60 e320 e200 ellO elOO e95 e98 elOO e94 e!08 elOO e94 e90 e!40 ellO e90 e97 e90 e86 3652 118 320 86 7240 2.05 2.36 DATA 82.0 219 1982 36.4 1989 FOR e83 e78 e78 e78 e76 e76 e80 e82 e72 e72 e72 e72 e72 e68 e72 e68 e66 e66 e66 e62 e62 e66 e74 e74 e71 e68 e64 e64 e200 e269 e!60 2631 84.9 269 62 5220 1.47 1.70 elSO ellO e!30 elOO e72 e58 e52 e48 e45 e44 42 41 41 40 40 39 50 42 40 46 55 44 40 40 40 43 42 41 ___ —— 1605 57.3 180 39 3180 1.00 1.04 FOR WATER YEARS 1969 55.3 90.8 1982 22.3 1989 45.8 85.1 1971 16.7 1989 40 42 41 39 39 40 40 40 44 42 49 56 42 41 43 42 46 42 40 40 40 41 45 46 54 49 48 88 47 104 104 1514 48.8 104 39 3000 .85 .98 - 1993 39.9 70.0 1971 16.6 1988 1992 CALENDAR YEAR 36827 101 483 29 31 73050 1.75 23.78 180 77 37 May 23 Mar 14 Mar 13 53 45 48 41 41 41 45 77 81 47 44 101 97 290 e!35 e82 e!30 e90 e80 e77 e241 e244 e84 e78 e68 e60 79 123 176 199 2997 99.9 290 41 5940 1.73 1.94 106 111 230 223 126 159 273 256 149 130 105 99 93 80 76 118 144 82 69 78 71 68 179 168 123 162 137 222 257 153 148 4395 142 273 €8 8720 2.46 2.84 107 98 103 88 76 e74 e72 e72 e74 84 66 69 99 99 65 61 56 68 101 95 63 57 54 52 50 49 48 47 55 89 2191 73.0 107 47 4350 1.27 1.42 50 48 49 45 44 43 43 49 42 40 41 47 40 42 42 42 38 37 35 35 36 44 64 40 39 40 48 37 35 34 34 1303 42.0 64 34 2580 .73 .84 35 36 36 36 36 43 43 37 35 67 38 42 36 35 36 82 69 46 43 39 37 37 39 38 35 39 36 86 153 127 73 1570 50.6 153 35 3110 .88 1.01 130 103 78 62 123 540 447 296 e!22 elSO e!20 e93 e93 e79 e70 e68 e66 111 165 129 81 80 103 96 77 87 70 77 94 71 --- 3881 129 540 62 7700 2.25 2.51 , BY WATER YEAR (WY) 73.0 141 1986 25.9 1989 FOR 1993 35568 97. 540 34 35 8010 15. 27 70550 1. 22. 170 78 40 139 371 1986 15.8 1989 WATER YEAR 4 Sep 6 Jul 30 Jul 29 Sep 6 48 Sep 6 Aug 24 69 97 88.0 179 1970 23.3 1989 68.0 120 1969 22.0 1989 WATER 88 124 51 2500 4 5 15000 17 3 64340 1 20 180 66 28 74.8 125 1991 37.4 1987 YEARS 1969 - .8 .3 Oct 7 .2 May 28 .4 May 22 May 18 .95 May 18 .3 May 28 .54 .95 115 216 1984 59.7 1986 1993 1986 1989 1985 1989 1989 1985 1985 1989 e Estimated RIO GRANDS DB ARBCIBO BASIN 50029000 RIO GRANDS DB ARBCIBO AT CENTRAL CAHBALACHB, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°27'20", long 66°42'10", Hydroloffic Unit 21010002, at bridffe on unimproved ft (152 m) upstream from Central Cambalache, near Highway 2, 8.3 mi (13.4 km) downstream Reservoir, 1.9 mi (3.1 km) downstream from Rio Tanam* , and 1.6 mi (2.6 km) southeast of DRAINAGE AREA.--200 mi' (520 km'), approximately. PERIOD OF RECORD.--Hater years 1963-66, 1969 to current year. HATER-QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 83 road, about 500 from Dos Bocas Arecibo. DATE OCT 1992 23. .. JAN 1993 04... FBB 12... APR 23... JUN 14... SEP 15. .. TIME 0745 1025 0900 0910 0945 1000 DIS- CHARGE, INST. CUBIC FEET PER SECOND B500 145 109 200 191 B500 SPE- CIFIC CON- DUCT- ANCE (US/CM) 203 301 286 224 275 225 PH HATER WHOLE FIELD (STAND- ARD UNITS) 7.1 7.1 7.7 7.1 7.3 7.0 TEMPER- ATURE HATER (DBG C) 25.5 24.0 24.0 24.0 25.0 25.8 TUR- BID- ITY (NTU) 31 2.7 3.5 140 16 8.2 OXYGEN, DIS- SOLVED (MG/L) 6.0 0.6 5.4 6.6 7.0 7.0 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 72 7 63 77 83 81 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) <10 34 <10 86 <10 31 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K820 280 490 2200 4100 K 760 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 3900 K110 360 2500 2500 340 DATE OCT 1992 23... JAN 1993 04... FBB 12. .. APR 23... JUN 14. .. SEP 15... HARD- HARD- NESS MAGNE- NESS NONCARB CALCIUM SIUM, SODIUM, TOTAL WH WAT DIS- DIS- DIS- (MG/L TOT FLD SOLVED SOLVED SOLVED AS MG/L AS (MG/L (MG/L (MG/L CACO3) CACO3 86 AS CA) AS MG) AS NA) 26 98 11 32 SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY SIUM, WAT WH DIS- SOLVED AS K) 98 30 5.1 7.5 0.4 2.1 4.3 6.8 0.3 2.4 5.5 8.6 0.4 2.3 TOT FBT SULFIDB FIELD TOTAL (MG/L MG/L AS (MG/L CAC03 110 <0.5 130 120 93 <0.5 110 82 SULFATB DIS- SOLVED (MG/L CHLO- RIDE, DIS- SOLVED (MG/L AS S) AS S04) AS CL) 9.2 8.2 9.7 8.5 11 10 SOLIDS, RESIDUE DATE OCT 1992 23... JAN 1993 04... FBB 12... APR 23.. . JUN 14... SEP 15.. . FLUO- RIDB, DIS- SOLVED (MG/L AS F) <0.10 -- -- 0.10 -- <0.10 SILICA, DIS- SOLVED (MG/L AS SIO2) 19 -- -- 13 -- 18 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 144 -- -- 133 -- 141 SOLIDS, DIS- SOLVED (TONS PER DAY) -- -- — 71.6 -- -- TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 5 41 9 57 22 15 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.700 0.690 0.490 0.430 0.390 0.690 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.010 0.010 0.010 0.080 0.010 0.010 NITRO- GEN, N02+NO3 TOTAL (MG/L AS N) 0.710 0.700 0.500 0.500 0.400 0.700 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.030 0.020 0.010 0.080 0.010 0.020 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.17 0.58 0.29 0.52 0.59 1.6 B = estimate K = non-ideal count 84 RIO GRANDB DB ARBCIBO BASIN 50029000 RIO GRANDB DB ARECIBO AT CENTRAL CAMBALACHB, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 23... JAN 1993 04... FBB 12... APR 23... JUN 14... SEP 15.. . 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 (OG/L AS CR) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) 0.20 0.60 0.30 0.60 0.60 1.6 0.91 1.3 0.80 1.0 1.1 2.3 4.0 5.8 3.5 6.8 4.7 10 0.060 0.030 0.030 0.120 0.030 0.030 <100 <100 20 DATE OCT 1992 23... JAN 1993 04.. . FEB 12... APR 23.. . JUN 14... SEP 15... 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 (OG/L AS HG) SELE- NIUM, TOTAL (UG/L AS SB) SILVER, TOTAL RECOV- ERABLE (OG/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) 490 1400 60 80 <0.10 <0.10 30 20 <0.01 <0.01 <0.01 <0.01 PESTICIDE ANALYSES DATE JUN 1993 26.. . TIME 0945 PCS, TOTAL (UG/L) CHLOR- ALDRIN, DANE, <0.010 ODD, DDE, DI- DI- ENDO- DDT, AZINON, BLDRIN SULFAN, TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL TOTAL (UG/L) (OG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) (UG/L) <0.010 <0.010 <0.010 <0.01 <0.010 <0.010 DATE JUN 1993 26.. . ENDRIN WATER UNFLTRD BTHION, REC TOTAL (OG/L) (OG/L) HBPTA- 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) <0.01 MBTH- OXY- CHLOR, TOTAL (UG/L) <0.01 METHYL PARA- THION, TOTAL (UG/L) MIRBX, TOTAL (UG/L) <0.01 <0.01 DATE JUN 1993 26... PARA- THION, TOTAL (UG/L) <0.01 NAPH- THA- LENES, POLY- CHLOR. TOTAL (UG/L) <0.10 PER- TOTAL (UG/L) TOX- THANE APHENE, TOTAL (UG/L) TOTAL TRI- THION (UG/L) <0.01 2,4-D, 2,4,5-T 2, 4-DP SILVBX, TOTAL (UG/L) <0.01 TOTAL (UG/L) <0.01 TOTAL (UG/L) <0.01 TOTAL (UG/L) <0.01 ATLANTIC Jcv-v / 032290 KJ , , 'i.cjf0''»/ Inland ^ ,*w»»oj ci¥sd« . -^* J Rio l-satttfo Bsit:?> /' J,Mu*5E75--s*7?«jte- «»j«*«?^. ' /*8»*-* ^_,^ EXPLANATION A 0350 SURFACE-WATER STATION AND NUMBER T0307 QUALITY-OF-WATER STATION AND NUMBER • 21° 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 16°13'25*, long 66<>23'34", Hydrologic Unit 21010001, on right bank, 0.4 mi (0.6 km) south of junction of Highways 155 and 156 in Orocovis, 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 km>) . WATER-DISCHARGE RECORDS PERIOD OF RECORD.—April 1981 to September 1982, October 1988 to current year. GAGE.—Water-stage recorder. Elevation of gage if 500 ft (152 m), from topographic map. REMARKS.—Record* poor. Low flow affected by diversions for water supply. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL ADO SEP 1 e.70 1.1 2 e.30 .75 3 e.30 11 4 e.20 8.1 5 e9 . 0 4.7 6 54 1.7 7 6.9 1.2 8 1.5 .85 9 .72 .71 10 .40 .57 11 .26 .44 12 .23 .47 13 .21 .38 14 .42 .35 15 .63 .33 16 .29 .52 17 .28 .47 18 5.3 .35 19 2.7 .34 20 .70 3.6 21 .27 1.4 22 .40 4.7 23 43 5.1 24 16 1.8 25 7.8 .91 26 2.3 .58 27 17 7.1 28 9.1 67 29 6.1 71 30 6.2 31 31 2.3 TOTAL 195.51 228.52 MEAN 6.31 7.62 MAX 54 71 MIN .20 .33 AC-FT 388 453 CFSM 1.25 1.51 IN. 1.45 1.69 8.6 5.3 3.3 2.0 1.4 1.2 1.0 1.1 .92 .76 .74 .94 .97 12 9.2 3.5 3.2 2.3 1.9 2.0 1.7 2.9 2.3 3.1 2.9 51 21 8.8 5.6 4.1 3.0 168.73 5.44 51 .74 335 1.08 1.25 STATISTICS OF MONTHLY MEAN DATA MEAN 22.9 7.69 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 6.59 15.8 1982 1.69 1989 FOR 2.3 1.8 1.9 1.7 1.5 1.5 4.8 2.6 1.7 1.4 1.3 1.5 1.4 1.4 .95 .88 .73 .83 .75 .88 .67 1.2 1.7 .67 .79 .60 .90 5.5 14 2.4 4.5 64.75 2.09 14 .60 128 .42 .48 3.4 1.3 2.5 1.3 el.l el.O .74 .70 .80 .60 .64 .74 .70 el.O e.98 el. 7 2.7 1.9 1.2 7.8 5.4 2.2 2.8 1.5 1.2 1.2 1.0 1.0 ___ —— 49.10 1.75 7.8 .60 97 .35 .36 FOR WATER YEARS 1981 7.90 34.3 1992 1.47 1989 2.38 2.97 1992 1.75 1993 1.1 1.4 1.1 1.3 1.4 1.4 1.5 .93 1.1 1.1 1.1 .89 .85 .98 .92 1.4 1.4 1.7 1.3 1.4 1.4 1.5 1.7 1.4 2.1 1.4 1.6 1.3 1.3 1.2 1.2 40.37 1.30 2.1 .85 80 .26 .30 - 1993 1.86 2.46 1990 1.30 1993 1992 CALENDAR YEAR 3749.42 10.2 415 .20 .33 7440 2.04 27.73 17 2.1 .86 Jan 5 Oct 4 Oct 11 1.3 1.1 .91 1.1 1.5 1.8 1.7 6.3 2.4 2.5 6.5 7.2 61 23 31 18 13 5.1 e2.0 e2.0 el. 7 el. 8 el. 2 e5.0 e3.0 el. 7 el. 4 119 229 77 —— 630.21 21.0 229 .91 1250 4.18 4.66 37 121 57 21 13 10 9.2 8.4 9.7 8.6 7.9 7.3 6.6 13 8.2 6.6 5.1 5.0 3.9 4.6 4.8 4.7 99 32 25 21 13 9.7 8.2 7.4 6.8 594.7 19.2 121 3.9 1180 3.81 4.40 7.1 5.7 5.6 5.0 4.7 4.2 3.9 6.4 4.9 4.6 3.5 3.6 3.2 3.9 4.2 3.9 2.3 2.3 24 21 7.4 5.6 4.4 4.6 3.8 3.7 3.8 4.2 3.9 4.1 169.5 5.65 24 2.3 336 1.12 1.25 4.0 3.6 3.6 4.8 3.8 3.6 3.2 3.3 2.5 2.7 16 9.8 7.6 9.7 4.4 3.6 3.3 3.8 4.3 3.7 2.1 4.4 5.3 5.5 3.3 3.0 3.2 2.4 2.2 2.0 1.7 136.4 4.40 16 1.7 271 .87 1.01 1.5 1.8 1.5 1.3 1.6 1.2 1.2 1.5 1.9 1.8 2.5 1.6 1.4 1.0 1.6 24 5.4 2.5 2.2 1.7 1.7 1.8 8.3 2.0 1.6 1.3 1.4 2.6 2.5 1.6 1.5 85.5 2.76 24 1.0 170 .55 .63 1.1 1.3 1.4 24 25 26 16 4.1 2.5 2.5 2.0 2.8 1.6 2.1 1.6 1.3 9.0 1.8 .93 1.0 .91 .96 5.6 4.6 1.0 .91 .86 8.2 3.5 1.0 155.57 5.19 26 .86 309 1.03 1.15 , BY WATER YEAR (WY) 7.12 21.0 1993 1.32 1982 FOR 1993 2518 6 229 1570 10 5000 1 18 13 2 14.5 31.8 1981 1.42 1989 5.44 15.2 1992 1.16 1982 WATER YEAR .86 .90 .20 .33 .38 .37 .63 .1 .74 Apr 29 Oct 4 Oct 11 Apr 29 Apr 29 3.76 8.40 1991 1.45 1982 WATER 7 9 6 420 2320 11 5670 1 21 13 2 1 4.48 12.3 1989 1.03 1982 YEARS 1981 .82 .35 .17 Sep .20 Oct .33 Oct Jan .53 Jan .56 .13 .2 .1 12.2 39.6 1989 1.72 1992 - 1993 1992 1982 18 1989 4 1992 11 1992 5 1992 5 1992 e Estimated RIO GRANDB OB 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 1.0 mi (1.6 km) north of Orocovis plaza. DRAINAGE AREA.--10.1 mi' (26.2 km'). PERIOD OF RBCORD.--Water year 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 87 568, DATE OCT 1992 15... DEC 02... FEB 1993 18... APR 22... JUN 11... SEP 17... TIME 0850 0840 1120 0905 1115 1300 HARD- NESS TOTAL (MG/L DIS- CHARGE, INST. CUBIC FEET PER SECOND 9.4 18 8.8 7.9 11 6.0 HARD- NESS NONCARB WH WAT TOT FLD SPE- CIFIC CON- DUCT- ANCE (US/CM) 313 238 270 313 283 287 CALCIUM DIS- SOLVED PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.9 6.7 8.2 7.7 8.0 7.8 MAGNE- SIUM, DIS- SOLVED TEMPER- ATURE WATER (DBG C) 22.0 22.0 22.0 21.0 24.5 25.5 SODIUM, DIS- SOLVED TUR- BID- ITY (NTU) 16 84 7.6 46 32 1.8 SODIUM AD- SORP- TION OXYGEN, DIS- SOLVED (MG/L) 5.9 5.0 7.0 7.5 7.5 8.3 POTAS- SIUM, DIS- SOLVED OXYGEN, OXYGEN DIS- DEMAND, SOLVED CHBM- (PER- ICAL CENT (HIGH SATUR- LEVEL) ATION) (MG/L) 72 11 60 <10 83 <10 92 10 99 <10 105 <10 ALKA- LINITY WAT WH TOT FBT SULFIDB FIELD TOTAL COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 3400 2100 2500 K1700 3000 1200 SULPATB DIS- SOLVED STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 2400 3900 K180 3400 280 660 CHLO- RIDE, DIS- SOLVED DATE OCT 1992 15. .. DEC 02... FEB 1993 18. .. APR 22. .. JUN 11... SEP 17... AS CACO3) CAC03 MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L AS CA) AS MG) AS NA) AS K) 120 2 28 11 12 140 12 35 12 14 120 5 30 10 12 0.5 1.7 0.5 1.8 0.5 1.8 CACO3 130 98 130 130 95 100 <0.5 <0.5 11 11 11 (MG/L AS S) AS S04) AS CL) 10 14 15 DATE OCT 1992 15... DEC 02... FEB 1993 18... APR 22... JUN 11.. . SEP 17... FLUO- RIDE, DIS- SOLVED (MG/L AS F) 0.10 -- -- 0.10 -- 0.10 SILICA, DIS- SOLVED (MG/L AS SIO2) 31 — -- 34 -- 35 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 172 -- -- 200 -- 175 SOLIDS, DIS- SOLVED (TONS PER DAY) 4.36 -- -- 4.26 -- 2.83 RESIDUE TOTAL AT 105 DEG. C, SUS- PENDED (MG/L) 8 27 8 45 <1 13 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.970 1.39 0.990 1.18 1.06 0.75 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.030 0.010 0.010 0.020 0.040 0.050 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 1.00 1.40 1.00 1.20 1.10 0.800 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.060 0.030 0.010 0.010 0.080 0.120 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.44 0.47 0.49 0.92 0.92 1.2 non-ideal count aa RIO GRANDE DE MANATI BASIN 50030700 RIO OROCOVIS NEAR OROCOVIS, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 15... DEC 02... FEE 1993 18.. . APR 22... •TON 11... SEP 17... DATE OCT 1992 15... DEC 02.. . FBB 1993 18... APR 22r. . iTON SEP 17.. . NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.50 0.50 0.20 0.50 1.0 1.2 IRON, TOTAL RECOV- ERABLE (UG/L AS FE) 390 -- -- 1300 -- NITRO- GEN, TOTAL (MG/L AS N) 1.9 2.1 1.2 1.7 2.4 1.5 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) 5 -- -- <1 -- NITRO- GEN, TOTAL (MG/L AS NO3) 8.4 9.3 8.4 7.5 9.5 9.0 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) 50 -- -- 80 -- PHOS- PHORUS ARSENIC TOTAL TOTAL (MG/L (UG/L AS P) AS AS) 0.200 <1 0.210 0.150 0.160 <1 0.130 0.180 MERCURY TOTAL SELB- RBCOV- NIUM, BRABLE TOTAL (UG/L (UG/L AS HG) AS SB) <0.10 <1 -- __ <0.10 <1 __ BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 -- __ <100 -- - - SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) <1 __ -- <1 -- BORON, TOTAL RECOV- ERABLE (UG/L AS B) <10 -- -- 40 -- " ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) 70 -- -- 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 RECOV- RECOV- ERABLE BRABLE (UG/L (OG/L AS CR) AS CU) <1 <10 __ __ <1 <10 __ .. MBTHY- LBNE BLUB ACTIVE PHENOLS SUB- TOTAL STANCE (UG/L) (MG/L) <1 0.02 __ __ <1 0.03 __ RZO ORANDE DB MANATZ BASZN " 50031200 RZO GRANDE DB MANATZ NEAR MOROVIS, PR LOCATION.--Lat 18°17'45", long 66°24'47", Hydrologic Unit 21010001, on right bank , 0.1 mi (0.2 km) downstream from Quebrada Perchas, 0.8 mi (1.3 km) upstream from Rio Sana Huerto, and 2.2 mi (3.5 km) south of Morovis. DRAINAGE AREA.--S5.2 mi' (143.0 km'). WATER-DISCHARGE RECORDS PERZOD OF RECORD.—January 1965 to current year. 6A6B.—Water-stage recorder and concrete control. Elevation of gage is 440 ft (134 m), from topographic map. Feb. 2, 1966 to Apr. 27, 1967, itaff gage read twice daily. REMARKS.--Record! fair except those for estimated daily discharge*, which are poor. Public water-supply pumpage, about 300 ft (91 m) above the station, influence! low-flow discharges. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEE MAR APR MAY JON JUL ADG SEP 1 97 39 2 56 35 3 33 51 4 106 156 5 305 133 6 284 74 7 154 56 8 75 45 9 48 43 10 41 39 11 60 36 12 32 55 13 25 102 14 24 65 15 29 45 16 41 54 17 171 67 18 275 54 19 187 48 20 101 47 21 55 61 22 S3 95 23 104 156 24 158 104 25 169 76 26 90 60 27 56 169 28 69 290 29 62 196 30 93 182 31 50 TOTAL 3103 2633 MEAN 100 87.8 MAX 305 290 MIN 24 35 AC-FT 6150 5220 CFSM 1.81 1.59 IN. 2.09 1.77 STATISTICS OF MONTHLY MEAN MEAN 165 155 MAX 1037 491 (HY) 1971 1971 MIN 24.0 28.3 (HY) 1978 1974 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOWEST ANNUAL MEAN HIGHEST DAZLY MEAN LOWEST DAZLY 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 116 91 66 55 47 44 39 35 35 33 31 28 28 105 213 93 88 85 70 58 49 81 89 93 101 492 270 175 142 119 101 3072 99.1 492 28 6090 1.80 2.07 DATA 117 522 1966 27.9 1984 FOR 87 76 74 76 66 69 126 141 91 76 67 66 61 58 54 51 SO 47 44 44 43 50 78 51 48 45 42 44 181 99 128 2233 72.0 181 42 4430 1.30 1.50 FOR HATER 83.5 191 1992 24.7 1984 176 85 78 63 56 49 46 43 41 39 38 39 40 36 35 42 63 42 37 47 71 51 41 40 37 37 36 34 ___ --- 1442 51. 5 176 34 2860 .93 .97 YEARS 1965 65.9 179 1969 23.4 1984 34 38 35 32 31 32 31 32 32 32 28 29 29 28 28 42 51 41 33 33 31 30 35 36 29 25 25 22 20 30 33 987 31.8 51 20 1960 .58 .67 - 1993 69.1 226 1972 12.7 1984 1992 CALENDAR YEAR 32289 88. 2480 17 20 64050 1. 21. 170 48 26 2 Jan 5 Sep 28 Sep 11 60 76 21 21 20 19 19 18 18 109 165 160 322 238 383 436 356 304 241 180 127 151 189 165 107 87 93 74 68 203 949 506 --- 5749 192 949 18 11400 3.47 3.87 530 730 402 207 173 160 146 185 490 220 178 155 138 153 137 124 117 111 106 104 102 106 270 189 169 178 137 120 115 108 104 6164 199 730 102 12230 3.60 4.15 93 89 85 81 75 74 70 74 78 74 65 63 61 59 58 66 54 52 110 169 94 78 66 60 57 S3 51 52 56 80 2197 73.2 169 51 4360 1.33 1.48 S3 SO 57 59 49 47 48 59 46 45 143 ISO 79 102 68 58 54 49 47 48 47 80 125 128 108 85 76 60 54 S3 S3 2180 70.3 150 45 4320 1.27 1.47 SO SO 47 44 44 45 43 40 40 40 42 41 38 36 37 202 133 64 SO 44 39 41 67 43 37 37 36 47 64 67 55 1663 53.6 202 36 3300 .97 1.12 40 37 34 82 102 211 185 139 72 56 S3 43 39 38 43 65 194 227 255 141 78 58 e92 176 81 68 79 99 88 66 2941 98.0 255 34 5830 1.78 1.98 , BY HATER YEAR (WY) 117 412 1969 10.6 1984 FOR 1993 34364 94 949 18 19 6040 6 17 68160 1 23 181 61 33 171 915 1985 23.6 1977 HATER YEAR .1 Apr 29 Apr 6 Apr 1 Apr 29 .56 Apr 29 Mar 30 .71 .16 65.5 173 1987 16.9 1977 49.2 157 1979 18.5 1977 HATER 102 248 40 17100 5 6 48000 17 4 73670 1 25 179 51 24 58.8 435 1979 9.70 1984 YEARS 1965 - .3 May 18 .7 Aug 20 .8 Aug 18 May 18 .89 May 18 .4 Apr 15 .84 .03 93.4 386 1979 25.0 1977 1993 1971 1974 1985 1984 1984 1985 1985 1984 e Estimated 'V RIO GRANDB DB MANATI BASIN 50031200 RIO GRANDB DB MANATI NEAR MOROVIS, PR--Continued HATBR-QUALITY RECORDS PERIOD OF RECORD.--Hater years 1968 to current year. HATER-QUALITY DATA, HATBR YEAR OCTOBER 1992 TO SBPTBMBBR 1993 DATB OCT 1992 15... DBC 02. .. FBB 1993 18. .. APR 22. .. JUN 11. .. SBP 23. .. DATB OCT 1992 15... DBC 02... FBB 1993 18. .. APR 22. .. JUN 11. .. SBP 23... TIME 1105 1050 0945 1050 0930 0945 HARD- NESS TOTAL (MG/L AS CAC03) 88 -- -- 86 -- 100 DIS- CHARGE, INST. CUBIC FEET PBR SECOND 27 93 41 130 65 47 HARD- NESS NONCARB WH HAT TOT FLD MG/L AS CACO3 8 -- -- 10 -- 15 SPE- CIFIC CON- DUCT- ANCE (US/CM) 269 245 265 220 262 257 CALCIUM DIS- SOLVED (MG/L AS CA) 21 -- -- 20 -- 25 PH HATER WHOLE FIELD (STAND- ARD UNITS) 7.8 6.7 7.7 7.4 7.7 7.7 MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) 8.7 -- -- 8.8 -- 10 TEMPER- ATURE WATBR (DBG C) 27.0 24.0 22.0 24.0 25.5 25.5 SODIUM, DIS- SOLVED (MG/L AS NA) 11 -- __ 12 -- 11 TUR- BID- ITY (NTU) 6.4 72 23 100 2.0 6.5 SODIUM AD- SORP- TION RATIO 0.5 -- _- 0.6 -- 0.5 OXYGEN, DIS- SOLVED (MG/L) 6.4 6.0 6.8 8.8 8.5 6.8 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 2.0 -- -- 2.1 -- 2.5 OXYGEN, OXYGEN DIS- DEMAND, SOLVED CHBM- (PBR- ICAL CENT (HIGH SATUR- LEVEL) ATION) (MG/L) 80 11 71 12 77 <10 104 13 103 <10 82 <10 ALKA- LINITY WAT WH TOT FBT SULFIDB FIELD TOTAL MG/L AS (MG/L CACO3 AS S) 120 <O.S 98 100 78 <0.5 98 110 COLI- FORM, FECAL, 0.45 UM-MP (COLS./ 100 ML) K190 580 1800 K8000 K620 1000 SULFATB DIS- SOLVED (MG/L AS SO4) 11 -- -- 9.0 -- 9.S STREP- TOCOCCI FECAL, (COLS. PBR 100 ML) K140 1800 710 13000 K60000 200 CHLO- RIDE, DIS- SOLVED (MG/L AS CL) 12 -- -- 13 — 14 SOLIDS, RESIDUE DATB OCT 1992 15... DBC 02.. . FBB 1993 18.. . APR 22.. . JUN 11.. . SBP 23... FLUO- RIDB, DIS- SOLVED (MG/L AS F) <0.10 -- -- <0.10 -- 0.10 SILICA, DIS- SOLVED (MG/L AS SI 02) 26 -- -- 25 -- 27 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 145 -- -- 137 -- 165 SOLIDS, DIS- SOLVED (TONS PBR DAY) 10.6 — — 48.0 — 20.9 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 3 67 25 135 3 19 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.580 0.490 1.67 1.27 0.96 0.76 NITRO- GBN, NITRITE TOTAL (MG/L AS N) 0.020 0.010 0.030 0.030 0.040 0.760 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 0.600 0.500 1.70 1.30 1.00 0.040 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.070 0.010 0.060 0.050 0.080 0.800 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.33 0.19 1.4 0.85 1.3 1.5 K = non-ideal count RIO GRANDE DE MANATI BASIN 91 50031200 RIO GRANDE DE MANATI NEAR MOROVIS, PR—Continued WATER- QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 15... DEC 02... FEB 1993 18... APR 22... JUN 11... SEP 23... DATE OCT 1992 15.. . DEC 02.. . FEB 1993 18... APR 22... JUN 11.. . SEP 23... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.40 0.20 1.5 0.90 1.4 1.6 IRON, TOTAL RECOV- ERABLE (UG/L AS FE) NITRO- GEN, TOTAL (MG/L AS N) 1.0 0.70 3.2 2.2 2.4 8.9 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS NO3) 4.4 6.8 14 9.7 5.4 7.2 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.070 0.050 0.090 0.080 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 (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 (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) 10 — — 10 — -- METHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 1800 3900 60 170 <0.10 <0.10 20 <0.010 10 <0.010 0.01 0.01 92 RIO QRANDE DB HANATI BASIN 50032290 LAGO EL GUINBO AT DAMSITE, PR LOCATION.--Lat 18°09'41", long 66°31'36", 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 limlta between the Municipality of Ciales and Orocovia. DRAINAGE AREA. —1. 64 mi> (4.25 km» ). PERIOD OF RECORD.—May 1988 to current year. ELEVATION RECORDS GAGE.—Water-stage recorder. Datum of gage ia mean aea level. REMARKS.--Lago Quineo waa completed in 1931. It provide* a maximum storage of approximately 2,180 ac-ft (2.688 hm3 ) for power and irrigation. Watera are discharged through an outlet power tunnel into the Rio Toro Negro and coveyed to the head water worka of Toro Negro Hydroelectric Plant No.2, for energy generation at Toro Negro Hydroelectric plant No.l, and are discharged into the Quayaba1 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 ft5/a. 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, 2,961.21 ft (902.58 m), Oct. 23; minimun elevation, 2,936.10 ft (894.92 m), Sept. 4. 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 ELEVATION (FEET NGVD), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY OBSERVATION AT 24:00 VALUES DAY OCT NOV DEC JAN FEE 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 2952.02 2952.18 2952.32 2953.31 2954.01 2955.82 2956.77 2957.25 2958.99 2959.51 2959.87 2960.17 2960.40 2960.63 2960.70 2960.72 2960.73 2960.69 2960.69 2960.69 2960.69 2960.74 2960.82 2960.87 2960.72 2960.71 2960.70 2960.70 2960.78 2960.72 2960.76 2958.89 2960.87 2952.02 2960.76 2960.72 2960.72 2960.72 2960.71 2960.71 2960.71 2960.71 2960.71 2960.70 2960.70 2960.69 2960.73 2960.75 2960.69 2960.78 2960.38 2960.08 2959.78 2960.72 2960.30 2960.60 2960.20 2959.80 2959.80 2960.01 2960.21 2960.13 2960.81 2960.25 2960.49 2960.81 2959.78 2959.95 2959.58 2959.25 2958.87 2958.47 2958.67 2958.21 A A A A A A A A A 2955.55 2955.67 2955.81 2955.95 2956.07 2956.23 2956.35 2956.04 2956.18 2955.95 2956.09 2955.68 2955.50 2955.10 2954.99 -__ ___ ___ 2955.10 2955.24 2955.36 2955.00 2954.80 2954.90 2954.99 2955.07 2955.15 2955.23 2955.31 2954.91 2954.97 2955.09 2955.16 2954.95 2954.47 2954.53 2954.08 2954.16 2954.24 2954.34 2953.86 2953.92 2953.98 2954.04 2954.14 2955.34 2956.39 2956.08 2955.87 2954.86 2956.39 2953.86 2955.61 2955.77 2955.91 2956.03 2956.12 2956.22 2956.30 2956.40 2956.48 2956.56 2956.64 2956.74 2956.28 2956.36 2956.42 2956.54 2956.62 2956.68 2956.74 2956.02 2956.10 2956.16 2956.22 2956.29 2956.01 2955.97 2956.02 2956.07 — - 2956.26 2956.74 2955.61 2956.13 2956.17 2956.20 2956.25 2956.29 2956.32 2956.35 2956.40 2956.41 2956.31 2956.35 2956.39 2956.42 2956.46 2956.52 2956.56 2956.58 2956.62 2956.64 2956.69 2956.72 2956.75 2956.67 2956.71 2956.75 2956.79 2956.83 2956.85 2956.88 2956.70 2956.71 2956.53 2956.88 2956.13 2956.54 2956.34 2956.36 2956.39 2956.24 2956.08 2956.09 2955.89 2955.91 2956.03 2956.13 2956.04 2956.49 2956.50 2956.39 2956.45 2956.72 2956.89 2957.06 2957.12 2957.53 2957.64 2957.70 2957.77 2957.82 2957.65 2957.70 2958.45 2959.57 2959.96 --- 2956.98 2959.96 2955.89 2960.23 2960.45 2960.63 2960.56 2960.53 2960.55 2960.44 2960.55 2960.78 2960.70 2960.68 2960.47 2960.19 2960.24 2959.92 2959.75 2959.30 2958.88 2958.44 2958.22 2959.28 2959.21 2960.28 2960.20 2960.16 2960.73 2960.57 2960.28 A A A ... ___ A 2960.18 2959.99 2959.56 2958.80 2959.00 2958.72 2958.55 2958.46 A A A A A A A A A A A A A A 2956.39 2956.10 2955.73 2955.87 2955.74 2955.39 2955.00 ___ ___ 2954.59 2954.21 2954.06 2954.21 2954.34 2953.94 2953.53 2953.11 2952.57 2952.07 2952.80 2952.49 A A A 2952.18 2951.78 2951.91 2951.35 2950.89 2950.39 2950.09 2949.69 2948.75 A A A 2948.33 2947.82 2947.20 2947.31 ___ ___ ___ 2947.40 2946.46 2945.16 2944.25 2943.26 2942.86 2942.30 2942.39 A 2940.93 2940.52 2940.00 2939.19 A A A A 2939.68 2939.29 2939.22 2938.51 2938.63 2938.24 2937.81 2937.44 2936.92 2936.88 2937.63 2937.86 2937.71 2937.49 ___ ___ ___ 2937.32 2936.97 2936.67 2937.87 2938.24 2938.43 2938.14 2938.43 2938.66 2939.04 2939.24 2939.40 2939.54 2939.67 2939.80 2940.09 2941.90 2943.19 2943.54 2944.18 2944.43 2943.91 2944.49 2944.78 2945.01 2945.22 A A A A A ... A No gage-height record RIO GRANGE DB MANATI BASIN **«» 50032590 LAGO DB MATRULLAS AT DAMSITB, PR LOCATION.—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> (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.B.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; minimum elevation, 2,392.81 ft (729.33 m), Sept. 10, 1989. EXTREMES OBSERVED FOR CURRENT YEAR.—Maximum elevation, 2,412.38 ft (735.29 m), Apr. 29,30 and May 3; minimum elevation, 2,403.93 ft (732.72 m), Sept. 28. DAY 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 ELEVATION (FEET NGVD), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY OBSERVATION AT 24:00 VALUES OCT NOV DEC JAN FBB MAR APR MAY JUN 1,845 2,945 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 2410.22 2410.22 2409.99 2409.62 2409.98 2411.19 2411.43 2411.50 2411.40 2411.23 2411.16 2411.31 2411.25 2411.18 2411.21 2411.13 2411.03 2411.11 2411.09 2411.06 2411.01 2410.97 2411.74 2411.72 2411.75 2411.60 2411.56 2411.41 2411.30 2411.43 2411.45 2411.10 2411.75 2409.62 2411.85 2411.67 2411.72 2411.54 2411.36 2411.24 2411.08 2411.15 2411.13 2411.01 2410.95 2410.91 2410.70 2410.40 2410.50 2410.90 2411.13 2411.07 2410.95 2411.44 2411.47 2411.63 2411.51 2411.39 2411.23 2411.29 2411.13 2411.84 2412.14 2411.69 --- 2411.27 2412.14 2410.40 2411.54 2411.44 2411.38 2411.30 2411.19 2411.37 2411.37 2411.22 2411.05 2410.85 2410.63 2410.46 2410.61 2410.67 2410.70 2410.61 2410.41 2410.17 2410.27 2410.53 2410.46 2410.32 2410.11 2409.86 2409.96 2410.24 2410.67 2410.75 2410.68 2410.57 2410.53 2410.71 2411.54 2409.86 2410.73 2410.95 2411.19 2411.17 2411.09 2411.13 2410.96 2410.63 2410.25 2410.25 2410.43 2410.33 2410.05 2409.70 2409.23 2408.85 2408.50 2408.54 2408.42 2408.13 2407.69 2407.57 2407.52 2407.55 2407.49 2407.51 2407.64 2407.95 2409.07 2409.30 2409.31 2409.33 2411.19 2407.49 2409.30 2409.27 2409.25 2409.08 2408.87 2408.93 2409.12 2409.10 2409.11 2409.15 2409.21 2409.26 2409.15 2409.19 2409.33 2409.44 2409.49 2409.51 2409.57 2409.87 2410.21 2410.33 2410.39 2410.44 2410.62 2410.79 2410.94 2411.10 ___ ___ — - 2409.64 2411.10 2408.87 2411.19 2411.20 2411.20 2411.21 2411.21 2411.27 2411.37 2411.38 2411.37 2411.36 2411.35 2411.34 2411.40 2411.47 2411.46 2411.45 2411.37 2411.24 2411.15 2411.26 2411.37 2411.48 2411.46 2411.38 2411.28 2411.18 2411.26 2411.35 2411.31 2411.33 2411.27 2411.32 2411.48 2411.15 2411.13 2410.99 2411.06 2411.16 2411.12 2411.09 2411.05 2411.02 2411.12 2411.22 2412.08 2411.64 2411.56 2411.60 2411.62 2411.59 2411.65 2411.66 2411.63 2411.52 2411.45 2411.50 2411.48 2411.62 2411.65 2411.51 2411.39 2411.94 2412.38 2411.94 —— 2411.48 2412.38 2410.99 2412.05 2412.37 2412.01 2411.81 2411.72 2411.67 2411.65 2411.73 2411.77 2411.73 2411.70 2411.73 2411.66 2411.77 2411.58 2411.44 2411.37 2411.23 2411.07 2410.90 2410.74 2410.64 2412.07 2411.78 2411.85 2411.73 2411.65 2411.81 2411.66 2411.77 2411.78 2411.63 2412.37 2410.64 2411.72 2411.65 2411.52 2411.50 2411.66 2411.72 2411.58 2411.46 2411.34 2411.17 2410.99 2410.72 2410.83 2410.81 2410.66 2410.51 2410.27 2410.08 2410.59 2411.21 2411.29 2411.41 2411.31 2411.18 2411.04 2410.87 2410.96 2410.90 2410.72 2410.53 --- 2411.07 2411.72 2410.08 2410.33 2410.14 2409.93 2409.98 2410.15 2410.15 2410.09 2409.99 2409.84 2409.59 2409.87 2410.02 2410.09 2410.27 2410.12 2409.88 2409.62 2409.63 2409.47 2409.22 2409.01 2408.86 2408.73 2408.51 2408.54 2408.71 2408.63 2408.41 2408.20 2407.95 2407.56 2409.40 2410.33 2407.56 2407.49 2407.56 2407.66 2407.81 2407.97 2407.91 2407.94 2408.07 2408.02 2407.82 2407.55 2407.34 2407.16 2407.16 2407.26 2407.72 2407.73 2407.64 2407.50 2407.28 2406.94 2406.70 2406.64 2406.48 2406.31 2406.13 2406.07 2406.30 2406.50 2406.49 2406.36 2407.21 2408.07 2406.07 2406.21 2406.04 2405.82 2406.14 2406.87 2406.99 2406.83 2406.62 2406.35 2406.21 2406.02 2405.69 2405.41 2405.12 2404.82 2404.53 2404.29 2404.32 2404.46 2404.40 2404.18 2404.15 2404.19 2404.03 2404.22 2404.27 2404.02 2404.02 2404.10 2404.02 --- 2405.14 2406.99 2404.02 WTR YR 1993 MEAN 2409.95 MAX 2412.38 MIN 2404.02 94 RIO QRANDB DE MANATI BASIN 50034000 RIO BAUTA NEAR 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 Orocovis. 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.--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 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 21 69 2 11 64 3 11 61 4 8.6 60 5 e93 47 6 e!43 38 7 e85 33 8 36 28 9 42 26 10 32 24 11 39 23 12 18 22 13 13 22 14 e49 21 15 e81 20 16 e28 27 17 23 37 18 25 24 19 22 23 20 20 50 21 16 62 22 e!5 59 23 e!94 79 24 e!94 49 25 el!2 34 26 e55 28 27 110 27 28 101 e!95 29 58 e!94 30 68 144 31 48 --- TOTAL 1771.6 1590 MEAN 57.1 53.0 MAX 194 195 MIN 8.6 20 AC-FT 3510 3150 CFSM 3.42 3.17 IN. 3.95 3.54 STATISTICS OF MONTHLY MEAN MEAN 96.8 58.9 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 90 PERCENT EXCEEDS 76 52 41 35 33 30 28 26 25 25 24 23 24 e59 e67 38 33 30 28 27 25 36 36 34 31 101 104 61 45 37 34 1268 40.9 104 23 2520 2.45 2.82 DATA 30.4 108 1971 8.95 1992 FOR 31 29 29 28 27 28 33 33 27 25 24 24 23 24 22 22 22 22 22 21 21 22 24 22 22 20 20 21 64 37 34 823 26.5 64 20 1630 1.59 1.83 38 21 21 18 16 15 14 13 13 13 12 12 12 12 12 12 14 12 11 33 29 15 12 11 11 10 10 9.5 ___ ___ — - 431.5 15.4 38 9.5 856 .92 .96 FOR WATER YEARS 1969 21.2 83.4 1992 6.62 1973 14.2 30.9 1971 6.26 1977 e9.6 e!3 e!2 ell elO 10 9.7 9.4 9.5 9.2 9.0 9.0 9.1 9.1 9.2 9.6 9.8 9.4 9.1 9.6 9.5 8.8 9.3 11 12 9.7 9.4 9.0 9.3 10 11 305.3 9.85 13 8.8 606 .59 .68 - 1993 15.9 59.9 1972 5.57 1977 1992 CALENDAR YEAR 15451.2 42.2 922 7.2 7.9 30650 2.53 34.42 82 20 8.6 Jan 6 Jan 2 Aug 29 9.1 9.1 9.2 9.5 9.4 9.1 9.3 9.3 11 11 100 29 181 76 e68 e62 e29 e28 19 15 15 13 12 20 25 15 13 254 485 170 --- 1725.0 57.5 485 9.1 3420 3.44 3.84 e!38 e354 e!65 e68 e43 33 28 26 30 e33 29 24 21 41 33 24 19 17 16 16 16 19 e274 e!24 e!96 el!5 e66 e91 e59 43 39 2200 71.0 354 16 4360 4.25 4.90 33 30 e27 25 23 22 21 21 21 20 18 17 17 16 18 20 16 15 48 e75 e30 23 19 18 17 16 e!7 e!9 e!8 el 9 --- 699 23.3 75 15 1390 1.40 1.56 e!8 e!6 e!7 e22 e!7 e!6 e!5 e!6 e!3 12 e29 e26 17 26 16 14 13 12 12 12 11 e!3 e!6 13 13 13 e!5 12 11 11 11 478 15.4 29 11 948 .92 1.06 10 10 10 9.8 9.7 9.8 9.7 9.6 9.6 9.6 9.6 9.8 9.2 9.0 9.2 45 e21 13 12 11 10 10 13 ell ell elO ell e22 e21 e!4 e!3 392.6 12.7 45 9.0 779 .76 .87 e9.8 elO e!2 e200 e210 e220 e90 25 17 14 14 12 10 10 10 10 20 16 14 12 12 10 20 26 19 16 13 25 23 14 1113.8 37.1 220 9.8 2210 2.22 2.48 , BY WATER YEAR (WY) 28.9 80.2 1980 6.23 1977 FOR 1993 12797 35 485 8 9 2430 12 8 25380 2 28 68 21 9 51.0 179 1981 7.05 1973 WATER YEAR .8 .1 Apr 29 .6 Oct 4 .2 Mar 9 Apr 29 .58 Apr 29 .4 Oct 5 .10 .51 .7 20.5 78.6 1979 4.10 1977 17.0 104 1979 5.22 1974 WATER 35 79 13 3870 3 3 17800 21 2 25920 2 29 66 13 6 22.2 152 1979 6.76 1976 YEARS 1969 .8 .3 .2 Oct .0 Jul .4 Jul Oct .90 Oct .8 Jul .14 .10 .0 53.4 149 1979 9.82 1992 - 1993 1979 1977 9 1970 23 1977 20 1977 9 1970 9 1970 23 1977 e Estimated RIO GRANDB DB MANATI BASIN vv 50035000 RIO GRANDB DE MANATI AT CIALES, 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 AREA.--128 mi* (332 km»), excludes 6.0 mi» (15.5 km*), the runoff from which is diverted through El Guineo and de Matrullas reservoirs. WATER-DISCHARGE RECORDS PERIOD OF 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 Grand* de Manati at Highway 145 at Ciales at site 1.6 mi (2.6 km) downstream, drainage area 132 mi* (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. Gage-height and precipitation satellite telemetry at station. EXTREMES OUTSIDE PERIOD OF 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. DISCHARGE. CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV MAR APR JUL AUG SEP 1 241 367 2 224 345 3 140 253 4 330 501 5 e241 372 6 e515 233 7 434 183 8 226 158 9 215 142 10 150 136 11 209 128 12 136 122 13 106 253 14 100 166 15 96 167 16 86 216 17 358 263 18 480 161 19 385 150 20 199 250 21 133 265 22 134 233 23 491 362 24 636 212 25 650 167 26 315 136 27 270 284 28 332 1140 29 218 715 30 398 664 31 391 TOTAL 8839 8744 MEAN 285 291 MAX 650 1140 MIN 86 122 AC-FT 17530 17340 CFSM 2.23 2.28 IN. 2.57 2.54 STATISTICS OF MONTHLY MEAN MEAN 476 379 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 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 326 235 180 158 141 127 119 107 104 105 99 98 142 374 747 253 194 183 158 141 133 194 231 193 204 1340 860 449 330 269 216 8410 271 1340 98 16680 2.12 2.44 DATA 276 1296 1966 64.5 1992 FOR 183 166 166 181 157 157 278 338 196 165 148 145 141 133 128 121 121 117 115 113 111 110 144 122 115 107 100 103 453 285 309 5228 169 453 100 10370 1.32 1.52 595 221 186 169 151 136 125 116 112 109 103 101 101 97 94 120 142 103 95 174 277 156 114 100 94 91 87 84 ___ ___ --- 4053 145 595 84 8040 1.13 1.18 FOR WATER YEARS 1961 174 479 1992 64.1 1984 138 424 1969 47.9 1984 82 83 83 79 78 78 75 72 72 79 72 69 69 68 64 71 95 77 68 68 97 62 60 69 69 66 61 64 64 68 83 2265 73.1 97 60 4490 .57 .66 - 1993 148 477 1969 36.5 1984 1992 CALENDAR YEAR 97624 267 5240 45 57 193600 2.08 28.37 449 130 69 Jan 6 Jan 4 Mar 1 61 59 SB 57 57 56 54 159 304 293 1300 804 1040 1510 1110 896 532 421 255 294 385 316 185 146 179 140 124 434 3710 1780 —— 16719 557 3710 54 33160 4.35 4.86 1790 3030 1520 602 401 363 323 476 1500 597 450 367 305 353 326 262 246 208 193 182 183 217 1020 695 911 722 451 535 440 326 351 19345 624 3030 182 38370 4.88 5.62 260 230 202 185 172 169 169 165 172 170 154 141 143 145 141 152 132 125 217 423 207 161 152 138 126 121 114 113 118 135 --- 5052 168 423 113 10020 1.32 1.47 115 109 109 109 105 101 99 103 97 92 200 307 132 157 123 106 101 95 93 94 92 100 217 • 181 • 174 121 124 104 93 91 91 3835 124 307 91 7610 .97 1.11 91 88 86 84 84 84 84 84 84 84 84 84 84 81 81 336 250 113 97 87 84 83 105 89 82 81 81 93 175 225 144 3392 109 336 81 6730 .85 .99 97 85 80 461 382 659 471 254 132 104 114 92 85 85 87 119 394 515 584 313 163 127 362 461 153 118 101 222 234 123 —— 7177 239 659 80 14240 1.87 2.09 , BY WATER YEAR (WY) 291 1174 1969 28.5 1984 FOR 1993 93059 255 3710 54 57 17800 10. 54 184600 1, 27, 478 148 81 477 2293 1985 71.4 1989 WATER YEAR Apr 29 Apr 7 Apr 1 Apr 29 .15 Apr 29 Apr 6 .99 .05 162 458 1979 40.2 1977 110 438 1979 40.2 1974 WATER 256 520 118 42700 5 22 125000 24 20 185800 2 27 460 118 55 153 1212 1979 33.6 1984 YEARS 1961 - May 18 .0 Jul 9 Apr 16 Oct 9 .00 Oct 9 Apr 20 .00 .22 285 994 1979 77.7 1977 1993 1971 1974 1985 1971 1984 1970 1970 1984 • Estimated 96 RI° GRANDB DB MANATI BASIN 5003SSOO RIO QRANDB 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 dales plaza. DRAINAGE ARBA.--136 mi 1 (3S2 km*) this excludes the 6 mi* (1S.S km*) upstream from Lago El Guineo and Lago de Matrullas, flow from which is diverted to Rio Jacaguas. PERIOD OP RECORD.—Water years 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 21... DEC 22... MAR 1993 04. .. APR 29. .. JUN 23. .. AUG 20... TIME 1155 1130 1040 1400 1215 1300 DIS- CHARGE, INST. CUBIC FEET PER SECOND 102 100 133 1980 136 209 SPE- CIFIC CON- DUCT- ANCE (US/CM) 223 262 224 194 223 269 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.6 8.0 8.3 7.2 8.2 8.1 TEMPER- ATURE WATER (DBG C) 26. 5 23.1 24.0 26. 5 28. 5 27.0 TUR- BID- ITY (NTU) S.I 29 2.9 162 S.6 14 OXYGEN, DIS- SOLVED (MG/L) 8.4 8.1 7.4 10.0 8.3 7.2 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 100 92 88 124 106 90 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 14 11 <10 13 14 <10 COLI- FORM, FECAL, 0.4S UM-MF (COLS./ 100 ML) K1700 3900 SO S7000 4400 3100 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 260 2900 190 6SOO K930 870 DATE OCT 1992 21... DEC 22... MAR 1993 04. .. APR 29... JUN 23... AUG 20... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (HG/L TOT PLD SOLVED AS HG/L AS (HG/L MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L CAC03) CAC03 AS CA) AS HG) AS NA) SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY CHLO- SIUM, WAT WH SULPATB RIDE, DIS- TOT PET SULPIDB DIS- DIS- SOLVED FIELD TOTAL SOLVED SOLVED (HG/L MG/L AS (MG/L (HG/L (HG/L AS K) CAC03 AS S) AS S04) AS CL) 85 1 21 7.9 10 O.S 2.4 82 <O.S 10 11 93 no 130 5 24 16 74 3 4.5 64 <0.5 120 92 37 22 8.9 12 O.S 2.5 100 — 9.5 13 SOLIDS, RESIDUE DATE OCT 1992 21... DEC 22... MAR 1993 04.. . APR 29... JUN 23.. . AUG 20.. . FLUO- RIDB, DIS- SOLVED (MG/L AS P) 0.10 -- -- 0.10 -- 0.10 SILICA, DIS- SOLVED (HG/L AS SI02) 24 -- -- 27 -- 27 SUM OP CONSTI- TUENTS, DIS- SOLVED (MG/L) 136 -- -- 227 -- 155 SOLIDS, DIS- SOLVED (TONS PER DAY) 37.3 -- -- 1214 -- 87.4 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 23 9 2 <1 18 16 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.720 0.430 0.290 0.390 0.590 0.290 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.020 0.070 0.010 0.010 0.010 0.010 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 0.740 0.500 0.300 0.400 0.600 0.300 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.040 0.030 0.020 0.030 0.020 0.030 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.16 0.37 0.68 0.27 0.18 0.37 non-ideal count RIO GRANDS DB MANATI BASIN 50035500 RIO GRANDS DB MANATI AT HIGHWAY 149 AT CIALBS, PR--Continued HATBR-QOALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 97 DATE OCT 1992 21... DEC 22... MAR 1993 04... APR 29... JUN 23... AUQ 20... DATE OCT 1992 21... DEC 22... MAR 1993 04... APR 29... JUN 23... AOG 20... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.20 0.40 0.70 0.30 0.20 0.40 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) 1000 -- -- 5100 -- -- NITRO- GEN, TOTAL (MG/L AS N) 0.94 1.3 1.0 0.70 0.80 0.70 LEAD, TOTAL RECOV- ERABLE (UQ/L AS PB) 5 -- — 5 — -- NITRO- GEN, TOTAL (MG/L AS NO3) 4.2 5.2 4.4 3.1 3.5 5.2 MANGA- NESE, TOTAL RECOV- ERABLE (UQ/L AS MN) 40 -- -- 220 -- -- PHOS- PHORUS ARSENIC TOTAL TOTAL (MG/L (UG/L AS P) AS AS) 0.080 <1 0.090 0.050 0.100 <1 0.080 0.070 MERCURY TOTAL SBLE- RECOV- NIUM, BRABLB TOTAL (UG/L (UG/L AS HG) AS SB) 0.2 <1 __ __ 0.1 <1 — __ BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) •(100 -- — •(100 — " SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) <1 -- -- <1 -- -- BORON, TOTAL RECOV- ERABLE (UG/L AS B) 20 -- -- 40 -- "" ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) <10 -- -- 20 -- -- CHRO- CADMIUM MIUM, TOTAL TOTAL RECOV- RECOV- ERABLE BRABLB (UG/L (UG/L AS CD) AS CR) •(1 <1 — __ •<! •<! — .. CYANIDE TOTAL PHENOLS (MG/L TOTAL AS CN) (UG/L) <0.010 <1 __ __ •(0.010 <1 __ __ COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) <10 — — <20 -- " MBTHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 0.03 -- -- 0.01 -- -- 0O RIO GRANDB DB MANATI BASIN 50035950 RIO CIALITOS AT HIGHWAY 649 AT CIALBS, PR WATER-QUALITY 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 1 (44.0 km1 ). PERIOD OF RECORD.--Water years 1969-71, 1974 to current year. WATER-QUALITY DATA 0.7 mi (1.1 km) DATE OCT 1992 21. .. DEC 21... MAR 1993 04. .. MAY 03. .. JUN 23... AUG 20... TIME 1340 1300 1145 1515 1350 1405 DIS- CHARGE, INST. CUBIC FEET PER SECOND 5.7 12.2 5.0 72 3.6 4.0 SPE- CIFIC CON- DUCT- ANCE (US/CM) 235 312 420 318 213 194 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.1 7.9 8.3 7.6 7.7 7.2 TEMPER- ATURE WATER (DBG C) 25.5 23.2 26.5 22.0 26.5 23.5 TUR- BID- ITY (NTU) 13 2.4 11 15 12 82 OXYGEN, DIS- SOLVED (MG/L) 8.3 7.8 8.5 8.0 8.2 6.0 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 100 95 86 91 81 70 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 70 <10 <10 16 <10 22 COLI- PORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 3600 4500 540 460 K900 K60000 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 2200 3500 K870 330 250 6800 DATE OCT 1992 21... DEC 21. .. MAR 1993 04... MAY 03. .. JUN 23... AUG 20. .. HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MG/L TOT FLD SOLVED AS MG/L AS (MG/L CACO3) CACO3 97 1 28 64 0 19 95 2 27 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS NA) 6.6 10 SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY SIUM, WAT WH DIS- TOT FET SULFIDE SOLVED FIELD TOTAL (MG/L MG/L AS (MG/L AS K) 0.4 3.3 4.1 8.6 0.5 1.8 6.8 12 0.5 2.0 CAC03 96 70 100 120 98 81 CHLO- SULFATB RIDE, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS S) AS S04) AS CL) <0.5 6.9 10 <0.5 7.1 9.5 6.5 11 SOLIDS, RESIDUE DATE OCT 1992 21.. . DEC 21... MAR 1993 04.. . MAY 03.. . JUN 23... AUG 20... FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.10 -- -- 0.10 -- <0.10 SILICA, DIS- SOLVED (MG/L AS SI02) 29 — — 24 __ 30 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 151 -- -- 146 __ 155 SOLIDS, DIS- SOLVED (TONS PER DAY) 2.33 -_ -- 28.5 __ 1.67 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) __ 15 <1 24 9 8 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.680 1.49 1.59 1.18 0.990 0.820 NITRO- GEN, NITRITE TOTAL (MG/L AS N) <0.010 0.010 0.010 0.020 0.010 0.020 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 0.680 1.50 1.60 1.20 1.00 0.840 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.020 0.010 0.020 0.040 0.010 0.030 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.28 0.19 -- 0.16 __ 0.67 non-ideal count RIO GRANDE DE MANATI BASIN 50035950 RIO CIALITOS AT HIGHWAY 649 AT CIALBS, PR--Continued WATER-QOALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 21... DEC 21... MAR 1993 04... MAY 03... JUN 23... AUG 20... DATE OCT 1992 21... DEC 21.. . MAR 1993 04.. . MAY 03. .. JUN 23... AUG 20... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MQ/L AS N) 0.30 0.20 <0.20 0.20 <0.20 0.70 IRON, TOTAL RECOV- ERABLE (UG/L AS FE) 140 -- -- 710 -- -- NITRO- GEN, TOTAL (MG/L AS N) 0.98 1.7 -- 1.4 -- 1.5 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) 1 -- — <1 -- -- NITRO- GEN, TOTAL (MG/L AS NO3) 4.3 7.5 -- 6.2 -- 6.8 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) 20 -- -- 30 -- -- PHOS- PHORUS ARSENIC TOTAL TOTAL (MG/L (UG/L AS P) AS AS) 0.110 <1 0.320 0.280 0.160 1 0.180 0.410 MERCURY TOTAL SELE- RECOV- NIUM, ERABLB TOTAL (UG/L (UG/L AS HG) AS SB) <0.10 <1 __ __ <0.10 <1 __ __ BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 — — <100 -- — — SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) <1 -- -- <1 -- -- BORON, TOTAL RECOV- ERABLE (UG/L AS B) 60 -- -- 20 -- — — ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) <10 -- -- <10 -- -- CHRO- CADMIUM MIUM, TOTAL TOTAL RBCOV- RECOV- ERABLE ERABLE (UG/L (UG/L AS CD) AS CR) <1 1 — — <1 8 __ — — — - CYANIDE TOTAL PHENOLS (MG/L TOTAL AS CN) (UG/L) <0.010 1 __ __ <0.010 <1 __ __ COPPER, TOTAL RECOV- ERABLE (UG/L AS CO) <10 -- -- 10 -- " MBTHY- LBNB BLUE ACTIVE SUB- STANCE (MG/L) 0.05 -- -- 0.03 -- -- 100 LOCATION.--Lat 18°25'52' west of Manati. RIO GRANDE DE MANATI BASIN 50038100 RIO GRANDE DE MANATI AT HIGHWAY 2 NEAR MANATI, PR long 66°31'37", Hydrologic Unit 21010002, at bridge on Highway 2, and 2.3 mi (3.7 km) DRAINAGE AREA.--197 mi 1 (510 km'), approximately, of which about 38 mi> (98 km9 ) is partly or entirely noncontributi.no, excludes 6.0 mi* (15.5 km9 ) upstream from Lago El Guineo and Lago de Matrullas. WATER-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.—Water-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) . DAY OCT DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 268 457 2 220 453 3 308 285 4 160 662 5 585 504 6 1310 306 7 909 236 8 326 200 9 283 176 10 233 165 11 257 148 12 211 136 13 176 190 14 161 266 15 239 178 16 200 216 17 351 362 18 609 207 19 800 215 20 315 243 21 236 430 22 208 263 23 385 494 24 954 308 25 987 241 26 493 196 27 508 263 28 507 1530 29 358 1090 30 427 1230 31 512 TOTAL 13496 11650 MEAN 435 388 MAX 1310 1530 MIN 160 136 AC-FT 26770 23110 CFSM 2.21 1.97 IN. 2.55 2.20 STATISTICS OF MONTHLY MEAN MEAN 801 580 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-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 513 364 291 255 231 215 205 194 185 180 174 168 197 907 1860 565 360 311 268 243 225 250 346 296 344 1260 2050 811 593 471 381 14713 475 2050 168 29180 2.41 2.78 DATA 392 1498 1971 101 1992 FOR 329 293 275 295 264 265 321 572 316 268 246 236 229 221 214 206 200 195 189 185 183 187 223 207 189 183 176 183 411 375 319 7955 257 572 176 15780 1.30 1.50 FOR WATER 260 771 1992 105 1984 841 325 259 242 217 200 193 186 180 174 171 167 169 165 159 155 211 174 161 170 400 244 195 173 161 155 153 147 -_- .__ --- 6147 220 841 147 12190 1.11 1.16 YEARS 1970 206 444 1988 87.6 1984 142 152 151 140 134 132 132 129 131 138 130 121 120 117 114 127 160 135 122 113 140 120 111 124 115 109 100 109 101 119 140 3928 127 160 100 7790 .64 .74 - 1993 195 521 1972 68.4 1984 1992 CALENDAR YEAR 140264 383 8410 69 80 278200 1. 26. 675 180 92 Jan 6 Sep 16 Sep 13 95 49 107 91 88 85 84 84 81 96 378 351 e954 e!640 1190 2130 1860 1640 840 715 451 408 667 516 313 252 259 234 233 386 5210 9770 --- 31113 1037 9770 81 61710 5.26 5.88 , BY WATER 392 1037 1993 60.1 1984 1960 4830 4270 1290 783 779 859 682 2840 1210 827 674 565 544 583 522 475 424 419 392 402 428 1080 1800 1360 1460 795 656 845 455 501 34710 1120 4830 392 68850 5.68 6.55 YEAR (WY) 704 3178 1985 93.7 1989 386 348 319 295 278 269 263 253 263 254 243 227 222 220 212 216 208 193 220 447 275 222 210 195 182 178 175 174 181 189 7317 244 447 174 14510 1.24 1.38 251 747 1987 78.7 1977 FOR 1993 WATER YEAR 152142 417 9770 81 87 30200 30.84 79 301800 2.12 28.73 827 219 128 Apr 30 Apr 7 Apr 2 Apr 29 Apr 29 Apr 8 184 173 178 182 176 170 168 176 171 164 183 389 219 208 198 175 167 162 156 154 152 156 247 190 228 175 179 162 149 144 141 5676 183 389 141 11260 .93 1.07 165 577 1979 75.2 1984 WATER 383 756 172 55900 34 38 97200 33 33 277100 1 26 674 175 92 138 136 133 128 128 130 129 124 122 124 121 124 119 116 115 208 460 186 155 144 135 131 145 153 130 125 123 128 161 361 217 4849 156 460 115 9620 .79 .92 226 1644 1979 67.9 1984 YEARS 1970 May May May Oct .79 Oct May .94 .38 159 138 128 177 778 522 1040 409 225 177 180 161 142 132 131 200 448 727 828 674 246 188 190 981 325 224 189 213 403 253 --- 10588 353 1040 128 21000 1.79 2.00 435 1510 1979 127 1983 - 1993 1971 1974 18 1985 12 1984 7 1984 7 1985 7 1985 12 1984 RIO GRANDS DS MANATI BASIN 50038100 RIO GRANDS DB MANATI AT HIGHWAY 2 NEAR MANATI, PR--Continued (National stream-quality accounting network station) WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1969 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 101 DATE OCT 1992 23... DEC 21... FBB 1993 22... APR 30... JUN 25. .. SEP 23... DATE OCT 1992 23... DEC 21. .. FBB 1993 22. .. APR 30. .. JUN 25... SEP 23... DATE OCT 1992 23... DEC 21... FBB 1993 22. .. APR 30... JUN 25. .. SEP 23. .. TIME 1125 0915 1025 1025 0950 1210 HARD- NESS NONCARB WH WAT TOT FLD MG/L AS CACO3 91 130 120 100 130 88 SOLIDS, RESIDUE AT 180 DBG. C DIS- SOLVED (MG/L) 157 184 157 140 174 158 DIS- CHARGE, INST. CUBIC FEET PER SECOND 505 228 251 560 183 168 CALCIUM DIS- SOLVED (MG/L AS CA) 31 36 29 22 36 33 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 156 170 152 112 173 162 SPE- CIFIC CON- DUCT- ANCE (US/CM) 256 286 242 200 285 256 MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) 7.0 7.1 6.9 3.7 7.3 7.3 SOLIDS, DIS- SOLVED (TONS PER DAY) 213 105 103 169 85 73 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.2 6.5 7.4 6.8 7.2 7.2 SODIUM, DIS- SOLVED (MG/L AS HA) 10 11 10 7.2 11 10 NITRO- GEN, N02+NO3 DIS- SOLVED (MG/L AS N) 0.880 0.800 0.950 0.960 0.720 1.00 TEMPER- ATURE WATER (DBG C) 28.5 23.0 22.5 22.7 29.0 28.1 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) 0.360 0.080 0.060 0.530 0.050 0.080 TUR- BID- ITY (NTU) 160 6.0 20 240 1.7 43 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 2.3 2.4 2.1 3.2 1.9 2.2 NITRO- GEN, AMMONIA DIS- SOLVED (MG/L AS NH4) 0.46 0.10 0.08 0.68 0.06 0.10 OXYGEN, DIS- SOLVED (MG/L) 5.4 5.0 4.4 8.0 5.7 6.7 ALKA- LINITY WAT WH TOT FBT FIELD MG/L AS CAC03 140 120 96 79 120 110 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.50 0.40 0.40 2.2 0.40 -- OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 68 57 55 91 73 86 SULFATB DIS- SOLVED (MG/L AS SO4) 9.1 8.8 8.1 8.6 8.0 9.7 PHOS- PHORUS TOTAL (MG/L AS P) 0.240 0.260 0.130 0.300 0.120 -- COLI- FORM, FECAL, 0.7 UM-MF (COLS./ 100 ML) K680 4200 K18000 K60000 27000 K7600 CHLO- RIDE, DIS- SOLVED (MG/L AS CL) 11 13 12 10 12 11 PHOS- PHORUS DIS- SOLVED (MG/L AS P) 0.060 0.80 0.070 0.230 0.080 0.050 STREP- TOCOCCI FECAL, KF AGAR (COLS. PER 100 ML) K2000 4900 2200 K120000 370 400 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) 0.060 0.040 0.090 0.210 0.060 0.060 HARD- NESS TOTAL (MG/L AS CACO3) 110 120 100 70 120 110 SILICA, DIS- SOLVED (MG/L AS SIO2) 21 22 21 15 21 21 PHOS- PHATE, ORTHO, DIS- SOLVED (MG/L AS PO4) 0.18 0.09 0.28 0.64 0.18 0.18 K = non- ideal count 102 RIO GRANDS DE MANATI BASIN 50038100 RIO GRANDE DB MANATI AT HIGHWAY 2 NEAR MANATI, PR—Continued (National atream-quality accounting network station) DATE OCT 1992 23... DEC 21. .. FBB 1993 22... APR 30... JUN 25... SEP 23... ALUM- INUM, DIS- SOLVED (UG/L AS AL) ARSENIC DIS- SOLVED (UG/L AS AS) BARIUM, DIS- SOLVED (UG/L AS BA) BERYL- LIUM, DIS- SOLVED (UG/L AS BE) CADMIUM DIS- SOLVED (UG/L AS CD) CHRO- MIUM, DIS- SOLVED (UG/L AS CR) COBALT, DIS- SOLVED (UG/L AS CO) COPPER, DIS- SOLVED (UG/L AS CO) IRON, DIS- SOLVED (UG/L AS FB) LEAD, DIS- SOLVED (UG/L AS PB) LITHIUM DIS- SOLVED (UG/L AS LI) 80 20 50 39 <0.5 36 <0.5 40 <0.5 43 <0.5 <3 <3 <3 <3 13 66 22 73 <4 <4 <4 <4 MANGA- MOLYB- SBLB- DATE OCT 1992 23. . . DEC 21. . . FBB 1993 22. .. APR 30. .. JUN 25. .. SEP 23... NESB, MERCURY DENUM, NICKEL, NIUM, SILVER, DIS- SOLVED (UG/L AS MN) 17 22 22 DIS- SOLVED (UG/L AS HG) 0.1 DIS- SOLVED (UG/L AS MO) DIS- SOLVED (UG/L AS NI) DIS- SOLVED (UG/L AS SB) DIS- SOLVED (UG/L AS AG) STRON- VANA- TIUM, DIUM, DIS- SOLVED (UG/L AS SR) 150 150 160 160 DIS- SOLVED (UG/L AS V) <6 ZINC, DIS- SOLVED (UG/L AS ZN) <3 8 17 6 4 <6 <3 RIO GRANDB DB MANATI BASIN 50038100 RIO GRANDB DB MANATI AT HIGHWAY 2 NEAR MANATI, PR—Continued (National stream-quality accounting network station) WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 103 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT DATE DEC 1992 21.. . FEE 1993 22... APR 30... JUN 25... SEP 23.. . TIME 0915 1025 1025 0950 1210 STREAM- FLOW, INSTAN- TANEOUS (CFS) 228 251 560 183 168 SEDI- MENT, SUS- PENDED (MG/L) 40 57 705 10 74 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 24 39 1065 5 34 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 81 92 76 25 94 PESTICIDE ANALYSES DATE JUN 1993 23... TIME 1005 PCB, TOTAL (UG/L) ALDRIN, TOTAL (UG/L) <0.010 CHLOR- DANB, TOTAL (UG/L) ODD, 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 DATE JUN 1993 23.. . ENDRIN WATER UNFLTRD RBC (UG/L) <0.010 BTHION, TOTAL (UG/L) <0.01 HEPTA- CHLOR, TOTAL (UG/L) <0.010 HBPTA- CHLOR BPOXIDB TOTAL (UG/L) <0.010 LINDANB TOTAL (UG/L) <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 MIRBX, TOTAL (UG/L) <0.01 DATE JUN 1993 23... PARA- THION, TOTAL (UG/L) <0.01 NAPH- THA- LENES, POLY- CHLOR. TOTAL (UG/L) <0.10 PBR- THANE TOTAL (UG/L) <0.1 TOX- APHENB, TOTAL (UG/L) <1 TOTAL TRI- THION (UG/L) <0.01 2,4-D, TOTAL (UG/L) <0.01 2,4,5-T TOTAL (UG/L) <0.01 2, 4 -DP TOTAL (UG/L) <0.01 SILVEX, TOTAL (UG/L) <0.01 104 LAGUNA TORTUGUBRO BASIN 50038200 LACUNA TORTUGUBRO OUTLET NEAR VEGA BAJA, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°28'29", long 66°26'50", at bridge on Highway 686, 4.2 mi (6.8 km) northeast of Manati. DRAINAGE AREA.--Indeterminate. PERIOD OP RECORD.--Water years 1964-66, 1969-71, 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 OCT 02 DEC 09 FEE 08 APR 19 MAY 27 SEP 07 OCT 02 DEC 09 PBB 08 APR 19 MAY 27 SEP 07 OCT 02 DEC 09 PBB 08 APR 19 MAY 27 SEP 07 K = DATE TIME 1992 0830 0830 1993 0830 0840 1150 12 15 ALKA- LINITY WAT WH TOT PET FIELD DATE MG/L AS CAC03 1992 120 140 1993 130 130 120 120 NITRO- GEN, TOTAL DATE (MG/L AS N03) 1992 6.5 5.8 1993 12 9.3 11 8.4 non- ideal count DIS- CHARGE, IN ST. CUBIC PBBT PER SECOND 12 12 19 4.04 7.39 8.35 SULPIDB TOTAL (MG/L AS S) <0.5 -- — <0.5 -- -- PHOS- PHORUS TOTAL (MG/L AS P) <0.010 0.010 0.010 0.030 <0.010 0.010 SPE- CIFIC CON- DUCT- ANCE (US/CM) 1470 1240 1090 1330 1150 1180 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) <1 4 7 5 5 6 BORON, TOTAL RECOV- ERABLE (UG/L AS B) 90 -- -- 100 -- -- PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.1 6.4 7.8 7.7 7.6 7.5 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.550 0.390 0.780 0.980 1.08 0.580 COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) <10 -- -- 10 -- -- TEMPER- ATURE WATER (DBG C) 29.0 26.5 26.0 27.5 29.0 30.4 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.010 0.010 0.020 0.020 0.020 0.020 IRON, TOTAL RECOV- ERABLE (UG/L AS PB) 50 -- -- 120 -- -- OXYGEN, DIS- SOLVED (MG/L) 6.2 6.0 5.2 5.8 6.4 5.6 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 0.560 0.400 0.800 1.00 1.10 0.600 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MM) 10 -- __ 20 -- -- OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 79 73 63 72 82 70 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.400 0.230 0.440 0.090 0.330 0.200 ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) <10 -- -- <10 -- -- OXYGEN DEMAND, CHEM- ICAL (HIGH *~ LEVEL) (MG/L) 34 30 33 37 48 35 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.50 0.67 1.4 1.0 1.1 1.1 CYANIDE TOTAL (MG/L AS CN) <0.010 -- -- <0.010 — — COLI- PORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K80 50 K100 K175 660 100 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.90 0.90 1.8 1.1 1.4 1.3 PHENOLS TOTAL (UG/L) 3 -- -- 4 -- -- STREP- TOCOCCI FECAL, (COLS. PER 100 ML) K70 60 K300 540 53 70 NITRO- GEN, TOTAL (MG/L AS N) 1.5 1.3 2.6 2.1 2.5 1.9 MBTHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 0.06 — -- 0.10 — -- 105 EXPLANATION 038320 SURFACE-WATER STATION AND NUMBER 0397 QUALITY-OF-WATER STATION AND NUMBER 213 WELL AND WELL NUMBER r~ M °P °**a —S,_„ t&® jy*n ,J« Figure 17.--Rfo Cibuco basin. 106 RIO CIBCCO BASIN 50038320 RIO CIBCCO BELOW COROZAL, PR LOCATION.--Lat 18°21'13", long 66<>20'07", Hydrologic Unit 21010001, on right bank, 150 ft (46 m) downstream from junction with Rio Corozal, and 1.4 mi (2.3 km) northwest of Corozal. DRAINAGE AREA.--15.1 mi» (39.1km1 ). HATER-DISCHARGE RECORDS PERIOD OF RECORD.--May 1969 to current year. GAGE.--Hater-stage recorder. Elevation of gage is 195 ft (59 m), from topographic map. REMARKS.--Records fair. Gage-height and precipitation satellite telemetry at station. Daily discharge affected by sewage treatment plant about 0.6 mi (1.0 km) upstream. DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL ACG 1 12 6.5 2 43 6.2 3 18 15 4 11 82 5 12 21 6 9.1 14 7 8.5 12 8 8.5 11 9 9.4 13 10 8.9 11 11 11 8.9 12 9.3 8.3 13 8.1 107 14 8.5 20 15 8.2 12 16 8.1 9.5 17 19 9.0 18 48 9.4 19 16 7.4 20 9.0 17 21 7.3 9.1 22 14 19 23 20 13 24 13 12 25 12 11 26 8.6 12 27 8.2 332 28 7.4 75 29 6.9 65 30 8.1 37 31 6.5 - — TOTAL 397.6 985.3 MEAN 12 . 8 32 . 8 MAX 48 332 MIN 6.5 6.2 AC-FT 789 1950 CFSM .85 2.18 IN. .98 2.43 STATISTICS OF MONTHLY MEAN MEAN 42.3 46.1 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 ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 26 21 19 19 18 18 17 18 17 18 17 17 17 28 34 17 21 18 18 18 17 35 22 40 48 356 87 99 65 35 23 1223 39.5 356 17 2430 2.61 3.01 18 14 12 11 20 15 46 25 15 12 12 12 11 10 9.6 8.7 8.3 7.9 7.7 7.6 7.9 14 14 10 16 11 10 10 20 15 25 435.7 14.1 46 7.6 864 .93 1.07 DATA FOR HATER 37.2 169 1971 6.86 1979 FOR 25.2 69.6 1992 8.36 1978 25 15 17 17 15 13 13 13 12 11 11 10 10 9.4 9.5 13 12 9.8 9.2 34 17 12 11 9.2 8.0 10 8.6 10___ ___ --- 364.7 13.0 34 8.0 723 .86 .90 YEARS 1969 21.6 51.3 1988 8.11 1984 10 10 9.3 9.3 8.9 9.4 9.6 9.2 9.3 8.9 8.9 8.4 7.5 6.7 7.3 10 11 6.8 6.1 7.0 5.8 5.5 12 7.0 8.2 8.3 7.6 7.3 7.8 9.7 10 262.8 8.48 12 5.5 521 .56 .65 - 1993 23.1 65.1 1981 4.36 1984 1992 CALENDAR YEAR 8947. 24. 1260 6. 7. 17750 1. 22. 37 12 8. 8 4 Jan 5 2 Nov 2 1 Oct 27 62 04 2 6.4 6.5 6.4 5.9 5.5 5.7 5.9 39 73 26 705 89 55 228 166 98 46 32 25 46 129 67 38 32 31 28 60 143 657 176--- 3031.3 101 705 5.5 6010 6.69 7.47 204 207 91 62 46 117 210 118 225 110 95 66 53 71 46 43 39 39 38 37 36 36 81 39 56 41 81 37 33 31 29 2417 78.0 225 29 4790 5.16 5.95 27 25 24 23 23 22 23 26 25 26 23 21 21 21 22 21 21 18 46 36 23 23 20 20 19 18 21 30 24 29 721 24.0 46 18 1430 1.59 1.78 22 23 24 21 19 19 30 22 19 19 102 36 25 22 20 21 20 19 19 18 18 26 25 68 25 66 35 23 18 18 17 859 27.7 102 17 1700 1.84 2.12 17 16 16 16 16 16 15 14 16 15 14 15 15 14 16 41 18 16 14 13 13 13 12 12 11 11 11 14 13 11 11 465 15.0 41 11 922 .99 1.15 11 11 10 14 17 20 23 14 16 12 13 11 11 10 17 40 22 362 152 46 27 20 18 18 16 16 42 28 21 19 1057 35.2 362 10 2100 2.33 2.60 , BY HATER YEAR (WY) 36.4 111 1973 3.32 1984 FOR 1993 12219 33 705 5 6 8860 17 24240 2 30 65 17 8 47.5 157 1986 3.20 1977 WATER YEAR .4 .5 Apr 11 .5 Mar 22 .0 Apr 1 Apr 11 .17 Apr 11 .22 .10 .2 15.5 44.4 1987 2.26 1977 12.6 34.6 1979 2.93 1977 HATER 29 56 13 2370 1 1 13600 19 21310 1 26 50 14 6 17.0 50.8 1979 3.44 1978 YEARS 1969 - .4 .5 .6 May 18 .3 Jul 24 .4 Jul 20 Nov 7 .80 Nov 7 .95 .47 .0 26.8 73.2 1979 6.54 1978 1993 1971 1984 1985 1977 1977 1979 1979 707 RIO CIBUCO BASIN 50038320 RIO CIBUCO BELOW COROZAL, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1969-76, 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 07. .. DEC 23... FEB 1993 05. .. APR 14. .. HAY 25... SEP 02. .. TIME 0905 0825 0900 0930 0855 1140 DIS- CHARGE, INST. CUBIC FEET PER SECOND 9.5 21 153 53 43 9.8 SPE- CIFIC CON- DUCT- ANCE (US/CM) 392 333 359 262 291 324 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.0 7.2 8.0 7.3 7.1 7.4 TEMPER- ATURE WATER (DEQ C) 26.0 23.0 21.0 22.5 24.0 25.0 TUR- BID- ITY (NTU) 5.0 -- 7.1 89 16 1.0 OXYGEN, DIS- SOLVED (MG/L) 5.9 6.6 6.0 8.2 7.5 7.9 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 72 77 56 89 67 72 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) <10 — 43 15 30 <10 COLI- FORM, FECAL, 0.45 UM-MP (COLS./ 100 ML) K1200 5000 4600 K19000 K13000 3400 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 540 4900 5100 3600 K12000 2400 DATE OCT 1992 07. .. DEC 23... FEB 1993 05... APR 14. .. MAY 25... SEP 02... HARD- NESS TOTAL (MG/L AS HARD- NESS NONCARB CALCIUM WH WAT TOT FLD CAC03) CACO3 83 98 140 DIS- SOLVED MG/L AS (MG/L 20 24 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS NA) 8.1 11 9.2 13 SODIUM AD- SORP- TION RATIO POTAS- SIUM, DIS- SOLVED AS K) 36 12 22 0.5 2.4 0.6 4.2 0.8 3.3 ALKA- LINITY WAT WH TOT FET SULFIDE FIELD CACO3 79 120 130 94 98 98 TOTAL (MG/L MG/L AS (MG/L SULFATB DIS- SOLVED (MG/L CHLO- RIDE, DIS- SOLVED (MG/L AS S) AS SO4) AS CL) <0.5 7.7 14 <0.5 17 16 16 24 DATE OCT 1992 07.. . DEC 23. .. FBB 1993 05... APR 14.. . MAY 25.. . SEP 02.. . FLUO- RIDE, DIS- SOLVED (MG/L AS F) 0.20 -- -- 0.10 -- 0.10 SILICA, DIS- SOLVED (MG/L AS SI02) 21 -- — 23 -- 34 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 132 -- -- 163 -- 206 SOLIDS, DIS- SOLVED (TONS PER DAY) 3.39 -- — 23.3 -- 5.46 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 4 17 <1 86 24 4 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 2.25 -- -- 1.25 — -- NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.050 <0.010 <0.010 0.050 <0.010 <0.010 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 2.30 0.360 0.300 1.30 0.170 0.270 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.110 0.020 0.020 0.070 0.080 0.030,. NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.39 -- -- 0.53 0.72 — K - non-ideal count 108 RIO CIBOCO BASIN 50038320 RIO CIBOCO BELOW COROZAL, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 07... DEC 23... FBB 1993 05... APR 14... MAY 25... SEP 02... DATE OCT 1992 07.. . DEC 23... FBB 1993 05... APR 14... MAY 25... SEP 02.. . 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) 2.8 — — 1.9 0.97 — LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N03) 12 -- -- 8.4 4.3 -- MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.540 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 (UG/L AS B) 30 — -- 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) 8 -- -- 12 -- -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CO) 20 — — 20 — -- MBTHY- LBNB BLUB ACTIVE SUB- STANCE (MG/L) 710 2400 140 120 <0.10 <0.10 20 20 <0.010 <0.010 0.01 0.03 709 RIO CIBUCO 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) downstream from Rio Indio, and 0.8 mi (1.3 km) east of Vega Baja. DRAINAGE AREA.--99.1 mi* (256.7 km2 ), of which 25.4 mi a (65.8 km 1 ), does not contribute directly to surface runoff. WATER-DISCHARGE RECORDS PERIOD OP RECORD.—January 1973 to current year. GAGE.—Water-stage recorder. Datum of gage is 7.79 ft (2.374 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. EXTREMES OUTSIDE PERIOD OP RECORD.--Flood of Dec. 11, 1965 reached a stage of 26.2 ft (7.99 m), datum unknown, discharge about 28,000 ftVs (793 mVs) . DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN PEB MAR APR MAY JUN JUL AU6 SEP 1 92 26 2 64 24 3 205 27 4 53 452 5 81 234 6 66 97 7 38 61 8 33 49 9 34 53 10 29 51 11 48 41 12 30 36 13 27 151 14 26 344 15 25 62 16 24 59 17 54 65 18 90 52 19 133 48 20 41 56 21 30 125 22 29 54 23 52 135 24 58 92 25 41 71 26 31 49 27 40 624 28 28 952 29 26 793 30 47 537 31 29 TOTAL 1604 5420 MEAN 51.7 181 MAX 205 952 MIN 24 24 AC-PT 3180 10750 CFSM .52 1.82 IN. .60 2.03 STATISTICS OF MONTHLY MEAN MEAN 165 189 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 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 e Estimated 222 159 122 109 93 70 66 58 e54 e60 e57 e57 e70 e98 el!2 e58 e70 e60 e62 e62 e57 e!79 187 225 464 1110 792 e536 e460 392 232 6353 205 1110 54 12600 2.07 2.38 DATA 185 1316 1982 30.5 1979 POR 175 144 125 114 101 157 250 146 114 98 88 90 84 81 72 66 65 60 55 53 53 60 149 69 88 76 59 57 62 115 122 3048 98.3 250 53 6050 .99 1.14 250 e65 e52 e52 e51 eSO eSO eSO 49 48 47 47 47 44 43 43 65 49 50 123 187 91 66 60 56 55 56 56 ___ ___ —— 1902 67.9 250 43 3770 .69 .71 FOR WATER YEARS 1973 96.6 209 1988 36.3 1984 91.1 190 1988 32.6 1977 57 56 53 50 48 46 45 42 42 41 41 41 38 36 35 53 80 54 41 36 35 34 33 70 50 38 35 35 36 40 69 1410 45.5 80 33 2800 .46 .53 - 1993 93.5 339 1990 24.3 1984 1992 CALENDAR YEAR 36541 99.8 2930 19 22 72480 1.01 13.72 210 42 25 Jan 6 May 15 May 9 39 31 30 30 29 28 28 48 239 259 502 1040 312 682 632 511 381 152 104 216 775 513 181 120 97 76 122 392 1610 3260 --- 12439 415 3260 28 24670 4.18 4.67 549 934 452 289 226 478 1260 623 1190 515 444 337 273 325 245 333 294 216 193 181 199 189 623 443 429 360 399 297 232 204 218 12950 418 1260 181 25690 4.22 4.86 193 154 140 127 118 108 110 115 114 107 109 87 83 84 79 79 73 68 135 196 105 89 88 78 73 65 64 62 107 109 --- 3119 104 196 62 6190 1.05 1.17 78 77 101 80 58 53 68 103 59 53 225 245 84 63 54 53 49 47 48 49 50 77 136 264 174 176 226 119 93 90 84 3136 101 264 47 6220 1.02 1.18 80 77 73 71 69 71 65 62 62 68 60 60 58 59 63 171 138 69 60 55 54 52 63 51 49 49 46 47 62 56 58 2078 67.0 171 46 4120 .68 .78 55 53 47 45 59 67 102 81 48 56 55 43 51 45 41 206 115 482 598 320 117 82 79 180 79 95 90 217 118 119 --- 3745 125 598 41 7430 1.26 1.41 , BY WATER YEAR (WY) 172 671 1987 16.2 1984 POR 1993 57204 157 3260 24 30 12900 17 22 113500 1 21 385 70 39 220 655 1985 24.7 1977 WATER YEAR Apr 30 Oct 16 Oct 28 Apr 30 .35 Apr 30 Nov 2 .58 .47 78.2 245 1987 12.8 1977 56.2 162 1979 15.5 1977 WATER 130 236 49 14600 7 8 34000 19 14 94230 1 17 232 61 26 84.4 461 1979 21.2 1978 YEARS 1973 - .3 Dec 13 .4 Jul 24 .5 Jul 21 Apr 12 .10 Apr 12 Jul 24 .31 .83 121 450 1979 27.3 1991 1993 1982 1974 1981 1977 1977 1987 1987 1977 RIO CIBUCO BASIN 50039500 RIO CIBUCO AT VEGA BAJA, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.—Water years 1972 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 02. .. DEC 09. .. FBB 1993 08... APR 19... JUN 07... SEP 15. .. DATE OCT 1992 02... DEC 09... FBB 1993 08... APR 19. .. JON 07... SEP 15... TIME 1110 1040 1040 1200 1125 1300 HARD- NESS TOTAL (MG/L AS CAC03) 160 — -- 170 -- 170 DIS- CHARGE, INST. CUBIC FEET PER SECOND 41 55 52 114 104 44 HARD- NESS NONCARB WH WAT TOT FLD MG/L AS CACO3 17 -- -- 23 -- 14 SPE- CIFIC CON- DUCT- ANCE (US/CM) 413 474 439 404 413 357 CALCIUM DIS- SOLVED (MG/L AS CA) 52 -- — 54 -- 54 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.4 7.2 7.7 7.4 7.6 7.6 MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) 7.6 -- -- 8.9 -- 9.4 TEMPER- ATURE WATER (DBG C) 27.0 24.0 24.5 24.5 27.0 28.0 SODIUM, DIS- SOLVED (MG/L AS NA) 14 -_ _- 12 __ 18 TUR- BID- ITY (NTU) 50 17 5.2 29 12 1.4 SODIUM AD- SORP- TION RATIO 0.5 -- __ 0.4 __ 0.6 OXYGEN, DIS- SOLVED (MG/L) 5.2 3.7 4.6 6.9 6.9 7.2 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 5.1 -- — 3.8 — 3.2 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 64 43 54 81 85 91 ALKA- LINITY WAT WH TOT FBT FIELD MG/L AS CAC03 150 200 190 160 170 150 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 14 25 17 15 15 <10 SULFIDB TOTAL (MG/L AS S) <0.5 -- -- <0.5 -- -- COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 3300 450 420 730 440 390 SULFATB DIS- SOLVED (MG/L AS S04) 17 -- -- 20 -- 13 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 970 710 260 2600 64 150 CHLO- RIDE, DIS- SOLVED (MG/L AS CL) 24 — -- 20 -- 22 DATE OCT 1992 02... DEC 09... FBB 1993 08... APR 19.. . JUN 07.. . SEP 15.. . FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.20 -- -- 0.10 -- 0.10 SILICA, DIS- SOLVED (MG/L AS SI02) 15 -- -- 19 -- 20 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 225 -- -_ 234 -- 230 SOLIDS, DIS- SOLVED (TONS PER DAY) 25.1 -- _- 71.9 -- 27.3 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) <1 10 16 27 11 9 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 1.51 1.42 1.21 1.18 1.23 1.11 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.090 0.080 0.090 0.020 0.070 0.090 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 1.60 1.50 1.30 1.20 1.30 1.20 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.130 0.130 0.210 0.080 0.100 0.180 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.47 0.57 0.89 0.62 1.6 0.52 K = non-ideal count DATE OCT 1992 02... DEC 09.. . FEB 1993 08.. . APR 19... JUN 07... SEP 15... DATE OCT 1992 02... DEC 09... FEB 1993 08.. . APR 19... JUN 07.. . SEP 15... RIO CIBOCO BASIN 50039500 RIO CIBUCO AT VEGA BAJA, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 111 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.60 0.70 1.1 0.70 1.7 0.7 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) 2.2 1.9 2.4 1.9 3.0 1.9 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N03) 9.7 10 11 9.8 13 8.4 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.360 0.260 0.260 0.080 0.280 0.190 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) 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) 2 -- -- 4 -- -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) 10 — — 10 — -- METHY- LENE BLUE ACTIVE SUB- STANCE (MG/L) 1700 1500 60 110 <0.10 <0.10 <0.010 •cO.010 0.05 0.04 112 THIS PAGE WAS LEFT BLANK INTENTIONALLY 113 Drosnoge boundaries -n hrne&tone terrors* .4 NARANJ \'J f/"*"?** \ } -^ §i Q4483Q? fX 1 •' !-S ;< f ! ' SV} J> »<© Cit'y'JO OOlMfi ) 0 ( /V •--._ r\M /1 /_ >-*«^^* v -~^J ; Rio Gi-O'ids d* Mooo^i' bos n v EXPLANATION A 0460 SURFACE-WATER STATION AND NUMBER W 0430 QUALITY-OF-WATER STATION AND NUMBER \70399 QUALITY-OF-WATER PARTIAL RECORD STATION AND NUMBER 0 216 WELL AND WELL NUMBER • 039990 LAKE-ELEVATION STATION 0123456 KILOMETERS 01 234 MILES .039950 -A-/W/ i-i?? _>V^. -T3,',.'<> ^. . f L ; . -X r—• ~.<s yrana* \-.,- (/ --039990 N a* POL-IBI V-- ;^t ' •- \ k r Figure 18.--Rio de la Plata basin. 114 RIO DE LA PLATA BASIN 50039990 LAGO CARITE AT GATE 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 Escuela 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 Escuela Segunda Unidad. DRAINAGE AREA.—8.20 mi 3 (21.24 km3 ). 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 demands 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 has a capacity of approximately 11,310 acre-feet (13.9 hm3 ). 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 1,782.22 ft (543.22 m), July 24; minimum elevation, 1,766.95 ft (538.57 m), Apr. 29. Capacity Table (based on Data from Puerto Rico Electric Power Authority) Contents, in acre-feet Elevation, in feet Elevation, in feet 1,746 1,760 1,769 0 2,471 4,561 1,775 1,780 1,790 Contents, in acre-feet 6,194 7,704 11,048 ELEVATION (FEET NGVD), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY OBSERVATION AT 24iOO VALUES DAY OCT NOV JAN FEE MAR APR 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 1780.71 1780.58 1780.44 1780.33 1780.19 1780.12 1780.00 1779.88 1779.78 1779.62 1779.51 1779.37 1779.24 1779.08 1778.94 1778.81 1778.70 1778.54 1778.47 1778.31 1778.17 1778.04 1777.87 1777.76 1777.67 1777.49 1777.35 1777.25 1777.12 1777.01 1776.84 1778.81 1780.71 1776.84 1776.73 1776.59 1776.43 1776.43 1776.28 1776.31 1776.23 1776.09 1775.96 1775.82 1775.67 1775.53 1775.40 1775.23 1775.19 1775.07 1774.93 1774.91 1774.81 1774.85 1774.84 1774.81 1774.73 1774.71 1774.58 1774.45 1774.82 1774.97 1775.00 1775.20 1775.42 1776.73 1774.45 1775.35 1775.28 1775.31 1775.26 1775.18 1775.06 1774.96 1774.86 1774.73 1774.59 1774.49 1774.35 1774.25 1774.14 1774.01 1774.06 1774.02 1773.91 1773.84 1773.76 1773.68 1773.64 1773.57 1773.51 1773.45 1773.59 1773.57 1773.50 1773.47 1773.45 1773.45 1774.20 1775.35 1773.45 1773.53 1773.53 1773.51 1773.47 1773.43 1773.44 1773.48 1773.42 1773.41 1773.40 1773.35 1773.29 1773.23 1773.17 1773.12 1773.03 1772.99 1772.92 1772.86 1772.79 1772.71 1772.77 1772.71 1772.66 1772.69 1772.65 1772.70 1772.81 1773.66 1773.66 1773.66 1773.16 1773.66 1772.65 1773.62 1773.61 1773.54 1773.48 1773.43 1773.38 1773.32 1773.25 1773.16 1773.11 1773.05 1773.12 1773.06 1772.98 1772.94 1772.85 1772.69 1772.59 1772.50 1772.39 1772.28 1772.14 1772.03 1772.01 1771.92 1771.86 1771.78 1771.69 ___ ___ --- 1772.78 1773.62 1771.69 1771.50 1771.53 1771.42 1771.35 1771.35 1771.27 1771.20 1771.14 1771.08 1771.02 1770.97 1770.89 1770.86 1770.79 1770.68 1770.59 1770.50 1770.42 1770.38 1770.32 1770.22 1770.12 1770.03 1769.93 1769.84 1769.75 1769.64 1769.55 1769.46 1769.37 1769.25 1770.53 1771.53 1769.25 1769.16 1769.05 1768.95 1768.82 1768.72 1768.60 1768.49 1768.43 1768.49 1768.41 1768.31 1768.20 1768.27 1768.21 1768.13 1768.03 1767.97 1767.87 1767.80 1767.74 1767.64 1767.53 1767.43 1767.38 1767.26 1767.17 1767.11 1767.03 1767.46 1767.43 —— 1768.04 1769.16 1767.03 1767.47 1768.04 1768.04 1767.94 1767.95 1767.86 1767.73 1767.64 1767.56 1767.45 1767.32 1767.21 1767.13 1768.19 1768.16 1768.07 1767.98 1767.92 1767.82 1767.74 1767.86 1767.84 1767.84 1767.78 1767.90 1767.89 1767.87 1767.87 1767.86 1767.86 1767.84 1767.79 1768.19 1767.13 1767.86 1767.85 1767.72 1767.69 1767.66 1767.58 1767.56 1767.52 1767.44 1767.46 1767.42 1767.37 1767.37 1767.51 1768.04 1768.10 1768.14 1769.78 1772.82 1773.49 1773.63 1773.96 1774.11 1774.18 1774.32 1774.42 1774.50 1774.57 1774.64 1774.71 —— 1770.31 1774.71 1767.37 1774.73 1774.83 1775.07 1775.12 1775.15 1775.16 1775.30 1775.35 1775.25 1775.23 1781.91 1781.82 1781.73 1781.51 1781.53 1781.53 1781.45 1781.41 1781.42 1781.42 1781.41 1781.97 1781.90 1782.02 1781.77 1781.67 1781.61 1781.56 1781.50 1781.46 1781.45 1779.52 1782.02 1774.73 1781.41 1781.40 1781.38 1781.37 1781.34 1781.34 1781.32 1781.30 1781.27 1781.26 1781.26 1781.23 1781.21 1781.17 1781.25 1781.89 1781.72 1781.62 1781.55 1781.49 1781.44 1781.43 1781.52 1781.50 1781.45 1781.42 1781.38 1781.33 1781.27 1781.27 1781.21 1781.39 1781.89 1781.17 1781.19 1781.15 1781.11 1781.06 1781.08 1781.05 1781.01 1780.97 1780.99 1781.02 1780.98 1780.92 1780.87 1780.83 1780.83 1780.83 1780.78 1780.75 1780.66 1780.63 1780.59 1780.55 1781.19 1781.21 1781.19 1781.14 1781.15 1781.17 1781.18 1781.50 —— 1780.99 1781.50 1780.55 RIO DE LA PLATA BASIN 50043000 RIO DE LA PLATA AT PROYECTO LA PLATA, PR 775 LOCATION.--Lat 18°09'37", long 660 13'44", Hydrologic Unit 21010005, at upstream side of bridge on Highway 173, 0.4 ml (0.6 km) northeast of Proyecto La Plata, and 2.5 ml (4.0 km) upstream from Rio Usabon. DRAINAGE AREA.--63.0 mi 1 (163.2 km'), excludes 8.2 mi a (21.1 km 1 ) upstream from Carite Reservoir, the flow of which is diverted to Rio Guamani. WATER-DISCHARGE RECORDS PERIOD OP RECORD.—1958 (occasional measurements only), February 1959 to March 1960 (monthly measurements only). April 1960 to current year. GAGE.--Water-stage recorder. Elevation of gage is 850 ft (259 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 ft'/s (0.65 mVs) into Cidra Reservoir. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 e35 el? 2 e27 e!6 3 e23 e!7 4 e20 e!8 5 e80 e21 6 e200 e!9 7 e!20 e27 8 e35 e22 9 e27 e!7 10 e25 e!6 11 e23 e24 12 e21 e!9 13 e20 e30 14 e21 e25 15 e20 e20 16 e!9 e20 17 e21 e!8 18 e40 e22 19 e35 e25 29 e55 e!60 21 e30 e70 22 e25 e55 23 e22 e65 24 e!70 e35 25 e!40 e25 26 e35 e24 27 e22 e600 28 el 8 e700 29 e20 e200 30 e23 e250 31 e!7 TOTAL 1389 2577 MEAN 44.8 85.9 MAX 200 700 MIN 17 16 AC-FT 2760 5110 CFSM .82 1.57 IN. .94 1.75 STATISTICS OF MONTHLY MEAN MEAN 207 181 MAX 2164 831 (WY) 1971 1978 MIN 7.82 12.1 (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 FLOW INSTANTANEOUS PEAK STAGE ANNUAL RUNOFF (AC- FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS elOO e80 e65 e70 e50 e45 e42 e40 e37 e37 e36 e35 e36 e37 e60 e40 e41 e42 e41 e38 e37 e40 e45 e42 e50 e330 e!70 e70 e40 e32 e30 1858 59.9 330 30 3690 1.09 1.26 DATA 101 565 1971 9.16 1990 FOR e35 e42 e33 e30 e28 e27 e40 e47 e42 e35 e33 e31 e30 e27 e26 e25 e24 e23 e22 e21 e20 el9 e35 e27 e25 e28 e25 e90 e300 elOO e60 1350 43.5 300 19 2680 .79 .92 FOR WATER 66.1 519 1992 7.78 1990 e30 e25 e22 e20 el8 el6 el5 el4 el4 e!3 el2 el2 el2 e!2 e!3 el2 el2 el3 e!3 el3 e!4 el4 el5 el5 el5 e!4 e!4 e!3 __- --- 425 15.2 30 12 843 .28 .29 YEARS 1960 45.7 195 1989 7.65 1990 el3 e!3 e!3 e!2 el2 el2 ell ell ell elO elO e9.8 e9.8 e9.6 elO ell ell elO e9.8 e9.6 e9.4 e9.2 e9.2 e9.4 e9.5 e9.6 e9.0 e9.0 e8.8 e8.6 e8.5 318.8 10.3 13 8.5 632 .19 .22 - 1993 33.9 120 1972 4.72 1977 1992 CALENDAR YEAR 29500. 80. 8000 7. 7. 58510 1. 20. 75 19 9. 2 6 Jan 5 1 Sep 13 7 Sep 9 47 03 4 e8.5 e9.0 e9.0 e9.0 e9.0 e8.6 e8.2 el5 e35 e60 e80 e55 e90 elOO e70 e90 e50 e65 e35 e25 e28 e22 el8 el 5 el4 el3 el3 e30 e300 e250--- 1534.3 51.1 300 8.2 3040 .93 1.04 e!70 e330 e80 e45 e35 e32 e30 e28 e45 e35 e30 e27 e25 e230 e70 e40 e32 e27 e24 e23 e22 e21 e65 e70 e45 elOO e50 e37 e30 e25 e21 1844 59.5 330 21 3660 1.09 1.25 e!9 e!9 e!8 el6 e!5 e!4 e!4 e!3 e!3 e!4 el4 e!4 e!5 e!6 e20 e50 e70 e50 e300 e450 eSOO el50 el70 e70 e55 e45 e35 e32 e28 e25 --- 2264 75.5 500 13 4490 1.38 1.54 e30 e25 e27 e35 e30 e27 e25 e24 e26 e23 e!200 eSOO e200 e70 e40 e34 e31 e30 e30 e33 e45 e200 e550 e!40 e!30 e80 e60 650 642 e38 e35 3810 123 1200 23 7560 2.24 2.59 e32 e30 e29 e28 e27 e26 e25 e24 e24 e23 e22 e23 e22 621 621 e450 e!70 e80 e35 e30 e27 e27 e40 e28 e25 e23 e22 621 e40 e30 e24 1449 46.7 450 21 2870 .85 .98 621 e20 e!9 e!9 e90 elOO e!20 e50 e30 e25 e35 e25 621 e!9 e 17 621 e25 e30 e35 e25 e35 e23 6300 6200 elOO e50 e27 e23 e40 e42 1587 52.9 300 17 3150 .97 1.08 , BY WATER YEAR (WY) 50.7 323 1971 6.61 1977 FOR 1993 20406 55 1200 8 8 40480 1 13 100 27 12 105 594 1985 6.66 1968 WATER YEAR .1 .9 Jul 11 . 2 Apr 7 . 8 Apr 1 .02 .85 94.7 629 1970 4.93 1977 85.0 489 1961 5.30 1977 WATER 103 368 31 20300 2 3 73600 36 74720 1 25 159 29 9 135 642 1961 9.45 1967 YEARS 1960 - .3 Sep 6 .6 Jul 25 .2 Jul 6 Jan 5 .39 Jan 5 .88 .57 .0 154 975 1960 11.9 1967 1993 1971 1968 1960 1974 1977 1992 1992 e Estimated 776 RIO DE LA PLATA BASIN 50043000 RIO DB LA PLATA AT PROYBCTO LA PLATA, PR—Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1958 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 08... DEC 03... FEB 1993 11... APR 13... JUN 08. .. ADG 31. .. DATE OCT 1992 09. .. DEC 03... FBB 1993 11... APR 13... JUN 08... ADG 31... TIME 0955 0840 0910 0900 0935 1315 HARD- NESS TOTAL (HQ/L AS CAC03) 94 -- -- 150 -- 150 DIS- CHARGE, INST. CUBIC FEET PER SECOND 29 50 12 15 13 23 HARD- NESS NONCARB WH WAT TOT FLD MG/L AS CAC03 4 -- -- 0 -- 3 SPE- CIFIC CON- DUCT- ANCE (US/CM) 272 315 484 424 570 387 CALCIUM DIS- SOLVED (MG/L AS CA) 24 -- — 37 -- 34 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.3 6.6 7.8 7.5 7.7 7.9 MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) 8.3 __ -- 14 -- 15 TEMPER- ATURE WATER (DBG C) 26.5 25.0 24.0 24.5 27.5 31.0 SODIUM, DIS- SOLVED (MG/L AS NA) 19 __ — 34 37 TUR- BID- ITY (NTU) 56 71 4.9 5.2 3.5 0.30 SODIUM AD- SORP- TION RATIO 0.9 __ -- 1 -- 1 OXYGEN, DIS- SOLVED (MG/L) 6.0 5.6 4.2 6.2 7.6 7.0 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 2.6 __ — 2.9 -- 2.6 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 75 68 50 75 97 93 ALKA- LINITY WAT WH TOT FBT FIELD MG/L AS CACO3 95 110 160 150 120 120 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 17 12 17 13 <10 16 SULFIDB TOTAL (MG/L AS S) <0.5 -- -- <0.5 -- -- COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 2700 410 K130 K710 K130 1700 SULFATE DIS- SOLVED (MG/L AS S04) 12 -- -- 19 -- 43 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 520 640 K190 68 220 60 CHLO- RIDE, DIS- SOLVED (MG/L AS CL) 16 -- -- 31 -- 190 SOLIDS, RESIDUE DATE OCT 1992 08... DEC 03.. . FEB 1993 10... APR 13.. . JUN 08.. . AUG 31.. . FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.20 -- -- 0.20 -- 0.20 SILICA, DIS- SOLVED (MG/L AS SI02) 18 -- -- 23 -- 22 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 156 -- -- 251 -- 416 SOLIDS, DIS- SOLVED (TONS PER DAY) 12.2 -- -- 10.2 -- 25.8 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 34 10 7 43 <1 <1 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.710 0.940 1.88 1.09 1.26 0.950 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.070 0.060 0.020 0.110 0.040 0.050 NITRO- GEN, N02+N03 TOTAL (MG/L AS N) 0.780 1.00 1.90 1.10 1.30 1.00 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.160 0.020 0.020 0.120 0.050 0.040 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.44 0.48 0.68 0.48 0.55 0.66 non-ideal count RIO DE LA PLATA BASIN S0043000 RIO DE LA PLATA AT PROYBCTO LA PLATA, PR—Continued WATER-QOALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 117 DATE OCT 1992 08... DEC 03.. . FEE 1993 10... APR 13... OUN 08... AUG 31.. . DATE OCT 1992 08.. . DEC 03... FEB 1993 10.. . APR 13.. . JUN 08... AUG 31... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.60 0.50 0.70 0.60 0.60 0.70 IRON, TOTAL RECOV- ERABLE (UG/L AS FE) 2500 -- -- 330 -- -- NITRO- GEN, TOTAL (MG/L AS N) 1.4 1.5 2.6 1.8 1.9 1.7 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) <1 -- -- <1 -- -- NITRO- GEN, TOTAL (MG/L AS NO3) 6.1 6.6 12 8.0 9.2 7.5 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) 70 -- -- 60 -- -- PHOS- PHORUS TOTAL (MG/L AS P) 0.300 0.280 0.590 0.360 0.350 0.350 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) <0.10 -- -- <0.10 -- -- BARIUM, TOTAL ARSENIC RECOV- TOTAL BRABLE (UG/L (UG/L AS AS) AS BA) <1 <100 __ __ 1 <100 __ -- -- SILVER, SELE- TOTAL NIUM, RBCOV- TOTAL ERABLE (UG/L (UG/L AS SE) AS AG) <1 <1 __ __ <1 <1 __ __ BORON, TOTAL RECOV- ERABLE (UG/L AS B) 40 -- -- 60 -- — — ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) 20 __ -- <10 -- -- CHRO- CADMIUM MIUM, TOTAL TOTAL RBCOV- 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) <0.010 1 __ __ <0.010 3 — — COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) <10 -- — 10 -- — — MBTHY- LENE BLUE ACTIVE SUB- STANCE (MG/L) 0.03 — -- 0.06 -- — 118 RIO DB LA PLATA BASIN 50043800 RIO DB LA PLATA AT COMERIO, PR LOCATION.--Lat 18O 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 AREA.--109 mi' (282 km>). HATER-DISCHARGE RECORDS PERIOD OP RECORD.--December 1988 to current year. GAGE.—Hater-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, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN PBB MAR APR MAY JUN JUL AUG SEP 1 69 31 2 52 30 3 44 31 4 38 34 5 175 40 6 670 35 7 326 52 8 86 41 9 63 31 10 50 30 11 43 46 12 40 35 13 38 56 14 39 48 15 38 37 16 36 38 17 41 34 18 78 41 19 62 47 20 107 328 21 53 154 22 43 98 23 41 125 24 322 69 25 256 48 26 69 43 27 41 1100 28 33 1380 29 29 389 30 43 503 31 32 TOTAL 3057 4974 MEAN 98.6 166 MAX 670 1380 MIN 29 30 AC-PT 6060 9870 CPSM .91 1.53 IN. 1.05 1.71 STATISTICS OP MONTHLY MEAN MEAN 281 96.9 MAX 866 166 (NY) 1991 1993 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 PLOW 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 194 146 120 128 105 92 83 76 71 71 69 67 67 72 107 81 77 81 79 73 71 72 83 79 81 636 316 98 69 57 54 3475 112 636 54 6890 1.03 1.19 DATA 58.1 112 1993 23.9 1990 FOR 65 78 63 59 54 51 77 83 60 54 49 47 46 43 44 44 42 41 40 41 40 41 68 53 46 54 48 61 610 180 109 2391 77.1 610 40 4740 .71 .82 99 64 58 54 48 44 39 37 36 36 36 36 36 38 34 33 33 32 32 33 34 34 33 31 30 30 28 28 ___ ___ --- 1106 39.5 99 28 2190 .36 .38 FOR WATER YEARS 1989 192 732 1992 22.8 1990 96.3 247 1989 24.4 1990 27 26 26 25 25 24 23 23 21 21 21 20 20 19 20 22 22 22 20 20 20 18 17 18 18 18 17 17 17 16 16 639 20.6 27 16 1270 .19 .22 - 1993 43.0 75.7 1989 20.6 1993 1992 CALENDAR YEAR 53229 145 14600 14 16 105600 1.34 18.25 136 40 21 Jan 5 Hay 11 Hay 8 16 17 17 17 17 16 15 49 90 104 326 192 314 333 263 332 127 165 70 64 72 56 43 37 35 34 32 196 1080 733 --- 4862 162 1080 15 9640 1.49 1.67 411 975 699 179 107 86 79 70 116 96 83 71 59 604 261 113 87 72 66 65 61 63 167 190 110 257 184 107 87 67 59 5651 182 975 59 11210 1.68 1.94 57 56 54 51 47 46 45 46 48 49 47 48 50 48 57 169 85 63 e!620 e!770 e312 373 217 105 79 62 52 49 50 55 5810 194 1770 45 11520 1.78 1.99 50 45 45 61 48 41 38 40 40 37 e3060 el!30 e!31 e64 e50 e44 e43 e43 e43 e43 e67 e217 772 1420 582 250 181 139 113 102 92 9031 291 3060 37 17910 2.69 3.10 83 77 74 71 65 65 63 59 57 55 54 55 53 52 52 1080 369 143 96 77 68 64 99 82 65 57 52 94 107 76 59 3523 114 1080 52 6990 1.05 1.21 52 50 43 44 192 246 337 101 65 60 84 59 48 45 43 49 67 74 92 53 69 51 841 646 121 85 60 53 80 80 3890 130 841 43 7720 1.20 1.33 , BY WATER YEAR (WY) 58.3 162 1993 22.3 1991 FOR 1993 48409 133 3060 15 16 14800 12. 15 96020 1. 16. 262 57 26 110 263 1992 25.3 1989 WATER YEAR Jul 11 Apr 7 Apr 1 Jul 11 85 Jul 11 Apr 6 22 60 71.1 194 1993 16.0 1991 100 291 1993 19.0 1989 HATER 109 133 45. 14600 10 11 127000 29. 10 78920 1. 13. 152 37 17 65.5 114 1993 26.5 1991 YEARS 1989 - 0 Jan 5 Jul 17 Jun 25 Jan 5 22 Jan 5 Aug 28 00 64 214 729 1989 51.2 1991 1993 1993 1990 1992 1989 1989 1992 1992 1990 e Estimated RIO DE LA PLATA BASIN 50043800 RIO DE LA PLATA AT COMERIO, PR—Continued WATER-QUALITY RECORDS PERIOD OF RECORDS.— Water years 1989 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: October 1989 to September 1993. INSTRUMENTATION.-- USD-77 and automatic sediment sampler. REMARKS.—Sediment samples were collected by a local observer on a week basis and during high flow events. EXTREMES FOR PERIOD OF DAILY RECORD.— SEDIMENT CONCENTRATION! Maximum daily mean, 8,800 mg/L Jan. 05, 1992; Minimum daily mean, 2 mg/L few days. SEDIMENT LOADSi 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 WATER YEAR 1993.-- SBDIMENT CONCENTRATION! Maximun daily mean, 1,340 mg/1 June 11, 1993; Minimun daily mean, 2 mg/L several days. SEDIMENT LOADSi Maximun daily mean, el9,000 tons (el7,200 tonnes) July 11, 1993; Minimun daily mean .15 tons (.14 tonnes) Mar. 08, 1993. SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 119 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 (CFS) (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 69 52 44 38 175 670 326 86 63 50 43 40 38 39 38 36 41 78 62 107 53 43 41 322 256 69 41 33 29 43 32 242 128 60 25 98 505 278 134 99 68 48 34 25 19 94 12 8 95 180 74 23 17 16 176 307 165 90 36 27 23 20 48 18 7.4 2.6 190 1740 328 33 18 9.4 5.7 3.6 2.6 2.0 9.8 1.1 .82 36 33 24 3.7 1.9 1.8 500 237 35 11 3.2 2.1 2.7 1.8 31 30 31 34 40 35 52 41 31 30 46 35 56 48 37 38 34 41 47 328 154 98 125 69 48 43 1100 1380 389 503 21 32 49 62 69 75 78 48 24 17 16 14 33 18 16 15 15 15 15 155 117 88 62 30 19 18 544 534 225 297 1.7 2.5 4.3 5.9 7.0 7.2 11 5.7 2.0 1.5 1.9 1.3 10 2.3 1.6 1.5 1.4 1.8 1.8 189 56 22 22 6.1 2.5 2.1 5150 2990 253 449 194 146 120 128 105 92 83 76 71 71 69 67 67 72 107 81 77 81 79 73 71 72 83 79 81 636 316 98 69 57 54 107 86 78 55 35 21 11 5 3 4 4 3 2 15 44 33 15 15 55 105 124 124 124 124 124 445 178 47 28 24 28 62 33 26 19 9.8 5.1 2.5 1.0 .67 .76 .75 .64 .45 3.4 12 7.5 3.1 3.1 11 21 24 24 26 26 27 1760 224 13 5.3 3.7 4.0 TOTAL 3057 3313.22 4974 9214.1 3475 2359.77 120 RIO DE LA PLATA BASIN 50043800 RIO DE LA PLATA AT COMERIO, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) 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 65 78 63 59 54 51 77 83 60 54 49 47 46 43 44 44 42 41 40 41 40 41 68 53 46 54 48 61 610 180 109 34 36 17 12 15 18 33 37 23 15 10 6 24 4 4 4 3 3 4 11 9 6 5 4 4 3 3 17 264 46 75 6.3 8.3 2.9 1.9 2.1 2.4 9.0 8.9 3.8 2.0 1.3 .83 2.9 .48 .48 .47 .40 .33 .48 1.3 .96 .68 .92 .64 .49 .48 .39 42 861 22 25 FEBRUARY 99 64 58 54 48 44 39 37 36 36 36 36 36 38 34 33 33 32 32 33 34 34 33 31 30 30 28 28 —— ___ 48 37 24 11 6 5 5 4 4 3 3 4 4 4 3 4 6 8 10 11 11 12 12 12 12 13 14 14 --- -__ _-_ 14 6.4 3.7 1.6 .84 .66 .52 .45 .38 .34 .34 .38 .43 .47 .32 .35 .53 .74 .88 .94 1.0 1.1 1.1 1.0 .98 1.0 1.1 1.0 --- ___ ___ MARCH 27 26 26 25 25 24 23 23 21 21 21 20 20 19 20 22 22 22 20 20 20 18 17 18 18 18 17 17 17 16 16 13 11 8 6 5 4 3 2 3 4 5 8 11 12 12 12 11 10 8 6 6 9 10 10 10 11 14 16 25 41 59 .93 .74 .57 .45 .33 .25 .18 .15 .20 .22 .30 .46 .57 .61 .63 .69 .67 .54 .43 .32 .35 .45 .46 .47 .48 .49 .62 .73 1.1 1.8 2.6 TOTAL 2391 1011.13 1106 42.55 639 18.79 RIO DE LA PLATA BASIN 50043800 RIO DE LA PLATA AT COMBRIO, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MAY 121 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 (CFS) (MG/L) (TONS/DAY) 16 17 17 17 17 16 15 49 90 104 326 192 314 333 263 332 127 165 70 64 72 56 43 37 35 34 32 196 1080 733 --- APRIL 82 92 74 48 30 19 11 22 41 53 338 491 390 202 145 182 102 144 131 97 85 63 46 34 25 19 15 113 872 463 --- TOTAL 4862 --- e Estimated 3.6 4.2 3.4 2.2 1.4 .81 .42 6.5 13 19 573 288 348 214 179 192 39 73 27 17 15 9.1 5.5 3.4 2.4 1.7 1.3 204 6790 1210 --- 10246.93 411 975 699 179 107 86 79 70 116 96 83 71 59 604 261 113 87 72 66 65 61 63 167 190 110 257 184 107 87 67 59 332 579 455 95 51 17 29 28 52 28 39 46 45 393 129 93 85 80 72 57 40 28 86 104 51 124 104 210 63 55 44 753 2330 1220 51 15 3. 6. 5. 22 7. 8. 8. 7. 1460 114 29 19 15 13 9. 6. 4. 78 68 16 124 60 65 14 9. 7. 8 0 4 0 7 6 4 9 6 8 9 1 MEAN DISCHARGE (CPS) 57 56 54 51 47 46 45 46 48 49 47 48 50 48 57 169 85 63 e!620 e!770 e312 373 217 105 79 62 52 49 50 55 MEAN CONCEN- TRATION (MG/L) JUNE 33 26 28 38 47 48 45 42 38 35 32 29 26 23 22 87 38 27 1340 699 106 205 123 74 72 71 69 68 64 54 SEDIMENT DISCHARGE (TONS /DAY) 5.0 3.9 4.0 5.0 6.0 6.0 5.4 5.1 5.0 4.5 3.9 3.6 3.4 2.9 3.6 52 9.5 4.7 e7290 e5540 e97 322 92 22 15 11 9.4 8.9 8.5 7.6 5651 6551.2 5810 13556.9 122 RIO DE LA PLATA BASIN 50043800 RIO DE LA PLATA AT COMERIO, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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- DISCHARGE TRATION (CFS) (MG/L) 50 45 45 61 48 41 38 40 40 37 e3060 el!30 el31 e64 e50 e44 e43 e43 e43 e43 e67 e217 772 1420 582 250 181 139 113 102 92 JULY 42 33 26 18 14 8 5 4 4 3 863 698 84 58 42 32 23 15 9 6 22 119 439 805 246 35 19 15 13 11 8 TOTAL 9031 --- YEAR e 48409 Estimated SEDIMENT DISCHARGE (TONS/ DAY) MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AUGUST 5.4 4.1 3.2 3.1 1.8 .96 .52 .41 .42 .36 e!9000 e5810 e35 ell e5.7 e3.8 e2.7 el. 7 el.O e.76 e9.5 ellO 1060 4540 549 25 9.5 5.5 4.0 2.9 2.1 31209.43 88525.79 83 77 74 71 65 65 63 59 57 55 54 55 53 52 52 1080 369 143 96 77 68 64 99 82 65 57 52 94 107 76 59 3523 8 8 8 10 11 11 10 7 5 4 4 4 4 9 39 442 222 131 123 117 113 112 111 107 87 58 58 111 116 114 112 —— 1.8 1.7 1.7 1.8 1.9 1.9 1.6 1.1 .76 .59 .58 .58 .56 1.3 5.7 2450 288 52 32 24 20 20 31 25 15 8.7 8.4 29 36 25 17 3104.67 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) SEPTEMBER 52 50 43 44 192 246 337 101 65 60 84 59 48 45 43 49 67 74 92 53 69 51 841 646 121 85 60 53 80 80 109 106 103 100 173 136 200 86 72 61 40 28 25 27 31 35 37 27 33 22 32 26 490 415 65 42 33 24 16 65 15 14 12 12 195 153 376 25 13 9.8 9.3 4.5 3.1 3.3 3.7 4.5 7.2 5.3 8.3 3.2 6.7 3.7 5500 1450 23 9.5 5.3 3.3 3.4 15 3890 7897.1 RIO DE LA PLATA BASIN S0043800 RIO DE LA PLATA AT COMERIO, PR—Continued HATER QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT 123 DATE APR 1993 29.. . 29.. . MAY 01.. . JUN 19... JUL 11.. . 11... DATE APR 1993 29. .. 29... MAY 01... JUN 19... JUL 11... 11... TIME 1630 1720 1815 0620 1445 1510 SED. SUSP. FALL DIAM. PERCENT FINER THAN .016 MM 58 71 76 67 69 24 DIS- CHARGE, INST. CUBIC FEET PER SECOND 1630 4760 1480 2030 13100 14800 SED. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM 70 81 83 76 79 31 SEDI- MENT, SUS- PENDED (MO/L) 5680 3990 2120 2030 5430 21600 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 82 91 96 91 92 41 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 25000 51300 8470 11100 192000 863000 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 92 98 99 98 97 57 SED. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM 29 44 S3 46 41 14 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 97 99 100 99 99 78 SED. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM 40 S3 60 52 49 17 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 99 99. 100 99. 99. 96 SED. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 48 59 64 57 56 19 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 100 6 100 100 5 100 6 100 99 124 RIO DE LA PLATA BASIN 50043800 RIO DE LA PLATA AT COMERIO, PR--Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT DATE OCT 1992 19... APR 1993 05.. . 21... 29.. . 29... 29.. . MAY 01.. . 03.. . JUN 18.. . 19.. . 20... JUL 11.. . 11... AUG 16... TIME 0830 1510 1315 1630 1810 2320 1840 0730 1930 0840 1315 1345 1815 STREAM- FLOW, INSTAN- TANEOUS (CFS) 53 17 58 1630 3450 2220 1520 837 58 1540 1220 5200 5790 SEDI- MENT, SUS- PENDED (MG/L) 360 320 58 734 5930 831 1510 299 3420 1700 191 3690 1460 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 52 15 9.1 3230 55200 4980 6200 676 536 7070 629 51800 25600 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 99 99 91 92 79 94 96 98 91 99 98 86 97 1230 149 2970 1190 73 725 RIO DE LA PLATA BASIN 50044000 RIO DE 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 Comerio plaza. DRAINAGE AREA.--139 mi* (360 km1 ), excludes 8.2 mi* (21.1 km1 ) upstream from Carite Reservoir, the flow of which is diverted to Rio Guamani. PERIOD OF RECORD.—Water years 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 14. .. DEC 08... FEB 1993 04. .. APR 07... MAY 26... SEP 20... TIME 1025 0955 0940 0835 0950 1300 DIS- CHARGE, INST. CUBIC FEET PER SECOND 44 57 75 20 193 86 SPE- CIFIC CON- DUCT- ANCE (US/CM) 358 381 338 418 352 375 PH WATER WHOLE FIELD (STAND- ARD UNITS) 8.0 7.5 8.0 7.9 7.7 7.9 TEMPER- ATURE WATER (DBG C) 26.0 23.5 21.0 24.5 23.5 27.5 TUR- BID- ITY (NTU) 15 19 11 3.1 20 66 OXYGEN, DIS- SOLVED (MG/L) 7.8 7.2 5.4 8.4 8.0 7.6 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 95 84 63 100 96 97 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 15 <10 <10 <10 16 18 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K10000 2700 K740 510 2100 K800 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 3200 K1200 340 K190 2600 K1400 DATE OCT 1992 14. .. DEC 08... FEB 1993 04... APR 07... MAY 26. .. SEP 20... HARD- NESS TOTAL (MG/L AS HARD- NESS NONCARB CALCIUM WH WAT TOT FLD DIS- SOLVED MG/L AS (MG/L CAC03) CAC03 MAGNE- SIUM, DIS- SODIUM, DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS NA) 140 3 34 14 27 160 9 36 16 26 120 0 27 12 18 SODIUM AD- SORP- TION RATIO POTAS- SIUM, DIS- SOLVED AS K) 1.0 2.7 0.9 2.8 0.7 4.0 ALKA- LINITY WAT WH TOT FET SULFIDE FIELD CAC03 130 140 130 160 130 140 TOTAL (MG/L MG/L AS (MG/L SULFATE DIS- SOLVED (MG/L <0.5 17 <0.5 19 13 CHLO- RIDE, DIS- SOLVED (MG/L AS S) AS S04) AS CL) 27 32 19 SOLIDS, RESIDUE DATE OCT 1992 14.. . DEC 08... FEB 1993 04.. . APR 07.. . MAY 26... SEP 20.. . FLUO- RIDE, DIS- SOLVED (MG/L AS F) 0.10 -- -- 0.20 -- 0.20 SILICA, DIS- SOLVED (MG/L AS SI02) 27 -- — 28 — 27 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 233 -- -- 256 -- 191 SOLIDS, DIS- SOLVED (TONS PER DAY) 27.7 -- -- 13.8 -- 44.4 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 3 15 8 1 21 48 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.640 0.980 1.33 1.33 0.710 0.980 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.030 0.020 0.070 0.070 0.090 0.020 NITRO- GEN, N02+N03 TOTAL (MG/L AS N) 0.670 1.00 1.40 1.40 0.800 1.00 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.050 0.030 0.170 0.090 0.170 0.040 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.25 0.57 8.4 1.0 1.7 0.56 non-ideal count 126 DATE OCT 1992 14... DEC 08.. . FEE 1993 04... APR 07... MAY 26... SEP 20... RIO DB LA PLATA BASIN 50044000 RIO DB LA PLATA NEAR COMERIO, PR--Continue WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 BARIUM, BORON, CADMIUM TOTAL TOTAL TOTAL ARSENIC RECOV- RECOV- RECOV- TOTAL BRABLB BRABLB BRABLB (UG/L (UG/L (UG/L (UG/L NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.30 0.60 8.6 1.1 1.9 0.60 NITRO- GEN, TOTAL (MG/L AS N) 0.97 1.6 10 2.5 2.7 1.6 NITRO- GEN, TOTAL (MG/L AS N03) 4.3 7.1 44 11 12 17 PHOS- PHORUS TOTAL (MG/L AS P) 0.180 0.240 0.72 0.200 0.210 0.190 AS AS) AS BA) AS B) <100 <100 50 70 AS CD) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) COPPER, TOTAL RECOV- ERABLE (UG/L AS CO) <1 DATE OCT 1992 14... DEC 08... FEE 1993 04... APR 07... MAY 26... SEP 20.. . IRON, LEAD, TOTAL TOTAL RECOV- RECOV- ERABLE BRABLB (UG/L (UG/L 150 MANGA- NESE, MERCURY TOTAL TOTAL RECOV- ERABLE (UG/L RECOV- ERABLE (UG/L SELE- NIUM, TOTAL (UG/L SILVER, TOTAL RECOV- ERABLE (UG/L ZINC, TOTAL RECOV- CYANIDE BRABLB TOTAL (UG/L (MG/L AS FB) AS PB) AS MN) AS HG) AS SB) AS AG) AS ZN) AS CN) 30 <0.10 <1 <1 PHENOLS TOTAL (UG/L) 20 <0.010 MBTHY- LENE BLUE ACTIVE SUB- STANCE (MG/L) 0.02 127 RIO DE LA PLATA BASIN 50044830 RIO GUADIANA AT GUADIANA, PR LOCATION.—Lat 18°18'08", long 66°13'24", Hydrologic Unit 21010005, at left bank downstream tide of river, 1.3 mi (2.1 km) East of Plaza de Naranjito, 0.9 mi (1.4 km) we«t from intersection of road* 167 and 164 at km 8.9 and 2.9 mi (4.7 km) northwest from Represa Comerio. DRAINAGE AREA.--9.19 mi' (23.80 km'). WATBR-DISCHARGB RECORDS PERIOD OF RECORD.—July 1990 to current year. GAGE.—Water-stage recorder and crest-stage gage. Elevation of gage i« 230 ft (70 m), from topographic map. REMARKS.—Record* fair. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 3.4 3.3 2 2.7 3.2 3 2.5 4.2 4 2.4 28 5 7.0 11 6 6.5 5.3 7 3.4 5.2 8 3.5 4.4 9 3.3 4.2 10 3.6 4.1 11 3.3 2.9 12 3.1 8.6 13 2.9 9.2 14 3.1 8.1 15 2.9 30 16 2.7 17 17 18 8.5 18 23 9.7 19 7.9 8.2 20 3.8 5.8 21 3.0 4.9 22 4.4 33 23 30 17 24 12 11 25 8.3 7.0 26 4.8 6.0 27 4.4 202 28 3.8 59 29 4.3 18 30 4.1 13 31 3.8 TOTAL 191.9 551.8 MEAN 6.19 18.4 MAX 30 202 MIN 2.4 2.9 AC-FT 381 1090 CPSM .67 2.00 IN. .78 2.23 STATISTICS OF MONTHLY MEAN MEAN 36.5 13.3 MAX 98.7 18.4 (WY) 1991 1993 MIN 4.51 7.32 (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 8.6 6.9 5.7 6.1 4.9 5.1 4.2 4.1 4.0 3.8 3.8 3.5 3.1 16 26 7.2 9.7 11 7.2 6.7 5.8 10 7.4 30 40 309 78 93 72 39 22 853.8 27.5 309 3.1 1690 3.00 3.46 DATA 17.6 27.5 1993 5.67 1992 FOR 15 13 12 11 25 18 65 37 18 13 12 12 12 10 9.1 8.6 7.8 7.6 7.2 7.2 6.9 22 16 9.3 11 8.1 6.8 6.7 15 12 24 458.3 14.8 65 6.7 909 1.61 1.86 13 7.7 9.3 7.1 6.3 5.7 5.3 5.0 .8 .7 .5 .6 .5 .1 .1 .1 .4 .6 .2 23 12 8.7 8.0 7.1 6.5 6.6 6.7 6.3 ___ ___ --- 192.9 6.89 23 4.1 383 .75 .78 FOR WATER YEARS 1990 24.2 42.5 1992 14.8 1993 14.9 31.7 1991 6.39 1992 7.1 7.7 6.6 6.1 5.8 5.7 5.4 5.6 5.4 5.2 5.1 5.1 4.9 4.5 4.5 10 7.7 5.7 4.9 4.6 4.5 4.3 6.8 9.9 6.2 .7 .5 .3 .2 .2 .0 175.2 5.65 10 4.0 348 .61 .71 - 1993 10.8 13.7 1992 5.65 1993 1992 CALENDAR YEAR 5596.7 15.3 536 2.4 2.7 11100 1.66 22.65 26 5.1 3.1 Jan 5 Oct 4 Sep 10 3.8 3.6 3.7 3.6 3.9 3.8 3.9 62 26 16 130 30 156 159 124 145 47 17 10 48 64 30 14 10 8.3 6.9 6.3 60 222 155--- 1572.8 52.4 222 3.6 3120 5.70 6.37 268 321 122 50 65 234 149 58 240 97 60 41 29 103 37 27 23 18 16 15 14 29 204 78 81 96 75 51 37 33 31 2702 87.2 321 14 5360 9.48 10.94 25 21 20 18 16 15 15 17 16 21 14 13 14 13 12 11 10 11 63 46 17 19 13 12 11 10 10 34 34 33 --- 584 19.5 63 10 1160 2.12 2.36 15 16 21 14 12 11 30 15 11 11 181 46 20 14 14 12 11 9.7 9.2 9.3 9.7 21 27 92 20 22 16 11 10 9.4 9.2 729.5 23.5 181 9.2 1450 2.56 2.95 8.7 8.4 7.8 7.6 7.7 7.6 7.4 7.3 7.8 7.2 6.9 6.4 6.1 6.3 7.1 78 14 8.3 7.3 6.4 6.2 8.9 8.5 6.3 5.8 5.8 5.7 6.2 6.2 6.1 5.3 295.3 9.53 78 5.3 586 1.04 1.20 4.9 5.1 4.8 4.5 4.7 38 9.4 5.6 5.1 4.9 4.8 4.3 4.4 5.4 6.9 14 9.2 59 100 54 13 9.0 74 32 12 9.8 74 31 15 17 635.8 21.2 100 4.3 1260 2.31 2.57 , BY WATER YEAR (WY) 25.8 52.4 1993 11.6 1991 FOR 1993 8943. 24. 321 2. 3. 2190 9. 17740 2. 36. 61 9. 4. 41.2 87.2 1993 7.49 1991 WATER YEAR 3 5 May 2 4 Oct 4 1 Oct 10 Oct 6 06 Oct 6 67 20 3 1 10.0 19.5 1993 5.21 1991 14.0 23.5 1993 4.51 1992 WATER 19 24 12 536 2 2 6670 13 13750 2 28 33 7 3 7.80 9.53 1993 5.76 1991 YEARS 1990 - .0 .5 .4 Jan 5 .4 Oct 4 .7 Sep 10 Jan 5 .36 Jan 5 .06 .05 .2 .3 11.8 21.2 1993 3.95 1991 1993 1993 1992 1992 1992 1992 1992 1992 RIO DB LA PLATA BASIN 50044830 RIO GUADIANA AT GUADIANA, PR—Continued WATER-QUALITY RECORDS PERIOD OF RECORDS.-- Water years 1990 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE! August 01, 1990 to September 1993. INSTRUMENTATION.-- USD-77 and automatic sediment sampler. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATIONt Maximum daily mean, 1,300 mg/L Oct. 16, 1990; Minimum daily mean, 2 mg/L few days. SEDIMENT LOADSi Maximum daily mean, 18,000 tons (16,300 tonnes) Jan. 05, 1992; Minimum daily mean, 0.00 ton (0.0 tonne) several days. EXTREMES FOR HATER YEAR 1993.-- Water Suspended- sediment concentration (mg/L) Year 1993 1, maximum 090 (May 02) 1 minimum (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 (CFS) 3.4 2.7 2.5 2.4 7.0 6.5 3.4 3.5 3.3 3.6 3.3 3.1 2.9 3.1 2.9 2.7 18 23 7.9 3.8 3.0 4.4 30 12 8.3 4.8 4.4 3.8 4.3 4.1 3.8 MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) OCTOBER 5 4 3 3 12 26 13 8 5 3 3 4 5 4 3 3 39 80 93 40 19 10 936 184 25 15 10 10 10 10 11 (TONS/DAY) .06 .03 .02 .01 .84 .58 .13 .07 .04 .03 .03 .04 .04 .03 .02 .02 5.3 14 2.4 .42 .14 .13 276 5.9 .61 .21 .11 .09 .13 .10 .11 MEAN DISCHARGE (CFS) 3.3 3.2 4.2 28 11 5.3 5.2 4.4 4.2 4.1 2.9 8.6 9.2 8.1 30 17 8.5 9.7 8.2 5.8 4.9 33 17 11 7.0 6.0 202 59 18 13 Suspended -sediment ms 2,920 iximum (May 06) discharge (tons per day) minimum .01 (Several days) , WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 MEAN CONCEN- TRATION (MG/L) NOVEMBER 10 4 7 75 103 47 19 10 9 9 6 16 15 12 73 35 18 23 23 7 6 62 29 19 9 9 724 146 35 18 SEDIMENT DISCHARGE (TONS/DAY) .08 .04 .08 9.6 3.6 .68 .27 .11 .09 .10 .05 1.5 .44 .26 16 2.6 .45 .60 .54 .11 .09 9.2 1.6 .69 .16 .16 1280 30 2.0 .61 MEAN DISCHARGE (CFS) 8.6 6.9 5.7 6.1 4.9 5.1 4.2 4.1 4.0 3.8 3.8 3.5 3.1 16 26 7.2 9.7 11 7.2 6.7 5.8 10 7.4 30 40 309 78 93 72 39 22 MEAN CONCEN- TRATION (MG/L) DECEMBER 8 13 8 9 10 11 9 9 10 16 22 26 14 35 78 41 27 21 14 10 9 18 15 71 90 1280 206 324 154 85 40 SEDIMENT DISCHARGE (TONS/DAY) .21 .24 .14 .16 .13 .17 .11 .10 .10 .16 .23 .25 .13 7.9 9.1 .85 .83 .68 .27 .16 .15 .67 .28 11 13 2420 47 122 35 10 2.4 TOTAL 191.9 307.64 551.8 1361.71 853.8 2683.42 RIO DE LA PLATA BASIN 50044830 RIO GDADIANA AT GOADIANA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) 129 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 15 13 12 11 25 18 65 37 18 13 12 12 12 10 9. 8. 7. 7. 7. 7. 6. 22 16 9. 11 8. 6. 6. 15 12 24 1 6 8 6 2 2 9 3 1 8 7 26 17 9 6 46 35 165 85 30 12 5 6 6 7 10 10 10 5 7 12 18 49 33 19 13 6 4 5 27 20 58 1.1 .58 .30 .19 6.4 2.1 44 10 1.6 .42 .17 .19 .20 .20 .25 .24 .19 .12 .14 .22 .32 4.3 1.8 .45 .39 .15 .07 .09 5.2 .83 17 FEBRUARY 13 7.7 9.3 7.1 6.3 5.7 5.3 5.0 .8 .7 .5 .6 .5 .1 .1 .1 .4 .6 .2 23 12 8.7 8.0 7.1 6.5 6.6 6.7 6.3 36 25 18 16 17 15 15 13 12 11 8 6 5 6 9 9 10 10 11 58 19 13 16 23 28 25 15 11 1.5 .52 .45 .31 .28 .22 .20 .17 .16 .14 .10 .08 .07 .07 .09 .10 .11 .13 .14 8.0 .63 .30 .35 .45 .51 .43 .27 .19 MEAN DISCHARGE (CFS) 7.1 7.7 6.6 6.1 5.8 5.7 5.4 5.6 5.4 5.2 5.1 5.1 4.9 4.5 4.5 10 7.7 5.7 4.9 4.6 4.5 4.3 6.8 9.9 6.2 .7 .5 .3 .2 .2 .0 MEAN CONCEN- TRATION (MG/L) MARCH 11 11 13 12 12 10 10 8 6 6 9 10 10 10 12 17 16 11 7 4 4 4 16 17 9 9 9 10 11 11 8 SEDIMENT DISCHARGE (TONS/DAY) .21 .24 .21 .20 .18 .16 .14 .12 .09 .09 .12 .14 .13 .13 .14 .54 .33 .17 .09 .05 .05 .04 .46 .77 .16 .11 .10 .11 .13 .13 .09 TOTAL 458.3 99.21 192.9 15.97 175.2 5.63 730 RIO OB LA PLATA BASIN S0044830 RIO GUADIANA AT GUADIANA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 MEAN MEAN CONCKN- SEDIMENT MEAN DISCHARGE TRATION DISCHARGE DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) (CFS) 1 2 3 4 5 £ 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 3.6 3,7 3.6 3.9 3.8 3.9 62 26 16 130 30 156 159 124 145 47 17 10 48 £4 30 14 10 8.3 £.9 £.3 £0 222 155 APRIL 9 14 18 20 17 11 10 194 53 31 433 £8 555 619 365 453 109 28 16 133 202 60 19 21 35 27 12 149 809 437 MEAN MEAN CONCEN- SEDIMENT MEAN CONCKN- SEDIMENT TRATION DISCHARGE DISCHARGE TRATION DISCHARGE (MG/L) (TONS/DAY) (CFS) (MG/L) (TONS/DAY) MAY . . • . 194 £. 2. 470 9. 1060 850 336 399 18 1. . 47 77 5. . • . 79 1350 292 - 10 15 18 19 17 10 10 4 4 9 3 48 8 73 52 80 49 21 — 268 321 122 50 £5 234 149 58 240 97 £0 41 29 103 37 27 23 18 16 15 14 29 204 78 81 96 75 51 37 33 31 792 1090 279 45 159 891 364 158 847 237 106 29 28 330 50 16 13 12 11 8 9 62 623 194 209 275 181 111 78 60 67 1250 1220 120 6 72 2920 198 36 1020 £4 18 3 2 298 5 1 20 1480 45 51 94 37 15 8 5 6 .4 - .3 .1 .£ .2 .7fi .56 .43 .32 .34 .0 .1 .9 JUNE 25 21 20 18 16 15 15 17 16 21 14 13 14 13 12 11 10 11 £3 46 17 19 13 12 11 10 10 34 34 33 44 18 13 8 6 5 6 8 9 34 28 30 25 16 10 7 10 20 147 105 25 30 43 45 43 43 43 89 89 95 3.0 1.0 .62 .38 .26 .20 .23 .39 .39 3.7 1.0 1.1 .82 .53 .33 .21 .27 .98 27 17 1.2 1.5 1.6 1.5 1.3 1.1 1.2 19 20 11 TOTAL 1572.8 5202.02 2702 8999.01 584 118.81 RIO DB LA PLATA BASIN 50044830 RIO GOADIANA AT GUADIANA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 131 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 15 16 21 14 12 11 30 15 11 11 181 46 20 14 14 12 11 9.7 9.2 9.3 9.7 21 27 92 20 22 16 11 10 9.4 9.2 729.5 8943.3 JULY 31 27 52 19 10 12 68 25 17 20 684 38 6 8 10 14 23 24 16 49 13 44 63 388 28 38 24 8 6 5 3 ... MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AUGUST 1.3 1.9 4.4 .73 .33 .34 15 1.0 .50 .64 876 7.4 .35 .31 .33 .42 .61 .61 .39 1.5 .55 5.3 6.5 309 1.8 4.8 1.3 .24 .18 .14 .09 1243.96 21739.71 8.7 8.4 7.8 7.6 7.7 7.6 7.4 7.3 7.8 7.2 6.9 6.4 6.1 6.3 7.1 78 14 8.3 7.3 6.4 6.2 8.9 8.5 6.3 5.8 5.8 5.7 6.2 6.2 6.1 5.3 295.3 2 3 5 6 5 4 4 6 13 18 16 9 7 5 14 220 26 11 8 8 8 11 14 6 4 4 4 4 5 8 8 ... .05 .07 .11 .13 .11 .08 .07 .12 .26 .36 .28 .17 .12 .09 .30 92 1.2 .22 .13 .13 .13 .43 .35 .10 .06 .06 .06 .06 .09 .13 .11 97.58 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) SEPTEMBER 4.9 5.1 4.8 4.5 4.7 38 9.4 5.6 5.1 4.9 4.8 4.3 4.4 5.4 6.9 14 9.2 59 100 54 13 9.0 74 32 12 9.8 74 31 15 17 5 4 2 1 1 105 16 5 5 5 4 3 3 3 18 29 16 190 373 117 23 13 565 70 20 16 282 70 26 39 .07 .05 .03 .01 .02 54 .53 .08 .08 .06 .06 .04 .04 .04 1.4 3.9 .86 109 427 25 .87 .31 661 9.4 .70 .40 298 7.5 1.1 3.2 635.8 1604.75 132 RIO DB LA PLATA BASIN 50044830 RIO GUADIANA AT OUADIANA , PR—Continued WATER QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT DATE DEC 1992 26... APR 1993 14... 14. .. MAY 01. .. 06. .. 23... DATE DEC 1992 26. .. APR 1993 14... 14. .. MAY 01. .. 06... 23... TIME 1235 1500 1610 1725 2000 1325 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .016 MM 51 60 38 68 48 57 DIS- CHARGE, INST. CUBIC FEET PER SECOND 593 141 638 1140 1820 624 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM 68 70 67 76 57 70 SEDI- MENT, SUS- PENDED (MG/L) 18800 4820 5170 4770 16100 8110 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 82 84 79 90 70 82 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 30100 1830 8900 14700 79100 13700 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 93 92 89 96 80 94 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM 22 30 31 34 25 23 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 97 97 95 98 86 98 SBD. SUSP. PALL DIAM. PERCENT FINER THAN .004 MM 33 40 38 44 32 37 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 98.6 99 98.7 99 90 99 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 51 60 47 59 37 43 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 100 100 99 100 97 100 RIO DB LA PLATA BASIN 50044830 RIO GO AD I ANA AT GOAD I ANA, PR—Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT 133 DATE NOV 1992 13... DEC 26.. . 26... 28... 28... APR 1993 29... MAY 01.. . 06... 23.. TIME 1735 1255 1650 1325 1450 1900 1540 2115 1455 STREAM- FLOW, INSTAN- TANEOUS (CFS) SEDI- MENT, SUS- PENDED (MG/L) SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 10 1540 500 60 124 619 584 1190 963 95 9810 1040 1150 1330 1390 3250 3750 1950 2.6 40790 1400 186 445 2320 5120 12050 5070 99 70 92 85 76 89 91 75 91 134 RIO DE 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-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 14. .. DEC 08... FBB 1993 04. .. APR 07. .. HAY 26. .. SEP 20. .. DATE OCT 1992 14. .. DEC 08. .. FBB 1993 04. .. APR 07. .. MAY 26. .. SEP 20... DIS- CHARGE, INST. CUBIC FEET TIME PER SECOND 0805 3.3 0750 5.6 0750 9.2 1025 4.2 0810 56 1500 32 HARD- HARD- NESS NESS NONCARB TOTAL WH WAT (MG/L TOT FLD AS MG/L AS CACO3 ) CACO3 130 21 __ __ 150 __ 100 PH OXYGEN, OXYGEN COLI- SPB- WATER DIS- DEMAND, FORM, STRBP- CIFIC WHOLE SOLVED CHEM- FECAL, TOCOCCI CON- FIELD TEMPER- TOR- OXYGEN, (PER- ICAL 0.45 FECAL, DUCT- (STAND- ATURB BID- DIS- CENT (HIGH UM-MF (COLS. ANCB ARD WATER ITY SOLVED SATUR- LEVEL) (COLS./ PER (US/CM) UNITS) (DBG C) (NTU) (MG/L) ATI ON) (MG/L) 100 ML) 100 ML) 398 7.5 24.0 1.2 7.7 90 <10 K1000 2300 360 6.6 22.0 14 3.7 42 13 360 530 351 8.1 21.0 2.7 6.6 75 25 3300 8200 369 7.7 24.5 1.5 7.5 88 <10 430 1300 263 7.5 23.5 18 7.9 96 26 K6600 5100 238 6.6 27.5 40 3.3 41 10 510 4100 ALKA- MAGNB- SODIUM POTAS- LINITY CHLO- CALCIUM SIUM, SODIUM, AD- SIUM, WAT WH SULFATB RIDE, DIS- DIS- DIS- SORP- DIS- TOT FBT SULFIDB DIS- DIS- SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L AS CA) AS MG) AS NA) AS K) CACO3 AS S) AS SO4) AS CL) 31 13 17 0.7 2.3 130 <0.5 17 25 130 140 34 15 19 0.7 2.8 130 <0.5 16 25 130 23 11 14 0.6 2.9 100 -- 15 14 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDB, DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, DIS- SOLVED TDENTS, SOLVED DBG. C, NITRATE NITRITE NO2+N03 AMMONIA ORGANIC SOLVED (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER FENDED (MG/L (MG/L (MG/L (MG/L (MG/L AS F) SIO2) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) OCT 14 DEC 08 FBB 04 APR 07 MAY 26 SEP 20 1992 0.10 27 1993 0.10 25 0.10 23 198 1.76 3 2.29 0.010 2.30 0.040 0.16 12 1.37 0.030 1.40 0.080 0.42 7 1.29 0.010 1.30 0.010 0.69 215 2.44 33 1.59 0.010 1.60 0.020 0.38 25 0.870 0.030 0.900 0.050 0.45 163 14.1 31 1.19 0.010 1.20 0.010 0.39 K = non-ideal count DATS OCT 1992 14... DEC 08... FBB 1993 04... APR 07... MAY 26... SEP 20... DATE OCT 1992 14... DEC 08... FBB 1993 04... APR 07.. . MAY 26... SEP 20... RIO DB LA PLATA BASIN 50044850 RIO GOADIANA NEAR NARANJITO, PR--Continued WATER-QUALITY DATA/ WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 735 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.20 0.50 0.70 0.40 0.50 0.40 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) 2.5 1.9 2.0 1.0 1.4 1.6 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS NO3) 11 8.4 8.9 8.7 6.2 7.1 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.530 0.220 0.170 0.360 0.310 0.190 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 -- -- 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) 5 -- -- <1 -- -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CO) <10 -- — <1 — — MBTHY- LBNB BLUB ACTIVE SUB- STANCE (MG/L) 260 100 30 40 <0.10 <0.10 •cO.010 <0.010 0.05 0.03 136 RIO DE LA PLATA BASIN 50045000 LAGO LA PLATA AT DAHSITE, PR LOCATION.--Lat 18°20'40", long 66°14'10", Hydrologic Unit 21010005, 2.9 mi (4.7 km) at northeast of Plaza de Naranjito, 2.7 mi (4.3 km) West of Road 167, km 15.3, Buena Vista, Bayamdn, 5.2 mi (8.4 km) east of Plaza de Corozal. DRAINAGE AREA.--181 mi' (469 km1 ). ELEVATION RECORDS PERIOD OF RECORD.--February 1989 to current year. GAGE.—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 hm3 ) 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, 166.12 ft (50.63 m), Sept. 23; minimum elevation, 145.86 ft (44.46 m), Apr. 8. 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 1992 TO SEPTEMBER 1993 DAILY OBSERVATION AT 24:00 VALUES DAY OCT NOV DEC JAN FEE MAR APR MAY JUN JUL AUG SEP 1 154.07 154.48 154.99 155.06 154.92 152.52 147.33 159.57 158.06 158.19 161.86 163.47 2 153.98 154.31 155.00 155.10 154.85 152.39 147.09 159.52 158.10 157.97 161.82 163.24 3 153.84 154.32 154.99 155.09 154.84 152.21 146.91 158.65 158.11 157.97 161.81 163.18 4 153.66 154.82 155.03 155.05 154.85 152.04 146.70 158.85 158.06 157.87 161.82 163.12 5 153.55 154.89 155.01 155.10 154.77 151.88 146.47 159.36 157.98 157.73 161.83 163.26 6 155.48 154.82 154.94 155.13 154.71 151.71 146.22 161.16 157.92 157.55 161.12 163.95 7 155.17 154.78 154.88 155.31 154.66 151.53 146.00 159.31 157.88 157.54 161.04 164.21 8 155.00 154.80 154.82 155.05 154.56 151.34 146.27 159.27 157.87 157.45 161.00 164.41 9 154.84 154.74 154.80 154.94 154.47 151.16 147.01 159.26 157.99 157.32 161.01 164.45 10 154.83 154.68 154.75 154.91 154.37 150.98 147.51 157.48 158.07 157.21 160.95 164.34 11 154.70 154.66 154.69 154.91 154.27 150.81 150.36 158.12 158.01 159.34 160.86 164.41 12 154.53 154.64 154.58 154.93 154.18 150.62 152.21 158.46 157.92 159.58 160.76 164.41 13 154.35 154.71 154.51 154.91 154.11 150.43 154.33 158.63 157.90 159.46 160.70 164.38 14 154.24 154.87 154.80 154.89 154.02 150.29 156.81 159.14 157.86 159.40 160.33 164.05 15 154.10 155.10 155.10 154.88 153.91 150.12 157.21 158.26 157.77 159.25 159.29 164.06 16 153.93 154.93 154.97 154.87 153.83 150.07 156.88 158.61 157.93 159.05 162.50 164.09 17 153.83 154.83 154.95 154.86 153.74 150.01 157.34 158.78 158.01 158.88 162.89 164.13 18 154.05 154.85 154.96 154.83 153.64 149.87 157.70 158.84 158.04 158.65 163.27 164.48 19 154.20 154.87 154.98 154.81 153.49 149.72 157.68 158.81 159.60 158.46 163.45 164.85 20 154.42 155.19 154.94 154.79 153.48 149.50 158.16 158.78 158.89 158.22 163.49 164.77 21 154.42 154.94 154.90 154.77 153.44 149.33 158.63 158.72 158.86 158.02 163.56 164.77 22 154.31 155.09 154.93 154.93 153.36 149.14 158.84 158.86 159.19 158.21 163.67 164.81 23 154.81 155.05 154.95 155.02 153.25 148.99 158.80 160.40 159.21 160.06 163.88 166.02 24 155.28 154.93 155.12 154.95 153.20 148.88 158.68 159.66 159.01 163.24 164.03 165.12 25 155.02 154.82 155.17 154.97 153.09 148.73 158.54 159.54 158.80 162.73 163.97 164.54 26 27 28 29 30 31 MEAN 154.47 154.90 154.98 154.96 153.94 150.08 153.81 159.01 158.32 159.43 162.40 164.34 MAX 155.48 156.64 155.75 155.31 154.92 152.52 160.52 161.16 159.60 163.24 164.06 166.02 MIN 153.55 154.31 154.51 154.77 152.66 147.51 146.00 157.48 157.77 157.21 159.29 163.12 154.87 154.77 154.69 154.57 154.53 154.51 154.77 156.64 155.41 155.05 155.10 --- 155.75 155.14 155.19 155.23 155.11 155.10 154.92 154.89 154.88 155.16 154.93 154.94 152.95 152.80 152.66 ___ ___ ___ 148.53 148.33 148.13 147.95 147.73 147.51 158.40 158.30 157.99 160.52 159.46 ___ 160.14 159.23 159.15 159.12 157.80 157.95 158.59 158.40 158.54 158.67 158.48 --- 162.81 162.32 162.04 161.92 161.92 161.90 164.02 163.76 163.76 163.99 164.06 163.77 164.22 164.64 164.78 164.94 164.96 --- RIO DE LA PLATA BASIN 50045010 RIO DE LA PLATA BELOW LA PLATA DAM, PR 737 LOCATION.--Lat 18°20'45", long 66°14'17", Hydrologic Unit 21010005, 2.8 ml (4.5 km) west of Road 167, km 15.3, Buena Vista, Bayamon, 5.0 ml (8.0 km) east of Plaza de Corozal, 3.0 ml (4.8 km) northeast of Plaza de Naranjito. DRAINAGE ARBA.--173 ml a (448 fan'). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--July 1989 to current year. GAGE.—Water-stage recorder. Elevation of gage is 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. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL ADO SEP 1 .02 .43 2 .04 .46 3 .06 .72 4 .09 9.4 5 .10 43 6 139 30 7 661 15 8 191 17 9 69 11 10 23 2.7 11 10 .68 12 .63 .50 13 .21 3.3 14 .14 45 15 .12 106 16 .11 190 17 .11 107 18 .13 75 19 .14 91 20 .19 172 21 .27 361 22 .08 221 23 2.0 291 24 56 202 25 552 136 26 179 66 27 54 1320 28 11 2000 29 .71 608 30 .22 626 31 .34 - — TOTAL 1950.71 6751.19 MEAN 62.9 225 MAX 661 2000 MIN .02 .43 AC-FT 3870 13390 CFSM .36 1.30 IN. .42 1.45 350 207 170 153 146 106 52 26 16 8.6 4.6 3.2 3.1 3.9 128 135 80 63 49 37 25 28 36 90 193 755 667 487 491 293 186 4992.4 161 755 3.1 9900 .93 1.07 STATISTICS OF MONTHLY MEAN DATA MEAN 344 91.9 MAX 1107 225 (WY) 1991 1993 MIN .048 .16 (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 61.5 161 1993 .14 1990 FOR 149 150 142 125 105 125 232 365 166 115 75 60 54 50 40 29 21 15 10 7.3 5.8 14 112 105 97 76 51 26 606 389 189 3706.1 120 606 5.8 7350 .69 .80 201 146 104 80 36 18 6.3 3.3 3.1 3.1 3.4 3.7 4.3 3.4 3.4 3.6 3.7 3.7 3.6 3.7 3.7 3.6 3.5 3.6 3.5 3.5 3.6 3.5 ___ ___ --- 665.8 23.8 201 3.1 1320 .14 .14 FOR WATER YEARS 1989 442 1581 1992 .19 1990 64.2 222 1991 .27 1990 3.5 3.5 2.3 1.9 2.3 2.6 2.7 2.6 2.5 2.6 2.7 2.3 1.8 1.6 1.4 1.7 2.0 1.7 1.5 1.3 1.2 1.1 1.5 1.6 1.4 1.3 1.2 1.1 1.1 1.0 1.0 58.0 1.87 3.5 1.0 115 .01 .01 - 1993 34.0 83.2 1990 .10 1992 1992 CALENDAR YEAR 80405.26 220 27400 .00 .00 159500 1.27 17.31 222 .89 .00 Jan 6 Feb 26 Peb 26 1.0 1.0 .97 .94 .91 .91 .91 1.4 3.2 2.7 5.2 5.2 3.0 91 392 733 100 170 300 267 223 198 215 224 208 193 175 428 1080 1910 --- 6934.34 231 1910 .91 13750 1.34 1.49 758 1890 1400 279 98 989 1800 757 749 207 32 42 66 729 721 85 88 124 141 141 142 140 464 798 457 324 845 554 307 118 56 15301 494 1890 32 30350 2.86 3.29 61 63 65 68 74 74 66 63 70 74 78 75 68 65 79 113 77 82 1050 1990 404 278 330 232 194 167 158 131 125 219 6593 220 1990 61 13080 1.27 1.42 198 178 161 157 147 136 123 118 107 94 3680 996 481 462 313 281 259 237 201 203 192 115 299 430 662 474 452 268 203 143 137 11907 384 3680 94 23620 2.22 2.56 137 135 80 53 67 279 102 78 75 73 71 69 32 155 460 709 400 5.7 4.7 32 4.2 3.0 2.6 2.2 34 3.7 54 9.2 8.3 5.6 92 3236.2 104 709 2.2 6420 .60 .70 96 70 4.1 3.0 2.6 96 267 3.6 2.9 31 3.0 2.2 2.1 94 2.6 2.2 1.8 125 201 274 51 2.2 454 1340 451 263 67 2.3 2.1 56—— 3972.7 132 1340 1.8 7880 .77 .86 , BY WATER YEAR (WY) 68.9 231 1993 7.04 1992 FOR 1993 66068. 181 3680 . 16700 16. 131000 1. 14. 463 69 1. 245 494 1993 2.00 1991 WATER YEAR 44 Jul 11 02 Oct 1 13 Oct 14 Jul 11 43 Jul 11 05 22 2 77.5 220 1993 .16 1991 112 384 1993 .092 1992 WATER 136 182 37. 27400 . . 127000 34. 98700 . 10. 246 2. . 27.6 104 1993 .020 1989 YEARS 1989 8 Jan 00 Jul 00 Jul Jan 76 Jan 79 71 3 00 245 1047 1989 .001 1991 - 1993 1992 1990 6 1992 14 1989 14 1989 5 1992 5 1992 138 RIO DB LA PLATA BASIN 50045010 RIO DB LA PLATA AT BELOW LA PLATA DAM, PR—Continued WATER-QUALITY RECORDS PERIOD OP RECORDS.-- Water years 1990 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE! October 1989 to September 1993. INSTRUMENTATION.-- Automatic sediment sampler and DH-48. 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 LOADS: Maximum daily mean, 362,000tons (328,OOOtonnes) Jan. 06, 1992; Minimum daily 0.00 ton (0.00 tonne) several days. EXTREMES FOR WATER YEAR 1993.-- Water Year 1993 Suspended-sediment concentration (mg/L) maximum minimum Suspended-sediment discharge (tons per day) maximum minimum 382 (July 11) 1 (Several days) 10,700 (July 11) «.01 (Several days) SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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 31 139 661 191 69 23 10 2 56 552 179 54 11 .02 .04 .06 .09 .10 .63 .21 .14 .12 .11 .11 .13 .14 .19 .27 .08 .0 .71 .22 .34 2 2 2 2 2 6 6 6 5 4 2 1 1 1 1 1 1 1 1 1 1 1 1 5 15 10 6 4 3 3 2 .01 .01 .01 .01 .01 4.2 11 3.2 1.0 .27 .09 •e.Ol •e.Ol •e.Ol <.01 <.01 <.01 <.01 •e.Ol •e.Ol •e.Ol •e.01 .02 1.5 23 5.2 .98 .11 •e.01 •e.01 <.01 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) NOVEMBER .43 .46 .72 9.4 43 30 15 17 11 2.7 .68 .50 3.3 45 106 190 107 75 91 172 361 221 291 202 136 66 1320 2000 608 626 2 2 2 3 5 3 2 2 2 2 2 2 2 5 7 11 8 7 8 9 13 9 12 11 10 7 158 261 95 95 <. <. <. . • . . . . • <. < . . . 2. 5. 2. 1. 1. 5. 13 5. 9. 5. 3. 1. 1610 1770 177 162 01 01 01 10 56 27 09 09 06 01 01 01 02 71 8 6 5 5 9 3 5 3 9 5 3 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) DECEMBER 350 37 46 207 6 3.3 170 5 2.5 153 146 106 52 26 16 8.6 4.6 3.2 3.1 3.9 1.9 1.6 1.2 .63 .31 .18 .11 .05 .04 .04 .04 128 9 3.5 135 9 3.4 80 6 1.7 63 49 37 25 28 36 .71 .51 .39 .26 .28 .36 90 7 1.9 193 11 5.9 755 16 32 667 17 32 487 22 27 491 16 22 293 13 12 186 11 5.3 TOTAL 1950.71 50.57 6751.19 3779.01 4992.4 207.11 RIO DE LA PLATA BASIN 50045010 RIO DE LA PLATA BELOW LA PLATA DAM, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 739 MEAN MEAN CONCEN- 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 TOTAL 149 150 142 125 105 125 232 365 166 115 75 60 54 50 40 29 21 15 10 7.3 5.8 14 112 105 97 76 51 26 606 389 189 3706.1 10 8 8 8 8 9 11 12 9 8 7 7 6 6 6 6 6 6 6 6 6 6 8 7 6 6 6 6 21 5 4 4.0 3.1 3.3 2.8 2.8 3.0 7.9 12 4.9 2.6 1.6 1.1 .97 .82 .65 .46 .33 .24 .17 .13 .10 .22 2.5 2.2 1.5 1.3 .84 .44 38 5.7 2.1 107.77 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) FEBRUARY 201 146 104 80 36 18 6.3 3.3 3.1 3.1 3.4 3.7 4.3 3.4 3.4 3.6 3.7 3.7 3.6 3.7 3.7 3.6 3.5 3.6 3.5 3.5 3.6 3.5 ___ --- 665.8 4 4 4 3 3 3 3 3 3 3 3 3 3 5 5 5 5 7 9 11 13 14 13 ___ ___ —— 2.1 1.6 1.1 .77 .32 .16 .06 .03 .02 .02 .02 .03 .05 .04 .04 .04 .04 .04 .04 .05 .05 .05 .07 .09 .11 .13 .14 .13 ___ --- 7.34 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MARCH 3.5 3.5 2.3 1.9 2.3 2.6 2.7 2.6 2.5 2.6 2.7 2.3 1.8 1.6 1.4 1.7 2.0 1.7 1.5 1.3 1.2 1.1 1.5 1.6 1.4 1.3 1.2 1.1 1.1 1.0 1.0 58.0 11 9 7 5 4 3 2 2 1 1 1 1 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 .11 .08 .05 .03 .02 .02 .02 .02 .01 .00 .00 .01 .01 .00 .00 .01 .02 .01 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 .00 0.42 740 RIO DB LA PLATA BASIN 50045010 RIO DB LA PLATA BELOW LA PLATA DAM, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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) 1.0 1.0 .97 .94 .91 .91 .91 1.4 3.2 2.7 5.2 5.2 3.0 91 392 733 100 170 300 267 223 198 215 224 208 193 175 428 1080 1910 APRIL 2 2 2 2 2 2 2 2 2 2 2 2 2 7 43 92 8 10 12 12 12 12 12 12 12 11 11 50 120 233 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MAY .01 .01 .01 .01 .01 .01 .01 .01 .01 .01 .04 .04 .02 2.4 329 493 2.1 5.3 9.3 9.6 7.8 6.4 7.0 7.1 6.4 5.7 5.2 387 2320 2590 758 1890 1400 279 98 989 1800 757 749 207 32 42 66 729 721 85 88 124 141 141 142 140 464 798 457 324 845 554 307 118 56 101 260 196 35 23 115 233 109 114 31 6 5 6 88 53 6 4 4 5 5 5 5 11 18 14 12 18 15 13 9 6 590 1580 908 48 6.5 2150 2410 227 243 35 .49 .70 1.2 447 166 1.3 1.1 1.5 1.9 1.9 1.9 1.9 23 39 17 11 44 24 11 3.3 .82 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) JUNE 61 63 65 68 74 74 66 63 70 74 78 75 68 65 79 113 77 82 1050 1990 404 278 330 232 194 167 158 131 125 219 ___ 6 7 7 7 7 7 7 7 7 7 7 7 7 7 7 8 7 7 131 236 13 12 13 11 11 10 10 9 9 11 1.1 1.1 1.2 1.2 1.4 1.4 1.2 1.1 1.3 1.5 1.6 1.5 1.3 1.2 1.6 2.8 1.5 1.7 762 1490 16 9.1 12 7.0 5.7 4.6 4.2 3.2 3.3 6.6 TOTAL 6934.34 6193.43 15301 8997.51 6593 2349.4 141 RIO DB LA PLATA BASIN 50045010 RIO DB LA PLATA BELOW LA PLATA DAM, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CVS) (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 198 178 161 157 147 136 123 118 107 94 3680 996 481 462 313 281 259 237 201 203 192 115 299 430 662 474 452 268 203 143 137 11907 66068.44 JULY 11 10 10 10 10 9 9 9 8 8 382 141 82 83 12 8 5 3 3 3 3 3 9 13 28 14 14 11 10 6 3 ... MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AUGUST 5.8 5.0 4.4 4.2 3.8 3.4 3.0 2.8 2.4 2.0 10700 721 107 113 9.9 6.5 3.5 1.9 1.6 1.6 1.5 .90 11 17 50 18 17 8.8 7.4 2.5 1.1 11838.00 36061.88 137 135 80 53 67 279 102 78 75 73 71 69 32 155 460 709 400 5.7 4.7 32 4.2 3.0 2.6 2.2 34 3.7 54 9.2 8.3 5.6 92 3236.2 3 3 3 3 4 50 15 8 7 7 7 7 4 7 14 20 12 3 2 4 4 3 3 3 4 3 4 3 3 3 15 ... 1.1 1.1 .70 .42 .92 236 4.3 1.7 1.4 1.4 1.3 1.3 .49 5.6 19 52 20 .05 .03 1.3 .05 .03 .02 .02 1.5 .02 3.9 .07 .06 .04 96 451.82 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) SEPTEMBER 96 70 4.1 3.0 2.6 96 267 3.6 2.9 31 3.0 2.2 2.1 94 2.6 2.2 1.8 125 201 274 51 2.2 454 1340 451 263 67 2.3 2.1 56--- 3972.7 86 14 3 2 2 4 9 2 2 3 2 2 2 15 4 3 2 6 10 11 6 2 56 175 76 45 13 3 2 4 --- ... 55 38 .04 .02 .02 3.9 13 .02 .02 1.5 .02 .02 .02 70 .03 .02 .00 4.7 5.6 11 1.4 .02 480 1260 96 32 4.1 .03 .02 3.0 --- 2079.50 142 RIO DB LA PLATA BASIN 50046000 RIO DB LA PLATA AT HIGHWAY 2 NEAR TOA ALTA, PR 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 AREA.--208 mi* (539 km1 ), 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 and crest-stage gage. Datum of gage is 9.15 ft (2.789 m), above mean sea level. Prior to October, 1984, at site about 1.0 mi (1.6 km) upstream at mean sea level datum. 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 ftVs (3,400 mVs), 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. DAY OCT DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES NOV DEC JAN FEE MAR APR MAY JUN JUL AUG SEP 1 16 20 2 17 23 3 23 42 4 17 810 5 15 132 6 13 71 7 578 44 8 191 35 9 91 38 10 55 31 11 49 23 12 24 21 13 17 114 14 15 108 15 12 50 16 14 150 17 43 98 18 33 90 19 18 68 20 14 65 21 13 366 22 18 171 23 45 286 24 44 208 25 403 122 26 215 64 27 76 873 28 35 2810 29 21 897 30 20 629 31 18 TOTAL 2163 8459 MEAN 69.8 282 MAX 578 2810 MIN 12 20 AC-FT 4290 16780 CFSM .35 1.41 IN. .40 1.57 STATISTICS OF MONTHLY MEAN MEAN 502 455 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 RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 446 229 157 137 108 90 71 48 39 34 30 27 27 41 251 118 96 103 62 53 43 72 66 162 328 2000 1470 632 723 517 244 8424 272 2000 27 16710 1.36 1.57 DATA 344 1352 1971 23.4 1992 FOR 176 145 144 128 106 118 191 392 198 118 90 79 77 74 67 63 57 55 57 57 67 e86 e!20 e70 e62 e80 e75 50 394 454 168 4018 130 454 50 7970 .65 .75 134 99 67 57 48 37 31 29 27 26 26 29 27 26 26 25 29 25 25 27 33 26 24 27 27 26 25 24 ___ ___ --- 1032 36.9 134 24 2050 .18 .19 FOR WATER YEARS 1960 193 929 1992 16.9 1984 134 409 1989 16.0 1983 23 25 25 23 26 24 24 22 23 21 27 23 19 19 18 35 38 27 20 19 19 19 23 31 30 20 18 18 19 30 18 726 23.4 38 18 1440 .12 .14 - 1993 106 468 1969 8.31 1986 1992 CALENDAR YEAR 72222 197 15900 7 9 143300 13 275 31 12 .2 Jan 6 .9 Mar 25 .9 Mar 20 .99 .45 16 17 15 15 16 15 17 20 52 73 341 250 81 137 106 1080 91 62 75 297 217 106 61 59 58 51 49 454 1020 3830 --- 8681 289 3830 15 17220 1.45 1.62 341 2040 1600 463 94 624 3680 982 720 389 117 85 79 418 854 134 82 81 85 87 94 130 342 817 463 441 1170 613 312 184 189 17710 571 3680 79 35130 2.86 3.30 e!20 e90 e79 71 66 65 66 83 121 86 69 64 63 61 57 82 59 59 673 2060 489 203 278 179 154 123 105 93 76 139 5933 198 2060 57 11770 .99 1.10 136 130 135 116 94 88 139 92 75 64 3000 2090 532 393 255 221 196 183 162 141 149 181 292 666 1210 800 657 409 225 141 129 13101 423 3000 64 25990 2.12 2.44 128 115 100 69 68 258 103 82 79 81 75 73 68 58 358 553 512 81 51 65 56 46 40 34 72 54 101 67 48 48 135 3678 119 553 34 7300 .59 .68 132 120 51 39 37 34 281 46 35 127 65 40 58 109 60 229 54 153 198 270 111 50 47 1180 359 202 113 55 38 60 4353 145 1180 34 8630 .73 .81 , BY WATER YEAR (WY) 200 722 1987 5.07 1984 FOR 1993 78278 214 3830 12 16 13900 16 155300 1 14 498 75 21 375 1939 1985 7.63 1984 WATER YEAR Apr 30 Oct 15 Apr 1 Jul 11 .01 Jul 11 .07 .57 173 847 1970 11.4 1977 155 690 1961 13.9 1976 WATER 266 824 36 40000 2 2 118000 26 2 193000 1 18 509 94 19 262 1677 1979 16.5 1976 YEARS 1960 - .3 Oct 9 .7 Apr 17 .9 Apr 15 Jan 5 .39 Jan 5 .2 Apr 25 .33 .12 323 1691 1960 19.2 1991 1993 1971 1977 1970 1984 1984 1992 1992 1984 e Estimated RIO DB LA PLATA BASIN 50046000 RIO DB LA PLATA AT HWY 2 NR TOA ALTA, PR (National stream-quality accounting network station) WATER-QUALITY RECORDS LOCATION.--Lat 18°24'41", long 66°15'39", at 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 AREA.—208 mi' (539 km'), exclude 8.2 mi' (21.2 km1 ) upstream from Lago Carite, flow from which is diverted to Rio Guamani. PERIOD OF RECORD.—Hater years 1958 to current year WATER-QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 05... DEC 24... FBB 1993 01. .. APR 05... JUN 09... SEP 07... DATE OCT 1992 05... DEC 24... FBB 1993 01... APR 05... JUN 09... SEP 07. .. DATE OCT 1992 05... DEC 24. .. FBB 1993 01... APR 05... JUN 09... SEP 07. .. TIME 1115 0805 0835 0915 0915 0900 HARD- NESS NONCARB HH HAT TOT FLD HO/L AS CACO3 130 210 160 130 160 120 SOLIDS, RESIDUE AT 180 DBO. C DIS- SOLVED (MG/L) 289 250 193 292 259 228 DIS- CHARGE, INST. CUBIC FEET PER SECOND 16 58 139 17 70 500 CALCIUM DIS- SOLVED (MG/L AS CA) 59 49 36 56 57 40 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 291 228 203 284 249 218 SPE- CIFIC CON- DUCT- ANCE (US/CM) 472 405 342 461 428 340 MAGNE- SIUM, DIS- SOLVED (HG/L AS HO) 11 8.8 11 13 11 12 SOLIDS, DIS- SOLVED (TONS PER DAY) 12.2 35.7 76.2 13.0 47.1 294 PH HATER WHOLE FIELD (STAND- ARD UNITS) 7.4 7.0 7.6 7.2 7.1 8.1 SODIUM, DIS- SOLVED (MG/L AS NA) 23 18 17 23 20 19 NITRO- GEN, NO2+NO3 DIS- SOLVED (MG/L AS N) 0.770 -- 0.360 0.390 -- 0.160 TEMPER- ATURE HATER (DBG C) 30.0 25.0 25.0 27.0 27.5 29.2 SODIUM AD- SORP- TION RATIO 0.7 0.6 0.6 0.7 0.6 0.7 NITRO- GEN, AMMONIA DIS- SOLVED (MG/L AS N) 0.030 -_ 0.070 0.040 -- 0.080 TUR- BID- ITY (NTU) 0.30 13 0.50 20 8.0 5.2 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 3.3 2.8 2.6 3.2 3.0 6.8 NITRO- GEN, AMMONIA DIS- SOLVED (MG/L AS NH4) 0.04 -_ 0.09 0.05 -- 0.10 OXYGEN, DIS- SOLVED (HG/L) 6.9 4.0 5.0 5.2 3.4 3.9 ALKA- LINITY HAT HH TOT FET FIELD MG/L AS CAC03 200 160 130 180 160 140 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (HG/L AS N) 0.40 __ 0.40 0.30 -- 0.50 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 90 84 69 124 72 57 SULFATE DIS- SOLVED (MG/L AS S04) 19 17 15 22 20 22 PHOS- PHORUS TOTAL (MG/L AS P) 0.190 -_ 0.140 0.110 -- 0.070 COLI- FORM, FECAL, 0.7 UM-HF (COLS./ 100 ML) K900 K1800 K760 240 K19000 5200 CHLO- RIDE, DIS- SOLVED (MG/L AS CL) 33 23 20 36 26 19 PHOS- PHORUS DIS- SOLVED (MG/L AS P) 0.180 _- 0.100 0.090 -- 0.070 STREP- TOCOCCI FECAL, KF AGAR (COLS. PER 100 ML) 500 K1800 700 64 K2100 1000 FLUO- RIDE, DIS- SOLVED (MG/L AS F) 0.20 0.10 0.10 0.10 0.10 0.10 PHOS- PHORUS ORTHO, DIS- SOLVED (MG/L AS P) 0.160 __ 0.100 0.110 __ 0.050 HARD- NESS TOTAL (MG/L AS CAC03) 190 160 140 190 190 150 SILICA, DIS- SOLVED (MG/L AS SI02) 18 15 19 18 17 19 PHOS- PHATE, ORTHO, DIS- SOLVED (MG/L AS PO4) 0.49 _- 0.31 0.34 __ 0.15 K «= non- ideal count 144 RIO DE LA PLATA BASIN 50046000 RIO DE LA PLATA AT HWY 2 NR TOA ALT A, PR—Continued (National stream-quality accounting network station) DATE OCT 1992 05... DEC 24. .. FEB 1993 01... APR 05... JUN 09... SEP 07... ALUM- INUM, DIS- SOLVED (UG/L AS AL) ARSENIC DIS- SOLVED (UG/L AS AS) BARIUM, DIS- SOLVED (UG/L AS BA) BERYL- LIUM, DIS- SOLVED (UG/L AS BE) CADMIUM DIS- SOLVED (UG/L AS CD) CHRO- MIUM, DIS- SOLVED (UG/L AS CR) COBALT, DIS- SOLVED (UG/L AS CO) COPPER, DIS- SOLVED (UG/L AS CO) IRON, DIS- SOLVED (UG/L AS FE) LEAD, DIS- SOLVED (UG/L AS PB) LITHIUM DIS- SOLVED (UG/L AS LI) 10 80 DATE OCT 1992 05. .. DEC 24... FEB 1993 01. .. APR 05... JUN 09. .. SEP 07... 62 34 78 25 50 <0.5 35 <0.5 <3 <3 0.2 270 150 220 150 14 30 90 MANGA- NESE, DIS- SOLVED (UG/L AS MN) 2 1 MERCURY DIS- SOLVED (UG/L AS HG) 57 45 MOLYB- DENUM, DIS- SOLVED (UG/L AS MO) <0.5 <0.5 NICKEL, DIS- SOLVED (UG/L AS NI) 1 * SELE- NIUM, DIS- SOLVED (UG/L AS SB) <1 * SILVER, DIS- SOLVED (UG/L AS AG) <3 <3 STRON- TIUM, DIS- SOLVED (UG/L AS SR) 2 3 VANA- DIUM, DIS- SOLVED (UG/L AS V) 33 11 ZINC, DIS- SOLVED (UG/L AS ZN) <4 <4 <4 <4 12 15 <6 7 5 9 7 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 1992 TO SEPTEMBER 1993 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT 145 DATE OCT 1992 05... DEC 1993 24... FBB 01... APR 05.. . JUN 09... SEP 07... TIME 1115 0805 0835 0915 0915 0900 STREAM- FLOW, INSTAN- TANEOUS (CFS) 16 58 139 17 70 168 SEDI- MENT, SUS- PENDED (MG/L) 16 18 20 44 31 48 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 0.67 2.77 7.43 2.0 5.76 22 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 95 96 75 65 95 75 PESTICIDE ANALYSES JUN 29 DATE 1993 TIME 0930 PCB, TOTAL (UG/L) <0.1 ALDRIN, TOTAL (UG/L) <0.010 CHLOR- DANE, TOTAL (UG/L) <0.1 DDD, TOTAL (UG/L) <0.010 DDE, TOTAL (UG/L) <0.010 DOT, TOTAL (UG/L) <0.010 DI- AZINON, TOTAL (UG/L) <0.01 DI- BLDRIN TOTAL (UG/L) <0.010 BNDO- SULFAN, TOTAL (UG/L) <0.010 DATE JUN 1993 29.. . ENDRIN WATER UNFLTRD RBC (UG/L) <0.010 BTHION, TOTAL (UG/L) <0.01 HBPTA- CHLOR, TOTAL (UG/L) <0.010 HEPTA- CHLOR BPOXIDB TOTAL (UG/L) <0.010 LINDANB TOTAL (UG/L) <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 JUN 1993 29... PARA- THION, TOTAL (UG/L) <0.01 NAPH- THA- LENES, POLY- CHLOR. TOTAL (UG/L) <0.10 PBR- THANB TOTAL (UG/L) <0.1 TOX- APHENE, TOTAL (UG/L) <1 TOTAL TRI- THION (UG/L) <0.01 2,4-D, TOTAL (UG/L) <0.01 2,4,5-T TOTAL (UG/L) <0.01 2, 4 -DP TOTAL (UG/L) <0.01 SILVEX, TOTAL (UG/L) <0.01 146 THIS PAGE WAS LEFT BLANK INTENTIONALLY 747 ^ f>? fv "--v, -'.' *f f"^- -— ^ ^ v \- — <-/ ( «•»* ,, , ^r .^047530 \ JL • 218 J/lU <-ATA*^» Dy"1"*^ ./^4 « •&• ^MiM l »%~/ ^ T o: f»o^}^ L> o y n <? fit r iffSfc iftn^T&rrnjfS ££?€> 1 ^r .3% *"• «*' *•*•. ' %^ al^ ' C^^ W •21^. ' ^,~~~-*'"~"™"~^"^"r V 048510, - "' L.Tfni!?s*or!^ ^^ —— •'"• ^--Jj-'^\ SAYAMOH.%^^ <k. v-^ Syn*t)us orsd ; ,; vvs _/ V \. | -. ''i/ Mdtm«'-( ! ery rotc.s \/ , •*• —— ' \ ^ ^ S \ !' 'S H^SV' '' ^ ' ) i _yi2-S/ ( ,:' ^ ^ fa^0 < l /' ' J 1 j \ n'^' — '- i-J -x (' - - J ' \ • r-;? /A /w ^ v i, \5 / ;^n; \ i V* _ ^.^ •- f~ ( \( ' > ^ ^\ 047850 J^r v- ../^X s vx / ^ ,--' C* V^'lK K s i. \ Urmnog* Oojr( dUi"yx j~---- "*"* r"! 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' '}// i ~~"--^ AGUAS «Ur N43 « ; ,«r<i« J» ;, -^la ?-(t,r .,_, l> —— EXPLANATION SURFACE-WATER STATION AND NUMBER QUALITY-OF-WATER STATION AND NUMBER WELL AND WELL NUMBER LAKE-ELEVATION STATION O METERS tn t~ >"• Figure 19.-Ftto Hondo to Rto Puerto Nuevo basins. RIO HONDO BASIN 50047530 RIO HONDO AT FLOOD CHANNEL NEAR CATANO, PR WATER-QUALITY RECORDS LOCATION.—Lat 18°26'13", long 66°09'36", at Rio Hondo Channel, 800 ft (245 m) 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 AREA.—Indeterminate. PERIOD OF RECORD.—Water years 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE NOV 1992 05... JAN 1993 05... MAR 08... MAY 04... JUN 21... AUG 24... TIME 1050 1115 0830 0815 0920 0900 DIS- CHARGE, SPB- INST. CIFIC CUBIC CON- FEET DUCT- PER ANCE SECOND (US/CM) 940 16000 25000 3500 7600 39000 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.3 8.1 8.2 6.9 7.1 7.8 TEMPER- ATURE WATER (DEG C) 28.0 26.0 24.5 28.5 27.5 31.5 TUR- BID- ITY (NTU) 24 9.0 2.0 31 0.80 20 OXYGEN, DIS- SOLVED (MG/L) 4.3 11.6 7.0 3.1 4.0 4.7 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 54 140 82 39 50 62 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 58 72 370 46 120 670 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K140000 2100 20000 41000 15000 25000 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 22000 K450 20000 32000 19000 6900 DATE NOV 1992 05... JAN 1993 05. .. MAR 08. .. MAY 04. .. JUN 21. .. AUG 24... 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, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS NA) 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) 700 26 66 129 1099 17 41 430 29 51 74 580 12 23 3800 18 270 770 6500 46 180 CAC03 110 140 160 89 130 160 AS S) AS S04) AS CL) <0.5 290 2100 <0.5 170 990 1700 11000 SOLIDS, RESIDUE DATE NOV 1992 05... JAN 1993 05.. . MAR 08... MAY 04.. . JUN 21... AUG 24... FLUO- RIDE, DIS- SOLVED (MG/L AS F) 0.20 -- — 0.20 -- 2.1 SILICA, DIS- SOLVED (MG/L AS SI02) 10 -- — 8.4 — 3.7 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 3800 -- -_ 1950 -- 20500 SOLIDS, TOTAL DIS- AT 105 SOLVED DBG. C, (TONS SUS- PBR FENDED DAY) (MG/L) 24 18 4 41 16 87 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.090 0.080 0.060 0.060 0.150 0.350 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.010 0.020 0.040 0.040 0.050 0.050 NITRO- GEN, N02+N03 TOTAL (MG/L AS N) 0.100 0.100 0.100 0.100 0.200 0.400 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 4.40 8.90 6.60 2.80 4.20 0.70 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 2.6 6.1 5.4 3.6 4.9 3.4 non-ideal count RIO HONDO BASIN 50047530 RIO HONDO AT FLOOD CHANNEL NEAR CATANO, PR—Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 149 DATE NOV 1992 05... JAN 1993 05... MAR 08... MAY 04.. . JUN 21... AUG 24... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 7.0 15 12 6.4 9.1 4.1 NITRO- GEN, TOTAL (HG/L AS N) 3.0 2.2 2.4 4.2 9.3 1.8 NITRO- GEN, TOTAL (MG/L AS NO3) 13 9.7 11 8.4 4.1 8.0 PHOS- PHORUS TOTAL (MG/L AS P) 0.280 0.260 0.040 0.430 0.210 0.290 ARSENIC TOTAL (UG/L AS AS) 9 -- -- 3 -- -- BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 -- — <100 -- -- BORON, TOTAL RECOV- ERABLE (UG/L AS B) 500 -- -- 260 -- -- CHRO- CADMIUM HIUM, COPPER, TOTAL TOTAL TOTAL RECOV- RBCOV- RECOV- ERABLE BRABLB BRABLB (UG/L (UG/L (UG/L AS CD) AS CR) AS CU) <1 <1 <10 — — <1 <1 <10 __ ._ DATE NOV 1992 05. . . JAN 1993 05... MAR 08.. . MAY 04... JUN 21.. . AUG 24... 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 (HG/L AS CN) PHENOLS TOTAL (UG/L) MBTHY- LBNB BLUE ACTIVE SUB- STANCE (HG/L) 780 940 380 190 0.10 0.10 20 40 <0.010 <0.010 0.34 0.26 750 RIO DB BAYAMON BASIN 50047535 RIO DB BAYAMOft AT ARENAS, PR LOCATION.—Lat 18«10'11", long 66°07'18", Hydrologic Unit 21010005, at left bank, 2.61 mi (4.20 km) southeast of plaza de Cidra, 0.56 mi (0.90 km) southwest from Bscuela Segunda Unidad de Bayamdn, and 2.70 mi (4.34 km) northeast from Central Cayey. DRAINAGE AREA.--0.45 mi> (1.16 km>). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--July 1992 to current year. GAGE.—Water-stage recorder. Elevation of gage is 1,378 ft (420 m), from topographic map. REMARKS.--Records poor. 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 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. STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1992 - 1992, BY WATER YEAR (WY) MEAN MAX (WY) MIN (WY) AUG .46 .46 1992 .46 1992 SBP 18 09 07 06 06 06 06 __ -- -- -- — — -- .06 .10 .09 .07 6.2 2.9 .75 .36 .21 .14 .28 .18 .17 .24 .23 .13 .11 .10 .11 .10 .08 .06 .06 .06 .06 .21 .13 .82 .14 .07 .13 14.35 .46 6.2 .06 28 1.03 1.19 .07 .06 .11 .08 .08 .13 .09 .10 .95 .12 .08 .06 .05 .05 .05 .77 2.3 1.0 12 17 5.0 2.4 1.5 .93 .60 .39 .18 .12 .11 .10 46.48 1.55 17 .05 92 3.44 3.84 1.55 1.55 1992 1.55 1992 RIO DE BAYAMON BASIN 50047535 RIO DE BAYAMON AT ARENAS, PR-Continued DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES 151 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUQ SEP 1 .10 .19 2 .09 .18 3 .08 .27 4 .07 .81 5 .09 .35 6 3.2 .69 7 1.5 .55 8 .55 .32 9 .16 .37 10 .15 2.4 11 .12 . 19 12 .09 .11 13 .10 .11 14 .10 . 12 15 .11 .11 16 .11 . 12 17 .15 1.0 18 .22 1.1 19 .16 .80 20 .13 .23 21 .12 .10 22 .11 .61 23 .10 .41 24 .71 .12 25 .34 .11 26 .09 .11 27 .10 9.9 28 .11 7.4 29 .11 4.2 30 .13 6.1 31 .19 - — TOTAL 9.39 39.08 MEAN .30 1.30 MAX 3.2 9.9 MIN .07 .10 AC-FT 19 78 CFSM .67 2.89 IN. .78 3.23 1.9 1.1 1.8 1.0 .56 .30 .21 .15 .13 .11 .10 .10 .12 .30 .16 .14 .16 .17 .16 .15 .14 .20 .15 .21 .20 e5.6 el.O e.81 .53 .37 1.5 19.53 .63 5.6 .10 39 1.40 1.61 STATISTICS OP MONTHLY MEAN DATA MEAN .30 1.30 MAX .30 1.30 (WY) 1993 1993 MIN .30 1.30 (WY) 1993 1993 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 (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS .63 .63 1993 .63 1993 1.1 .84 .72 .59 .50 1.3 1.5 1.1 1.3 .83 .39 .31 .26 .75 .31 .26 .22 .18 .18 .13 .11 .95 .65 .32 .69 .35 .25 .38 2.0 .53 .24 19.24 .62 2.0 .11 38 1.38 1.59 FOR WATER .62 .62 1993 .62 1993 .16 .12 .14 .13 .16 .19 .18 .20 .12 .11 .16 .31 .44 .18 .15 .19 .12 .12 .12 .11 .17 .12 .10 .10 .10 .11 .12 .12 ___ ___ --- 4.35 .16 .44 .10 8.6 .35 .36 YEARS 1992 - .16 .16 1993 .16 1993 FOR 1993 309. . 28 . 255 5. 614 1. 25. 1. . .12 .12 .11 .11 .12 .12 .13 .12 .12 .11 .09 .08 .07 .08 .09 .08 .17 .14 .16 .11 .09 .08 .08 .09 .08 .07 .07 .06 .05 .05 .05 3.02 .097 .17 .05 6.0 .22 .25 .05 .05 .05 .05 .04 .04 .04 .26 .27 .13 .10 .17 .51 e3.2 e2.3 el. 5 .50 .20 .13 .13 .17 .11 .07 .06 .07 .10 .07 .20 2.3 .71 —— 13.58 .45 3.2 .04 27 1.01 1.12 1993, BY WATER .097 .097 1993 .097 1993 .45 .45 1993 .45 1993 10 17 3.2 1.1 .73 .71 .52 .40 .66 .74 .45 .35 .29 17 2.2 1.1 .71 .44 .32 .30 .29 .27 .30 .28 .31 1.0 .53 .42 .32 .29 .25 62.48 2.02 17 .25 124 4.48 5.17 YEAR (WY) 2.02 2.02 1993 2.02 1993 .24 .24 .22 .21 .20 .18 .17 .16 .16 .14 .13 .12 .14 .14 .21 .15 .10 .13 8.2 5.0 .91 8.9 1.9 .67 .34 .22 .16 .13 .14 .21 --- 29.82 .99 8.9 .10 59 2.21 2.47 .99 .99 1993 .99 1993 WATER YEAR 56 85 04 05 40 88 59 4 19 09 Jul 11 Apr 5 Apr 1 May 14 May 14 .15 .18 .20 .16 .13 .13 .16 .17 .13 .12 28 3.5 1.1 .56 .27 .33 .15 .10 .09 .09 .09 4.0 6.9 13 2.7 1.3 .86 .46 .33 .26 .24 65.86 2.12 28 .09 131 4.72 5.44 2.12 2.12 1993 2.12 1993 WATER 28 255 5 614 1 25 1 .22 .23 .21 .19 .22 .20 .19 .19 .19 .23 .24 .20 .19 .19 .29 14 1.9 .72 .39 .28 .24 .45 .67 .25 .19 .16 .15 .15 .15 .15 .16 23.19 .75 14 .15 46 1.66 1.92 .61 .75 1993 .46 1992 YEARS 1992 .85 .85 .85 Jul .04 Apr .05 Apr May .40 May .88 .61 .5 .18 .08 .15 .16 .17 .15 .16 .27 .14 .19 .14 e.25 .13 .12 .11 .12 .12 .13 .18 .30 .13 .25 .13 .11 e!3 1.5 .39 .24 .18 .18 .62 .30 20.02 .67 13 .11 40 1.48 1.65 1.11 1.55 1992 .67 1993 - 1993 1993 1993 11 1993 5 1993 1 1993 14 1993 14 1993 e Estimated RIO DE BAYAMON BASIN 50047540 RIO SABANA AT VISTA MONTE, PR LOCATION.--Lat 18°10'28", long 66°08'38", Hydrologic Unit 21010005, at left bank, 1.2 mi (1.9 km) southeast of Plaza de Cidra, 1.2 mi (1.9 km) southwest from Escuela Segunda Unidad de Bayamon, and 0.4 mi (0.6 km) upstream from Lago de Cidra. DRAINAGE AREA.--0.80 mi 1 (2.07 km1 ). HATER-DISCHARGE RECORDS PERIOD OF RECORD.—August 1992 to current year. GAGE.--Hater-stage recorder and crest-stage gage. Elevation of gage is 1,345 ft (410 m), from topographic map. REMARKS.--Records 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 JDL 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 TOTAL —- 36.98 MEAN —— 1.23 MAX —— 12 MIN —— .32 AC-FT —— 73 CFSM —- 1.54 IN. —— 1.72 STATISTICS OF MONTHLY MEAN DATA FOR HATER YEARS 1992 - 1992, BY HATER YEAR (HY) MEAN —— 1.23 MAX —— 1.23 (WY) —— 1992 MIN —— 1.23 (WY) -- 1992 e Estimated e.39 14 3.0 .78 .64 .64 .60 .70 .58 .61 .68 .86 .54 .48 .45 .42 .40 .38 .37 .37 .35 .35 .39 .34 .69 .46 .35 .39 .40 .39 .40 .34 .58 .94 .44 .57 .66 .34 .33 .32 .32 .33 .37 .64 1.5 .55 6.5 12 4.1 1.7 .72 .37 .35 .33 .35 .36 .40 .38 ___ RIO DE BAYAMON BASIN 50047540 RIO SABANA AT VISTA MONTE, PR--Continued DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES 153 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 .41 .60 2 .42 .40 3 .44 .88 4 .47 .80 5 7.7 .47 6 1.2 .52 7 .51 .48 8 .47 .45 9 .50 .47 10 .50 3.2 11 .50 .54 12 .69 .51 13 .37 .54 14 .42 .55 15 .44 .55 16 .78 .57 17 .60 1.7 18 1.6 .90 19 2.0 1.1 20 .48 .71 21 .52 .54 22 .59 .73 23 .67 .61 24 .77 .58 25 .54 .58 26 .47 .60 27 .50 17 28 .50 4.5 29 .49 1.7 30 .46 3.9 31 .60 TOTAL 26.61 46.68 MEAN .86 1.56 MAX 7.7 17 MIN .37 .40 AC-FT 53 93 CFSM 1.07 1.94 IN. 1.24 2.17 STATISTICS OF MONTHLY MEAN MEAN .86 1.56 MAX .86 1.56 (WY) 1993 1993 MIN .86 1.56 (WY) 1993 1993 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 1.2 .97 1.2 .85 .75 .71 .65 .68 .76 .71 .70 .81 .98 1.3 .83 .73 .79 .80 .77 .74 .68 .86 .72 .88 .87 9.2 .71 .72 .80 .90 1.1 34.37 1.11 9.2 .65 68 1.39 1.60 DATA 1.11 1.11 1993 1.11 1993 .84 .78 .78 .76 .79 1.1 1.6 .91 .82 .70 .64 .63 .56 .67 .47 .45 .42 .40 .40 .41 .40 1.6 .61 .42 .49 .50 .46 .48 2.3 .54 .44 22.37 .72 2.3 .40 44 .90 1.04 FOR WATER .72 .72 1993 .72 1993 .42 .41 .44 .43 .42 .40 .36 .32 .34 .32 .31 .39 .33 .29 .29 .27 .29 .29 .27 .36 .29 .29 .29 .28 .27 .27 .26 .22 ___ ___ --- 9.12 .33 .44 .22 18 .41 .42 YEARS 1992 - .33 .33 1993 .33 1993 FOR 1993 429. 1. 49 296 4. 852 1. 19. 1. ^ . .23 .21 .19 .19 .18 .17 .17 .16 .15 .15 .14 .14 .13 .13 .12 .13 .16 .13 .14 .13 .12 .13 .14 .13 .11 .12 .12 .12 .12 .13 .13 4.52 .15 .23 .11 9.0 .18 .21 1993 .15 .15 1993 .15 1993 .14 .15 .15 .13 .14 .14 .15 1.1 1.1 .24 .94 .20 1.7 5.6 2.1 .67 .40 .32 .38 .57 1.8 .34 .35 .34 .37 .33 .43 1.5 14 1.1 --- 36.88 1.23 14 .13 73 1.54 1.71 , BY WATER 1.23 1.23 1993 1.23 1993 16 23 3.8 .58 .34 1.9 .29 .28 .79 .53 .36 .29 .23 18 .77 .32 .23 .19 .17 .15 .14 .14 .17 .14 .20 .39 .18 .15 .14 .13 .12 70.12 2.26 23 .12 139 2.83 3.26 YEAR (WY) 2.26 2.26 1993 2.26 1993 e.12 e.12 e.12 e.12 e.12 e.12 e.12 e.12 e.12 .12 .12 .11 .12 .12 .15 .12 .11 .16 7.1 6.2 .38 8.3 .71 .30 .21 .18 .16 .14 .16 .16 --- 26.21 .87 8.3 .11 52 1.09 1.22 .87 .87 1993 .87 1993 WATER YEAR 51 18 11 12 63 11 47 97 2 42 13 Jul 11 Mar 25 Jun 6 Sep 23 Sep 23 Mar 23 .13 .14 .14 .14 .13 .15 .11 .13 .12 .12 49 5.3 1.2 .80 .68 .65 .58 .58 .59 .59 .58 2.8 2.7 20 2.2 1.0 .77 e.61 e.56 e.52 e.49 93.51 3.02 49 .11 185 3.77 4.35 3.02 3.02 1993 3.02 1993 WATER 1 1 1 49 296 4 852 1 19 1 e.47 e.46 e.44 e.43 e.54 .57 .55 .50 .51 .41 .44 .41 .42 .40 .44 16 .97 .48 .41 .36 .33 .46 .51 .28 .28 .27 .50 .25 .27 .28 .30 28.94 .93 16 .25 57 1.17 1.35 .93 .93 1993 .93 1993 YEARS 1992 .18 .18 .18 Jul .11 Mar . 12 Jun Sep . 63 Sep .11 Mar .47 .99 .4 .42 .14 .29 .31 .26 .23 .28 .75 .21 .22 .22 .37 .20 .18 .17 .18 .18 .19 .28 .46 .20 .38 .19 .17 22 1.2 .25 .18 .16 .15 .17 .15 30.18 1.01 22 .15 60 1.26 1.40 1.12 1.23 1992 1.01 1993 - 1993 1993 1993 11 1993 25 1993 6 1993 23 1993 23 1993 23 1993 e Estimated 154 RIO DE BAYAMON BASIN 50047550 LAGO CIDRA AT DAMSITB NEAR CIDRA, PR LOCATION.—Lat 18°11'57", long 66 0 08'29", Hydrologic Unit 21010005, at Lago de Cidra Dam on Rio de BayamSn, 1.9 mi (3.0 km) northeast of Plaza de Cidra and 1.8 mi (2.9 km) northwest of Escuela Segunda Unidad de Bayam6n. DRAINAGE AREA.--8.26 mi» (21.39km'). 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 hm3 ) 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 1,324.14 ft (403.60 m), July 11, 1993; minimum elevation 1,305.18 ft (397.82 m), Sept. 30, 1990. EXTREMES OBSERVED FOR CURRENT YEAR.--Maximum elevation, 1,324.14 ft (403.60 m), July 11; minimum elevation, 1,311.77 ft (399.83 m), Apr. 8. 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 1,328 Contents, in acre-feet 4,400 5,200 6,920 DAY ELEVATION (FEET NGVD), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY OBSERVATION AT 24:00 VALUES 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 1313.89 1313.85 1313.80 1313.78 1313.83 1314.23 1314.60 1314.65 1314.69 1314.67 1314.58 1314.54 1314.60 1314.62 1314.58 1314.49 1314.50 1314.58 1314.64 1314.86 1314.94 1314.96 1315.01 1315.07 1315.16 1315.19 1315.17 1315.10 1315.02 1314.92 1314.85 1314.62 1315.19 1313.78 1314.79 1314.68 1314.73 1314.85 1314.96 1315.04 1315.05 1315.06 1315.04 1315.32 1315.24 1315.14 1314.99 1314.91 1314.86 1314.82 1314.99 1315.24 1315.38 1315.44 1315.45 1315.42 1315.33 1315.30 1315.35 1315.34 1316.20 1316.83 1317.01 1317.43 1315.34 1317.43 1314.68 1317.61 1317.73 1317.78 1317.84 1317.89 1317.95 1317.86 1317.84 1317.82 1317.82 1317.82 1317.77 1317.64 1317.74 1317.77 1317.74 1317.69 1317.63 1317.57 1317.51 1317.40 1317.29 1317.10 1316.90 1316.71 1317.78 1317.83 1317.82 1317.83 1317.81 1317.83 1317.66 1317.95 1316.71 1317.82 1317.81 1317.79 1317.76 1317.77 1317.78 1317.93 1317.92 1317.92 1317.89 1317.87 1317.85 1317.82 1317.83 1317.78 1317.74 1317.70 1317.65 1317.61 1317.55 1317.51 1317.67 1317.66 1317.63 1317.61 1317.57 1317.53 1317.51 1317.61 1317.57 1317.53 1317.72 1317.93 1317.51 1317.49 1317.53 1317.63 1317.69 1317.72 1317.73 1317.73 1317.73 A A A A A A A A A 1317.64 1317.51 1317.44 1317.27 1317.09 1316.91 1316.65 1316.46 1316.39 1316.31 1316.29 ___ --- ___ 1316.27 1316.34 1316.30 1316.28 1316.26 1316.24 1316.07 1316.94 A A A A A 1315.00 1314.88 1314.87 1314.90 1314.88 1314.79 1314.60 1314.45 1314.36 1314.25 1314.09 1313.88 1313.72 1313.62 1313.50 1313.36 1313.19 1313.05 ___ ___ 1312.99 1312.75 1312.54 1312.31 13 12 . 12 1311.98 1311.87 1311.96 1311.90 1311.85 1312.02 1312.12 1312.52 1313.06 1314.06 1314.20 1314.28 1314.33 1314.32 1314.36 1314.60 1314.62 1314.62 1314.61 1314.60 1314.62 1314.55 1314.58 1315.46 1315.60 --- 1313.51 1315.60 1311.85 1316.80 1316.74 1318.09 1318.18 1318.25 1318.61 1318.74 1318.81 1319.02 1319.17 1319.25 1319.30 1319.34 1320.70 1320.80 1320.83 1320.85 1320.86 1320.86 1320.92 1320.96 1321.01 1321.09 1321.10 1321.12 1321.21 1321.21 1321.19 1321.26 1321.30 1321.35 1319.96 1321.35 1316.74 1321.40 1321.44 1321.46 1321.40 1321.34 1321.28 1321.23 1321.22 1321.24 1321.26 1321.16 1320.98 1320.83 1320.79 1320.84 1320.87 1320.86 1320.79 1321.54 1321.76 1321.80 1322.16 1322.24 1322.28 1322.25 1322.13 1322.15 1322.17 1322.23 1322.28 --- 1321.51 1322.28 1320.79 1322.32 1322.37 1322.42 1322.44 1322.45 1322.47 1322.49 1322.52 1322.51 1322.48 A 1322.56 1322.49 1322.43 1322.41 1322.40 1322.35 1322.22 1322.10 1321.92 1321.79 1322.07 1322.33 1322.67 1322.50 1322.46 1322.41 1322.38 1322.34 1322.24 1322.14 ___ ___ 1322.04 1321.93 1321.82 1321.72 1321.62 1321.52 1321.40 1321.30 1321.18 1321.08 1320.97 1320.85 1320.73 1320.62 1320.53 1321.79 1321.82 1321.82 1321.74 1321.64 1321.55 1321.55 1321.50 1321.42 1321.36 1321.28 1321.24 1321.14 1321.04 1320.95 1320.89 1321.36 1322.04 1320.53 1320.83 1320.77 1320.72 1320.66 1320.62 1320.64 1320.59 1320.56 1320.50 1320.54 1320.49 1320.43 1320.39 1320.38 1320.35 1320.34 1320.36 1320.51 1320.49 1320.53 1320.51 1320.51 1321.68 1321.76 1321.79 1321.81 1321.81 1321.80 1321.83 1321.82 --- 1320.87 1321.83 1320.34 A No gage-height record 755 RIO DB BAYAMON BASIN 50047560 RIO DB BAYAMON BELOW LAGO 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 AREA.--8.31 mi 1 (21.5 km1 ). 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. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN PEB MAR APR JUN JUL AUG SEP 1 21 21 2 26 22 3 26 24 4 17 9.3 5 9.1 2.6 6 10 10 7 9.9 14 8 10 14 9 10 19 10 28 39 11 41 37 12 26 37 13 20 38 14 20 18 15 20 9.9 16 20 10 17 20 10 18 23 5.0 19 13 2.8 20 6.9 17 21 4.7 23 22 6.8 49 23 6.3 51 24 6.5 32 25 6.3 8.6 26 13 8.7 27 21 12 28 23 9.7 29 23 10 30 22 6.0 31 21 - — TOTAL 530.5 569.6 MEAN 17 . 1 19 . 0 MAX 41 51 MIN 4.7 2.6 AC-PT 1050 1130 CPSM 2.06 2.28 IN. 2.37 2.55 2.5 6.2 19 11 10 11 27 16 11 11 11 21 55 24 9.2 6.1 6.2 6.2 5.9 6.0 16 32 39 41 39 39 9.6 9.2 9.7 9.4 9.5 528.7 17.1 55 2.5 1050 2.05 2.36 STATISTICS OP MONTHLY MEAN DATA MEAN 18.8 33.5 MAX 20.5 41.2 (WY) 1992 1992 MIN 17.1 19.0 (WY) 1993 1993 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 19.9 30.4 1992 12.4 1991 FOR 9.2 9.0 8.8 8.8 8.8 8.6 9.3 8.6 8.5 8.3 8.2 8.1 8.0 8.2 8.0 7.9 8.2 8.3 8.4 8.8 8.5 8.6 8.2 8.1 8.1 8.1 8.2 8.3 7.9 8.0 8.2 260.2 8.39 9.3 7.9 516 1.01 1.16 FOR WATER 27.6 59.6 1992 8.39 1993 8.1 8.2 6.9 5.7 9.7 16 16 15 16 16 14 7.7 5.3 5.4 6.4 11 10 10 6.0 4.1 9.6 9.7 9.7 10 10 14 14 7.1 ___ ___ --- 281.6 10.1 16 4.1 559 1.21 1.26 YEARS 1991 23.3 36.5 1991 10.1 1993 7.1 7.2 7.5 7.2 7.1 6.9 35 22 7.0 8.3 35 35 35 35 17 9.4 9.0 8.3 22 35 26 15 20 35 34 24 16 16 17 16 16 591.0 19.1 35 6.9 1170 2.29 2.64 - 1993 18.7 23.7 1992 13.4 1991 1992 CALENDAR YEAR 7862. 21. 981 . 1. 15600 2. 35. 32 16 5. 71 5 Jan 6 60 Aug 6 7 Aug 3 58 16 8 8.7 33 34 31 23 15 9.3 16 23 11 4.4 4.3 6.6 4.8 11 3.5 3.6 3.8 8.6 12 3.8 3.6 3.6 3.5 3.5 3.6 13 14 11 3.8 --- 330.0 11.0 34 3.5 655 1.32 1.48 5.3 4.1 3.6 3.6 3.7 5.1 3.4 3.8 3.8 3.6 3.6 3.5 3.6 7.7 3.7 3.6 3.5 3.8 3.6 3.8 3.8 .0 .0 .1 .3 .8 .3 .4 .3 .4 .1 127.9 4.13 7.7 3.4 254 .50 .57 4.4 4.3 4.3 29 14 13 14 8.2 4.0 4.2 36 56 55 19 4.0 4.0 16 49 17 4.1 4.0 3.8 3.7 3.6 28 51 3.4 3.6 3.3 3.4 467.3 15.6 56 3.3 927 1.87 2.09 3.3 3.6 5.1 7.0 7.3 7.9 9.5 10 9.9 8.6 632 143 24 13 6.3 5.7 7.7 17 17 17 17 19 11 104 43 19 13 7.9 7.5 15 15 1226.3 39.6 632 3.3 2430 4.75 5.48 16 17 17 16 16 17 16 16 17 16 17 16 16 16 16 12 5.5 5.9 14 14 14 15 15 12 11 12 14 15 15 15 15 449.4 14.5 17 5.5 891 1.74 2.01 15 15 15 14 15 15 15 15 15 15 15 15 13 11 10 9.9 9.9 12 9.4 7.7 5.6 5.5 6.1 5.5 5.2 5.1 7.6 11 11 10--- 334.5 11.1 15 5.1 663 1.34 1.50 , BY WATER YEAR (WY) 15.4 23.0 1992 11.0 1993 FOR 1993 5697. 15. 632 2. 3. 2090 16. 11300 1. 25. 28 10 3. 8.82 12.2 1991 4.13 1993 WATER YEAR 0 6 Jul 11 5 Dec 1 6 May 7 Jul 11 56 Jul 11 88 47 8 15.2 17.8 1992 12.1 1991 23.6 39.6 1993 11.7 1991 WATER 20 24 15 981 1 2090 16 14610 2 32 34 13 4 18.3 27.5 1991 12.8 1992 YEARS 1991 .2 .7 .6 Jan .60 Aug .7 Aug Jul .56 Jul .42 .94 .4 13.8 16.0 1991 11.1 1993 - 1993 1992 1993 6 1992 6 1992 3 1992 11 1993 11 1993 156 RIO DB BAYAMON BASIN 50047560 RIO DB BAYAMON BELOW LAQO CIDRA, PR--Continued HATER-QUALITY RECORDS PERIOD OF RECORDS.-- Water years 1991 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: November 1990 to September 1993. INSTRUMENTATION.— DH-48 and automatic sediment sampler. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATION: Maximum daily mean, 3,670 mg/L Jan. 05, 1992; Minimum daily mean, 6 mg/L Sep. 01, 1991. SEDIMENT LOADS: Maximum daily mean, 9,830 tons (8,920 tonnes) Jan. 05, 1992; Minimum daily mean, 0.04 ton (0.03 tonne) Aug 09-10, 1992. EXTREMES FOR WATER YEAR 1993.-- Hater Year 1993 Suspended-sediment concentration (mg/L) maximum minimum Suspended-sediment discharge (tons per day) maximum minimum 473 (July 24) 13 (Several days) 269 (July 11) SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 .10 (Nov. 05) MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) OCTOBER NOVEMBER MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) 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 29 30 31 21 26 26 17 9.1 10 9.9 10 10 28 41 26 20 20 20 20 20 23 13 6.9 4.7 6.8 6.3 6.5 6.3 13 21 23 23 22 21 194 430 470 438 63 24 21 22 22 22 21 19 18 17 17 17 16 28 19 25 13 14 15 17 22 32 34 24 23 21 19 13 29 32 21 1.6 .79 .56 .56 .57 1.6 2.2 1.4 .90 .88 .88 .85 .79 2.3 .77 .55 .15 .24 .22 .30 .35 1.2 1.7 1.4 1.3 1.2 1.1 21 22 24 9.3 2.6 10 14 14 19 39 37 37 38 18 9.9 10 10 5.0 2.8 17 23 49 51 32 8.6 8.7 12 9.7 10 6.0 17 16 15 14 14 14 13 13 15 39 75 70 36 20 17 14 16 13 17 22 23 23 23 22 19 17 23 15 16 20 .98 .95 .98 .35 .10 .41 .46 .46 .80 3.9 7.5 7.0 3.5 .90 .42 .34 .53 .18 .12 1.1 1.4 3.0 3.1 1.9 .43 .40 1.2 .36 .45 .53 2. 6. 19 11 10 11 27 16 11 11 11 21 55 24 9. 6. 6. 6. 5. 6. 16 32 39 41 39 39 9. 9. 9. 9. 9. 5 2 2 1 2 2 9 0 6 2 7 4 5 15 17 19 21 23 24 25 25 25 25 24 23 21 20 20 20 20 20 20 20 20 20 20 20 20 331 90 87 82 67 56 .11 .28 .99 .61 .62 .72 1.9 1.1 .71 .71 .73 1.2 3.0 1.3 .47 .31 .32 .33 .31 .31 .82 1.8 2.1 2.0 2.1 104 2.4 2.0 2.0 1.6 1.4 TOTAL 530.5 121.36 569.6 43.75 528.7 138.25 RIO DE BAYAMON BASIN 50047560 RIO DE BAYAMON BELOW LAGO CIDRA, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 757 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 9.2 9.0 8.8 8.8 8.8 8.6 9.3 8.6 8.5 8.3 8.2 8.1 8.0 8.2 8.0 7.9 8.2 8.3 8.4 8.8 8.5 8.6 8.2 8.1 8.1 8.1 8.2 8.3 7.9 8.0 8.2 46 49 63 70 60 35 19 14 12 11 10 10 10 12 16 20 28 38 43 41 34 22 14 12 14 18 26 37 41 33 22 1.1 1.2 1.4 1.6 1.3 .77 .45 .31 .26 .23 .22 .22 .21 .26 .33 .41 .59 .81 .92 .94 .77 .51 .29 .24 .30 .37 .56 .79 .85 .70 .48 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) FEBRUARY 8.1 8.2 6.9 5.7 9.7 16 16 15 16 16 14 7.7 5.3 5.4 6.4 11 10 10 6.0 4.1 9.6 9.7 9.7 10 10 14 14 7.1 ___ ___ ___ 12 18 39 55 51 34 19 11 10 10 12 16 19 18 14 12 11 13 14 15 14 13 12 10 10 11 14 14 ___ ___ .26 .37 .66 .79 1.3 1.4 .75 .44 .40 .42 .43 .33 .26 .24 .24 .34 .27 .33 .23 .15 .35 .31 .30 .26 .25 .44 .53 .26 ___ ___ __. MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MARCH 7.1 7.2 7.5 7.2 7.1 6.9 35 22 7.0 8.3 35 35 35 35 17 9.4 9.0 8.3 22 35 26 15 20 35 34 24 16 16 17 16 16 12 8 7 7 7 8 59 40 15 9 60 60 60 60 39 28 27 27 46 58 52 35 42 60 60 48 38 38 38 38 38 .22 .16 .14 .14 .14 .14 5.3 2.4 .26 .33 5.6 5.6 5.5 5.6 2.2 .68 .62 .58 3.5 5.1 3.7 1.5 2.8 5.5 5.4 3.0 1.5 1.6 1.6 1.6 1.6 TOTAL 260.2 19.39 281.6 12.31 591.0 74.01 758 RIO DE BAYAMON BASIN 50047560 RIO DE BAYAMON BELOW LAQO CIDRA, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 8.7 33 34 31 23 15 9.3 16 23 11 4.4 4.3 6.6 4.8 11 3.5 3.6 3.8 8.6 12 3.8 3.6 3.6 3.5 3.5 3.6 13 14 11 3.8 ___ APRIL 26 59 60 58 223 31 13 33 47 45 40 36 45 56 149 18 16 15 15 15 17 20 23 26 31 35 37 35 30 19 ___ .75 5.1 5.4 4.9 10 1.2 .37 1.5 2.9 1.5 .43 .38 1.1 .76 56 .18 .15 .14 .33 .48 .17 .18 .21 .23 .27 .31 1.3 1.3 1.3 .20 ___ MAY 5.3 4.1 3.6 3.6 3.7 5.1 3.4 3.8 3.8 3.6 3.6 3.5 3.6 7.7 3.7 3.6 3.5 3.8 3.6 3.8 3.8 .0 .0 .1 .3 • 8 .3 .4 .3 .4 .1 22 19 18 17 17 20 19 20 24 27 31 32 31 31 24 23 22 20 20 22 24 24 25 25 26 27 25 24 22 21 20 .48 .20 .18 .16 .16 .40 .19 .21 .27 .28 .32 .32 .31 1.3 .25 .23 .22 .23 .22 .23 .26 .28 .29 .30 .31 .40 .32 .30 .27 .27 .25 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) JUNE 4 4 4 29 14 13 14 8 4 4 36 56 55 19 4 4 16 49 17 4 4 3 3 3 28 51 3 3 3 3 .4 .3 .3 .2 .0 .2 .0 .0 .1 .0 .8 .7 .6 .4 .6 .3 .4 20 20 20 51 33 29 25 19 18 18 19 20 24 26 32 37 48 57 67 72 52 32 20 18 25 27 27 23 23 17 .24 .24 .25 6.6 1.2 1.1 .93 .48 .22 .22 1.9 3.1 3.6 1.3 .37 .44 2.2 7.6 3.4 .91 .62 .37 .21 .21 1.9 3.7 .23 .22 .19 .14 TOTAL 330.0 99.04 127.9 9.41 467.3 44.09 RIO DB BAYAMON BASIN 50047560 RIO DB BAYAMON BELOW LAQO CIDRA, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 759 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 3.3 3.6 5.1 7.0 7.3 7.9 9.5 10 9.9 8.6 632 143 24 13 6.3 5.7 7.7 17 17 17 17 19 11 104 43 19 13 7.9 7.5 15 15 1226.3 5697.0 JULY 17 18 19 20 20 19 17 16 15 15 238 31 39 48 57 61 61 60 50 34 18 10 10 473 19 20 22 22 21 37 35 ... MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AUGUST .14 .15 .26 .35 .35 .38 .42 .39 .35 .33 269 12 2.5 1.8 1.0 .84 1.3 2.6 2.2 1.5 .79 .46 .30 172 2.2 1.0 .82 .45 .42 1.4 1.5 479.20 1126.25 16 17 17 16 16 17 16 16 17 16 17 16 16 16 16 12 5.5 5.9 14 14 14 15 15 12 11 12 14 15 15 15 15 449.4 32 29 27 27 29 32 36 39 39 36 34 32 30 29 28 45 57 65 74 80 82 82 81 73 58 46 40 37 35 37 42 ... 1.4 1.2 1.2 1.2 1.2 1.4 1.6 1.7 1.7 1.6 1.5 1.4 1.3 1.2 1.2 1.8 .82 .99 2.7 3.0 3.1 3.1 3.1 2.3 1.6 1.4 1.4 1.4 1.3 1.4 1.6 51.81 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) SEPTEMBER 15 15 15 14 15 15 15 15 15 15 15 15 13 11 10 9.9 9.9 12 9.4 7.7 5.6 5.5 6.1 5.5 5.2 5.1 7.6 11 11 10 334.5 45 45 43 41 42 46 48 44 37 30 27 26 26 26 27 27 27 31 34 40 46 53 70 58 50 49 48 47 46 45 1.7 1.7 1.6 1.5 1.6 1.7 1.8 1.7 1.4 1.1 1.0 1.1 .86 .69 .71 .68 .69 1.2 .80 .75 .68 .77 1.2 .77 .66 .64 .93 1.3 1.2 1.2 33.63 760 RIO DEE BAYAMON BASIN 50047560 RIO DB BAYAMON BELOW LAGO CIDRA PR--Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT DATE DEC 1992 26. .. MAY 1993 06. .. JUL 11. .. DIS- CHARGE, INST. CUBIC FEET TIME PER SECOND 1330 125 1750 6.3 1055 297 SEDI- MENT, SUS- PENDED (MG/L) 4280 1540 1920 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 1440 26 1540 SED. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM 58 70 69 SED. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM 66 79 76 SED. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 76 — 80 DATE DEC 1992 26... MAY 1993 06. .. JUL 11. .. SED. SUSP. FALL DIAM. PERCENT FINER THAN .016 MM 83 85 87 SED. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM 87 91 92 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 98 98.6 99.6 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 98 99.2 99.8 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 99 99.5 99.8 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 100 99.9 99.8 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 100 99.9 100 RIO DB BAYAMON BASIN 50047560 RIO DB BAYAMON BELOW LAGO CIDRA , PR—Continued WATER QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT 767 DATE APR 1993 08... MAY 23... JUL 11... TIME 1730 1630 1025 STREAM- FLOW, INSTAN- TANEOUS (CFS) 32 4.3 135 SEDI- MENT, SUS- PENDED (MG/L) 206 138 1340 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 18 1.6 488 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 99 99 97 162 RIO DB BAYAMON BASIN 50047600 RIO DB BAYAMON NEAR AQUAS BUENAS, PR WATBR-QDALITY RECORDS LOCATION.—Lat 18°14'39", long 66°08'39", at bridge on Highway 156, and 2.9 mi (4.7 km) west of Aguaa Buenas plaza. DRAINAGE AREA.--18.5 mi 1 (47.9 km1 )' PERIOD OF RECORD.--Water years 1958-65, 1974 to current year. HATER-QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 07... DEC 03... FEB 1993 11. .. APR 13... JON 01... SEP 13... TIME 1210 1055 1050 1110 1020 1330 DIS- CHARGE, INST. CUBIC FEET PER SECOND 17 40 26 20 18 31 SPE- CIFIC CON- DUCT- ANCE (US/CM) 285 281 283 218 323 247 PH HATER WHOLE FIELD (STAND- ARD UNITS) 7.7 7.4 8.0 7.4 7.7 7.8 TEMPER- ATURE HATER (DBG C) 25.0 23.0 23.5 23.0 24.5 26.5 TUR- BID- ITY (NTU) 10 74 3.4 17 4.4 6.8 OXYGEN, DIS- SOLVED (MG/L) 8.2 5.6 4.8 7.8 7.4 8.4 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 100 66 57 92 89 105 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) <10 28 <10 17 24 <10 COLI- FORM, FECAL, 0.45 UH-MF (COLS./ 100 ML) K800 K1700 K160 24000 380 590 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 700 3400 300 43000 630 710 DATE OCT 1992 07... DEC 03... FBB 1993 11... APR 13... JUN 01... SEP 13. .. HARD- NESS TOTAL (MG/L AS HARD- NESS NONCARB CALCIUM WH HAT TOT FLD DIS- SOLVED CACO3) CACO3 MG/L AS (MG/L MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS NA) 100 1 25 9.6 15 110 0 26 12 15 99 7 23 10 14 SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY SIUH, HAT WH DIS- SOLVED AS K) 0.6 2.7 0.6 2.9 0.6 2.5 CHLO- SULFATB RIDE, TOT FBT SULFIDB DIS- DIS- FIBLD TOTAL SOLVED SOLVED (MG/L MG/L AS (MG/L CACO3 100 120 110 100 120 130 (MG/L (MG/L AS S) AS SO4) AS CL) 0.8 8.1 16 <0.5 12 19 6.6 15 DATE OCT 1992 07... DEC 03... FBB 1993 11. .. APR 13... JUN 01.. . SEP 13.. . FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.10 -- -- 0.10 -- 0.10 SILICA, DIS- SOLVED (MG/L AS SIO2) 25 -- -- 28 -- 26 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 161 __ -- 175 -- 175 SOLIDS, DIS- SOLVED (TONS PER DAY) 7.41 — — 9.45 — 14.7 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) K l 32 4 144 18 14 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.520 0.290 -- -- 0.590 0.480 NITRO- GEN, NITRITE TOTAL (MG/L AS N) <0.010 0.010 <0.010 <0.010 0.010 0.020 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 0.520 0.300 0.400 0.200 0.600 0.500 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.030 0.020 <0.010 <0.010 0.020 0.010 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.27 0.28 0.39 0.49 1.2 0.29 non-ideal count 163 RIO DB BAYAMON BASIN 50047600 RIO DB BAYAMON NEAR AQUAS BDENAS, PR—Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 07... DEC 03... FEB 1993 11... APR 13... JUN 01... SEP 13... DATE OCT 1992 07... DEC 03... FBB 1993 11.. . APR 13.. . JUN 01.. . SEP 13.. . NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.30 0.30 0.40 0.50 1.2 0.30 IRON, TOTAL RECOV- ERABLE (UG/L AS FE) 430 -- -- 4400 -- -- NITRO- GEN, TOTAL (MG/L AS N) 0.82 0.60 22 0.70 -- 0.60 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) 5 — -- 4 -- -- NITRO- GEN, TOTAL (MG/L AS N03) 3.6 5.8 4.5 3.1 -- 3.5 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) 40 -- -- 190 -- -- PHOS- PHORUS ARSENIC TOTAL TOTAL (MG/L (UG/L AS P) AS AS) 0.050 <1 0.050 3.5 0.110 <1 0.020 0.050 MERCURY TOTAL SBLE- RECOV- NIUM, BRABLB TOTAL (UG/L (UG/L AS HG) AS SB) <0.10 <1 __ -_ <0.10 <1 — — BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 — — <100 -- — — SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) <1 -- -- <1 -- -- BORON, TOTAL RECOV- ERABLE (UG/L AS B) 30 -- -- 40 -- "" ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) <10 -- -- 20 -- -- CHRO- CADMIUM MIUM, TOTAL TOTAL RECOV- RECOV- ERABLE BRABLB (UG/L (UG/L AS CD) AS CR) <1 10 — — <1 9 __ " CYANIDE TOTAL PHENOLS (MG/L TOTAL AS CN) (UG/L) <0.010 1 — __ <0.010 2 __ __ COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) <50 — -- 10 -- " METHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 0.02 -- -- 0.04 -- — 764 RIO DE 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 Bayamon. DRAINAGE AREA.--41.8 mi 1 (108.3 km'). HATER-DISCHARGE RECORDS PERIOD OF RECORD.--September 1964 to October 1970, June 1988 to current year. GAGE.—Hater-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 Guaynabo 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, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 7.3 5.1 2 6.8 3.9 3 6.8 15 4 6.4 96 5 6.4 28 6 7.4 8.1 7 13 7.5 8 12 6.0 9 8.8 6.3 10 14 5.7 11 12 5.1 12 6.4 7.0 13 5.5 25 14 5.2 7.3 15 5.5 92 16 5.1 20 17 5.3 15 18 26 25 19 13 37 20 6.5 13 21 5.6 11 22 7.7 50 23 14 55 24 13 24 25 5.8 15 26 4.8 11 27 4.2 414 28 3.9 164 29 3.8 40 30 4.6 185 31 13 TOTAL 259.8 1397.0 MEAN 8.38 46.6 MAX 26 414 MIN 3.8 3.9 AC-FT 515 2770 CFSM .20 1.11 IN. .23 1.24 26 15 13 13 13 11 11 11 10 10 9.9 10 9.9 29 25 9.1 10 9.8 9.7 8.6 8.3 10 9.7 21 40 611 119 83 169 40 35 1410.0 45.5 611 8.3 2800 1.09 1.25 STATISTICS OF MONTHLY MEAN DATA MEAN 35.1 49.9 MAX 129 174 (HY) 1991 1970 MIN 4.30 7.91 (HY) 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 49.2 263 1966 5.19 1968 FOR 21 19 19 19 27 30 91 63 23 19 18 18 18 17 17 17 16 16 16 16 16 26 41 17 34 18 16 16 16 17 16 733 23.6 91 16 1450 .57 .65 15 15 16 16 16 15 15 15 15 15 15 15 16 16 16 17 19 17 16 18 19 16 15 14 14 14 14 14 ___ ___ --- 438 15.6 19 14 869 .37 .39 FOR HATER YEARS 1964 38.7 159 1969 5.30 1968 22.9 75.3 1989 4.75 1965 14 15 15 14 13 13 13 14 14 13 13 13 13 13 13 16 15 14 13 13 13 13 15 16 15 14 13 12 11 11 11 418 13.5 16 11 829 .32 .37 - 1993 19.7 52.9 1990 3.58 1965 1992 CALENDAR YEAR 10137.8 27.7 1270 3.8 5.5 20110 .66 9.02 40 9.7 7.3 Jan 5 Oct 29 Oct 27 11 11 10 11 11 ell ell e50 e30 e21 elOO e!70 153 89 150 71 19 13 11 121 88 53 19 15 13 12 22 56 138 97 1587 52.9 170 10 3150 1.27 1.41 109 274 127 44 52 63 120 39 143 86 55 37 29 302 91 46 35 32 30 28 27 27 elSl 66 46 e75 120 54 28 23 21 2380 76.8 302 21 4720 1.84 2.12 19 17 17 16 16 15 15 28 45 42 21 18 19 22 18 18 16 18 e!31 el!8 e32 e24 23 22 22 21 21 22 28 24 --- 868 28.9 131 15 1720 .69 .77 21 20 23 23 20 22 59 31 24 24 elSO e60 e30 e25 e25 e21 e!9 e!8 e!7 e!6 16 27 105 314 95 108 49 e25 el8 15 15 1435 46.3 314 15 2850 1.11 1.28 15 14 14 14 14 14 13 13 16 14 13 12 12 13 12 197 28 11 9.6 10 9.8 10 16 10 9.8 9.3 10 10 9.8 9.5 e9.3 572.1 18.5 197 9.3 1130 .44 .51 e9.3 e9.4 e9.2 e9.2 e9.4 e70 e30 e!6 12 9.6 19 10 11 9.4 12 16 11 81 47 96 24 11 14 13 11 10 63 35 22 16--- 715.5 23.8 96 9.2 1420 .57 .64 , BY HATER YEAR (WY) 24.2 72.7 1971 5.36 1965 FOR 1993 12213 33 611 3 5 3250 10 24230 10 87 16 9 50.7 131 1966 6.88 1967 HATER YEAR .4 .5 Dec 26 .8 Oct 29 .5 Oct 27 Dec 26 .47 Dec 26 .80 .87 .2 21.9 60.8 1970 4.26 1967 23.4 46.6 1970 5.98 1967 HATER 35 59 12 5500 2 2 28000 20 25370 11 62 13 5 43.8 137 1970 15.0 1991 YEARS 1964 .0 .7 .1 Oct .2 Apr .4 Apr Oct .20 Oct .84 .38 .0 42.6 146 1989 6.02 1967 - 1993 1966 1968 9 1970 19 1965 14 1965 9 1970 9 1970 e Estimated RIO OB BAYAMON BASIN 50047990 RIO GUAYNABO NEAR BAYAMON, PR HATER-QUALITY RECORDS LOGATION.--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' (189.6 km'). PERIOD OF RECORD.—Hater years 1958, 1964, 1971-73, 1976, 1979 to current year. HATER-QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 165 DATE OCT 1992 06... DEC 07. .. FEB 1993 03... APR 12. .. MAY 25... SEP 01. .. TIME 0820 0900 0830 0750 1205 1225 DIS- CHARGE, INST. CUBIC FEET PER SECOND BIO BIO BIO B20 169 42 SPE- CIFIC CON- DUCT- ANCE (US/CM) 456 464 409 371 191 376 PH HATER WHOLE FIELD (STAND- ARD UNITS) 7.0 6.5 7.6 7.1 6.7 7.5 TEMPER- ATURE HATER (DBG C) 31.0 24.0 24.5 24.0 26.0 28.0 TUR- BID- ITY (NTU) 2.8 9 11 24 140 6.7 OXYGEN, DIS- SOLVED (MG/L) 4.0 4.7 3.6 5.2 5.9 9.1 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 50 55 42 60 71 116 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 12 24 37 12 57 <10 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 3900 4200 460000 49000 60000 60000 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) K620 K2000 27000 48000 22000 310 DATE OCT 1992 06... DEC 07. .. FEB 1993 03. .. APR 12... MAY 25... SEP 01. .. 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, DIS- SODIUM, DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS NA) 160 3 46 12 27 140 6 38 10 23 160 0 41 13 23 SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY CHLO- SIUM, WAT WH SULFATE 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) 0.9 3.5 0.9 4.0 0.8 2.5 CAC03 170 180 130 130 72 170 AS S) AS SO4) AS CL) 0.6 15 0.8 21 15 35 26 24 SOLIDS, RESIDUE DATE OCT 1992 06... DEC 07.. . FBB 1993 03.. . APR 12... MAY 25... SEP 01.. . FLUO- SILICA, RIDE, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS AS F) SI02) 0.20 28 __ __ 0.10 22 __ 0.20 27 SUM OF SOLIDS, CONSTI- DIS- TUENTS , SOLVED DIS- (TONS SOLVED PER (MG/L) DAY) 269 __ __ 222 __ 248 28.1 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) <1 7 12 26 208 12 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.400 0.270 0.930 0.460 0.540 0.240 NITRO- GEN, NITRITE TOTAL (MG/L AS 0. 0. 0. 0. 0. 0. N) 020 030 070 040 060 060 NITRO- GEN, N02+N03 TOTAL (MG/L AS 0 0 1 0 0 0 N) .420 .30 .0 .500 .600 .300 NITRO- GEN, AMMONIA TOTAL (MG/L AS 0. 3. 0. 0. 0. 0. N) 060 10 010 010 010 010 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.34 0.80 0.69 0.49 0.69 0.39 B = estimate K = non-ideal count 766 DATE OCT 1992 06... DEC 07... FEB 1993 03.. . APR 12... MAY 25... SEP 01.. . DATE OCT 1992 06... DEC 07... FEB 1993 03.. . APR 12.. . MAY 25.. . SEP 01.. . RIO DE BAYAMON BASIN 50047990 RIO GUAYNABO NEAR BAYAMON, PR—Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.40 3.9 0.70 0.50 0.70 0.40 IRON, TOTAL RECOV- ERABLE (UG/L AS FE) NITRO- GEN, TOTAL (MG/L AS N) 0.82 4.2 3.9 3.4 1.7 2.3 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS NO3) 3.6 19 15 7.5 10 13 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.230 0.870 0.270 0.170 0.170 0.140 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) ARSENIC TOTAL (UG/L AS AS) 2 -- — 1 -- -- SELE- NIUM, TOTAL (UG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) 200 -- -- <100 — — SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) 50 — -- 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) 3 -- — <1 -- -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) <10 — — 10 -- — MBTHY- LENB BLUE ACTIVE SUB- STANCE (MG/L) 390 1200 14 210 170 0.20 <0.10 20 <0.010 <0.010 0.07 0.08 167 RIO DB BAYAMON BASIN 50048510 RIO DB BAYAMON AT FLOOD CHANNEL AT BAYAMON, PR HATER-QUALITY RECORDS LOCATION.--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 1 (186.2km 1 ). PERIOD OF RECORD.--Hater years 1974 to current year. REMARKS.--Prior to 1979 sampling site was 0.8 mile (1.3 km) downstream but was changed because of flood channel construction. WATER-QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 06... DEC 07... FEB 1993 03... APR 12... MAY 26... SEP 01... TIME 1045 1120 1010 1005 1135 1430 DIS- CHARGE, INST. CUBIC FEET PER SECOND 12 37 57 104 104 40 SPE- CIFIC CON- DUCT- ANCE (US/CM) 427 441 430 305 369 383 PH HATER WHOLE FIELD (STAND- ARD UNITS) 7.5 6.6 7.6 7.1 7.0 8.0 TEMPER- ATURE WATER (DBG C) 31.0 26.0 25.0 25.0 26.5 30.0 TUR- BID- ITY (NTU) 1.2 22 3.2 120 18 3.7 OXYGEN, DIS- SOLVED (MG/L) 7.4 6.0 5.0 6.6 5.9 6.9 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 89 73 56 90 79 92 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 21 13 19 14 15 <10 COLI- FORM, FECAL, 0.45 UM-MP (COLS./ 100 ML) 53000 1600 670000 54000 330000 2400 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 40 280 2400 49000 3000 220 DATE OCT 1992 06. .. DEC 07. .. FBB 1993 03... APR 12... MAY 26. .. SEP 01. .. HARD- HARD- NESS MAGNE- NESS NONCARB CALCIUM SIUM, SODIUM, TOTAL WH HAT DIS- DIS- DIS- (MG/L TOT FLD SOLVED SOLVED SOLVED AS MG/L AS (MG/L (MG/L (MG/L CACO3) CAC03 AS CA) AS MG) AS NA) 170 7 45 14 23 110 6 30 9.2 19 150 1 39 12 21 SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY SIUM, HAT WH DIS- SULFATB TOT FBT SULFIDB DIS- SOLVED FIELD AS K) 0.8 2.5 0.8 3.3 0.8 2.4 CACO3 190 180 170 100 140 160 TOTAL (MG/L MG/L AS (MG/L SOLVED (MG/L <0.5 17 <0.5 16 15 CHLO- RIDE, DIS- SOLVED (MG/L AS S) AS SO4) AS CL) 31 21 25 SOLIDS, RESIDUE DATS OCT 1992 06.. . DEC 07... FEB 1993 03... APR 12... MAY 26... SEP 01.. . FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.20 -- -- 0.10 -- 0.20 SILICA, DIS- SOLVED (MG/L AS SIO2) 27 -- -- 20 -- 27 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 274 -- -- 179 -- 212 SOLIDS, DIS- SOLVED (TONS PER DAY) 8.87 -- -- 50.1 -- 22.9 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 1 12 5 129 32 10 NITRO- GEN, NITRATE TOTAL (MG/L AS N) -- 0.440 0.410 0.340 0.740 0.410 NITRO- GBN, NITRITE TOTAL (MG/L AS N) <0.010 0.160 0.090 0.060 0.060 0.090 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) <0.050 0.600 0.500 0.400 0.800 0.500 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) <0.010 1.40 1.00 0.010 0.110 0.240 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.40 0.70 1.2 1.1 0.30 1.1 non-ideal count 168 DATE OCT 1992 06... DEC 07.. . FEE 1993 03... APR 12.. . MAY 26.. . SEP 01... DATE OCT 1992 06.. . DEC 07... FBB 1993 03.. . APR 12.. . MAY 26... SEP 01... RIO DB BAYAMON BASIN 50048510 RIO DB BAYAMON AT FLOOD CHANNEL AT BAYAMON, PR—Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.40 2.1 2.2 1.1 0.4 1.3 IRON, TOTAL RECOV- ERABLE (UG/L AS FE) NITRO- GEN, TOTAL (MG/L AS N) 1.6 2.7 2.7 2.5 1.2 1.8 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS NO3) 12 9 14 5 11 7 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.320 0.260 0.440 0.130 0.160 0.370 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) 40 -- -- 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) <1 -- -- 2 -- -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) <10 — — 20 -- — MBTHY- LENB BLUE ACTIVE SUB- STANCE (MG/L) 430 4000 270 210 <0.10 <0.10 20 <0.010 20 <0.010 0.05 0.06 RIO PUERTO NUEVO BASIN 50048770 RIO PIEDRAS AT EL SBNORIAL, PR LOCATION.—Lat 18°21'51", long 66<>03'56*, Hydrologic Unit 21010005, on right bank, in the Riberas 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. 169 DRAINAGE AREA.--7.49 mi' (19.40 km'). 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 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, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEE MAR APR MAY JUN JUL AUG SEP 1 15 54 2 14 20 3 14 143 4 17 292 5 15 40 6 13 21 7 14 13 8 95 10 9 32 18 10 89 14 11 25 11 12 16 14 13 13 21 14 14 12 15 13 24 16 21 11 17 14 59 18 18 277 19 11 36 20 13 36 21 13 27 22 23 67 23 14 32 24 26 29 25 14 24 26 10 21 27 12 122 28 11 213 29 10 41 30 41 91 31 29 TOTAL 679 1793 MEAN 21.9 59.8 MAX 95 292 KEN 10 10 AC-FT 1350 3560 CFSM 2.92 7.98 IN. 3.37 8.91 23 14 17 13 8.7 8.4 7.8 7.7 7.7 8.3 9.1 9.2 11 159 68 22 18 19 16 14 16 21 23 68 65 240 62 88 143 46 24 1256.9 40.5 240 7.7 2490 5.41 6.24 STATISTICS OF MONTHLY MEAN DATA MEAN 29.3 25.2 MAX 57.3 59.8 i[WY) 1991 1993 MIN 8.48 7.51 i[WY) 1992 1991 JJUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN I/WEST ANNUAL MEAN HIGHEST DAILY MEAN I/WEST 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 !iO PERCENT EXCEEDS 5)0 PERCENT EXCEEDS 18.0 40.5 1993 8.69 1992 FOR 16 18 17 16 18 21 111 24 16 15 17 20 16 14 14 14 13 13 11 11 11 69 23 12 41 11 9.8 9.6 14 11 8.1 634.5 20.5 111 8.1 1260 2.73 3.15 7.8 7.2 7.2 e6.8 e6.2 e6.4 e6.2 e6.0 e6.0 e5.6 e6.6 e7.6 e6.0 e5.0 e4.8 e4.6 7.9 6.2 5.2 8.0 6.1 5.3 5.8 5.6 5.8 5.9 4.4 4.4 ___ ___ 170.6 6.09 8.0 4.4 338 .81 .85 FOR HATER YEARS 1988 17.1 24.4 1992 12.1 1989 13.3 23.6 1991 6.09 1993 4.3 5.5 5.1 5.3 5.3 5.1 .5 .2 .8 .5 .3 .1 .3 3.4 3.1 25 5.3 6.0 5.8 4.0 3.2 4.7 8.9 e!68 e!9 8.4 7.9 6.1 6.2 6.3 7.5 360.1 11.6 168 3.1 714 1.55 1.79 - 1993 12.2 19.5 1990 7.68 1992 1992 CALENDAR YEAR 10350. 28. 621 1. 3. 20530 3. 51. 68 10 4. 3 3 Aug 21 6 Apr 15 1 Apr 12 78 41 5 7.7 7.5 7.7 7.1 7.6 6.6 8.3 30 7.6 6.5 e78 12 57 24 7.6 6.4 5.7 4.4 4.4 34 e90 17 6.1 4.7 6.5 4.8 4.4 27 e!62 e65 717.6 23.9 162 4.4 1420 3.19 3.56 , BY HATER 15.5 23.9 1993 10.4 1991 16 11 71 22 13 15 49 24 17 21 16 11 9.6 20 9.1 6.4 6.2 5.5 5.4 6.1 8.8 7.1 43 36 14 23 74 57 18 11 7.2 653.4 21.1 74 5.4 1300 2.81 3.25 YEAR (HY) 20.9 47.2 1992 9.09 1989 6.5 7.0 7.1 6.1 6.5 4.9 5.7 28 43 11 8.2 7.7 17 20 10 8.2 7.4 8.8 177 62 14 10 8.6 8.4 6.0 6.2 7.0 7.2 24 14--- 557.5 18.6 177 4.9 1110 2.48 2.77 14.8 24.8 1989 8.74 1990 FOR 1993 HATER YEAR 8789.4 24.1 359 3.1 4.1 3540 13.45 17430 3.22 43.65 58 11 5.1 Jul 11 Mar 15 Mar 9 Nov 18 Nov 18 7.3 31 22 10 8.7 7.8 129 20 13 11 359 42 18 12 11 10 6.2 5.1 8.1 5.4 5.2 85 110 55 13 133 19 6.6 5.2 5.1 5.6 1179.3 38.0 359 5.1 2340 5.08 5.86 19.6 38.0 1993 7.43 1990 HATER 19. 24. 15. 621 1. 2. 4680 16. 14290 2. 35. 42 8. 4. 6.3 6.3 6.1 5.4 5.8 6.5 5.9 5.7 6.7 5.3 5.6 4.8 4.4 6.2 6.1 15 6.3 5.5 5.2 4.8 6.7 6.0 5.3 4.9 4.9 4.5 4.6 5.0 e!20 14 14 313.8 10.1 120 4.4 622 1.35 1.56 26.1 66.9 1992 6.60 1990 YEARS 1988 - 7 1 7 Aug 21 6 Apr 15 7 Aug 8 Aug 24 08 Aug 24 63 79 7 7 8.0 13 7.6 6.4 23 e83 12 8.8 6.2 41 7.6 5.7 21 6.8 6.9 6.0 51 27 9.4 5.7 16 7.0 14 6.5 6.0 4.9 5.6 32 6.6 19 473.7 15.8 83 4.9 940 2.11 2.35 25.5 59.5 1989 6.90 1991 1993 1993 1990 1992 1992 1991 1988 1988 e Estimated 170 RIO PUERTO NUBVO BASIN 50048770 RIO PIEDRAS AT EL SENORIAL, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORDS.-- Water years 1988 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGES April 1988 to September 1993. INSTRUMENTATION.— USD-77 and automatic sediment sampler. EXTREMES FOR PERIOD OF DAILY RECORD.— SEDIMENT CONCENTRATIONS Maximum daily mean, 24,600 mg/L Sep. 18, 1989; Minimum daily mean, 2 mg/L November 18, 1988. SEDIMENT LOADSi Maximum daily mean, el!4,000 tons (e!03,000 tonnes) Sep. 18, 1989; Minimum daily mean, 0.04 ton (0.03 tonne) May 6, 1990. EXTREMES FOR WATER YEAR 1993.-- SBDIMBNT CONCENTRATIONS Maximum daily mean, 6,300 mg/L Mar. 24, 1993; Minimum daily mean, 22 mg/1 several days. SEDIMENT LOADSi Maximum daily mean, e28,400 tons (e25,000 tonnes) Mar. 24, 1993; Minimum daily mean, 0.18 ton (0.16 tonne) Mar. 15, 1993. SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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) MEAN MEAN F CONCEN- SEDIMENT MEAN CONCEN- SEDIMENT .GE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE (MG/L) (TONS/DAY) (CFS) (MG/L) (TONS/DAY) 15 14 14 17 15 13 14 95 32 89 25 16 13 14 13 21 14 18 11 13 13 23 14 26 14 10 12 11 10 41 29 OCTOBER 122 109 106 189 137 114 114 1860 405 1460 293 143 102 120 89 272 104 237 116 112 90 305 104 320 129 100 100 103 86 624 340 NOVEMBER 5.0 4.0 4.0 16 5.6 3.7 4.1 3110 43 1150 24 6.9 3.6 5.1 3.5 49 3.8 29 4.0 4.0 2.9 46 3.5 75 5.1 3.5 3.7 3.8 2.7 361 59 54 20 143 292 40 21 13 10 18 14 11 14 21 12 24 11 59 277 36 36 27 67 32 29 24 21 122 213 41 91 ___ 926 265 3030 6300 557 262 143 120 293 159 101 139 261 107 350 119 2220 5060 523 566 366 971 394 372 300 263 2280 4360 558 1580 ___ 705 63 4430 10300 86 22 6.7 3.8 25 7.7 3.3 13 28 3.8 146 4.0 920 25000 66 275 88 239 39 42 28 19 1600 10800 81 845 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) DECEMBER 23 14 17 13 8.7 8.4 7.8 7.7 7.7 8.3 9.1 9.2 11 159 68 22 18 19 16 14 16 21 23 68 65 240 62 88 143 46 24 232 132 198 142 67 66 68 68 68 68 66 73 113 3180 998 222 170 206 174 144 166 251 281 1130 1030 4910 927 1510 2910 621 178 14 4.9 21 12 1.6 1.4 1.4 1.4 1.4 1.4 1.7 1.9 8.8 7170 445 13 7.6 15 8.3 5.6 8.2 17 21 572 352 5410 203 732 4310 98 12 TOTAL 679 5044.5 1793 55889.3 1256.9 19472.6 RIO PUERTO NOEVO BASIN 50048770 RIO PIBDRAS AT EL SBNORIAL, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 171 MEAN DISCHARGE )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 (CPS) 16 18 17 16 18 21 111 24 16 15 17 20 16 14 14 14 13 13 11 11 11 69 23 12 41 11 9. 9. 14 11 8. 8 6 1 MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) JANUARY 124 124 198 187 210 211 2070 273 145 188 188 230 159 120 114 114 108 102 102 102 96 1140 292 162 679 92 77 75 122 88 64 TOTAL 634.5 5.5 5.7 9.3 8.4 14 18 2430 20 5.7 7.3 8.3 19 8.6 4.1 4.6 4.6 3.4 3.7 3.0 3.0 2.7 495 26 6.5 349 2.6 2.1 1.9 6.5 2.7 1.3 3482.5 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) FEBRUARY 7.8 7.2 7.2 e6.8 e6.2 e6.4 e6.2 e6.0 e6.0 e5.6 e6.6 e7.6 e6, e5, e4.8 e4.6 7.9 6.2 5.2 8.0 6.1 5.3 5.8 5.6 5.8 5.9 4.4 4.4 170.6 64 57 40 58 56 54 51 50 50 46 56 66 50 40 38 36 61 35 33 70 36 34 33 31 30 33 34 34 1.3 1.1 .78 el.l e.94 e.94 e.86 e.82 e.82 e.70 el.O el. 4 e.82 e.54 e.50 e.44 2.9 .56 .46 1.9 .64 .48 .50 .45 .49 .55 .40 .40 MEAN DISCHARGE (CPS) 4.3 5.5 5.1 5.3 5.3 5.1 .5 .2 .8 .5 .3 .1 .3 3.4 3.1 25 5.3 6.0 5.8 4.0 3.2 4.7 8.9 e!68 e!9 8.4 7.9 6.1 6.2 6.3 7.5 MEAN CONCEN- TRATION (MG/L) MARCH 27 30 29 28 26 27 26 25 23 23 23 22 22 23 22 342 39 24 30 28 24 23 92 6300 301 82 41 38 37 37 43 SEDIMENT DISCHARGE (TONS/DAY) .32 .44 .39 .37 .37 .39 .34 .30 .29 .27 .27 .25 .28 .20 .18 128 .64 .37 .47 .29 .21 .30 5.8 e28400 e560 2.0 .84 .65 .66 .66 .89 23.79 360.1 29106.44 e Estimated 772 RIO PUERTO NUEVO BASIN S0048770 RIO PIEORAS AT EL SENORIAL, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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 7.7 7.5 7.7 7.1 7.6 6.6 8.3 30 7.6 6.5 e78 12 57 24 7.6 6.4 5.7 4.4 4.4 34 e90 17 6.1 4.7 6.5 4.8 4.4 27 e!62 e65 APRIL 52 53 52 55 55 54 80 466 64 30 1780 110 971 219 51 36 26 23 22 512 2100 210 55 34 65 29 23 401 3590 1020 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MAY 1 1 1 1 2 229 1 e3190 3 512 19 1 170 e3640 13 1 4 146 e9970 e363 .0 .1 .1 .95 .0 .94 .5 .7 .57 .9 .2 .69 .39 .25 .25 .0 .41 .8 .38 .26 16 11 71 22 13 15 49 24 17 21 16 11 9.6 20 9.1 6.4 6.2 5.5 5.4 6.1 8.8 7.1 43 36 14 23 74 57 18 11 7.2 185 102 1240 257 120 154 796 262 259 332 167 79 226 243 83 47 45 48 48 44 97 70 730 526 146 293 1280 970 191 116 60 11 3.8 909 21 4.5 9.9 484 29 17 24 8.0 2.4 6.5 25 2.3 .80 .79 .74 .74 .72 6.9 1.6 483 134 6.6 46 598 499 11 4.3 1.2 6 7 7 6 6 4 5 28 43 11 8 7 17 20 10 8 7 8 177 62 14 10 8 8 6 6 7 7 24 14 - JUNE .5 .0 .1 .1 .5 .9 .7 .2 .7 .2 .4 .8 .6 .4 .0 .2 .0 .2 -- 51 53 72 31 36 37 42 421 2110 94 68 63 200 226 107 64 61 95 2820 590 142 82 72 74 59 44 44 46 373 152 ___ .83 .99 1.4 .46 .56 .47 .59 166 1640 2.8 1.6 1.4 28 32 3.5 1.5 1.3 5.0 2180 155 6.2 2.1 1.6 1.7 1.2 .72 .75 .88 114 6.5 ___ TOTAL 717.6 18276.39 653.4 3352.79 557.5 4359.05 e Estimated RIO PUERTO NUBVO BASIN 50048770 RIO PIBDRAS AT BL SENORXAL, PR—Continued SBDIMKNT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 773 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) 7.3 31 22 10 8.7 7.8 129 20 13 11 359 42 18 12 11 10 £.2 5.1 8.1 5.4 5.2 85 110 55 13 133 19 6.6 5.2 5.1 5.6 MEAN CONCEN- TRATION (MG/L) JULY 66 453 276 106 88 58 2560 217 151 124 7590 529 218 133 116 112 53 42 77 41 43 1660 1810 833 133 2570 206 53 40 39 39 TOTAL 1179.3 --- YEAR e 8789.4 Estimated SEDIMENT DISCHARGE (TONS/DAY) 1.3 123 36 3.5 2.5 1.0 5760 13 6.3 4.6 16900 83 11 5.1 4.1 3.6 .92 .59 2.9 .55 .75 1950 1090 270 6.1 2960 16 .95 .54 .50 .62 29258.42 173655.02 MEAN DISCHARGE (CFS) 6.3 6.3 6.1 5.4 5.8 6.5 5.9 5.7 6.7 5.3 5.6 4.8 4.4 6.2 6.1 15 6.3 5.5 5.2 4.8 6.7 6.0 5.3 4.9 4.9 4.5 4.6 5.0 e!20 14 14 313.8 MEAN CONCEN- TRATION (MG/L) AUGUST 36 64 40 42 42 69 54 46 66 58 37 36 34 66 55 183 51 44 41 39 69 42 42 37 39 37 36 49 1610 146 170 —— SEDIMENT DISCHARGE (TONS/DAY) MEAN DISCHARGE (CFS) MEAN CONCEN- TRATION (MG/L) SEDIMENT DISCHARGE (TONS/DAY) SEPTEMBER .58 1.3 .72 .59 .59 1.5 1.0 .70 1.6 .95 .58 .43 .40 1.6 1.0 15 .85 .64 .55 .50 1.2 .59 .59 .46 .50 .47 .43 .90 e2470 6.6 22 2534.82 8.0 13 7.6 6.4 23 e83 12 8.8 6.2 41 7.6 5.7 21 6.8 6.9 6.0 51 27 9.4 5.7 16 7.0 14 6.5 6.0 4.9 5.6 32 6.6 19--- 473.7 66 143 66 56 323 673 123 92 56 702 65 48 329 46 59 54 969 354 87 37 193 54 173 77 41 46 34 482 60 273 —— 1.4 12 1.4 1.0 85 e819 5.4 3.7 1.0 518 1.5 .72 85 .84 1.2 1.0 948 77 3.1 .61 47 .94 24 1.5 .62 .73 .46 143 1.3 68—— 2854.42 174 RIO PUERTO NUBVO BASIN 50048770 RIO PIBDRAS AT EL SBNORIAL, PR--Continued HATER QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 PARTICLE-SIZE DISTRIBUTION OP SUSPENDED SEDIMENT DATE APR 1993 20... JUN 19... DIS- CHARGE, INST. CUBIC FEET TIME PER SECOND 1345 833 0958 366 SEDI- MENT, SUS- PENDED (MG/L) 3480 26200 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 8640 25800 SBD. SUSP. PALL DIAM. PERCENT FINER THAN .002 MM 38 27 SBD. SUSP. PALL DIAM. PERCENT FINER THAN .004 MM 45 38 SBD. SUSP. PALL DIAM. PERCENT FINER THAN .008 MM 58 44 DATE APR 1993 20... JUN 19. .. SED. SUSP. PALL DIAM. PERCENT FINER THAN .016 MM 73 58 SBD. SUSP. PALL DIAM. PERCENT FINER THAN .031 MM -- 71 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 96 84 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 98 91 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 99.3 96 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 99.9 99 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 100 100 RIO PUERTO NUEVO BASIN 50048770 RIO PIBDRAS AT BL SENORIAL, PR--Continued WATER QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT 175 DATE MAY 1993 10.. . OUN 19... 19... TIME 1130 0858 2120 STREAM- FLOW, INSTAN- TANEOUS (CFS) 12 188 205 SEDI- MENT, SUS- PENDED (MG/L) 149 7240 4810 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 4.8 3670 2660 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 99 69 981 176 RIO PUERTO NUBVO BASIN 50048800 RIO PIEDRAS NEAR RIO PIBDRAS, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°22 / 15", long 66°03'40", at bridge on Winston Churchill Avenue in the El Seflorial Housing area, 0.5 mi (0.8 km) west of Highway 176, and 2.5 mi (4.0 km) southwest of Rio Piedras plaza. DRAINAGE AREA.--8.17 mi 1 (20.9 km1 ). PERIOD OF RECORD.—Water years 1972 to current year. WATER QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 01. .. DEC 15... FEB 1993 11. .. APR 07. .. JUN 01. .. AUG 04. .. TIME 0915 0930 0900 1335 1145 1350 DIS- CHARGE, INST. CUBIC FEET PER SECOND 8.0 21 5.7 4.7 6.1 6.3 SPE- CIFIC CON- DUCT- ANCE (US/CM) 376 275 460 410 440 414 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.8 7.2 7.8 7.8 7.9 7.7 TEMPER- ATURE WATER (DEG C) 25.5 24.0 21.6 30.5 31.0 31.0 TUR- BID- ITY (NTU) 26 2.7 94 1.8 5.1 0.80 OXYGEN, DIS- SOLVED (MG/L) 7.3 6.3 7.3 10.9 7.8 9.0 OXYGEN, OXYGEN DIS- DEMAND, SOLVED CHBM- (PER- ICAL CENT (HIGH SATUR- LEVEL) ATI ON) (MG/L) 88 <10 79 <10 87 <10 143 <10 100 21 120 12 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 230000 K8000 600000 K10000 300000 14000 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) K12700 13000 7400 K1200 120000 3600 DATE OCT 1992 01. .. DEC 15. .. FEB 1993 11. .. APR 07. .. JUN 01. .. AUG 04... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MG/L TOT FLD SOLVED AS MG/L AS (MG/L CAC03) CACO3 MAGNE- SIUM, DIS- SODIUM, DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS NA) 130 0 38 9.6 20 160 4 42 13 29 160 7 41 13 29 SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY CHLO- SIUM, WAT WH SULFATE RIDE, DIS- TOT PET SULFIDE DIS- DIS- SOLVED FIELD TOTAL SOLVED SOLVED (MG/L MG/L AS (MG/L (MG/L (MG/L AS K) 0.8 3.1 1 2.9 1 2.6 CAC03 115 120 150 160 180 100 AS S) AS S04) AS CL) <0.5 28 <0.5 16 21 28 33 29 SOLIDS, RESIDUE DATE OCT 1992 01.. . DEC 15.. . FEB 1993 11.. . APR 07.. . JUN 01.. . AUG 04.. . PLUO- RIDE, DIS- SOLVED (MG/L AS F) 0.20 -- -- 0.20 -- 0.20 SILICA, DIS- SOLVED (MG/L AS SIO2) 24 -- -- 31 -- 32 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 220 -- -- 263 -- 228 SOLIDS, DIS- SOLVED (TONS PER DAY) 4.72 — __ 3.32 — 3.87 TOTAL AT 105 DEG. C, SUS- PENDED (MG/L) 7 1 __ 9 38 2 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.680 0.780 0.600 0.790 0.680 0.570 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.040 0.020 0.090 0.060 0.070 0.070 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 0.720 0.800 0.690 0.850 0.750 0.640 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.220 0.030 0.300 0.180 0.590 0.290 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.38 0.17 0.50 0.42 0.41 0.51 non-ideal count 177 RIO PUERTO NOBVO BASIN 50048800 RIO PIBDRAS NEAR RIO PIBDRAS, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 OCT 1992 01... DEC 15... FEE 1993 11... APR 07... JUN 01... AUG 04... 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 CU) 0.60 0.40 0.80 0.60 1.0 0.80 1.3 4.1 1.5 1.5 1.7 1.4 5.8 18 6.6 6.4 7.7 6.4 0.170 0.810 0.290 0.320 0.280 0.260 200 200 40 50 DATE OCT 1992 01... DEC 15.. . FBB 1993 11... APR 07... JUN 01... AUG 04... IRON, TOTAL RECOV- ERABLE (DG/L AS FE) 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 (UG/L AS AG) ZINC, TOTAL RECOV- ERABLE (DG/L AS ZN) CYANIDE TOTAL (MG/L AS CN) PHENOLS TOTAL (UG/L) MBTHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 1400 150 <1 <1 150 110 <0.10 <0.10 <1 <1 <1 <1 20 <0.010 10 <0.010 <1 <1 0.05 0.19 PESTICIDE ANALYSES DATE JUN 1993 08... TIME 1115 PCB, TOTAL (UG/L) ALDRIN, TOTAL (UG/L) <0.010 CHLOR- DANB, TOTAL (UG/L) ODD, TOTAL (UG/L) DDE, TOTAL (UG/L) DDT, TOTAL (UG/L) <0.010 <0.010 <0.010 DI- AZINON, TOTAL (UG/L) DI- ENDO- BLDRIN SULFAN, TOTAL TOTAL (UG/L) (UG/L) 0.06 <0.010 <0.010 ENDRIN WATER UNFLTRD ETHION, DATE RBC TOTAL (UG/L) (UG/L) JUN 1993 08... HEPTA- HEPTA- 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) 0.05 MBTH- OXY- CHLOR, TOTAL (UG/L) <0.01 METHYL PARA- THION, TOTAL (UG/L) <0.01 MIRBX, TOTAL (UG/L) <0.01 DATE JUN 1993 08... PARA- THION, TOTAL <0.01 NAPH- THA- LENES, POLY- CHLOR. TOTAL (UG/L) (UG/L) <0.10 PBR- THANB TOTAL (UG/L) TOX- APHENB, TOTAL (UG/L) <1 TOTAL TRI- THION (UG/L) <0.01 2,4-D, 2,4,5-T 2, 4-DP SILVEX, TOTAL TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) (UG/L) 0.04 <0.01 <0.01 <0.01 178 RIO PUERTO NUBVO BASIN 50049000 RIO PIEDRAS AT RIO PIBDRAS, PR LOCATION.—Lat 18023'48", long 66«03'24", Hydrologic Unit 21010005, on left bank, at bridge on Highway 1, 0.3 mi (0.5 km) southwest of the plaza in Rio Piedras, and 0.4 mi (0.6 km) downstream from diversion for water supply. DRAINAGE AREA.--12.5 mi' (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, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 8.2 41 2 9.9 19 3 8.2 187 4 15 866 5 7.0 58 6 5.8 40 7 6.7 30 8 68 28 9 14 35 10 47 29 11 12 21 12 8.1 49 13 6.8 39 14 13 21 15 8.1 40 16 35 20 17 9.4 75 18 26 443 19 7.0 70 20 8.6 139 21 8.5 60 22 18 137 23 32 53 24 22 47 25 11 39 26 8.3 33 27 26 167 28 8.1 369 29 8.1 90 30 115 86 31 20 TOTAL 600.8 3331 MEAN 19.4 111 MAX 115 866 MIN 5.8 19 AC-FT 1190 6610 CFSM 1.55 8.88 IN. 1.79 9.91 STATISTICS OF MONTHLY MEAN MEAN 48.2 39.9 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 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 27 19 24 27 16 15 13 12 10 10 10 10 12 423 139 23 21 22 21 16 19 26 27 106 61 313 70 104 169 51 30 1846 59.5 423 10 3660 4.76 5.49 DATA 36.6 133 1976 9.88 1977 FOR 26 32 32 30 41 44 140 35 28 28 29 38 30 32 18 15 15 16 16 15 17 93 22 18 35 17 17 15 17 13 12 936 30.2 140 12 1860 2.42 2.79 12 13 16 12 12 11 12 13 12 13 11 15 8.8 8.2 10 11 21 11 12 22 13 11 12 11 13 12 11 11 --_ --- 350.0 12.5 22 8.2 694 1.00 1.04 FOR WATER YEARS 1971 18.2 34.7 1992 4.03 1973 19.8 98.9 1979 4.40 1977 12 11 11 12 12 13 12 11 11 12 11 11 11 10 9.9 47 14 12 12 11 11 13 20 226 25 14 14 13 13 13 13 640.9 20.7 226 9.9 1270 1.65 1.91 - 1993 16.4 42.5 1972 2.67 1976 1992 CALENDAR YEAR 14166.0 38.7 866 4.8 6.1 28100 3.10 42.16 97 12 6.9 Nov 4 Sep 28 Sep 8 12 12 13 12 12 11 16 47 14 12 95 17 44 36 14 12 20 11 10 41 132 18 10 9.3 9.8 9.6 8.9 35 361 105--- 1159.6 38.7 361 8.9 2300 3.09 3.45 14 12 46 15 11 14 71 21 18 18 13 11 10 19 11 9.3 9.2 8.6 8.6 9.1 10 9.3 87 41 18 28 146 40 13 10 8.6 759.7 24.5 146 8.6 1510 1.96 2.26 8.3 8.7 9.1 8.7 9.1 8.5 8.4 22 37 19 12 12 31 19 38 11 10 10 206 53 14 14 11 13 10 9.6 9.8 9.7 20 9.5 --- 661.4 22.0 206 8.3 1310 1.76 1.97 7.6 23 23 9.4 9.5 9.9 158 17 12 12 474 37 18 17 21 15 13 12 14 11 11 123 126 54 15 118 24 12 11 12 11 1430.4 46.1 474 7.6 2840 3.69 4.26 11 11 11 10 9.8 9.9 9.8 9.7 10 9.3 9.3 9.4 8.9 10 11 17 8.5 8.4 8.3 8.1 8.7 9.0 8.1 7.9 7.9 7.6 8.1 8.5 65 12 9.5 352.7 11.4 65 7.6 700 .91 1.05 7.2 8.9 8.6 8.5 18 184 16 14 9.2 42 11 9.6 21 11 11 11 61 21 21 9.5 20 10 17 11 9.0 9.8 13 21 9.7 15 639.0 21.3 184 7.2 1270 1.70 1.90 , BY WATER YEAR (WY) 24.7 64.0 1978 4.49 1974 FOR 1993 12707. 34. 866 5. 8. 5960 13. 25210 2. 37. 69 13 8. 32.1 121 1979 3.46 1975 WATER YEAR 5 8 Nov 4 8 Oct 6 2 Aug 22 Apr 29 02 Apr 29 79 82 7 19.1 59.7 1989 3.25 1974 22.1 55.6 1989 3.35 1976 WATER 29. 54. 11. 2030 . . 10000 21. 21350 2. 32. 53 12 3. 36.8 120 1979 4.30 1976 YEARS 1971 - 5 2 9 Feb 15 26 May 19 83 Aug 14 Dec 11 02 Dec 11 36 03 4 37.1 112 1989 10.1 1973 1993 1979 1974 1979 1977 1976 1975 1975 RIO PUERTO NUEVO BASIN 50049000 RIO PIBORAS AT RIO PIBORAS, PR—Continued WATER-QUALITY RECORDS PERIOD OF RECORDS.— Water years 1988 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: October 1988 to September 1993. INSTRUMENTATION.— USD-77 and automatic sediment sampler. 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 YEAR 1993.-- SEDIMENT CONCENTRATION: Maximum daily mean, 4,460 mg/L Nov. 04, 1992; Minimum daily mean, 9 mg/L Aug. 23, 1993. SEDIMENT LOADSt Maximum daily mean, 21,200 tons (19,200 tonnes) Nov. 04, 1992; Minimum daily mean, 0.18 tons (0.16 tonnes) Aug. 23, 1993. 179 SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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 20 12 9.9 9.7 12 7.0 6.5 8.8 5.9 5.4 5.4 5.5 5.7 4.8 7.3 5.8 4.9 66 13 7.9 6.9 6.5 8.7 6.9 6.2 9.4 6.5 6.2 6.2 26 12 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 CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) NOVEMBER 17 69 18 14 9.0 9.3 30 41 11 9.6 7.4 7.2 9.5 6.9 7.8 17 9.5 9.1 8.1 8.3 201 76 32 43 9.9 12 15 8.7 8.9 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 1.6 .90 43 1.5 .73 .75 .52 2.2 1.9 .64 .43 7.4 .73 3.1 .34 28 .35 .29 .26 32 2.0 2.3 1.7 .41 .40 .46 2.4 .51 .58 21 1.9 325.0 845.24 735.1 3274.09 408.1 160.30 180 RIO PUERTO NUBVO BASIN 50049000 RIO PIBDRAS AT RIO PIEDRAS, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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 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 MEAN CONCBN- 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 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) FEBRUARY 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 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 .20 14 .27 .27 .27 .28 .28 .28 .44 —— MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) MARCH 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 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 .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 TOTAL 1076.3 9672.46 255.7 29.79 395.0 2559.49 181 RIO PUERTO NUEVO BASIN 50049000 RIO PIBDRAS AT RIO PIBDRAS, PR—Continued SEDIMEMT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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 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 MEAN CONCBN- 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 MEAN DISCHARGE (CPS) MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) MAY .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—— 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 1030 1000 33 11 10 604 35 23 49 57 38 19 16 IS IS 789 64 553 373 86 314 48 1290 922 148 2050 287 141 365 457 127 2500 1370 1.2 .21 .15 1020 1.2 .59 8.4 4.7 1.8 .43 .32 .30 .34 1570 3.7 850 223 7.9 267 2.1 1800 980 18 6250 62 18 254 170 17 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) JUNE 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 7.3 591 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 4542.59 182 RIO PUERTO NUEVO BASIN 50049000 RIO PIBDRAS AT RIO PIEDRAS, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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 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 DISCHARGE (CPS) MEAN CONCEN- SEDIMENT TRATION DISCHARGE (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 CONCEN- 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--- 505.2 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 --- 3370.50 RIO PUERTO NUEVO BASIN 50049000 RIO PIEDRAS AT RIO PIEDRAS, PR--Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT 183 DATE NOV 1992 18... 30... DEC 14... 26... APR 1993 29... TIME 1345 1405 2138 0050 1937 DIS- CHARGE, INST. CUBIC FEET PER SECOND 2450 1190 2890 602 3240 SEDI- MENT, SUS- PENDED (M6/L) 16000 3520 9510 5520 5080 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 106000 11300 74000 8980 44500 SED. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM 30 37 34 40 32 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM 43 43 45 48 37 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 48 48 50 57 41 DATE NOV 1992 18... 30... DEC 14. .. 25... APR 1993 29... SED. SUSP. FALL DIAM. PERCENT FINER THAN .016 MM 59 56 63 66 46 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM 70 67 74 79 57 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 83 77 84 89 71 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 92 90 92 95 84 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 98 98 98 99 94 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 99 99 99.7 99.8 99 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 100 100 100 100 100 184 RIO PUERTO NUBVO BASIN S0049000 RIO PIEDRAS AT RIO PIBDRAS, PR—Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM DATE NOV 1992 18... 18... 20... DEC 14... 15... 24... 24... 25. .. 26. .. APR 1993 29. .. 30. .. TIME 1445 1715 1320 2008 0008 0930 1245 2350 0505 1852 0037 STREAM- FLOW, INSTAN- TANEOUS (CFS) 3920 438 622 SEDI- MENT, SUS- PENDED (M6/L) 5270 1500 1480 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 55780 1770 2480 1420 1130 291 291 296 304 SIS 573 3220 2860 2460 810 1610 2010 4650 2580 12340 8720 1930 636 1290 1650 6460 3990 74 91 74 60 71 95 99 89 91 57 81 RIO PUERTO NOBVO BASIN 50049100 RIO PIBORAS AT HATO REY, PR LOCATION.—Lat 18°24'34", long 66°04'10", Hydrologic Unit 21010005, at bridge on Avenida Pifieiro at Bxpreso Laa Amtricas, and 0.8 mi (1.3 km) southwest of Hato Rey. 185 DRAINAGE AREA.--15.4 ml 1 (39.9 km1 ). 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. GAGB.—Water-stage recorder and crest-stage gage. Elevation of gage is 16 ft (5 m), from topographic map. REMARKS.—Records fair except those for estimated daily discharges, which are poor. Mean daily discharge affected by sewage discharges (approximately 2.0 ftVs (0.06 m3/*)), 20 ft (6 m) upstream from gaging station. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR HAY JUN JUL AUG SEP 1 18 83 2 16 42 3 16 343 4 44 1680 5 17 153 6 19 150 7 21 110 8 101 102 9 36 114 10 85 93 11 29 76 12 17 175 13 15 130 14 26 85 15 16 123 16 65 93 17 22 199 18 51 699 19 19 154 20 20 e328 21 20 119 22 38 e255 23 85 109 24 65 e!02 25 28 94 26 31 82 27 102 e308 28 30 e605 29 31 e231 30 185 e202 31 50 —— TOTAL 1318 7039 MEAN 42.5 235 MAX 185 1680 MIN 15 42 AC-FT 2610 13960 CFSM 2.80 15.4 IN. 3.23 17.23 100 85 e87 el!7 82 78 67 70 70 71 73 73 78 e902 286 109 104 108 117 99 102 121 123 259 201 565 204 273 323 181 95 5223 168 902 67 10360 11.1 12.78 STATISTICS OF MONTHLY MEAN DATA MEAN 63.7 82.3 MAX 134 235 (WY) 1991 1993 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 61.1 168 1993 18.8 1992 FOR 84 81 100 83 122 126 322 113 91 91 88 107 83 93 79 77 73 71 71 69 69 255 102 79 119 68 60 57 74 61 50 3018 97.4 322 50 5990 6.40 7.39 FOR WATER 51.5 97.4 1993 29.9 1989 47 45 61 40 39 34 33 30 29 29 25 37 25 21 21 20 55 23 22 60 27 22 23 22 24 21 21 19 --- 875 31.2 61 19 1740 2.06 2.14 YEARS 1988 39.0 80.2 1991 10.8 1992 23 21 20 20 21 21 20 18 19 29 20 23 41 28 24 107 44 34 33 32 30 31 48 379 76 48 44 38 37 34 31 1394 45.0 379 18 2760 2.96 3.41 - 1993 35.4 53.8 1990 22.2 1992 1992 CALENDAR YEAR 27647. 75. 1680 6. 7. 54840 4. 67. 196 25 9. 4 5 Nov 4 9 Mar 1 8 Feb 26 97 66 9 e27 e30 e29 e29 e27 e35 e60 ellO e35 e30 e250 e40 ellO e90 e35 e30 e50 e27 e25 elOO e300 e26 19 30 35 29 39 120 685 401 —— 2853 95.1 685 19 5660 6.26 6.98 93 82 164 81 62 78 229 107 94 93 75 59 52 78 45 36 34 29 26 29 32 24 201 133 100 72 393 117 35 23 17 2693 86.9 393 17 5340 5.72 6.59 16 15 15 14 15 14 14 40 62 26 13 18 82 31 82 24 17 20 459 136 28 28 19 26 16 16 16 16 51 16 --- 1345 44.8 459 13 2670 2.95 3.29 12 66 58 16 14 14 264 49 26 24 862 106 43 39 56 24 19 17 24 16 31 267 362 177 29 255 72 23 18 18 19 3020 97.4 862 12 5990 6.41 7.39 21 20 21 18 16 16 15 15 15 15 15 13 12 13 18 40 13 12 12 12 16 17 14 13 14 12 13 16 111 47 22 627 20.2 111 12 1240 1.33 1.53 16 18 16 15 31 338 61 42 25 107 19 15 41 15 20 16 124 30 43 13 43 13 41 13 11 15 27 47 14 26 —— 1255 41.8 338 11 2490 2.75 3.07 , BY WATER YEAR (WY) 57.2 95.1 1993 31.6 1991 FOR 1993 30660 84 1680 11 14 6920 18 60810 5 75 183 39 15 57.4 97.5 1992 30.8 1989 WATER YEAR .0 Nov 4 Sep 25 Aug 17 Apr 29 .89 Apr 29 .53 .04 41.4 78.1 1989 23.0 1991 50.5 97.4 1993 24.8 1990 WATER 54 84 41 1830 6 7 8640 20 39270 3 48 120 23 12 54.7 84.2 1988 20.2 1993 YEARS 1988 - .2 .0 .4 Sep 18 .9 Mar 1 .8 Feb 26 Jun 17 .77 Jun 17 .57 .46 68.8 150 1989 32.6 1991 1993 1993 1990 1989 1992 1992 1970 1970 e Estimated RIO PUERTO NUBVO BASIN 50049100 RIO PIEDRAS AT HATO KEY, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°24'34", long 66°04'10", at bridge on Avenida Pifiero at Bxpreso Las Americas, and 0 (1.3 km) southwest of Hato Rey. DRAINAGE AREA.--15.4 mi' (39.9 km'). PERIOD OF RECORD.—Hater years 1971 to current year. HATER-QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 ,8 mi DATE OCT 1992 01... DEC 15... FEB 1993 16... APR 22... JUN 01... AUG 04... TIME 1235 1210 1220 1150 1545 1125 DIS- CHARGE, INST. CUBIC FEET PER SECOND 18 78 23 29 16 22 SPE- CIFIC CON- DUCT- ANCE (US/CM) 400 410 735 415 500 460 PH HATER WHOLE FIELD (STAND- ARD UNITS) 7.8 6.9 7.6 7.0 7.1 7.8 TEMPER- ATURE HATER (DBG C) 29.5 25.0 26.0 28.0 32.5 26.5 TUR- BID- ITY (NTU) 4.2 11 29 12 3.2 0.20 OXYGEN, DIS- SOLVED (MG/L) 5.6 6.2 6.0 4.0 8.4 11.0 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 73 81 78 52 110 145 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 17 20 180 30 38 17 COLI- FORM, FECAL, 0.45 UM-MP (COLS./ 100 ML) K700000 K600000 600000 560000 K80000 K200000 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 45000 K600000 K100000 52000 3700 K12000 DATE OCT 1992 01. .. DEC 15... FEB 1993 16. .. APR 22... JUN 01. .. AUG 04... HARD- NESS TOTAL (MG/L AS HARD- NESS NONCARB CALCIUM WH HAT TOT FLD DIS- SOLVED CACO3) CAC03 MG/L AS (MG/L MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L AS CA) AS MG) AS NA) 140 0 42 9.0 22 130 1 35 9.4 21 170 0 47 12 29 SODIUM AD- SORP- TION (MG/L RATIO POTAS- SIUM, DIS- SOLVED AS K) 0.8 3.9 0.8 3.5 1 3.4 ALKA- LINITY HAT WH TOT PET SULPIDB FIELD CACO3 140 110 200 120 130 150 TOTAL (MG/L MG/L AS (MG/L SULPATB DIS- SOLVED (MG/L <0.5 25 <0.5 25 23 CHLO- RIDE, DIS- SOLVED (MG/L AS S) AS S04) AS CL) 27 26 29 SOLIDS, RESIDUE DATE OCT 1992 01... DEC 15.. . PBB 1993 16... APR 22... JUN 01.. . AUG 04... PLUO- RIDB, DIS- SOLVED (MG/L AS P) 0.20 -- -- 0.20 -- 0.20 SILICA, DIS- SOLVED (MG/L AS SIO2) 22 — -- 23 -- 27 SUM OP CONSTI- TUENTS, DIS- SOLVED (MG/L) 235 -- -- 215 -- 268 SOLIDS, DIS- SOLVED (TONS PER DAY) 11.4 -- -- 16.8 -- 15.9 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) <1 9 65 1 34 2 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.700 0.800 0.790 1.21 0.590 0.520 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.070 0.100 0.010 0.090 0.010 0.080 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 0.770 0.900 0.800 1.22 0.600 0.600 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 1.30 0.590 0.020 1.10 1.10 1.50 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 1.1 1.3 0.48 1.1 1.5 1.4 non-ideal count DATE OCT 1992 01... DEC 15... FBB 1993 16... APR 22... JUN 01.. . AUG 04... DATE OCT 1992 01.. . DEC 15.. . FEB 1993 16.. . APR 22... JUN 01.. . AUG 04... RIO PUERTO NDEVO BASIN 50049100 RIO PIEDRAS AT HATO REY, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 187 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 2.4 1.9 0.50 2.2 2.6 2.9 IRON, TOTAL RECOV- ERABLE (UG/L AS PE) NITRO- GEN, TOTAL (MG/L AS N) 3.2 3.1 0.30 1.2 0.90 0.80 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS NO3) 14 9.2 5.8 16 15 9 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.420 0.380 0.020 0.160 0.230 0.210 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) ARSENIC TOTAL (UG/L AS AS) 2 -- -- 2 -- -- SELE- NIUM, TOTAL (UG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) 200 -- - 200 -- -- SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) 40 -- -- 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 -- -- 4 -- -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CO) <10 - — 20 - -- MBTHY- LBNB BLUB ACTIVE SUB- STANCE (MG/L) 760 2400 140 260 <0.10 <0.10 20 20 <0.010 <0.010 0.33 0.19 188 RIO PUERTO NUBVO BASIN 50049820 LACUNA SAN JOSE NO. 2 AT SAN JUAN, PR WATER-QUALITY RECORDS LOCATION.--Lat 16°25'46", long 66°02'10", 0.2 ml (0.3 km) east of Ca-o de Martin Pe-a, 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 1992 TO SEPTEMBER 1993 DATE NOV 1992 05... JAN 1993 05... MAR 08... MAY 04... JUN 21... AUG 24... DATE NOV 1992 05... JAN 1993 05... MAR 08... MAY 04... JUN 21... AUG 24... TIME 0800 0820 1000 0930 1025 1045 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 6 28 <1 13 15 4 SPE- CIFIC CON- DUCT- ANCE (US/CM) 13200 32000 21000 12800 14000 22500 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.090 -- -- -- 0.070 -- WATER WHOLE FIELD (STAND- ARD UNITS) 7.6 7.5 7.2 7.5 7.7 7.1 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.010 <0.010 <0.010 <0.010 0.030 <0.010 PH TEMPER- ATURE WATER (DBG C) 26.0 28.5 25.2 27.5 27.6 30.5 NITRO- GEN, N02+N03 TOTAL (MG/L AS N) 0.100 0.100 0.100 0.100 0.100 0.100 TRANS- PAR- ENCY (SECCHI DISK) (IN) 18 19.9 36 28 26 37 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.220 0.120 1.20 0.050 0.110 0.050 OXYGEN, DIS- SOLVED (MG/L) 4.8 3.7 5.0 4.7 6.1 2.0 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 2.2 2.4 2.5 2.4 1.8 1.7 DIS- SOLVED (PER- CENT SATUR- ATION) 58 48 59 58 76 24 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 2.4 2.5 3.7 2.4 1.7 1.8 OXYGEN, FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 4700 32000 3900 K12000 K10000 K18000 NITRO- GEN, TOTAL (MG/L AS N) 2.5 2.6 3.8 2.5 1.8 1.9 COLI- STRBP- TOCOCCI FECAL, (COLS. PER 100 ML) R6000 7100 K200 K730 -- K90000 PHOS- CARBON, PHORUS ORGANIC TOTAL TOTAL (MG/L (MG/L AS P) AS C) 0.57 16 0.53 18 0.70 13 0.31 11 0.26 13 0.40 16 K = non-ideal count 189 RIO PUERTO NUBVO BASIN 50049920 BAHIA DE SAN JOAN NO. 5 AT SAN JOAN, PR WATER-QUALITY RECORDS LOCATION—Lat 18°26'37", long 66°05'11", 0.4 ml (0.6 km) west of Puente de la Constituci[n, and 0.5 ml (0.8 km) south from O.S. Naval Reservation. DRAINAGE—Indeterminate. PERIOD OF RECORD—Water years 1974 to present. WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE NOV 1992 05... JAN 1993 05... MAR 08... MAY 04. .. JUN 21... AUG 24. .. DATE NOV 1992 05... JAN 1993 05... MAR 08... MAY 04. .. JUN 21. .. AUG 24... TIME 0915 0930 1055 1030 1110 1150 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 5 12 15 70 17 19 SPE- CIFIC CON- DUCT- ANCE (US/CM) 11700 43000 42100 25400 30000 >50000 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.060 0.090 0.090 0.070 0.230 0.160 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.1 7.3 7.6 7.2 6.9 7.9 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.040 0.010 0.010 0.030 0.070 0.040 TEMPER- ATURE WATER (DBG C) 26.0 24.6 26.0 28.0 28.4 29.4 4 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 0.100 0.100 0.100 0.100 0.300 0.200 TRANS- PAR- ENCY (SBCCHI DISK) (IN) 7 14 30 7 24 16 * NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.900 0.640 1.20 1.70 2.20 0.78 OXYGEN, DIS- SOLVED (MG/L) 1.5 1.8 4.0 1.4 0.2 1.6 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 1.0 0.06 2.0 1.5 0.60 0.32 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 18 21 48 18 2 20 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.90 0.70 3.2 3.2 2.8 1.1 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) R6000 320000 360000 46000 160000 58000 NITRO- GEN, TOTAL (MG/L AS N) 2.0 0.80 3.3 3.4 3.1 1.3 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) R6000 230000 30000 35000 180000 K120000 NITRO- GEN, TOTAL (MG/L AS NO3) 1.9 — — — 14 5.8 ALKA- LINITY WAT WH TOT FET FIELD MG/L AS CAC03 140 150 120 130 120 120 PHOS- CARBON, PHORUS ORGANIC TOTAL TOTAL (MG/L (MG/L AS P) AS C) 0.280 4.8 0.080 2.4 0.300 5.2 0.310 3.1 0.410 2.0 0.140 4.7 K - non-ideal count 190 THIS PAGE WAS LEFT BLANK INTENTIONALLY 191 ATLANTIC OCEAN "yi ,-**Q X.r*t>& / J \ ft:cs Estp.V.hi \ f \ Senio tfo*:n U /-^S / 0^1755225 0123456 KILOMETERS ! I 01234 MiLES SURFACE-WATER STATION 0509 AND NUMBER V 0554 QUALITY-OF-WATER STATION AND NUMBER V7 rw7«5 QUALITY-OF-WATER V «>« PARTIAL RECORD STATION AND NUMBER • ^ WELL AND WELL NUMBER • 0590 LAKE-ELEVATION STATION Figure 20.-Rio Grande de Loiza basin. 192 RIO GRANDB DE LOIZA BASIN 50050300 QUBBRADA BLASINA NEAR CAROLINA, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°23'27", long 65°58'28", at bridge on Highway 3, 1.4 mi (2.3 km) south of Valle Arriba Heights housing area, and 1.2 mi (1.9 km) weet-Bouthweet of Carolina plaza. DRAINAGE AREA.--2.96 mi* (7.67 km*). PERIOD OF RECORD.--Hater yearn 1973 to current year. WATER-QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 21... DEC 16... PBB 1993 16... APR 15... JUN 08. .. AUG 09. .. TIME 1205 0900 0915 1410 1200 1350 DIS- CHARGE, INST. CUBIC FEET PER SECOND 8.4 6.3 7.9 4.7 8.4 5.S SPE- CIFIC CON- DUCT- ANCE (US/CM) 404 418 494 558 557 441 PH HATER WHOLE FIELD (STAND- ARD UNITS) 7.5 7.5 7.2 7.3 7.6 7.3 TEMPER- ATURE HATER (DBG C) 28.0 23.9 23.5 2S.5 27.0 29.0 TUR- BID- ITY (NTU) 8.2 32 220 3.3 7SO 54 OXYGEN, DIS- SOLVED (MG/L) 5.3 6.5 4.4 3.2 5.2 5.9 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 66 87 58 41 68 79 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) <10 <10 170 20 300 24 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K100000 380000 600000 K19000 530000 20000 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) K24000 53000 250000 24000 950000 K2900 DATE OCT 1992 21... DEC 16... FEB 1993 16... APR 15... JUN 08... AUG 09. .. HARD- NESS TOTAL (MG/L AS HARD- NESS NONCARB HH HAT 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 CACO3) CACO3 AS CA) AS MG) AS NA) 170 13 50 8.7 32 180 6 54 11 33 160 11 49 8.0 29 ALKA- POTAS- LINITY CHLO- SIUM, HAT HH SULFATB RIDE, DIS- TOT FBT SULFIDE DIS- DIS- SOLVED FIELD TOTAL SOLVED SOLVED (MG/L MG/L AS (MG/L (MG/L (MG/L AS K) 4.9 3.1 0.8 4.5 CAC03 160 130 220 170 150 130 AS S) AS SO4) AS CL) <O.S 26 <0.5 23 34 30 40 33 SOLIDS, RESIDUE DATE OCT 1992 21... DEC 16... FBB 1993 16... APR 15.. . JUN 08... AUG 09... FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.40 -- -- 0.20 -- 0.10 SILICA, DIS- SOLVED (MG/L AS SI02) 21 -- -- 25 -- 22 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 39S -- -- 291 -- 253 SOLIDS, DIS- SOLVED (TONS PER DAY) 9.02 — — 3.70 — 3.96 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) <10 41 592 32 6010 46 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.760 0.330 0.370 0.450 0.600 0.260 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.120 0.070 0.030 0.050 0.100 0.040 NITRO- GEN, N02+N03 TOTAL (MG/L AS N) 0.880 0.400 0.400 0.500 0.700 0.300 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.430 0.140 0.070 0.140 0.410 0.130 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 1.3 0.36 0.33 0.46 0.59 0.37 non-ideal count DATE OCT 1992 21... DEC 16... FBB 1993 16... APR 15.. . JUN 08... AUG 09... DATE OCT 1992 21... DEC 16... FBB 1993 16... APR 15... JUN 08... AUG 09... RIO GRANDB DE LOIZA BASIN 50050300 QOEBRADA BLASINA NEAR CAROLINA, PR--Continued HATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 193 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 1.7 0.50 0.40 0.60 1.0 0.50 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) 2.6 0.90 0.80 1.1 1.7 0.80 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS NO3) 11 4.0 3.5 4.9 7.5 3.5 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.660 0.200 5.20 0.410 0.070 0.180 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) 200 - -- <100 -- -- SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) 40 -- -- 70 -- -- ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) 2 -- -- <1 — -- CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) 13 -- -- <1 -- -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) <10 -- — <10 — -- MBTHY- LENE BLUB ACTIVE SUB- STANCE (MG/L) 2000 310 16 750 250 <0.10 <0.10 11 <0.010 •cO.010 0.05 0.24 194 RIO GRANDE DE LOIZA BASIN 50050900 RIO GRANDE DB LOIZA AT QUEBRADA 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 9 (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 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 elO e!2 2 e9.2 e9.7 3 e9.0 elO 4 e8.4 e61 5 elO e!9 6 e!4 e58 7 e9.0 e33 8 e8.8 e!6 9 e8.5 e!2 10 e8.3 ell 11 e8.9 e9.9 12 e8.4 e9.6 13 e7.6 e9.2 14 e7.8 e8.5 15 e7.4 e!3 16 e7.5 elO 17 e8.1 e25 18 e9.4 e81 19 e7.6 e44 20 e26 e42 21 e23 el7 22 el7 e32 23 ell e!7 24 e9.8 e54 25 e60 e!6 26 e71 e!3 27 e!4 e38 28 ell e!21 29 e22 e33 30 e!6 e55 31 e!6 —— TOTAL 464.7 889.9 MEAN 15.0 29.7 MAX 71 121 MIN 7.4 8.5 AC-FT 922 1770 CFSM 2.50 4.94 IN. 2.88 5.52 STATISTICS OF MONTHLY MEAN MEAN 41.8 47.3 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 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS e37 e22 e90 e30 e21 e22 el9 el8 el7 el6 elS elS e!6 e!7 e!8 elS elS el4 e!4 el4 elS e!6 el4 e!5 e22 e34 e21 e!6 e30 e25 e30 683 22.0 90 14 1350 3.67 4.23 DATA 24.5 55.2 1988 6.65 1990 FOR e40 e25 e22 e21 e!7 e24 e27 e23 e21 e20 e!8 e!8 e!7 e!8 e!6 elS elS e!4 e!6 e!3 e!3 e23 e!5 e27 e20 e!8 e27 e54 e28 e!7 elS 657 21.2 54 13 1300 3.53 4.07 FOR WATER 18.5 56.1 1992 8.16 1990 elS e!8 elS e!3 e!3 el3 e!2 el2 ell e!2 e!4 e!7 e!4 e!2 ell ell ell elO ell ell elO elO elO elO e9.0 e9.0 e9.2 e9.2 —— 332.4 11.9 18 9.0 659 1.98 2.06 YEARS 1978 16.5 38.0 1982 6.36 1979 e9.4 e8.4 e7.9 e7.5 e7.5 e7.4 e7.5 e7.2 e7.2 e7.0 e7.0 e7.4 e7.8 e7.6 e7.8 e7.2 e8.2 e8.6 elO e9.4 e8.0 e7.0 e6.8 6.9 8.2 9.6 7.6 6.7 6.3 6.0 5.8 236.9 7.64 10 5.8 470 1.27 1.47 - 1993 12.4 33.1 1989 5.07 1979 1992 CALENDAR YEAR 9358. 25. 1000 5. 5. 18560 4. 58. 44 14 6. 5 6 Jan 5 0 Apr 28 4 Apr 25 26 02 6 6.4 6.2 6.0 5.8 5.8 5.7 5.2 6.4 8.3 6.4 5.2 5.1 13 10 6.3 19 30 7.1 6.6 18 9.1 6.5 33 8.4 6.8 6.5 9.1 5.9 185 30—— 482.8 16.1 185 5.1 958 2.68 2.99 202 178 49 24 60 27 15 17 107 32 18 14 12 299 40 24 19 17 15 15 14 14 14 12 16 13 12 11 10 9.8 9.5 1319.3 42.6 299 9.5 2620 7.09 8.18 12 11 9.8 9.1 8.7 8.3 8.0 8.7 8.0 19 11 9.0 15 98 137 40 18 248 498 155 41 205 46 35 24 20 17 15 18 32—— 1784.6 59.5 498 8.0 3540 9.91 11.06 15 16 32 17 13 11 32 25 14 12 e946 e!20 62 50 43 192 47 38 46 59 53 235 215 215 85 69 53 43 38 34 32 2862 92.3 946 11 5680 15.4 17.74 30 27 24 22 21 20 19 19 18 20 37 20 18 17 22 302 54 30 25 22 20 70 139 70 33 27 23 23 20 19 32 1243 40.1 302 17 2470 6.68 7.71 23 28 28 18 17 15 15 25 24 63 26 18 17 15 14 48 18 57 17 40 16 18 335 40 20 16 15 19 153 110 1268 42.3 335 14 2520 7.04 7.86 , BY WATER YEAR (WY) 13.3 27.1 1985 4.64 1979 FOR 1993 12223 33 946 5 5 7260 12 4 24250 5 75 58 16 7 34.7 77.5 1985 9.56 1988 WATER YEAR .6 .5 Jul 11 .1 Apr 12 . 9 Apr 1 Jul 11 .40 Jul 11 . 9 Apr 7 .58 .79 .5 39.3 122 1979 11.3 1985 38.2 92.3 1993 12.5 1986 WATER 29 49 14 1250 3 3 11700 14 2 21340 4 66 50 15 6 30.5 90.0 1979 9.30 1991 YEARS 1978 .5 .6 .5 Oct .1 May .6 May Nov .78 Nov .8 May .91 .71 .9 36.1 94.3 1979 11.8 1981 - 1993 1979 1990 6 1985 7 1979 1 1979 5 1983 5 1983 5 1979 e Estimated RIO GRANDE DE LOIZA BASIN 195 50051150 QUEBRADA BLANCA AT EL JAGUAL, 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 Lorenzo. DRAINAGE AREA.--3.25 mi' (8.42 km'). WATER-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 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 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JDN JUL AUG SEP 1 2.5 1.6 2 2.4 1.6 3 2.4 1.9 4 2.0 6.7 5 1.7 3.0 6 14 8.0 7 7.6 7.0 8 4.0 3.3 9 3.3 2.6 10 2.7 3.1 11 2.3 2.2 12 1.9 2.0 13 1.7 1.9 14 1.8 1.8 15 1.7 7.4 16 1.8 3.7 17 1.9 3.7 18 1.9 14 19 1.9 10 20 2.3 6.7 21 1.9 5.5 22 1.7 4.8 23 2.0 3.5 24 3.0 2.9 25 3.2 2.4 26 3.0 2.2 27 2.0 11 28 1.8 34 29 1.7 10 30 1.7 24 31 1.6 TOTAL 85.4 192.5 MEAN 2.75 6.42 MAX 14 34 MIN 1.6 1.6 AC-FT 169 382 CFSM .85 1.97 IN. .98 2.20 STATISTICS OF MONTHLY MEAN MEAN 11.8 18.2 MAX 47.8 36.9 (WY) 1986 1985 MIN 2.75 2.49 (WY) 1993 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 20 15 11 8.7 7.2 6.0 5.1 4.5 4.1 3.8 3.6 3.4 3.4 5.8 5.3 3.6 3.3 3.2 3.1 3.2 3.0 5.3 3.6 3.4 5.1 20 7.9 5.1 9.6 6.4 13 205.7 6.64 20 3.0 408 2.04 2.35 DATA 7.76 30.1 1988 1.49 1990 FOR 20 11 9.2 7.8 5.8 5.0 7.7 5.8 7.6 5.1 4.1 3.8 3.4 7.0 4.0 3.8 3.7 3.3 3.5 3.4 3.3 3.6 3.9 3.7 4.2 4.0 5.4 6.5 11 5.9 4.9 181.4 5.85 20 3.3 360 1.80 2.08 4.5 6.3 5.0 4.4 4.3 4.2 4.2 4.0 3.9 3.9 4.4 4.9 5.2 4.1 3.7 3.5 3.4 3.4 3.3 3.3 3.1 2.9 2.4 2.4 2.0 2.0 2.2 1.9 ___ --- 102.8 3.67 6.3 1.9 204 1.13 1.18 FOR WATER YEARS 1984 4.94 9.94 1992 1.79 1990 4.00 8.21 1989 1.32 1985 1.6 1.6 1.9 1.8 1.8 1.8 1.7 1.6 1.6 1.8 1.7 1.7 1.9 1.8 2.1 1.8 2.4 2.1 2.4 1.9 1.7 1.4 1.3 1.3 1.4 1.4 1.3 1.1 1.0 .99 1.0 50.89 1.64 2.4 .99 101 .51 .58 - 1993 4.31 20.7 1989 1.64 1993 1992 CALENDAR YEAR 2121.88 5.80 194 .72 1.1 4210 1.78 24.29 11 2.7 1.4 Jan 5 Jan 4 Mar 24 1.1 1.1 1.2 1.1 1.1 1.1 1.1 1.9 1.9 1.5 1.3 1.3 1.7 2.1 1.5 1.6 1.3 1.1 1.3 1.3 1.4 1.1 1.1 1.1 1.0 1.3 2.3 1.5 6.8 10 55.2 1.84 10 1.0 109 .57 .63 , BY WATER 2.45 4.88 1989 .90 1991 12 16 8.4 3.5 3.3 2.4 1.9 2.0 8.4 4.7 3.4 2.4 1.9 19 9.3 4.4 2.9 2.2 1.7 1.7 1.5 1.3 1.4 1.3 1.7 6.8 8.4 5.3 3.5 2.9 2.6 148.2 4.78 19 1.3 294 1.47 1.70 YEAR (WY) 8.90 31.5 1985 1.51 1990 3.0 2.6 2.2 1.9 1.7 1.6 1.5 1.6 2.6 4.7 2.8 2.1 2.5 17 11 5.0 2.2 13 48 26 11 10 6.3 6.0 3.7 2.8 2.2 1.9 2.1 2.7 —— 201.7 6.72 48 1.5 400 2.07 2.31 6.26 21.3 1987 2.40 1991 FOR 1993 HATER YEAR 2010.39 5.51 213 .99 1.1 3730 11.20 3990 1.69 23.01 10 3.2 1.5 Jul 11 Mar 30 Mar 28 Jul 11 Jul 11 1.9 2.1 6.0 2.7 1.9 1.6 1.7 3.3 1.7 1.6 e213 e!8 10 6.7 5.3 7.5 4.7 4.2 4.0 3.9 3.4 36 32 22 12 17 16 8.5 6.5 5.2 4.7 465.1 15.0 213 1.6 923 4.62 5.32 6.14 15.0 1993 2.02 1986 HATER 7. 12. 2. 457 . . 7400 14. 5360 2. 30. 12 2. 1. 4.1 3.5 3.0 2.9 2.9 2.7 2.4 2.9 3.0 3.9 3.4 3.5 3.2 2.8 4.7 78 16 9.3 7.1 5.7 4.9 4.9 9.1 4.8 4.2 3.7 3.2 2.8 2.6 2.5 3.8 211.5 6.82 78 2.4 420 2.10 2.42 6.48 20.2 1988 2.21 1985 YEARS 1984 - 39 3 50 Dec 7 38 Aug 10 42 Aug 7 May 17 58 May 17 27 90 6 1 3.2 2.7 3.1 2.6 3.3 2.4 2.3 2.9 3.2 11 5.0 3.3 2.9 2.8 2.7 6.3 3.3 5.3 3.2 3.0 2.4 2.1 8.2 4.7 2.8 2.3 1.9 2.0 3.2 5.9 --- 110.0 3.67 11 1.9 218 1.13 1.26 7.23 14.3 1985 1.36 1990 1993 1988 1990 1987 1991 1991 1985 1985 e Estimated 196 RIO GRANDB DE LOIZA BASIN 50051150 QDEBRADA BLANCA AT EL JAGUAL, PR--Continued WATBR-QOALITY 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 1993. INSTRUMENTATION.-- EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATION: 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 YEAR 1993.-- SBDIMENT CONCENTRATION: Maximum daily mean, 1,150 mg/L Nov. 08, 1991; Minimum daily mean, 1 mg/L several days. SEDIMENT LOADS: Maximum daily mean, e2,860 tons (e2,580 tonnes) July 11, 1993; Minimum daily mean, <.01 ton several days. SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 MEAN MEAN MEAN CONCBN- SEDIMENT MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DAY (CFS) (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 2.5 2.4 2.4 2.0 1.7 14 7.6 4.0 3.3 2.7 2.3 1.9 1.7 1.8 1.7 1.8 1.9 1.9 1.9 2.3 1.9 1.7 2.0 3.0 3.2 3.0 2.0 1.8 1.7 1.7 1.6 3 3 3 18 3 100 13 2 1 1 2 2 3 3 3 4 3 2 1 1 1 2 4 6 4 4 3 3 3 2 3 .02 .02 .02 .12 .02 16 .36 .02 .01 .01 .02 .01 .01 .01 .01 .02 .02 .02 .01 .00 .00 .01 .02 .06 .03 .04 .02 .02 .02 .01 .01 NOVEMBER 1.6 1.6 1.9 6.7 3.0 8.0 7.0 3.3 2.6 3.1 2.2 2.0 1.9 1.8 7.4 3.7 3.7 14 10 6.7 5.5 4.8 3.5 2.9 2.4 2.2 11 34 10 24 ___ 5 8 9 18 7 29 20 5 4 3 3 3 3 4 37 8 13 85 34 15 8 7 7 5 2 2 67 566 38 107 .03 .04 .05 .42 .07 1.4 .63 .05 .03 .03 .02 .02 .02 .02 2.1 .09 .16 8.6 1.2 .34 .13 .10 .07 .04 .02 .02 6.1 131 2.9 12 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) DECEMBER 20 15 11 8.7 7.2 6.0 5.1 4.5 4.1 3.8 3.6 3.4 3.4 5.8 5.3 3.6 3.3 3.2 3.1 3.2 3.0 5.3 3.6 3.4 5.1 20 7.9 5.1 9.6 6.4 13 134 22 12 13 11 9 6 5 5 5 4 3 2 16 19 3 2 3 3 3 3 17 23 15 12 73 25 11 31 15 54 14 .96 .34 .29 .22 .15 .09 .06 .06 .05 .04 .03 .02 .73 .36 .03 .01 .02 .02 .02 .02 .30 .24 .14 .18 7.3 .60 .16 1.1 .25 4.0 TOTAL 85.4 16.97 192.5 167.70 205.7 31.79 797 RIO GRANDS DB LOIZA BASIN 50051150 QOBBRADA BLANCA AT EL JAOUAL, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (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 TOTAL 20 11 9.2 7.8 5.8 5.0 7.7 5.8 7.6 5.1 4.1 3.8 3.4 7.0 4.0 3.8 3.7 3.3 3.5 3.4 3.3 3.6 3.9 3.7 4.2 4.0 5.4 6.5 11 5.9 4.9 181.4 66 7 6 7 13 17 30 24 23 8 4 3 3 19 7 5 5 5 5 5 5 4 2 1 1 3 6 9 42 16 10 5.8 .21 .15 .15 .20 .23 .92 .44 .66 .12 .06 .03 .02 .61 .08 .05 .05 .04 .05 .05 .04 .04 .03 .02 .02 .03 .09 .15 2.0 .27 .14 12.75 FEBRUARY 4.5 6.3 5.0 4.4 4.3 4.2 4.2 4.0 3.9 3.9 4.4 4.9 5.2 4.1 3.7 3.5 3.4 3.4 3.3 3.3 3.1 2.9 2.4 2.4 2.0 2.0 2.2 1.9 102.8 7 15 8 5 5 7 8 9 7 5 6 8 7 7 6 5 4 6 7 7 5 5 6 8 9 8 8 7 .09 .39 .12 .06 .06 .08 .10 .10 .08 .06 .08 .11 .10 .07 .06 .05 .04 .05 .07 .07 .05 .04 .04 .05 .05 .04 .04 .04 2.19 MEAN DISCHARGE (CFS) 1.6 1.6 1.9 1.8 1.8 1.8 1.7 1.6 1.6 1.8 1.7 1.7 1.9 1.8 2.1 1.8 2.4 2.1 2.4 1.9 1.7 1.4 1.3 1.3 1.4 1.4 1.3 1.1 1.0 .99 1.0 MEAN CONCEN- TRATION (MG/L) MARCH 7 7 7 5 5 5 7 9 12 13 11 6 3 2 2 1 1 2 4 4 5 4 4 4 5 5 3 2 2 2 2 SEDIMENT DISCHARGE (TONS/DAY) .04 .04 .04 .02 .02 .02 .03 .04 .05 .06 .05 .03 .02 .01 .01 •e.Ol •e.Ol .01 .02 .02 .02 .02 .02 .02 .02 .02 .01 <.01 •c.Ol •c.Ol •c.Ol 50.89 0.66 198 RIO QRANDB DB LOIZA BASIN 50051150 QOEBRADA BLANCA AT EL JAGUAL, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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 (CFS) (MQ/L) (TONS/DAY) 1.1 1.1 1.2 1.1 1.1 1.1 1.1 1.9 1.9 1.5 1.3 1.3 1.7 2.1 1.5 1.6 1.3 1.1 1.3 1.3 1.4 1.1 1.1 1.1 1.0 1.3 2.3 1.5 6.8 10 APRIL 1 1 1 1 3 3 3 3 3 3 4 5 4 2 2 2 3 3 3 2 2 3 3 4 5 6 3 2 27 45 •c.Ol •c.Ol •c.Ol •c.01 .01 .01 .01 .01 .02 .02 .02 .02 .02 .01 •c.Ol .01 .02 .01 .01 .01 •c.Ol •c.Ol .01 .02 .02 .03 .02 •c.Ol 1.3 2.6 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MAY 12 16 8.4 3.5 3.3 2.4 1.9 2.0 8.4 4.7 3.4 2.4 1.9 19 9.3 4.4 2.9 2.2 1.7 1.7 1.5 1.3 1.4 1.3 1.7 6.8 8.4 5.3 3.5 2.9 2.6 48 84 20 10 6 4 2 3 21 8 3 2 2 133 28 10 5 2 2 2 2 3 4 5 5 26 28 15 8 6 4 2.3 7.5 .55 .10 .05 .03 .01 .01 .57 .12 .03 .02 .02 15 .86 .13 .04 .01 •e.Ol •e.Ol .01 .02 .02 .02 .03 1.1 1.1 .27 .07 .05 .03 MEAN DISCHARGE (CFS) 3.0 2.6 2.2 1.9 1.7 1.6 1.5 1.6 2.6 4.7 2.8 2.1 2.5 17 11 5.0 2.2 13 48 26 11 10 6.3 6.0 3.7 2.8 2.2 1.9 2.1 2.7 MEAN CONCEN- TRATION (MQ/L) JUNE 4 5 5 6 10 4 2 3 100 38 12 8 91 314 126 23 10 8 8 6 3 3 3 5 4 SEDIMENT DISCHARGE (TONS/DAY) .04 .04 .04 .02 .02 .02 .02 .02 .06 .16 .04 .02 .02 11 1.5 .19 .06 84 43 12 .81 .24 .15 .12 .07 .03 .02 .02 .03 .04 TOTAL 55.2 4.21 148.2 30.07 201.7 153.80 RIO GRANDE DB LOIZA BASIN 199 50051150 QUEBRADA BLANCA AT EL JAGDAL, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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 (CFS) (MG/L) (TONS/DAY) 1.9 2.1 6.0 2.7 1.9 1.6 1.7 3.3 1.7 1.6 e213 e!8 10 6.7 5.3 7.5 4.7 4.2 4.0 3.9 3.4 36 32 22 12 17 16 8.5 6.5 5.2 4.7 JULY 2 2 15 8 10 6 2 6 2 2 1150 68 10 8 8 16 8 8 7 6 6 188 185 102 28 60 67 12 8 6 6 TOTAL 465.1 YEAR e 2010.39 Estimated MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AUGUST .01 .01 .37 .06 .05 .03 .02 .08 .01 <.01 e2860 e5.3 .28 .15 .12 .43 .11 .10 .08 .07 .06 131 30 10 .96 7.0 5.0 .27 .14 .09 .08 3051.88 3773.90 4.1 3.5 3.0 2.9 2.9 2.7 2.4 2.9 3.0 3.9 3.4 3.5 3.2 2.8 4.7 78 16 9.3 7.1 5.7 4.9 4.9 9.1 4.8 4.2 3.7 3.2 2.8 2.6 2.5 3.8 211.5 5 5 10 12 10 5 2 7 8 7 8 7 7 6 13 812 46 7 3 3 8 8 18 3 3 3 5 9 10 10 10 ... .05 .04 .07 .09 .08 .04 .02 .06 .07 .07 .07 .07 .06 .05 .36 289 2.4 .19 .06 .05 .10 .10 .60 .05 .04 .03 .04 .06 .06 .07 .10 294.15 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) SEPTEMBER 3.2 2.7 3.1 2.6 3.3 2.4 2.3 2.9 3.2 11 5.0 3.3 2.9 2.8 2.7 6.3 3.3 5.3 3.2 3.0 2.4 2.1 8.2 4.7 2.8 2.3 1.9 2.0 3.2 5.9 110.0 7 2 2 2 3 2 2 3 6 37 10 7 11 12 12 17 6 14 6 2 2 2 39 20 15 10 5 2 5 13 ... .06 .02 .02 .02 .02 .02 .02 .03 .05 1.4 .16 .06 .08 .08 .10 .43 .06 .44 .06 .01 .02 .02 3.7 .29 .12 .06 .02 .01 .06 .29 7.73 200 RIO GRANDE DE LOIZA BASIN 50051150 QUEBRADA BLANCA AT EL JAGUAL, PR--Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 PARTICLE-SIZE DISTRIBUTION OP SUSPENDED SEDIMENT DATE NOV 1992 28. .. TIME 0850 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 SED. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM SED. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 211 5460 3110 29 39 47 SED. SUSP. PALL DIAM. SED. SUSP. FALL DIAM. SED. SUSP. SIEVE DIAM. SED. SUSP. SIEVE DIAM. SED. SUSP. SIEVE DIAM. SED. SUSP. SIEVE DIAM. PERCENT PERCENT PERCENT PERCENT PERCENT PERCENT FINER FINER FINER FINER FINER FINER DATE NOV 1992 28... THAN THAN THAN THAN THAN THAN SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .016 MM .031 MM .062 MM .125 MM .250 MM .500 MM 1.00 MM 60 72 83 92 98 99 100 RIO GRANDE DE LOIZA BASIN 50051150 QOEBRADA BLANCA AT EL JAGUAL--Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT 201 DATE NOV 1992 28.. . MAY 1993 14... JUL 11... 11... AUG 16.. . TIME 0820 1100 0810 1035 0720 STREAM- FLOW, INSTAN- TANEOUS (CFS) 183 50 189 86 145 SEDI- MENT, SUS- PENDED (MG/L) 1790 485 1670 3820 3120 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 884 65 852 887 1220 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 85 87 85 80 97 202 RIO GRANDB DE LOIZA BASIN 50051180 QUBBRADA SALVATIBRRA NEAR SAN LORENZO, PR LOCATION.--Lat 18«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 Loiza, and 1.5 mi (2.4 km) southwest of San Lorenzo. DRAINAGE AREA.--3.74 mi' (9.69 km'). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—January 1984 to current year. GAGE.—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. DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEE MAR APR MAY JUN JUL AUG SEP 1 6.5 2.0 2 5.6 1.7 3 5.4 2.0 4 5.1 7.7 5 5.5 3.4 6 39 7.0 7 5.8 8.1 8 2.6 3.2 9 2.2 2.4 10 2.1 5.9 11 2.5 3.3 12 2.0 1.7 13 1.7 1.7 14 1.6 1.6 15 1.6 3.3 16 1.6 2.2 17 1.6 1.5 18 1.6 26 19 1.9 14 20 4.0 4.5 21 1.8 19 22 1.3 13 23 1.5 4.7 24 2.0 2.1 25 3.2 1.3 26 2.8 1.1 27 2.1 26 28 1.8 124 29 1.8 29 30 1.9 115 31 2.2 TOTAL 122.3 438.4 MEAN 3 . 95 14 . 6 MAX 39 124 MIN 1.3 1.1 AC-FT 243 870 CFSM 1.05 3.91 IN. 1.22 4.36 23 13 6.6 5.8 4.2 3.0 2.7 2.8 2.5 e2.5 e2.4 e2.3 e3.8 e3.5 e2.5 e2.2 e2.1 e2.1 e2.1 e2.1 e3.5 e2.5 e2.3 elO e7.0 eS.O e3.5 e6.8 e4.5 e!3 el7 166.3 5.36 23 2.1 330 1.43 1.65 STATISTICS OF MONTHLY MEAN DATA MEAN 10.3 15.0 MAX 36.2 33.4 (HY) 1986 1988 MIN 2.31 2.72 (HY) 1987 1990 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOHBST ANNUAL MEAN HIGHEST DAILY MEAN LOHBST 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 5.88 22.8 1988 1.17 1990 FOR ell e9.0 e7.0 5.9 5.8 5.5 5.7 4.9 5.2 4.7 4.4 4.1 3.9 5.3 3.7 3.9 3.9 3.4 3.4 3.4 3.2 3.2 3.4 3.0 2.8 2.8 3.4 3.4 4.9 3.3 2.8 140.3 4.53 11 2.8 278 1.21 1.40 2.7 3.4 3.3 2.7 2.7 2.7 2.7 2.5 2.5 2.5 2.5 e2.9 e3.1 e3.3 e2.7 e2.4 e2.3 e2.2 e2.2 e2.2 e2.1 e2.0 el. 9 el. 7 el. 5 el. 4 el. 3 el. 4 ___ --- 66.8 2.39 3.4 1.3 132 .64 .66 FOR HATER YEARS 1984 5.28 23.4 1992 1.16 1990 3.45 10.3 1984 1.23 1990 el. 5 el. 6 el. 2 el. 2 el. 3 el. 2 el. 2 el. 2 el.l el.l 1.2 1.2 1.2 1.0 1.0 1.0 1.9 1.6 1.9 1.8 1.6 1.3 1.3 1.3 1.2 1.2 1.1 .99 .92 .86 .86 39.03 1.26 1.9 .86 77 .34 .39 - 1993 3.49 17.4 1989 1.15 1992 1992 CALENDAR YEAR 2607.15 7.12 472 .84 .98 5170 1.90 25.93 9.0 1.8 1.1 Jan 5 Apr 21 Mar 28 .86 .86 1.1 1.0 .87 .86 .76 .96 1.7 1.3 .98 1.0 1.4 1.8 1.8 2.1 1.4 1.2 1.5 .98 1.0 .98 .91 .78 .74 1.1 4.0 1.7 3.0 el2 50.64 1.69 12 .74 100 .45 .50 , BY HATER 2.69 6.60 1985 .88 1984 el7 eS.O 11 4.3 3.6 3.2 1.8 1.6 7.6 5.6 2.5 1.9 1.9 33 13 5.9 3.7 2.7 2.2 2.2 2.2 1.9 1.8 1.9 1.9 2.2 6.7 5.0 2.2 1.9 1.8 162.2 5.23 33 1.6 322 1.40 1.61 YEAR (HY) 8.25 35.8 1985 1.53 1990 1.7 1.6 1.3 1.1 .98 .93 .91 .86 1.5 3.0 1.6 1.3 1.3 20 17 8.2 3.2 16 124 43 10 12 5.8 5.0 4.1 3.0 2.4 2.2 2.4 3.6 299.98 10.0 124 .86 595 2.67 2.98 6.90 15.0 1984 1.78 1991 FOR 1993 HATER YEAR 2392.35 6.55 259 .74 .90 2370 11.32 .60 4750 1.75 23.80 10 2.7 1.2 Jul 11 Apr 25 Apr 1 Jul 11 Jul 11 Nov 16 2.7 2.3 e6.S e4.4 4.7 3.2 2.2 3.0 1.9 1.7 259 34 17 10 7.6 8.9 e6.5 e4.4 e3.7 e2.8 e2.3 70 76 38 15 11 e!5 e8.6 e5.2 e4.2 e4.4 636.2 20.5 259 1.7 1260 5.49 6.33 5.92 20.5 1993 1.58 1986 HATER 6. 10. 3. 472 . . 9320 17. . 4980 1. 24. 10 2. 1. e3.7 e3.9 3.4 3.2 3.2 3.4 2.8 2.8 2.8 4.1 3.7 2.8 2.8 2.5 3.3 67 15 4.7 3.4 3.0 2.5 4.2 7.6 5.3 4.1 3.9 2.3 2.2 2.0 2.0 2.3 179.9 5.80 67 2.0 357 1.55 1.79 5.50 14.4 1988 1.95 1985 YEARS 1984 - 87 4 19 Nov 27 29 Sep 12 41 May 19 May 17 10 May 17 26 May 30 84 96 1 0 2.2 2.0 2.0 2.0 2.9 2.1 1.9 2.0 2.0 5.2 3.3 2.3 2.1 2.2 2.2 5.2 3.0 3.3 3.6 e2.6 e2.3 e2.3 e9.5 e4.4 e3.0 e2.5 e2.3 e2.5 e2.7 e4.7 90.3 3.01 9.5 1.9 179 .80 .90 9.96 29.0 1989 1.88 1990 1993 1988 1990 1987 1990 1990 1985 1985 1990 e Estimated RIO GRANDB DE LOIZA BASIN 50051180 QUEBRADA SALVATIERRA NEAR SAN LORENZO, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.-- Hater 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 1993. INSTRUMENTATION.-- 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 LOADSi 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 HATER YEAR 1993.-- SEDIMENT CONCENTRATIONi Maximum daily mean, 743 mg/L July 11, 1993; Minimum daily mean, 1.0 mg/L several days. SEDIMENT LOADSi Maximum daily mean, 1,140 tons (1,030 tonnes) July 11, 1993; Minimum daily mean, <0.01 ton (<0.01 tonne) several days. SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 203 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 6.5 5.6 5.4 5.1 5.5 39 5.8 2.6 2.2 2.1 2.5 2.0 1.7 1.6 1.6 1.6 1.6 1.6 1.9 4.0 1.8 1.3 1.5 2.0 3.2 2.8 2.1 1.8 1.8 1.9 2.2 2 2 2 2 2 97 19 12 8 7 6 5 6 5 4 3 3 3 4 9 6 3 1 2 2 3 4 5 4 3 3 .04 .02 .03 .02 .02 72 .33 .09 .05 .04 .04 .04 .03 .02 .02 .02 .02 .02 .02 .19 .04 .01 .00 .00 .02 .02 .02 .03 .02 .02 .02 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) NOVEMBER 2.0 1.7 2.0 7.7 3.4 7.0 8.1 3.2 2.4 5.9 3.3 1.7 1.7 1.6 3.3 2.2 1.5 26 14 4.5 19 13 4.7 2.1 1.3 1.1 26 124 29 108 3 3 4 62 30 21 20 6 3 8 3 3 3 3 13 16 19 94 37 12 82 15 3 6 8 6 81 424 47 200 ___ .02 .02 .03 1.4 .31 .54 .57 .05 .02 .15 .03 .02 .02 .02 .19 .10 .07 14 1.7 .16 18 .73 .04 .04 .04 .02 16 463 14 314 ___ MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) DECEMBER 23 13 6.6 5.8 4.2 3.0 2.7 2.8 2.5 e2.5 e2.4 e2.3 e3.8 e3.5 e2.5 e2.2 e2.1 e2.1 e2.1 e2.1 e3.5 e2.5 e2.3 elO e7.0 e5.0 e3.5 e6.8 e4.5 e!3 e!7 111 100 44 19 15 12 8 4 2 2 4 4 3 4 8 12 8 4 3 3 4 6 5 3 3 1110 25 4 7 15 18 11 3.3 .86 .33 .16 .10 .06 .03 .02 e.02 e.03 e.03 e.04 e.03 e.06 e.07 e.04 e.02 e.02 e.02 e.04 e.04 e.04 e.09 e.06 e!5 e.23 e.09 e.08 e.51 e.83 TOTAL 122.3 73.26 431.4 845.29 166.3 33.25 e Estimated 204 RIO GRANDS DB LOIZA BASIN 50051180 QUBBRADA SALVATIBRRA NR SAN LORENZO, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 MEAN MEAN MEAN CONCBN- SEDIMENT MEAN CONCEN- 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 ell e9.0 eV.O 5.9 5.8 5.5 5.7 4.9 5.2 4.7 4.4 4.1 3.9 5.3 3.7 3.9 3.9 3.4 3.4 3.4 3.2 3.2 3.4 3.0 2.8 2.8 3.4 3.4 4.9 3.3 2.8 17 15 13 10 10 10 10 11 9 6 5 6 7 14 11 8 6 6 11 13 8 5 3 4 4 5 5 5 15 12 7 e.49 e.36 e.23 .17 .15 .16 .15 .14 .12 .08 .06 .07 .08 .24 .10 .09 .06 .06 .10 .11 .07 .04 .03 .04 .04 .04 .04 .04 .21 .11 .06 FEBRUARY 2.7 3.4 3.3 2.7 2.7 2.7 2.7 2.5 2.5 2.5 2.5 e2.9 e3.1 e3.3 e2.7 e2.4 e2.3 e2.2 e2.2 e2.2 e2.1 e2.0 el. 9 el. 7 el. 5 el. 4 el. 3 el. 4 5 9 10 7 7 6 5 5 4 4 4 5 5 5 6 9 8 6 4 3 2 2 2 2 2 2 2 2 ___ ___ ___ .04 .10 .08 .06 .06 .04 .04 .04 .03 .02 .03 e.04 e.04 e.05 e.05 e.06 e.05 e.03 e.02 e.02 e.02 e.02 e.02 e<.01 et.Ol e<.01 e<.01 e.Ol ___ ___ __- MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MARCH el. 5 el. 6 el. 2 el. 2 el. 3 el. 2 el. 2 el. 2 el.l el.l 1.2 1.2 1.2 1.0 1.0 1.0 1.9 1.6 1.9 1.8 1.6 1.3 1.3 1.3 1.2 1.2 1.1 .99 .92 .86 .86 3 2 1 1 1 3 6 7 7 6 6 6 6 6 5 5 5 5 5 5 4 5 6 6 5 5 5 4 4 5 5 e.02 e.Ol et.Ol e<.01 e<.01 e.Ol e.02 e.02 e.02 e.02 .02 .02 .02 .02 .02 .02 .02 .02 .02 .03 .02 .02 .02 .02 .02 .02 .02 .02 .02 .02 .02 TOTAL 140.3 3.74 66.8 0.97 39.03 0.55 e Estimated RIO GRANDB DB LOIZA BASIN 50051180 QUBBRADA SALVATIBRRA NR SAN LORBNZO, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 205 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 .86 .86 1.1 1.0 .87 .86 .76 .96 1.7 1.3 .98 1.0 1.4 1.8 1.8 2.1 1.4 1.2 1.5 .98 1.0 .98 .91 .78 .74 1.1 4.0 1.7 3.0 e!2 50.64 APRIL 5 5 5 5 5 4 3 1 2 3 4 3 3 2 2 3 3 3 6 7 3 3 4 5 6 7 11 6 7 14 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) MEAN DISCHARGE (CFS) MAY .02 .02 .01 .01 .01 .01 .00 .00 .00 .02 .01 .00 .00 .01 .00 .01 .02 .01 .02 .01 .01 .01 .02 .02 .02 .02 .14 .03 .06 .46 0.98 e!7 e8.0 11 4.3 3.6 3.2 1.8 1.6 7.6 5.6 2.5 1.9 1.9 33 13 5.9 3.7 2.7 2.2 2.2 2.2 1.9 1.8 1.9 1.9 2.2 6.7 5.0 2.2 1.9 1.8 162.2 14 14 36 15 7 5 5 5 18 9 4 3 3 114 29 12 4 5 5 4 7 17 12 6 5 4 e.64 e.30 1.0 .17 .07 .04 .03 .02 .42 .14 .02 .01 .02 32 1.0 .22 .04 .04 .03 .02 .02 .02 .02 .02 .02 .04 .55 .21 .04 .02 .02 37.21 1.7 1.6 1.3 1.1 .98 .93 .91 .86 1.5 3.0 1.6 1.3 1.3 20 17 8.2 3.2 16 124 43 10 12 5.8 5.0 4.1 3.0 2.4 2.2 2.4 3.6 --- 299.98 MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) JUNE 4 3 4 7 6 5 5 5 5 7 5 4 4 54 37 21 13 55 363 124 26 31 12 6 5 5 5 5 4 3 .02 .02 .02 .02 .02 .02 .02 .02 .01 .06 .02 .02 .02 5.5 1.9 .58 .11 24 182 25 .91 1.1 .19 .08 .05 .04 .03 .02 .03 .04 241.87 e Estimated 206 RIO GRANDB DE LOIZA BASIN 50051180 QOEBRADA SALVATIERRA NR SAN LORBNZO, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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 (CFS) (MG/L) (TONS/DAY) 2.7 2.3 e6.5 e4.4 4.7 3.2 2.2 3.0 1.9 1.7 259 34 17 10 7.6 8.9 e6.5 e4.4 e3.7 e2.8 e2.3 70 76 38 15 11 e!5 e8.6 e5.2 e4.2 e4.4 JULY 3 3 14 8 5 11 12 7 3 2 743 81 23 8 6 5 6 7 7 4 2 129 186 113 27 19 35 15 10 10 8 TOTAL 636.2 --- YEAR e 2385.35 Estimated .02 .02 e.25 e.10 .06 .08 .08 .05 .01 .00 1140 9.2 1.3 .25 .13 .13 e.10 e.08 e.07 e.03 e.Ol 120 69 17 1.3 .61 1.7 .34 .14 .11 .09 1362.26 2660.36 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AUGUST e3.7 e3.9 3.4 3.2 3.2 3.4 2.8 2.8 2.8 4.1 3.7 2.8 2.8 2.5 3.3 67 15 4.7 3.4 3.0 2.5 4.2 7.6 5.3 4.1 3.9 2.3 2.2 2.0 2.0 2.3 5 3 2 3 7 9 8 5 2 2 2 6 9 10 12 192 49 15 3 2 2 7 14 7 5 4 5 5 6 7 6 e.05 e.03 .02 .03 .06 .08 .07 .04 .02 .02 .02 .05 .07 .06 .10 53 2.1 .27 .03 .02 .02 .24 .35 .11 .05 .05 .02 .03 .04 .04 .04 179.9 57.13 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) SEPTEMBER 2.2 2.0 2.0 2.0 2.9 2.1 1.9 2.0 2.0 5.2 3.3 2.3 2.1 2.2 2.2 5.2 3.0 3.3 3.6 e2.6 e2.3 e2.3 e9.5 e4.4 e3.0 e2. e2. e2. e2. e4.7 90.3 6 6 7 8 12 17 12 4 2 21 18 10 5 4 3 12 11 8 6 5 5 6 30 14 7 4 4 3 3 8 .03 .03 .04 .04 .09 .09 .06 .03 .02 .31 .18 .06 .03 .02 .02 .15 .08 .08 .07 ».04 ,04 ,04 e .8 .20 .06 .03 .02 .02 .02 .15 3.85 RIO GRANDB DB LOIZA BASIN 50051180 QUBBRADA SALVATIBRRA NEAR SAN LORENZO--Continued HATER QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT 207 DATE MOV 1992 28... MAY 1993 14... •TON 14... JUL 11... 11... 22... AUG 16... TIME 0810 1045 1000 0725 1020 1650 1033 STREAM- FLOW, INSTAN- TANEOUS (CPS) 1370 147 45 300 331 193 111 SEDI- MENT, SUS- PENDED (MG/L) 1740 1160 560 2720 2060 4890 274 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 6440 460 68 2200 1840 2550 82 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 98 90 98 96 60 67 95 208 RIO GRANDB DB LOZZA BASIN 50051310 RIO CAYAGUAS AT CBRRO GORDO, PR LOCATION.—Lat 18°09'13", long 65°57'20 H , Hydrologic Unit 21010005, at downstream side of bridge on Highway 912, at Barrio Cerro Gordo, 2.8 mi (4.5 km) south of San Lorenzo. DRAINAGE ARBA.--10.2 mi 1 (26.4 km'). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--October 1977 to current year. GAGE.—Water-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. DISCHARGE, CUBIC FBBT PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 19 45 2 20 26 3 21 25 4 21 73 5 23 39 6 23 89 7 24 56 8 24 35 9 24 32 10 25 29 11 26 28 12 25 26 13 25 36 14 24 29 15 24 43 16 27 34 17 29 74 18 28 99 19 27 75 20 27 57 21 205 43 22 76 63 23 36 55 24 55 75 25 75 49 26 38 41 27 28 62 28 26 264 29 27 77 30 26 195 31 40 TOTAL 1118 1874 MEAN 36.1 62.5 MAX 205 264 MIN 19 25 AC-FT 2220 3720 CFSM 3.54 6.12 IN. 4.08 6.83 STATISTICS OF MONTHLY MEAN MEAN 64.2 74.4 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 196 76 72 55 46 43 38 35 34 33 33 33 33 33 33 32 32 32 32 33 36 34 32 35 39 80 49 34 85 65 44 1487 48.0 196 32 2950 4.70 5.42 DATA 47.0 163 1988 12.5 1992 FOR 87 55 44 36 33 57 64 53 51 43 39 38 34 37 33 34 32 33 39 31 29 41 43 33 98 42 54 70 186 48 34 1551 50.0 186 29 3080 4.91 5.66 31 33 31 28 28 28 29 29 29 27 32 34 34 26 24 24 24 23 23 24 23 22 25 25 22 22 22 21 ___ —— 743 26.5 34 21 1470 2.60 2.71 FOR WATER YEARS 1977 30.0 50.0 1993 14.6 1990 26.7 67.5 1984 11.0 1992 21 22 21 20 21 21 20 21 21 21 20 21 24 23 24 22 26 24 31 29 25 21 20 20 22 22 20 17 17 16 15 668 21.5 31 15 1320 2.11 2.44 - 1993 21.9 45.4 1989 11.3 1992 1992 CALENDAR YEAR 16713.1 45.7 831 8.5 9.0 33150 4.48 60.95 84 27 10 May 26 Apr 10 Apr 5 15 14 16 15 16 17 15 17 18 16 14 14 14 17 16 14 13 14 17 14 14 13 13 13 14 20 23 15 77 74 —— 582 19.4 77 13 1150 1.90 2.12 156 69 30 24 42 43 17 15 225 104 37 24 21 210 57 23 16 14 13 16 15 15 15 15 24 29 85 53 22 17 15 1461 47.1 225 13 2900 4.62 5.33 16 16 15 14 14 14 14 16 15 29 25 17 46 255 139 64 25 149 649 290 69 55 35 36 25 21 20 19 20 32 2154 71.8 649 14 4270 7.04 7.86 22 22 39 33 20 19 32 64 26 21 1130 177 90 61 46 104 48 35 33 32 32 280 253 128 66 53 49 37 33 32 33 3050 98.4 1130 19 6050 9.65 11.12 32 31 30 29 30 29 30 31 29 29 33 30 25 25 29 390 104 48 34 27 27 30 78 33 27 23 22 24 20 21 35 1385 44.7 390 20 2750 4.38 5.05 33 37 66 30 79 48 28 61 59 93 64 36 32 32 28 75 33 54 36 32 27 30 202 127 54 29 24 33 131 190 1803 60.1 202 24 3580 5.89 6.58 , BY WATER YEAR (WY) 20.8 46.0 1985 10.7 1980 FOR 1993 17876 49. 1130 13 14 5490 17. 13 35460 4. 65. 78 31 16 50.1 155 1985 9.68 1990 WATER YEAR 0 Jul 11 Apr 17 Apr 17 Jul 11 33 Jul 11 Apr 16 80 19 49.4 140 1979 14.4 1991 45.7 118 1979 16.0 1990 WATER 44 89 18 2900 7 8 13200 9 7 32250 4 59 69 24 13 47.4 202 1979 14.5 1991 YEARS 1977 - .5 .7 .6 Aug 31 . 1 Feb 4 . 6 Apr 7 Aug 31 .44 Aug 31 . 1 Feb 4 .36 .29 55.7 216 1979 16.9 1980 1993 1979 1990 1979 1981 1983 1979 1979 1981 RIO GRANDB DB LOIZA BASIN 50051800 RIO QRANDB DB LOIZA AT HWY 183 NEAR SAN LORBNZO, PR 209 LOCATION.--Lat 18«11'09", long 65<>57'42", Hydrologie Unit 21010005, at upatream aide of bridge on Highway 183 by-paaa, 0.4 mi (0.6 km) aouth from Plaza de San Lorenzo, 1.4 mi (2.2 km), aouthweat from Bacuela Rafael Col6n Qareia and 2.0 mi (3.2 km) northweat from Bacuela Segunda Unidad de Carlo* Zaya*. DRAINAGE ARBA.--25.0 mi a (64.8 km*). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—February 1990 to current year. GAGE.—Water-Btage recorder. Elevation of gage ia 262 ft (80 m), from topographic map. REMARKS.--Record* poor. Water purification plant located about 0.2 mi (0.3 km) upatream from gage. Gage-height and precipitation aatellite telemetry at •tation. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY •TON JUL AUG SEP 1 96 74 2 89 55 3 87 56 4 80 143 5 78 84 6 134 164 7 85 135 8 75 78 9 73 68 10 69 65 11 67 58 12 66 54 13 61 63 14 61 54 15 61 113 16 62 75 17 63 114 18 65 178 19 60 161 20 71 126 21 130 107 22 92 105 23 65 95 24 77 108 25 140 79 26 95 70 27 63 130 28 57 443 29 61 195 30 60 412 31 62 - — TOTAL 2405 3662 MEAN 77.6 122 MAX 140 443 MIN 57 54 AC-FT 4770 7260 CFSM 3.10 4.88 IN. 3.58 5.45 STATISTICS OF MONTHLY MEAN MEAN 142 153 MAX 266 222 (WY) 1991 1992 MIN 77.6 113 (WY) 1993 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 226 168 188 141 119 110 102 97 94 91 87 83 85 88 97 84 82 79 77 75 75 85 78 76 85 184 125 90 167 138 148 3424 110 226 75 6790 4.42 5.09 DATA 93.3 110 1993 82.6 1992 FOR 215 156 123 113 91 122 146 132 119 110 99 99 90 98 85 84 83 77 85 74 70 e!30 e86 elSO ellO e98 e!20 e300 e!20 e94 e84 3563 115 300 70 7070 4.60 5.30 e84 e98 84 72 68 69 68 64 63 61 70 83 e70 e62 e60 e62 e64 eS8 58 59 57 55 55 57 53 49 50 50 ___ ___ —— 1803 64.4 98 49 3580 2.58 2.68 FOR WATER YEARS 1990 123 192 1992 62.9 1991 51.0 71.1 1991 21.0 1992 48 50 46 44 44 44 42 42 43 40 40 41 45 44 45 41 51 50 58 54 47 38 36 38 39 45 40 35 32 30 29 1321 42.6 58 29 2620 1.70 1.97 - 1993 36.7 48.7 1991 17.4 1992 1992 CALENDAR YEAR 46830.0 128 3380 6.3 7.4 92890 5.12 69.68 199 75 14 Jan 5 Apr 29 Apr 25 27 28 28 29 26 27 24 29 45 36 27 26 28 46 34 31 el!7 e30 e36 e32 e35 e27 37 25 24 34 50 29 139 139 ... 1245 41.5 139 24 2470 1.66 1.85 250 306 138 81 90 93 56 50 191 133 73 56 48 362 145 89 70 65 57 58 56 53 52 53 61 97 105 86 57 50 46 3127 101 362 46 6200 4.03 4.65 50 46 38 38 41 41 39 41 45 61 64 43 68 211 226 154 79 184 e!300 e668 e327 e264 e!24 e!09 e81 e71 e64 e59 e58 e90 --- 4684 156 1300 38 9290 6.25 6.97 e59 e56 elOl e73 e54 e47 e55 e95 e54 e44 e!890 e262 e204 175 155 237 156 137 129 120 118 436 379 322 234 197 191 140 122 110 105 6457 208 1890 44 12810 8.33 9.61 103 97 89 85 83 80 77 81 74 78 85 76 67 62 70 449 177 103 87 81 78 81 210 152 99 87 79 76 72 68 91 3197 103 449 62 6340 4.13 4.76 84 86 103 70 105 82 65 102 107 204 124 82 74 73 67 137 81 174 95 96 69 67 264 166 92 79 69 73 185 223 --- 3298 110 264 65 6540 4.40 4.91 , BY WATER YEAR (WY) 29.5 41.5 1993 16.8 1992 FOR 1993 38186 105 1890 24 27 14600 21. 75740 4. 56. 177 78 40 89.6 186 1992 35.1 1991 WATER YEAR Jul 11 Apr 7 Apr 1 Jul 11 50 Jul 11 18 82 144 290 1992 47.8 1991 117 208 1993 66.0 1990 WATER 107 134 82. 3380 6. 7. 28200 27. 77530 4. 58. 168 58 22 97.8 132 1992 48.6 1991 YEARS 1990 - 2 Jan 5 3 Apr 29 4 Apr 25 Jan 5 3 6 Jan 5 28 16 129 255 1992 59.7 1990 1993 1992 1991 1992 1992 1992 1992 1992 e Estimated 210 RIO GRANDE DE LOIZA BASIN 50051800 RIO GRANDE DB LOIZA AT HWY 183 NEAR SAN LORENZO, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORDS.— Water years 1990 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE! February 1990 to September 1993. INSTRUMENTATION.-- DH-48 and automatic sediment sampler. in, 1,570 mg/L Jun. 11, 1992; Minimum dally mean, EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATION< Maximum dally 5 mg/L Several days. SEDIMENT LOADSt Maximum daily mean, 46,800 tons (42,400 tonnes) Jan. 05, 1992; Minimum daily mean, 0.20 ton (0.18 tonne) May 05, 1992. EXTREMES FOR WATER YEAR 1993.-- Water Year 1993 Suspended-sediment concentration (mg/L) maximum minimum Suspended-sediment discharge (tons per day) maximum minimum 2,750 (July 11) 4 (Several days) e30,800 (July 11) SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 .73 (May, 23) MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) OCTOBER MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) NOVEMBER MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) 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 29 30 31 96 89 87 80 78 134 85 75 73 69 67 66 61 61 61 62 63 65 60 71 130 92 65 77 140 95 63 57 61 60 62 19 18 21 25 26 110 64 13 13 13 13 12 12 12 12 13 13 19 43 71 137 83 22 48 134 54 16 18 19 21 20 4.8 4.3 4.9 5.4 5.4 81 17 2.7 2.7 2.6 2.4 2.2 1.9 2.0 2.0 2.1 2.3 3.2 7.1 15 82 28 3.6 20 60 20 2.7 2.7 3.1 3.7 3.4 74 55 56 143 84 164 135 78 68 65 58 54 63 54 113 75 114 178 161 126 107 105 95 108 79 70 130 443 195 412 74 55 53 135 82 163 115 34 17 25 35 37 35 35 96 49 135 172 154 69 62 63 33 85 25 6 95 467 205 414 16 8 8 63 20 86 48 7 3 4 5 5 6 5 47 11 49 110 76 25 22 17 8 29 6 1 57 1360 124 882 .4 .2 .7 .0 .5 .9 .4 .1 .4 .7 .3 .2 226 168 188 141 119 110 102 97 94 91 87 83 85 88 97 84 82 79 77 75 75 85 78 76 85 184 125 90 167 138 148 448 133 142 46 11 8 7 7 8 6 4 4 4 4 7 7 8 7 5 4 4 6 6 5 5 165 157 129 171 140 152 396 69 81 19 3.6 2.5 2.0 2.0 2.1 1.5 .94 .91 .93 1.1 1.8 1.8 1.8 1.5 1.2 .94 .95 1.3 1.4 1.0 1.2 129 57 31 82 56 70 TOTAL 2405 400.2 3662 3112.8 3424 1022.47 RIO GRANDB DE LOIZA BASIN 211 50051800 RIO 6RANOB DE LOIZA AT HWY 183 NEAR SAN LORBNZO,PR——Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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 31 215 156 123 113 91 122 146 132 119 110 99 99 90 98 85 84 83 77 85 74 70 e!30 e86 e!50 ellO e98 e!20 e300 e!20 e94 e84 152 142 137 116 88 101 142 79 17 7 6 6 6 4 4 5 6 7 6 6 6 98 59 10 10 10 10 295 115 90 52 90 65 48 35 20 36 60 34 4.9 2.1 1.8 1.6 1.6 1.3 1.1 1.3 1.4 1.5 1.5 1.2 1.2 e47 el4 e4.1 e3.0 e2.6 e3.2 e239 e37 e23 e!2 FEBRUARY e84 e98 84 72 68 69 68 64 63 61 70 83 e70 e62 e60 e62 e64 e58 58 59 57 55 55 57 53 49 50 50 ___ ___ 35 38 38 33 33 37 46 45 27 17 21 28 31 32 31 29 26 21 18 19 22 24 25 26 27 27 27 27 7.9 9.9 8.5 6.3 6.1 6.9 8.4 7.8 4.5 2.7 4.0 6.2 e5.9 e5.4 e5.0 e4.8 e4.4 e3.3 2.8 2.9 3.3 3.5 3.9 4.1 3.9 3.7 3.6 3.6 ___ ___ MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) MARCH TOTAL 3563 795.4 1803 143.3 48 50 46 44 44 44 42 42 43 40 40 41 45 44 45 41 51 50 58 54 47 38 36 38 39 45 40 35 32 30 29 1321 28 28 29 33 34 28 21 16 20 29 41 43 45 47 49 51 50 49 45 42 37 37 39 52 62 60 52 49 49 56 79 3.7 3.8 3.6 4.0 4.2 3.4 2.5 1.8 2.4 3.2 4.5 5.0 5.3 5.7 6.0 5.6 6.6 6.6 6.6 6.1 4.8 3.7 3.9 5.4 6.5 7.6 5.9 4.6 4.3 4.8 6.5 148.6 e Estimated 212 RIO GRANDE OB LOIZA BASIN 50051800 RIO GRANDE DE LOIZA AT HWY 183 NEAR SAN LORENZO,PR——Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 MEAN MEAN MEAN CONCBN- 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 27 28 28 29 26 27 24 29 45 36 27 26 28 46 34 31 el!7 e30 e36 e32 e35 e27 37 25 24 34 SO 29 139 139 APRIL 97 87 62 47 26 60 107 124 110 88 81 75 78 110 151 183 178 173 170 170 174 187 148 169 122 107 10S 101 134 176 MAY 6.9 6.9 4.9 3.6 1.9 4.4 7.4 10 13 8.3 6.1 5.3 6.0 13 14 16 eS6 e!6 e20 e!7 e20 e!6 13 12 8.5 10 14 8.2 131 71 2SO 306 138 81 90 93 56 50 191 133 73 56 48 362 14S 89 70 65 57 58 56 S3 52 S3 61 97 105 86 57 SO 46 248 312 109 78 85 56 23 17 181 76 41 21 20 326 143 57 24 17 14 11 8 6 5 6 10 38 78 74 19 7 6 307 516 54 18 21 17 3.7 2.4 141 29 9.1 3.3 2.7 865 63 14 4.7 2.9 2.2 1.6 1.4 .96 .73 .94 1.7 9.7 32 21 3.0 1.0 .75 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) JUNE SO 46 38 38 41 41 39 41 45 61 64 43 68 211 226 154 79 184 e!300 e668 e327 e264 e!24 e!09 e81 e71 e64 eS9 eS8 e90 ___ 8 13 IS IS 12 9 8 10 IS 28 38 20 S3 208 220 127 68 250 1350 563 72 233 110 66 43 23 8 8 24 81 ___ 1.1 1.5 1.5 1.5 1.3 .99 .84 1.1 1.8 5.4 7.7 2.3 IS 179 175 66 14 543 e61SO 1350 e71 e!83 e39 e!9 e9.3 e4.S el.S el. 2 e4.3 e20___ TOTAL 1245 540.4 3127 2150.78 4684 8871.83 e Estimated RIO GRANDE DE LOIZA BASIN 273 50051800 RIO GRANDE DE LOIZA AT HWY 183 NEAR SAN LORBNZO,PR——Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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) e59 e56 elOl e73 e54 e47 e55 e95 e54 e44 e!890 e262 e204 175 155 237 156 137 129 120 118 436 379 322 234 197 191 140 122 110 105 MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/ DAY) JULY 80 63 49 36 25 18 35 86 31 20 2750 315 70 31 11 237 39 17 13 9 8 1430 419 216 58 33 88 41 20 8 6 TOTAL 6457 YEAR e 38186 Estimated MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AUGUST e!3 e9.7 e!3 e7.8 e3.5 e2.2 e7.6 e24 e4.9 e2.3 e30800 e244 e39 15 4.5 187 18 6.1 4.3 2.9 2.5 7150 443 196 42 22 50 16 6.7 2.5 1.7 39341.2 59749.48 103 97 89 85 83 80 77 81 74 78 85 76 67 62 70 449 177 103 87 81 78 81 210 152 99 87 79 76 72 68 91 3197 5 5 5 5 5 6 9 11 15 19 55 38 19 17 40 501 51 20 21 21 20 30 168 162 50 19 17 14 11 10 12 —— 1.5 1.3 1.2 1.1 1.1 1.4 2.0 2.4 2.9 3.7 15 9.1 3.4 2.8 9.3 936 29 5.6 4.8 4.5 4.3 7.5 114 74 14 4.7 3.5 2.7 2.0 1.8 3.0 1269.6 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) SEPTEMBER 84 86 103 70 105 82 £5 102 107 204 124 82 74 73 67 137 81 174 95 96 £9 67 264 166 92 79 £9 73 185 223 16 23 40 25 60 111 56 86 135 153 74 41 27 20 17 109 56 176 115 67 76 65 270 166 61 21 12 15 196 219 3.8 5.8 12 4.8 25 27 10 35 45 97 28 8.S 5.4 3.8 3.2 52 12 197 32 16 15 12 899 91 16 4.7 2.2 3.3 139 147 3298 1952.9 214 RIO GRANDE DE LOIZA BASIN 50051800 RIO GRANDE DE LOIZA AT HWY 183 NEAR SAN LORENZO, PR--Continued HATER QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT DATE NOV 1992 30... DEC 01... MAY 1993 14. .. JUL 11... 22... SEP 23. .. TIME 0940 1401 1020 1150 1830 1815 DIS- CHARGE, INST. CUBIC FEET PER SECOND 290 583 1820 2600 4230 2930 SEDI- MENT, SUS- PENDED (MG/L) 3980 33000 5580 4570 2670 22500 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 3120 51900 27400 32100 30500 178000 SED. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM 49 7 25 26 36 10 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM 54 8 30 31 40 12 SED. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 57 9 40 35 44 14 DATE NOV 1992 30... DEC 01... MAY 1993 14. .. JUL 11... 22... SEP 23.. . SBD. SUSP. FALL DIAM. PERCENT FINER THAN .016 MM 56 11 54 45 51 18 SED. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM 72 21 71 60 59 25 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 92 40 86 74 71 40 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 98 74 96 93 88 67 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 99.4 93 99 97 95 88 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 99.7 99.6 99.8 99 99 98 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 99.8 100 100 99 100 100 RIO GRANDS DE LOIZA BASIN 50051800 RIO GRANDB DE LOIZA AT HWY 183 NEAR SAN LORENZO, PR--Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT 215 DATE NOV 1992 18... DEC 01... JAN 1993 29... APR 19.. . JUN 14... 18... 19... JUL 11... 22... SEP 23... TIME 0935 1516 1000 0940 0940 2330 0530 0930 2030 1815 STREAM- FLOW, INSTAN- TANEOUS (CFS) 83 489 120 44 136 1590 945 2050 909 2930 SEDI- MENT, SUS- PENDED (MG/L) 351 1640 2670 368 3110 4980 498 1730 6680 13000 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 79 2160 865 44 1140 21380 1270 9580 16400 102800 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 99 83 99 94 93 55 89 74 57 48 216 RIO GRANDS DB LOIZA BASIN 50053025 RIO TORABO ABOVE BORINQUBN, PR LOCATION.--Lat 18°09'35", long 66°02'26", Hydrologic Unit 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 Lo£za. DRAINAGE AREA.--7.14 mi* (18.49 km1 ). WATER-DISCHARGE RECORDS PERIOD OP RECORD.—January 1990 to current year. GAGB.—Water-Btage recorder and crest-stage gage. Elevation of gage is 492 ft (150 m)/ from topographic REMARKS.--Records fair. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 12 8.1 2 12 7.4 3 11 7.0 4 10 21 5 10 11 6 47 49 7 17 22 8 13 10 9 12 9.5 10 11 13 11 10 9.0 12 10 8.6 13 9.3 8.5 14 9.3 7.7 15 9.2 9.1 16 10 9.0 17 8.7 8.4 18 8.6 21 19 8.4 13 20 7.9 11 21 7.4 9.3 22 9.2 11 23 8.7 9.7 24 8.8 9.0 25 10 8.4 26 8.6 7.9 27 7.6 64 28 7.3 116 29 7.1 22 30 7.0 41 31 10 TOTAL 338.1 561.6 MEAN 10.9 18.7 MAX 47 116 MIN 7.0 7.0 AC-PT 671 1110 CPSM 1.53 2.62 IN. 1.76 2.93 STATISTICS OP MONTHLY MEAN MEAN 23.3 25.1 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 PLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW PLOW ANNUAL RUNOFF (AC- FT) ANNUAL RUNOFF (CPSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 37 20 25 17 14 12 11 10 9.6 9.4 8.8 8.3 8.3 13 11 8.5 8.2 8.1 8.5 7.7 7.6 13 8.8 8.6 10 60 19 12 16 15 45 470.4 15.2 60 7.6 933 2.13 2.45 DATA 17.7 23.1 1991 14.9 1992 POR 47 34 22 17 15 16 26 17 18 14 13 12 11 12 11 10 10 10 11 9.7 9.1 15 13 10 28 13 13 15 22 13 11 497.8 16.1 47 9.1 987 2.25 2.59 10 11 11 10 9.9 9.5 9.3 9.2 9.0 8.6 9.4 11 11 9.4 8.9 8.6 8.0 8.6 8.3 8.3 8.9 8.0 8.0 7.7 7.4 7.7 7.4 7.4 -__ --- 251.5 8.98 11 7.4 499 1.26 1.31 POR WATER YEARS 1990 21.7 47.5 1992 7.85 1990 12.6 18.1 1991 8.93 1990 7.1 7.4 7.1 7.4 7.3 6.8 6.6 6.5 6.5 6.4 6.8 7.1 7.1 6.8 8.0 7.1 11 9.3 13 9.0 7.7 6.9 6.8 6.8 6.9 7.4 6.8 6.7 6.2 5.8 5.7 228.0 7.35 13 5.7 452 1.03 1.19 - 1993 9.83 11.6 1991 7.35 1993 1992 CALENDAR YEAR 8212.6 22.4 605 5.1 5.5 16290 3.14 42.79 38 12 7.3 Jan 5 Apr 29 Apr 24 5.7 S5.7 6.1 6.1 5.7 5.8 5.7 13 15 12 8.5 7.6 20 12 17 10 11 6.7 6.2 6.5 6.4 6.0 6.2 5.6 6.0 8.1 7.5 10 48 32--- 322.1 10.7 48 5.6 639 1.50 1.68 126 116 39 17 14 12 9.9 12 22 15 12 9.9 9.1 290 40 20 17 15 14 13 12 12 13 12 16 33 20 16 12 11 10 989.9 31.9 290 9.1 1960 4.47 5.16 11 10 9.3 9.1 8.7 8.7 8.7 9.4 9.3 11 10 8.5 11 36 60 29 13 27 276 115 33 105 35 25 19 16 14 13 13 23 976.7 32.6 276 8.5 1940 4.56 5.09 12 13 32 16 12 11 11 18 12 11 510 92 42 31 26 48 23 20 17 16 15 94 139 204 70 48 38 31 30 27 24 1693 54.6 510 11 3360 7.65 8.82 21 19 17 16 15 14 14 14 13 14 15 13 12 12 15 199 32 20 17 14 13 15 43 26 18 16 14 14 13 13 17 708 22.8 199 12 1400 3.20 3.69 14 14 14 12 13 12 10 15 12 42 15 11 10 9.8 13 12 9.5 8.5 7.5 6.8 6.9 6.4 36 13 7.5 6.6 6.5 14 54 23 435.0 14.5 54 6.4 863 2.03 2.27 , BY WATER YEAR (WY) 8.21 10.7 1993 6.18 1990 POR 1993 7472. 20. 510 5. 5. 3380 14. 5. 14820 2. 38. 34 11 7. 20.5 31.9 1993 8.99 1990 WATER YEAR 1 5 Jul 11 6 Apr 24 8 Mar 30 Jul 11 14 Jul 11 5 Apr 6 87 93 0 27.8 48.9 1992 9.59 1991 27.5 54.6 1993 15.6 1992 WATER 20. 24. 18. 605 4. 4. 3590 14. 3. 15110 2. 39. 32 11 6. 19.3 22.8 1993 10.8 1991 YEARS 1990 - 9 0 1 Jan 5 1 May 23 4 Aug 8 Jan 5 37 Jan 5 9 May 22 92 68 0 19.7 28.1 1992 14.1 1990 1993 1992 1991 1992 1990 1991 1992 1992 1990 RIO GRANDB DB LOIZA BASIN 50053025 RIO TURABO ABOVE BORINQUEN, PR—Continued WATER-QUALITY RECORDS PERIOD OP RECORDS.— Water years 1990 to current year. PERIOD OP DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: January 1990 to September 1993. INSTRUMENTATION.— DH-48 and automatic sediment sampler. EXTREMES POR PERIOD OP DAILY RECORD.-- SEDIMENT CONCENTRATION: Maximum daily mean, 1,030 mg/L July 11, 1993; 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. 217 EXTREMES FOR WATER YEAR 1993.-- Water Year 1993 Suspended-sediment concentration (mg/L) maximum minimum Suspended-sediment discharge (tons per day) maximum minimum 1,030 (July 11) 2 (Several days) 3,380 (July 11) .04 (Several days) SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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) OCTOBER 12 12 11 10 10 47 17 13 12 11 10 10 9.3 9.3 9.2 10 8.7 8.6 8.4 7.9 7.4 9.2 8.7 8.8 10 8.6 7.6 7.3 7.1 7.0 10 20 20 20 20 20 296 86 24 12 12 14 17 18 21 24 26 26 24 21 17 12 9 8 9 9 13 18 20 18 13 12 .67 .62 .57 .54 .57 96 4.4 .87 .37 .34 .38 .43 .46 .52 .61 .63 .60 .55 .48 .36 .24 .22 .22 .21 .28 .30 .37 .38 .33 .24 .43 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) NOVEMBER 8.1 7.4 7.0 21 11 49 22 10 9.5 13 9.0 8.6 8.5 7.7 9.1 9.0 8.4 21 13 11 9.3 11 9.7 9.0 8.4 7.9 64 116 22 41___ 12 12 12 26 8 76 70 41 19 15 14 12 12 12 14 17 18 35 14 12 16 22 23 21 20 19 188 246 25 66 ___ .28 .22 .23 2.3 .28 20 5.1 1.2 .47 .54 .32 .26 .25 .24 .32 .41 .40 4.0 .53 .34 .40 .62 .63 .49 .45 .39 111 384 1.8 9.4 ___ MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) DECEMBER 37 20 25 17 14 12 11 10 9.6 9.4 8.8 8.3 8.3 13 11 8.5 8.2 8.1 8.5 7.7 7.6 13 8.8 8.6 10 60 19 12 16 15 45 61 28 28 14 12 11 10 9 8 9 10 10 10 14 14 11 10 8 7 5 4 17 19 17 15 128 33 29 28 30 73 11 1.7 2.2 .67 .42 .34 .29 .23 .20 .22 .23 .22 .22 .70 .44 .24 .21 .19 .16 .11 .08 .88 .47 .38 .40 66 1.9 .97 1.2 1.3 14 TOTAL 338.1 113.19 561.6 546.87 470.4 107.57 218 RIO GRANDB DB LOIZA BASIN 50053025 RIO TURABO ABOVE BORINQUBN, PR——Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (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 47 34 22 17 15 16 26 17 18 14 13 12 11 12 11 10 10 10 11 9.7 9.1 15 13 10 28 13 13 15 22 13 11 73 37 23 17 12 8 30 18 11 14 9 8 8 8 8 9 10 11 10 9 7 16 19 16 50 26 17 11 25 17 8 12 4.5 1.4 .82 .48 .32 4.4 .93 .53 .54 .31 .28 .25 .25 .24 .24 .26 .31 .26 .23 .17 1.3 .74 .45 7.4 .97 .55 .40 1.7 .66 .26 FEBRUARY 10 11 11 10 9.9 9.5 9.3 9.2 9.0 8.6 9.4 11 11 9.4 8.9 8.6 8.0 8.6 8.3 8.3 8.9 8.0 8.0 7.7 7.4 7.7 7.4 7.4 .15 .08 .07 .08 .08 .09 .11 .13 .14 .15 .17 .20 .17 .11 .11 .11 .17 .20 .12 .07 .08 .07 .08 .08 .08 .08 .08 .08 MEAN DISCHARGE (CFS) 7.1 7.4 7.1 7.4 7.3 6.8 6.6 6.5 6.5 6.4 6.8 7.1 7.1 6.8 8.0 7.1 11 9.3 13 9.0 7.7 6.9 6.8 6.8 6.9 7.4 6.8 6.7 6.2 5.8 5.7 MEAN CONCEN- TRATION (MG/L) MARCH 4 3 3 2 2 2 2 2 2 2 2 2 2 3 3 3 3 3 3 3 3 3 3 4 5 6 7 9 8 7 6 SEDIMENT DISCHARGE (TONS/DAY) .08 .06 .06 .05 .04 .04 .04 .04 .04 .04 .04 .04 .05 .06 .06 .06 .08 .08 .12 .07 .06 .06 .07 .09 .10 .12 .14 .15 .13 .10 .09 TOTAL 497.8 43.15 251.5 3.14 228.0 2.26 RIO GRANDB DB LOIZA BASIN 50053025 RIO TURABO ABOVE BORINQUEN, PR——Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 219 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 5.7 5.7 6.1 6.1 5.7 5.8 5.7 13 15 12 8.5 7.6 20 12 17 10 11 6.7 6.2 6.5 6.4 6.0 6.2 5.6 6.0 8.1 7.5 10 48 32 ___ APRIL 5 6 7 9 11 12 7 12 19 10 6 4 25 10 18 10 15 15 14 11 10 10 10 10 8 8 6 11 103 44 .09 .10 .12 .15 .17 .17 .10 .80 1.7 .51 .16 .09 4.6 .35 1.9 .28 .47 .26 .23 .20 .16 .16 .16 .15 .14 .19 .12 .56 62 11 ___ MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MAY 126 116 39 17 14 12 9.9 12 22 15 12 9.9 9.1 290 40 20 17 15 14 13 12 12 13 12 16 33 20 16 12 11 10 445 279 55 16 11 10 7 11 29 15 10 7 8 557 52 6 2 2 2 2 2 2 4 6 14 52 23 13 6 6 6 400 197 8.0 .81 .43 .34 .20 .78 2.0 .68 .33 .19 .23 1340 7.0 .38 .09 .08 .08 .07 .06 .08 .17 .21 .70 15 1.6 .65 .20 .18 .17 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) JUNE 11 10 9.3 9.1 8.7 8.7 8.7 9.4 9.3 11 10 8.5 11 36 60 29 13 27 276 115 33 105 35 25 19 16 14 13 13 23 6 6 6 9 8 5 5 5 5 5 5 5 5 52 112 38 11 49 799 242 49 227 21 11 8 8 12 17 20 27 .16 .16 .16 .22 .20 .12 .12 .12 .12 .14 .14 .12 .16 11 57 5.1 .42 30 829 124 5.2 116 2.4 .73 .44 .33 .42 .58 .84 2.2 TOTAL 322.1 87.09 989.9 1977.71 976.7 1187.60 220 RIO QRANDB DB LOIZA BASIN 50053025 RIO TDRABO ABOVE BORINQUBN, PR——Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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) 12 13 32 16 12 11 11 18 12 11 510 92 42 31 26 48 23 20 17 16 15 94 139 204 70 48 38 31 30 27 24 1693 7472.1 MEAN CONCEN- TRATION (MG/L) JULY 10 10 43 19 12 10 10 20 10 9 1030 23 13 8 6 77 23 17 18 19 20 283 384 365 26 20 10 10 10 10 12 ... SEDIMENT DISCHARGE (TONS/ DAY) .33 .33 6.5 .96 .38 .28 .31 1.2 .33 .30 3380 7.2 1.6 .76 .43 23 1.5 .84 .80 .82 .81 329 220 309 5.5 2.6 1.1 .87 .80 .73 .75 4299.03 9162.90 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AUGUST 21 19 17 16 15 14 14 14 13 14 15 13 12 12 15 199 32 20 17 14 13 15 43 26 18 16 14 14 13 13 17 16 17 16 14 13 12 13 13 10 6 4 4 4 4 11 593 12 8 12 14 15 17 77 34 14 12 12 11 10 10 9 .84 .90 .78 .58 .50 .45 .53 .53 .35 .23 .17 .15 .15 .12 .51 632 1.4 .46 .50 .52 .48 .85 19 3.3 .65 .52 .42 .37 .32 .31 .45 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) SEPTEMBER 14 14 14 12 13 12 10 15 12 42 15 11 10 9. 13 12 9. 8. 7. 6. 6. 6. 36 13 7. 6. 6. 14 54 23 8 5 5 5 8 9 4 5 6 5 7 6 4 4 6 11 15 22 12 65 10 12 14 13 16 11 5 5 5 5 5 5 74 10 5 5 5 14 153 26 .27 .23 .18 .13 .19 .34 .40 1.4 .45 17 .46 .35 .38 .34 .89 .43 .12 .10 .10 .10 .09 .08 41 .54 .10 .09 .09 1.1 58 2.0 708 668.34 435.0 126.95 RIO GRANDS DE LOIZA BASIN 50053025 RIO TURABO ABOVE BORINQUEN, PR--Continued WATER QUALITY DATA, WATER YEAR DECEMBER 1992 TO SEPTEMBER 1993 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT 221 DATE MAY 1993 01... 01... JUL 11. .. TIME 1345 1810 1312 DIS- CHARGE, INST. CUBIC FEET PER SECOND 470 418 1610 SEDI- MENT, SUS- PENDED (MG/L) 3690 3790 11500 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 4680 4280 50000 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM 49 43 23 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM 60 51 28 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 70 58 31 DATE MAY 1993 01... 01... JUL 11... SBD. SUSP. FALL DIAM. PERCENT FINER THAN .016 MM 81 71 38 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM 89 86 47 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 97 96 61 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 99 99 77 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 99.7 99.4 88 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 99.9 99.7 96 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 100 100 100 222 RIO GRANDB DE LOIZA BASIN 50053025 RIO TURABO ABOVE BORINQUEN, PR--Continued HATER QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT DATE OCT 1992 06... 06... NOV 25... FBB 1993 08... APR 15... MAY 01.. . JUN 13... JUL 11... SEP 24.. . TIME 1605 1955 1345 1434 1753 1325 1200 0912 1540 STREAM- FLOW, INSTAN- TANEOUS (CFS) 265 60 8.6 9.6 10 530 13 564 10 SEDI- MENT, SUS- PENDED (MG/L) 14300 935 394 85 448 2520 1150 2230 391 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 10230 154 9.1 2.2 12 3610 40 3400 11 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 32 98 96 77 98 95 98 94 99 RIO QRANDB DB LOIZA BASIN 50055000 RIO GRANDB DB LOIZA AT CAGUAS, PR 223 LOCATION.--Lat 18014'33", long 66000'34", Hydrologic Unit 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 de Caguas. DRAINAGE AREA.--89.8 mi> (232.6 km'). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—1959 (low-flow measurement only), February to November 1959 (monthly measurements only), December 1959 to current year. GAGE.—Water-stage recorder. Datum of gage is 143.28 ft (43.672 m) above mean sea level. REMARKS.--Records good 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 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 93 98 2 90 77 3 84 113 4 82 238 5 80 156 6 362 208 7 235 238 8 108 117 9 94 98 10 91 216 11 90 104 12 87 84 13 80 94 14 78 80 15 77 148 16 78 124 17 78 189 18 93 739 19 94 286 20 88 174 21 174 160 22 164 141 23 88 158 24 91 153 25 204 134 26 139 115 27 86 446 28 79 2200 29 79 410 30 86 1970 31 77 —— TOTAL 3429 9468 MEAN 111 316 MAX 362 2200 MIN 77 77 AC-FT £800 18780 CFSM 1.23 3.51 IN. 1.42 3.92 STATISTICS OF MONTHLY MEAN MEAN 379 316 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 559 324 284 232 188 163 147 133 126 121 115 109 106 262 205 117 109 105 103 98 100 130 113 103 112 1070 286 153 323 258 476 6730 217 1070 98 13350 2.42 2.79 DATA 232 714 1988 33.6 1968 .FOR 518 282 232 196 166 180 232 222 176 157 137 137 126 138 120 114 111 107 115 99 92 102 157 101 175 125 116 144 350 146 113 5186 167 518 92 10290 1.86 2.15 99 99 115 92 87 84 84 80 79 75 78 90 108 82 74 71 73 74 69 70 71 68 66 69 64 64 66 60 --- 2211 79.0 115 60 4390 .88 .92 FOR WATER YEARS 1960 149 559 1992 45.3 1968 110 291 1984 35.6 1968 60 61 57 52 53 52 50 49 48 52 49 49 53 52 52 e50 e62 e61 e70 e66 e56 e46 e44 e47 e48 e54 e50 e43 e39 e37 e36 1598 51.5 70 36 3170 .57 .66 - 1993 89.8 306 1989 23.2 1968 1992 CALENDAR YEAR 80283 219 7930 30 34 159200 2.44 33.26 323 98 48 Jan 5 Apr 28 Apr 24 e35 34 38 35 32 33 33 33 70 70 49 50 64 98 277 117 84 57 64 52 69 51 49 55 45 52 101 66 388 308 —— 2509 83.6 388 32 4980 .93 1.04 848 1150 343 149 111 186 121 90 343 252 124 97 81 1880 323 157 116 104 95 91 94 86 84 88 86 179 154 158 92 77 72 7831 253 1880 72 15530 2.81 3.24 72 72 64 59 57 54 51 54 64 77 86 61 74 451 363 312 99 111 3730 1600 337 563 263 199 146 126 111 103 103 160 —— 9622 321 3730 51 19090 3.57 3.99 108 104 189 156 100 86 95 183 105 85 6490 954 368 264 215 415 207 169 151 139 131 1350 1710 1190 464 310 344 217 185 167 157 16808 542 6490 85 33340 6.04 6.96 148 139 130 120 120 117 110 115 107 115 112 115 97 93 96 1780 352 177 145 127 118 171 383 219 149 132 126 112 103 101 116 £045 195 1780 93 11990 2.17 2.50 121 111 136 103 130 184 107 101 166 265 207 120 103 105 94 181 122 328 157 128 102 91 632 356 152 120 98 103 316 393 5332 178 632 91 10580 1.98 2.21 , BY WATER YEAR (WY) 84.7 226 1985 38.0 1968 FOR 1993 76769 210 6490 32 34 28400 20. 29 152300 2. 31. 343 110 53 254 863 1985 33.7 1974 WATER YEAR Jul 11 Apr 5 Apr 2 Jul 11 49 Jul 11 Apr 8 34 80 262 1283 1979 34.1 1975 233 660 1961 21.8 1974 WATER 219 526 82. 17900 11 11 71500 31. 158900 2. 33. 364 106 40 257 949 1979 53.6 1967 YEARS 1960 3 Oct Apr Apr Sep 17 Sep 44 18 256 764 1979 37.4 1967 - 1993 1979 1967 9 1970 8 1968 8 1968 6 1960 6 1960 e Estimated 224 RIO GRANDB DB LOIZA BASIN 50055000 RIO GRANDB DB LOIZA AT CAGDAS, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--Hater years 1959 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGEt October 1983 to September 1989. INSTRUMENTATION.-- USD-49 and automatic sediment sampler. , 14,500 mg/L Nov. 27, 1987; Minimum daily mean. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCBNTRATIONi Maximum daily m 8 mg/L Jan. 23, 1992. SEDIMENT LOADSt Maximum daily mean, 227,000 tons (205,890 tonnes) Nov. 27, 1987; Minimum daily mean, 1.3 tons (1.2) July 14, 1985. 1,660 mg/L July 11, 1993; minimum daily mean, EXTREMES FOR HATER YEAR 1993.-- SBDIMBNT CONCENTRATION! Maximum daily m 8 mg/L several days. SBDIMBNT LOADSt Maximum daily mean, 64,100 tons (58,200 tonnes) July 11, 1993; minimum daily 1.9 ton (1.7 tonnes) Oct. 05, 1992. WATER-QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATS OCT 1992 09. .. DEC 14... FEB 1993 24... APR 16... JUN 17... AUG 12... DATE OCT 1992 09... DEC 14... FBB 1993 24... APR 16... JUN 17... AUG 12... TIME 1115 1245 1310 1215 1530 1310 HARD- NESS TOTAL (MG/L AS CACO3) 75 -- -- 70 -- 67 DIS- CHARGE, INST. CUBIC FEET PER SECOND 93 110 69 100 97 97 HARD- NESS NONCARB WH HAT TOT FLD MG/L AS CACO3 0 -- -- 1 -- 0 SPE- CIFIC CON- DUCT- ANCE (US/CM) 254 248 198 263 254 220 CALCIUM DIS- SOLVED (MG/L AS CA) 19 -- -- 17 -- 17 PH HATER WHOLE FIELD (STAND- ARD UNITS) 7.5 7.6 7.7 6.6 6.9 7.1 MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) 6.7 -- -- 6.6 -- 5.9 TEMPER- ATURE HATER (DBG C) 28.0 25.6 25.4 24.5 29.9 30.1 SODIUM, DIS- SOLVED (MG/L AS NA) 21 __ -- 18 -- 19 TUR- BID- ITY (NTU) 12 27 53 300 24 20 SODIUM AD- SORP- TION RATIO 1 __ -- 0.9 -- 1 OXYGEN, DIS- SOLVED (MG/L) 6.9 7.9 7.7 4.4 6.8 5.5 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 2.3 -- -- 2.8 -- 2.0 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 87 92 91 52 84 76 ALKA- LINITY HAT WH TOT FET FIELD MG/L AS CACO3 82 67 84 57 75 58 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) <10 18 41 20 20 <10 SULFIDB TOTAL (MG/L AS S) <0.5 -- -- <0.5 -- -- COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 32000 K6900 5300 K69000 K7400 52000 SULFATB DIS- SOLVED (MG/L AS SO4) 13 -- -- 16 -- 11 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) K1500 600 250 44000 4000 240 CHLO- RIDE, DIS- SOLVED (MG/L AS CL) 17 -- -- 16 -- 17 FLUO- SILICA, RIDE, DIS- DIS- SOLVED SOLVED (MG/L DATE (MG/L AS AS F) SI02) OCT 1992 09... 0.10 33 DEC 14... FEB 1993 24... APR 16... <0.10 22 JUN 17... AUG 12... 0.10 33 K = non- ideal count SOLIDS, RESIDUE SUM OF SOLIDS, TOTAL CONSTI- DIS- AT 105 TUBNTS, SOLVED DBG. C, DIS- (TONS SUS- SOLVBD PER FENDED (MG/L) DAY) (MG/L) 161 40.3 8 16 73 133 35.8 502 36 150 39.3 25 NITRO- GEN, NITRATE TOTAL (MG/L AS 0 0 0 0 0 0 N) .350 .370 .450 .600 .260 .330 NITRO- GEN, NITRITE TOTAL (MG/L AS 0 0 0 0 0 0 N) .040 .030 .050 .100 .040 .070 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS 0 0 0 0 0 0 N) .390 .400 .500 .700 .300 .400 NITRO- GEN, AMMONIA TOTAL (MG/L AS 0. 0. 0. 0. 0. 0. N) 160 070 140 410 130 140 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0. 0. 0. 0. 0. 0. 44 33 46 59 37 36 RIO GRANDB DB LOZZA BASIN 50055000 RIO GRANDB DB LOZZA AT CAGOAS, PR—Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 225 DATE OCT 1992 09... DEC 14... FEB 1993 24... APR 16... •TON 17... AUG 12... DATE OCT 1992 09... DEC 14... FEB 1993 24.. . APR 16... JUN 17... AUG 12... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.60 0.40 0.60 1.0 0.50 0.50 IRON, TOTAL RECOV- ERABLE (UG/L AS FE) 750 -- -- 5800 -- -- NITRO- GEN, TOTAL (MG/L AS N) 0.99 0.80 1.1 1.7 0.80 0.90 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) 16 -- -- S -- -- NITRO- GEN, TOTAL (MG/L AS NO3) 4.4 3.5 4.9 7.5 3.5 4.0 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) 150 -_ -- 310 -- -- PHOS- PHORUS TOTAL (MG/L AS P) 0.200 0.090 0.020 0.310 0.140 0.200 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) <1 200 __ __ <1 100 __ — — — — SILVER, SELB- TOTAL NIUM, RECOV- TOTAL BRABLB (UG/L (UG/L AS SB) AS AG) <1 2 __ __ <1 <1 __ __ BORON, TOTAL RECOV- ERABLE (UG/L AS B) 30 -- -- 30 -- — — ZZNC, TOTAL RECOV- ERABLE (UG/L AS ZN) 10 __ __ 30 -- -- CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 -- — <1 — — — CYANIDE TOTAL (MG/L AS CN) •cO.010 — -- <0.010 -_ -- CHRO- MIUM, COPPER, TOTAL TOTAL RBCOV- RECOV- ERABLE BRABLB (UG/L (UG/L AS CR) AS CO) 14 <10 __ __ 7 20 __ — — — — MBTHY- LENB BLUB ACTIVE PHENOLS SUB- TOTAL STANCE (UG/L) (MG/L) 1 0.06 __ __ 1 0.04 __ __ 226 RIO GRANDS DE LOIZA BASIN 50055000 RIO GRANDS DB LOIZA AT CAGUAS, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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 93 90 84 82 80 362 235 108 94 91 90 87 80 78 77 78 78 93 94 88 174 164 88 91 204 139 86 79 79 86 77 27 20 14 11 9 202 139 82 48 43 37 32 26 21 21 25 29 46 89 82 106 94 48 49 109 87 47 33 33 35 39 6.8 4.8 3.2 2.4 1.9 621 114 25 12 11 9.0 7.6 5.7 4.5 4.4 5.1 5.9 13 23 19 87 53 11 16 71 35 11 6.9 7.1 8.0 8.2 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) NOVEMBER MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) DECEMBER 98 77 113 238 156 208 238 117 98 216 104 84 94 80 148 124 189 739 286 174 160 141 158 153 134 115 446 2200 410 1970 66 52 60 124 90 140 127 75 62 141 141 73 35 24 73 150 113 460 145 107 62 42 35 49 55 24 190 910 187 793 18 11 23 90 43 108 92 26 17 92 40 17 8.8 5.3 56 52 78 1970 132 52 26 16 15 23 21 7.6 556 11800 226 8920 559 324 284 232 188 163 147 133 126 121 115 109 106 262 205 117 109 105 103 98 100 130 113 103 112 1070 286 153 323 258 476 254 155 131 103 30 18 17 17 15 13 11 10 10 76 79 18 18 27 35 52 69 85 100 99 83 502 157 89 165 155 228 564 146 109 65 16 8.0 7.3 6.3 5.1 4.2 3.4 2.9 2.7 244 63 5.7 5.1 7.4 9.8 14 18 30 30 28 25 3810 143 38 160 110 404 TOTAL 3429 1213.5 9468 24541.7 6730 6084.9 RIO GRANDS DB LOIZA BASIN 50055000 RIO GRANDS DB LOIZA AT CAGUAS, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 227 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 518 282 232 196 166 180 232 222 176 157 137 137 126 138 120 114 111 107 115 99 92 102 157 101 175 125 116 144 350 146 113 5186 232 93 60 74 38 17 61 95 67 86 72 62 56 67 37 13 16 20 24 26 25 24 40 19 80 156 148 140 383 221 103 335 79 41 39 17 8.6 45 62 33 36 27 23 20 26 12 4.1 4.7 5.8 7.4 7.0 6.3 6.6 20 5.2 59 54 45 54 428 92 32 1634.7 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) FEBRUARY 99 99 115 92 87 84 84 80 79 75 78 90 108 82 74 71 73 74 69 70 71 68 66 69 64 64 66 60 ___ 2211 80 77 74 72 71 70 69 67 65 58 44 30 23 29 44 54 57 57 59 71 92 112 132 131 86 55 36 38 ___ ___ —— —— 22 22 24 19 16 16 15 15 14 12 9.4 7.2 6.3 6.4 8.9 11 11 11 11 14 18 21 24 24 15 9.3 6.3 6.1 ___ ___ ___ 394.9 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MARCH 60 61 57 52 53 52 50 49 48 52 49 49 53 52 52 e50 e62 e61 e?0 e66 e56 e46 e44 e47 e48 e54 e50 e43 e39 e37 e36 1598 46 54 61 64 64 63 60 51 49 44 43 43 43 46 48 53 75 95 92 77 57 41 32 28 29 30 31 31 32 33 33 7.5 8.7 9.1 9.0 9.0 8.8 8.0 6.7 6.4 6.1 5.6 5.4 5.9 6.5 6.7 e7.1 e!2 e!5 e!7 e!5 e8.6 e5.3 e3.8 e3.5 e3.8 e4.2 e4.1 e3.6 e3.4 e3.5 e3.1 222.4 e Estimated 228 RIO GRANDEE DE LOIZA BASIN 50055000 RIO GRANDEE DE LOIZA AT CAGUAS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEEN- 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 e35 34 38 35 32 33 33 33 70 70 49 50 64 98 277 117 84 57 64 52 69 51 49 55 45 52 101 66 388 308 ___ APRIL 34 45 50 49 46 43 42 54 53 43 39 37 47 108 136 114 102 94 85 75 98 81 44 33 30 37 60 44 229 156 MAY e3 4 4 4 4 3 3 4 10 8 5 5 11 30 265 38 24 15 15 11 18 11 5 5 3 5 17 8 848 160 - .0 .0 .9 .6 .0 .7 .8 .7 .2 .2 .1 .6 .0 .6 .7 .0 — 848 1150 343 149 111 186 121 90 343 252 124 97 81 1880 323 157 116 104 95 91 94 86 84 88 86 179 154 158 92 77 72 417 503 171 60 39 100 73 58 246 133 79 66 54 1020 106 62 60 55 51 48 44 42 41 39 37 78 90 86 36 22 17 2130 3300 191 25 12 54 26 14 303 106 27 18 12 12500 118 27 19 15 13 12 11 9.6 9.3 9.3 8.9 47 40 42 8.9 4.5 3.2 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) JUNE 72 72 64 59 57 54 51 54 64 77 86 61 74 451 363 312 99 111 3730 1600 337 563 263 199 146 126 111 103 103 160 15 14 14 17 25 38 58 83 98 101 98 71 56 205 170 192 45 78 1470 652 179 209 133 114 83 52 28 14 21 82 2.9 2.7 2.3 2.7 3.8 5.6 8.0 12 17 21 23 12 13 411 256 269 12 50 16400 4390 169 370 97 62 34 18 8.5 3.8 6.4 37 TOTAL 2509 1552.1 7831 19115.7 9622 22719.7 e Estimated RIO GRANDE DE LOIZA BASIN 50055000 RIO GRANDE DE LOIZA AT CAGUAS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 229 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 TOTAL YEAR 108 104 189 156 100 86 95 183 105 85 6490 954 368 264 215 415 207 169 151 139 131 1350 1710 1190 464 310 344 217 185 167 157 16808 76769 MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) JULY 44 33 74 69 23 14 62 100 66 56 1660 433 169 59 12 154 123 77 45 24 11 423 728 759 214 156 173 100 73 70 66 —— MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AUGUST 13 9.4 47 33 6.3 3.2 20 51 19 13 64100 1350 174 46 7.0 278 69 35 18 9.0 3.9 4960 4120 2430 285 133 169 60 36 31 28 78556.8 167723.3 148 139 130 120 120 117 110 115 107 115 112 115 97 93 96 1780 352 177 145 127 118 171 383 219 149 132 126 112 103 101 116 6045 46 30 16 11 9 9 8 8 10 10 10 11 13 13 25 759 217 51 20 17 13 64 622 581 442 333 242 169 111 66 36 —— 18 11 5. 3. 2. 2. 2. 2. 2. 3. 3. 3. 3. 3. 7. 5310 246 27 8. 5. 4. 37 689 352 178 118 84 51 32 18 11 7246. 8 4 9 8 6 6 7 1 2 4 3 1 1 0 9 2 1 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) SEPTEMBER 121 111 136 103 130 184 107 101 166 265 207 120 103 105 94 181 122 328 157 128 102 91 632 356 152 120 98 103 316 393 --- 5332 46 111 194 142 95 102 61 45 87 133 144 88 52 30 15 82 71 280 81 53 31 18 241 178 94 73 60 51 141 191 --- —— 15 35 68 41 38 63 18 13 43 120 85 29 15 8 4 44 24 907 38 18 8 4 1940 278 43 25 16 14 232 253 - 4440 .8 .0 .6 .4 -- .8 230 RIO GRANDE DE LOIZA BASIN 50055000 RIO GRANDE DE LOIZA AT CAGUAS, PR—Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT DATE DEC 1992 26. .. MAY 1993 14... JUN 19... JUL 07... 23... AUG 16... TIME 1911 0937 0336 1244 0032 1125 DIS- CHARGE, INST. CUBIC FEET PER SECOND 1630 3740 3470 11500 1560 4130 SEDI- MENT, SUS- PENDED (MG/L) 5830 3480 2510 2270 3270 2520 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 25700 35100 23500 70500 13800 28100 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM 49 44 44 43 39 44 SED. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM 58 54 44 52 43 50 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 66 63 62 59 52 62 DATE DEC 1992 26... MAY 1993 14... JUN 19... JUL 11... 23... AUG 16... SBD. SUSP. FALL DIAM. PERCENT FINER THAN .016 MM 77 77 74 72 69 73 SED. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM 88 83 86 82 84 81 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 95 92 96 96 89 96 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 98 93 99 99 — 98 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 99 93 99.7 99.6 99.1 99 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 100 100 100 99.8 99.4 99.5 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 100 100 100 100 99.6 100 RIO GRANDE DE LOIZA BASIN 50055000 RIO GRANDE DE LOIZA AT CAGOAS--Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT 231 DATE OCT 1992 06... NOV 18... 18... DEC 01.. . 26... FEB 1993 06... MAY 01.. . 01.. . 14... JON 14... 15... 19... 19.. . JUL 11.. . 11... 22... 22.. . 24.. . AUG 16... 16... TIME 1649 1651 1742 1615 1637 1115 0710 2220 1452 1234 2320 0036 0910 1031 1256 1850 2145 0850 0955 1811 STREAM- FLOW, INSTAN- TANEOUS (CFS) 1550 2430 2200 1610 4570 82 236 1550 2840 990 1530 2650 3860 8770 12310 5540 3970 2040 5060 1660 SEDI- MENT, SUS- PENDED (MG/L) 1520 1650 1540 387 2170 385 838 2200 1660 3180 625 341 1930 1310 1440 748 1710 442 3290 1140 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 6360 10820 9150 1680 26770 85 534 9210 12730 8500 2580 2440 20110 31020 47860 11190 18330 2430 44950 5110 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 99 99 96 99 96 99 100 36 97 95 98 98 77 98 96 86 96 95 24 90 232 RIO GRANDE DE LOIZA BASIN 50055100 RIO CAGUITAS NEAR AGUAS BUBNAS, PR LOCATION.--Lat 18«14'48", long 66°05'37", 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'). HATER-DISCHARGE RECORDS PERIOD OP RECORD.—February 1990 to current year. GAGE.—Hater-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. DISCHARGE, CUBIC PEST PER SECOND, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN PEB MAR APR MAY JUN JUL AUG SEP 1 5.9 5.9 2 5.8 5.7 3 5.7 7.7 4 5.5 15 5 5.8 8.8 6 e23 6.6 7 e8.4 6.0 8 7.0 5.6 9 6.5 5.7 10 7.1 7.8 11 6.5 5.7 12 6.1 5.3 13 5.9 5.2 14 5.7 5.1 15 5.6 5.2 16 5.5 4.8 17 5.6 8.1 18 7.7 19 19 6.5 8.1 20 7.1 6.3 21 6.0 5.7 22 6.4 13 23 8.0 7.9 24 6.6 6.8 25 6.2 6.1 26 5.8 5.7 27 5.7 51 28 5.6 46 29 5.9 13 30 5.6 65 31 6.1 TOTAL 210.8 367.8 MEAN 6.80 12.3 MAX 23 65 KIN 5.5 4.8 AC-PT 418 730 CPSM 1.28 2.31 IN. 1.48 2.58 STATISTICS OP MONTHLY MEAN MEAN 11.0 8.49 MAX 20.9 12.3 (WY) 1991 1993 KIN 5.30 5.76 (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 PLOW INSTANTANEOUS PEAK STAGE INSTANTANEOUS LOW PLOW ANNUAL RUNOFF (AC- FT) ANNUAL RUNOFF (CPSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 15 9.9 8.5 8.0 7.4 7.1 6.9 6.8 6.8 6.8 6.6 6.3 6.3 7.0 7.7 6.4 6.2 6.1 6.1 6.0 6.0 7.4 6.4 7.1 18 149 17 11 21 13 12 415.8 13.4 149 6.0 825 2.53 2.92 DATA 9.43 13.4 1993 5.59 1992 FOR 10 9.5 9.7 10 9.3 8.9 29 14 10 9.1 8.4 8.1 7.8 7.5 7.4 7.1 7.2 7.1 6.9 6.8 6.6 14 11 7.7 7.6 7.2 7.1 7.1 7.6 6.7 6.6 283.0 9.13 29 6.6 561 1.72 1.99 6.5 6.5 7.0 6.5 6.5 6.4 6.4 6.3 6.2 6.5 6.1 6.5 6.4 6.1 6.0 e7.4 6.9 6.5 6.4 6.5 6.1 5.7 5.5 5.4 5.3 5.4 5.3 5.1 ___ --- 173.4 6.19 7.4 5.1 344 1.17 1.22 FOR WATER YEARS 1990 11.0 16.7 1992 7.19 1991 5.48 8.00 1991 3.51 1990 5.2 5.3 5.0 5.1 5.3 5.4 5.4 5.3 5.3 5.2 5.2 5.2 5.1 5.0 5.0 5.8 5.6 5.4 6.0 5.2 4.9 4.9 5.5 5.2 5.0 .9 .8 .7 .6 .5 .5 159.5 5.15 6.0 4.5 316 .97 1.12 - 1993 6.00 8.87 1990 3.60 1992 1992 CALENDAR YEAR 2711.4 7.41 235 2.4 2.6 5380 1.40 19.03 8.7 4.3 2.9 Jan 5 May 10 Apr 24 .4 .5 .5 .4 .4 .4 .4 7.8 8.3 6.6 9.1 11 24 12 132 16 8.3 6.9 6.2 19 12 9.2 7.5 6.9 6.6 6.6 8.0 10 17 12 394.0 13.1 132 4.4 781 2.48 2.77 29 35 17 11 9.6 22 12 9.8 40 17 12 11 9.7 133 17 10 9.0 8.2 7.7 7.5 7.2 7.1 19 9.1 9.9 28 13 10 8.8 8.7 8.3 556.6 18.0 133 7.1 1100 3.39 3.91 8.2 8.0 7.8 7.5 7.3 7.1 7.0 7.7 7.5 7.4 6.8 6.4 6.3 6. 6. 6. 6. 6. 21 18 7.8 7.7 6.9 6.6 6.7 6.8 6.9 8.5 7.2 11 241.5 8.05 21 6.1 479 1.52 1.70 6.9 7.3 12 8.1 7.0 6.7 7.1 7.1 6.2 6.3 146 21 27 15 17 12 9.9 9.5 9.3 9.2 9.0 35 48 50 17 13 12 11 10 10 9.5 575.1 18.6 146 6.2 1140 3.50 4.04 9.8 10 10 10 10 10 10 11 11 10 10 10 10 10 12 61 13 9.7 8.9 8.2 8.2 11 11 8.5 8.2 8.0 7.7 7.6 7.5 7.5 7.3 347.1 11.2 61 7.3 688 2.11 2.44 7.1 7.0 6.9 7.6 8.5 13 7.7 7.0 6.9 7.3 7.1 6.9 6.8 6.8 7.1 9.2 7.2 92 12 15 8.5 7.6 11 8.0 7.4 7.6 7.3 10 13 8.4 --- 337.9 11.3 92 6.8 670 2.13 2.37 , BY WATER YEAR (WY) 6.41 13.1 1993 3.19 1992 FOR 1993 4062. 11. 149 4. 4. 2990 18. 4. 8060 2. 28. 16 7. 5. 7.91 18.0 1993 2.48 1990 WATER YEAR 5 1 Dec 26 4 Apr 1 4 Apr 1 Sep 18 28 Sep 18 3 Apr 7 10 51 3 3 4.86 8.05 1993 3.40 1991 8.41 18.6 1993 3.74 1990 WATER 8. 11. 6. 235 1. 1. 2990 18. 1. 5980 1. 21. 11 5. 3. 7.05 11.2 1993 5.14 1991 YEARS 1990 - 26 1 22 Jan 5 8 May 7 9 May 22 Sep 18 28 Sep 18 8 May 3 56 17 1 0 7.23 11.3 1993 5.01 1991 1993 1993 1992 1992 1990 1990 1993 1993 1990 e Estimated RIO GRANDB DB LOIZA BASIN 50055100 RIO CAGUITAS NEAR AGUAS BUBNAS, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORDS.— Water years 1990 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: February 1990 to September 1993. INSTRUMENTATION.-- DH-48 and automatic sediment sampler. EXTREMES FOR PERIOD OF DAILY RECORD.— SEDIMENT CONCENTRATION! Maximum daily mean, 1,690 mg/L July 11, 1993; Minimum daily mean, 2 mg/L Several days. SEDIMENT LOADS: Maximum daily mean, 3,730 tons (3,360 tonnes) Jan. 05, 1992; Minimum daily mean, 0.02 ton (0.03 tonne) Several days. 233 EXTREMES FOR WATER YEAR 1993.-- Water Year 1993 Suspended-sediment concentration (mg/L) maximum minimum Suspended-sediment discharge (tons per day) maximum minimum 1,690 (July 11) 2 (Aug. 29) 1,890 (Apr. 15) SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 .05 (Aug. 29) MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DAY (CFS) (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 5.9 5.8 5.7 5.5 5.8 e23 e8.4 7.0 6.5 7.1 6.5 6.1 5.9 5.7 5.6 5.5 5.6 7.7 6.5 7.1 6.0 6.4 8.0 6.6 6.2 5.8 5.7 5.6 5.9 5.6 6.1 12 13 14 15 15 327 176 93 33 27 55 37 26 22 20 18 17 34 32 45 27 20 46 30 28 25 21 15 11 10 26 .18 .20 .20 .22 .24 e78 e4.1 1.9 .59 .51 1.0 .59 .42 .34 .29 .26 .27 .97 .59 .96 .43 .34 1.8 .55 .45 .38 .32 .22 .18 .15 .46 NOVEMBER 5.9 5.7 7.7 15 8.8 6.6 6.0 5.6 5.7 7.8 5.7 5.3 5.2 5.1 5.2 4.8 8.1 19 8.1 6.3 5.7 13 7.9 6.8 6.1 5.7 51 46 13 65___ 53 53 65 151 63 30 29 27 21 57 20 18 17 16 23 22 44 335 174 50 46 155 51 42 28 19 755 743 95 814 ___ .86 .81 1.5 8.7 1.5 .55 .46 .40 .31 1.4 .30 .26 .25 .22 .32 .30 1.1 43 4.5 .85 .70 12 1.1 .75 .45 .29 304 228 4.0 441___ MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) DECEMBER 15 9.9 8.5 8.0 7.4 7.1 6.9 6.8 6.8 6.8 6.6 6.3 6.3 7.0 7.7 6.4 6.2 6.1 6.1 6.0 6.0 7.4 6.4 7.1 18 149 17 11 21 13 12 212 49 38 36 37 35 27 20 16 15 14 13 14 27 28 12 12 12 10 9 6 38 49 44 274 1270 158 54 341 97 46 11 1.4 .86 .80 .74 .65 .50 .36 .30 .27 .24 .22 .24 .65 .77 .21 .20 .19 .16 .15 .11 .84 .83 .88 36 1770 9.0 1.6 41 4.0 1.5 TOTAL 210.8 97.11 367.8 1059.88 415.8 1885.67 e Estimated 234 RIO GRANDS DB LOIZA BASIN 50055100 RIO CAGUITAS NEAR AQUAS BUBNAS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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) 10 9.5 9.7 10 9.3 8.9 29 14 10 9.1 8.4 8.1 7.8 7.5 7.4 7.1 7.2 7.1 6.9 6.8 6.6 14 11 7.7 7.6 7.2 7.1 7.1 7.6 6.7 6.6 MEAN CONCEN- TRATION (MG/L) JANUARY 25 14 23 72 37 46 714 113 40 17 17 17 16 13 8 8 10 12 15 18 20 152 116 27 18 19 19 18 16 17 19 SEDIMENT DISCHARGE (TONS/DAY) .71 .35 .75 2.1 .99 1.1 153 4.8 1.2 .41 .39 .36 .33 .26 .17 .16 .20 .23 .28 .33 .35 13 4.2 .57 .37 .36 .35 .33 .33 .31 .32 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) 6.5 6.5 7.0 6.5 6.5 6.4 6.4 6.3 6.2 6.5 6.1 6.5 6.4 6.1 6.0 e7.4 6.9 6.5 6.4 6.5 6.1 5.7 5.5 5.4 5.3 5.4 5.3 5.1 FEBRUARY 20 20 17 13 10 7 7 6 5 19 18 16 20 23 24 19 16 13 10 8 8 10 12 12 11 11 9 7 283.0 188.61 173.4 .33 .33 .31 .23 .17 .13 .12 .11 .09 .38 .29 .28 .34 .37 .38 >.37 .29 .23 .17 .14 .14 .15 .17 .17 .16 .15 .13 .10 6.23 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MARCH 5.2 5.3 5.0 5.1 5.3 5.4 5.4 5.3 5.3 5.2 5.2 5.2 5.1 5.0 5.0 5.8 5.6 5.4 6.0 5.2 4.9 4.9 5.5 5.2 5.0 4.9 4.8 4.7 4.6 4.5 4.5 159.5 6 6 8 14 14 8 6 6 7 8 8 6 5 5 6 7 6 6 54 33 34 33 28 19 16 13 10 8 12 27 27 .08 .09 .12 .20 .20 .11 .08 .09 .11 .12 .11 .09 .07 .07 .08 .11 .10 .09 .97 .45 .44 .41 .37 .28 .21 .16 .12 .10 .15 .33 .33 6.24 e Estimated RIO GRANDB DB LOIZA BASIN 235 50055100 RIO CAGUITAS NEAR AGDAS BUENAS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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 .4 .5 .5 .4 .4 .4 .4 7.8 8.3 6.6 9.1 11 24 12 132 16 8.3 6.9 6.2 19 12 9.2 7.5 6.9 6.6 6.6 8.0 10 17 12 MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) APRIL 30 30 30 30 30 30 30 52 55 33 56 181 516 470 1400 181 67 79 70 279 96 63 47 35 27 26 33 61 470 87 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MAY .36 .36 .36 .36 .36 .36 .36 1.9 1.7 .61 2.2 7.3 87 15 1890 11 1.5 1.5 1.2 43 3.9 1.7 .96 .65 .48 .47 .82 3.4 46 3.0 29 35 17 11 9.6 22 12 9.8 40 17 12 11 9.7 133 17 10 9.0 8.2 7.7 7.5 7.2 7.1 19 9.1 9.9 28 13 10 8.8 8.7 8.3 673 615 139 48 20 429 83 55 626 162 86 59 51 1440 129 25 5 4 5 15 31 34 262 53 52 404 81 16 3 3 5 89 104 7.5 1.5 .51 65 3.0 1.5 120 8.5 2.9 1.7 1.3 1450 7.0 .76 .14 .09 .11 .30 .60 .65 43 1.3 1.4 104 3.2 .48 .07 .07 .13 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) JUNE 8.2 8.0 7.8 7.5 7.3 7.1 7.0 7.7 7.5 7.4 6.8 6.4 6.3 6.4 6.4 6.4 6.1 6.1 21 18 7.8 7.7 6.9 6.6 6.7 6.8 6.9 8.5 7.2 11___ 8 10 10 11 17 25 30 27 21 16 13 11 13 21 29 26 22 22 281 170 13 11 10 10 11 12 12 33 33 108 .18 .21 .21 .22 .33 .48 .55 .54 .41 .31 .23 .19 .21 .36 .51 .46 .35 .36 26 18 .28 .22 .19 .18 .20 .22 .22 1.1 .67 4.8 TOTAL 394.0 2127.81 556.6 2019.71 241.5 58.19 236 RIO GRANDB DE LOIZA BASIN 50055100 RIO CAGUITAS NEAR AGDAS BUBNAS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1992 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 15 16 17 18 19 20 21 22 23 24 2S 26 27 28 29 30 31 TOTAL YEAR 6.9 7.3 12 8.1 7.0 6.7 7.1 7.1 6.2 6.3 146 21 27 15 17 12 9.9 9.5 9.3 9.2 9.0 35 48 50 17 13 12 11 10 10 9.5 575.1 4062.5 JULY 27 68 113 32 15 9 29 37 30 28 1690 329 788 151 108 30 26 22 21 21 16 602 626 662 26 18 IS 14 14 IS 14 —— MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AUGUST .51 1.9 6.2 .74 .27 .16 .67 .71 .50 .50 1290 27 76 7.5 13 .98 .69 .55 .53 .51 .38 176 119 197 1.3 .66 .47 .42 .39 .38 .34 1925.26 10788.80 9.8 10 10 10 10 10 10 11 11 10 10 10 10 10 12 61 13 9.7 8.9 8.2 8.2 11 11 8.5 8.2 8.0 7.7 7.6 7.5 7.5 7.3 347.1 11 10 9 8 8 8 8 7 6 4 3 3 3 3 3 797 82 23 25 25 23 56 72 27 8 6 6 4 2 4 8 —— .28 .25 .24 .23 .22 .22 .22 .21 .17 .11 .08 .08 .08 .08 .10 197 3.3 .58 .57 .56 .50 2.2 2.3 .64 .17 .14 .14 .08 .05 .08 .16 211.04 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) SEPTEMBER 7.1 7.0 6.9 7.6 8.5 13 7.7 7.0 6.9 7.3 7.1 6.9 6.8 6.8 7.1 9.2 7.2 92 12 15 8.5 7.6 11 8.0 7.4 7.6 7.3 10 13 8.4 --- 337.9 11 12 12 40 49 152 143 102 75 54 36 23 13 7 10 66 30 661 104 449 40 20 55 40 32 32 30 75 160 42 —— .20 .21 .22 .95 2.0 14 3.2 1.9 1.4 1.0 .73 .43 .24 .14 .25 2.1 .57 1080 4.0 67 .98 .42 4.7 .92 .64 .65 .60 3.5 9.1 1.0 --- 1203.05 DATE APR 1993 15... 29... MAY 01... 06. .. 26... JUL 22... RIO GRANDB DB LOIZA BASIN 50055100 RIO CAGUITAS NEAR AQUAS BUENAS, PR—Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1992 TO SBPTBMBBR 1993 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT 237 TIME 1920 1800 1720 1900 1453 DIS- CHARGE, INST. CUBIC FEET PER SECOND 109 28 81 65 213 SEDI- MENT, SUS- PENDED (MG/L) 3760 13000 3170 2930 4480 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 1110 970 693 514 2580 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM 53 26 53 57 30 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM 59 31 63 68 38 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 66 35 67 69 45 1845 176 4020 1910 43 51 58 DATE APR 1993 15... 29.. . MAY 01... 06... 26... JUL 22... SBD. SUSP. FALL DIAM. PERCENT FINER THAN .016 MM 75 42 76 82 55 70 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM 82 56 82 83 66 78 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 94 75 93 98 78 94 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 98 90 96 99 88 99 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 99 97 98 99.6 96 98.8 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 99.8 99.4 99 100 99 99.5 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 100 99.8 100 100 99.8 100 23d RIO GRANDE DE LOIZA BASIN 50055100 RIO CAGUITAS NEAR AQUAS BUBNAS, PR--Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT DATE OCT 1992 16... NOV 25... DEC 01... JAN 1993 07... APR 12.. . 29... 30... MAY 01... 06.. . 26.. . JUL 13... 22... SEP 29.. . TIME 1205 1455 1942 1832 1755 2125 1140 1555 1745 1625 2305 2300 1015 STREAM- FLOW, INSTAN- TANEOUS (CPS) 5.5 6.1 22 83 13 22 11 56 12 84 27 26 9.9 SEDI- MENT, SUS- PENDED (MG/L) 308 145 3820 2970 651 1510 161 2400 2590 1660 728 1050 419 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 4.6 2.4 227 666 23 90 4.8 363 84 376 53 74 11 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 98 99 94 97 93 96 81 86 92 95 97 98 97 RIO GRANDE DE LOIZA BASIN 239 50055170 RIO CAGUITAS NEAR CAGUAS, PR LOCATION.--Lat 18°13'59", long 66°02'53", Hydrologic Unit 21010005, on left bank, 0.9 mi (1.4 km) southwest from Plaza de Caguas, 0.6 mi (1.0 km) northeast from Bscuela Bunker, and 1.2 mi (1.9 km) northwest from Bscuela Antonio S. Pedreira. DRAINAGE AREA.--8.27 mi 1 (21.42 km1 ). HATER-DISCHARGE RECORDS PERIOD OF RECORD.--May 1992 to current year. GAGE.--Hater-stage recorder and crest-stage gage. Elevation of gage is 216 ft (66 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 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 TOTAL MEAN MAX MIN AC -FT CPSM IN. STATISTICS OF MONTHLY MEAN DATA FOR HATER YEARS 1992 - 1992, MEAN MAX (HY) MIN (HY) e!6 7.5 6.4 9.3 38 13 6.2 9.8 8.3 12 88 143 44 25 14 elO e8.2 e7.6 e7.2 ___ ___ ___ ___ ___ ___ --- BY HATER YEAR (HY) ___ ___ ___ ___ ___ e7.0 e6.6 e6.6 e6.4 e7.0 e6.2 e6.0 e8.6 e8.0 e!5 9.5 13 14 7.9 7.1 11 6.1 6.1 5.3 4.5 6.7 5.6 4.8 5.0 e5.4 e5.4 e5.2 e5.6 e5.8 e5.8 --- 217.2 7.24 15 4.5 431 .88 .98 7.24 7.24 1992 7.24 1992 e5.1 e5.6 e5.2 e5.6 e5.6 e6.4 e5.4 e5.4 e6.4 e5.8 e5.4 e6.8 e5.4 e5.0 e4.9 e5.4 e7.4 ell e7.2 e6.0 e5.6 e7.8 ell e6.8 e8.0 elO e6.8 e6.8 e5.4 e4.8 e5.0 199.0 6.42 11 4.8 395 .78 .90 6.42 6.42 1992 6.42 1992 e5.0 e5.2 e5.8 e8.0 e25 e!20 e!6 e8.2 e7.0 e6.2 e5.8 e6.0 e6.2 e5.6 e6.0 e5.4 e5.0 e4.9 e4.8 e4.6 e4.6 e4.6 e4.7 e5.0 e4.8 e4.5 5.0 5.0 5.0 5.2 6.6 315.7 10.2 120 4.5 626 1.23 1.42 10.2 10.2 1992 10.2 1992 4.8 4.5 5.1 5.4 17 13 8.5 7.5 21 6.5 5.4 4.9 4.8 5.3 6.8 13 11 7.8 131 111 75 117 48 17 12 9.5 8.8 8.4 7.8 8.0 --- 705.8 23.5 131 4.5 1400 2.84 3.17 23.5 23.5 1992 23.5 1992 Estimated 240 RIO GRANDB DB LOIZA BASIN 50055170 RIO CAGUITAS NEAR CAGUAS, PR--Continued DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES NOV JAN FBB APR MAY JUN JUL AUG SEP 1 9.0 8.3 2 8.5 6.6 3 8.1 32 4 7.9 51 5 6.8 23 6 106 11 7 44 8.5 8 14 7.5 9 11 7.8 10 26 32 11 14 8.4 12 8.9 6.8 13 7.3 6.4 14 6.7 5.9 15 6.6 6.1 16 6.0 6.2 17 6.0 42 18 e28 88 19 e!2 25 20 e8.3 11 21 e7.0 9.0 22 7.6 23 23 7.3 15 24 9.3 9.9 25 7.5 8.0 26 6.2 7.5 27 5.9 147 28 5.4 239 29 6.7 44 30 6.1 227 31 5.7 - — TOTAL 419.8 1122.9 MEAN 13.5 37.4 MAX 106 239 MXN 5.4 5.9 AC-PT 833 2230 CFSM 1.64 4.53 IN. 1.89 5.05 57 27 17 16 12 12 9.9 9.3 9.1 8.8 8.6 8.0 7.7 37 20 9.5 9.3 8.5 8.2 8.1 7.5 17 9.5 11 40 401 103 32 115 52 56 1147.0 37.0 401 7.5 2280 4.47 5.16 STATISTICS OP MONTHLY MEAN DATA MEAN 13.5 37.4 MAX 13.5 37.4 (WY) 1993 1993 MIN 13.5 37.4 (WY) 1993 1993 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 37.0 37.0 1993 37.0 1993 22 20 18 18 18 16 106 44 21 19 18 17 16 15 14 14 13 13 13 12 12 27 37 14 13 13 12 12 12 11 11 621 20.0 106 11 1230 2.42 2.79 POR WATER 20.0 20.0 1993 20.0 1993 11 11 13 10 10 9.7 9.7 9.5 9.3 9.1 9.4 9.4 9.8 8.6 8.5 12 12 8.8 8.4 8.2 8.6 8.5 8.3 7.4 6.9 7.0 6.7 6.7 ___ ___ --- 7.8 7.6 6.9 6.8 6.6 6.0 6.4 6.5 6.7 6.3 5.8 5.4 5.9 6.0 5.6 6.3 6.7 6.5 6.4 6.1 5.5 5.6 6.1 6.6 6.2 6.4 6.2 5.7 6.0 5.9 5.6 257.5 194.1 9.20 13 6.7 511 1.11 1.16 YEARS 1992 - 9.20 9.20 1993 9.20 1993 FOR 1993 8955. 24. 447 5. 5. 3010 26. 17760 2. 40. 44 12 6. 6.26 7.8 5.4 385 .76 .87 1993 6.26 6.26 1993 6.26 1993 5.6 5.5 5.9 5.8 6.1 6.2 6.3 11 18 13 12 18 43 17 251 53 19 14 12 50 25 19 13 13 12 16 25 21 86 33 835.4 27.8 251 5.5 1660 3.37 3.76 , BY WATER 27.8 27.8 1993 27.8 1993 94 130 43 20 18 68 31 18 111 41 22 18 16 307 32 18 15 13 13 13 12 12 49 16 14 57 22 16 13 13 12 1277 41.2 307 12 2530 4.98 5.74 YEAR (WY) 41.2 41.2 1993 41.2 1993 11 11 10 9.9 9.9 9.0 8.9 9.9 9.7 10 9.8 9.7 9.8 12 13 11 9.5 11 80 57 16 16 12 11 11 10 9.8 12 12 15 446.9 14.9 80 8.9 886 1.80 2.01 11.1 14.9 1993 7.24 1992 WATER YEAR 9 5 4 7 10 97 29 4 Jul 11 Oct 28 Mar 28 Sep 18 Sep 18 11 11 15 11 9.5 9.2 14 11 8.8 8.4 447 56 67 32 31 22 16 15 17 16 16 111 163 139 38 25 21 18 17 17 17 1409.9 45.5 447 8.4 2800 5.50 6.34 25.9 45.5 1993 6.42 1992 HATER 24 24 24 447 4 4 3010 26 17780 2 40 40 11 5 16 15 15 15 15 14 14 14 13 14 14 13 13 13 15 168 24 16 14 13 13 36 24 15 14 13 13 12 13 12 12 625 20.2 168 12 1240 2.44 2.81 15.2 20.2 1993 10.2 1992 YEARS 1992 .5 .5 .5 Jul .5 Jun .7 Aug Sep . 10 Sep .97 .31 .6 11 11 11 13 17 22 14 12 11 11 11 9.2 10 9.9 11 15 11 204 25 20 11 9.5 16 13 9.4 11 9.4 20 27 14--- 599.4 20.0 204 9.2 1190 2.42 2.70 21.8 23.5 1992 20.0 1993 - 1993 1993 1993 11 1993 20 1992 20 1992 18 1993 18 1993 e Estimated RIO GRANDB DB LOIZA BASIN 50055225 RIO CAGUITAS AT VILLA BLANCA AT CAGUAS, PR 241 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 Orande de Loiza, and 0.95 mi (1.53 km) northeast from Caguas Plaza. DRAINAGE AREA.--11.71 mi 1 (30.33 km 1 ). HATER-DISCHARGE RECORDS PERIOD OF RECORD.—December 1990 to current year. GAGE.—Hater-stage recorder. Elevation of gage is 164 ft (50 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 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 17 18 2 17 13 3 17 76 4 18 59 5 15 34 6 251 25 7 90 20 8 27 18 9 24 17 10 48 76 11 28 21 12 19 16 13 15 16 14 18 15 15 15 17 16 14 14 17 14 61 18 48 84 19 25 34 20 16 21 21 11 23 22 16 29 23 10 26 24 17 24 25 14 19 26 9.8 17 27 7.5 159 28 5.8 398 29 12 53 30 8.5 300 31 8.9 - — TOTAL 856.5 1703 MEAN 27.6 56.8 MAX 251 398 MIN 5.8 13 MED 16 23 AC-FT 1700 3380 CFSM 2.36 4.85 IN. 2.72 5.41 STATISTICS OF MONTHLY MEAN MEAN 23.8 45.6 MAX 27.6 56.8 (WY) 1993 1993 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 54 37 29 31 25 26 22 20 18 18 17 17 16 42 34 20 23 21 20 21 17 34 25 27 41 876 61 37 81 48 51 1809 58.4 876 16 26 3590 4.98 5.75 DATA 37.8 58.4 1993 17.2 1992 FOR 34 34 30 30 29 27 85 43 30 28 28 29 27 25 26 25 25 25 24 25 25 44 42 28 27 27 26 25 26 24 23 946 30.5 85 23 27 1880 2.61 3.01 FOR HATER 56.9 120 1992 20.3 1991 23 22 30 23 25 25 24 23 22 21 21 22 22 18 17 24 23 17 17 16 17 16 15 15 13 15 15 13 ___ 554 19.8 30 13 21 1100 1.69 1.76 YEARS 1991 18.0 23.8 1991 10.8 1992 16 17 15 14 14 13 13 12 11 11 10 9.5 9.8 10 9.9 15 16 15 13 13 10 10 12 13 11 11 10 8.7 7.9 7.4 7.5 365.7 11.8 17 7.4 11 725 1.01 1.16 - 1993 12.0 15.3 1991 8.76 1992 1992 CALENDAR YEAR 13220. 36. 1930 5. 6. 26220 3. 42. 44 15 8. 3 1 Jan 5 8 Oct 28 9 Mar 7 08 00 1 7.3 6.2 6.6 6.0 6.5 6.4 9.4 16 23 18 19 25 40 31 473 49 25 17 14 46 32 25 17 15 13 28 38 34 98 50 1194.4 39.8 473 6.0 21 2370 3.40 3.79 93 106 45 29 27 51 35 26 80 39 31 26 24 597 57 39 33 31 30 33 27 25 57 33 33 78 50 35 30 28 26 1854 59.8 597 24 33 3680 5.11 5.89 27 24 22 20 17 16 15 15 17 18 16 17 20 35 41 25 18 27 151 75 34 44 31 28 26 24 22 26 33 38 922 30.7 151 15 24 1830 2.62 2.93 26 30 36 28 23 21 37 33 20 21 851 71 88 51 48 41 31 e28 e28 e30 e27 e!81 e!68 e!30 eS4 e45 e38 e34 e32 e31 e30 2312 74.6 851 20 33 4590 6.37 7.34 e29 e27 e27 e26 e25 e26 e25 e26 e24 e24 e25 e21 e21 e23 e28 e210 e38 e28 e27 e27 e25 e75 e48 e29 e28 e25 e25 e24 e24 e24 e23 1057 34.1 210 21 26 2100 2.91 3.36 e22 e22 e21 e25 e27 e42 e26 e24 e24 e26 e23 e22 e22 e22 e25 e31 e25 e273 e40 e48 e27 e24 e35 e25 e24 e25 e23 e34 e42 e27 --- 1076 35.9 273 21 25 2130 3.06 3.42 , BY HATER YEAR (WY) 20.7 39.8 1993 9.81 1992 FOR 1993 14649 40 876 5 6 5860 16 29060 3 46 53 25 13 35.8 59.8 1993 17.2 1991 WATER YEAR .6 .1 Dec 26 .8 Oct 28 .6 Mar 31 Dec 26 .23 Dec 26 .43 .54 19.4 30.7 1993 10.5 1991 37.3 74.6 1993 11.7 1992 WATER 35 40 30 1930 5 5 13400 19 25460 3 40 42 16 7 28.0 36.1 1992 13.8 1991 YEARS 1991 - .1 .1 .2 Jan 5 .6 Jun 29 . 9 Aug 3 Jan 5 .91 Jan 5 .00 .78 .8 32.2 44.2 1992 16.4 1991 1993 1993 1992 1992 1991 1991 1992 1992 e Estimated 242 RIO GRANDE 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. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE! December 1990 to September 1993. INSTRUMENTATION.-- DH-48 and automatic sediment sampler. EXTREMES FOR PERIOD OP DAILY RECORD.-- SEDIMENT CONCENTRATION! Maximum daily mean, 1,430 mg/L Jan. 05, 1992; Minimum daily mean, 1 mg/L Oct. 01, 1992. SEDIMENT LOADS: Maximum daily mean, 8,820 tons (8,000 tonnes) Jan. 05, 1992; Minimum daily mean, 0.08 ton (0.07 tonne) several days. EXTREMES FOR WATER YEAR 1993.-- Water Year 1993 Suspended-sediment concentration (mg/L) maximum minimum Suspended-sediment discharge (tons per day) maximum minimum 1,350 (Hay 14) 1 (Oct. 01, 1992) 2,900 (July 11) SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) NOVEMBER .08 (Several days) MEAN MEAN CONCBN- SEDIMENT MEAN DISCHARGE TRATION DISCHARGE DISCHARGE DAY (CPS) (MG/L) (TONS/DAY) (CPS) 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 17 17 17 18 15 251 90 27 24 48 28 19 15 18 15 14 14 48 25 16 11 16 10 17 14 9.8 7.5 5.8 12 8.5 8.9 1 14 9 8 7 419 257 47 81 188 224 203 184 142 101 77 50 133 64 30 24 45 33 29 42 39 34 29 31 20 17 1.0 .62 .42 .38 .29 829 200 3.7 6.3 54 17 11 7.5 6.9 3.9 2.9 1.9 56 4.9 1.3 .74 2.3 .93 1.4 1.6 1.0 .72 .45 1.3 .46 .42 18 13 76 59 34 25 20 18 17 76 21 16 16 15 17 14 61 84 34 21 23 29 26 24 19 17 159 398 53 300 ___ 18 13 76 59 34 25 20 18 17 76 21 16 16 15 17 14 61 84 34 21 23 29 26 24 19 17 159 398 53 300 38 29 265 108 54 141 213 185 166 215 38 29 26 24 118 210 328 215 199 163 97 50 50 43 36 31 516 533 115 764 3.2 1.1 165 19 5.4 9.6 11 8.8 7.8 84 2.2 1.3 1.1 .94 6.4 7.7 82 84 19 9.1 5.9 4.5 3.9 2.9 1.8 1.4 615 1170 20 1000 MEAN DISCHARGE (CPS) 54 37 29 31 25 26 22 20 18 18 17 17 16 42 34 20 23 21 20 21 17 34 25 27 41 876 61 37 81 48 51 MEAN CONCEN- TRATION (MG/L) DECEMBER 96 64 45 47 36 21 23 27 31 30 28 27 23 81 84 44 27 20 38 95 107 71 39 46 70 494 114 31 164 65 88 SEDIMENT DISCHARGE (TONS/ DAY) 16 6.8 3.6 4.3 2.5 1.5 1.4 1.5 1.5 1.4 1.3 1.2 .97 26 9.4 2.4 1.7 1.3 2.1 5.9 4.9 7.8 2.7 3.5 10 2630 24 3.1 50 10 15 TOTAL 856.5 1220.33 1703 3354.04 1809 2853.77 RIO GRANDS DB LOIZA BASIN 243 50055225 RIO CAGUITAS AT VILLA BLANCA AT CA6DAS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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 34 34 30 30 29 27 85 43 30 28 28 29 27 25 26 25 25 25 24 25 25 44 42 28 27 27 26 25 26 24 23 45 33 14 12 12 12 395 76 53 38 27 18 14 10 11 14 14 16 19 21 26 75 72 41 40 40 39 38 181 184 141 4.1 3.2 1.1 .96 .94 .88 245 9.6 4.3 2.9 2.1 1.4 1.0 .69 .81 .95 .98 1.1 1.2 1.4 1.8 13 9.0 3.2 2.9 2.9 2.7 2.6 13 12 8.6 FEBRUARY 23 22 30 23 25 25 24 23 22 21 21 22 22 18 17 24 23 17 17 16 17 16 15 15 13 15 15 13 ___ ___ ___ 91 33 54 32 19 18 18 17 15 15 15 22 31 41 46 56 29 15 9 12 17 20 25 34 47 58 63 68 ___ ___ ___ 5.6 1.9 4.9 2.0 1.3 1.2 1.1 1.1 .92 .82 .81 1.3 1.8 2.0 2.1 4.2 1.8 .69 .43 .50 .75 .87 .99 1.4 1.7 2.3 2.6 2.4 ___ ___ MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MARCH 16 17 15 14 14 13 13 12 11 11 10 9.5 9.8 10 9.9 15 16 15 13 13 10 10 12 13 11 11 10 8.7 7.9 7.4 7.5 49 18 19 18 18 18 19 29 42 47 18 16 23 23 21 20 19 17 18 25 35 42 30 16 8 6 6 5 4 4 5 2.0 .83 .77 .69 .66 .63 .69 .94 1.2 1.4 .51 .41 .60 .64 .56 .81 .81 .71 .63 .86 .93 1.2 .99 .56 .25 .18 .18 .13 .08 .08 .11 TOTAL 946 356.31 554 49.48 365.7 21.04 244 RIO GRANDS DE LOIZA BASIN 50055225 RIO CAGUITAS AT VILLA BLANCA AT CAGUAS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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 7.3 6.2 6.6 6.0 6.5 6.4 9.4 16 23 18 19 25 40 31 473 49 25 17 14 46 32 25 17 15 13 28 38 34 98 50 APRIL 23 18 8 8 10 10 17 28 33 29 32 17 47 45 406 79 41 29 12 77 59 42 32 28 23 73 94 76 320 89 .46 .31 .15 .13 .17 .17 .93 2.3 2.5 1.5 2.5 1.2 10 4.0 1540 13 2.7 1.4 .44 21 5.7 2.8 1.5 1.2 .82 26 23 13 267 17 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MAY MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) JUNE 93 106 45 29 27 51 35 26 80 39 31 26 24 597 57 39 33 31 30 33 27 25 57 33 33 78 50 35 30 28 26 263 228 111 77 55 130 257 152 255 190 167 142 106 1350 64 40 40 40 41 59 42 35 116 57 58 151 92 53 25 12 11 139 91 14 6 4 27 25 11 63 20 14 10 6 2270 11 4 3 3 3 5 3 2 40 5 5 64 14 5 2 .0 .2 .9 .2 .6 .4 .3 .7 .1 .4 .1 .5 .1 .0 .86 .74 27 24 22 20 17 16 15 15 17 18 16 17 20 35 41 25 18 27 151 75 34 44 31 28 26 24 22 26 33 38 10 16 20 24 23 20 17 16 15 13 12 11 23 63 98 169 150 138 373 143 34 71 44 52 65 72 51 45 57 61 .80 1.0 1.2 1.3 1.0 .85 .65 .64 .68 .60 .52 .48 2.1 9.7 15 12 7.3 18 212 43 3.2 9.4 3.7 3.8 4.5 4.7 3.0 3.3 5.6 6.6 TOTAL 1194.4 1962.88 1854 2875.10 922 376.62 RIO QRANDE DB LOI2A BASIN 245 50055225 RIO CAGOITAS AT VILLA BLANCA AT CAGUAS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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) (MQ/L) (TONS/ DAY) 26 30 36 28 23 21 37 33 20 21 851 71 88 51 48 41 31 628 628 630 627 el81 6168 6130 654 645 638 634 632 631 630 JULY 43 57 61 47 27 14 52 88 38 38 856 92 171 89 80 74 57 53 54 56 58 353 532 378 66 80 27 11 11 11 39 TOTAL 2312 — - YEAR e 14649.6 Estimated 3.1 5.0 6.4 3.6 1.7 .76 9.4 9.2 2.0 2.4 2900 22 85 14 13 8.7 4.7 e4.0 e4.0 e4.5 e4.3 e514 6380 e254 ell elO e2.8 el.O e.90 e.92 63.1 4285.48 19072.25 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) AUGUST MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) e29 e27 e27 e26 e25 e26 e25 e26 e24 e24 e25 621 621 e23 628 e210 e38 e28 627 627 e25 e75 648 e29 e28 e25 e25 e24 e24 e24 623 79 114 103 78 55 48 50 58 58 49 72 71 90 98 72 714 63 47 45 44 42 205 84 50 49 52 42 43 46 53 58 66.1 68.5 e7.4 e5.5 e3.7 e3.4 63.4 64.1 e3.7 63.1 65. 1 64.0 65. 1 e6.2 e7.7 e534 66.6 63.6 63.3 63.1 62.8 e!09 e!2 e4.0 e4.0 e3.8 e2.8 e2.8 e3.0 e3.4 e3.6 SEPTEMBER 1057 778.8 622 622 621 625 627 642 e26 e24 e24 e26 e23 e22 e22 622 e25 e31 625 e273 e40 648 627 624 635 e25 624 625 623 634 642 e27 1076 75 39 38 42 44 66 43 41 41 37 20 25 31 41 55 65 42 383 98 53 35 21 35 42 41 42 40 55 69 45 e4.4 e2.3 e2.2 62.8 63.2 e7.5 63.0 e2.5 e2.7 e3.0 el. 3 el. 5 el. 8 e2.4 e3.7 e5.4 e2.8 e834 ell e6.8 e2.6 el. 3 e3.3 e2.8 e2.7 e2.8 e2.5 e5. 0 e7.8 e3.3 938.4 246 RIO GRANDB DB LOIZA BASIN 50055225 RIO CAGUITAS AT VILLA BLANCA AT CAGUAS, PR--Continued HATER QUALITY DATA, HATER YEAR JULY 1992 TO SEPTEMBER 1993 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT DATE NOV 1992 27... DEC 26. .. APR 15... DIS- CHARGE, INST. CUBIC FEET TIME PER SECOND 1752 729 1527 5690 1715 4460 SEDI- MENT, SUS- PENDED (MG/L) 2770 1220 4620 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 5450 18700 55600 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM 46 67 48 SED. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM 62 74 57 SED. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 76 82 74 DATE NOV 1992 27... DEC 26... APR 1993 15.. . SBD. SUSP. FALL DIAM. PERCENT FINER THAN .016 MM 84 85 86 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM 89 87 90 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 99 97 98.7 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 99.2 98.2 99 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 99.6 98.7 99.5 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 99.8 99 99.7 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 100 99.5 99.8 RIO GRANDB DB LOIZA BASIN 50055225 RIO CAGUITAS AT VILLA BLANCA AT CAGUAS, PR--Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT 247 DATE OCT 1992 06... 06... NOV 25.. . 21... 27... DEC 26.. . 26... JAN 1993 07.. . APR 29... HAY 14... JDN 29... AUQ 08.. . 17... 26... TIME 1452 2037 1430 1722 2107 1412 1842 1552 1645 1500 1525 1640 1600 1000 STREAM- FLOW, INSTAN- TANEOUS (CFS) 908 558 19 559 344 2140 680 291 538 25 36 25 34 25 SEDI- MENT, SUS- PENDED (MG/L) 1200 1040 500 1780 1600 654 556 1790 2250 8290 4790 801 1320 7590 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 2940 1570 26 2690 1490 3790 1020 1410 3270 560 466 54 122 512 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 89 96 81 97 99 99 99 87 91 88 99 94 98 12 RIO GRANDB DE LOIZA BASIN 50055250 RIO CAGUITAS AT HIGHWAY 30 AT CAGUAS, 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 km2 ). PERIOD OP RECORD.—Water years 1972 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 14... DEC 04... FEB 1993 10. .. APR 12... MAY 25. .. AUG 05. .. TIME 1145 1050 1210 1245 1300 0930 DIS- CHARGE, INST. CUBIC FEET PER SECOND 39 38 26 28 27 62 SPE- CIFIC CON- DUCT- ANCE (US/CM) 598 500 400 650 300 555 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.3 7.0 7.0 6.3 7.4 6.8 TEMPER- ATURE WATER (DBG C) 29.0 26.1 26.0 28.0 28.0 27.5 TUR- BID- ITY (NTU) 5.0 8.2 7.4 2.4 4.5 26 OXYGEN, DIS- SOLVED (MG/L) 3.0 2.8 2.9 1.4 3.7 4.6 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 38 34 22 18 48 53 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 51 49 59 50 56 55 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 52000 220000 210000 57000 K65000 35000 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 3400 2700 29000 20000 K1600 20000 DATE OCT 1992 14. .. DEC 04. .. FBB 1993 10... APR 12... MAY 25... AUG 05... HARD- NESS TOTAL (MG/L AS CACO3) HARD- NESS NONCARB WH WAT TOT FLD 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) 120 16 39 15 30 130 4 35 11 32 150 9 39 13 33 ALKA- SODIUM POTAS- LINITY CHLO- AD- SIUM, WAT WH SULFATE 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) 4.3 6.1 1 4.8 CACO3 160 100 120 79 150 100 AS S) AS SO4) AS CL) <0.5 36 <0.5 39 38 30 41 36 SOLIDS, RESIDUE DATE OCT 1992 14... DEC 04... FBB 1993 10... APR 12... MAY 25... AUG 05... FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.20 -- -- 0.10 -- 0.20 SILICA, DIS- SOLVED (MG/L AS SIO2) 28 -- -- 30 — 31 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 296 -- -- 242 -- 279 SOLIDS, DIS- SOLVED (TONS PER DAY) 31.2 __ -- 18.2 -_ 46.7 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) <1 12 12 5 18 394 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.600 0.490 0.590 0.890 0.440 0.490 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.240 0.210 0.310 0.210 0.160 0.210 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 0.840 0.700 0.900 1.10 0.600 0.700 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 7.8 15 10 9.2 5.7 15 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 4.2 2.0 3.0 4.1 3.8 2.0 non-ideal count DATE OCT 1992 14... DEC 04... FEB 1993 10... APR 12.. . MAY 25... AUG 05... DATE OCT 1992 14.. . DEC 04... FEB 1993 10... APR 12.. . MAY 25... AUG 05... RIO GRANDE DE LOIZA BASIN 50055250 RIO CAGDITAS AT HIGHWAY 30 AT CAGUAS, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 249 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 12 17 13 11.3 9.5 17 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) 13 18 14 8.8 10 18 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N03) 57 78 29 33 46 82 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 2.60 1.80 2.60 2.30 1.70 3.80 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 -- -- 70 — -- ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) 5 — — <1 — -- CYANIDE TOTAL (MG/L AS CN) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) 4 -- -- 1 — -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) 30 — — 10 — -- METHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 1100 570 270 210 <0.10 <0.10 30 <0.010 20 <0.010 0.72 0.91 250 RIO GRANDB DE 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 AREA.--5.08 mi* (13.15 km'). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—November 1990 to current year. GAGE.—Water-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. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEE MAR HAY JUN JUL AUG SEP 1 3.4 8.1 2 3.4 3.7 3 3.4 4.7 4 3.3 27 5 7.2 8.0 6 73 5.9 7 7.9 5.7 8 5.4 e6.0 9 4.0 e!3 10 16 e30 11 5.1 e8.0 12 3.5 e6.4 13 3.4 e6.2 14 3.6 e6.4 15 3.4 e6.0 16 e3.5 e!5 17 e9.0 e29 18 e!9 e35 19 e9.0 ell 20 e6.0 e8.4 21 e4.5 e9.0 22 e6.4 ell 23 e4.0 elO 24 e6.8 e8.6 25 4.2 e7.2 26 3.5 e!5 27 3.5 e80 28 3.6 elSO 29 3.5 e20 30 3.2 el 13 31 3.7 TOTAL 239.4 667.3 MEAN 7.72 22.2 MAX 73 150 MIN 3.2 3.7 MED 4.0 8.8 AC-FT 475 1320 CFSM 1.52 4.38 IN. 1.75 4.89 e20 e9.0 e7.6 e7.3 e6.5 e6.3 e5.4 e4.9 e4.6 e4.5 e4.6 e4.5 e6.2 ell eS.O e5.4 e5.8 e5.2 e5.2 e4.4 e9.0 9.0 5.0 6.2 5.9 e337 e23 e!5 e31 e!9 el? 610.5 19.7 337 4.4 6.2 1210 3.88 4.47 STATISTICS OF MONTHLY MEAN DATA MEAN 12.5 13.0 MAX 25.3 22.2 (WY) 1991 1993 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 11.5 19.7 1993 4.63 1992 FOR 13 13 12 12 16 13 17 ell e7.2 e7.0 e7.2 e6.6 6.4 6.2 6.1 6.0 5.9 5.7 5.7 5.9 6.0 8.3 7.0 5.0 5.9 5.4 5.2 5.2 6.1 5.2 5.2 247.4 7.98 17 5.0 6.2 491 1.57 1.81 FOR WATER 9.84 13.6 1992 7.91 1991 5.0 5.0 5.7 4.7 4.7 .8 .6 .8 .7 .7 .5 .8 .8 .5 .6 7.8 4.3 3.8 3.7 4.1 4.6 3.6 3.5 3.7 3.6 4.5 3.6 3.2 __- ___ ___ 125.9 4.50 7.8 3.2 4.6 250 .89 .92 YEARS 1991 5.50 8.60 1991 3.47 1992 3.6 3.9 3.4 3.4 3.5 3.5 3.4 3.4 3.4 3.4 3.5 3.5 3.3 3.1 3.5 4.8 4.0 3.5 3.3 3.3 2.9 3.0 e4.0 e4.2 e3.7 e3.6 e3.3 e3.2 e3.2 e3.2 e3.2 108.2 3.49 4.8 2.9 3.4 215 .69 .79 - 1993 4.13 5.18 1991 3.49 1993 1992 CALENDAR YEAR 3238. 8. 337 2. 2. 6420 1. 23. 11 3. 2. 4 85 Dec 26 1 Apr 29 2 Apr 24 74 71 8 5 e3.1 e2.9 e2.7 e2.8 e2.8 e2.7 e3.0 e5.4 e7.4 e6.0 e6.2 eS.O e!3 e20 e!2 eS.O e6.8 e5.6 e6.7 e6.0 e6.5 eS.O e6.0 e4.9 e5.2 e6.8 e9.0 e8.4 elO e23 215.9 7.20 23 2.7 6.1 428 1.42 1.58 , BY WATER 4.52 7.20 1993 2.61 1992 e!2 e23 e26 e7.1 e6.8 e7.9 e!2 e7.8 e6.8 e!9 e9.0 e6.6 e6.2 e51 e!4 elO eS.O e6.0 5.7 5.7 5.5 5.4 18 7.4 7.9 36 18 ell elO e9.0 e9.7 388.5 , 12.5 51 5.4 9.0 771 2.47 2.84 YEAR (WY) 8.24 12.5 1993 5.96 1991 e8.9 e8.2 e7.5 e6.4 e5.9 e5.6 e5.4 e5.9 e7.0 8.7 7.0 6.9 6.8 10 11 8.1 7.0 7.1 27 20 9.4 9.3 7.8 7.1 6.9 7.0 6.7 10 7.3 7.4 259.3 8.64 27 5.4 7.2 514 1.70 1.90 5.94 8.64 1993 4.37 1991 FOR 1993 WATER YEAR 3774.5 10.3 337 2.7 2.9 1510 12.22 7490 2.04 27.64 17 6.2 3.5 Dec 26 Apr 3 Apr 1 Sep 18 Sep 18 5.8 7.2 8.1 6.2 5.7 5.4 14 6.1 4.8 5.0 80 17 11 9.6 14 10 8.3 7.9 7.7 7.2 7.2 14 23 24 11 9.4 8.4 7.8 7.5 7.1 7.1 367.5 11.9 80 4.8 7.9 729 2.33 2.69 10.9 16.5 1991 4.40 1992 WATER 8 10 6 337 2 2 1580 12 6100 1 22 13 4 3 7.0 6.8 6.8 6.6 6.6 6.5 6.4 6.4 6.1 6.0 6.1 6.3 6.2 6.6 6.9 24 7.4 6.3 6.1 5.7 5.3 22 8.8 6.2 5.7 5.6 5.3 5.2 4.9 4.9 4.7 225.4 7.27 24 4.7 6.3 447 1.43 1.65 6.33 7.64 1992 4.09 1991 YEARS 1991 - .42 .3 .22 Dec 26 .1 Apr 29 .2 Apr 24 Jan 5 .32 Jan 5 .66 .52 .7 .0 4.6 4.7 4.7 8.7 6.8 6.4 5.0 4.7 6.1 5.4 4.6 4.5 4.9 4.7 5.4 6.8 5.1 112 35 20 e6.8 e4.3 e6.2 e5.5 e5.7 eS.l e3.9 e7.2 eS.O e6.4 --- 319.2 10.6 112 3.9 5.4 633 2.09 2.34 8.32 10.6 1993 4.50 1991 1993 1993 1992 1992 1992 1992 1992 1992 e Estimated RIO GRANDE DE LOIZA BASIN 50055390 RIO BAIROA AT BAIROA, PR—Continued HATER-QUALITY RECORDS PERIOD OP RECORDS.-- Hater years 1991 to current year. PERIOD OP DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: November 1990 to September 1993. INSTRUMENTATION.-- DH-48 and automatic sediment sampler. EXTREMES POR PERIOD OP DAILY RECORD.— SEDIMENT CONCENTRATION: Maximum daily mean, 4,310 mg/L Dec. 26, 1992; Minimum daily mean, 2 m0/L Several days. SEDIMENT LOADS: Maximum daily mean, 3,910 tons (3,550 tonnes) Dec. 26, 1992; Minimum daily mean, 0.02 ton (0.02 tonne) Several days. 251 EXTREMES FOR HATER YEARS 1991-93.-- Water Year 1991 1992 1993 Suspended-sediment concentration (mg/L) maximum minimum Suspended-sediment discharge (tons per day) maximum minimum DAY 1,140 (Jul. 16) 890 (Jan. 05) 4,300 (Dec. 26) (Several days) (Several days) (Several days) 1,350 (Jul. 16) 433 (Jan. 05) 3,910 (Dec. 26) .06 (Several days) .02 (Several days) .02 (Apr, 03,1994) SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1990 TO SEPTsEMBER 1991 MEAN DISCHARGE (CPS) MEAN CONCEN- SEDIMENT TRATION DISCHARGE (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 e4, e4. e4. e5. e4.5 e4.5 e!4 e5.2 e4.4 e!4 e7.2 e5.4 e7.0 e8.4 e!20 e30 e!6 e94 e40 e45 e!30 e22 e!4 e23 e36 e54 e22 e!5 e!2 elO e9.4 785.5 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) NOVEMBER e9.0 e8.6 e8.2 e8.0 e7.6 e7.2 e7.2 e7.0 e6.8 e6.6 e6.4 e6.2 e6.2 e6.0 e6.0 e22 6.4 5.7 5.8 6.0 11 7.3 5.8 6.0 5.5 6.1 8.9 5.9 6.4 8.7 MEAN DISCHARGE (CPS) MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) 23 26 54 29 27 24 23 24 36 24 26 44 .36 .57 5.4 .57 .48 .37 .35 .40 .93 .41 .55 1.9 224.5 12 12 51 9.6 5.9 5.1 .9 .6 .5 .4 .6 .8 5.0 20 14 5.0 4.6 4.8 4.4 4.4 4.4 5.0 4.6 5.1 4.9 4.9 5.0 5.7 22 15 57 319.2 DECEMBER 75 82 263 31 8 7 7 7 8 10 12 14 15 169 172 15 8 10 13 15 16 18 20 21 22 22 22 24 132 72 298 6.4 9.7 72 1.0 .13 .10 .10 .10 .10 .12 .15 .18 .20 57 36 .20 .11 .13 .15 .17 .19 .24 .23 .28 .30 .30 .30 .58 31 5.4 83 305.86 e Estimated 252 RIO GRANDS OE LOIZA BASIN 50055390 RIO BAIROA AT BAIROA, 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 CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) JANUARY MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) 35 7.4 6.0 5.1 7.9 10 6.5 6.0 17 21 8.1 7.9 6.1 5.8 6.1 5.9 5.6 5.7 5.7 5.7 5.7 5.8 5.9 5.9 5.6 5.4 5.3 5.1 5.0 4.9 6.0 200 29 14 10 28 82 67 20 87 134 35 35 26 15 13 13 13 13 13 13 13 12 12 12 12 12 11 10 10 11 11 63 .66 .23 .15 1.1 3.7 1.2 .27 8.0 24 .81 .93 .44 .24 .21 .20 .19 .20 .20 .20 .19 .18 .19 .19 .18 .18 .16 .14 .14 .14 .18 5.6 5.7 5.2 5.0 94 11 6.2 5.2 4.8 4.7 6.6 6.2 5.5 4.7 4.8 5.5 4.5 6.8 6.7 5.0 5.2 .7 .8 .6 .8 .3 .4 .4 FEBRUARY 11 11 10 10 551 .18 .16 .14 .14 513 45 27 20 18 20 40 24 27 19 11 14 15 27 21 15 10 5 5 6 8 9 8 8 1.7 .50 .27 .24 .25 1.4 .51 .42 .24 .14 .56 .19 1.3 .43 .20 .15 .07 .07 .08 .10 .10 .10 .10 MEAN DISCHARGE (CFS) 4.4 4.2 4.4 4.7 5.2 5.8 4.6 5.0 4.6 4.8 4.4 4.2 4.1 4.3 4.2 4.2 4.1 4.4 4.1 3.8 3.8 25 4.8 4.2 4.1 9.2 4.8 4.0 3.9 3.7 3.5 MEAN CONCEN- TRATION (MG/L) MARCH 10 10 10 16 16 21 18 18 18 17 15 14 13 13 12 11 9 8 6 5 5 113 16 21 16 55 20 15 14 13 11 SEDIMENT DISCHARGE (TONS/DAY) .12 .12 .13 .23 .30 .35 .23 .24 .21 .21 .19 .16 .14 .14 .13 .11 .09 .09 .07 .06 .06 15 .21 .24 .17 4.1 .29 .15 .14 .13 .11 TOTAL 245.1 107.80 240.9 522.74 160.5 23.92 RIO GRANDB DE LOIZA BASIN 253 50055390 RIO BAIROA AT BAIROA, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MO/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 3.7 3.6 3.6 3.5 3.5 3.5 3.5 7.2 4.1 3.4 3.5 6.4 5.2 3.6 3.8 3.5 3.4 3.4 3.3 3.3 3.3 3.2 3.3 3.4 3.3 3.2 3.1 3.1 3.1 4.7 --_ APRIL 10 10 8 8 7 7 6 27 16 13 14 25 20 14 16 13 14 14 13 12 12 12 12 11 11 10 10 8 7 18 ___ .10 .09 .08 .08 .07 .06 .06 1.4 .19 .12 .13 1.0 .30 .13 .18 .12 .12 .12 .11 .10 .10 .10 .10 .10 .09 .08 .08 .07 .06 .89 ___ MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MAY MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) JUNE 3.6 3.4 3.4 3.5 3.7 3.7 6.2 11 5.2 4.9 4.6 4.0 3.4 3.3 3.2 3.2 3.1 9.4 55 7.3 3.8 4.0 3.0 3.0 7.6 3.3 3.1 3.0 3.0 3.0 3.0 17 16 17 18 22 15 60 48 21 19 20 31 27 23 21 19 15 42 307 144 66 40 31 27 35 14 14 13 11 10 10 .16 .15 .16 .16 .22 .14 1.4 4.2 .36 .38 .28 .36 .25 .20 .18 .16 .12 1.9 137 3.5 .70 .45 .25 .21 1.9 .13 .11 .11 .09 .08 .08 3.1 3.0 2.9 3.0 3.6 4.0 4.1 3.3 3.1 3.0 3.2 3.7 2.9 2.8 2.7 2.6 2.6 2.8 3.0 2.9 3.3 3.1 6.9 3.9 3.5 3.7 3.4 3.6 3.5 34 10 9 8 7 14 18 17 12 11 9 9 15 11 11 11 11 11 11 11 11 11 11 30 15 13 12 13 13 13 912 .08 .07 .06 .06 .17 .22 .39 .10 .09 .07 .08 .17 .08 .08 .08 .08 .08 .08 .08 .09 .10 .09 1.1 .17 .12 .12 .11 .12 .12 353 TOTAL 112.7 6.23 184.9 155.39 131.2 357.26 254 RIO GRANDE DE LOIZA BASIN 50055390 RIO BAIROA AT BAIROA, 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 TOTAL e MEAN DISCHARGE (CFS) 40 6.9 5.6 5.0 4.5 4.3 28 8.0 4.8 4.0 4.0 3.9 4.0 3.6 17 191 9.8 79 14 7.2 5.9 20 e5.6 e5.2 e4.8 e4.5 e4.3 e7.0 e3.7 e3.5 e3.8 512.9 Estimated MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) JULY 185 27 21 20 18 16 235 176 162 144 117 88 58 28 106 1140 51 513 60 31 25 85 32 31 28 24 21 67 81 28 29 ... MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AUGUST 36 .54 .35 .26 .22 .18 87 3.9 2.1 1.6 1.2 .93 .61 .27 22 1350 1.5 443 2.8 .61 .40 13 e.56 e.42 e.35 e.28 e.24 e3.2 el.O e.26 e.30 1975.08 e4.2 e3.5 e3.2 e3.3 e3.5 e3.3 e3.3 e3.1 e3.3 e3.1 e3.0 e2.9 e2.8 e2.9 e2.8 e3.1 e3.2 e3.3 e3.2 e3.1 e3.1 e7.4 e5.2 e4.3 e4.0 e3.8 el6 e6.4 e4.5 e4.1 e3.9 126.8 28 16 15 15 14 14 14 13 13 12 11 11 10 8 8 10 10 10 10 10 10 69 21 15 11 8 145 36 38 38 15 —— e.32 e.15 e.12 e.13 e.14 e.12 e.12 e.10 e.ll e.10 e.08 e.08 e.07 e.07 e.06 e.08 e.08 e.08 e.08 e.08 e.08 e20 e.32 e.17 e.ll e.09 e34 el. 2 e.48 e.41 e.14 59.17 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) SEPTEMBER e3.7 e3.8 e3.8 e3.7 e3.6 e3.4 e3.5 e3.7 e3.9 e3.8 e3.8 e3.7 e3.7 e3.7 e3.6 e3.5 elS e4.8 eS.O e4.0 e3.9 e6.0 e4.6 e4.2 e3.8 e3.7 e4.6 e4.4 e6.4 e5.8 --- 135.1 15 15 14 13 13 12 12 12 12 11 10 10 8 7 6 5 565 232 97 9 13 78 57 47 43 37 27 20 31 19 --- ... e.13 e.14 e.14 e.13 e.12 e.12 e.12 e.12 e.12 e.ll e.10 e.09 e.08 e.07 e.06 e.05 e80 e3.0 elO e.10 e.20 e21 e4.5 e.54 e.47 e.38 e.29 e.24 el. 4 e.27 --- 124.09 RIO GRANDE DE LOIZA BASIN 50055390 RIO BAIROA AT BAIROA, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 255 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 e4.0 e7.0 3.9 3.2 4.0 3.2 3.2 3.2 3.3 3.2 3.1 3.1 3.0 3.3 3.8 3.4 3.3 3.0 3.0 2.9 3.7 5.0 4.6 3.3 3.0 3.0 2.9 2.7 5.1 24 5.9 13 24 23 103 18 16 14 12 12 12 11 10 10 9 8 8 9 10 10 10 14 17 16 10 9 9 9 8 19 106 22 e.14 e.46 .24 .91 .20 .14 .11 .10 .10 .10 .09 .08 .08 .09 .09 .08 .08 .09 .09 .08 .18 .46 .22 .09 .08 .08 .07 .06 1.4 27 .42 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) NOVEMBER 17 11 4.7 4.8 8.9 5.8 18 57 21 6.7 e5.3 e4.8 e4.6 e4.4 e4.2 e4.0 3.8 3.8 3.8 3.9 9.2 16 12 8.8 6.3 6.1 10 4.3 4.1 4.0 72 64 30 25 36 21 78 268 89 29 18 15 15 15 15 15 15 15 15 14 37 57 45 64 25 20 42 20 14 7 18 4.0 .39 .30 1.3 .33 7.7 67 8.4 .57 e.25 e.20 e.18 e.18 e.18 e.16 .16 .16 .16 .14 3.3 2.9 3.0 1.9 .43 .33 4.0 .24 .15 .09 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) DECEMBER TOTAL 133.3 33.41 278.3 126.10 3.9 3.9 e5.6 e6.4 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 5 5 5 6 8 13 14 13 11 10 8 7 12 15 10 10 10 10 8 60 33 12 13 14 15 15 15 15 15 15 16 .06 .06 e.08 e.10 .11 .15 .16 .13 .11 .10 .09 .08 e.40 e.21 .10 .10 .10 .09 .08 e8.6 el. 5 .14 .13 .14 .15 .15 .15 .16 .16 .16 .16 13.91 e Estimated 256 RIO GRANDS DB LOIZA BASIN 50055390 RIO BAIROA AT BAIROA, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAY MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (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 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 16 16 16 16 890 458 49 48 49 49 50 53 55 51 45 122 39 24 26 25 22 18 16 17 19 20 20 19 20 22 24 e.16 e.16 e.16 e.16 e433 e!24 el. 3 e.77 e.75 .77 .55 .54 .60 .49 .37 32 2.3 e.25 e.27 e.25 e.22 e.18 e.15 e.16 e.19 e.17 e.19 e.18 e.19 e.21 e.22 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) FEBRUARY MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MARCH 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 24 23 22 18 14 12 15 21 27 27 22 24 29 31 25 16 12 16 24 31 36 39 43 32 14 6 4 4 4 e.21 e.22 e.20 e.16 e.13 e.12 e.14 e.20 e.27 e.30 e.21 e.22 e.27 e.29 e.22 e.15 e.12 e.15 e.22 e.27 e.31 e.34 .42 .34 .12 .06 .04 .04 .04 3.0 2.8 2.8 2.8 2.8 2.8 2.8 e2.6 e2.6 e2.7 e2.6 e2.5 e2.5 e2.4 e2.7 e2.6 e5.2 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 5 4 7 7 7 7 8 8 8 7 5 12 14 19 23 17 6 3 3 171 26 21 14 .04 .04 .06 .06 .06 .06 .06 e.06 e.06 e.06 e.04 e.03 e.02 e.02 e.03 e.02 e.06 e.04 e.02 e.08 e.10 e.13 e.14 e.10 e.04 e.02 e.02 e!4 e.32 e.16 e.09 TOTAL 423.0 600.91 100.7 5.78 115.0 142.03 e Estimated RIO GRANDE DE LOIZA BASIN 50055390 RIO BAIRQA AT BAIROA, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 257 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 MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) e2.3 e2.4 e2.4 e2.4 e2.3 e2.4 e2.7 e2.6 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 APRIL 11 7 8 15 25 34 34 26 15 7 6 8 11 11 8 7 10 12 26 26 23 21 19 17 15 14 12 10 8 7 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MAY e.06 e.05 e.05 e.09 e.15 e.21 e.24 e.18 e.09 e.05 e.04 e.06 e.07 e.06 e.05 e.05 e.07 e.ll el. 3 e.24 e.18 e.14 e.12 e.ll e.09 e.08 e.60 e.06 e.05 e.04 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 e4.7 e6.4 e4.6 e32 e30 el4 e!2 elO 7.9 6.7 5.9 5.3 10 15 21 27 29 23 15 8 6 5 5 4 3 3 5 12 20 26 28 28 27 23 18 14 12 11 9 8 7 7 7 e.06 e.13 e.16 e.16 e.17 e.16 e.09 e.05 e.04 e.03 e.02 e.04 e.02 e.02 e.03 - e.ll e.25 e.23 e.32 e.36 e.46 e.28 el. 5 el.l e.44 e.34 e.24 .17 .14 .11 .10 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) JUNE 5.1 5.0 4.0 9.4 3.8 4.8 5.1 5.6 5.9 5.5 e4.5 e8.6 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 7 6 5 37 13 15 15 18 20 18 20 14 21 17 5 6 8 10 10 10 16 13 5 6 7 6 5 4 5 7 ___ .10 .09 .06 10 .13 .26 .24 .59 .60 .31 e.24 e.32 e.46 e.20 e.06 e.12 e.10 e.10 e.10 e.10 e.27 e.15 e.07 e.07 e.06 e.06 e.04 e.04 e.04 e.06 78.4 4.69 192.8 7.33 143.9 15.04 e Estimated 258 RIO GRANDS DE LOIZA BASIN 50055390 RIO BAIROA AT BAIROA, 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 MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) 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 6.1 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 JULY 10 10 8 7 5 3 2 2 2 2 4 2 2 7 16 16 18 12 6 3 2 3 11 14 11 6 4 4 4 4 5 TOTAL 136.4 —— YEAR e 2276.2 Estimated MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AUGUST .07 .07 .06 .06 .07 .03 .02 .02 .02 .02 .12 .04 .04 .19 .38 .67 .30 .15 .07 .03 .03 .04 .30 .18 .11 .06 .04 .04 .04 .04 .04 3.35 1815.80 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 5 10 18 64 405 171 84 21 15 8 12 8 7 6 5 4 3 3 4 8 8 4 3 6 3 4 5 5 5 10 12 —— .04 .12 .35 5.6 262 18 4.1 .33 .19 .10 .30 .12 .08 .07 .07 .05 .04 .04 .05 .08 .07 .04 .03 .08 .02 .03 e.04 e.04 e.08 e.16 .25 292.57 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) SEPTEMBER 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 19 14 5 30 15 41 248 13 28 10 13 8 13 6 5 6 6 4 402 148 35 12 10 10 9 8 8 8 14 19 —— 1.6 .14 .06 3.8 .24 4.5 249 .17 .91 .09 .40 .07 .51 .06 .04 .05 .05 .03 e293 e!4 e.94 .14 .09 .09 .09 .08 .08 .08 .16 .21 570.68 RIO GRANDE DE LOIZA BASIN 50055390 RIO BAIROA AT BAIROA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 259 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 3.4 3.4 3.4 3.3 7.2 73 7.9 5.4 4.0 16 5.1 3.5 3.4 3.6 3.4 e3.5 e9.0 e!9 e9.0 e6.0 e4.5 e6.4 e4.0 e6.8 4.2 3.5 3.5 3.6 3.5 3.2 3.7 8 8 8 8 31 791 27 17 11 95 16 7 8 10 12 e!9 e38 e50 50 47 45 40 33 26 20 17 13 10 10 11 11 .08 .08 .08 .08 3.0 791 1.3 .45 .12 19 .27 .07 .07 .10 .12 e.18 e.91 e2.6 el. 2 e.75 e.54 e.68 e.35 e.47 .24 .16 .12 .10 .11 .10 .10 MEAN DISCHARGE (CPS) 8.1 3.7 4.7 27 8.0 5.9 5.7 e6.0 e!3 e30 e8.0 e6.4 e6.2 e6.4 e6.0 e!5 e29 e35 ell e8.4 e9.0 ell elO e8.6 e7.2 e!5 e80 e!50 e20 el 13 MEAN CONCEN- TRATION (MG/L) NOVEMBER 29 20 23 308 119 32 21 21 17 12 9 8 10 15 21 28 36 78 113 110 110 110 110 110 110 110 577 1480 84 964 SEDIMENT DISCHARGE (TONS /DAY) 1.5 .21 .44 41 2.9 .54 .33 .33 .58 .94 .20 .14 e.16 e.26 e.34 el.l e2.8 e7.3 e3.3 e2.5 e2.7 e3.3 e3.0 e2.6 e2.1 e4.5 el25 e599 e4.5 e294 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) DECEMBER TOTAL 239.4 824.43 667.3 1107.57 e20 e9.0 e7.6 e7.3 e6.5 e6.3 e5.4 e4.9 e4.6 e4.5 e4.6 e4.5 e6.2 ell eS.O e5.4 e5.8 e5.2 e5.2 e4.4 e9.0 e9.0 eS.O e6.2 e5.9 e337 e23 e!5 e31 e!9 el7 610.5 83 18 19 20 20 20 19 17 17 20 25 29 28 24 22 22 20 16 12 10 28 28 13 17 16 4300 102 56 152 112 169 e4.5 e.44 e.39 e.40 e.36 e.34 e.28 e.23 e.21 e.24 e.31 e.35 e.46 e.70 e.30 e.32 e.31 e.23 e.17 e.12 e.68 e.68 e.18 e.28 e.26 e3910 e6.3 e2.3 e!3 e5.7 e7.4 3957.44 e Estimated 260 RIO GRANDS DE LOIZA BASIN 50055390 RIO BAIROA AT BAIROA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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 13 13 12 12 16 13 17 ell e7.2 e7.0 e7.2 e6.6 6.4 6.2 6.1 6.0 5.9 5.7 5.7 5.9 6.0 8.3 7.0 5.0 5.9 5.4 5.2 5.2 6.1 5.2 5.2 134 117 106 98 102 47 71 28 20 20 20 15 10 10 10 10 10 10 10 10 10 26 20 7 12 7 7 7 17 7 7 FEBRUARY 4.9 5.0 4.1 5.0 3.6 5.7 3.0 5.5 1.9 4.0 .83 .38 .38 .38 .27 .17 .17 .17 .7 .7 .8 .6 .8 .7 .7 .5 .8 .8 .5 .6 .17 7.8 .16 4.3 .16 3.8 .16 3.7 .16 4.1 .16 4.6 .94 3.6 .62 3.5 .10 3.7 .21 3.6 .10 4.5 .10 3.6 .10 3.2 .39 .10 .10 6 5 13 6 9 11 12 12 11 11 8 5 4 6 8 27 10 5 3 4 6 8 8 8 8 13 8 10 ___ .08 .06 .23 .08 .11 .13 .14 .14 .13 .13 .10 .07 .06 .07 .10 1.3 .12 .05 .03 .05 .08 .09 .08 .08 .08 .24 .08 .09 ___ ___ ___ MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MARCH 3.6 3.9 3.4 3.4 3.5 3.5 3.4 3.4 3.4 3.4 3.5 3.5 3.3 3.1 3.5 4.8 4.0 3.5 3.3 3.3 2.9 3.0 e4.0 e4.2 e3.7 e3.6 e3.3 e3.2 e3.2 e3.2 e3.2 5 5 4 4 5 5 5 5 4 5 10 12 8 6 5 15 8 7 7 8 11 13 14 12 7 4 4 5 5 5 S .06 .05 .03 .03 .05 .05 .04 .04 .04 .05 .09 .11 .08 .05 .04 .33 .10 .07 .06 .07 .09 .11 .16 .13 .06 .04 .04 .04 .05 .05 .04 TOTAL 247.4 33.48 125.9 4.00 108.2 2.25 e Estimated RIO GRANDS DE LOIZA BASIN 261 50055390 RIO BAIROA AT BAIROA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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 e3.1 e2.9 e2.7 e2.8 e2.8 e2.7 e3.0 eS.4 e7.4 e6.0 e6.2 e8.0 e!3 e20 e!2 eS.O e6.8 e5.6 e6.7 e6.0 e6.5 eS.O e6.0 e4.9 e5.2 e6.8 e9.0 e8.4 elO e23 APRIL 4 3 3 5 6 7 10 12 14 15 15 18 22 24 22 17 13 10 9 14 19 19 16 14 14 15 15 15 15 15 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MAY e.04 e.03 e.02 e.04 e.04 e.05 e.08 e.17 e.27 e.23 e.26 e.38 e.77 el. 3 e.70 e.37 e.24 e.14 e.16 e.22 e.33 e.24 e.25 e.18 e.19 e.27 e.36 e.34 e.40 e.94 ___ e!2 e23 e26 e7.1 e6.8 e7.9 e!2 e7.8 e6.8 e!9 e9.0 e6.6 e6.2 e51 e!4 elO eS.O e6.0 5.7 5.7 5.5 5.4 18 7.4 7.9 36 18 ell elO e9.0 e9.7 15 15 15 15 14 13 12 13 19 28 36 43 43 38 33 26 19 14 11 8 6 5 103 22 17 384 79 27 8 7 5 e.48 e.94 el.l e.27 e.25 e.28 e.39 e.27 e.34 el. 4 e.88 e.76 e.71 e5.2 el. 3 e.71 e.40 e.22 .16 .12 .09 .08 17 .47 .38 143 5.1 el.O e.24 e.17 e.15 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) JUNE e8.9 e8.2 e7.5 e6.4 e5.9 eS.6 e5.4 eS.9 e7.0 8.7 7.0 6.9 6.8 10 11 8.1 7.0 7.1 27 20 9.4 9.3 7.8 7.1 6.9 7.0 6.7 10 7.3 7.4 7 13 17 19 20 22 27 33 25 12 8 7 9 37 43 49 28 23 155 115 51 31 23 20 15 12 11 50 33 49 ___ .18 .28 .33 .32 .31 .32 .39 .52 .47 .29 .16 .14 .16 2.5 1.6 1.2 .56 .56 15 9.1 1.4 .71 .50 .39 .28 .21 .21 3.4 .72 .93 TOTAL 215.9 9.01 388.5 183.86 259.3 43.14 e Estimated 262 RIO GRANDE OB LOIZA BASIN 50055390 RIO BAIROA AT BAIROA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 MEAN MEAN CONCBN- SEDIMENT DISCHARGE THAT ION 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 5.8 7.2 8.1 6.2 5.7 5.4 14 6.1 4.8 5.0 80 17 11 9.6 14 10 8.3 7.9 7.7 7.2 7.2 14 23 24 11 9.4 8.4 7.8 7.5 7.1 7.1 367.5 3774.5 JULY 44 40 30 19 16 16 83 18 13 16 785 76 28 17 57 27 15 11 12 12 12 56 115 130 38 31 19 10 9 8 8 ... MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AUGUST .70 .82 .81 .35 .26 .24 14 .33 .17 .29 401 4.4 .91 .46 5.8 .85 .33 .24 .24 .24 .24 4.2 10 14 1.2 .93 .47 .20 .18 .17 .16 464.19 9195.49 7.0 6.8 6.8 6.6 6.6 6.5 6.4 6.4 6.1 6.0 6.1 6.3 6.2 6.6 6.9 24 7.4 6.3 6.1 5.7 5.3 22 8.8 6.2 5.7 5.6 5.3 5.2 4.9 4.9 4.7 225.4 8 7 5 5 6 9 10 10 14 21 25 22 14 10 13 118 20 11 10 10 10 136 26 10 6 6 6 6 6 8 10 ... .15 .13 .10 .08 .11 .16 .18 .18 .24 .33 .41 .38 .23 .17 .35 11 .47 .19 .16 .15 .14 27 .72 .17 .10 .09 .08 .08 .08 .10 .12 43.85 MEAN DISCHARGE (CFS) MEAN CONCBN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/ DAY) SEPTEMBER 4.6 4.7 4.7 8.7 6.8 6.4 5.0 4.7 6.1 5.4 4.6 4.5 4.9 4.7 5.4 6.8 5.1 112 35 20 e6.8 e4.3 e6.2 e5.5 e5.7 e5,l e3.9 e7.2 eS.O e6.4 --- 319.2 10 9 7 29 23 21 14 10 16 16 7 5 11 14 18 22 14 1500 194 93 31 28 33 18 43 18 9 30 26 24 ... .12 .11 .09 1.9 .60 .54 .21 .12 .41 .26 .10 .06 .21 .18 .43 .79 .20 2480 22 7.0 e.59 e.31 e.85 e.33 el. 9 e.32 e.10 el. 3 e.68 e.56 2522.27 e Estimated DATE DEC 1992 26... MAY 1993 26... SEP 18... 18... RIO GRANDB DB LOIZA BASIN 50055390 RXO BAIROA AT BAIROA, PR—Continued HATER QUALITY DATA, HATER YEAR JULY 1992 TO SEPTEMBER 1993 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT 263 TIME 1540 1631 1545 1704 DIS- CHARGE, INST. CUBIC FEET PER SECOND 330 243 550 634 SEDI- MENT, SUS- PENDED (MG/L) 3220 3860 14600 7700 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 2870 2530 21700 13200 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM 54 27 26 39 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM 62 41 31 55 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 72 48 43 65 DATE DEC 1992 26... MAY 1993 26... SEP 18.. . 18... SBD. SUSP. FALL DIAM. PERCENT FINER THAN .016 MM 75 57 53 74 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM 84 68 62 78 SBD. SUSP. SIEVE DXAM. PERCENT FINER THAN .062 MM 94 73 72 89 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 97 81 79 92 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 99 90 88 95 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 99.5 98 96 99 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 99.6 100 99 100 264 RIO GRANDE DE LOIZA BASIN 50055390 RIO BAIROA AT BAIROA, PR—Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT DATE OCT 1992 07... NOV 28... HAY 1993 26... JUL 24... SEP 18. . . TIME 1714 1621 1359 0830 1720 STREAM- FLOW, INSTAN- TANEOUS (CFS) 6.7 ISO 88 54 614 SEDI- MENT, SUS- PENDED (MG/L) 123 777 565 750 10600 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 2.2 315 134 109 17500 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 100 99 76 97 78 RIO GRANDB DB LOIZA BASIN 265 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 Grande de Loiza, and 1.4 mi (2.3 km) north of Caguas plaza. DRAINAGE AREA.--5.4 mi 1 (14.0 km'). PERIOD OF RECORD.—Water years 1958, 1962-66, 1973-74, 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 07. .. DEC 07... FBB 1993 11. .. APR 12... JUN 09. .. AUG 05... TIME 1240 0915 0745 1445 1330 1125 DIS- CHARGE, INST. CUBIC FEET PER SECOND 2.7 6.6 7.9 9.0 5.8 4.5 SPE- CIFIC CON- DUCT- ANCE (US/CM) 300 430 498 420 400 398 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.4 7.7 7.8 7.1 7.8 7.0 TEMPER- ATURE WATER (DBG C) 26.1 22.7 22.3 26.5 27.6 26.4 TUR- BID- ITY (NTU) 53 29 2.7 28 53 0.40 OXYGEN, DIS- SOLVED (MG/L) 6.5 6.6 6.5 4.7 7.7 6.6 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 82 79 77 58 97 80 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 19 <10 <10 18 45 <10 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 35000 15000 210000 K23000 K44000 K10000 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 20000 K2700 6400 24000 K160000 K2600 DATE OCT 1992 07. .. DEC 07. .. FBB 1993 11. .. APR 12... JUN 09... AUG 05... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MG/L TOT FLD SOLVED AS CACO3) CACO3 MG/L AS (MG/L MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS NA) 130 6 22 13 21 110 1 29 10 19 150 5 37 15 24 SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY SIUM, WAT WH DIS- TOT FET SULFIDB SOLVED FIELD TOTAL (MG/L MG/L AS (MG/L AS K) 0.6 2.9 0.8 4.4 0.8 3.7 CACO3 110 130 160 100 160 120 CHLO- SULFATB RIDE, DIS- DIS- SOLVED SOLVED (MG/L 1.4 12 <0.5 19 18 (MG/L AS S) AS S04) AS CL) 27 25 28 SOLIDS, RESIDUE DATE OCT 1992 07... DEC 07... FBB 1993 11.. . APR 12... JUN 09.. . AUG 05... FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.10 -- -- 0.10 -- 0.20 SILICA, DIS- SOLVED (MG/L AS SI 02) 30 -- -- 23 -- 31 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 172 -- -- 189 -- 239 SOLIDS, DIS- SOLVED (TONS PER DAY) 1.25 -- -- 4.58 — 2.90 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 29 16 2 40 515 1 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 1.55 0.230 0.120 0.100 0.510 0.130 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.050 0.130 0.060 0.080 0.100 0.080 NITRO- GEN, N02+N03 TOTAL (MG/L AS N) 1.60 0.360 0.180 0.180 0.610 0.210 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.130 8.70 11.0 13.0 6.80 0.610 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.47 2.3 5.0 5.0 2.5 13 non-ideal count 266 RIO GRANDB DB LOIZA BASIN 50055400 RIO BAIROA NEAR CAGUAS, PR--Continued WATER-QUALITY DATA, WATBR YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 07... DEC 07... FBB 1993 11.. . APR 12... JUN 09... AUG 05... DATE OCT 1992 07.. . DEC 07... FBB 1993 11.. . APR 12.. . JUN 09... AUG 05.. . NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.60 11 16 18 9.3 14 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) 2.2 19 13 12 9.9 10 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS NO3) 9.7 50 72 80 44 63 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.350 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) 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 -- -- 120 -- -- 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 -- -- 5 -- -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CD) <10 -- — 20 — -- METHY- LBNB BLUB ACTIVE SUB- STANCE (MG/L) 1300 1100 330 110 <0.10 <0.10 20 •cO.010 <0.010 0.06 0.13 RIO GRANDB DB LOIZA BASIN 50055750 RIO GURABO BELOW BL MANGO, PR 267 LOCATION.--Lat 18°14'02", long 65°53'07", Hydrologic Unit 21010005, on left bank, 2.43 mi (3.91 km) northeast of Plaza de Juncos, 1.3 mi (2.1 km) southeast of Bscuela La Placita and 0.35 mi (0.56 km ) southwest of Bl Mango. DRAINAGE AREA.--22.3 mi 1 (57.8 km'). HATER-DISCHARGE RECORDS PERIOD OF RECORD.--Harch 1990 to current year. GAGE.—Hater-stage recorder. Elevation of gage is 230 ft (70 m), from topographic map. REMARKS.--Records fair except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. Low-flow is affected by sewage discharges from a water treatment plant, 0.60 mi (0.96m) upstream from gaging station since 1990. DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 21 4.1 2 12 2.5 3 5.1 24 4 3.6 122 5 3.5 18 6 16 47 7 8.3 44 8 3.7 6.6 9 3.3 8.6 10 3.0 59 11 2.3 7.5 12 2.0 3.7 13 1.8 8.9 14 1.6 4.4 15 1.4 96 16 2.0 100 17 3.1 34 18 1.6 301 19 1.5 72 20 1.8 16 21 2.5 15 22 1.6 134 23 1.5 34 24 1.4 10 25 1.7 9.3 26 1.5 7.3 27 1.1 282 28 1.2 666 29 2.2 51 30 1.4 872 31 9.7 TOTAL 124.4 3059.9 MEAN 4.01 102 MAX 21 872 MIN 1.1 2.5 AC-FT 247 6070 CFSM .18 4.57 IN. .21 5.10 32 17 11 17 10 71 11 6.0 4.5 4.0 3.4 3.0 2.8 2.8 3.2 2.8 2.6 2.6 2.7 2.5 2.2 3.3 3.6 5.9 13 302 27 12 274 515 42 1411.9 45.5 515 2.2 2800 2.04 2.36 STATISTICS OF MONTHLY MEAN DATA MEAN 64.6 82.1 MAX 161 109 (WY) 1991 1992 MIN 4.01 35.5 (WY) 1993 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 42.9 59.0 1991 24.1 1992 FOR 27 18 20 21 21 33 84 48 31 28 21 18 17 16 16 15 15 13 13 12 11 14 033 13 023 17 19 e60 269 28 22 996 32.1 269 11 1980 1.44 1.66 14 31 28 15 11 10 9.8 9.1 8.5 8.2 7.6 10 13 8.5 8.0 7.6 7.3 8.7 7.1 6.9 14 9.8 7.3 7.0 6.3 6.2 6.2 6.1 ___ --- 292.2 10.4 31 6.1 580 .47 .49 FOR WATER YEARS 1990 44.7 65.8 1992 32.1 1993 22.4 44.0 1991 10.4 1993 5.5 5.4 5.2 5.1 5.1 .9 .8 .8 .8 .8 .6 .9 .6 .6 .6 4.9 9.0 9.9 6.7 6.2 6.5 4.9 4.6 9.1 9.0 6.1 5.5 5.1 4.7 4.3 4.3 174.5 5.63 9.9 4.3 346 .25 .29 - 1993 11.1 18.1 1991 5.63 1993 1992 CALENDAR YEAR 18842. 51. 945 1. 1. 37370 2. 31. 122 8. 2. 0 5 Sep 20 1 Oct 27 4 Oct 22 31 43 9 6 4.3 4.1 3.9 4.2 4.2 7.2 5.3 5.3 6.5 5.1 4.2 4.4 23 12 9.3 8.1 8.8 5.0 17 9.1 16 7.5 15 67 13 7.7 6.3 8.9 8.3 30--- 330.7 11.0 67 3.9 656 .49 .55 134 111 21 12 8.6 8.3 7.5 6.9 140 36 12 7.0 4.5 5.0 6.7 3.1 2.3 3.8 2.3 1.4 1.8 1.3 2.8 2.6 5.3 4.7 40 35 14 11 8.8 660.7 21.3 140 1.3 1310 .96 1.10 8.1 7.5 7.4 6.8 6.2 5.6 5.0 14 35 35 16 9.8 82 145 29 13 9.7 8.6 1290 417 55 33 24 19 16 13 12 11 10 18 2361.7 78.7 1290 5.0 4680 3.53 3.94 13 21 94 31 15 11 40 93 20 12 1710 184 74 51 208 234 46 28 22 19 16 328 831 154 55 107 62 30 21 17 15 4562 147 1710 11 9050 6.60 7.61 14 12 11 11 10 9.8 9.1 8.6 8.0 7.8 7.8 7.8 7.4 6.9 7.0 11 11 7.6 6.4 6.3 6.0 5.5 25 28 23 10 7.6 7.6 6.7 6.5 9.1 315.5 10.2 28 5.5 626 .46 .53 12 9.3 7.7 7.7 69 29 11 150 56 81 28 13 10 9.2 8.3 42 115 84 40 18 12 11 10 9.4 11 9.9 9.8 47 24 225--- 1169.3 39.0 225 7.7 2320 1.75 1.95 , BY WATER YEAR (WY) 9.30 11.0 1993 7.52 1990 FOR 1993 15458. 42. 1710 1. 1. 5030 16. 30660 1. 25. 73 9. 3. 41.3 123 1992 4.83 1990 WATER YEAR 8 4 Jul 11 1 Oct 27 4 Oct 22 Jun 19 82 Jun 19 90 79 8 0 58.9 117 1992 14.7 1991 54.7 147 1993 12.8 1992 WATER 45. 52. 41. 1710 1. 1. 5870 17. 32920 2. 27. 88 11 3. 28.1 35.2 1990 10.2 1993 YEARS 1990 4 3 6 Jul 1 Oct 4 Oct Nov 38 Nov 04 69 7 50.1 81.9 1992 34.9 1990 - 1993 1992 1991 11 1993 27 1992 22 1992 8 1991 8 1991 e Estimated 268 RIO GRANDB DB LOIZA BASIN SOOSS7SO RIO QDRABO BELOW EL MANGO, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORDS.-- Water years 198S to 1986 and water year 1989 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE! March 1990 to September 1993. INSTRUMENTATION.-- DH-48 and automatic sediment sampler. i, 1,000 mg/L Oct. 21, 1990; Minimum daily mean. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATION: Maximum daily 4 mg/L April 7,1991. SEDIMENT LOADS: Maximum daily mean, 7,110 tons (6,450 tonnes) Nov. 08, 1991; Minimum daily mean, 0.03 ton (0.02 tonne) May 22, 1993. EXTREMES FOR WATER YEAR 1993.-- SEDIMENT CONCENTRATIONi Maximum daily mean, 657 mg/L June 19, 1993; Minimum daily mean, 7 mg/L several days. SEDIMENT LOADS: Maximum daily mean, 4,800 tons (4,350 tonnes) July 11, 1993; Minimum daily mean, 0.03 ton (0.02 tonne) May 22, 1993. SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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 21 12 S.I 3.6 3.S 16 8.3 3.7 3.3 3.0 2.3 2.0 1.8 1.6 1.4 2.0 3.1 1.6 1.5 1.8 2.S 1.6 l.S 1.4 1.7 l.S 1.1 1.2 2.2 1.4 9.7 124.4 56 33 22 19 14 41 32 22 22 21 20 18 15 15 9 15 27 23 19 IS 12 11 10 10 11 11 11 13 16 13 33 __- 4.4 l.S .30 .19 .12 S.2 .84 .23 .20 .17 .13 .10 .07 .06 .04 .10 .25 .10 .08 .08 .08 .OS .04 .04 .OS .05 .04 .OS .10 .05 2.1 16.81 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) NOVEMBER 4.1 2.5 24 122 18 47 44 6.6 8.6 59 7.S 3.7 8.9 4.4 96 100 34 301 72 16 IS 134 34 10 9.3 7.3 282 666 51 872 --- 3059.9 21 18 57 180 52 92 113 28 31 85 35 21 33 23 158 232 79 282 129 SO 48 195 83 S3 34 32 208 469 105 484 --- .25 .14 7.3 75 3.4 35 24 .55 .82 25 .86 .20 .96 .27 105 112 11 434 32 2.5 2.3 84 11 1.4 .87 .65 486 12 SO 19 2270 4995.47 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) DECEMBER 32 17 11 17 10 71 11 6.0 4.5 4.0 3.4 3.0 2.8 2.8 3.2 2.8 2.6 2.6 2.7 2.5 2.2 3.3 3.6 5.9 13 302 27 12 274 SIS 42 1411.9 100 SS 39 52 37 107 39 30 27 24 21 20 19 18 18 18 18 18 17 IS 14 17 20 25 43 271 67 40 245 395 96 9.2 2.6 1.2 3.4 1.1 54 1.3 .48 .34 .25 .20 .16 .14 .14 .15 .14 .13 .14 .13 .11 .09 .19 .23 .50 2.1 489 6.9 1.3 450 900 12 1937.62 RIO GRANDB DB LOIZA BASIN SOOSS7SO RIO GORABO BELOW EL MANGO, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 269 MEAN MEAN CONCEN- 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 27 18 20 21 21 33 84 48 31 28 21 18 17 16 16 15 15 13 13 12 11 14 e33 13 e23 17 19 e60 269 28 22 68 47 56 59 56 77 137 100 60 53 47 41 36 31 25 21 20 21 22 23 24 39 61 21 57 50 51 145 268 71 35 5.2 2.5 3.1 3.6 3.3 7.0 41 15 5.1 4.2 2.7 2.0 1.6 1.3 1.1 .83 .82 .75 .74 .74 .73 2.1 e7.4 .77 e4.8 2.4 2.8 e51 318 6.2 2.5 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) PBBRUARY TOTAL 996 501.28 14 31 28 15 11 10 9.8 9.1 8.5 8.2 7.6 10 13 8.5 8.0 7.6 7.3 8.7 7.1 6.9 14 9.8 7.3 7.0 6.3 6.2 6.2 6.1 292.2 12 48 96 47 26 21 20 20 20 20 19 34 36 23 20 18 15 13 12 11 42 27 20 19 18 17 16 14 .44 9.5 8.0 2.0 .82 .59 .51 .48 .46 .45 .40 1.1 1.4 .52 .44 .37 .30 .30 .23 .20 1.8 .77 .39 .34 .30 .27 .26 .22 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) MARCH 32.86 S.S 5.4 5.2 5.1 5.1 .9 .8 .8 .8 .8 .6 .9 .6 .6 .6 4.9 9.0 9.9 6.7 6.2 6.5 4.9 4.6 9.1 9.0 6.1 5.5 5.1 4.7 4.3 4.3 174.5 11 10 11 15 20 21 19 16 12 10 9 7 7 12 27 44 45 31 19 14 12 15 22 33 33 27 18 9 9 9 9 .16 .14 .15 .20 .26 .27 .25 .20 .15 .13 .11 .09 .10 .15 .34 .57 1.1 .78 .36 .24 .20 .19 .29 .87 .82 .47 .28 .13 .12 .11 .10 9.33 e Estimated 270 RIO GRANDE DE LOIZA BASIN 50055750 RIO QURABO BELOW EL MANGO, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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 4.3 4.1 3.9 4.2 4.2 7.2 5.3 5.3 6.5 5.1 4.2 4.4 23 12 9.3 8.1 8.8 5.0 17 9.1 16 7.5 15 67 13 7.7 6.3 8.9 8.3 30 ___ APRIL 8 8 8 10 10 11 8 8 10 10 8 7 49 39 36 31 43 24 52 34 49 29 46 116 42 30 27 32 22 67 ___ .10 .09 .09 .11 .12 .21 .14 .14 .17 .14 .11 .09 6.5 1.3 1.1 .70 1.1 .34 4.1 .88 2.5 .59 2.6 56 1.7 .65 .46 .75 .53 10 ___ MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MAY MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) JUNE 134 111 21 12 8.6 8.3 7.5 6.9 140 36 12 7.0 4.5 5.0 6.7 3.1 2.3 3.8 2.3 1.4 1.8 1.3 2.8 2.6 5.3 4.7 40 35 14 11 8.8 172 151 53 39 21 22 30 28 171 91 48 28 21 24 34 17 14 19 14 13 12 9 15 14 23 22 67 81 45 35 26 165 59 2.7 1.3 .50 .50 .61 .52 175 11 1.7 .55 .27 .39 .65 .15 .09 .23 .08 .04 .06 .03 .18 .17 .33 .34 18 9.3 1.8 .99 .66 8 7 7 6 6 5 5 14 35 35 16 9 82 145 29 13 9 8 1290 417 55 33 24 19 16 13 12 11 10 18 .1 .5 .4 .8 .2 .6 .0 .8 .7 .6 30 49 60 62 60 58 53 50 79 80 67 58 111 199 78 58 53 55 657 363 103 77 63 55 47 41 33 22 18 54 .66 1.0 1.2 1.2 1.0 .87 .72 2.4 9.8 7.7 3.2 1.7 82 112 6.6 2.2 1.4 1.6 3500 629 18 6.8 4.3 3.0 2.0 1.4 1.0 .63 .48 2.8 TOTAL 330.7 93.31 660.7 452.14 2361.7 4406.66 RIO GRANDS DB LOIZA BASIN 50055750 RIO GURABO BELOW EL MANGO, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 277 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) JULY 13 21 94 31 15 11 40 93 20 12 1710 184 74 51 208 234 46 28 22 19 16 328 831 154 55 107 62 30 21 17 15 4562 ,58.8 36 54 138 78 47 46 90 152 56 39 640 159 122 105 177 258 97 68 58 53 49 280 531 132 88 153 125 96 85 45 66 —— 1.3 3.7 47 8.3 2.0 1.4 17 51 3.3 1.2 4800 101 30 16 386 248 13 5.2 3.5 2.8 2.2 739 1600 60 14 76 23 7.7 4.8 1.9 2.6 8272.9 21850.93 MEAN DISCHARGE (CFS) 14 12 11 11 10 9.8 9.1 8.6 8.0 7.8 7.8 7.8 7.4 6.9 7.0 11 11 7.6 6.4 6.3 6.0 5.5 25 28 23 10 7.6 7.6 6.7 6.5 9.1 315.5 MEAN CONCEN- TRATION (MG/L) AUGUST 61 58 54 49 51 54 56 53 50 49 50 50 51 48 38 39 37 29 27 37 48 39 64 72 70 37 31 30 29 27 39 ___ SEDIMENT DISCHARGE (TONS /DAY) 2.2 1.9 1.8 1.4 1.4 1.4 1.4 1.2 1.1 1.0 1.0 1.1 1.0 .91 .75 1.2 1.1 .58 .46 .63 .79 .63 5.8 7.7 4.9 1.1 .68 .62 .55 .48 1.0 47.78 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) SEPTEMBER 12 9.3 7.7 7.7 69 29 11 150 56 81 28 13 10 9.2 8.3 42 115 84 40 18 12 11 10 9.4 11 9.9 9.8 47 24 225 41 33 41 55 116 72 37 192 110 140 118 103 90 79 62 88 213 165 87 51 56 76 76 67 57 40 30 79 64 312 1.3 .85 .87 1.1 43 8.3 1.1 214 21 38 9.8 3.8 2.5 2.0 1.5 14 168 59 12 2.5 1.8 2.2 2.1 1.7 1.5 1.1 .85 31 5.9 432 1169.3 1084.77 272 RIO GRANGE DB LOIZA BASIN 50055750 RIO GURABO BELOW EL MANGO, PR—Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT DATE APR 1993 19... HAY 01. .. JUN 19... DATE APR 1993 19. .. HAY 01. .. JUN 19. .. TIME 0937 2003 0953 SBD. SDSP. FALL DIAM. PERCENT FINER THAN .016 MM 86 84 63 DIS- CHARGE, INST. CUBIC FEET PER SECOND 60 620 4750 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM 91 88 73 SEDI- MENT, SUS- PENDED (MG/L) 1340 1150 3380 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 98 99.7 83 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 217 1920 43300 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 98.6 98.8 90 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM 71 72 43 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 99.2 99.3 94 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM 80 75 50 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 99.8 99.6 97 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 82 80 51 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 100 100 99.6 RIO GRANDB DE LOIZA BASIN 50055750 RIO GURABO BELOW EL MANGO--Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 SILT AND CLAY PERCENT OP SUSPENDED SEDIMENT 273 DATE NOV 1992 15... 16.. . 16.. . 16... 28... JAN 1993 28.. . 29... 29... APR 24.. . MAY 01... 02.. . 09.. . 09... 11.. . TIME 1313 1315 1754 2017 0109 2326 0436 1135 1256 1813 0327 1607 1857 1725 STREAM- PLOW, INSTAN- TANEOUS (CPS) SEDI- MENT, SUS- PENDED (MG/L) SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 351 14 329 318 321 174 344 203 534 521 322 754 382 3.3 1180 125 233 1670 266 1650 246 74 627 478 227 848 422 48 1130 4.7 207 1430 231 775 228 41 907 672 197 1730 435 0.43 97 100 97 98 100 79 97 96 96 91 95 97 97 85 274 RIO GRANDB DB LOIZA BASIN 50056400 RIO VALENCIANO HEAR JUNCOS, PR LOCATION.--Lat 18«12'58", long 65«55'34", Hydrologic Unit 21010005, on left bank at Highway 919, 0.5 ml (0.8 km) upstream from Quebrada Don Victor, 1.7 ml (2.7 km) upstream from Rio Ourabo and 1.0 ml (1.6 km) south of Juncos. DRAINAGE AREA.--16.4 ml 1 (42.5 km1 ). 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 poor. Minor diversion from public water supply tank, 0.5 ml upstream, during low flow. and precipitation satellite telemetry at station. Gage-height EXTREMES OUTSIDE PERIOD OF Sept. 6, 1960, 37,100 ft3 RECORD.--Approximate discharges (no stages were recorded) of major floods are as follows: /s (1,050 mVs), Oct. 9, 1970, 18,200 ftVs (515 mVs) . DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 29 e!7 2 23 e!8 3 21 e44 4 20 e27 5 19 eSO 6 20 99 7 20 48 8 19 24 9 e!9 23 10 e!9 24 11 e!8 20 12 e!8 18 13 e!7 34 14 el7 19 15 e!7 50 16 e!7 34 17 el 9 34 18 el9 84 19 el 9 76 20 e20 35 21 20 27 22 24 32 23 20 25 24 22 22 25 e25 20 26 e!9 19 27 17 60 28 18 224 29 18 120 30 e20 1140 31 e23 TOTAL 616 2467 MEAN 19.9 82.2 MAX 29 1140 MIN 17 17 AC- FT 1220 4890 CFSM 1.21 5.01 IN. 1.40 5.60 STATISTICS OF MONTHLY MEAN MEAN 79.1 93.7 MAX 293 461 (WY) 1986 1988 MIN 19.9 19.5 (WY) 1993 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 73 49 50 81 48 45 34 30 29 26 25 23 23 23 23 21 21 20 20 20 20 20 19 22 25 130 39 26 116 148 219 1468 47.4 219 19 2910 2.89 3.33 DATA 58.6 550 1988 11.0 1990 FOR 92 58 45 49 36 37 72 44 40 35 29 28 26 34 26 26 25 25 23 22 20 22 24 20 23 20 24 26 61 29 24 1065 34.4 92 20 2110 2.09 2.42 22 47 36 23 22 20 20 19 19 18 19 20 e22 e20 e!8 el7 18 17 17 17 17 16 16 17 17 17 18 17 ... ... --- 566 20.2 47 16 1120 1.23 1.28 FOR WATER YEARS 1971 23.6 77.0 1992 11.4 1976 17.8 47.9 1984 7.21 1974 18 19 18 18 18 18 20 19 19 19 20 18 19 17 16 15 18 17 13 12 12 10 9.9 13 15 12 11 9.8 10 9.3 8.3 471.3 15.2 20 8.3 935 .93 1.07 - 1993 19.4 39.7 1973 7.01 1977 1992 CALENDAR YEAR 15999. 43. 1150 3. 3. 31730 2. 36. 67 18 6. 1 7 Jan 5 4 Apr 27 8 Apr 24 67 29 4 8.4 8.5 9.5 8.1 7.7 8.8 7.4 7.5 9.5 7.8 7.1 8.0 94 18 9.7 9.2 e!6 e9.6 e31 e!7 e29 e!4 e45 e!20 e25 e!4 ell e!6 e40 e90--- 706.8 23.6 120 7.1 1400 1.44 1.60 e240 e!90 e40 e!3 17 14 12 11 132 42 20 15 14 39 20 15 14 15 13 13 14 13 13 13 20 21 48 33 18 16 14 1112 35.9 240 11 2210 2.19 2.52 15 15 14 12 12 11 11 e!7 e61 e69 23 16 23 61 e28 e25 e!7 e!5 e820 e!06 e70 e58 e47 e38 e28 25 23 22 22 28 --- 1732 57.7 820 11 3440 3.52 3.93 22 28 86 30 21 19 21 35 20 17 1430 121 53 48 36 42 31 27 26 25 23 341 507 109 54 89 69 37 30 26 24 3447 111 1430 17 6840 6.78 7.82 22 20 19 19 20 19 18 18 17 18 16 15 14 13 14 32 17 14 13 13 12 15 48 42 32 16 13 17 13 13 18 590 19.0 48 12 1170 1.16 1.34 22 18 21 15 50 23 17 27 29 193 59 23 22 20 16 88 21 32 25 26 18 18 18 24 27 20 16 21 19 214 ... 1142 38.1 214 15 2270 2.32 2.59 , BY WATER YEAR (WY) 15.7 41.7 1985 5.82 1991 FOR 1993 15383. 42. 1430 7. 8. 9460 14. 30510 2. 34. 61 20 13 54.0 268 1985 5.02 1990 WATER YEAR 1 1 Jul 11 1 Apr 11 0 Apr 5 Nov 30 80 Nov 30 57 89 50.6 188 1979 6.21 1977 48.9 163 1981 5.36 1974 WATER 50. 121 17. 9100 1. 2. 40000 25. 1. 36500 3. 41. 73 19 7. 62.4 231 1979 15.5 1980 YEARS 1971 - 4 1 Dec 8 8 Jun 12 6 May 19 Dec 8 63 Dec 8 4 Apr 21 07 75 3 77.7 255 1979 10.8 1987 1993 1988 1990 1987 1990 1990 1987 1987 1988 e Estimated RIO GRAHDE DB LOIZA BASIN 50056400 RIO VALENCIANO NEAR JUNCOS, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORDS.— Water years 1983 to 1986 and water year 1989 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: October 1989 to September 1993. INSTROMANTATION.-- Automatic sediment sampler. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATION: Maximum daily mean, 1,600 mg/L Oct. 06, 1985; Minimum daily mean, 1 mg/L several days. 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 1993.-- SBDIMENT CONCENTRATION: Maximum daily mean, 1,780 mg/L July 11, 1993; Minimum daily mean, 2 mg/L several days. SEDIMENT LOADS: Maximum daily mean, 16,200 tons (14,700 tonnes) July 11, 1993; Minimum daily mean, 0.10 ton (0.09 tonne) several days. SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 275 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/DAY) OCTOBER MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) NOVEMBER MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) 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 29 30 31 TOTAL 29 23 21 20 19 20 20 19 e!9 e!9 e!8 e!8 e!7 e!7 e!7 e!7 el9 e!9 el9 e20 20 24 20 22 e25 e!9 17 18 18 e20 e23 616 2 2 2 2 2 2 2 2 2 3 3 3 4 8 13 11 7 7 7 13 18 22 15 13 44 26 21 21 20 19 17 .16 .12 .12 .10 .10 .10 .10 .10 e.13 e.16 e.14 e.17 e.18 e.36 e.59 e.50 e.36 e.36 e.36 e.84 1.2 1.6 .81 .89 e3.0 el. 3 .96 1.0 .95 el.O el.l e!7 el8 e44 e27 e50 99 48 24 23 24 20 18 34 19 50 34 34 84 76 35 27 32 25 22 20 19 60 224 120 1140 15 14 33 26 62 118 129 70 30 23 15 15 69 44 75 37 35 175 161 34 26 35 29 23 15 12 72 406 190 1340 e.69 e.66 e3.9 el. 9 e8.4 30 16 4.7 1.9 1.5 .84 .71 8.4 2.3 19 3.8 3.3 71 44 3.2 1.9 3.1 2.0 1.3 .82 .58 35 532 299 13700 73 49 50 81 48 45 34 30 29 26 25 23 23 23 23 21 21 20 20 20 20 20 19 22 25 130 39 26 116 148 219 98 59 61 119 63 54 22 11 11 13 16 18 18 17 16 15 14 13 12 12 12 15 15 19 37 338 45 24 241 258 635 20 7.9 9.2 31 9.0 6.9 2.1 .89 .83 .87 1.0 1.1 1.1 1.1 .98 .83 .75 .67 .60 .62 .68 .81 .74 1.1 2.4 360 5.3 1.6 132 139 936 18.86 2467 14801.90 1468 1677.07 e Estimated 276 RIO GRANDS DB LOIZA BASIN 50056400 RIO VALBNCIANO NR JONCOS, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 MEAN MEAN MEAN CONCBN- 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 92 58 45 49 36 37 72 44 40 35 29 28 26 34 26 26 25 25 23 22 20 22 24 20 23 20 24 26 61 29 24 166 85 54 60 36 35 113 55 18 13 12 10 10 31 30 21 18 14 13 13 11 17 23 17 21 18 16 23 116 91 54 44 14 6.7 8.6 3.5 3.5 31 7.2 1.9 1.3 .89 .77 .69 3.4 2.1 1.5 1.2 .96 .77 .73 .61 1.0 1.6 .94 1.4 1.0 1.1 1.6 21 7.3 3.5 FEBRUARY 22 47 36 23 22 20 20 19 19 18 19 20 e22 e20 e!8 e!7 18 17 17 17 17 16 16 17 17 17 18 17 ___ ___ 25 69 176 79 16 15 13 11 10 10 8 8 8 10 11 12 12 12 12 12 11 10 10 10 10 10 8 8 ___ -__ ___ 1.5 21 17 5.0 .93 .81 .66 .54 .52 .46 .44 .44 e.51 e.51 e.51 e.56 .57 .56 .56 .53 .47 .42 .43 .48 .44 .45 .39 .39 ___ MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MARCH 18 19 18 18 18 18 20 19 19 19 20 18 19 17 16 15 18 17 13 12 12 10 9.9 13 15 12 11 9.8 10 9.3 8.3 9 9 9 10 11 14 16 16 16 17 17 16 14 17 20 27 18 26 15 14 13 13 13 13 13 12 12 12 12 12 12 .44 .44 .43 .48 .55 .64 .79 .82 .82 .82 .87 .75 .75 .75 .88 1.1 1.1 1.3 .53 .44 .41 .36 .34 .39 .40 .38 .37 .32 .34 .31 .28 TOTAL 1065 175.76 566 57.08 471.3 18.60 e Estimated RIO GRANDE DE LOIZA BASIN 277 50056400 RIO VALENCIANO NR JUNCOS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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 (CPS) (HG/L) (TONS/DAY) 8.4 8.5 9.5 8.1 7.7 8.8 7.4 7.5 9.5 7.8 7.1 8.0 94 18 9.7 9.2 e!6 e9.6 e31 e!7 «29 e!4 e45 el20 e25 e!4 ell el6 e40 e90 APRIL 12 12 12 12 12 11 10 9 9 9 9 9 353 28 8 6 13 6 31 13 28 10 53 188 23 10 7 12 45 131 ___ MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (HG/L) (TONS/DAY) MAY .27 .27 .30 .26 .25 .26 .20 .18 .24 .18 .18 .20 298 1.8 .21 .20 e.88 e.16 e2.6 e.60 e2.2 e.38 e6.4 e61 el. 6 e.38 e.20 e.52 e4.9 e32 e240 e!90 e40 e!3 17 14 12 11 132 42 20 15 14 39 20 15 14 15 13 13 14 13 13 13 20 21 48 33 18 16 14 446 334 45 10 18 28 22 13 237 75 27 16 14 98 91 34 16 6 6 6 6 9 10 10 19 27 37 39 17 14 10 e289 el71 e4.9 e.34 .87 1.0 .73 .41 291 12 1.4 .77 .51 17 5.0 1.4 .60 .25 .22 .21 .26 .33 .36 .37 1.3 1.7 9.3 4.1 .84 .59 .37 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (HG/L) (TONS/DAY) JUNE 15 15 14 12 12 11 11 e!7 e61 e69 23 16 23 61 e28 e25 el7 elS e820 e!06 e70 eS8 e47 e38 e28 25 23 22 22 28 8 7 6 7 10 12 14 17 93 101 20 14 19 121 30 26 20 16 1100 162 54 45 40 37 31 24 18 10 3 20 ___ .31 .32 .25 .26 .33 .37 .43 e.78 e41 e27 1.2 .61 1.3 30 e2.5 el. 8 e.93 e.67 e4560 eS4 ell e7.1 eS.l e3.8 e2.4 1.6 1.1 .62 .19 1.7 TOTAL 706.8 416.82 1112 818.13 1732 4758.67 e Estimated 278 RIO GRANDB DE LOIZA BASIN 50056400 RIO VALBNCXANO NR JUNCOS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 MEAN DISCHARGE DAY (CFS) 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 YEAR 22 28 86 30 21 19 21 35 20 17 1430 121 53 48 36 42 31 27 26 25 23 341 507 109 54 89 69 37 30 26 24 3447 15383.1 MEAN MEAN CONCBN- SEDIMENT MEAN CONCBN- SEDIMENT TRATION DISCHARGE DISCHARGE TRATION DISCHARGE (MG/L) (TONS/DAY) (CPS) (MG/L) (TONS/DAY) JULY 19 29 130 33 18 12 6 35 17 14 1780 153 54 55 39 33 16 16 17 17 18 756 934 140 69 135 115 37 18 14 11 —— AUGUST 1.1 2.6 46 3.0 1.0 .57 .36 3.7 .91 .66 16200 69 7.9 7.1 3.8 4.1 1.3 1.1 1.2 1.1 1.0 1970 2180 45 11 59 25 3.9 1.4 .90 .68 20654.38 45108.94 22 20 19 19 20 19 18 18 17 18 16 15 14 13 14 32 17 14 13 13 12 15 48 42 32 16 13 17 13 13 18 590 8 7 7 7 6 4 3 3 3 3 3 4 4 4 5 32 15 14 13 12 12 14 100 82 57 12 10 12 9 8 8 —— .50 .38 .35 .34 .29 .22 .16 .13 .12 .16 .14 .17 .16 .16 .20 3.3 .75 .51 .46 .41 .37 1.0 14 11 5.7 .55 .35 .62 .32 .29 .37 43.48 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) SEPTEMBER 22 18 21 15 50 23 17 27 29 193 59 23 22 20 16 88 21 32 25 26 18 18 18 24 27 20 16 21 19 214 19 15 18 11 65 23 13 27 31 367 118 20 19 17 12 311 19 36 25 22 15 10 10 103 73 17 11 21 12 376 1.2 .90 1.1 .45 15 1.6 .61 3.3 3.1 486 28 1.3 1.2 1.0 .53 175 1.2 5.3 2.1 1.8 .72 .50 .56 6.9 5.3 1.0 .47 1.4 .65 920 1142 1668.19 RIO QRANDE DE LOIZA BASIN 50056400 RIO VALENCIANO NEAR JUNCOS, PR—Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 PARTICLE-SIZE DISTRIBUTION OP SUSPENDED SEDIMENT 279 DATE DEC 1992 26... 31... APR 1993 13. .. JUN 19... JUL 22... TIME 1435 0735 1515 0900 1810 DIS- CHARGE, INST. CUBIC FEET PER SECOND 464 803 446 3400 597 SEDI- MENT, SUS- PENDED (MG/L) 4020 7450 1640 8990 7540 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 504 16200 1970 82500 12200 SED. SUSP. PALL DIAM. PERCENT FINER THAN .002 MM 44 37 54 36 38 SED. SUSP. PALL DIAM. PERCENT FINER THAN .004 MM 55 43 64 42 43 SED. SUSP. PALL DIAM. PERCENT FINER THAN .008 MM 61 51 70 49 49 DATE DEC 1992 26... 31. .. APR 1993 13. .. JUN 19. .. JUL 22... SED. SUSP. FALL DIAM. PERCENT FINER THAN .016 MM 74 64 79 64 56 SBD. SUSP. PALL DIAM. PERCENT FINER THAN .031 MM 81 77 80 76 69 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 94 91 92 88 86 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 98 96 97 94 96 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 99 98 99 97 99 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 99.7 99.2 99.8 98 99.6 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 99.9 99.7 99.9 99.5 99.9 280 RIO GRANDE OB LOIZA BASIN 50056400 RIO VALBNCIANO NEAR JXJNCOS, PR--Continued HATER QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT DATE OCT 1992 20... NOV 18.. . 19... 27... 27... DEC 26... 29... 31.. . 31... FEB 1993 03... ABR 13... 13.. . MAY 09... 15.. . JUL 03... 22... TIME 1656 1945 0105 2000 2220 1415 1007 0705 1225 1650 1600 1740 1630 0737 1513 2130 STREAM- FLOW, INSTAN- TANEOUS (CFS) 21 188 197 214 235 212 110 256 238 28 585 285 933 20 163 686 SEDI- MENT, SUS- PENDED (MG/L) 958 342 374 383 341 6210 361 1240 679 162 1510 1320 1550 104 575 998 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 54 173 199 221 216 3550 107 857 436 12 2380 1010 3900 5.6 253 1850 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 100 90 98 97 98 77 92 97 99 96 95 99 95 97 99 94 RIO GRANDB DB LOIZA BASIN 50057000 RIO GURABO AT GURABO, PR LOCATION.—Lat 18°15'30", long 65°58'05", 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. 281 DRAINAGE AREA.--60.2 mi* (155.9 km'). WATBR-DISCHARGB RECORDS PERIOD OF RECORD.—1958 (occasional low-flow measurements only), January to September 1959 (monthly measurements only), October 1959 to current year. GAGB.—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 except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. Minimun daily discharge used due to temporary regulation of flow during construction of pond upstream from station by A.A.A. 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, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 52 81 2 45 61 3 26 86 4 21 202 5 20 136 6 31 121 7 81 180 8 44 88 9 46 76 10 36 177 11 37 93 12 31 70 13 27 92 14 29 73 15 29 130 16 30 167 17 40 205 18 61 515 19 59 271 20 71 147 21 62 120 22 60 173 23 50 146 24 51 93 25 73 85 26 55 76 27 50 240 28 47 985 29 66 213 30 55 2230 31 70 TOTAL 1455 7332 MEAN 46.9 244 MAX 81 2230 MIN 20 61 AC-FT 2890 14540 CFSM .78 4.06 IN. .90 4.53 STATISTICS OF MONTHLY MEAN MEAN 204 209 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 226 151 124 154 128 144 112 87 78 71 67 63 60 62 64 60 59 57 55 51 50 52 54 53 72 481 169 85 269 763 379 4300 139 763 50 8530 2.30 2.66 DATA 163 863 1988 10.7 1968 FOR 184 125 113 106 85 96 134 144 91 85 71 66 60 62 60 54 56 50 46 45 40 43 68 44 44 51 39 69 360 84 58 2633 84.9 360 39 5220 1.41 1.63 46 53 114 58 48 42 39 41 43 40 40 47 54 43 36 35 e35 e35 e36 e33 e33 e34 e32 e32 e32 e33 e32 e32 ___ ___ 1178 42.1 114 32 2340 .70 .73 FOR WATER YEARS 1960 63.4 204 1992 16.4 1968 46.2 131 1989 12.6 1968 e32 e30 e30 e30 e30 e28 e28 e30 e30 e30 e29 e30 e29 e29 e29 e30 e56 e60 e40 e38 e40 e30 e28 e56 e54 036 033 e30 e28 026 026 1055 34.0 60 26 2090 .57 .65 - 1993 39.9 97.5 1985 11.2 1965 1992 CALENDAR YEAR 44901.0 123 2470 7.3 12 89060 2.04 27.75 227 50 21 Jan 6 Apr 29 Apr 24 e26 025 024 e25 e25 e43 e33 e33 039 034 e26 027 100 91 115 62 48 29 78 60 56 35 39 115 77 39 025 070 0130 0250 —— 1779 59.3 250 24 3530 .99 1.10 , BY WATER 42.8 93.9 1985 15.8 1967 e450 e400 e26 e34 e23 e21 e21 e240 e60 e40 e27 050 e76 040 e27 e29 e25 e25 027 025 025 025 e30 36 43 70 86 127 48 31 25 2212 71.4 450 21 4390 1.19 1.37 YEAR (WY) 152 746 1985 12.7 1990 24 e25 e25 e23 e20 e20 el9 e20 74 121 59 32 36 216 99 64 37 29 2030 991 157 105 80 69 58 51 47 43 31 57 —— 4662 155 2030 19 9250 2.58 2.88 137 468 1970 16.8 1972 FOR 1993 WATER YEAR 42089 115 6200 19 22 17200 23.77 83480 1.92 26.01 161 52 27 Jul 11 Jun 7 Jun 2 Jul 11 Jul 11 46 64 196 93 48 37 46 126 74 41 6200 428 144 117 104 334 106 80 69 67 57 681 1390 335 149 159 165 94 76 67 62 11655 376 6200 37 23120 6.25 7.20 125 376 1993 20.9 1967 WATER 133 286 42. 21100 4. 5. 21100 27. 4. 96680 2. 30. 213 50 19 57 54 50 46 45 45 40 38 36 36 34 34 30 29 31 57 48 33 29 28 27 58 94 80 80 52 45 37 31 28 34 1366 44.1 94 27 2710 .73 .84 173 610 1979 24.8 1967 YEARS 1960 - 2 Sep 6 8 Sep 26 5 Sep 21 Sep 6 70 Sep 6 5 Feb 21 22 12 45 37 37 27 74 88 38 118 125 156 136 48 35 36 30 92 112 138 114 117 63 42 41 46 38 57 40 51 103 378 —— 2462 82.1 378 27 4880 1.36 1.52 224 1225 1960 8.76 1967 1993 1979 1967 1960 1967 1967 1960 1960 1968 282 RIO GRANDB DE LOIZA BASIN 50057025 RIO GURABO NEAR GURABO, PR WATER-QUALITY RBCORDS LOCATION.--Lat 18°15'56", long 65°59'04", at bridge on Highway 941, 1.2 mi (1.9 km) west-northwest from gaging station 50057000, and 1.0 mi (1.6 km) northwest of Gurabo plaza. DRAINAGE AREA.--62.8 mi» (162.7 km3 ). PERIOD OF RECORD.—Water years 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 07. .. DEC 04... FBB 1993 10... APR 12... MAY 25... AUG 05... TIME 1030 0900 1310 1030 1145 0800 SPE- CIFIC CON- DUCT- ANCE (US/CM) 300 299 403 285 414 390 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.2 6.9 7.6 7.2 7.1 7.0 TEMPER- ATURE WATER (DEG C) 29.0 25.7 27.0 27.5 29.2 28.6 TUR- BID- ITY (NTU) 26 6.3 11 14 8.7 1.0 OXYGEN, DIS- SOLVED (MG/L) 3.5 4.1 4.8 2.8 1.7 4.5 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 45 51 60 35 21 57 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 17 13 21 19 24 15 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 20000 4500 20000 K6500 2300 K900 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 2100 550 380 21000 K180 200 DATE OCT 1992 07... DEC 04... FEB 1993 10... APR 12... MAY 25... AUG 05... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MG/L TOT FLD SOLVED AS MG/L AS (MG/L CACO3) CACO3 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS NA) 44 0 26 12 32 140 7 31 15 36 130 4 30 13 30 SODIUM AD- SORP- TION RATIO POTAS- SIUM, DIS- SOLVED (MG/L AS K) 3.9 4.6 4.2 ALKA- LINITY WAT WH TOT FET SULFIDE FIELD TOTAL MG/L AS (MG/L CACO3 120 130 130 140 140 140 CHLO- SULFATE RIDE, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS S) AS SO4) AS CL) 0.6 13 <0.5 21 19 28 38 27 SOLIDS, DATE OCT 1992 07.. . DEC 04... FEB 1993 10... APR 12... MAY 25... AUG 05... FLUO- RIDE, DIS- SOLVED (MG/L AS F) <0.10 -- -- 0.20 -- 0.20 SILICA, DIS- SOLVED (MG/L AS SIO2) 14 -- — 35 — 31 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 93 -- -- 265 -- 234 RESIDUE SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, SOLVED DEG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC (TONS SUS- 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) 36 14 19 26 22 3 0.750 0.440 0.250 1.30 0.750 0.440 0.050 0.060 0.150 0.100 0.050 0.060 0.800 0.500 0.400 1.40 0.800 0.500 0.180 0.670 0.360 0.540 0.610 0.670 0.42 0.23 1.7 0.26 0.69 0.23 K = non-ideal count DATE OCT 1992 07... DEC 04... FEB 1993 10... APR 12... HAY 25... AUG OS... DATE OCT 1992 07... DEC 04... FBB 1993 10... APR 12... HAY 25... AUG 05.. . RIO QRANDE DE LOIZA BASIN S0057025 RIO GDRABO NEAR GURABO, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 283 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.60 0.90 2.1 0.80 1.8 1.1 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) 1.4 1.8 2.5 2.2 3.5 2.5 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N03) 6.2 7.3 11 9.7 15 11 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.330 0.260 0.410 0.670 0.540 0.290 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) ARSENIC TOTAL (UG/L AS AS) 2 -- — 2 -- -- SELE- NIUM, TOTAL (UG/L AS SB) BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) 200 — - <100 -- -- SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) 40 -- -- 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) 9 -- -- <1 -- -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) 40 — -- 10 -- -- MBTHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 990 980 270 540 <0.10 <0.10 10 <0.010 <0.010 0.05 0.06 284 RIO GRANDS 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 Vald6», and .8 mi (1.3 km) north of La Barra. DRAINAGE AREA.--7.53 mi» (19.50 km'). WATBR-DISCHARGB RECORDS PERIOD OF RECORD.--March 1990 to current year. GAGE.--Water-stage recorder and crest-stage gage. Elevation of gage is 164 ft (50 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 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES OCT NOV DBC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 3.5 4.2 2 2.8 2.6 3 2.7 6.9 4 2.7 77 5 6.8 17 6 8.3 6.2 7 4.2 4.6 8 47 4.1 9 24 4.6 10 153 4.1 11 39 2.9 12 9.8 3.4 13 6.0 5.4 14 23 14 15 6.8 5.8 16 5.7 3.6 17 6.2 9.7 18 43 32 19 16 8.0 20 6.2 25 21 5.1 9.0 22 7.5 61 23 3.6 9.9 24 4.4 19 25 3.7 3.9 26 2.7 3.6 27 2.6 257 28 2.5 252 29 2.2 67 30 3.7 162 31 7.2 TOTAL 461.9 1085.5 MEAN 14.9 36.2 MAX 153 257 KIN 2.2 2.6 AC-PT 916 2150 CFSM 1.98 4.81 IN. 2.28 5.36 44 30 23 20 14 12 9.8 9.4 9.2 8.1 7.2 6.2 5.9 43 28 6.9 8.4 8.8 13 7.8 7.3 19 8.S 39 38 215 60 74 67 42 42 926.5 29.9 215 5.9 1840 3.97 4.58 STATISTICS OF MONTHLY MEAN DATA MEAN 19.6 17.1 MAX 39.4 36.2 (WY) 1991 1993 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 INSTANTANEOUS LOW FLOW ANNUAL RUNOFF (AC- FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 15.9 29.9 1993 5.78 1992 FOR 16 17 13 9.1 18 16 25 13 8.5 7.6 6.7 7.2 7.2 7.2 6.7 6.7 7.1 6.1 5.7 6.2 6.2 18 13 8.4 13 9.1 8.7 8.2 12 8.5 8.8 323.9 10.4 25 5.7 642 1.39 1.60 9.1 9.1 12 7.9 7.8 7.8 7.2 7.1 6.7 7.2 7.3 9.0 8.8 7.8 8.5 26 9.6 7.4 7.4 7.2 7.2 6.6 5.3 5.3 5.2 4.9 4.9 4.5 ___ ___ — - 224.8 8.03 26 4.5 446 1.07 1.11 FOR WATER YEARS 1990 13.9 24.5 1992 6.76 1991 9.68 13.2 1991 7.91 1992 .3 .8 .9 .9 .9 .9 .9 .7 .4 .0 3.8 3.8 3.7 3.5 3.5 4.9 4.5 4.4 4.0 3.8 3.7 3.5 3.9 9.4 5.8 5.5 5.9 4.8 4.1 3.8 3.1 140.1 4.52 9.4 3.1 278 .60 .69 - 1993 5.40 5.88 1992 4.52 1993 1992 CALENDAR YEAR 5751.8 15.7 266 2.2 2.6 11410 2.09 28.42 32 6.2 3.2 Aug 9 Jul 27 Jul 25 3.3 3.8 3.8 3.8 3.8 3.5 3.6 36 16 6.8 18 15 37 11 6.3 6.3 4.3 3.7 3.5 27 14 7.7 5.8 4.7 4.0 5.1 18 14 29 15--- 333.8 11.1 37 3.3 662 1.48 1.65 53 67 9.0 4.4 14 5.4 4.5 7.0 15 8.2 5.8 4.0 3.2 55 12 7.7 5.9 5.5 5.2 5.4 5.7 5.6 11 6.2 7.0 81 42 57 19 12 10 553.7 17.9 81 3.2 1100 2.37 2.74 9.8 9.8 7.4 6.2 6.2 6.2 6.2 27 68 30 15 11 10 38 26 15 6.3 7.1 134 70 22 11 8.2 6.4 5.5 4.9 4.9 11 12 6.4 601.5 20.0 134 4.9 1190 2.66 2.97 4.9 5.5 6.8 5.1 3.9 3.8 99 41 33 31 236 48 18 12 12 9.4 7.0 7.9 6.7 5.3 5.2 16 48 36 15 21 12 7.3 6.0 5.3 5.3 773.4 24.9 236 3.8 1530 3.31 3.82 .9 .1 .1 .1 .1 4.0 3.7 3.5 16 4.2 3.4 4.1 3.7 3.6 3.4 19 4.6 3.9 3.5 3.4 3.2 6.1 5.3 3.4 3.2 4.4 6.3 4.2 3.3 3.2 3.1 151.0 4.87 19 3.1 300 .65 .75 2.9 2.9 3.0 7.4 5.6 17 4.6 2.9 3.3 2.8 8.1 2.9 2.8 2.8 3.4 3.9 2.9 47 17 34 e3.5 e3.0 e4.2 e3.2 e3.0 e3.1 e2.9 e5.8 11 20 236.9 7.90 47 2.8 470 1.05 1.17 , BY WATER YEAR (WY) 5.93 11.1 1993 3.53 1990 FOR 1993 5813. 15. 257 2. 3. 1700 16. 2. 11530 2. 28. 37 6. 3. 12.5 19.5 1992 3.32 1990 WATER YEAR 0 9 Nov 27 2 Oct 29 1 Oct 23 Nov 28 44 Nov 28 0 Oct 28 12 72 8 4 10.8 20.0 1993 4.06 1990 12.1 24.9 1993 3.40 1990 WATER 12. 15. 10. 292 2. 2. 3830 20. 2. 9120 1. 22. 19 5. 3. 8.39 17.2 1992 4.36 1990 YEARS 1990 - 6 9 5 Oct 17 2 Jul 27 6 Jul 25 Oct 17 55 Oct 17 0 Oct 28 67 72 4 3 8.19 12.9 1992 5.62 1991 1993 1993 1992 1990 1992 1992 1990 1990 1992 RIO GRANDE DE LOIZA BASIN 50058350 RIO CANAS AT RIO CANAS, PR—Continued WATER-QUALITY RECORDS PERIOD OF RECORDS.-- Water years 1990 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: March 1990 to September 1993. INSTRUMENTATION.-- Automatic sediment sampler. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATION: Maximum daily mean, 2,470 mg/L Nov. 27, 1992; Minimum daily mean, 1 mg/L September 11,1991 SEDIMENT LOADSi 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 CONCENTRATIONi Maximum daily mean, 2,470 mg/L Nov. 27, 1992; Minimum daily mean, 4 mg/L several days. SEDIMENT LOADSi Maximum daily mean, 4,100 tons (3,720 tonnes) Nov. 28, 1992; Minimum daily mean, 0.03 ton (0.03 tonne) several days. 285 SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) NOVEMBER 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 (CFS) 3.5 2.8 2.7 2.7 6.8 8.3 4.2 47 24 153 39 9.8 6.0 23 6.8 5.7 6.2 43 16 6.2 5.1 7.5 3.6 4.4 3.7 2.7 2.6 2.5 2.2 3.7 7.2 461.9 MEAN CONCEN- TRATION (MG/L) OCTOBER 11 11 11 11 29 27 32 381 113 1340 201 28 14 108 31 28 28 265 66 23 20 20 20 16 12 12 12 11 10 12 26 ___ SEDIMENT DISCHARGE (TONS/ DAY) .11 .08 .08 .08 2.2 1.1 .39 207 16 2240 32 .84 .23 19 .61 .40 .54 101 4.6 .36 .26 .42 .20 .17 .13 .09 .08 .07 .06 .15 .57 2628.82 4.2 2.6 6.9 77 17 6.2 4.6 4.1 4.6 4.1 2.9 3.4 5.4 14 5.8 3.6 9.7 32 8.0 25 9.0 61 9.9 19 3.9 3.6 257 252 67 162 11 15 51 615 100 23 15 13 11 10 9 9 16 62 18 8 35 164 26 143 39 336 31 91 9 9 2470 1720 205 970 .15 .11 7.3 208 7.0 .38 .19 .14 .13 .10 .08 .15 .36 9.6 .70 .09 2.1 32 .80 44 1.3 108 1.3 13 .09 .08 3990 4100 42 1260 MEAN DISCHARGE (CFS) 44 30 23 20 14 12 9.8 9.4 9.2 8.1 7.2 6.2 5.9 43 28 6.9 8.4 8.8 13 7.8 7.3 19 8.5 39 38 215 60 74 67 42 42 MEAN CONCEN- TRATION (MG/L) DECEMBER 43 34 31 27 22 18 16 16 18 29 45 53 42 279 142 24 22 24 56 20 20 78 30 192 200 1630 333 436 473 139 194 SEDIMENT DISCHARGE (TONS/DAY) 5.4 2.8 1.9 1.3 .90 .56 .45 .41 .41 .60 .83 .88 .67 124 27 .45 .53 .79 2.9 .42 .39 6.4 .68 38 40 2610 60 161 260 20 29 1085.5 9829.15 926.5 3398.67 RIO GRANDB DB LOIZA BASIN 50058350 RIO CANAS AT RIO CANAS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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 16 17 13 9.1 18 16 25 13 8.5 7.6 6.7 7.2 7.2 7.2 6.7 6.7 7.1 6.1 5.7 6.2 6.2 18 13 8.4 13 9.1 8.7 8.2 12 8.5 8.8 57 60 28 19 83 71 108 31 13 12 11 11 11 11 10 8 8 8 8 8 9 70 46 20 44 34 34 27 19 7 5 2.7 3.6 1.0 .47 13 7.4 12 1.4 .29 .23 .20 .21 .22 .20 .17 .16 .15 .13 .13 .14 .16 9.2 2.8 .44 2.7 .92 .79 .61 .62 .17 .11 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) FEBRUARY 9.1 9.1 12 7.9 7.8 7.8 7.2 7.1 6.7 7.2 7.3 9.0 8.8 7.8 8.5 26 9.6 7.4 7.4 7.2 7.2 6.6 5.3 5.3 5.2 4.9 4.9 4.5 5 5 5 7 8 8 8 8 9 10 11 15 17 14 10 117 35 23 20 20 20 20 20 19 16 11 10 15 .12 .12 .17 .15 .16 .16 .16 .16 .16 .18 .24 .41 .43 .28 .25 21 1.1 .44 .38 .38 .38 .36 .28 .27 .22 .15 .13 .18 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MARCH .3 .8 .9 .9 .9 .9 .9 .7 .4 .0 3.8 3.8 3.7 3.5 3.5 4.9 4.5 4.4 4.0 3.8 3.7 3.5 3.9 9.4 5.8 5.5 5.9 4.8 4.1 3.8 3.1 22 28 30 25 15 7 7 10 10 10 10 11 13 14 14 14 13 11 7 5 5 7 9 32 28 25 28 30 33 39 41 .26 .35 .40 .33 .20 .10 .09 .12 .12 .11 .10 .11 .13 .14 .14 .17 .16 .13 .09 .06 .06 .07 .11 2.1 .47 .35 .42 .40 .36 .39 .35 TOTAL 323.9 62.32 224.8 28.42 140.1 8.39 RIO GRANDE DB LOIZA BASIN 50058350 RIO CANAS AT RIO CANAS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 287 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 3.3 3.8 3.8 3.8 3.8 3.5 3.6 36 16 6.8 18 15 37 11 6.3 6.3 4.3 3.7 3.5 27 14 7.7 5.8 4.7 4.0 5.1 18 14 29 15 ___ APRIL 25 9 8 8 8 8 8 237 64 17 80 59 209 37 11 8 7 7 7 135 49 36 24 14 7 11 82 58 146 129 ___ MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MAY .22 .09 .08 .08 .08 .08 .08 109 5.2 .40 9.2 7.4 68 1.5 .17 .15 .09 .07 .06 24 2.4 .80 .37 .17 .08 .45 11 5.6 25 5.8 ___ 53 67 9.0 4.4 14 5.4 4.5 7.0 15 8.2 5.8 4.0 3.2 55 12 7.7 5.9 5.5 5.2 5.4 5.7 5.6 11 6.2 7.0 81 42 57 19 12 10 370 403 25 10 81 87 83 83 130 98 90 89 88 376 38 19 16 15 15 15 15 15 38 21 19 711 194 377 44 27 25 142 131 .81 .13 8.9 1.3 .96 1.7 6.5 2.2 1.4 .97 .76 147 1.5 .38 .25 .23 .21 .22 .24 .24 2.4 .36 .34 724 23 210 2.8 .86 .70 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) JUNE 9. 9. 7. 6. 6. 6. 6. 27 68 30 15 11 10 38 26 15 6. 7. 134 70 22 11 8. 6. 5. 4. 4. 11 12 6. 8 8 4 2 2 2 2 3 1 2 4 5 9 9 4 23 17 15 16 16 16 16 138 520 143 56 31 31 227 127 61 17 25 880 419 73 33 20 20 20 19 17 132 43 21 .59 .45 .30 .26 .26 .26 .26 26 460 16 2.7 .86 .86 83 20 3.9 .30 2.1 384 125 4.2 1.1 .43 .33 .28 .25 .23 17 2.2 .38 TOTAL 333.8 277.62 553.7 1413.36 601.5 1153.50 oop £OV RIO GRANDB DB LOIZA BASIN 50058350 RIO CANAS AT RIO CANAS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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 TOTAL YEAR 4.9 5.5 6.8 5.1 3.9 3.8 99 41 33 31 236 48 18 12 12 9.4 7.0 7.9 6.7 5.3 5.2 16 48 36 15 21 12 7.3 6.0 5.3 5.3 773.4 5813.0 MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) JULY 15 12 12 12 12 12 1200 202 141 128 2060 245 53 10 27 27 15 15 15 15 15 67 267 172 55 94 37 13 10 10 10 —— MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AUGUST .20 .17 .20 .18 .13 .12 1810 25 13 11 2480 40 3.2 .33 1.5 .76 .28 .30 .26 .22 .21 6.2 55 27 3.0 11 1.5 .25 .15 .14 .14 4491.44 23935.57 4.9 4.1 4.1 4.1 4.1 4.0 3.7 3.5 16 4.2 3.4 4.1 3.7 3.6 3.4 19 4.6 3.9 3.5 3.4 3.2 6.1 5.3 3.4 3.2 4.4 6.3 4.2 3.3 3.2 3.1 151.0 10 10 10 10 10 11 13 12 80 20 15 15 14 13 12 97 50 37 25 15 9 18 17 11 10 10 18 8 7 5 4 ... .13 .12 .11 .11 .11 .12 .12 .11 16 .24 .15 .16 .13 .14 .11 7.1 .67 .38 .23 .13 .07 .58 .30 .09 .08 .11 .77 .09 .07 .05 .04 28.62 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) SEPTEMBER 2.9 2.9 3.0 7.4 5.6 17 4.6 2.9 3.3 2.8 8.1 2.9 2.8 2.8 3.4 3.9 2.9 47 17 34 e3.5 e3.0 e4.2 e3.2 e3.0 e3.1 e2.9 e5.8 11 20--- 236.9 4 4 4 25 16 92 13 6 6 6 33 7 6 6 10 9 6 833 61 199 73 24 11 10 9 8 7 40 38 88 --- —— .03 .03 .03 2.0 .39 32 .24 .04 .05 .05 4.3 .06 .05 .05 .27 .11 .04 485 3.3 67 e.69 e.19 e.12 e.08 e.08 e.07 e.05 e.64 1.3 17 --- 615.26 e Estimated RIO GRANDEE DE LOIZA BASIN 50058350 RIO CANAS AT CANAS, PR—Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 PARTICLE-SIZE DISTRIBUTION OP SUSPENDED SEDIMENT 289 DATE OCT 1992 08. .. DEC 26... MAY 1993 05... JUL 07. .. SEP 16... DATE OCT 1992 08... DEC 26... MAY 1993 05... JUL 07.. . SEP 16.. . TIME 1635 1520 1520 1325 1717 SED. SUSP. FALL DIAM. PERCENT FINER THAN .016 MM 45 51 81 60 81 DIS- CHARGE, INST. CUBIC FEET PER SECOND 359 295 48 961 53 SED. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM 58 57 83 68 89 SEDI- MENT, SUS- PENDED (MG/L) 16200 3230 4570 20500 14900 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 76 67 99 83 99 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 15700 2570 592 53100 2140 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 88 77 99.5 90 99.8 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM 25 37 55 37 47 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 97 87 99.7 94 99.9 SED. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM 28 41 63 45 57 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 99 91 99.8 97 100 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 36 44 73 48 67 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 100 93 100 99 100 290 RIO GRANDB DB LOIZA BASIN 50058350 RIO CANAS AT CANAS, PR—Continued HATER QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT DATE OCT 1992 08... 14... NOV 27... DEC 26... APR 1993 10... 21... JUN 15. .. JUL 07. .. 11. .. TIME 1755 1718 1100 0215 0818 1735 1600 1445 1415 STREAM- FLOW, INSTAN- TANEOUS (CFS) 172 82 586 224 140 27 13 411 615 SEDI- MENT, SUS- PENDED (MG/L) 2310 805 5610 1900 6.8 656 2990 8410 1770 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 1070 178 8880 1150 2.6 48 105 9330 2940 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 98 97 57 88 96 99 21 99 91 291 RIO QRANDE DE LOIZA BASIN 50059000 LAGO LOIZA AT DAMSITE, PR LOCATION.--Lat 18°19'49", long 66°01'00", Hydrologic Unit 21010005, at pumpsite at damsite, and 1.9 mi (3.1 km) south of Trujillo Alto plaza. DRANAIQE AREA.--208 mi 1 (539 km1 ). ELEVATION RECORDS PERIOD OF RECORD.--December 1987 to current year. GAGE.—Hater-stage recorder. Datum of gage is mean sea 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 slide 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.—Maximum elevation 147.42 ft (44.93 m), Sept. 18, 1989; minimum elevation, 125.86 ft (38.36 m), June 12, 1988. EXTREMES FOR CURRENT YEAR.--Maximum elevation 134.88 ft (41.11 m), May 14; minimum elevation, 127.06 ft (38.73 m), Apr. 8. 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 98.4 5,000 128.6 18,000 111.5 8,900 137.8 26,000 120.4 13,000 147.6 35,000 ELEVATION (FEET NGVD), HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY OBSERVATION AT 24:00 VALUES DAY OCT NOV DEC JAN FEE MAR APR MAY JUN JUL AUG SEP 1 133.15 133.28 133.08 133.28 134.33 133.51 128.83 133.47 133.72 134.05 133.61 133.72 2 133.25 133.26 132.58 132.73 133.71 133.43 128.51 133.33 133.64 133.53 133.00 132.48 3 133.29 133.52 133.35 133.41 134.06 133.32 128.27 134.25 133.53 133.55 133.20 132.64 4 133.32 133.61 133.00 132.79 134.14 133.17 128.01 134.45 133.41 133.96 133.34 132.72 5 133.34 133.26 132.92 133.25 134.18 133.03 127.74 134.15 133.29 134.06 133.50 133.22 6 133.62 132.97 133.10 133.68 134.22 132.92 127.48 134.03 133.11 134.08 132.92 132.78 7 133.40 133.10 133.03 133.63 134.24 132.74 127.24 134.17 132.96 133.64 133.02 132.92 8 133.08 133.30 133.13 133.09 134.24 132.61 127.20 134.21 133.01 133.62 133.16 133.28 9 133.30 133.39 133.13 133.51 134.22 132.46 127.24 134.01 133.45 133.68 133.30 132.84 10 133.00 133.60 133.13 132.97 134.24 132.30 127.24 133.97 133.67 133.32 133.40 133.66 11 133.15 133.12 133.13 133.22 134.24 132.12 127.16 134.14 133.71 132.57 133.48 132.82 12 133.21 133.20 133.13 133.45 134.30 131.92 127.18 134.20 133.65 133.87 133.58 132.96 13 133.21 133.35 133.13 133.62 134.40 131.74 127.78 134.18 133.57 132.83 133.62 133.04 14 133.28 133.49 133.13 133.83 134.42 131.60 128.21 134.00 133.79 132.85 132.76 133.12 15 133.26 133.03 133.21 133.96 134.40 131.42 130.65 133.98 133.69 132.84 132.83 133.20 16 133.24 133.41 133.35 134.09 134.42 131.32 130.97 134.20 134.27 133.00 133.27 133.70 17 133.21 133.55 133.48 133.70 134.38 131.20 130.99 134.28 134.35 132.94 132.99 133.04 18 133.55 132.83 132.97 133.78 134.31 131.12 130.89 134.32 133.96 133.28 133.25 132.86 19 133.31 133.68 133.02 133.88 134.23 131.02 130.90 133.82 133.73 132.86 133.39 133.48 20 133.34 133.54 133.10 133.97 134.19 130.94 131.02 133.82 134.02 133.10 133.49 133.10 21 133.50 132.92 133.14 134.01 134.15 130.82 131.18 133.80 133.73 133.25 133.55 133.32 22 133.32 132.96 133.46 133.17 134.09 130.62 131.12 133.76 133.68 132.97 133.37 133.40 23 133.31 133.44 132.86 133.53 134.01 130.51 130.98 133.96 134.22 133.33 133.11 132.86 24 133.31 132.68 133.10 133.65 133.93 130.45 131.00 134.02 133.73 132.77 133.63 133.58 25 133.61 132.90 133.47 133.99 133.79 130.29 130.96 134.06 133.94 133.35 132.97 132.62 26 27 28 29 30 31 133.30 133.28 133.28 133.27 133.27 133.27 133.02 132.78 132.90 133.05 132.80 132.97 133.13 132.72 133.58 132.68 133.28 134.15 133.47 133.73 133.71 134.05 134.19 133.77 133.71 133.57 ___ 13 0 . 13 12 9 . 97 129.79 12 9 . 55 129.33 129.09 130.86 131.05 131.17 132.53 133.43 133.58 134.08 133.74 133.82 133.82 133.78 134.10 134.21 134.39 133.65 133.95 132.75 133.13 132.97 133.43 133.01 133.33 133.17 133.36 133.44 133.50 133.54 133.62 133.00 133.40 132.58 133.42 132.92 MEAN 133.30 133.20 133.11 133.60 134.14 131.43 129.59 133.98 133.74 133.29 133.30 133.09 MAX 133.62 133.68 133.58 134.19 134.42 133.51 133.43 134.45 134.39 134.08 133.63 133.72 MIN 133.00 132.68 132.58 132.73 133.57 129.09 127.16 133.33 132.96 132.57 132.76 132.48 292 RIO GRANDB DB LOIZA BASIN 50059000 LAGO LOIZA AT DAMSITB, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°19'49", long 66°01'00", at pumphouse at damsite, jillo Alto plaza. and 1.9 ml (3.1 km) south of Tru- DRAINAOE AREA.--208 sq mi (539 sq km). PERIOD OF RECORD.--Water years 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 06... DEC 04... FBB 1993 09... APR 08.. . HAY 24.. . AUG 06... DATE OCT 1992 06... DEC 04.. . FBB 1993 09... APR 08... HAY 24... AUG 06... DATE OCT 1992 06... DEC 04... FBB 1993 09.. . APR 08.. . HAY 24.. . AUG Off... TIME 1120 1215 1040 1250 1445 1130 ALKA- LINITY WAT WH TOT FBT FIELD MG/L AS CACO3 49 43 170 120 120 74 * «*>' NITRO- GEN, TOTAL (MG/L AS N03) 10 7.5 4.0 5.3 3.2 6.2 SPE- CIFIC CON- DUCT- ANCE (US/CM) 180 147 314 300 251 214 SULFIDB TOTAL (MG/L AS S) <0.5 -- -- <0.5 -- -- PHOS- PHORUS TOTAL (MG/L AS P) 0.210 0.170 0.220 0.200 0.190 0.20 PH WATER WHOLE FIELD (STAND- ARD UNITS) 6.8 7.2 8.3 6.8 6.6 6.9 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 12 <1 <1 21 42 4 BORON, TOTAL RECOV- ERABLE (UG/L AS B) 90 -- -- 60 -- -- TEMPER- ATURE WATER (DBG C) 30.0 25.9 26.2 29.1 28.5 28.6 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 1.35 0.560 0.570 0.150 0.070 0.090 COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) 80 -- -- <10 -- -- OXYGEN, DIS- SOLVED (MG/L) 2.5 2.0 1.7 1.6 1.5 2.5 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.050 0.040 0.030 0.050 0.030 0.010 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) 1200 -- -- 100 -- -- OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 33 26 22 21 19 32 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 1.40 0.600 0.600 0.200 0.100 0.100 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) 260 _- __ 340 -_ -- OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 17 <10 <10 <10 35 14 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.190 0.170 0.160 0.180 0.510 0.120 ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) 100 -- -- 40 -- -- COLI- FORM, FECAL, 0.45 UM-MP (COLS./ 100 ML) 56 580 K700 42 K820 120 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.71 0.43 0.94 0.52 0.99 1.2 CYANIDE TOTAL (MG/L AS CN) <0.010 -- _- <0.010 _- -- STREP- TOCOCCI FECAL, (COLS. PER 100 ML) K10 410 K20 32 570 K4 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.90 0.60 1.1 0.70 1.5 1.3 PHENOLS TOTAL (UG/L) 3 -- -_ 2 -- -- NITRO- GEN, TOTAL (MG/L AS N) 2.3 5.3 1.7 0.90 -- 1.4 MBTHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 0.07 -- -- 0.05 -- — K = non-ideal count RIO GRANDB DB LOIZA BASIN 50059050 RIO GRANDB DB LOIZA BELOW DAMSITB, PR LOCATION.--Lat 18«20'33" , long 66°00'20", Hydrologic Unit 21010005, on left bank of Highway 175, 1.1 mi (1.8 km) downstream of Lago Lolza Dam. 293 DRAINAGE AREA.--209 ml* (541 km*). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—December 1986 to current year. QAGE.--Water-stage recorder and crest-stage gage. Elevation of gage is 32 ft (10 m), from topographic map. REMARKS.--Record* poor. Flow regulated by Lago Loiza Dam. 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 HAR APR MAY JUN JUL ADO SEP 1 12 20 2 287 23 3 337 21 4 15 19 5 16 19 6 15 18 7 15 1070 8 16 5350 9 16 1570 10 16 694 11 16 108 12 16 187 13 196 64 14 8.2 140 15 7.9 4.9 16 7.9 4.9 17 7.8 231 18 7.7 5.0 19 7.8 4.9 20 7.8 5.1 21 8.0 400 22 7.8 318 23 7.9 5.6 24 8.0 210 25 8.0 220 26 8.0 11 27 8.0 298 28 8.0 223 29 8.0 217 30 263 11 31 23 —— TOTAL 1385.8 11472.4 MEAN 44.7 382 MAX 337 5350 MIN 7.7 4.9 AC-FT 2750 22760 CFSM .21 1.83 IN. .25 2.04 10 739 6.2 5.7 5.2 215 6.8 6.6 6.9 7.2 7.5 7.3 7.0 6.8 185 7.9 7.5 7.5 7.5 7.8 155 8.6 8.2 8.2 8.3 8.5 8.5 8.2 8.2 8.2 8.2 1498.5 48.3 739 5.2 2970 .23 .27 STATISTICS OF MONTHLY MEAN DATA MEAN 352 785 MAX 842 2732 (WY) 1991 1988 MIN 44.7 88.6 (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 ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 608 2603 1988 30.0 1990 FOR 8.2 8.2 8.3 8.9 12800 7210 479 415 170 637 142 22 19 269 8.9 125 5.7 187 6.5 6.7 6.8 7.0 7.3 7.8 94 12 12 12 13 13 14 22735.3 733 12800 5.7 45100 3.51 4.05 14 14 14 15 16 17 154 13 12 11 11 10 9.7 9.3 9.3 9.3 9.3 9.1 9.2 11 9.3 9.3 9.3 9.3 9.3 9.2 8.9 9.1 8.9 _-_ --- 459.8 15.9 154 8.9 912 .08 .08 FOR WATER YEARS 1987 211 733 1992 5.05 1990 103 242 1989 4.52 1990 9.3 9.3 9.5 9.7 9.7 9.6 9.4 9.5 9.3 9.3 9.3 8.9 8.9 9.3 9.3 9.3 10 11 10 9.9 8.9 8.9 8.9 8.9 8.9 8.9 8.9 9.1 9.5 8.8 8.5 288.7 9.31 11 8.5 573 .04 .05 - 1992 73.5 299 1989 6.45 1990 1991 CALENDAR YEAR 29801 81 5350 3 4 59110 5 195 8 5 .9 .6 Nov 8 .4 Sep 24 .9 Aug 12 .39 .30 .9 .6 8.4 8.1 8.0 7.5 7.4 7.2 8.3 8.2 7.4 6.2 5.5 4.7 4.5 3.7 3.8 4.4 4.4 4.7 11 7.4 4.7 4.4 4.1 4.0 3.7 3.7 3.3 3.1 4.1 8.5 --- 174.4 5.81 11 3.1 346 .03 .03 5.5 13 4.2 3.5 3.2 8.8 5.8 3.6 3.8 5.1 3.6 3.6 3.4 3.5 3.4 8.1 5.3 17 222 11 10 10 2010 3400 864 3550 478 233 29 241 208 11370.4 367 3550 3.2 22550 1.75 2.02 249 725 475 628 14 232 469 27 827 358 400 909 788 410 295 237 485 22 21 240 1100 21 15 302 10 10 10 10 10 10 9309 310 1100 10 18460 1.48 1.66 11 11 12 12 129 12 11 11 165 13 12 12 12 12 12 12 200 14 12 12 184 441 10 12 10 9.3 10 393 9.8 9.1 15 1800.2 58.1 441 9.1 3570 .28 .32 10 9.8 9.6 9.7 1880 220 366 9.4 288 11 452 7.7 8.0 11 468 10 10 11 11 12 11 12 12 12 11 12 12 12 12 11 12 3943.2 127 1880 7.7 7820 .61 .70 11 12 11 11 11 393 11 343 11 9.7 9.7 9.7 9.7 9.7 10 10 500 9.5 551 3380 2190 283 272 11 155 8.6 8.2 184 10 10 8454.8 282 3380 8.2 16770 1.35 1.50 , BY WATER YEAR (WY) 50.2 112 1987 5.81 1992 FOR 1992 72892. 199 12800 3. 3. 76300 33. 144600 12. 393 10 5. 125 367 1992 7.62 1990 WATER YEAR 5 Jan 5 1 Apr 28 7 Apr 23 Jan 5 32 Jan 5 95 97 6 222 784 1987 7.72 1991 133 339 1988 57.9 1990 WATER 274 652 44 51200 2 199 718 1988 27.4 1991 YEARS 1987 .5 Nov .1 Sep 2.2 Sep 124000 39 198900 1 17 449 12 5 Nov .57 Nov .31 .84 .1 442 1612 1989 29.7 1990 - 1992 1988 1990 27 1987 22 1990 18 1990 27 1987 27 1987 294 RIO GRANDB DB LOIZA BASIN 50059050 RIO GRANDB DB LOIZA BELOW DAHSITB, PR—Continued DISCHARGE, CUBIC FEET PBR SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JDL AUG SEP 1 103 122 2 10 6.9 3 9.0 9.2 4 9.5 348 5 9.9 214 6 277 207 7 275 129 8 235 8.3 9 11 7.5 10 286 151 11 13 162 12 8.1 7.4 13 8.2 7.3 14 8.2 7.5 15 8.2 212 16 9.3 8.4 17 9.2 177 18 8.9 1070 19 89 114 20 9.5 187 21 8.9 259 22 139 184 23 8.0 7.4 24 8.4 243 25 8.3 6.3 26 175 6.1 27 6.0 694 28 5.7 3020 29 5.7 376 30 15 3430 31 16 —— TOTAL 1793.0 11381.3 MEAN 57.8 379 MAX 286 3430 MIN 5.7 6.1 AC-FT 3560 22570 CFSM .28 1.82 IN. .32 2.03 298 388 9.6 245 142 12 180 9.9 9.4 9.3 9.2 8.9 11 200 271 10 10 151 11 9.7 9.7 12 178 13 12 1920 245 195 201 815 410 6005.7 194 1920 8.9 11910 .93 1.07 STATISTICS OF MONTHLY MEAN DATA MEAN 303 717 MAX 842 2732 (WY) 1991 1988 MIN 44.7 88.6 (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 ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 539 2603 1988 30.0 1990 FOR 360 334 5.3 263 5.0 4.6 234 293 4.9 188 5.6 5.7 5.7 5.7 5.8 5.9 153 5.4 5.6 5.8 6.1 265 9.0 8.0 9.6 8.8 227 9.5 430 8.1 7.8 2884.9 93.1 430 4.6 5720 .45 .51 8.2 193 12 10 10 10 9.6 9.2 8.4 8.1 8.0 8.8 9.8 8.2 8.2 8.2 8.4 8.2 8.0 7.7 7.6 7.7 7.5 7.5 7.5 7.6 7.8 7.9 ___ ___ --- 423.1 15.1 193 7.5 839 .07 .08 FOR WATER YEARS 1987 195 733 1992 5.05 1990 90.3 242 1989 4.52 1990 7.7 7.5 8.1 8.2 8.3 7.8 7.7 7.5 7.6 7.1 7.3 7.2 7.0 6.8 7.0 7.8 7.5 6.7 6.5 6.2 6.1 6.2 6.0 11 7.3 6.0 5.7 5.6 5.5 5.3 5.4 217.6 7.02 11 5.3 432 .03 .04 - 1993 64.0 299 1989 6.45 1990 1992 CALENDAR YEAR 77715.8 212 12800 3.1 3.7 154100 1.02 13.83 395 11 6.2 Jan 5 Apr 28 Apr 23 5.4 5.4 5.1 5.3 5.2 5.1 4.8 5.9 5.4 4.8 4.8 6.4 15 6.8 6.3 6.2 6.0 6.3 6.2 7.4 8.8 5.4 4.1 3.7 3.6 3.8 4.2 3.6 6.4 5.1 172.5 5.75 15 3.6 342 .03 .03 , BY WATER 43.9 112 1987 5.75 1993 810 1090 7.1 7.1 127 120 9.2 8.9 287 243 15 14 14 1470 201 12 12 12 142 14 14 14 15 17 15 401 18 272 11 10 10 5412.3 175 1470 7.1 10740 .84 .96 YEAR (WY) 132 367 1992 7.62 1990 9.1 8.7 8.5 8.2 8.7 8.3 8.5 8.7 8.6 8.3 8.1 8.2 8.1 363 261 7.8 6.5 6.2 4200 1870 274 388 7.7 213 5.2 4.5 4.0 3.7 224 4.3 --- 7952.9 265 4200 3.7 15770 1.27 1.42 228 784 1987 7.72 1991 FOR 1993 WATER YEAR 64166.0 176 11600 3.6 4.1 45100 27.69 127300 .84 11.42 335 8.8 5.4 Jul 11 Apr 25 Apr 22 Jul 11 Jul 11 3.9 178 155 6.7 3.9 3.9 264 138 51 101 11600 600 600 205 170 411 167 10 173 9.5 9.6 1410 2130 1120 215 520 192 182 10 180 9.5 20829.0 672 11600 3.9 41310 3.21 3.71 210 672 1993 57.9 1990 WATER 258 652 44. 51200 2. 2. 124000 39. 186900 1. 16. 427 11 5. 9.1 198 8.5 7.8 7.8 179 7.7 7.1 7.3 7.4 7.1 6.5 6.5 217 6.9 935 252 5.7 5.4 4.9 5.1 330 341 5.3 217 5.4 5.2 5.5 9.2 6.7 5.7 2822.8 91.1 935 4.9 5600 .44 .50 184 718 1988 27.4 1991 YEARS 1987 5 Nov 1 Sep 2 Sep Nov 57 Nov 23 78 2 5.6 353 5.9 5.7 7.4 303 7.0 5.8 237 6.8 406 7.5 7.3 7.4 7.5 8.6 253 611 6.9 203 5.6 5.6 490 11 337 6.1 6.2 294 6.0 654 4270.9 142 654 5.6 8470 .68 .76 399 1612 1989 29.7 1990 - 1993 1988 1990 27 1987 22 1990 18 1990 27 1987 27 1987 RIO GRANDS DB LOIZA BASIN 50059050 RIO GRANDS DB LOIZA BELOW DAMS ITS, PR—Continued WATER-QUALITY RECORDS PERIOD OF RECORD.-- Water years 1987 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE! December 1986 to September 1993. INSTRUMENTATION.—- Automatic sediment sampler. EXTREMES FOR PERIOD OF DAILY RECORD.— SEDIMENT CONCENTRATIONt Maximum daily mean, 946 mg/L Jan. 06, 1993; Minimum daily mean, 1 mg/L several days. SEDIMENT LOADS: Maximum daily mean, 98,600 tons (89,400 tonnes) Jan. 05, 1993; Minimum daily mean, 0.03 ton (0.02 tonnes) several days. EXTREMES FOR WATER YEARS 1992-93.-- SEDIMENT CONCENTRATION: Maximun daily mean, 274 mg/1 October 21, 1990; minimun daily mean, 1 mg/1 several days. SEDIMENTS LOADS: Maximun daily mean, 4,920 tons (4,480 tonnes) October 21, 1990: minimum daily mean, 0.03 tons (0.02 tonnes) several days. 295 Water Suspended- sediment concentration (mg/L) Year 1992 1993 maximum 946 (Jan. 831 (July 06) 5 11) 5 minimum (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 (CFS) 11 8.9 337 15 16 15 15 16 16 16 16 16 196 8.2 7.9 7.9 7.8 7.7 7.8 7.8 8.0 7.8 7.9 8.0 8.0 8.0 8.0 8.0 8.0 263 23 MEAN CONCEN- TRATION (MG/L) OCTOBER 23 41 31 26 26 26 25 25 23 21 20 20 34 14 10 10 10 10 10 10 10 10 10 10 10 10 10 10 10 28 29 SEDIMENT DISCHARGE (TONS/DAY) .76 512 90 1.1 1.1 1.1 1.1 1.1 .98 .88 .85 .86 481 .31 .22 .22 .22 .21 .22 .22 .22 .22 .22 .23 .23 .23 .22 .22 .23 509 2.0 MEAN DISCHARGE (CFS) 20 23 21 19 19 18 1070 5350 1570 694 108 187 64 140 4.9 4.9 231 5.0 4.9 5.1 400 318 5.6 210 220 11 298 223 217 11 Suspended- sediment ma 98,600 55,100 tximum (Jan. 05) (July 11) discharge (tons per day) minimum .05 (Several days) .07 (Several days) , HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN CONCEN- TRATION (MG/L) NOVEMBER 27 27 25 25 25 25 84 304 82 52 27 33 19 26 17 16 85 88 86 83 96 153 52 54 40 24 39 36 36 24 ___ SEDIMENT DISCHARGE (TONS /DAY) 1.4 1.7 1.4 1.3 1.3 1.2 919 8270 1050 261 44 93 18 37 .22 .21 91 1.2 1.2 1.1 228 125 .98 89 87 .79 135 77 71 .82 MEAN DISCHARGE (CFS) 10 739 6.2 5.7 5.2 215 6.8 6.6 6.9 7.2 7.5 7.3 7.0 6.8 185 7.9 7.5 7.5 7.5 7.8 155 8.6 8.2 8.2 8.3 8.5 8.5 8.2 8.2 8.2 8.2 MEAN CONCEN- TRATION (MG/L) DECEMBER 22 53 17 17 17 31 19 18 18 18 18 18 18 18 37 24 22 20 20 20 30 21 20 17 13 11 11 10 9 9 8 SEDIMENT DISCHARGE (TONS/ DAY) .63 761 .29 .26 .24 84 .34 .33 .34 .35 .37 .35 .34 .34 85 .49 .43 .40 .40 .43 47 .48 .43 .38 .30 .26 .24 .21 .20 .20 .19 TOTAL 1106.7 1607.47 11472.4 11609.82 1498.5 986.22 296 RIO QRANDB DB LOIZA BASIN 50059050 RIO QRANDB DB LOIZA BELOW DAMSITB LOIZA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAY MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MQ/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 8.2 8.2 8.3 8.9 12800 7210 479 415 170 637 142 22 19 269 8.9 125 5.7 187 6.5 6.7 6.8 7.0 7.3 7.8 94 12 12 12 13 13 14 6 5 4 4 753 946 363 264 248 139 126 99 97 100 88 85 73 69 54 44 34 26 22 21 20 20 20 19 18 16 16 .15 .12 .10 .10 98600 30800 475 300 124 722 60 6.3 5.1 192 2.1 44 1.2 58 .97 .79 .61 .48 .42 .43 5.6 .62 .63 .61 .62 .58 .58 MEAN MEAN MEAN CONCBN- SEDIMENT MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE (CFS) (HG/L) (TONS /DAY) (CFS) (MQ/L) (TONS/DAY) FEBRUARY 14 14 14 15 16 17 154 13 12 11 11 10 9.7 9.3 9.3 9.3 9.3 9.1 9.2 11 9.3 9.3 9.3 9.3 9.3 9.2 8.9 9.1 8.9 ___ ___ 16 16 16 15 13 10 8 8 8 8 8 7 6 6 6 6 6 5 5 6 6 26 6 6 6 6 6 5 6 .58 .59 .60 .59 .54 .46 3.6 .27 .26 .25 .23 .21 .17 .16 .16 .16 .16 .14 .12 .19 .16 .64 .16 .16 .16 .15 .14 .14 .14 ___ MARCH 9.3 9.3 9.5 9.7 9.7 9.6 9.4 9.5 9.3 9.3 9.3 8.9 8.9 9.3 9.3 9.3 10 11 10 9.9 8.9 8.9 8.9 8.9 8.9 8.9 8.9 9.1 9.5 8.8 8.5 5 5 5 6 7 8 10 10 10 10 10 9 8 8 8 9 9 9 8 8 8 8 8 8 8 8 7 7 7 6 6 .13 .12 .13 .16 .18 .21 .24 .26 .26 .26 .25 .22 .20 .20 .20 .22 .27 .27 .24 .21 .20 .20 .20 .20 .20 .20 .18 .18 .18 .15 .14 TOTAL 22735.3 —— 131403.11 459.8 11.29 288.7 6.26 RIO GRANDE DB LOIZA BASIN 50059050 RIO GRANDB DB LOIZA BELOW DAMSITB LOIZA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 297 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 8.4 8.1 8.0 7.5 7.4 7.2 8.3 8.2 7.4 6.2 5.5 4.7 4.5 3.7 3.8 4.4 4.4 4.7 11 7.4 4.7 4.4 4.1 4.0 3.7 3.7 3.3 3.1 4.1 8.5 APRIL 7 8 10 12 10 7 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 6 7 7 7 7 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) MAY .15 .18 .20 .24 .20 .14 .11 .12 .10 .08 .07 .06 .06 .05 .06 .06 .06 .06 .16 .11 .06 .06 .06 .06 .05 .07 .06 .06 .08 .15 5.5 13 4.2 3.5 3.2 8.8 5.8 3.6 3.8 5.1 3.6 3.6 3.4 3.5 3.4 8.1 5.3 17 222 11 10 10 2010 3400 864 3550 478 233 29 241 208 8 9 9 10 10 9 9 9 9 10 10 10 10 10 10 10 10 10 42 97 96 92 157 365 354 270 178 42 29 38 43 .13 .31 .10 .08 .09 .20 .15 .08 .09 .14 .10 .09 .10 .09 .10 .21 .15 .45 91 3.0 2.7 2.5 1530 3230 1040 3550 217 104 2.5 77 80 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) JUNE 249 725 475 628 14 232 469 27 827 358 400 909 788 410 295 237 485 22 21 240 1100 21 15 302 10 10 10 10 10 10 57 58 45 51 25 42 46 28 81 43 39 71 87 47 41 38 49 25 19 17 65 10 10 34 27 23 19 16 13 11 140 1200 517 741 1.0 114 456 2.4 988 375 433 1240 587 513 458 222 683 1.6 1.1 11 1360 .58 .41 134 .75 .61 .50 .44 .36 .28 TOTAL 174.4 2.98 11370.4 9932.36 9309 10182.03 298 RIO GRANDS DB LOIZA BASIN 50059050 RIO GRANDS DB LOIZA BELOW DAHSITB LOIZA, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 MEAN MEAN CONCBN- 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 11 11 12 12 129 12 11 11 165 13 12 12 12 12 12 12 200 14 12 12 184 441 10 12 10 9.3 10 393 9.8 9.1 15 1800.2 72613.4 JULY 10 10 10 10 10 10 10 10 26 10 10 10 10 10 10 10 25 10 8 7 21 11 10 10 10 10 10 25 18 17 14 —— SEDIMENT DISCHARGE (TONS/DAY) MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AUGUST .29 .30 .30 .31 3.4 .31 .30 .32 51 .34 .32 .32 .33 .33 .32 .32 63 .38 .26 .22 53 23 .31 .38 .27 .26 .28 138 .47 .41 .55 339.60 176333.37 10 9.8 9.6 9.7 1880 220 366 9.4 288 11 452 7.7 8.0 11 468 10 10 11 11 12 11 12 12 12 11 12 12 12 12 11 12 3943.2 11 10 10 10 21 6 28 11 108 275 147 69 50 41 44 34 27 21 19 16 12 10 10 10 10 9 9 8 8 7 7 —— .29 .27 .26 .27 252 3.8 360 .25 204 8.5 163 1.4 1.0 1.3 136 .95 .74 .62 .58 .48 .35 .32 .32 .32 .29 .28 .29 .26 .24 .22 .21 1138.81 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) SEPTEMBER 11 12 11 11 11 393 11 343 11 9.7 9.7 9.7 9.7 9.7 10 10 500 9.5 551 3380 2190 283 272 11 155 8.6 8.2 184 10 10 8454.8 6 6 6 6 6 10 11 27 9 10 10 10 10 10 10 10 6 2 36 159 125 40 100 106 85 70 54 66 64 53 —— .20 .19 .18 .18 .19 45 .32 324 .27 .25 .26 .26 .26 .26 .27 .28 14 .05 528 5760 1750 245 276 3.0 73 1.6 1.2 86 1.8 1.4 9113.42 RIO GRANDE DE LOIZA BASIN 50059050 RIO GRANDE DE LOIZA BELOW DAMSITE LOIZA, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 299 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 (CFS) (MG/L) (TONS/DAY) OCTOBER 103 10 9. 9. 9. 277 275 235 11 286 13 8. 8. 8. 8. 9. 9. 8. 89 9. 8. 139 8. 8. 8. 175 6. 5. 5. 15 16 0 5 9 1 2 2 2 3 2 9 5 9 0 4 3 0 7 7 27 22 20 21 21 40 35 33 22 37 18 16 16 16 16 16 16 16 29 43 38 30 16 16 16 21 12 11 10 17 20 31 .57 .49 .56 .55 144 83 81 .64 80 1.0 .35 .36 .36 .36 .44 .39 .38 23 1.1 .90 52 .36 .39 .34 62 .19 .17 .16 1.3 1.4 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) NOVEMBER 122 6. 9. 348 214 207 129 8. 7. 151 162 7. 7. 7. 212 8. 177 1070 114 187 259 184 7. 243 6. 6. 694 3020 376 3430 -- 9 2 3 5 4 3 5 4 4 3 1 - 26 13 12 42 26 21 27 16 14 25 24 15 15 15 27 18 28 58 49 31 27 28 18 25 15 15 54 105 31 336 32 247 107 93 34 37 62 57 50 498 22 53 121 44 113 179 1880 202 3980 .28 .46 .41 .27 .29 .29 .30 .42 .37 .25 .25 ___ MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) DECEMBER 298 388 9.6 245 142 12 180 9.9 9.4 9.3 9.2 8.9 11 200 271 10 10 151 11 9.7 9.7 12 178 13 12 1920 245 195 201 815 410 281 268 58 87 20 22 31 20 20 20 20 20 20 30 64 20 20 27 21 20 20 20 25 22 20 76 33 25 28 61 36 367 372 1.8 167 32 .83 46 .56 .52 .50 .49 .48 .62 86 115 .54 .54 32 .59 .52 .52 .68 35 .75 .68 1050 65 85 96 207 134 TOTAL 1793.0 568.76 11381.3 7814.59 6005.7 2899.62 300 RIO GRAKDB DE LOIZA BASIN 50059050 RIO GRANDB DB LOIZA BELOW DAMSITB LOIZA, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (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 31 360 334 5.3 263 5.0 4.6 234 293 4.9 188 5.6 5.7 5.7 5.7 5.8 5.9 153 5.4 5.6 5.8 6.1 265 9.0 8.0 9.6 8.8 227 9.5 430 8.1 7.8 34 29 15 23 16 12 27 34 17 24 10 10 10 10 10 10 21 11 11 11 11 22 19 16 15 15 26 20 33 20 19 133 188 .22 121 .20 .15 50 73 .21 69 .15 .16 .16 .16 .16 .16 52 .16 .16 .17 .18 126 .47 .34 .42 .35 70 .54 248 .43 .40 8.2 193 12 10 10 10 9.6 9.2 8.4 8.1 8.0 8.8 9.8 8.2 8.2 8.2 8.4 8.2 8.0 7.7 7.6 7.7 7.5 7.5 7.5 7.6 7.8 7.9 FEBRUARY 17 27 23 21 20 20 25 35 39 39 36 34 31 26 21 20 18 15 11 10 9 6 5 5 5 6 6 6 49 .38 I .84 .58 .54 .53 .64 .83 .88 .81 .74 .77 .83 .56 .46 .44 .41 .32 .23 .21 .19 .13 .10 .10 .11 .12 .12 .12 MEAN DISCHARGE (CFS) 7.7 7.5 8.1 8.2 8.3 7.8 7.7 7.5 7.6 7.1 7.3 7.2 7.0 6.8 7.0 7.8 7.5 6.7 6.5 6.2 6.1 6.2 6.0 11 7.3 6.0 5.7 5.6 5.5 5.3 5.4 MEAN CONCEN- TRATION (MG/L) MARCH 6 6 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 7 6 6 6 6 6 12 20 20 20 20 20 20 33 SEDIMENT DISCHARGE (TONS/DAY) .13 .13 .16 .15 .15 .14 .14 .14 .14 .14 .14 .14 .13 .12 .12 .14 .14 .12 .11 .10 .10 .10 .09 .64 .41 .32 .30 .30 .29 .29 .50 TOTAL 2884.9 1135.35 423.1 60.99 217.6 6.02 RIO GRANDE DB LOIZA BASIN 50059050 RIO GRANDB DB LOIZA BELOW DAHSITB LOIZA, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 30 i 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 5.4 5.4 5.1 5.3 5.2 5.1 4.8 5.9 5.4 4.8 4.8 6.4 15 6.8 6.3 6.2 6.0 6.3 6.2 7.4 8.8 5.4 4.1 3.7 3.6 3.8 4.2 3.6 6.4 5.1 --- APRIL 32 30 27 25 23 19 13 10 10 10 10 10 18 18 14 12 12 12 11 10 14 15 10 10 8 8 8 8 12 14 --- MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) HAY .48 .45 .37 .34 .32 .26 .18 .16 .15 .13 .13 .18 1.3 .33 .25 .21 .20 .21 .18 .20 .46 .25 .11 .10 .08 .07 .07 .08 .27 .20 810 1090 7.1 7.1 127 120 9.2 8.9 287 243 15 14 14 1470 201 12 12 12 142 14 14 14 15 17 15 401 18 272 11 10 10 52 63 17 15 25 24 21 20 33 42 24 24 24 47 43 23 23 23 31 24 24 24 21 23 25 36 23 26 20 20 20 511 275 .33 .29 41 25 .53 .48 58 54 1.0 .88 .88 339 50 .74 .74 .74 37 .88 .88 .88 .92 1.2 1.0 191 1.1 57 .61 .56 .52 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) JUNE 9.1 8.7 8.5 8.2 8.7 8.3 8.5 8.7 8.6 8.3 8.1 8.2 8.1 363 261 7.8 6.5 6.2 4200 1870 274 388 7.7 213 5.2 4.5 4.0 3.7 224 4.3 ___ 20 18 17 17 16 16 16 16 15 15 15 15 14 20 23 7 5 5 88 210 42 38 19 25 16 13 10 8 20 14 ___ .48 .43 .40 .38 .38 .36 .37 .38 .36 .34 .34 .32 .30 95 44 .18 .08 .08 1100 1350 67 111 .47 47 .24 .15 .11 .08 60 .18 TOTAL 172.5 7.72 5412.3 1653.16 7952.9 2880.41 302 RIO GRANDE DE LOIZA BASIN 50059050 RIO GRANDE DE LOIZA BELOW DAMSITE LOIZA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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 3.9 178 155 6.7 3.9 3.9 264 138 51 101 11600 600 600 205 170 411 167 10 173 9.5 9.6 1410 2130 1120 215 520 192 182 10 180 9.5 20829.0 64166.0 JULY 10 23 20 19 14 10 28 20 21 21 831 52 43 32 29 43 30 21 31 20 20 59 93 73 36 37 33 44 50 38 21 —— MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AUGUST .10 50 43 .47 .15 .10 68 43 12 25 55100 147 292 64 50 116 45 .61 42 .52 .53 711 711 318 56 304 47 47 1.4 45 .53 58340.41 78464.25 9.1 198 8.5 7.8 7.8 179 7.7 7.1 7.3 7.4 7.1 6.5 6.5 217 6.9 935 252 5.7 5.4 4.9 5.1 330 341 5.3 217 5.4 5.2 5.5 9.2 6.7 5.7 2822.8 18 29 20 18 17 28 19 17 15 15 14 14 13 26 19 56 25 10 10 10 10 26 31 10 26 13 10 10 14 14 12 —— .43 56 .45 .37 .36 51 .38 .31 .29 .28 .26 .24 .22 68 .37 289 112 .15 .14 .13 .14 135 181 .14 58 .19 .14 .15 .51 .25 .18 956.08 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) SEPTEMBER 5.6 353 5.9 5.7 7.4 303 7.0 5.8 237 6.8 406 7.5 7.3 7.4 7.5 8.6 253 611 6.9 203 5.6 5.6 490 11 337 6.1 6.2 294 6.0 654 4270.9 10 24 13 10 10 24 18 13 22 18 29 13 10 10 10 10 25 34 19 24 15 14 27 18 25 15 15 25 16 37 189 .16 I .20 .15 .20 136 .36 .20 103 .31 233 .24 .19 .20 .20 .24 127 338 .37 94 .22 .22 271 .89 181 .25 .25 126 .29 338 2141.14 RIO GRANDB DB LOIZA BASIN 50059050 RIO GRANDB DB LOIZA BELOW DAMSITB, PR—Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1993 PARTICLE-SIZE DISTRIBUTION OP SUSPENDED SEDIMENT 303 MAY 1! 2: 2! 2 MAY o: JUL DATE JAN 1992 05... 05... MAY 19... 23... 25... 26. .. MAY 1993 01... JUL 11... ITB 1992 ». . . 1. . . 1993 TIME 1805 1935 1803 1526 0148 1623 1500 1821 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .016 MM -- 79 58 51 63 56 64 64 DIS- CHARGE, INST. CUBIC FEET PER SECOND 16400 39400 4110 4115 4290 6240 3770 24200 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM 81 81 71 52 73 64 77 74 SEDI- MENT, SUS- PENDED (MG/L) 1730 1710 2790 678 748 4510 3170 7360 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 97 98 85 79 91 85 90 93 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 76600 182000 31000 7530 8660 76000 32500 481000 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 99 99 94 89 96 95 97 99 SBD. SUSP. PALL DIAM. PERCENT FINER THAN .002 MM 63 65 30 38 50 35 35 39 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 99 99 97 93 98 99 98 99.8 SBD. SUSP. PALL DIAM. PERCENT FINER THAN .004 MM 70 70 38 -- 59 43 40 43 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 100 100 99 95 99 99 99 99.9 SED. SUSP. PALL DIAM. PERCENT FINER THAN .008 MM 75 73 44 50 -- 50 51 51 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 100 100 100 97 100 100 99.6 100 304 RIO GRANDE DE LOZZA BASIN 50059050 RIO GRANDE DE LOZZA BLW DAMSITE, PR--Continued WATER QOALITY DATA, WATER YEAR OCTOBER 1991 TO SEPTEMBER 1993 SILT AND CLAY PERCENT OF SOSFENDED SEDIMENT DATE NOV 1991 20... 21... 22... JAN 1992 05... 05. .. 05... 07... 08... MAY 23... 23... 25... 26... JUL 28... SEP 23... OCT 06. .. APR 1993 14... 23... MAY 01... 02... JUL 11. .. 12... TIME 1120 2014 2217 1750 1915 2155 1155 1233 1531 2234 2150 0335 1045 1520 1649 1430 1055 1515 1913 1536 1330 STREAM- FLOW, INSTAN- TANEOUS (CFS) 5.1 7950 13400 14050 34500 74760 2860 166 4115 3650 4110 30600 4950 33 1860 6.8 4.2 9520 12000 35900 197 SEDI- MENT, SUS- PENDED (MG/L) 83 193 125 2280 1680 1970 365 264 513 360 593 427 489 175 1390 326 111 361 105 680 413 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 1.14 4140 4520 86500 156000 398000 2820 118 5700 3550 4110 35300 6530 16 6980 6.0 1.3 9280 3410 65900 220 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 98 90 85 98 99 99 99 99 83 72 94 99 91 99 93 95 97 75 87 82 99 305 RIO GRANDE DE LOIZA 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 Lofxa Reservoir. DRAINAGE AREA.--213 mi" (552 km1 ). PERIOD OP RECORD.—Water years 1981 to current year. REMARKS.--Flow controlled by Lago Loiza reservoir. WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 4 mi (0.6 km) DATE OCT 1992 06... DEC 07... FEE 1993 09... APR 08. .. MAY 24... AUG 06... TIME 0945 1100 0950 1115 1330 1030 DIS- CHARGE, INST. CUBIC FEET PER SECOND 16 18 15 15 31 87 SPE- CIFIC CON- DUCT- ANCE (US /CM) 258 300 430 440 207 205 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.8 7.7 7.1 7.9 7.2 6.9 TEMPER- ATURE WATER (DBG C) 29.0 25.2 25.6 32.0 27.9 29.3 TUR- BID- ITY (NTU) 28 12 27 2.3 160 240 OXYGEN, DIS- SOLVED (MG/L) 9.3 6.2 10.8 12.2 6.4 5.5 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 120 74 131 160 81 71 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 10 10 15 11 74 <10 COLI- FORM, FECAL, 0.45 DM-MF (COLS./ 100 ML) K500 5500 2800 280 K130000 K16000 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) K130 480 170 K10 K120000 570 DATE OCT 1992 06... DEC 07... FBB 1993 09... APR 08. .. MAY 24... AUG 06... HARD- NESS TOTAL (MG/L AS HARD- NESS NONCARB WH WAT TOT PLD 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 SULPIDE TOTAL (MG/L SULPATE DIS- SOLVED (MG/L CHLO- RIDE, DIS- SOLVED (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) AS K) 52 3 29 6.1 13 0.7 2.5 140 0 34 14 34 1 2.6 120 5 15 11 25 1 2.9 CAC03 84 100 71 150 70 46 AS S) AS SO4) AS CL) 1.1 14 <0.5 19 24 18 33 29 SOLIDS, DATE OCT 1992 06.. . DEC 07... FEB 1993 09... APR 08... MAY 24... AUG 06... PLUO- RIDB, DIS- SOLVED (MG/L AS F) <0.10 -- -- 0.20 -- <0.10 SILICA, DIS- SOLVED (MG/L AS SI 02) 21 -- -- 26 — 35 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 130 -_ -- 253 -- 210 RESIDUE SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, SOLVED DEG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC (TONS SUS- 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) 12 25 33 6 368 18 0.870 0.970 0.480 0.270 — -- 0.020 0.030 0.020 0.030 <0.010 <0.010 0.890 1.00 0.500 0.300 0.100 0.200 0.030 0.030 0.060 0.070 0.030 0.030 0.47 0.27 0.44 0.73 0.27 0.57 non-ideal count 306 RIO QRANDE DB LOIZA BASIN 50059100 RIO QRANDE DB LOIZA BELOW TRUJILLO ALTO, PR--Continued WATER-QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 06... DEC 07... PEB 1993 09... APR 08... MAY 24.. . AOG 06... DATE OCT 1992 06... DEC 07... PEB 1993 09... APR 08... MAY 24... AOG 06... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.50 0.30 0.50 0.80 0.30 0.60 IRON, TOTAL RECOV- ERABLE (DG/L AS FB) 1300 -- -- 270 -- -- NITRO- GEN, TOTAL (MG/L AS N) 1.4 1.3 1.0 1.1 0.40 0.80 LEAD, TOTAL RECOV- ERABLE (DG/L AS PB) <1 -- -- <1 -- -- NITRO- GEN, TOTAL (MG/L AS N03) 6.2 5.8 4.4 4.9 1.8 3.5 MANGA- NESE, TOTAL RECOV- ERABLE (DG/L AS MN) 50 -- -- 100 -- -- PHOS- PHORUS ARSENIC TOTAL TOTAL (MG/L (OG/L AS P) AS AS) 0.230 <1 0.260 0.310 0.320 2 0.260 0.180 MERCURY TOTAL SBLB- RECOV- NIUM, BRABLB TOTAL (UG/L (UG/L AS HG) AS SB) <0.10 <1 _- __ <0.10 <1 __ __ BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 -- -- <100 -- - - SILVER, TOTAL RECOV- ERABLE (DG/L AS AG) <1 -- -- <1 -- -- BORON, TOTAL RECOV- ERABLE (UG/L AS B) 30 -- -- 60 -- - - ZINC, TOTAL RECOV- ERABLE (DG/L AS ZN) 20 -- -- 20 -- -- CHRO- CADMIUM MIDM, TOTAL TOTAL RECOV- RECOV- ERABLE BRABLB (UG/L (UG/L AS CD) AS CR) <1 2 __ __ <1 1 __ - - - - CYANIDE TOTAL PHENOLS (MG/L TOTAL AS CN) (UG/L) •cO.010 1 __ __ <0.010 <1 __ __ COPPER, TOTAL RECOV- ERABLE (UG/L AS CO) <10 -- -- <10 -- ~ - MBTHY- LBNB BLUB ACTIVE SUB- STANCE (MG/L) 0.05 -- -- 0.05 -- -- RIO GRANDE DE LOIZA BASIN 50061000 RIO GRANDE DE LOIZA AT CAROLINA, PR 307 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 AREA.--243 mi* (629 km»). WATER-STAGE RECORDS PERIOD OF RECORD.—January 1991 to current year. GAGE.--Water-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 PERIOD OF RECORD.--Maximum gage-height, 33.18 ft (10.113 m), Jan. 6, 1992; minimum, 3.91 ft (1.192 m), Aug. 6, 1991. EXTREMES FOR CURRENT YEAR.--Maximum gage-height, 27.31 ft (8.324 m), July 11; minimum 3.95 ft (1.204 m), June 5. GAGE HEIGHT, FEET, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAY DAILY MEAN VALUES OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AOG 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 5.90 5.43 5.44 5.53 5.26 5.78 6.24 6.29 5.33 6.01 5.82 5.02 4.95 5.01 5.10 5.17 5.20 5.88 5.75 5.16 5.03 6.08 5.45 5.46 5.39 5.97 5.19 5.20 5.19 5.92 5.95 5.52 6.29 4.95 6.18 5.61 5.53 7.91 6.67 6.04 6.24 5.76 5.31 5.98 5.92 5.45 5.61 5.51 6.03 5.41 5.46 7.84 6.66 6.53 6.42 6.74 5.77 6.14 5.14 5.00 6.04 10.98 6.90 10.11 --- 6.36 10.98 5.00 6.28 6.81 4.93 6.11 5.04 5.48 5.68 5.23 4.98 4.83 4.84 4.85 5.03 6.32 6.78 5.44 5.33 5.92 5.07 4.79 4.85 5.05 5.51 5.63 5.17 9.61 7.45 6.47 6.75 8.30 6.78 5.85 9.61 4.79 6.36 < 6.15 ! 4.96 ! 5.90 ! 5.14 ! 5.05 6.38 6.26 4.97 5.82 5.01 4.89 4.85 4.75 4.65 4.69 5.55 4.77 4.74 ! 4.74 ! 4.71 ! 5.81 ! 5.36 ' 4.95 i 4.97 - 4.82 5.33 5.34 6.79 5.00 4.75 5.27 6.79 4.65 ' 1.76 5.30 >.51 >.33 >.27 .97 .87 .80 .75 .63 .64 .77 .75 .79 .85 .96 .94 .99 5.01 5.09 5.50 >.27 1.95 1.87 1.91 5.07 5.04 5.03 ___ 1.99 5.51 1.63 5.06 5.47 5.85 6.06 6.23 6.38 6.51 6.63 6.67 6.20 5.78 5.63 5.53 5.44 5.50 5.79 6.19 6.43 6.62 6.73 6.82 6.91 6.81 5.96 5.56 5.04 4.97 4.96 5.00 5.09 5.12 5.90 6.91 4.96 5.18 5.31 5.44 5.55 5.69 5.81 5.90 6.05 6.37 6.54 6.67 7.11 6.36 5.45 5.12 5.16 5.05 4.97 4.95 5.01 5.32 5.38 5.16 5.08 5.14 5.26 5.35 5.45 5.85 6.55 5.61 7.11 4.95 6.68 .60 8.61 .58 5.78 .53 4.88 .50 5.59 .48 5.29 .47 5.22 .54 4.91 .62 5.79 .69 6.29 .71 5.02 .69 4.80 .68 4.95 .70 7.61 5.52 6.08 5.58 4.82 5.37 4.77 4.72 4.67 4.62 5.32 11.36 4.67 9.97 4.65 6.25 4.64 6.13 4.75 5.48 4.92 5.51 4.90 4.83 5.76 4.62 5.59 4.69 6.07 4.68 4.73 5.30 4.69 5.15 4.66 —— 5.39 5.32 8.61 11.36 4.64 4.47 4.71 5.62 4.83 5.48 4.77 4.79 5.96 5.04 5.64 5.44 14.75 8.96 6.57 6.47 5.43 6.90 5.69 5.29 5.85 4.99 5.00 6.93 10.77 8.60 6.54 6.24 6.24 5.68 5.09 5.83 4.97 6.29 14.75 4.71 4.92 5.88 5.01 4.97 4.99 5.70 5.04 5.00 5.02 5.00 4.98 5.01 5.00 5.70 5.28 7.45 6.33 5.21 5.13 5.10 5.19 6.13 6.13 5.21 5.85 5.08 5.10 5.15 5.20 5.20 5.14 5.36 7.45 4.92 5.08 6.11 5.21 5.14 5.19 6.09 5.54 5.06 5.76 5.11 6.05 5.32 5.29 5.33 5.33 5.36 6.47 6.44 5.97 6.08 5.40 5.25 5.59 6.21 6.15 5.28 5.16 5.77 5.64 6.47 --- 5.63 6.47 5.06 308 RIO GRANDS DB 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 Loiza. DRAINAGE AREA.--9.84 mi> (25.48 km'). 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 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JDL AUG SEP 1 18 6.2 2 16 5.7 3 11 20 4 8.4 96 5 7.6 30 6 9.4 14 7 11 13 8 9.3 9.8 9 9.4 9.9 10 9.7 e63 11 8.3 e!3 12 7.9 e!3 13 7.3 36 14 10 14 15 7.9 11 16 7.0 40 17 7.2 25 18 12 52 19 8.1 31 20 13 32 21 7.5 108 22 7.0 135 23 8.6 50 24 7.0 32 25 6.7 23 26 6.2 e21 27 7.7 e!59 28 8.0 el!3 29 6.2 e!03 30 6.2 e79 31 9.4 TOTAL 279.0 1357.6 MEAN 9.00 45.3 MAX 18 159 MIN 6.2 5.7 AC-FT 553 2690 CFSM .91 4.60 IN. 1.05 5.13 STATISTICS OF MONTHLY MEAN MEAN 44.1 46.4 MAX 273 125 (WY) 1971 1985 MIN 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 (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS e22 e!6 el4 49 26 32 23 19 17 16 14 13 12 16 26 15 14 14 15 13 12 36 20 28 32 186 49 47 120 199 46 1161 37.5 199 12 2300 3.81 4.39 DATA 34.6 116 1971 5.82 1968 FOR 43 32 29 27 29 35 59 39 29 24 23 23 21 22 20 19 18 17 17 17 16 20 30 18 31 21 20 e32 86 29 20 866 27.9 86 16 1720 2.84 3.27 16 27 37 e20 16 14 13 13 e!2 11 11 11 11 10 9.9 10 9.9 9.8 9.9 15 24 16 12 11 10 9.9 9.9 9.7 389.0 13.9 37 9.7 772 1.41 1.47 FOR WATER YEARS 1967 24.4 62.4 1969 6.66 1977 19.3 48.4 1988 4.04 1977 9.3 9.5 9.1 8.7 e8.4 e8.4 e8.4 e8.1 8.2 7.9 7.9 7.6 7.4 7.5 7.4 9.6 13 9.0 8.4 7.9 8.2 7.3 8.2 10 8.6 7.6 6.9 6.5 6.5 6.5 6.7 254.7 8.22 13 6.5 505 .83 .96 - 1993 14.5 36.2 1969 3.54 1977 1992 CALENDAR YEAR 8558. 23. 376 4. 4. 16980 2. 32. 40 11 5. 2 4 Jan 5 0 Apr 25 6 Apr 22 38 35 9 6.4 6.6 6.7 6.5 6.7 6.9 7.1 9.2 8.3 7.3 7.0 8.1 e!2 ell e9.8 9.6 7.0 6.2 5.8 6.3 9.4 6.6 6.7 6.0 5.9 5.5 5.3 5.6 6.8 41--- 253.3 8.44 41 5.3 502 .86 .96 229 175 30 14 11 9.9 8.9 9.2 42 21 15 10 8.9 8.4 9.8 8.4 7.6 7.4 7.4 6.9 6.9 6.9 8.1 8.4 27 21 39 31 14 12 10 824.1 26.6 229 6.9 1630 2.70 3.12 9.5 8.2 7.9 7.4 6.9 6.6 6.2 5.9 6.3 6.7 6.4 5.8 5.7 6.4 6.3 6.3 5.5 4.9 156 99 16 11 8.9 8.9 7.3 6.5 6.1 5.6 5.3 7.2 --- 456.7 15.2 156 4.9 906 1.55 1.73 6.9 6.2 11 12 6.8 5.4 8.2 12 8.3 5.7 701 52 19 13 18 39 15 11 10 9.8 9.7 92 286 81 36 27 26 19 17 15 14 1593.0 51.4 701 5.4 3160 5.22 6.02 13 12 12 12 11 11 10 9.8 9.5 8.8 8.8 8.5 7.8 7.9 8.3 13 9.9 7.5 6.9 6.5 6.3 6.8 13 8.7 7.2 6.8 6.4 6.5 6.2 6.2 7.2 275.5 8.89 13 6.2 546 .90 1.04 6.7 6.1 5.9 5.5 37 26 13 23 24 12 8.7 7.1 7.0 7.1 6.6 21 39 38 26 19 13 10 10 11 8.9 8.0 12 13 13 102--- 539.6 18.0 102 5.5 1070 1.83 2.04 , BY WATER YEAR (WY) 16.0 53.2 1971 4.66 1984 FOR 1993 8249. 22. 701 4. 5. 4050 9. 4. 16360 2. 31. 39 10 6. 30.5 93.2 1969 4.28 1974 HATER YEAR 5 6 Jul 11 9 Jun 18 8 Jun 12 Jul 11 74 Jul 11 8 Jun 18 30 19 4 19.1 63.7 1970 2.80 1974 19.2 63.7 1979 3.72 1974 WATER 27. 58. 11. 3160 . 1. 15000 13. . 19970 2. 38. 44 12 5. 26.1 137 1979 5.69 1991 YEARS 1967 - 6 0 0 Oct 9 80 Jul 24 5 Jul 18 Sep 13 10 Sep 13 80 Jul 24 80 05 3 32.4 103 1979 5.20 1967 1993 1971 1977 1970 1977 1977 1982 1982 1977 e Estimated 309 mMm»»mm 0638 \ 0635 ; 1 :X, A !': ' •• ••* X •• . . • .,.• • 0655 f~ ; : ' , : ; , t . --- I : 063440 •• '" .. '";' , .'•• _ " . : : 0710 EXPLANATION ;v. A 0670 SURFACE-WATER STATION AND NUMBER T°725 QUALITY-OF-WATER STATION AND NUMBER Figure 21 .--Northeastern river basins the Rio Herrera to Rio Anton Ruiz basins. 370 RIO BSPIRITU SANTO BASIN 50063440 QDBBRADA 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 Bspiritu 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* (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 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV 1 .17 e2.0 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 .16 e3.0 .14 e3.5 .15 e46 .15 el.l .20 .50 .25 .26 .14 .40 .14 .60 .15 e .0 .13 .34 .13 .25 .12 .17 .12 .17 .12 .17 .12 e4.8 .11 e.42 .11 e23 .11 e3.2 .12 e.94 .11 e!7 .12 e43 .11 el. 6 .10 12 .11 1.3 .12 .83 .12 30 .12 21 .12 50 .14 21 31 e2.7 --- TOTAL 6.71 292.55 MEAN ,22 9.75 MAX 2.7 50 MIN .10 .17 AC-FT 13 580 CFSM .21 9.66 IN. .25 10.78 DEC 1.9 .95 .90 28 1.4 9.7 .81 .46 .33 .26 e.25 e.25 e.25 el. 2 el. 2 e.35 e.52 e.69 .74 .85 .47 19 4.3 25 20 61 14 17 70 33 50 364.78 11.8 70 .25 724 11.7 13.44 STATISTICS OF MONTHLY MEAN DATA MEAN 6.23 10.8 MAX 17.1 20.1 (WY) 1986 1985 MIN .22 2.47 (WY) 1993 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 8.43 21.6 1988 .95 1990 FOR JAN 15 12 3.3 2.0 12 e36 e60 e!3 e6.8 e7.8 e5.2 e4.1 e4.1 e3.5 2.9 .91 .20 .10 .12 .07 .04 40 2.8 2.3 29 .84 3.1 12 16 .69 .37 296.24 9.56 60 .04 588 9.46 10.91 FOR WATER 6.61 10.8 1988 3.41 1985 FBB .24 1.2 3.2 .93 .44 .16 .10 .07 .06 .05 .04 9.9 .36 .09 .05 .05 .05 .05 .03 51 e!5 e4.0 el.O e.15 .14 .16 .62 .10 ___ ___ —— 89.24 3.19 51 .03 177 3.16 3.29 YEARS 1983 6.32 12.0 1988 1.59 1992 MAR .06 .13 .07 .04 .03 .03 .02 .15 .03 .01 .01 .01 .01 .01 .05 7.4 1.2 1.6 8.2 .20 .06 .03 15 12 1.4 .59 .39 .28 .18 .14 .10 49.43 1.59 15 .01 98 1.58 1.82 - 1993 5.63 14.7 1990 1.59 1993 1992 CALENDAR YEAR 2399. 6. 147 . . 4760 6. 88. 19 1. 74 56 May 1 09 Jul 7 11 Oct 18 49 39 4 17 APR .09 .09 6.6 .37 .24 .20 .08 .12 16 3.5 .37 .24 17 3.4 1.5 3.2 3.4 .39 .35 .84 1.3 .19 .11 .08 .06 .13 .55 .35 21 59 --- 140.75 4.69 59 .06 279 4.65 5.18 MAY 36 73 13 .55 1.8 3.2 2.7 5.6 16 1.5 1.6 .16 .14 23 .25 .08 .05 .04 .03 .03 .02 .02 .18 .35 27 17 48 2.8 .62 7.5 .47 282.69 9.12 73 .02 561 9.03 10.41 OUN .25 .18 .13 .11 .09 .08 .08 .12 .15 4.1 .34 .14 5.1 .92 2.4 1.4 .25 .52 54 13 el.O e!8 2.1 3.4 .94 .48 .31 .29 1.1 10 120.98 4.03 54 .08 240 3.99 4.46 JUL .34 11 35 2.3 .47 .40 30 9.2 .71 .49 e70 el. 7 .22 2.3 24 10 .20 .09 .12 .08 .03 15 39 14 .58 1.8 1.6 .13 .08 .05 .05 270.94 8.74 70 .03 537 8.65 9.98 AUG .04 .03 .02 .02 .01 .01 .01 .01 .01 .01 .03 .01 .01 .00 .39 6.4 .47 1.5 1.7 .01 .01 3.6 1.7 .02 .01 .02 .01 .00 .00 .09 .29 16.44 .53 6.4 .00 33 .53 .61 SEP .05 .01 .26 4.0 8.6 8.5 11 12 1.8 .67 .06 .08 .15 .43 39 39 8.2 11 3.2 1.4 1.1 3.0 2.2 2.6 .98 1.2 11 12 3.7 6.8 --- 193.99 6.47 39 .01 385 6.40 7.14 , BY WATER YEAR (WY) 5.20 9.99 1987 1.09 1984 FOR 1993 2124. 5. 73 . . 792 7. . 4210 5. 78. 17 B . 8.65 15.9 1992 4.02 1991 WATER YEAR 74 82 May 2 00 Aug 14 01 Aug 4 Sep 15 56 Sep 15 00 Aug 14 76 26 47 03 5.83 13.7 1987 .98 1985 6.85 12.8 1983 2.36 1991 WATER 6 9 4 216 2230 9 5020 6 93 17 2 7.13 14.5 1988 .53 1993 YEARS 1983 .93 .48 .46 Dec .00 Aug .01 Aug Dec .42 Dec . 0 0 Aug .86 .25 .8 .48 6.43 15.6 1989 2.34 1986 - 1993 1988 1991 7 1987 14 1993 4 1993 7 1987 7 1987 14 1993 e Estimated RIO BSPIRITO SANTO BASIN 50063500 QOEBRADA TORONJA AT BL VERDE, PR 311 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 1 (0.166 km'). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—April 1983 to current year. GAGE.—Water-stage recorder, crest-stage gage and concrete broad-V-notch crested weir. Elevation of gage is 876 ft (267 m), from topographic map. REMARKS.—Records poor. Gage-height satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV 1 .21 .24 2 .20 .35 3 .17 .42 4 .19 4.9 5 .21 .23 6 .21 .12 7 .20 .07 8 .18 .08 9 .18 .14 10 .19 .74 11 .17 .09 12 .17 . 07 13 .16 .06 14 .16 .05 15 .16 .06 16 .16 .81 17 .15 .11 18 .15 3.3 19 .15 .56 20 .16 .21 21 .15 1.9 22 .16 6.1 23 .15 .81 24 .14 .59 25 .15 .25 26 .16 .21 27 .16 2.0 28 .16 3.4 29 .15 9.5 30 .17 e9.4 31 .33 TOTAL 5.41 46.77 MEAN .17 1.56 MAX .33 9.5 MTN .14 .05 AC-FT 11 93 CFSM 2.91 26.0 IN. 3.35 29.00 STATISTICS OF MONTHLY MEAN MEAN .32 .69 MAX 1.35 1.56 (WY) 1986 1993 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 DEC e.60 .36 .27 1.4 .26 1.2 .20 .16 .13 .11 .09 .08 .08 .17 .18 .08 .07 .06 .06 .05 .05 .85 .12 .76 1.8 7.6 .81 1.5 8.2 9.8 11 48.10 1.55 11 .05 95 25.9 29.82 DATA .52 1.55 1993 .091 1990 FOR JAN 6.8 3.7 2.1 1.3 1.5 3.4 5.0 1.6 .91 1.0 .74 .59 .59 .51 .40 .39 .27 .20 .19 .17 .15 3.8 .71 .39 4.0 .45 .44 .44 .85 .30 .24 43.13 1.39 6.8 .15 86 23.2 26.74 FEB .26 .46 .68 .32 .24 .24 .23 .21 .20 .19 .22 .52 .23 .20 .21 .23 .23 .23 .22 .49 1.7 e.50 e.27 e.23 e.21 e.21 e.21 e.20 —— 9.34 .33 1.7 .19 19 5.56 5.79 FOR WATER YEARS 1983 .38 1.39 1993 .14 1986 .25 .44 1988 .092 1987 MAR e.19 e.18 e.18 e.43 e.40 e.44 e.36 e.54 e.39 e.24 e.18 e.14 e.20 e.18 e.20 e.28 e.16 e.10 e.19 e.10 e.ll e.08 e.17 e.18 e.09 e.04 e.07 e.09 e.08 e.10 e.10 6.19 .20 .54 .04 12 3.33 3.84 - 1993 .23 .63 1990 .054 1992 1992 CALENDAR YEAR 171.61 .47 11 .03 .04 340 7.81 106.40 .81 .17 .05 Dec 31 Mar 15 Mar 24 APR e.05 e.03 e.03 e.03 e.02 6.02 e.Ol e.03 e.02 e.Ol e.02 e.03 el. 3 e.06 e.02 e.03 e.04 e.04 e.03 e.07 e.07 e.05 e.04 e.04 e.05 e.06 e.06 e.07 e2.9 e3.0 —— 8.23 .27 3.0 .01 16 4.57 5.10 MAY e.22 e!2 e2.3 e.29 e.22 e.34 e.27 el.O el.l 6.31 e.27 e.18 e.19 e.86 e.23 e.19 e.22 6.15 e.ll e.21 e.ll e.25 e.25 e.70 62.5 el. 8 67.5 el.O e.57 e.49 e.37 36.20 1.17 12 .11 72 19.5 22.44 JUN e.19 e.24 e.19 e.18 6.17 e.20 e.21 e.09 e.19 6.17 6.13 6.14 e.21 e.19 e.30 e.21 6.15 e.16 66.3 e2.6 e.45 62.6 e.45 e.55 e.40 e.32 e.30 e.34 e.30 e.48 —— 18.41 .61 6.3 .09 37 10.2 11.41 JUL e.29 e.92 64.1 e.54 6.31 e.33 e5.8 el.l e.44 e.38 ell el. 7 e.77 e.69 e3.5 e3.6 e.67 e.49 e.50 e.40 e.33 el. 2 67.0 63.8 6.81 6.61 e.50 e.34 e.26 6.17 6.12 52.67 1.70 11 .12 104 28.3 32.66 AUG 6.12 e.09 e.07 e.06 e.05 e.03 e.02 e.03 e.04 e.05 e.06 e.05 e.05 e.05 e.06 e.28 e.06 e.06 e.05 e.02 e.03 e.06 e.06 e.03 e.03 e.03 e.03 e.03 e.02 e.04 e.02 1.68 .054 .28 .02 3.3 .90 1.04 SEP e.Ol e.Ol e.03 e.33 e.08 e.04 e.07 e.04 e.02 e.02 e.Ol e.Ol e.07 e.02 el. 7 e2.0 e3.4 e.20 e.07 e.04 e.03 e.03 e.03 e.04 e.04 e.04 e.10 e.10 e.06 e.20 8.84 .29 3.4 .01 18 4.91 5.48 , BY WATER YEAR (WY) .21 .61 1987 .035 1984 FOR 1993 284 12 33 1 565 13 176 1 .41 1.17 1993 .11 1991 WATER YEAR .97 .78 May 2 .01 Apr 7 . 02 Apr 5 Jul 11 .94 Jul 11 .0 .68 .9 .20 .03 .28 .61 1987 .056 1991 .36 1.70 1993 .046 1991 WATER 12 101 2 254 5 79 .28 .54 1988 .054 1993 YEARS 1983 .35 .78 .17 .01 .01 .61 .00 .84 .40 .71 .15 .05 May Apr Aug Aug Aug Apr .29 .61 1989 .060 1991 - 1993 1993 1984 2 1993 10 1983 5 1991 13 1990 13 1990 10 1983 e Estimated 312 RIO ESPIRITU SANTO BASIN 50063800 RIO ESPIRITU SANTO NEAR RIO GRANDE, PR LOCATION.--Lat 18°21'37", 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 Jiminez, and 1.9 mi (3.1 km) southeast of Rio Grande. DRAINAGE AREA.--8.62 mi* (22.33 km'). WATER-DISCHARGE RECORDS PERIOD OF 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 poor. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN PEB MAR APR MAY JUN JUL AUG SEP 1 e20 e!4 2 e20 e!2 3 e!5 elOO 4 e!5 e350 5 e!6 e70 6 e!6 e40 7 el9 e39 8 el5 e25 9 el5 elOO 10 e22 e200 11 e!6 e3S 12 e!5 e40 13 el4 e45 14 el3 e25 15 el3 e25 16 el3 e!40 17 e!3 e80 18 e!4 e220 19 e!4 elOO 20 e40 e80 21 e20 e!50 22 el5 e400 23 e25 elOO 24 el2 ellO 25 e!3 e80 26 el2 e76 27 el3 e350 28 el5 e300 29 el2 e250 30 ell e230 31 e!2 TOTAL 498 3786 MEAN 16.1 126 MAX 40 400 MIN 11 12 AC-FT 988 7510 CFSM 1.86 14.6 IN. 2.15 16.34 STATISTICS OF MONTHLY MEAN MEAN 63.2 87 . 1 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 FLOW INSTANTANEOUS PEAK STAGE ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS e90 e60 e50 e!80 e60 e90 e60 e40 e32 e30 e23 e22 e21 e35 e60 e35 e27 e32 e35 e25 e24 e!30 e50 ellO elSO e400 e!40 elSO e350 e300 el30 2971 95.8 400 21 5890 11.1 12.82 DATA 75.8 179 1971 18.1 1990 FOR e!20 e80 e70 e70 elOO e!30 e220 elOO e70 e56 eS8 e60 e58 e66 e54 e58 e45 e40 e40 e35 e30 e!50 e80 e60 e!70 e62 e90 elOO e220 e60 e40 2592 83.6 220 30 5140 9.70 11.19 e35 e45 e70 e40 e35 e30 e28 e27 e26 e24 e22 e32 e27 e22 e21 e21 e21 e20 e!9 e70 el20 e25 e20 el 9 e!7 e!7 e!7 el6 ___ 886 31.6 120 16 1760 3.67 3.82 FOR WATER YEARS 1966 53.2 119 1969 18.5 1977 50.2 117 1982 10.8 1983 e!6 e!5 e!4 e!4 e!3 e!3 e!2 el4 e!2 el2 e!2 e!2 e!2 ell ell e45 e35 e20 e!4 e!2 e!3 ell e25 e50 el9 e!5 e!4 el2 ell elO elO 509 16.4 SO 10 1010 1.90 2.20 - 1993 40.6 153 1990 13.0 1977 1992 CALENDAR YEAR 20503.5 56.0 1010 5.0 6.1 40670 6.50 88.48 140 21 9.0 May 1 Jul 7 Jul 1 e9.8 e9.8 elS ell elO e!8 elO elO e!9 e!9 ell e!3 e25 e20 e!5 ell e9.8 e9.6 elO e32 e31 e!3 e45 el5 el2 ell e!5 e25 e40 e200 695.0 23.2 200 9.6 1380 2.69 3.00 e300 e350 e90 e40 e28 e30 e32 e33 el60 e50 e3S e25 e23 e30 e25 e20 e!8 e!7 e!7 e!6 el8 e!5 el9 el9 el 6 e60 e!15 e70 e23 e26 e20 1800 58.1 350 15 3570 6.74 7.77 e!7 e!6 e!4 e!3 e!2 e!2 ell e!2 e!5 e25 e!7 ell e!4 e!6 e!5 e!4 ell elO e200 el20 e30 e44 e20 e32 el9 e!7 e!4 e!5 e!4 e40 820 27.3 200 10 1630 3.17 3.54 e!9 e30 e90 e45 e20 e!7 e!70 e90 e30 e20 e500 ellO e35 e30 e80 e90 e29 e25 e22 e20 e!7 elOO e350 el50 e58 e54 e50 e45 e30 e25 e25 2376 76.6 500 17 4710 8.89 10.25 e24 e22 e21 e20 e20 e!8 e!7 e!6 e!6 e!4 e!5 e!4 e!3 e!3 e!5 e46 e25 e!4 e!3 ell elO e!4 e76 e21 e!2 elO e9.2 e9.2 e9.8 e40 e30 608.2 19.6 76 9.2 1210 2.28 2.62 e20 e!2 ell elO e!30 e58 e40 elOO 46 e50 e20 e!3 e!9 el8 e!30 e!60 e!20 e60 e50 e25 e!8 e!6 el6 e25 e!8 e!5 e35 e50 e45 elOO --- 1430 47.7 160 10 2840 5.53 6.17 , BY WATER YEAR (WY) 45.1 119 1981 6.27 1984 FOR 1993 18971. 52. 500 9. 11 37630 6. 81. 124 25 12 70.4 185 1979 14.9 1973 WATER YEAR 2 0 Jul 11 2 Aug 27 Mar 30 03 87 47.1 120 1970 10.0 1975 52.5 114 1983 11.1 1975 WATER 59 98 37 2600 4 4 19200 15 42780 6 93 125 26 11 61.0 123 1988 19.6 1993 YEARS 1966 - .1 .6 .3 Dec 7 . 1 Jul 3 .4 Jun 30 Aug 13 .74 Aug 13 .85 .08 56.8 191 1989 17.7 1971 1993 1979 1974 1987 1975 1975 1990 1990 e Estimated RIO ESPIRITO SANTO BASIN 50063800 RIO ESPIRITO SANTO NEAR RIO GRANOB, PR—Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1958, 1961-66, 1968 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 373 DATE OCT 1992 08... DEC 16... FBB 1993 22. .. APR 15. .. JUN 10... AUG 09... TIME 1250 1055 1155 1200 1230 1200 DIS- CHARGE, INST. CUBIC FEET PER SECOND 14 22 18 15 39 16 SPE- CIFIC CON- DUCT- ANCE (US/CM) 100 106 86 127 130 149 PH WATER WHOLE FIELD (STAND- ARD UNITS) 8.0 7.4 7.0 6.8 6.9 6.8 TEMPER- ATURE WATER (DBG C) 28.5 22.2 21.2 26.0 29.1 28.3 TUR- BID- ITY (NTU) 2.0 4.2 5.1 3.5 2.7 2.9 OXYGEN, DIS- SOLVED (MG/L) 7.8 8.3 8.3 5.5 6.0 5.3 OXYGEN, OXYGEN DIS- DEMAND, SOLVED CHEM- (PBR- ICAL CENT (HIGH SATUR- LEVEL) ATI ON) (MG/L) 100 <10 110 <10 112 19 66 11 76 <10 67 <10 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 240 410 K700 K130 280 3500 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 230 30 290 2200 450 2700 DATE OCT 1992 08... DEC 16... FBB 1993 22... APR 15. .. JUN 10... AUG 09... HARD- NESS TOTAL (MG/L AS CACO3) 40 HARD- NESS NONCARB WH WAT TOT FLD MG/L AS CACO3 0 CALCIUM DIS- SOLVED (MG/L AS CA) 8.8 MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) 4.3 SODIUM, DIS- SOLVED (MG/L AS NA) 8.7 30 1 6.3 3.4 7.1 44 0 9.5 4.9 9.6 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) CACO3 0.6 0.50 0.6 0.70 0.6 5.5 43 30 21 33 23 47 CHLO- SULFATB RIDE, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS S) AS SO4) AS CL) cO.S 1.7 10 <O.S 2.4 10 1.9 15 SOLIDS, RESIDUE FLUO- SILICA, RIDE, DIS- DIS- SOLVED SOLVED (MG/L DATE (MG/L AS AS F) SIO2) OCT 1992 08... <0.10 22 DEC 16... FEB 1993 22... APR 15... <0.10 18 JUN 10... AUG 09... <0.10 23 SUM OF SOLIDS, TOTAL CONSTI- DIS- AT 105 TUENTS, SOLVED DBG. C, DIS- (TONS SUS- SOLVBD PER FENDED (MG/L) DAY) (MG/L) 82 3.18 3 <1 <1 68 2.81 12 9 100 4.32 7 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) 0.080 0. 0.160 0. <0. <0. <0. <0. 020 140 010 010 010 010 0 0 0 0 0 0 .100 .300 .100 .100 .100 .100 NITRO- NITRO- GEN, GEN, AMMONIA ORGANIC TOTAL TOTAL (MG/L (MG/L AS N) AS N) 0. 5. 0. 0. 0. 0. 040 80 010 040 010 010 0. 2. 0. 0. 0. 0. 36 40 19 26 29 19 non-ideal count 314 DATE OCT 1992 08... DEC 16.. . FEB 1993 22... APR 15.. . JUN 10... AUG 09.. . DATE OCT 1992 08... DEC 16.. . FBB 1993 22... APR 15.. . JUN 10... AUG 09.. . RIO ESPIRITO SANTO BASIN 50063800 RIO ESPIRITU SANTO NEAR RIO GRANDB, PR—Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 NITRO- OBN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.40 8.2 0.20 0.30 0.30 0.20 IRON, TOTAL RECOV- ERABLE (UG/L AS PE) NITRO- GEN, TOTAL (MG/L AS N) — 8.5 — — — — LEAD, TOTAL RECOV- ERABLE (DG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N03) -- 32 -- -- -- -- MANGA- NESE, TOTAL RECOV- ERABLE (OG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.040 1.50 0.010 <0.010 0.080 <0.010 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) 30 -- -- 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) 12 — — <10 — — METHY- LBNB BLUE ACTIVE SUB- STANCE (MG/L) 180 160 <1 20 10 <0.10 <0.10 <1 <1 <1 <1 20 <0.010 <0.010 <1 0.01 0.02 RIO BSPIRITU SANTO BASIN 50064200 RIO GRANDS NEAR EL VBROB, PR 375 LOCATION.—Lat 18020'54", long 65<>50'30", Hydrologic Unit 21010005, on left bank 250 ft (7.6 m) 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 El Verde, and 2.7 mi (4.3 km) south of Rio Grande. DRAINAGE AREA.--7.31 mi' (18.93 km9 ). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--May 1967 to December 1970, January 1972 to September 1982, August 1990 to current year. GAGE.—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 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 13 8.5 2 13 7.7 3 9.7 54 4 9.5 197 5 10 44 6 9.9 22 7 12 21 8 10 12 9 10 28 10 14 91 11 10 17 12 9.3 20 13 8.7 24 14 8.7 13 15 8.5 13 16 8.5 67 17 8.7 35 18 9.2 109 19 9.3 47 20 22 35 21 9.3 82 22 8.1 225 23 15 64 24 8.6 68 25 7.4 45 26 7.1 41 27 7.6 189 28 8.6 144 29 7.0 124 30 7.1 112 31 7.4 --- TOTAL 307.2 1959.2 MEAN 9.91 65.3 MAX 22 225 MIN 7.0 7.7 AC-FT 609 3890 CFSM 1.36 8.93 IN. 1.56 9.97 STATISTICS OF MONTHLY MEAN MEAN 64.1 73.7 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 43 33 29 98 42 56 27 22 20 18 17 16 15 20 42 19 16 22 23 15 14 73 29 74 97 225 72 97 198 159 92 1723 55.6 225 14 3420 7.60 8.77 DATA 51.8 140 1971 13.8 1968 FOR 85 49 44 45 67 82 134 57 43 33 34 35 32 37 29 31 24 22 22 20 18 85 54 32 105 34 55 72 145 33 24 1582 51.0 145 18 3140 6.98 8.05 21 28 48 26 21 19 18 17 16 15 14 20 17 14 13 13 13 13 12 52 77 24 14 12 11 11 11 10 ___ ___ —— 580 20.7 77 10 1150 2.83 2.95 FOR WATER YEARS 1967 44.0 151 1969 10.1 1977 31.3 76.4 1969 5.80 1977 9.7 9.3 9.1 8.8 8.4 8.3 8.1 8.6 7.9 7.6 7.4 7.2 7.1 7.3 7.0 27 21 12 8.7 7.5 7.9 6.7 17 33 12 9.3 8.7 6.8 6.3 6.2 6.4 318.3 10.3 33 6.2 631 1.40 1.62 - 1993 22.5 54.4 1969 4.50 1977 1992 CALENDAR YEAR 11346 31 405 3 4 22510 4 57 71 16 6 .3 .0 May 1 .7 Apr 27 .1 Apr 22 .24 .74 .5 5.6 5.6 9.4 7.3 5.9 11 5.8 5.8 11 11 5.9 7.2 15 11 8.9 7.5 6.2 5.4 5.3 19 18 7.2 27 9.9 6.5 6.1 7.2 14 22 137 —— 424.7 14.2 137 5.3 842 1.94 2.16 208 218 54 24 17 19 20 20 100 33 21 16 14 22 16 12 11 11 10 9.8 11 9.5 12 12 47 37 87 32 14 16 12 1145.3 36.9 218 9.5 2270 5.05 5.83 10 9.6 8.5 7.9 7.3 7.1 6.7 7.1 8.0 12 10 6.8 8.7 10 8.9 8.2 6.7 6.1 138 78 16 28 14 20 12 9.6 8.8 9.2 8.9 26 —— 518.1 17.3 138 6.1 1030 2.36 2.64 11 16 63 23 11 9.9 103 51 17 12 373 50 22 17 50 56 18 14 13 12 10 67 210 109 34 33 29 23 15 14 14 1499.9 48.4 373 9.9 2980 6.62 7.63 12 11 11 10 10 9.7 9.0 9.0 8.4 7.8 8.1 7.5 6.9 6.7 8.1 26 13 7.4 6.9 6.2 5.7 7.8 41 9.0 6.5 6.7 5.5 5.3 5.6 23 17 327.8 10.6 41 5.3 650 1.45 1.67 9.8 6.8 6.2 5.3 75 31 23 61 27 30 12 7.3 11 10 75 90 72 37 23 11 9.9 9.3 13 15 8.3 7.3 32 30 24 63___ 835.2 27.8 90 5.3 1660 3.81 4.25 , BY WATER YEAR (WY) 30.3 119 1978 8.55 1975 FOR 1993 11220 30 373 5 6 2980 11 4 22260 4 57 75 14 7 58.8 203 1969 10.2 1974 WATER YEAR .7 .7 Jul 11 .3 Apr 19 .5 Mar 27 Jul 11 .62 Jul 11 .8 Aug 27 .21 .10 .1 33.2 86.5 1968 6.22 1975 38.6 109 1969 9.05 1991 WATER 43 87 25 3470 2 2 17400 15 1 31410 5 80 84 18 7 44.5 90.0 1968 7.39 1991 YEARS 1967 .4 .1 .8 May .2 Aug .5 Aug Sep .50 Sep .6 Mar .93 .58 .2 49.6 153 1975 12.4 1967 - 1993 1969 1991 21 1969 15 1991 10 1991 16 1975 16 1975 13 1977 3/6 RIO MAMEYES BASIN 50065500 RIO MAMEYES NEAR SABANA, PR LOCATION.--Lat 18°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 9 (17.82 km'). HATER-DISCHARGE RECORDS PERIOD OF RECORD.--August 1967 to December 1973, June 1983 to current year. GAGE.—Hater-stage recorder and crest-stage gage. Elevation of gage is 275 ft (84 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 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 22 40 2 19 51 3 17 84 4 23 331 5 25 68 6 49 65 7 28 48 8 25 40 9 26 48 10 26 141 11 21 36 12 22 39 13 20 35 14 19 49 15 18 39 16 19 85 17 19 62 18 19 181 19 19 65 20 31 79 21 21 70 22 46 199 23 30 68 24 21 63 25 20 53 26 19 40 27 19 101 28 18 108 29 25 145 30 27 105 31 61 TOTAL 774 2538 MEAN 25.0 84.6 MAX 61 331 MIN 17 35 AC-PT 1540 5030 CPSM 3.63 12.3 IN. 4.18 13.72 STATISTICS OF MONTHLY MEAN MEAN 68.7 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 52 44 42 80 41 86 37 33 30 28 28 25 25 28 35 26 23 25 24 24 23 71 31 68 70 246 73 87 678 262 146 2491 80.4 678 23 4940 11.7 13.47 DATA 62.9 164 1971 16.6 1990 FOR 108 89 67 e56 e94 e96 e72 e54 e46 e46 e45 e43 50 52 47 45 34 29 29 27 24 174 54 34 104 36 57 105 178 62 53 2010 64.8 178 24 3990 9.42 10.87 46 47 50 48 42 39 37 35 32 31 30 97 44 34 30 27 28 28 25 161 129 42 60 40 32 e30 e32 e28 ___ ___ —— 1304 46.6 161 25 2590 6.77 7.05 FOR HATER YEARS 1967 55.2 105 1969 25.0 1985 41.0 68.0 1988 21.7 1968 e28 e39 e32 e26 25 24 24 29 23 22 21 20 26 21 25 83 45 32 68 34 26 22 76 95 35 40 28 29 24 23 24 1069 34.5 95 20 2120 5.01 5.78 - 1993 39.5 79.7 1990 18.1 1968 1992 CALENDAR YEAR 21127 57.7 754 16 19 41910 8.39 114.23 106 39 20 May 1 Apr 6 Feb 29 28 26 51 24 25 23 20 19 62 35 22 22 31 26 22 38 36 51 32 43 32 21 20 18 19 28 32 34 65 526 —— 1431 47.7 526 18 2840 6.93 7.74 145 250 127 46 43 32 32 74 e205 e62 e35 e27 e27 159 46 35 30 30 e28 e33 e31 e28 e28 e31 92 50 236 65 40 59 68 2194 70.8 250 27 4350 10.3 11.86 75 53 48 44 39 37 42 41 42 74 37 32 66 39 74 49 31 37 274 e!26 e43 77 42 39 44 51 39 33 45 89 --- 1762 58.7 274 31 3490 8.54 9.53 34 51 121 42 39 36 105 93 66 49 342 78 59 83 158 152 80 69 60 50 46 101 218 103 69 73 66 50 47 47 48 2635 85.0 342 34 5230 12.4 14.25 50 56 53 51 47 46 46 44 42 44 47 41 37 34 45 76 54 69 73 43 34 53 66 38 32 30 27 29 28 39 65 1439 46.4 76 27 2850 6.75 7.78 e32 e50 e45 e84 e45 ellO elOO e52 e49 e35 e38 e36 e35 e27 e60 e400 elOO e92 e30 e26 e24 e23 e28 e22 e52 e21 e40 e30 e46 e52 --- 1784 59.5 400 21 3540 8.64 9.65 , BY HATER YEAR (WY) 42.1 83.1 1973 14.5 1984 FOR 1993 21431 58. 678 17 19 10600 10. 16 42510 8. 115. 102 42 23 68.9 147 1970 18.7 1973 HATER YEAR 7 Dec 29 Oct 3 Oct 13 Dec 29 38 Dec 29 Oct 3 53 88 57.2 112 1970 12.4 1985 51.7 93.4 1969 20.5 1971 HATER 57. 78. 41. 2780 6. 9. 20500 13. 5. 41890 8. 114. 104 34 16 54.6 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 41 20 57.3 166 1989 26.6 1986 1993 1971 1972 1989 1970 1985 1989 1989 1970 e Estimated 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 Luquillo. DRAINAGE AREA.--3.96 mi> (10.26 km'). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—October 1979 to current year. GAGE.—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 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES 317 DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 8.9 11 2 7.4 17 3 7.0 14 4 8.6 183 5 15 25 6 74 17 7 12 16 8 11 13 9 12 12 10 9.3 28 11 7.5 11 12 7.7 11 13 7.7 18 14 7.2 44 15 7.5 19 16 7.5 30 17 13 19 18 9.9 66 19 7.2 25 20 7.7 32 21 6.6 21 22 7.0 50 23 6.8 22 24 6.6 18 25 6.6 16 26 6.5 15 27 6.5 35 28 6.2 55 29 10 73 30 11 49 31 37 --- TOTAL 358.9 965 MEAN 11.6 32.2 MAX 74 183 MIN 6.2 11 AC-FT 712 1910 CFSM 2.92 8.12 IN. 3.37 9.07 STATISTICS OF MONTHLY MEAN MEAN 21.9 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 20 18 18 20 15 43 15 14 13 12 13 11 13 19 17 14 11 12 14 12 11 26 13 19 20 140 25 22 454 152 38 1244 40.1 454 11 2470 10.1 11.69 DATA 25.3 64.1 1982 3.92 1990 FOR 29 24 21 18 32 36 27 17 14 14 13 13 12 15 13 14 13 12 12 12 12 46 22 14 20 14 18 63 61 19 16 666 21.5 63 12 1320 5.43 6.26 15 16 17 16 14 14 13 13 12 12 13 29 18 13 11 11 11 12 11 14 24 11 11 10 9.1 8.7 8.7 7.9 ___ ___ ... 375.4 13.4 29 7.9 745 3.39 3.53 FOR WATER YEARS 1980 13.2 33.0 1992 6.12 1986 11.8 22.2 1988 2.94 1983 7.4 8.1 6.9 6.4 5.9 5.7 5.2 5.3 4.8 5.4 3.9 3.9 4.7 3.9 3.7 9.7 5.2 3.6 7.7 3.4 2.8 2.6 3.3 7.2 3.5 2.9 2.6 2.7 2.7 2.5 2.3 145.9 4.71 9.7 2.3 289 1.19 1.37 - 1993 12.1 36.0 1987 3.78 1980 1992 CALENDAR YEAR 8002.7 21.9 454 2.2 2.9 15870 5.52 75.18 36 11 6.2 Dec 29 Apr 28 Apr 22 2.3 2.3 2.8 2.4 2.6 2.3 e2.6 e2.6 e2.6 e2.2 e2.4 e2.2 e2.2 e2.1 e2.1 e2.6 e3.0 e40 e6.0 e4.0 e2.3 2.0 2.0 2.0 1.9 2.1 2.8 2.3 6.1 278 392.8 13.1 278 1.9 779 3.31 3.69 27 33 18 8.7 12 7.1 4.5 127 185 26 17 9.0 7.2 27 8.5 6.4 5.8 17 6.1 6.0 5.5 5.4 6.5 21 31 13 126 22 10 10 8.0 816.7 26.3 185 4.5 1620 6.65 7.67 10 6.9 6.3 5.9 5.5 5.4 5.2 5.6 6.0 15 5.9 6.6 20 12 18 12 5.9 5.8 241 65 13 18 10 8.5 7.8 7.4 6.9 7.4 8.5 21—— 572.5 19.1 241 5.2 1140 4.82 5.38 7.6 8.9 29 9.7 6.9 7.2 35 20 8.8 7.5 234 23 12 11 74 59 14 11 10 9.1 8.8 36 170 25 15 12 11 9.9 9.3 8.8 8.6 912.1 29.4 234 6.9 1810 7.43 8.57 8.1 7.6 7.2 7.0 6.7 6.6 6.5 6.1 6.3 6.3 5.9 5.4 5.3 5.0 5.8 9.0 6.0 19 15 5.1 4.6 5.0 7.9 7.9 4.7 4.2 4.1 4.1 4.1 5.3 12 213.8 6.90 19 4.1 424 1.74 2.01 10 3.8 5.0 10 17 7.3 78 34 13 6.5 5.8 7.3 6.2 4.8 8.6 212 16 14 8.1 6.5 5.9 6.3 12 9.1 24 8.3 15 13 53 46 666.5 22.2 212 3.8 1320 5.61 6.26 , BY WATER YEAR (WY) 12.9 33.5 1990 2.20 1984 FOR 1993 7329 20 454 1 2 4840 16 14540 5 68 34 11 3 34.6 63.9 1982 14.8 1990 WATER YEAR .6 .1 Dec 29 .9 Apr 25 .2 Apr 21 Dec 29 .11 Dec 29 .07 .85 .6 21.8 50.6 1987 4.70 1985 15.6 31.3 1989 5.84 1986 WATER 19 28 11 887 1 9600 19 14270 4 67 36 8 2 17.0 32.7 1988 6.39 1985 YEARS 1980 .7 .2 .9 Sep .96 Apr .0 Apr Jan .74 Jan .86 Apr .97 .59 .7 .9 17.1 56.3 1989 7.23 1987 - 1993 1988 1984 18 1989 10 1983 6 1983 5 1992 5 1992 17 1983 e Estimated 3 18 RIO PAJARDO BASIN 50071000 RIO PAJARDO NEAR PAJARDO, PR LOCATION.--Lat 18«17'56", long 65°41'42", Hydrologic Unit 21010005, on left bank off Highway 976, 0.1 ml (0.2 km) upstream from Highway 977 bridge, 0.3 mi (0.5 km) downstream from Quebrada Pefion, 1.1 mi (1.8 km) northeast of Colonia Paraiso, and 3.3 mi (5.3 km) southwest of Pajardo. 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 followst 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 ftVs (0.255 mVs) Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 35 25 2 21 59 3 16 90 4 e!5 245 5 e30 61 6 e!20 71 7 e21 57 8 e!9 28 9 e24 42 10 e!7 91 11 e!4 24 12 e!4 23 13 e!3 22 14 e!3 73 15 e!3 77 16 e24 143 17 e29 70 18 e!7 268 19 ell 101 20 e!8 90 21 ell 63 22 e!2 242 23 e8.9 80 24 e9.0 65 25 e8.0 39 26 e7.4 32 27 6.6 185 28 6.4 235 29 7.6 186 30 18 180 31 68 TOTAL 646.9 2967 MEAN 20.9 98.9 MAX 120 268 MIN 6.4 22 AC-FT 1280 5890 CFSM 1.40 6.64 IN. 1.62 7.41 STATISTICS OF MONTHLY MEAN MEAN 96.9 106 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 ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 67 54 53 65 51 283 73 57 51 47 45 42 41 56 51 40 38 36 36 39 35 86 46 85 78 406 107 122 1370 391 146 4097 132 1370 35 8130 8.87 10.23 DATA 81.3 237 1976 14.9 1990 FOR 106 87 72 65 133 90 59 46 45 35 34 34 32 40 29 29 26 24 24 22 21 142 51 26 36 24 34 199 120 23 18 1726 55.7 199 18 3420 3.74 4.31 15 14 16 16 14 12 12 11 11 10 9.6 30 14 11 9.5 9.5 10 14 10 90 70 14 13 11 9.5 9.2 10 8.7 ___ ___ 484.0 17.3 90 8.7 960 1.16 1.21 FOR WATER YEARS 1961 45.3 101 1969 15.4 1977 37.1 80.4 1982 10.8 1983 8.7 12 10 8.1 7.9 7.9 7.6 7.5 7.2 6.9 7.2 7.9 8.3 7.9 7.9 61 35 23 35 26 e!9 e!7 e58 e72 25 35 21 21 19 31 19 640.0 20.6 72 6.9 1270 1.39 1.60 - 1993 35.7 109 1987 9.70 1977 1992 CALENDAR YEAR 20160.3 55.1 1370 4.0 4.8 39990 3.70 50.33 118 22 7.4 Dec 29 Apr 5 Jul 1 16 15 20 16 14 13 12 14 14 14 12 13 12 12 11 14 16 215 28 32 21 12 11 9.6 8.9 9.0 11 11 9.2 651 1266.7 42.2 651 8.9 2510 2.83 3.16 159 128 57 19 26 20 12 166 478 44 27 10 9.7 56 13 10 9.9 43 9.5 9.0 8.9 8.5 11 25 61 30 312 57 23 19 27 1888.5 60.9 478 8.5 3750 4.09 4.71 31 14 12 12 11 11 10 10 11 19 13 11 27 16 24 24 13 15 401 157 38 80 29 25 21 19 17 16 28 55 1170 39.0 401 10 2320 2.62 2.92 19 18 84 25 18 24 65 60 22 17 641 103 37 24 132 113 28 21 18 15 13 125 445 103 57 59 47 37 32 31 29 2462 79.4 641 13 4880 5.33 6.15 27 27 26 25 24 23 22 21 24 21 22 20 19 19 25 48 26 23 40 20 19 17 38 30 19 17 15 18 15 64 36 790 25.5 64 15 1570 1.71 1.97 40 23 44 39 131 38 212 183 52 46 31 29 31 22 102 e743 71 61 20 14 13 12 16 13 39 12 32 18 35 47 2169 72.3 743 12 4300 4.85 5.42 , BY WATER YEAR (WY) 46.1 129 1963 4.02 1984 FOR 1993 20307. 55. 1370 6. 7. 40280 3. 50. 116 24 10 96.0 399 1979 17.7 1973 WATER YEAR 1 6 Dec 29 4 Oct 28 5 Mar 5 73 70 61.2 166 1962 10.0 1985 51.4 132 1969 12.5 1992 WATER 67. 140 38. 8800 1. 1. 48770 4. 61. 128 34 12 57.9 159 1979 25.5 1993 YEARS 1961 - 3 2 Sep 18 0 May 6 5 Apr 18 52 39 86.9 421 1989 19.1 1991 1993 1979 1972 1989 1984 1984 e Estimated RIO FAJARDO BASIN 50071000 RIO FAJARDO NEAR FAJARDO, PR—Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--Hater years 1960 to current year. WATER-QUALITY DATA, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 319 DATE OCT 1992 15... DEC 03... FBB 1993 26... APR 29... JUN 18... AUG 13... TIME 1240 1100 1215 1225 1230 1230 DIS- CHARGE, INST. CUBIC FEET PER SECOND 13 50 20 8.8 16 20 SPE- CIFIC CON- DUCT- ANCE (US/CM) 120 108 150 155 153 116 PH HATER WHOLE FIELD (STAND- ARD UNITS) 7.9 7.6 7.8 7.2 7.0 6.6 TEMPER- ATURE HATER (DBG C) 30.5 25.9 24.5 29.5 30.0 30.5 TUR- BID- ITY (NTU) 1.3 4.3 0.90 0.60 0.40 0.70 OXYGEN, DIS- SOLVED (MG/L) 8.5 8.4 8.0 7.1 7.5 6.9 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 110 105 101 93 99 90 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) <10 <10 13 13 <10 19 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K130 220 30 280 480 K150 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) K100 480 K110 K150 330 230 DATE OCT 1992 15... DEC 03... FBB 1993 26... APR 29... JUN 18... AUG 13... HARD- NESS TOTAL (MG/L AS HARD- NESS NONCARB WH HAT 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 HAT WH TOT FET FIELD MG/L AS SULFIDB TOTAL (MG/L SULFATB DIS- SOLVED (MG/L CHLO- RIDE, DIS- SOLVED (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) 20 1 4.4 2.3 7.4 33 0 7.3 3.6 11 32 2 6.9 3.5 13 AS K) 0.7 1.2 0.8 1.1 1 1.3 CACO3 39 36 100 34 40 52 AS S) AS S04) AS CL) <0.5 7.1 9.0 0.6 4.6 14 3.6 14 SOLIDS, RESIDUE DATE OCT 1992 15... DEC 03... FBB 1993 26... APR 29... JUN 18... AUG 13... FLUO- RIDB, DIS- SOLVED (MG/L AS F) <0.10 -- -- <0.10 -- 0.20 SILICA, DIS- SOLVED (MG/L AS SI 02) 16 — — 26 -- 27 SUM OP CONSTI- TUENTS, DIS- SOLVED (MG/L) 60 -- -- 88 -- 101 SOLIDS, DIS- SOLVED (TONS PER DAY) 3.24 — -- 2.09 — 5.44 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) <1 <1 <1 <1 5 2 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.120 0.890 0.370 0.230 0.380 0.190 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.080 0.210 0.030 0.070 0.020 0.010 NITRO- GEN, N02+N03 TOTAL (MG/L AS N) 0.200 1.10 0.400 0.300 0.400 0.200 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.030 0.400 0.480 0.290 0.450 0.570 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.10 0.20 0.20 0.01 0.05 0.03 non-ideal count 320 DATE OCT 1992 15... DEC 03.. . FEB 1993 26.. . APR 29... JUN 18... AUG 13... RIO FAJARDO BASIN 50071000 RIO FAJARDO NEAR FAJARDO, PR—Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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) 0.40 0.60 0.50 0.30 0.60 0.50 AS N) AS N03) AS P) 0.60 1.1 0.20 0.10 0.40 0.90 1.8 4.9 2.3 1.9 2.7 4.0 0.030 0.040 <0.010 <0.010 0.040 0.030 AS AS) AS BA) AS B) AS CD) AS CR) AS CU) <100 30 2 <100 30 <10 DATE OCT 1992 15.. . DEC 03... FBB 1993 26... APR 29... JUN 18... AUG 13... 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) METHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 2100 70 <1 50 <10 <0.10 <0.10 <1 <1 <1 <1 60 <0.010 <10 <0.010 0.04 0.02 PESTICIDE ANALYSES DATE JUN 1993 09... TIME 1030 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 <0.010 DI- AZINON, TOTAL (UG/L) DI- BNDO- BLDRIN SULFAN, TOTAL TOTAL (UG/L) (UG/L) <0.01 <0.010 <0.010 BNDRIN WATER UNFLTRD BTHION, DATE REC TOTAL (UG/L) (UG/L) JUN 1993 09.. . HEPTA- HBPTA- CHLOR CHLOR, EPOXIDE 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 METH- OXY- CHLOR, TOTAL (UG/L) <0.01 METHYL PARA- THION, TOTAL (UG/L) <0.01 MIREX, TOTAL (UG/L) <0.01 DATE JUN 1993 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 <0.01 <0.01 <0.01 <0.01 <0.01 321 RIO FAJARDO BASIN 50072500 RIO FAJARDO BELOW FAJARDO, PR HATER-QUALITY RECORDS LOCATION.--Lat 18°19'35", long 65038'47", 1.2 ml (1.9 km) southwest of Playa de Fajardo, and east of Fajardo plaza. DRAINAGE AREA.--23.4 mi* (60.6 km1 ). PERIOD OF RBCORD.--Hater years 1974 to current year. HATER-QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 0.5 ml (0.8 km) DATE OCT 1992 15... DEC 03... FBB 1993 26... APR 29... JUN 18. .. AUG 13... TIME 0855 1245 1345 1345 1335 1420 DIS- CHARGE, INST. CUBIC FEET PER SECOND 23 26 32 56 12 16 SPE- CIFIC CON- DUCT- ANCE (US/CM) 144 140 150 193 178 148 PH HATER WHOLE FIELD (STAND- ARD UNITS) 7.0 7.4 7.2 6.8 7.2 6.8 TEMPER- ATURE HATER (DBG C) 28.5 26.0 25.5 29.0 30.5 30.5 TUR- BID- ITY (NTU) 2.6 2.9 6.7 12 0.70 0.70 OXYGEN, DIS- SOLVED (MG/L) 6.5 8.2 8.2 8.5 6.3 5.0 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 82 92 93 110 82 65 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) <10 49 49 12 13 23 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 250 460 460 370 480 380 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) K2100 780 780 220 530 290 DATE OCT 1992 15. .. DEC 03. .. FEB 1993 26... APR 29... JUN 18... AUG 13... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH HAT DIS- (HG/L TOT FLD SOLVED AS MG/L AS (MG/L CAC03) CACO3 40 36 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS NA) 38 3 8.5 4.0 10 8.9 4.3 14 7.7 4.0 14 SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY CHLO- SIUM, HAT 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) 0.7 1.8 1.3 1.3 CACO3 44 43 43 41 44 67 AS S) AS S04) AS CL) <0.5 0.6 8.2 16 6.6 16 4.8 16 SOLIDS, RESIDUE DATE OCT 1992 15.. . DEC 03.. . FBB 1993 26.. . APR 29... JUN 18... AUG 13... FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.10 -- -- 0.10 -- 0.10 SILICA, DIS- SOLVED (MG/L AS SI02) 21 — -- 23 -- 25 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 91 -- -- 99 -- 113 SOLIDS, DIS- SOLVED (TONS PBR DAY) 5.7 — — 15.0 -- 4.9 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) <1 6 10 14 4 2 NITRO- GEN, NITRATE TOTAL (MG/L AS N) -- 0.280 0.360 0.980 0.440 0.190 NITRO- GEN, NITRITE TOTAL (MG/L AS N) <0.010 0.020 0.040 0.020 0.060 0.010 NITRO- GEN, N02+N03 TOTAL (MG/L AS N) <0.050 0.300 0.400 1.00 0.500 0.200 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.150 0.120 0.130 0.140 0.130 0.150 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.15 0.38 0.57 0.06 0.77 0.35 non-ideal count 322 DATE OCT 1992 IS... DEC 03... FEB 1993 26... APR 29... JDN 18... AUG 13... DATE OCT 1992 15... DEC 03... FEB 1993 26... APR 29... JDN 18... AUG 13... RIO PAJARDO BASIN S0072SOO RIO PAJARDO BELOW PAJARDO, PR--Continued HATER-QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.30 O.SO 0.70 0.20 0.90 O.SO IRON, TOTAL RECOV- ERABLE (UG/L AS FE) NITRO- GEN, TOTAL (MG/L AS N) 1.1 0.90 0.40 0.40 1.4 0.70 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS NO3) 4.9 2.5 1.8 6.2 3.1 4.6 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MM) PHOS- PHORUS TOTAL (MG/L AS P) 0.060 O.SOO 0.010 0.010 0.010 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) SO — — 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) 11 — — <1 -- -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) 30 -- -- <10 — -- MBTHY- LENB BLUE ACTIVE SUB- STANCE (MG/L) 2700 730 300 70 0.20 <0.10 40 <0.010 20 <0.010 0.04 0.02 RIO BLANCO BASIN 323 50074950 QUBBRADA GOABA NEAR NAGUABO, PR LOCATION.--Lat 18«17'02", long 65«47'20 I> , Hydrologic Unit 21010005, on right bank, off Highway 191 at Bl Yunque Caribbean National Forest, 4.8 mi (7.7 km) southeast of Campamento Eliza Colberg, 1.3 mi (2.1 km) southeast of Mt. Britton, 2.0 mi (3.2 km) northwest of Pico del Bste and 7.3 mi (11.7 km) southeast of Rio Grande Plaza. DRAINAGE AREA.--0.05 mi> (0.13 km»). HATER-DISCHARGE RECORDS PERIOD OF RECORD.—June 1992 to current year. GAGE.—Hater-stage recorder. Elevation of gage is 2,100 ft (640 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 JUL AUG SEP 1 .60 .64 .31 2 .59 .76 .29 3 .60 .67 .35 4 .63 .97 .40 5 .66 3.4 .38 6 ,68 1.8 .37 7 .66 .59 .35 8 1.4 .43 .28 9 1.1 .30 .50 10 .95 .30 .28 11 .76 .88 .29 12 .80 .31 .24 13 .82 .57 .19 14 .83 .72 .23 15 .84 .37 .35 16 6.1 .34 .63 17 2.7 .38 .51 18 1.7 .31 .43 19 1.4 .33 .47 20 1.2 .30 1.7 21 1.1 .22 .68 22 .96 .18 .36 23 e.61 .86 .20 .50 24 .60 1.4 .25 .39 25 .59 1.3 .16 .26 26 .57 1.0 .26 .20 27 .62 1.3 .28 .16 28 .61 1.1 .22 .15 29 .59 .90 .23 .14 30 .64 .85 .33 .15 31 —— .79 .67 TOTAL —— 36.58 17.37 11.54 MEAN —— 1.18 .56 .38 MAX —— 6.1 3.4 1.7 MIN —— .59 .16 .14 AC-FT —— 73 34 23 CFSM —— 9.83 4.67 3.21 IN. —— 11.34 5.38 3.58 STATISTICS OF MONTHLY MEAN DATA FOR HATER YEARS 1992 - 1992, BY HATER YEAR (WY) MEAN —— 1.18 .56 .38 MAX —— 1.18 .56 .38 (WY) —— 1992 1992 1992 MIN —— 1.18 .56 .38 (WY) —— 1992 1992 1992 e Estimated 324 DAY OCT RIO BLANCO BASIN 50074950 QUBBRAOA GUABA NEAR NAGUABO, PR—Continued DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES NOV DEC JAN FEE MAR APR MAY JUN JUL AUQ SEP 1 .20 .40 2 .18 .94 3 .17 1.1 4 .16 2.7 5 .15 .62 6 .23 .45 7 .20 .29 8 .17 .41 9 .21 .38 10 .19 1.2 11 .18 .30 12 .17 .46 13 .18 .36 14 .20 .32 IS .21 .26 16 .24 1.0 17 .27 .35 18 .28 1.0 19 .26 .29 20 .30 .95 21 .30 .56 22 .77 1.6 23 .41 .38 24 .28 .46 25 .27 .38 26 .30 .28 27 .27 1.3 28 .26 .87 29 .25 2.3 30 .25 e.98 31 .37 TOTAL 7.88 22.89 MEAN .25 .76 MAX .77 2.7 MIN .15 .26 AC-FT 16 45 CFSM 2.12 6.36 IN. 2.44 7.10 e.37 e.34 e.37 e.74 e.40 e el.l e.34 e.31 e.30 e.29 e.29 e.29 e.29 e.31 e.31 e.28 e.29 e.30 e.29 e.30 e.34 .60 e.29 .54 e.31 .54 e.31 .40 e.31 .1 e.28 .80 e.27 .78 e.26 .44 e.26 .41 e.25 .41 e.24 .41 e.24 .37 e.40 .44 e.26 .41 e.23 .34 e.22 .44 e.21 .34 e.20 .34 e.20 .34 e.19 .31 el. 6 .30 e.60 e.27 el. 8 e.29 .45 .53 1.2 2.3 .34 .42 e.27 .36 e.25 .68 e.24 .31 e.25 .54 e.25 e.49 e .3 e.23 e.74 e4.0 e.72 .90 .36 .30 18.89 17.03 8.91 .61 4.0 .27 37 .55 .32 1.8 1.6 .30 .19 34 18 5.08 4.58 2.65 5.86 5.28 2.76 STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1992 - MEAN .25 .76 MAX .25 .76 (WY) 1993 1993 MIN .25 .76 (WY) 1993 1993 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 .61 .61 .55 .32 .55 .32 1993 1993 1993 .61 .55 .32 1993 1993 1993 FOR 1993 157. , 4. . . 64 10. 312 3. 48. . ^ . .22 .28 .26 .25 .25 .25 .24 .27 .25 .24 .22 .23 .26 .21 .21 .73 .40 .19 .20 .39 .24 .19 .58 .49 .30 .41 .27 .24 .22 .25 .22 8.96 .29 .73 .19 18 2.41 2.78 .22 .22 .49 .24 .26 .24 .23 .24 .24 .23 .21 .24 .22 .22 .20 .19 .16 .17 .38 .59 .31 .20 .18 .20 .20 .26 .23 .40 .34 2.2 —— 9.71 .32 2.2 .16 19 2.70 3.01 1993, BY WATER .29 .29 1993 .29 1993 .32 .32 1993 .32 1993 3.9 2.3 .60 .34 .33 .31 .27 .74 .94 .43 .43 .35 .33 .61 .31 .28 .27 .26 .27 .26 .24 .23 .25 .25 .81 .45 1.7 .43 .37 .42 .32 19.00 .61 3.9 .23 38 5.11 5.89 YEAR (WY) .61 .61 1993 .61 1993 .28 .27 .29 .25 .23 .21 .23 .25 .26 .32 .23 .23 .41 .24 .22 .19 .18 .27 1.8 .54 .28 .40 .27 .27 .22 .23 .22 .23 .32 .35 9.69 .32 1.8 .18 19 2.69 3.00 .32 .32 1993 .32 1993 WATER YEAR 34 43 0 Dec 12 Aug IS Aug May 11 May 59 78 80 28 18 30 29 24 1 1 .23 .33 .63 .25 .21 .29 1.2 .55 .32 .34 4.0 .57 .48 .41 .94 .50 .34 .31 .29 .25 .26 .96 1.9 .57 .42 .48 .39 .27 .25 .24 .25 18.43 .59 4.0 .21 37 4.95 5.71 .89 1.18 1992 .59 1993 WATER . . . 6. . . 64 10. 312 3. 48. . . . .23 .23 .22 .22 .22 .19 .18 .19 .20 .18 .20 .18 .16 .17 .22 .31 .15 .20 .18 .14 .13 .23 .28 .17 .14 .13 .13 .14 .12 .24 .18 5.86 .19 .31 .12 12 1.58 1.82 .37 .56 1992 .19 1993 YEARS 1992 43 43 43 1 Jul 12 Aug IS Aug May 11 May 59 81 96 30 19 .26 .22 .14 .13 .72 .20 .40 .99 .27 .33 .18 .18 .26 .16 1.1 1.1 .27 .19 .14 .13 .15 .14 .26 .27 .17 .14 .39 .34 .23 .63 10.09 .34 1.1 .13 20 2.80 3.13 .36 .38 1992 .34 1993 - 1993 1993 1993 16 1992 29 1993 24 1993 1 1993 1 1993 e Estimated RIO BLANCO BASIN 50075000 RIO ICACOS NEAR NAGUABO, PR 325 LOCATION.—Lat 18«16'38", long 65«47'09", Hydrologic Unit 21010005, in Caribbean National Forest, off Highway 191, at El 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 a (3.26 km2 ). 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 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEE MAR APR MAY JUN JUL AUG SEP 1 6.7 4.7 2 5.5 9.9 3 5.0 23 4 5.4 79 5 5.2 9.1 6 8.5 14 7 5.3 7.7 8 5.0 7.6 9 5.6 8.1 10 4.7 35 11 .5 5.8 12 .4 12 13 .3 6.6 14 .2 9.5 15 .5 9.2 16 .1 30 17 .1 14 18 3.8 44 19 3.6 12 20 3.9 23 21 3.2 22 22 14 68 23 4.2 12 24 3.4 17 25 3.4 16 26 3.3 9.8 27 3.2 36 28 3.1 30 29 3.1 60 30 3.3 25 31 5.8 TOTAL 148.3 660.0 MEAN 4.78 22.0 MAX 14 79 MIN 3.1 4.7 AC-FT 294 1310 CFSM 3.80 17.5 IN. 4.38 19.49 STATISTICS OF MONTHLY MEAN MEAN 15.8 18 . 7 MAX 32.1 46.8 (WY) 1986 1951 MIN 4.78 8.00 (WY) 1993 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 ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 12 11 12 24 13 34 11 9.9 9.5 9.3 9.4 9.4 9.5 10 10 9.1 9.4 9.6 9.3 9.5 9.4 25 10 21 23 81 21 24 104 47 28 634.3 20.5 104 9.1 1260 16.2 18.73 20 17 18 14 34 27 26 15 14 13 14 13 15 14 12 15 12 11 12 11 11 58 15 13 24 12 15 46 33 13 12 579 18.7 58 11 1150 14.8 17.09 DATA FOR WATER 15.6 31.3 1988 4.99 1990 FOR 12.9 26.9 1952 7.72 1987 11 12 12 11 11 11 10 10 10 9.8 9.8 15 10 9.7 9.4 9.3 9.5 9.6 9.3 55 30 12 10 8.2 7.9 8.1 8.3 7.7 —— 346.6 12.4 55 7.7 687 9.82 10.23 YEARS 1945 13.4 44.0 1950 4.86 1983 7.4 7.8 7.1 6.9 6.9 6.9 7.2 7.7 6.9 6.9 6.9 6.9 7.2 6.7 7.6 26 13 9.8 9.8 11 8.6 7.9 21 18 9.4 13 8.2 8.0 7.0 6.8 6.2 290.7 9.38 26 6.2 577 7.44 8.58 - 1993 10.7 26.1 1949 3.90 1951 1992 CALENDAR YEAR 4904. 13. 161 3. 3. 9730 10. 144. 26 8. 4. 5 4 1 3 6 80 4 3 May 6 Oct 28 Oct 24 5.8 5.6 12 6.5 6.2 6.1 6.0 6.3 6.9 6.3 6.0 6.0 6.1 6.0 5.6 5.6 5.6 5.9 7.8 16 6.2 4.8 5.4 5.6 5.7 7.1 7.7 11 12 68—— 271.8 9.06 68 4.8 539 7.19 8.02 58 54 23 8.1 7.8 6.8 6.0 15 31 10 11 8.8 8.9 24 9.5 8.0 8.1 7.5 7.1 7.6 6.4 6.1 e6.8 7.0 29 13 52 11 8.4 11 7.0 477.9 15.4 58 6.0 948 12.2 14.11 7.4 7.3 7.3 6.3 6.0 5.7 6.5 6.2 6.6 9.6 6.5 5.7 13 6.7 6.3 5.5 4.6 6.9 45 14 5.5 10 4.4 4.5 3.5 3.8 3.7 3.2 5.6 6.6 233.9 7.80 45 3.2 464 6.19 6.91 3.3 5.3 14 3.6 3.1 4.5 26 10 3.3 3.5 60 8.2 5.0 4.5 25 9.1 4.4 4.3 4.5 4.8 5.3 28 46 15 7.2 9.8 8.0 5.4 5.0 e4.7 e4.5 345.3 11.1 60 3.1 685 8.84 10.19 e7.0 e6.0 e6.0 eS.6 5.6 5.0 5.0 5.0 4.8 4.7 5.1 4.6 e4.8 e4.4 e4.7 e8.0 ell eS.O e7.4 5.1 4.8 8.7 8.8 4.6 4.7 4.7 5.2 5.7 4.8 9.9 6.5 183.2 5.91 11 4.4 363 4.69 5.41 6.9 5.4 4.7 4.9 19 14 18 27 7.1 11 5.6 5.2 6.4 4.8 32 57 12 8.6 6.9 6.8 6.7 5.4 7.8 6.0 4.4 3.9 13 9.4 5.6 15 340.5 11.3 57 3.9 675 9.01 10.05 , BY WATER YEAR (WY) 12.8 34.4 1950 4.77 1984 FOR 1993 4511 12 104 3 3 567 5 8950 9 133 25 8 4 17.5 26.3 1948 10.7 1951 WATER YEAR .5 .4 Dec 29 .1 Oct 28 .3 Oct 24 Dec 29 .01 Dec 29 .81 .20 .0 .5 12.3 20.5 1987 5.19 1985 13.9 38.8 1952 7.35 1991 14.4 24.5 1945 5.91 1993 WATER YEARS 1945 14.6 21.0 11.2 470 1.5 2.0 2860 8.96 10550 11.6 157.08 29 8.2 4.7 Sep Mar Apr Apr Apr 16.9 37.6 1989 7.03 1986 - 1993 1952 1984 18 1989 22 1946 7 1946 21 1983 21 1983 e Estimated 326 THIS PAGE WAS LEFT BLANK INTENTIONALLY 01 234 MILES V. /--< v , V. ,A owrictnrjf . If. •iX'S / 4\WS§kV^( ' S EXPLANATION A 0920 SURFACE-WATER STATION AND NUMBER QUALITY-OF-WATER STATION AND NUMBER 96 WELL AND WELL NUMBER Figure 22.-Southeastern river basins the Rio Humacao to Rio Seco basins. CO i\> N 328 RIO HDMACAO BASIN 50081000 RIO HOMACAO AT LAS PIBDRAS, PR LOCATION.—Lat 18°10'27", long 6S°S2'11" / 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 3 (17.22 km3 ). 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 and crest-stage gage. 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 ft'/s (28.3 m'/s) and estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN AUG SEP 1 16 12 2 15 11 3 14 13 4 14 31 5 14 16 6 14 33 7 13 20 8 13 15 9 13 13 10 12 13 11 12 12 12 12 12 13 12 24 14 12 13 15 11 19 16 13 18 17 13 19 18 12 26 19 13 27 20 12 20 21 12 17 22 14 20 23 12 16 24 11 15 25 14 14 26 12 13 27 11 21 28 11 48 29 14 40 30 13 224 31 14 TOTAL 398 795 MEAN 12.8 26.5 MAX 16 224 MIN 11 11 AC-FT 789 1580 CFSM 1.93 3.98 IN. 2.23 4.45 STATISTICS OF MONTHLY MEAN MEAN 32.8 42.6 MAX 74.9 126 (WY) 1975 1988 MIN 12 . 8 17 . 0 (WY) 1993 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 30 24 22 26 22 21 18 17 17 16 16 16 15 15 15 14 14 15 14 14 15 15 14 16 16 41 20 17 47 42 32 636 20.5 47 14 1260 3.09 3.56 32 28 24 21 20 21 24 22 25 20 19 19 19 20 17 19 17 18 16 16 16 18 18 15 31 18 18 19 23 18 16 627 20.2 32 15 1240 3.04 3.51 15 20 20 14 14 13 13 13 13 13 15 14 14 12 12 11 11 11 11 12 12 11 12 12 10 10 10 10 —— —— —— 358 12.8 20 10 710 1.92 2.00 DATA FOR WATER YEARS 1974 34.6 112 1988 11.5 1992 FOR 19.9 34.1 1992 10.8 1990 14.8 20.5 1988 11.0 1977 10 11 9.0 9.0 9.0 8.7 8.7 8.3 8.4 8.4 elO ell elO ell e9.6 e!2 ell e!5 e!4 elO e8.0 e7.0 e6.6 7.0 7.0 7.9 6.9 6.8 7.3 6.6 6.8 282.0 9.10 15 6.6 559 1.37 1.58 - 1993 11.4 16.4 1989 9.10 1993 1992 CALENDAR YEAR 8341.5 22.8 466 6.9 7.3 16550 3.43 46.66 31 15 8.5 May 26 May 22 Apr 25 6.8 6.5 6.6 6.3 6.2 7.4 5.7 6.1 6.3 6.7 5.5 5.2 13 8.6 7.6 7.6 7.3 6.9 21 11 9.7 7.8 9.3 8.2 7.9 11 11 11 20 15 ___ 269.2 8.97 21 5.2 534 1.35 1.51 11 17 10 9.5 11 10 8.6 15 135 28 14 11 10 16 12 9.6 9.8 10 8.9 9.2 8.9 8.7 7.6 9.4 9.2 8.6 16 17 9.4 8.3 7.7 476.4 15.4 135 7.6 945 2.31 2.66 8.0 7.4 7.1 7.0 6.8 6.4 6.9 9.6 13 14 11 8.3 9.6 10 14 11 8.2 8.7 239 76 21 16 14 14 12 10 9.4 9.4 9.4 12 609.2 20.3 239 6.4 1210 3.05 3.41 10 11 21 12 10 9.5 9.2 14 9.6 8.0 335 41 20 16 13 14 12 9.3 8.4 8.4 8.8 e204 171 44 28 e34 e26 21 19 17 17 1181.2 38.1 335 8.0 2340 5.73 6.61 17 16 16 15 15 15 14 14 15 15 14 14 13 12 13 29 16 14 13 13 12 13 18 19 16 14 13 13 12 12 19 464 15.0 29 12 920 2.25 2.60 17 18 30 14 28 16 12 16 15 62 29 17 15 15 16 21 14 13 12 20 12 12 17 18 29 18 13 15 16 186 —— 736 24.5 186 12 1460 3.69 4.12 , BY WATER YEAR (WY) 9.24 13.1 1976 5.88 1977 FOR 1993 6832 18 335 5 6 1910 6 4 13550 2 38 24 14 8 15.3 42.2 1992 7.26 1990 WATER YEAR .0 .7 Jul 11 .2 Apr 12 .1 Apr 6 Nov 30 .13 Nov 30 .8 Apr 13 .81 .22 .0 15.9 29.0 1992 5.91 1977 19.8 38.1 1993 7.95 1990 WATER 22. 37. 12. 1670 2. 2. 20800 34. 16200 3. 45. 33 14 6. 19.3 32.7 1977 9.45 1974 YEARS 1974 - 4 6 1 Nov 27 2 Jul 15 8 Jul 19 Sep 6 40 Sep 6 36 68 8 30.7 54.1 1975 10.0 1990 1993 1988 1990 1987 1974 1974 1960 1960 e Estimated 329 RIO HUMACAO BASIN 50082000 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 m) downstream from Quebrada Mariana, and 0.4 ml (0.6 km) south of Humacao. DRAINAGE AREA.--17.3 ml' (44.8 km"). PERIOD OP RECORD.--Hater years 1958-66, 1969 to current year. HATER-QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 16... DEC 17... FBB 1993 12. .. APR 26... MAY 26... AUG 10... TIME 1145 1100 1245 1410 1310 1300 DIS- CHARGE, INST. CUBIC FEET PER SECOND 12 6.4 7.5 13 4.3 17 SPE- CIFIC CON- DUCT- ANCE (US/CM) 498 317 313 264 329 301 PH HATER WHOLE FIELD (STAND- ARD UNITS) 7.2 6.6 7.2 6.9 7.2 6.8 TEMPER- ATURE WATER (DBG C) 30.5 25.3 29.0 31.0 28.0 32.0 TUR- BID- ITY (NTU) 6.2 1.8 11 7.1 4.5 2.9 OXYGEN, DIS- SOLVED (MG/L) 4.8 6.1 7.4 6.7 6.1 4.3 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 63 80 96 88 78 56 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 35 <10 23 <10 42 15 COLI- PORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 40000 K600000 600000 23000 21000 33000 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 9300 540000 80000 39000 3800 4500 DATE OCT 1992 16... DEC 17... PBB 1993 12... APR 26. .. MAY 26... AUG 10... HARD- NESS TOTAL (HG/L AS CAC03) HARD- NESS NONCARB WH HAT TOT FLD MG/L AS CAC03 CALCIUM DIS- SOLVED (HG/L AS CA) MAGNE- SIUM, DIS- SOLVED (HG/L AS MG) SODIUM, DIS- SOLVED (HG/L AS NA) 53 0 14 4.2 18 94 5 26 7.1 29 85 2 23 6.6 26 ALKA- SODIUM POTAS- LINITY CHLO- AD- SIUH, WAT WH SULFATB RIDE, SORP- DIS- TOT PET SULPIDB DIS- DIS- TION SOLVED FIELD TOTAL SOLVED SOLVED RATIO (HG/L HG/L AS (HG/L (MG/L (HG/L AS K) 2.4 1 2.1 1 2.3 CAC03 84 70 80 93 89 120 AS S) AS S04) AS CL) <0.5 12 19 <0.5 13 32 9.6 27 SOLIDS, DATE OCT 1992 16... DEC 17... FBB 1993 12.. . APR 26.. . MAY 26.. . AUG 10.. . FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.10 -- -- 0.10 -- 0.10 SILICA, DIS- SOLVED (HG/L AS SI02) 32 -- -- 39 -- 39 SUM OP CONSTI- TUENTS, DIS- SOLVED (MG/L) 210 -- -- 204 -- 206 RESIDUE DLIDS, TOTAL 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 FENDED (HG/L (MG/L (HG/L (MG/L (HG/L DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) 12 22 19 11 24 11 0 0 0 0 0 0 .740 .870 .760 .680 .930 .980 0. 0. 0. 0. 0. 0. 030 030 040 020 070 020 0 0 0 0 1 1 .770 .900 .800 .700 .00 .00 0. 0. 1. 0. 0. 0. 250 730 30 310 620 250 0. 0. 0. 0. 0. 0. 53 47 40 29 48 15 K = non-ideal count 330 RIO HDMACAO BASIN 50082000 RIO HUMACAO AT HIGHWAY 3 AT HUMACAO, PR—Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 16... DEC 17.. . FBB 1993 12... APR 26... MAY 26... AUQ 10... DATE OCT 1992 16... DEC 17... FBB 1993 12... APR 26.. . MAY 26... AUG 10... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.88 1.2 1.7 0.60 1.1 0.40 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) 4700 -- -- 570 -- -- NITRO- GEN, TOTAL (MG/L AS N) 1.4 2.1 2.5 1.3 2.7 1.4 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) 4 -- -- <1 -- -- NITRO- GEN, TOTAL (MG/L AS N03) 6.1 9.3 11 5.8 11 6.2 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) 280 -- -- 140 -- -- PHOS- PHORUS ARSENIC TOTAL TOTAL (MG/L (UG/L AS P) AS AS) 0.220 4 0.320 0.290 0.160 <1 0.580 0.150 MERCURY TOTAL SBLB- RECOV- NIUM, ERABLB TOTAL (UG/L (UG/L AS HG) AS SB) <0.10 <1 __ __ <0.10 <1 __ __ BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 -- -- <100 -- - — SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) <1 __ -- <1 -- -- BORON, TOTAL RECOV- ERABLE (UG/L AS B) 20 -- -- 40 -- " ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) 60 -- -- 10 -- -- CHRO- CADMIUM MIOM, TOTAL TOTAL RECOV- RECOV- ERABLE ERABLB (UG/L (UG/L AS CD) AS CR) 4 7 __ __ <1 <1 __ .. CYANIDE TOTAL PHENOLS (MG/L TOTAL AS CN) (UG/L) <0.010 2 __ __ <0.010 <1 __ __ COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) 11 — -- <10 -- " MBTHY- LENE BLUB ACTIVE SUB- STANCE (MG/L) 0.08 -- -- 0.07 -- -- RIO GOAYANES BASIN 50083500 RIO OOAYANES AT YABOCOA, PR WATER-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> (44.6 km 1 ). PERIOD OF RECORD.—Hater years 1958-62, 1968-70, 1980 to current year. HATER-QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 331 Yabucoa DATE OCT 1992 19... DEC 17... PEB 1993 12... MAY 03... JUN 07... AOG 11... TIME 1150 0945 1420 1200 1315 1430 DIS- CHARGE, INST. CUBIC FEET PER SECOND 17 17 50 24 20 18 SPE- CIFIC CON- DUCT- ANCE (US/CM) 175 190 111 200 209 150 PH HATER WHOLE FIELD (STAND- ARD UNITS) 7.4 7.6 7.2 7.1 7.2 6.6 TEMPER- ATURE HATER (DBG C) 26.5 21.8 24.5 24.0 27.5 27.5 TUR- BID- ITY (NTU) 3.6 4.8 76 73 5.5 52 OXYGEN, DIS- SOLVED (MG/L) 6.7 7.7 6.8 7.6 7.4 5.8 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 81 94 78 90 88 61 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) <10 <10 29 29 <10 20 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 530 760 K60000 500 5200 60000 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 200 210 K53000 390 4100 9700 DATE OCT 1992 19... DEC 17... PEB 1993 12... MAY 03. .. JUN 07. .. AUG 11. .. HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH HAT DIS- (MG/L TOT FLD SOLVED AS MG/L AS (MG/L MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) SODIUM AD- SORP- TION RATIO 34 1 8.7 3.1 11 44 0 11 3.9 14 ALKA- POTAS- LINITY SIUM, HAT WH DIS- TOT FBT SULFIDB SOLVED FIELD TOTAL (MG/L MG/L AS (MG/L AS K) 29 0 2.8 0.6 4.3 0.7 1.5 0.8 2.2 0.9 1.6 CAC03 64 61 52 28 56 46 <0.5 <0.5 CHLO- SULFATB RIDE, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS S) AS SO4) AS CL) 4.2 10 4.6 12 3.6 12 SOLIDS, RESIDUE DATE OCT 1992 19.. . DEC 17... FEB 1993 12... MAY 03.. . JUN 07... AUG 11.. . FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.10 -- -- 0.10 -- 0.10 SILICA, DIS- SOLVED (MG/L AS SIO2) 16 -- -- 27 — 33 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 49 -- -- 85 -- 107 SOLIDS, DIS- SOLVED (TONS PER DAY) 2.25 -- -- 5.56 -- 5.20 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 6 88 182 384 4 126 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.310 0.190 0.390 0.290 0.190 0.370 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.010 0.010 0.010 0.010 0.010 0.030 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 0.320 0.200 0.400 0.300 0.200 0.400 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.050 0.020 0.020 0.040 0.050 0.080 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.15 0.48 1.2 0.40 0.35 0.30 non-ideal count 332 DATE OCT 1992 19.. . DEC 17.. . FEB 1993 12... MAY 03... JUN 07... AUG 11... RIO GDAYANBS BASIN 50083500 RIO GUAYANBS AT YABUCOA, PR—Continued HATER-QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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 AS N) 0.20 0.50 1.4 0.44 <0.20 0.30 AS N) AS N03) AS P) AS AS) AS BA) AS B) 2.3 1.1 1.2 0.40 0.30 4.0 3.4 3.5 3.1 0.050 0.060 0.320 0.070 0.040 0.050 300 <100 CHRO- BORON, CADMIUM MIUM, COPPER, TOTAL TOTAL TOTAL TOTAL RBCOV- RECOV- RBCOV- RECOV- BRABLB BRABLE BRABLB BRABLE (DG/L (DG/L (DG/L (UG/L <10 30 AS CO) AS CR) AS CO) 20 130 10 DATE OCT 1992 19... DEC 17... FBB 1993 12.. . MAY 03.. . JUN 07... AUG 11... 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) METHY- LENE BLUB ACTIVE SUB- STANCE (MG/L) 4600 3300 12 1100 130 0.40 <0.10 <1 <1 <0.010 •cO.010 0.03 0.02 PESTICIDE ANALYSES DATE JUN 1993 18... TIME 1135 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 <0.010 DI- AZINON, TOTAL (UG/L) DI- ENDO- BLDRIN SULFAN, TOTAL TOTAL (UG/L) (UG/L) <0.01 <0.010 <0.010 DATE JUN 1993 18.. . BNDRIN HATER UNFLTRD BTHION, RBC 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 (UG/L) <0.01 METHYL PARA- THION, TOTAL (UG/L) <0.01 MIREX, TOTAL (UG/L) <0.01 DATE JUN 1993 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, 2,4,5-T 2, 4-DP SILVEX, TOTAL TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) (UG/L) <0.01 <0.01 <0.01 <0.01 RIO QUAYANES BASIN 50086500 RIO GUAYANBS ABOVE MOUTH AT PLAYA DE GDAYANBS, PR WATER-QOALITY RECORDS LOCATION.--Lat 18°03'45", long 65°49'42", at old railroad crossing, 0.2 mi (0.3 km) from west of Playa de Guayanes, and 3.5 mi (5.6 km) northeast of Yabucoa plaza. DRAINAGE AREA.--34.0 mi a (88.1 km'). PERIOD OF RECORD.--Hater years 1974 to current year. WATER-QOALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 333 auth, 0.4 mi (0.6 km) DATE OCT 1992 19... DEC 23... MAR 1993 03... APR 26... MAY 26. .. AUG 10... TIME 1350 1030 1245 1200 1220 1110 DIS- CHARGE, INST. CUBIC FEET PER SECOND 44 59 71 54 64 48 SPE- CIFIC CON- DUCT- ANCE (US/CM) 186 168 210 185 168 185 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.6 7.6 7.6 7.3 7.1 7.0 TEMPER- ATURE WATER (DBG C) 28.5 25.6 25.0 31.0 24.0 30.5 TUR- BID- ITY (NTU) 22 14 18 11 62 12 OXYGEN, DIS- SOLVED (MG/L) 7.8 6.3 7.1 7.7 7.6 4.9 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 100 84 90 100 98 59 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 40 11 53 <10 24 <10 COLI- FORM, FECAL, 0.45 UM-MF (COLS. / 100 ML) 350 1200 370 280 K17000 550 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) K13 450 280 320 7000 260 DATE OCT 1992 19... DEC 23... MAR 1993 03. .. APR 26... MAY 26. .. AUG 10... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MG/L TOT FLD SOLVED AS MG/L AS (MG/L CAC03) CACO3 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS NA) 48 0 12 4.7 11 51 0 13 4.6 19 66 1 17 5.7 22 SODIUM AD- SORP- TION RATIO 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) 2 3.2 1 1.7 1 2.6 CACO3 62 62 67 64 62 72 AS S) AS S04) AS CL) <0.5 8.7 13 <O.S 5.0 15 6.9 22 DATE OCT 1992 19... DEC 23... MAR 1993 03.. . APR 26... MAY 26... AUG 10... FLUO- RIDE, DIS- SOLVED (MG/L AS F) <0.10 -- -- <0.10 -- 0.10 SILICA, DIS- SOLVED (MG/L AS SI02) 35 -- -- 38 -- 37 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 136 -- -- 135 -- 156 SOLIDS, DIS- SOLVED (TONS PER DAY) 16.2 -- — 19.8 -- 20.2 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 24 12 36 8 81 27 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.390 0.490 0.390 0.290 0.390 0.380 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.010 0.010 0.010 0.010 0.010 0.020 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 0.400 0.500 0.400 0.300 0.400 0.400 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.960 0.160 0.110 0.030 0.080 0.02 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.94 1.9 1.1 0.47 0.72 0.58 K = non-ideal count 334 DATE OCT 1992 19.. . DEC 23... MAR 1993 03.. . APR 26.. . MAY 26... AUG 10.. . DATE OCT 1992 19.. . DEC 23... MAR 1993 03... APR 26. . . MAY 26... AUG 10... RIO GUAYANBS BASIN 50086500 RIO GUAYANBS ABOVE MOUTH AT PLAYA DE GUAYANBS, PR—Continued HATER-QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 1.9 2.1 1.2 0.50 0.80 0.60 IRON, TOTAL RECOV- ERABLE (UG/L AS FE) NITRO- GEN, TOTAL (MG/L AS N) 2.3 2.6 1.6 0.8 1.2 1.0 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS NO3) 10 16 12 7.1 3.5 4.4 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.060 0.090 0.040 0.040 0.060 0.120 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 -- — 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 — — METHY- LENB BLUE ACTIVE SUB- STANCE (MG/L) 2200 1100 130 120 <0.10 <0.10 <0.010 <0.010 0.01 0.02 RIO MAUNABO BASIN 50090500 RIO MAUNABO AT LIZAS, PR 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 Maunabo. 335 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.—Hater-stage recorder and crest-stage gage. Elevation of gage is 230 ft (70 m), from topographic map. REMARKS.--Records fair except those for estimated daily discharges and July 18 to Sept. 30, which are poor. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR HAY JDN JUL AUG SEP 1 9.4 9.0 2 8.7 8.4 3 8.1 17 4 7.7 106 5 7.2 17 6 7.1 42 7 6.9 43 8 6.6 17 9 6.4 14 10 6.5 16 11 6.1 12 12 5.8 11 13 5.8 10 14 5.5 13 15 5.6 10 16 7.4 12 17 6.4 13 18 5.3 86 19 6.6 28 20 8.0 58 21 96 18 22 36 26 23 12 17 24 25 42 25 18 17 26 12 14 27 9.0 18 28 7.9 32 29 13 18 30 8.7 29 31 20 TOTAL 394.7 773.4 MEAN 12.7 25.8 MAX 96 106 MIN 5.3 8.4 AC-FT 783 1530 CFSM 2.37 4.79 IN. 2.73 5.35 20 16 42 24 17 15 13 12 11 11 10 10 10 9.5 9.0 8.6 8.4 8.3 8.2 8.1 7.9 7.6 7.6 8.6 10 42 14 10 13 25 12 428.8 13.8 42 7.6 851 2.57 2.96 STATISTICS OF MONTHLY MEAN DATA MEAN 28.2 32.4 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 FLOW INSTANTANEOUS PEAK STAGE ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 18.1 35.2 1978 8.87 1981 FOR 23 17 13 13 14 24 19 13 12 12 13 13 11 11 10 10 10 10 11 10 9.5 16 14 11 18 11 15 19 56 18 15 471.5 15.2 56 9.5 935 2.83 3.26 14 13 12 12 11 11 11 11 10 9.9 10 21 13 11 10 9.9 9.9 9.6 9.2 9.1 8.7 8.4 8.6 8.4 8.0 7.9 7.7 7.6 ___ ___ 292.9 10.5 21 7.6 581 1.94 2.03 FOR WATER YEARS 1971 12.9 27.1 1992 7.79 1981 11.0 24.5 1982 6.10 1979 7.7 7.8 7.4 7.3 7.3 7.1 6.9 7.1 7.2 7.0 7.2 6.8 7.7 6.9 6.6 6.4 6.6 6.6 8.8 16 7.9 6.6 7.3 6.3 6.3 6.7 6.1 5.9 5.7 5.9 5.6 222.7 7.18 16 5.6 442 1.34 1.54 - 1993 9.55 18.9 1976 4.32 1979 1992 CALENDAR YEAR 6441.6 17.6 290 3.6 4.2 12780 3.27 44.54 29 11 5.1 Sep 20 May 4 Apr 4 5.5 6.0 7.0 5.8 5.4 5.5 5.0 5.0 5.0 4.8 5.0 6.0 9.2 11 6.4 5.4 5.0 4.7 6.3 4.4 .3 .4 .1 .8 .6 .6 .6 .4 .3 5.7 165.2 5.51 11 4.3 328 1.02 1.14 9.1 8.6 8.0 .8 .4 .9 .1 .2 25 10 5.9 4.8 4.8 96 10 6.6 6.4 7.4 5.2 6.6 5.5 5.0 5.3 11 11 24 62 16 8.2 6.4 5.3 396.5 12.8 96 4.1 786 2.38 2.74 4.9 4.9 4.4 4.1 3.8 3.5 3.8 6.3 4.2 9.3 5.0 4.1 7.3 21 18 18 13 42 200 62 12 11 7.4 6.5 5.7 5.2 5.0 4.7 5.3 6.2 508.6 17.0 200 3.5 1010 3.15 3.52 6.1 17 40 9.8 6.9 6.2 9.2 8.5 6.0 5.5 577 36 20 19 28 40 19 21 19 19 19 62 77 44 28 21 20 16 16 15 16 1247.2 40.2 577 5.5 2470 7.48 8.62 16 16 16 14 12 11 11 12 11 14 11 12 14 15 16 37 12 10 10 10 9.8 9.7 25 26 11 10 11 10 10 12 14 428.5 13.8 37 9.7 850 2.57 2.96 11 11 11 12 25 13 13 22 21 28 16 13 13 12 11 12 11 11 9.9 9.6 11 11 11 10 12 11 10 12 e98 e37--- 508.5 16.9 98 9.6 1010 3.15 3.52 , BY WATER YEAR (WY) 7.12 10.8 1976 3.92 1979 FOR 1993 5838. 16. 577 3. 4. 2680 10. 11580 2. 40. 25 10 5. 13.5 25.1 1979 5.13 1974 WATER YEAR 5 0 Jul 11 5 Jun 6 2 Jun 1 Jul 11 65 Jul 11 97 37 1 17.8 47.1 1979 4.40 1974 18.4 40.2 1993 3.70 1974 WATER 18 36 12 2480 2 2 6780 14 13290 3 46 33 11 5 24.2 131 1979 6.18 1974 YEARS 1971 .3 .7 .1 Aug .2 Jul .8 Jul Nov . 84 Nov .41 .32 .1 25.3 81.5 1979 7.99 1980 - 1993 1979 1977 31 1979 16 1974 11 1974 25 1977 25 1977 e Estimated RIO MAUNABO BASIN 50091000 RIO MAOKABO AT MAUNABO, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°00'24", long 65°54'19", at bridge on Highway 3, 0.4 mi (0.6 km) southwest of Maunabo plaza, and 1.3 mi (2.1 km) upstream from mouth. DRAINAGE AREA.--12.4 mi* (32.1 km1 ). PERIOD OF RECORD.--Water years 1958-66, 1975 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 20... DEC 21. .. MAR 1993 03... APR 28... JUN 07... AUG 11... TIME 1250 1235 1040 1345 1200 1240 DIS- CHARGE, INST. CUBIC FEET PER SECOND 7.1 9.3 6.7 8.7 9.4 7.2 SPE- CIFIC CON- DUCT- ANCE (US/CM) 255 265 272 257 253 237 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.3 7.7 7.5 7.2 7.1 7.2 TEMPER- ATURE HATER (DBG C) 29.5 25.9 25.5 33.0 29.0 29.5 TUR- BID- ITY (NTU) 4.6 2.6 5.3 2.8 2.8 17 OXYGEN, DIS- SOLVED (MG/L) 6.3 7.0 8.0 8.1 7.5 5.4 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 83 88 102 106 90 78 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) <10 32 <10 <10 <10 12 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 2100 450 570 3300 3300 40000 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 300 380 330 K140 490 6700 DATE OCT 1992 20... DEC 21... MAR 1993 03... APR 28. .. JUN 07. .. AUG 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) CAC03 AS CA) AS MG) AS NA) 82 1 20 7.7 22 85 0 21 7.8 25 73 1 18 6.8 19 ALKA- POTAS- LINITY CHLO- SIUM, HAT 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) 1.5 1.7 1.5 CACO3 AS S) AS S04) AS CL) 82 <0.5 10 19 87 90 74 0.6 9.8 21 84 71 -- 10 20 SOLIDS, RESIDUE DATE OCT 1992 20... DEC 21... MAR 1993 03... APR 28.. . JUN 07... AUG 11... FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.20 -- -- 0.10 -- 0.10 SILICA, DIS- SOLVED (MG/L AS SIO2) 40 — -- 40 -- 36 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 170 -- -- 179 -- 154 SOLIDS, DIS- SOLVED (TONS PER DAY) 3.24 -- -- 4.19 -- 3.0 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 3 2 10 7 5 19 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.390 0.390 0.190 0.090 0.690 0.190 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.010 0.010 0.010 0.010 0.010 0.010 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 0.400 0.400 0.200 0.100 0.700 0.200 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.060 0.020 0.030 0.030 0.070 0.010 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.54 0.68 0.37 0.57 0.13 0.39 K = non-ideal count RIO MAUNABO BASIN 50091000 RIO MAUNABO AT MAUNABO, PR- -Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 337 DATE OCT 1992 20.. . DEC 21... MAR 1993 03... APR 28... JUN 07... AUG 11... DATE OCT 1992 20.. . DEC 21... MAR 1993 03... APR 28... JUN 07... AUG 11.. . NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.60 0.70 0.40 0.60 0.40 0.70 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) 180 -- -- 580 -- -- NITRO- GEN, TOTAL (MG/L AS N) 1.0 1.1 0.60 0.70 0.40 0.60 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) <1 -- -- 1 -- -- NITRO- GEN, TOTAL (MG/L AS NO3) 4.4 4.9 2.7 3.1 4.8 2.7 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) 260 -- -- 50 -- -- PHOS- PHORUS TOTAL (MG/L AS P) 0.050 0.060 0.070 0.050 0.040 0.070 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) <0.10 — -- <0.10 -- -- BARIUM, TOTAL ARSENIC RBCOV- TOTAL BRABLE (UG/L (UG/L AS AS) AS BA) <1 <100 __ __ <1 <100 __ — — — — SILVER, SBLB- TOTAL NIUM, RBCOV- TOTAL BRABLE (UG/L (UG/L AS SB) AS AG) <1 1 __ __ <1 <1 __ __ BORON, TOTAL RECOV- ERABLE (UG/L AS B) 40 -- -- 40 -- — — ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) 60 -- -- <10 -- -- CHRO- CADHIUM HIUM, 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 7 — __ <0.010 <1 __ __ COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) 50 -- -- <10 -- " MBTHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 0.05 — -- 0.03 -- -- 336 RIO CHICO BASIN 50091800 RIO CHICO AT PROVIDENCIA, PR HATER-QUALITY RECORDS LOCATION.—Lat 17°59'16", long 66°00'18", at flat low bridge 200 ft (61 m) south of Highway above mouth, and 1.5 mi (2.4 km) southeast of Patillas plaza. DRAINAGE AREA.--4.9 mi> (12.8 km'). PERIOD OF RECORD.--Water years 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 3, 0.5 mi (0.8 km) DATE OCT 1992 20... DEC 18... FBB 1993 25... APR 28... MAY 28. .. AUG 11... DATE OCT 1992 20... DEC 18... FBB 1993 25. .. APR 28... MAY 28... AUG 11. .. DIS- PH CHARGE, SPB- WATER INST. CIFIC WHOLE CUBIC CON- FIELD TEMPER- FEET DUCT- (STAND- ATURB TIME PER ANCB ARD WATER SECOND (US/CM) UNITS) (DBG C) 1120 0.67 418 7.6 27.5 1135 2.2 382 7.5 24.2 1125 1.2 440 7.5 25.5 1145 1.5 510 6.3 32.5 1200 5.4 307 7.6 28.5 1130 4.3 344 6.9 28.5 HARD- HARD- NESS MAGNB- NBSS NONCARB CALCIUM SIUM, SODIUM, TOTAL WH WAT DIS- DIS- DIS- (MG/L TOT FLD SOLVED SOLVED SOLVED AS MG/L AS (MG/L (MG/L (MG/L CACO3) CACO3 AS CA) AS MG) AS NA) 95 1 22 11 31 __ _- 97 0 28 6.5 51 __ 100 1 25 10 36 OXYGEN, OXYGEN COLI- DIS- DEMAND, FORM, STREP- SOLVED CHEM- FECAL, TOCOCCI TOR- OXYGEN, (PER- ICAL 0.45 FECAL, BID- DIS- CENT (HIGH UM-MF (COLS. ITY SOLVED SATUR- LEVEL) (COLS./ PER (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) 2.2 7.3 92 <10 K1500 590 1.8 7.0 89 45 K1300 840 7.7 7.8 98 61 110 130 5.7 6.7 88 55 K190 K10 15 7.1 90 48 3500 4100 3.6 6.9 83 24 24000 370 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) CACO3 AS S) AS SO4) AS CL) 1 2.6 110 <0.5 16 27 120 130 2 8.9 34 <0.5 43 61 74 2 2.8 93 -- 19 28 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- RIDE, DIS- CONSTI- DIS- AT DIS- SOLVED TUENTS, SOLVED DBG 105 GEN, GEN, GEN, GEN, GEN, . C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC SOLVED (HG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL DATE (MG/L AS SOLVED PER FENDED (MG/L (MG/L (MG/L (MG/L (MG/L AS F) SI02) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) OCT 20 DEC 18 FBB 25 APR 28 MAY 28 AUG 11 1992 0.20 31 210 0.38 1993 0.10 24 243 1.02 0.20 30 207 2.40 <1 3.96 0.040 4.00 0.080 0.72 11 0.490 0.010 0.500 0.130 0.47 11 0.390 0.010 0.400 2.00 0.60 15 0.180 0.020 0.200 4.20 1.3 65 0.090 0.010 0.100 1.90 0.30 9 0.070 0.030 0.100 1.90 0.40 K = non-ideal count DATE OCT 1992 20... DEC 18.. . FBB 1993 25... APR 28... MAY 28... AUG 11.. . DATE OCT 1992 20... DEC 18... FBB 1993 25... APR 28.. . MAY 28... AUG 11... RIO CHICO BASIN 50091800 RIO CHICO AT PROVIDENCIA, PR—Continued WATER-QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 339 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.80 0.60 2.6 5.5 4.1 2.3 IRON, TOTAL RECOV- ERABLE (UG/L AS FE) NITRO- GEN, TOTAL (MG/L AS N) 4.8 1.1 2.1 2.9 0.60 0.70 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N03) 21 9.7 25 13 19 28 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 2.50 0.250 2.00 4.40 0.980 0.920 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) 200 -- — <100 — — SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) BORON, TOTAL RECOV- ERABLE (UG/L AS B) <10 -- -- 130 -- -- 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- LBNE BLUE ACTIVE SUB- STANCE (MG/L) 1300 230 48 440 50 <0.10 0.10 60 40 <0.010 0.030 10 0.40 0.25 340 RIO GRAKDE DE PATILLAS BASIN 50092000 RIO GRANDE DE PATILLAS NEAR PATILLAS, PR LOCATION.—Lat 18°02'04 > , long 660 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 1 (47.4 kma ). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—February 1959 to October 1965 (annual low-flow and occasional measurements only), January 1966 to current year. GAGE.—Hater-stage recorder and crest-stage gage. Elevation of gage is 235 ft (72 m), from topographic map. 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 FEB MAR APR MAY JUN JUL AUG SEP 1 59 13 2 149 13 3 67 13 4 44 14 5 37 20 6 34 22 7 31 281 8 31 618 9 47 311 10 38 174 11 33 101 12 32 74 13 28 59 14 26 46 15 27 39 16 24 38 17 25 31 18 20 25 19 18 22 20 17 21 21 e!7 23 22 e20 88 23 e21 52 24 e!6 257 25 e!5 106 26 14 60 27 15 224 28 15 181 29 15 117 30 16 77 31 14 TOTAL 965 3120 MEAN 31.1 104 MAX 149 618 KIN 14 13 AC-FT 1910 6190 CFSM 1.70 5.68 IN. 1.96 6.34 STATISTICS OF MONTHLY MEAN MEAN 107 98.3 MAX 593 393 (WY) 1971 1978 MIN 14.4 16.1 (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 LOW FLOW ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 65 65 71 95 60 49 43 39 35 32 29 32 28 e27 e25 26 24 22 21 28 36 22 20 19 19 18 18 18 17 25 38 1066 34.4 95 17 2110 1.88 2.17 DATA 54.3 152 1971 8.63 1968 FOR 34 23 19 17 e2100 e600 e!30 e88 e68 e70 e58 e49 e44 e41 e47 e38 e36 e33 e32 e32 e29 e28 e30 e30 e30 e30 e28 e28 e23 e23 e23 3861 125 2100 17 7660 6.81 7.85 e23 e21 e21 e24 e24 eSO e30 e27 e25 e28 e26 e26 e23 e30 e32 e27 e24 e26 e24 e24 e21 e24 e24 e26 e24 e32 e30 e27 e26 ... —— 769 26.5 50 21 1530 1.45 1.56 FOR WATER YEARS 1966 34.9 125 1992 14.0 1973 28.4 94.6 1982 7.09 1973 e!8 e21 e20 e24 e22 e25 e47 e44 e21 e20 e!9 el9 e!9 e!9 e22 e!6 e23 e27 e!9 e!9 e!8 el9 el4 el5 elS e!2 ell ell e9.6 e9.2 16 613.8 19.8 47 9.2 1220 1.08 1.25 - 1992 24.4 43.8 1972 6.74 1968 1991 CALENDAR YEAR 14021 38. 618 11 13 27810 2. 28. 66 21 14 4 Nov 8 Sep 1 Aug 8 10 50 22 14 12 11 11 10 15 13 12 11 12 116 37 106 23 9.2 7.4 68 94 90 21 11 9.7 9.6 9.7 9.5 9.0 8.8 8.5 8.5 ... 798.9 26.6 116 7.4 1580 1.46 1.62 8.3 22 8.6 6.7 6.1 29 32 12 9.5 9.8 11 9.8 9.3 33 49 235 58 35 30 27 25 24 316 382 300 609 166 87 60 124 60 2794.1 90.1 609 6.1 5540 4.93 5.68 121 57 56 172 73 101 63 75 62 198 134 372 322 180 116 116 113 79 64 56 267 91 70 57 48 43 40 35 32 31 3244 108 372 31 6430 5.91 6.59 29 28 26 26 36 26 24 31 27 24 52 e35 e26 e31 e29 e24 e62 e30 e37 e39 e41 e200 e37 e31 elOO e33 e28 e24 e20 e!9 e!9 1194 38.5 200 19 2370 2.10 2.43 e25 e27 e25 e27 e300 e88 e41 e35 e62 e41 e37 e31 e29 e90 e41 e39 e35 e31 e31 e33 e29 e27 e31 e33 e29 e33 e31 e37 e34 e34 e46 1432 46.2 300 25 2840 2.52 2.91 e44 e38 e56 e35 e31 e38 e34 e60 e!20 eSO 30 27 26 24 23 27 61 78 128 eSO e40 e35 e31 e29 e27 e25 e23 e23 e23 e25 ... 1261 42.0 128 23 2500 2.30 2.56 , BY WATER YEAR (WY) 22.6 43.4 1976 9.98 1968 FOR 1992 21118. 57. 2100 6. 8. 30900 41890 3. 42. 106 29 13 55.6 172 1969 10.3 1974 WATER YEAR 8 7 Jan 5 1 May 5 9 Apr 25 Jan 5 15 93 67.9 200 1979 13.1 1974 65.0 164 1979 14.1 1974 WATER 59. 117 27. 4780 4. 5. 30900 4. 42900 3. 43. 100 28 12 73.4 231 1979 23.0 1991 YEARS 1966 - 2 7 Sep 16 8 May 9 0 Apr 10 Jan 5 6 May 13 24 97 86.1 314 1979 12.1 1967 1992 1979 1990 1975 1968 1968 1992 1968 e Estimated RIO GRANDB DB PATILLAS BASIN 50092000 RIO GRANDB DB PATILLAS NEAR PATILLAS, PR—Continued DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES 341 DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUQ SEP 1 e38 24 2 e33 23 3 e32 24 4 e30 78 5 e34 39 6 e46 61 7 e30 59 8 e28 36 9 e27 32 10 e26 29 11 e29 27 12 e27 26 13 «24 26 14 24 25 15 24 28 16 24 29 17 25 30 18 25 47 19 26 48 20 45 106 21 31 53 22 34 63 23 28 47 24 35 63 25 52 36 26 34 29 27 27 80 28 25 130 29 27 71 30 26 129 31 26 TOTAL 942 1498 MEAN 30.4 49.9 MAX 52 130 MIN 24 23 AC-PT 1870 2970 CFSM 1.66 2.73 IN. 1.91 3.05 STATISTICS OF MONTHLY MEAN MEAN 104 96.5 MAX 593 393 (WY) 1971 1978 MIN 14.4 16.1 <HY) 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 101 65 94 54 41 36 31 28 27 25 22 21 25 23 21 19 19 18 18 17 17 18 17 18 17 43 24 19 27 27 25 957 30.9 101 17 1900 1.69 1.95 DATA 53.4 152 1971 8.63 1968 FOR 68 39 30 26 26 32 45 37 31 30 30 30 28 28 26 26 26 26 27 26 26 43 38 28 55 32 41 49 152 57 40 1198 38.6 152 26 2380 2.11 2.44 34 30 28 26 25 24 24 23 23 22 22 33 28 23 22 21 21 20 23 21 20 19 19 19 19 19 18 18 —— 644 23.0 34 18 1280 1.26 1.31 FOR WATER YEARS 1966 35.0 125 1992 14.0 1973 28.2 94.6 1982 7.09 1973 17 18 17 17 17 16 16 16 16 16 15 15 16 16 16 16 16 16 19 18 14 13 13 13 14 14 13 13 13 13 12 474 15.3 19 12 940 .84 .96 - 1993 24.1 43.8 1972 6.74 1968 1992 CALENDAR YEAR 19364.8 52.9 2100 6.1 8.9 384102.89 39.36 90 29 15 Jan 5 May 5 Apr 25 14 13 13 12 12 12 12 13 19 16 13 13 25 20 14 14 38 15 16 16 15 14 14 14 13 14 15 14 82 29 —— 544 18.1 82 12 1080 .99 1.11 , BY WATER 22.4 43.4 1976 9.98 1968 84 143 33 19 31 27 15 14 27 20 13 12 11 288 49 27 23 27 20 21 23 21 18 17 20 22 17 16 15 14 13 1100 35.5 288 11 2180 1.94 2.24 YEAR (WY) 54.8 172 1969 10.3 1974 15 18 17 14 12 12 12 13 12 20 18 14 14 37 141 43 19 125 605 256 56 149 35 42 22 17 15 13 13 22 --- 1801 60.0 605 12 3570 3.28 3.66 67.7 200 1979 13.1 1974 FOR 1993 WATER YEAR 17983 49.3 1700 11 12 17400 17.49 35670 2.69 36.56 84 27 14 Jul 11 May 13 Apr 2 Jul 11 Jul 11 12 17 47 26 23 24 29 31 20 17 e!700 e200 ellO e90 e78 e340 e84 e68 e84 elOS e96 e261 e287 e337 elSO elOS e94 e76 e67 e61 e58 4700 152 1700 12 9320 8.28 9.55 68.1 164 1979 14.1 1974 WATER 58. 117 27. 4780 4. 5. 30900 4. 426403. 43. 100 28 12 e54 e48 e43 e39 e38 e36 e34 e34 e32 e36 e66 e36 e32 e30 e40 e540 e90 e54 e45 e40 e36 e90 e250 e!20 e58 e43 e41 e41 e36 e34 e58 2174 70.1 540 30 4310 3.83 4.42 73.2 231 1979 23.0 1991 YEARS 1966 - 9 7 Sep 16 8 May 9 0 Apr 10 Jan 5 6 May 13 22 70 e42 eSO eSO e32 e31 e27 e27 e45 e43 ellO e44 e32 e31 e27 e25 e84 e32 elOO e30 e72 e29 e32 e580 e70 e36 e29 e26 e34 e74 e!07 1951 65.0 580 25 3870 3.55 3.97 85.4 314 1979 12.1 1967 1993 1979 1990 1975 1968 1968 1992 1968 e Estimated 342 RIO GRANDS DB PATILLAS BASIN 50092000 RIO GRANDS DB PATILLAS NEAR PATILLAS, PR (National stream-quality accounting network station) WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1960 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 13... JAN 1993 14. .. APR 06... JUL 23... DATS OCT 1992 13... JAN 1993 14. . . APR 06... JUL 23. .. DATE OCT 1992 13. .. JAN 1993 14. .. APR 06. .. JUL 23... DATE OCT 1992 13. .. JAN 1993 14. .. APR 06... JUL 23. .. TIME 094S 092S 0930 1000 HARD- NESS NONCARB WH WAT TOT PLD MQ/L AS CAC03 1 0 2 1 SOLIDS, RESIDUE AT 180 DBG. C DIS- SOLVED (MG/L) 115 95 113 105 ALUM- INUM, DIS- SOLVED (UG/L AS AL) <10 30 <10 20 DIS- CHARGE, INST. CUBIC FEET PER SECOND 25 27 13 379 CALCIUM DIS- SOLVED (MG/L AS CA) 13 12 14 11 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 116 105 121 120 ARSENIC DIS- SOLVED (UG/L AS AS) 1 <1 <1 <1 SPE- CIFIC CON- DUCT- ANCE (US/CM) 176 156 192 90 MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) 5.3 4.7 5.8 4.9 SOLIDS, DIS- SOLVED (TONS PER DAY) 7.83 7.65 4.25 123 BARIUM, DIS- SOLVED (UG/L AS BA) 14 13 15 17 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.3 6.4 7.7 6.5 SODIUM, DIS- SOLVED (MG/L AS NA) 14 13 15 14 NITRO- GEN, NO2+NO3 DIS- SOLVED (MG/L AS N) 0.066 0.130 0.061 0.230 BERYL- LIUM, DIS- SOLVED (UG/L AS BE) <0.5 <0.5 <0.5 <0.5 TEMPER- ATURE WATER (DEC C) 26.0 23.0 24.0 24.0 SODIUM AD- SORP- TION RATIO 0.8 0.8 0.9 0.9 NITRO- GEN, AMMONIA DIS- SOLVED (MG/L AS N) 0.010 0.020 0.020 0.030 CADMIUM DIS- SOLVED (UG/L AS CD) <1 <1 <1 <1 TUR- BID- ITY (NTU) 0.70 1.2 1.8 43 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 0.60 0.60 0.60 0.60 NITRO- GEN, AMMONIA DIS- SOLVED (MG/L AS NH4) 0.01 0.03 0.03 0.04 CHRO- MIUM, DIS- SOLVED (UG/L AS CR) <1 <1 <1 <1 OXYGEN, DIS- SOLVED (MG/L) 6.6 8.6 8.4 8.1 ALKA- LINITY WAT WH TOT FBT FIELD MG/L AS CACO3 60 51 80 23 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) <0.20 <0.20 <0.20 0.40 COBALT, DIS- SOLVED (UG/L AS CO) <3 <3 <3 <3 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 91 108 106 102 SULFATE DIS- SOLVED (MG/L AS S04) 12 9.7 12 11 PHOS- PHORUS TOTAL (MG/L AS P) 0.020 0.030 0.020 0.050 COPPER, DIS- SOLVED (UG/L AS CU) <1 1 <1 <1 COLI- FORM, FECAL, 0.7 UM-MF (COLS./ 100 ML) 260 560 510 4700 CHLO- RIDE, DIS- SOLVED (MG/L AS CL) 12 12 12 9.7 PHOS- PHORUS DIS- SOLVED (MG/L AS P) 0.030 0.010 0.020 0.010 IRON, DIS- SOLVED (UG/L AS FB) 8 17 10 18 STREP- TOCOCCI FECAL, KF AGAR (COLS. PER 100 ML) 3000 430 390 12000 FLUO- RIDE, DIS- SOLVED (MG/L AS F) 0.10 <0.10 0.10 0.20 PHOS- PHORUS ORTHO, DIS- SOLVED (MG/L AS P) <0.010 <0.010 0.010 0.010 LEAD, DIS- SOLVED (UG/L AS PB) <1 <1 <1 <1 HARD- NESS TOTAL (MG/L AS CAC03) 54 49 59 48 SILICA, DIS- SOLVED (MG/L AS SI02) 24 21 23 24 PHOS- PHATE, ORTHO, DIS- SOLVED (MG/L AS P04) -- -- 0.03 0.03 LITHIUM DIS- SOLVED (UG/L AS LI) <4 <4 <4 <4 K = non-ideal count RIO QRANDB DB PATILLAS BASIN 50092000 RIO GRANDB DB PATILLAS NEAR PATILLAS, PR--Continued (National stream-quality accounting network station) WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 343 DATE OCT 1992 13. .. JAN 1993 14... APR 06... JUL 23... MANGA- NESE, DIS- SOLVED (UG/L AS MN) 4 9 13 5 MERCURY DIS- SOLVED (UG/L AS HG) 0.2 <0.1 <0.1 <0.1 MOLYB- DENUM, DIS- SOLVED (UG/L AS MO) < 10 <10 <10 <10 NICKEL, DIS- SOLVED (UG/L AS NI) 1 <1 <1 Kl SELE- NIUM, DIS- SOLVED (UG/L AS SB) <1 <1 <1 Kl SILVER, DIS- SOLVED (UG/L AS AG) <1.0 <1.0 <1.0 <1.0 STRON- TIUM, DIS- SOLVED (UG/L AS SR) 46 42 49 38 VANA- DIUM, DIS- SOLVED (UG/L AS V) <6 <6 <6 <6 ZINC, DIS- SOLVED (UG/L AS ZN) 7 4 2 7 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT DATE OCT 1992 13... JAN 1993 14... APR 06... JUL 23... TIME 0945 0925 0930 1000 STREAM- FLOW, INSTAN- TANEOUS (CFS) 25 27 13 379 SEDI- MENT, SUS- PENDED (MG/L) 17 8.5 19 109 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 1.13 0.62 0.66 112 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 56 79 89 87 344 THIS PAGE WAS LEFT BLANK INTENTIONALLY !*»r><j^. aivid* EXPLANATION A 1080 SURFACE-WATER STATION AND NUMBER T 1065 QUALITY-OF-WATER STATION AND NUMBER • 87 WELL AND WELL NUMBER *t i- Mop or so 0123456 KILOMETERS 01 234 MILES Figure 23.--South coast river basins the Rio Salinas to Rio Jacaguas basins. to •b 01 346 RIO SALINAS BASIN 50100200 RIO LAPA NEAR RABO DEL BUKY, 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 Salinae Plaza. DRAINAGE AREA.--9.92 mi a (25.69 km>). 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 except those for estimated daily discharges, which are poor. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV JAN FEB MAR MAY JUN AUG SEP 1 1.5 1.8 2 1.6 1.7 3 1.6 1.6 4 1.5 1.8 5 1.4 1.8 6 1.7 1.7 7 1.9 1.8 8 4.6 1.8 9 2.8 1.6 10 2.0 1.6 11 2.1 1.6 12 1.9 1.6 13 2.0 1.9 14 1.7 1.7 15 1.6 1.6 16 1.6 1.5 17 1.8 1.4 18 2.0 1.4 19 5.7 1.9 20 3.3 2.7 21 2.3 2.8 22 3.6 2.0 23 2.9 2.1 24 13 2.0 25 5.7 1.9 26 3.1 1.8 27 2.4 6.0 28 2.0 16 29 1.9 5.4 30 1.8 9.7 31 1.7 —— TOTAL 84.7 84.2 MEAN 2.73 2.81 MAX 13 16 MIN 1.4 1.4 AC-FT 168 167 CFSM .27 .28 IN. .32 .31 STATISTICS OF MONTHLY MEAN MEAN 19.2 8.01 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 4.2 2.9 2.6 2.3 2.1 1.9 1.8 1.8 1.7 1.6 1.6 1.6 2.4 2.0 1.9 1.8 1.6 1.5 1.5 1.5 1.5 1.5 1.6 1.5 1.4 1.5 1.7 1.5 1.4 1.3 1.3 56.5 1.82 4.2 1.3 112 .18 .21 DATA 2.36 6.09 1991 .96 1992 FOR 1.3 1.3 1.3 1.3 1.2 1.2 1.2 1.2 1.3 1.3 1.2 1.2 1.2 1.1 1.1 1.1 1.0 .95 .88 .88 .86 .86 .88 .88 .84 .81 .83 5.2 4.4 2.0 1.4 42.17 1.36 5.2 .81 84 .14 .16 1.2 1.1 1.0 .99 .95 .94 .94 .92 .88 .86 .83 .91 .97 1.0 1.1 1.1 1.1 1.1 1.0 .99 .99 1.0 1.1 .99 .94 .94 .91 .88 ___ --- 27.63 .99 1.2 .83 55 .10 .10 FOR WATER YEARS 1988 15.1 68.8 1992 .56 1990 3.59 12.4 1991 .49 1990 .90 .86 .83 .88 .88 .88 .88 .88 .87 .78 .81 .83 .83 .83 .84 .88 .88 .88 .88 .88 .86 .83 .81 .75 .69 .68 .65 .63 .61 .62 .59 24.90 .80 .90 .59 49 .08 .09 - 1993 1.16 2.08 1992 .44 1990 1992 CALENDAR YEAR 4147.63 11.3 1080 .84 .90 8230 1.13 15.43 7.8 2.1 1.4 Jan 5 Sep 18 Sep 13 .57 .54 .52 .53 .52 .46 .47 .51 .50 .51 .59 1.0 1.2 1.6 e2.0 el.O e.62 e6.2 e3.0 el. 6 .94 .82 .70 .70 .66 .80 .94 e4.0 e5.6 e2.6 --- 41.70 1.39 6.2 .46 83 .14 .16 , BY WATER 1.21 3.07 1992 .28 1990 FOR 1993 1165 3 129 1050 9 2310 4 4 1 e2.5 e3.5 el. 6 el.O el.l e.94 e.88 e.94 el. 3 el.O e.80 e.72 e4.6 e3.1 e2.0 el. 2 el. 9 el. 3 el. 3 1.2 1.1 1.1 1.7 3.5 4.0 3.0 1.7 1.3 1.0 .86 .83 52.97 1.71 4.6 .72 105 .17 .20 YEAR (WY) 8.05 36.6 1992 .18 1990 .88 .87 1.1 .84 .77 .74 .72 .71 .72 .73 .65 .60 1.6 1.8 49 10 4.1 3.7 125 70 10 6.0 4.1 3.5 3.0 2.6 2.4 2.2 2.2 2.1 312.63 10.4 125 .60 620 1.04 1.16 3.72 10.4 1993 .46 1989 WATER YEAR .30 .19 .46 .50 .61 .44 .32 .33 .1 .6 .81 Jul 11 Apr 6 Apr 4 Jul 11 Jul 11 Apr 6 2.0 2.0 2.0 2.0 1.9 1.9 2.0 1.9 1.9 1.9 129 17 5.2 3.9 3.4 3.2 2.9 2.8 2.7 2.6 2.5 10 6.2 5.7 4.9 4.1 3.7 3.5 3.2 3.0 2.9 241.9 7.80 129 1.9 480 .78 .90 2.35 7.80 1993 .14 1989 WATER 6 11 3 1080 15700 17 4630 8 8 1 2.9 2.8 2.7 2.7 2.6 2.7 2.7 2.6 2.7 2.6 2.6 2.5 2.8 2.7 2.8 44 4.9 3.2 2.7 2.5 2.4 2.3 2.7 2.6 2.4 2.3 e2.1 el. 9 el. 9 el. 8 e2.0 122.1 3.94 44 1.8 242 .39 .45 2.88 6.06 1990 .18 1989 YEARS 1988 - .40 .2 .13 Jan 5 .02 Aug 29 .07 Aug 24 Jan 5 . 82 Jan 5 .64 .69 .4 .4 .24 el. 8 el. 7 el. 8 4.9 1.6 1.5 1.4 1.3 1.2 1.1 1.1 1.1 1.1 1.2 1.3 1.2 1.9 1.7 1.6 7.8 2.1 1.7 4.5 3.6 4.4 3.1 2.7 2.8 2.7 8.0 --- 73.9 2.46 8.0 1.1 147 .25 .27 8.71 29.1 1989 .82 1991 1993 1991 1990 1992 1989 1989 1992 1992 e Estimated RIO SALINAS BASIN S0100450 RIO MAJADA AT LA PLENA, PR 347 LOCATION.--Lat 18°02'40", long 66«12'27", Hydrologic Unit 21010004, on right bank, upstream side of bridge on Hwy 712, about 0.3 mi (O.S km) southwest of La Plena. DRAINAGE AREA.--16.7 mi' (43.3 km'). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—January 1973 to April 1979 (montly measurements only), September 1988 to current year. GAGE.--Water-stage recorder. Elevation of gage is 410 ft (125 m), from topographic map. REMARKS.-Records fair. Some regulation at low flow upstream from station by local residents for agricultural purposes. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 .9 3.S 2 .4 3.2 3 .6 3.2 4 .1 4.2 S .3 4.1 6 .8 4.4 7 .0 5.1 8 .8 4.0 9 .4 3.9 10 .0 3.8 11 4.3 3.1 12 3.7 2.8 13 3.0 3.3 14 2.7 3.1 15 2.9 3.0 16 3.2 8.2 17 3.3 5.6 18 3.1 3.8 19 10 8.7 20 8.5 18 21 5.2 12 22 8.0 9.0 23 7.9 7.5 24 5.2 6.7 25 5.5 5.2 26 4.7 4.4 27 4.2 11 28 3.8 20 29 3.9 12 30 4.3 32 31 3.7 TOTAL 146.4 218.8 MEAN 4.72 7.29 MAX 10 32 MIN 2.7 2.8 AC-FT 290 434 CFSM .28 .44 IN. .33 .49 STATISTICS OF MONTHLY MEAN MEAN 18.8 9.81 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 16 11 8.6 7.4 6.2 S.4 4.8 4.6 .4 .4 .2 .0 .6 .7 .0 3.6 3.7 3.7 3.6 3.5 3.3 3.4 3.2 3.0 3.0 3.4 3.8 3.1 3.1 3.2 3.6 149.5 4.82 16 3.0 297 .29 .33 DATA 4.30 9.67 1991 1.22 1990 FOR 4.1 3.3 3.2 2.9 2.8 3.0 3.0 3.2 3.0 2.9 2.7 2.6 2.5 2.5 2.5 2.4 2.4 2.3 2.2 2.2 2.2 2.4 2.9 2.6 2.7 2.5 2.6 3.6 14 6.3 4.1 101.6 3.28 14 2.2 202 .20 .23 FOR WATER 16.2 68.8 1992 .98 1990 3.3 2.9 3.0 2.S 2.3 2.2 2.2 2.2 2.1 2.0 2.0 2.5 2.7 2.3 2.0 1.9 1.8 1.8 1.7 1.8 1.8 1.6 1.6 1.5 1.5 1.4 1.3 1.3 ___ ___ --- 57.2 2.04 3.3 1.3 113 .12 .13 YEARS 1973 4.27 12.1 1991 .63 1990 1.3 1.4 1.2 1.1 1.1 1.1 1.1 1.0 1.1 1.1 1.0 1.0 1.1 1.2 1.2 1.1 1.1 1.3 1.1 1.4 1.4 1.2 1.0 1.0 1.0 1.1 .99 .92 .93 .95 .90 34.39 1.11 1.4 .90 68 .07 .08 - 1993 2.11 3.92 1991 .59 1990 1992 CALENDAR YEAR 4722. 12. 1520 1. 1. 9370 . 10. 13 4. 2. 4 9 Jan 5 5 May 13 9 May 7 77 52 0 3 .80 .80 .75 .75 .65 .61 .61 .54 .91 1.9 .97 1.1 .98 1.6 2.4 2.8 1.2 .83 8.7 5.3 2.2 1.3 1.1 .98 .98 .92 1.1 1.3 5.6 7.8 --- 57.48 1.92 8.7 .54 114 .11 .13 3.6 3.S S.O 2.2 1.4 1.6 1.3 1.2 1.3 1.9 1.4 1.1 .98 6.7 4.2 2.3 1.6 2.6 1.8 1.8 2.0 2.0 2.1 2.6 2.4 2.7 2.8 2.5 2.5 2.4 2.3 73.78 2.38 6.7 .98 146 .14 .16 1.6 1.3 2.0 1.7 1.6 1.7 1.3 1.2 1.0 1.1 1.1 .80 .86 2.2 18 12 4.4 3.3 87 45 15 9.5 12 19 13 9.2 7.5 5.0 4.5 5.1 --- 288.96 9.63 87 .80 573 .58 .64 4.4 4.3 7.4 7.3 3.7 2.1 2.1 2.8 2.2 1.6 152 33 14 8.4 7.9 9.1 6.9 5.7 5.2 4.5 4.7 15 23 19 15 9.1 7.3 6.2 5.6 5.2 5.0 399.7 12.9 152 1.6 793 .77 .89 4.9 4.5 4.1 3.9 3.9 4.3 3.4 3.1 3.0 2.9 3.4 3.3 3.0 3.0 3.4 28 8.6 4.9 3.9 3.4 3.1 3.0 3.8 3.2 2.9 2.6 2.7 2.6 2.6 2.5 2.7 134.6 4.34 28 2.5 267 .26 .30 2.4 2.3 2.4 2.2 6.0 4.4 3.1 2.6 2.6 2.5 2.2 2.0 1.9 2.0 2.0 2.2 5.6 3.1 2.2 4.3 3.7 2.6 6.0 7.7 6.3 4.6 3.3 4.4 5.2 15--- 116.8 3.89 15 1.9 232 .23 .26 , BY WATER YEAR (WY) 1.96 3.69 1992 .58 1990 FOR 1993 1779 4 152 1030 7 3530 3 8 3 1 6.34 25.5 1992 .25 1990 4.96 12.1 1992 .53 1990 WATER YEAR .21 .87 .54 .67 .38 .29 .96 .5 .0 .1 Jul 11 Apr 8 Apr 2 Jul 11 Jul 11 4.28 12.9 1993 .62 1989 WATER 7 12 1 1520 1520 17 5230 5 9 2 3.24 7.74 1992 .73 1989 YEARS 1973 .23 .1 .61 Jan . 05 Jun .05 Jun Jan . 19 Jan .43 .88 .9 .4 .57 10.1 30.1 1989 1.50 1991 - 1993 1992 1990 5 1992 4 1990 4 1990 5 1992 5 1992 348 RIO COAHO BASIN 50106100 RIO COAMO AT COAMO, PR LOCATION.—Lat 18°05'00", long 66°21'16", Hydrologic Unit 21010004, on Highway 14 bridge, 0.8 mi (1.3 km) northeast from Pargue Atletico, 1.2 mi (1.9 km) southeast from (H.C.P.R.) Antena de Radio. DRAINAGE AREA.--3.5 mi* (112.7 km*). HATER-DISCHARGE RECORDS PERIOD OF RECORD.—January 1987 to current year. GAGE.—Hater-stage recorder and crest-stage gage. Elevation of gage is 335 ft (110 m), from topographic map. REMARKS.—Records poor. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1986 TO SEPTEMBER 1987 DAILY MEAN VALUES DAY 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 TOTAL MEAN MAX MIN AC -FT CFSM IN. STATISTICS OF MONTHLY MEAN DATA MEAN MAX (WY) MIN (WY) e5.9 e5.6 e9.8 e8.0 e6.1 e5.8 e6.4 e5.7 e5.9 e8.7 eV.O --_ ___ ___ ___ FOR HATER ___ ___ ___ ___ ___ e6.2 e5.6 e5.4 e5.5 e5.4 e5.2 eS.O e4.8 e4.6 e7.0 e!2 elO e30 e20 elO e7.0 e6.0 e5.4 eS.O e4.6 e4.5 e4.4 e4.5 e4.5 e4.4 e4.4 e4.6 e4.3 ___ ___ --- 200.3 7.15 30 4.3 397 .16 .17 YEARS 1987 7.15 7.15 1987 7.15 1987 e4.1 e4.1 e4.2 e4.2 e3.9 e3.8 e3.7 e3.7 e3.6 e3.7 e3.8 e3.6 e3.3 e2.8 e3.3 e3.8 e2.9 e2.9 e3.1 e2.7 e2.4 e2.4 e2.3 e2.5 e2.5 e2.2 e2.2 e2.1 e2.1 e2.0 e2.0 95.9 3.09 4.2 2.0 190 .07 .08 - 1987, 3.09 3.09 1987 3.09 1987 e2.1 e2.1 e2.0 el. 9 e2.5 e!9 e!2 e8.0 6.3 4.4 118 150 62 76 109 73 57 33 20 13 9.4 8.1 7.3 6.0 5.3 4.5 4.1 3.9 3.8 3.8 --- 827.5 27.6 150 1.9 1640 .63 .71 BY HATER 27.6 27.6 1987 27.6 1987 4.0 3.7 3.7 4.5 4.9 14 6.0 8.5 18 152 59 22 8.0 4.8 4.1 3.7 7.1 85 81 44 16 8.1 5.8 11 39 63 20 9.4 83 70 40 903.3 29.1 152 3.7 1790 .67 .77 YEAR (WY) 29.1 29.1 1987 29.1 1987 22 192 201 174 161 135 91 86 77 67 61 52 49 43 47 40 32 21 24 60 103 189 100 66 48 39 32 26 23 22 --- 2283 76.1 201 21 4530 1.75 1.95 76.1 76.1 1987 76.1 1987 18 16 15 17 28 15 15 13 11 10 9.4 9.0 7.9 8.4 9.4 9.5 8.2 8.0 7.6 7.7 16 12 8.5 8.0 7.9 7.0 7.4 8.4 7.4 6.5 12 344.2 11.1 28 6.5 683 .26 .29 11.1 11.1 1987 11.1 1987 9.7 6.8 7.6 9.2 12 8.6 7.0 6.0 5.4 6.9 5.6 5.3 4.9 4.9 35 17 7.6 6.7 6.4 5.5 5.2 4.8 4.1 4.1 4.1 3.6 3.6 3.6 3.4 3.1 3.4 221.1 7.13 35 3.1 439 .16 .19 7.13 7.13 1987 7.13 1987 3.9 4.3 4.1 4.4 4.0 3.8 3.6 2.8 3.1 3.2 3.1 22 4.4 3.3 3.2 3.0 2.8 38 13 11 6.2 6.2 5.7 5.7 5.5 4.5 4.3 3.8 3.6 9.1 --- 195.6 6.52 38 2.8 388 .15 .17 6.52 6.52 1987 6.52 1987 e Estimated 349 DAY RIO COAMO BASIN 50106100 RIO COAMO AT COAMO, PR--Continued DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1987 TO SEPTEMBER 1988 DAILY MEAN VALUES OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SBP 1 5.8 27 2 17 27 3 7.5 25 4 6.3 25 5 6.3 63 6 5.7 156 7 8.5 70 8 164 43 9 26 23 10 8.5 31 11 6.0 17 12 6.0 36 13 4.9 29 14 5.3 11 15 5.0 8.2 16 4.8 7.3 17 11 14 18 147 16 19 67 13 20 29 11 21 82 11 22 74 14 23 47 13 24 27 121 25 22 e!4 26 21 e80 27 74 564 28 50 153 29 37 149 30 32 116 31 29 TOTAL 1036.6 1887.5 MEAN 33.4 62.9 MAX 164 564 MIN 4.8 7.3 AC -FT 2060 3740 CFSM .77 1.45 IN. .89 1.61 STATISTICS OF MONTHLY MEAN MEAN 33.4 62.9 MAX 33.4 62.9 (WY) 1988 1988 MIN 33.4 62.9 (WY) 1988 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 FLOW INSTANTANEOUS PEAK STAGE ANNUAL RUNOFF (AC- FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 77 104 88 76 101 71 124 110 93 87 118 136 125 116 107 100 84 67 66 72 70 72 63 62 63 57 61 64 55 55 e54 2598 83.8 136 54 5150 1.93 2.22 DATA 83.8 83.8 1988 83.8 1988 eSO e54 e43 e42 e38 e38 e36 e36 e35 e35 e35 e34 e34 e33 e33 e33 e32 e30 e29 e28 e27 e28 e27 e27 e27 e27 e26 e26 e26 e26 e25 1020 32.9 54 25 2020 .76 .87 FOR WATER 32.9 32.9 1988 32.9 1988 e24 e24 e24 e24 e24 e24 e22 e20 e!9 e!9 e!8 e!8 e!8 e!7 e!6 e!5 e!4 14 13 13 12 12 11 12 12 14 15 12 12 ___ --- 492 17.0 24 11 976 .39 .42 13 13 11 10 9.5 9.5 11 10 10 10 10 9.5 9.6 11 11 10 11 9.9 8.5 8.3 8.5 8.2 8.3 7.8 8.1 8.5 8.6 9.8 11 9.7 9.2 303.5 YEARS 1987 - 12.1 17.0 1988 7.15 1987 FOR 1988 9532. 26. 564 1. 1. 1890 8. 9.79 13 7.8 602 .23 .26 8.4 8.1 7.9 8.4 8.1 23 17 e8.6 e8.4 e8.0 e7.8 e7.4 e7.4 eB.O e8.4 e9.7 e!2 e8.2 e7.4 e6.8 e6.8 e270 elO e8.6 e8.2 e8.2 e7.6 e7.3 e7.6 e!2--- 535.3 17.8 270 6.8 1060 .41 .46 1988, BY WATER 6.44 9.79 1988 3.09 1987 22.7 27.6 1987 17.8 1988 elO e9.0 7.6 7.8 7.9 8.8 9.1 8.9 11 12 11 9.5 8.5 8.2 8.3 7.6 7.2 6.9 7.4 7.1 6.1 5.5 5.3 4.7 4.5 3.9 4.2 3.7 4.0 4.3 4.4 224.4 7.24 12 3.7 445 .17 .19 YEAR (WY) 18.2 29.1 1987 7.24 1988 4.6 4.4 4.3 4.3 4.4 4.4 4.3 4.2 4.3 4.2 4.7 4.9 5.1 5.2 6.8 5.8 4.8 5.0 .7 .8 .7 .8 .8 e!2 elO e8.5 e8.5 eB.O e7.6 e7.2 --- 171.3 5.71 12 4.2 340 .13 .15 40.9 76.1 1987 5.71 1988 WATER YEAR 8 0 5 6 85 Nov 27 Aug 14 Aug 9 Oct 8 Oct 8 18910 . 8. 70 10 4. 60 15 2 e8.5 e9.8 e8.0 e7.0 e5.8 e4.8 e4.3 e4.0 e3.8 e3.7 e3.7 e3.5 e3.3 e3.1 e3.1 e!30 e!70 e24 e!3 elO e8.3 e7.4 e7.0 e6.1 e5.2 e4.6 e4.5 e3.8 e3.5 e3.3 e2.4 479.5 15.5 170 2.4 951 .36 .41 13.3 15.5 1988 11.1 1987 WATER 26 26 26 564 1 1 3130 9 18870 8 66 8 3 e2.0 el. 8 e21 e2.8 e2.2 el. 9 el. 8 el. 6 el. 6 el. 7 el. 7 el. 7 el. 6 el. 5 el. 5 el. 6 e21 e4.7 e26 e2.2 e2.0 e2.1 e3.5 e!46 e63 e!3 e9.8 e6.8 e5.3 e4.2 e4.1 361.7 11.7 146 1.5 717 .27 .31 9.40 11.7 1988 7.13 1987 YEARS 1987 .0 .0 .0 Nov .5 Aug .6 Aug Jun . 84 Jun .60 .14 .6 .6 e48 e20 elO e9.4 e8.8 e7.1 8.1 8.6 8.0 8.9 32 28 20 23 14 12 11 7.9 8.6 8.7 9.8 11 11 13 8.3 6.8 9.7 7.1 6.2 38 --- 423.0 14.1 48 6.2 839 .32 .36 10.3 14.1 1988 6.52 1987 - 1988 1988 1988 27 1987 14 1988 9 1988 2 1987 2 1987 e Estimated 350 DAY OCT RIO COAHO BASIN 50106100 RIO COAHO AT COAHO, PR—Continued DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1988 TO SEPTEMBER 1989 DAILY MEAN VALUES NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 16 7.9 2 9.3 8.3 3 9.6 6.9 4 10 6.4 5 9.0 5.8 6 8.0 5.0 7 7.4 5.1 8 6.9 5.0 9 6.1 5.8 10 29 6.0 11 15 6.5 12 10 9.2 13 9.7 18 14 8.8 25 15 7.9 14 16 7.9 12 17 7.5 40 18 7.6 33 19 7.4 22 20 8.4 16 21 10 13 22 9.2 11 23 9.7 12 24 9.0 12 25 7.6 23 26 18 21 27 15 11 28 7.9 7.3 29 6.6 5.1 30 12 4.5 31 14 —— TOTAL 320.5 377.8 MEAN 10.3 12.6 MAX 29 40 HIN 6.1 4.5 AC-FT 636 749 CFSM .24 .29 IN. .27 .32 STATISTICS OF MONTHLY MEAN MEAN 21.9 37.8 MAX 33.4 62.9 (WY) 1988 1988 MIN 10.3 12.6 (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 FLOW INSTANTANEOUS PEAK STAGE ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 4.1 4.1 4.6 4.1 3.9 3.9 3.7 3.7 3.8 3.7 3.6 3.6 4.0 3.8 3.8 3.6 3.4 4.6 3.9 3.7 3.2 3.1 3.2 3.2 3.4 3.7 3.4 3.1 3.2 4.0 4.2 115.3 3.72 4.6 3.1 229 .09 .10 DATA 43.8 83.8 1988 3.72 1989 FOR 3.8 3.7 3.4 3.6 3.8 3.4 3.0 2.7 2.7 2.8 2.9 3.5 3.9 3.2 2.7 2.4 2.9 3.4 3.1 2.7 2.5 2.4 2.5 2.3 2.3 2.2 2.2 2.1 2.1 2.0 2.0 88.2 2.85 3.9 2.0 175 .07 .08 2.0 2.2 2.4 2.2 2.0 2.2 1.9 2.0 2.0 2.3 2.1 2.0 2.2 2.4 2.5 5.8 88.3 7.7 4.8 4.9 3.8 3.5 3.4 3.1 3.0 2.6 2.6 2.8 ___ ___ 88.7 3.17 8.3 1.9 176 .07 .08 FOR WATER YEARS 1987 17.9 32.9 1988 2.85 1989 9.19 17.0 1988 3.17 1989 2.4 3.1 3.1 2.9 2.2 2.0 1.8 2.0 4.4 3.6 2.9 3.9 15 11 7.4 5.0 4.8 4.5 6.9 10 5.4 3.2 3.2 3.0 2.8 3.1 2.7 2.6 2.5 2.5 5.8 135.7 4.38 15 1.8 269 .10 .12 - 1989 5.75 9.79 1988 3.09 1987 1988 CALENDAR YEAR 4824.3 13.2 270 1.5 1.6 9570 .30 4.13 27 8.4 3.6 Apr 22 Aug 14 Aug 9 6.0 8.7 4.5 3.2 2.8 2.6 2.2 1.9 1.8 1.8 1.9 2.1 2.3 2.2 2.1 2.0 2.3 1.6 1.6 1.6 1.6 2.6 1.7 1.5 1.5 3.8 1.9 2.0 2.1 2.0 --- 75.9 2.53 8.7 1.5 151 .06 .06 , BY WATER 16.0 27.6 1987 2.53 1989 FOR 1989 3703. 10. 315 . . 3000 9. 7350 3! 14 3. 2.0 2.1 2.1 1.8 1.8 1.8 1.7 1.5 1.5 1.7 2.4 2.4 2.1 1.8 1.5 1.4 1.4 1.6 1.7 1.7 1.5 1.2 1.1 1.1 1.2 1.3 1.6 1.5 2.1 1.6 1.4 51.6 1.66 2.4 1.1 102 .04 .04 YEAR (WY) 12.7 29.1 1987 1.66 1989 1.4 4.7 4.4 7.1 6.7 4.0 3.5 3.1 2.5 2.2 1.7 1.1 1.0 1.0 .98 .97 1.1 e.99 e.96 e.93 e.89 1.2 .98 .99 .90 .91 .93 .85 .82 .87 59.67 1.99 7.1 .82 118 .05 .05 27.9 76.1 1987 1.99 1989 WATER YEAR 11 1 67 70 57 23 17 1 91 Sep 18 Aug 2 Jul 27 Sep 10 Sep 10 .85 .85 .87 .81 .83 .76 .91 .84 .75 .79 .87 .85 .78 .78 .87 .94 .76 .81 .77 .68 .70 .75 .77 .73 .73 .70 .73 .73 .69 .68 .70 24.28 .78 .94 .68 48 .02 .02 9.12 15.5 1988 .78 1989 WATER 18 26 10 564 3130 9 13120 5 50 6 1 .69 .67 1.7 2.4 11 3.3 2.7 4.2 2.6 3.0 135 18 8.9 3.9 2.8 2.5 2.0 3.0 18 5.5 64 10 8.2 7.8 8.3 4.6 3.9 9.6 5.5 8.3 5.6 367.66 11.9 135 .67 729 .27 .31 10.2 11.9 1989 7.13 1987 YEARS 1987 .1 .0 .1 Nov . 67 Aug . 7 0 Jul Jun .84 Jun .42 .66 .8 .8 4.0 3.4 2.9 2.2 1.9 29 19 6.1 27 253 48 13 7.0 4.5 3.7 2.6 4.5 315 145 110 71 53 264 203 84 54 41 77 91 58 --- 1997.8 66.6 315 1.9 3960 1.53 1.71 29.1 66.6 1989 6.52 1987 - 1989 1988 1989 27 1987 2 1989 27 1989 2 1987 2 1987 e Estimated DAY OCT RIO COAMO BASIN 50106100 RIO COAMO AT COAMO, PR—Continued DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1989 TO SEPTEMBER 1990 DAILY MEAN VALUES NOV DEC JAN FBB MAR APR MAY JUN JUL AUG 357 SEP 1 47 32 2 53 31 3 65 30 4 60 29 5 52 29 6 45 28 7 38 27 8 70 36 9 33 30 10 28 29 11 25 26 12 23 25 13 22 23 14 21 23 15 24 22 16 27 22 17 24 20 18 27 20 19 70 20 20 238 19 21 125 18 22 90 17 23 74 16 24 67 16 25 79 16 26 62 15 27 53 15 28 40 14 29 53 13 30 39 12 31 36 TOTAL 1710 673 MEAN 55.2 22.4 MAX 238 36 MIN 21 12 AC-FT 3390 1330 CFSM 1.27 .52 IN. 1.46 .58 12 11 11 10 10 11 11 11 11 10 11 10 10 10 10 11 10 9.3 9.2 9.3 8.0 7.8 8.2 8.4 8.1 8.1 7.6 7.5 7.8 8.2 7.8 295.3 9.53 12 7.5 586 .22 .25 STATISTICS OF MONTHLY MEAN DATA MEAN 33.0 32.6 MAX 55.2 62.9 (WY) 1990 1988 MIN 10.3 12.6 (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 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 32.4 83.8 1988 3.72 1989 FOR 8.9 8.6 7.8 7.4 6.0 5.8 5.6 5.9 6.3 6.3 6.1 6.4 6.1 6.4 6.4 5.7 6.6 6.1 5.3 5.8 5.5 5.6 5.4 5.5 5.7 6.4 e6.7 e6.8 e6.9 e6.3 e6.1 196.4 6.34 8.9 5.3 390 .15 .17 e5.9 e5.8 e6.0 e6.2 e6.1 e5.1 e6.0 e7.4 e7.0 e8.0 e7.0 e!5 ell elO ell e8.6 e8.2 e9.0 e6.6 e5.3 e5.0 e4.5 e4.3 e4.6 e5.0 e5.2 e4.9 e4.6 -__ .__ --- 193.3 6.90 15 4.3 383 .16 .17 FOR WATER YEARS 1987 14.0 32.9 1988 2.85 1989 8.62 17.0 1988 3.17 1989 e5.2 e5.8 e4.8 e3.8 e4.2 e4.9 e5.8 e5.4 e4.3 e5.2 e5.6 e5.7 e6.0 e4.8 e3.8 e3.0 e3.1 e3.3 e3.6 e3.9 e3.9 e3.8 e3.5 e3.1 e2.6 e2.7 e2.7 e3.0 e3.7 e4.0 e4.0 129.2 4.17 6.0 2.6 256 .10 .11 - 1990 5.36 9.79 1988 3.09 1987 1989 CALENDAR YEAR 5567.81 15.3 315 .67 .70 11040 .35 4.76 38 3.1 .91 Sep 18 Aug 2 Jul 27 e4.9 e4.6 e3.3 e3.6 e3.8 e3.8 e3.8 e3.8 e3.8 e3.7 e3.4 e4.7 e4.3 e3.7 e4.0 e3.5 e5.8 e8.6 e!2 e6.4 e4.7 e4.1 e4.3 e5.2 e8.4 e8.8 e5.0 e3.3 e3.0 4.6 --- 146.9 4.90 12 3.0 291 .11 .13 e6.9 e4.5 e2.8 e2.7 e2.5 e2.9 e3.6 e4.3 e4.7 e7.0 e9.2 e5.0 e4.2 e3.7 e3.9 e3.0 e3.0 e3.0 e2.8 e2.4 e2.4 e2.4 e2.1 e2.0 e2.0 el. 7 el. 7 e2.2 e2.8 e2.6 e2.7 106.7 3.44 9.2 1.7 212 .08 .09 e2.6 e2.2 e2.5 e3.1 el. 8 el. 6 el. 5 el. 4 el. 3 el. 4 el. 4 el. 4 el. 6 2.6 6.3 5.1 2.5 2.4 2.7 3.7 2.5 2.1 1.9 1.7 2.0 2.3 1.8 1.6 1.8 1.5 --- 68.3 2.28 6.3 1.3 135 .05 .06 1.7 1.4 1.7 1.4 1.6 1.9 1.9 2.0 1.8 el. 7 el. 4 el. 3 el. 2 el. 3 el. 4 el. 4 el. 4 el. 3 el. 5 el. 4 el. 3 el. 6 el. 6 1.7 1.7 1.6 2.0 2.8 2.4 2.4 2.1 51.9 1.67 2.8 1.2 103 .04 .04 2.2 2.1 1.9 2.9 2.4 2.1 1.8 1.6 1.8 2.0 1.9 2.4 2.1 2.3 e2.5 1.8 1.6 1.4 1.4 1.3 1.2 107 9.8 4.5 3.6 3.4 3.3 160 308 66 15 721.3 23.3 308 1.2 1430 .53 .62 7.6 4.8 19 6.1 85 48 32 28 60 40 21 18 188 414 139 28 15 11 8.5 6.9 6.0 5.4 6.2 21 172 116 57 44 44 98___ 1749.5 58.3 414 4.8 3470 1.34 1.50 , BY WATER YEAR (WY) 13.2 27.6 1987 2.53 1989 FOR 1990 6041 16 414 1 1 4740 10 1 11980 5 38 5 1 10.4 29.1 1987 1.66 1989 WATER YEAR .8 .6 Sep 14 .2 Jul 13 .3 Jul 12 Sep 14 .89 Sep 14 . 1 Aug 21 .38 .17 .7 .7 21.5 76.1 1987 1.99 1989 7.26 15.5 1988 .78 1989 WATER 17 26 10 564 4740 10 12740 5 47 6 1 13.5 23.3 1990 7.13 1987 YEARS 1987 .6 .0 .1 Nov . 67 Aug .70 Jul Sep .89 Sep .40 .49 .1 .8 36.4 66.6 1989 6.52 1987 - 1990 1988 1989 27 1987 2 1989 27 1989 14 1990 14 1990 e Estimated 352 DAY OCT RIO COAHO BASIN 50106100 RIO COAMO AT COAMO, PR--Continued DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1990 TO SEPTEMBER 1991 DAILY MEAN VALUES NOV DEC JAN PEB APR MAY JUN JUL AUQ SEP 1 219 114 2 115 102 3 48 91 4 27 88 5 23 94 6 23 78 7 21 72 8 61 64 9 175 62 10 170 61 11 111 59 12 170 60 13 357 57 14 381 51 15 348 48 16 545 48 17 278 49 18 222 46 19 236 43 20 273 181 21 1080 71 22 415 34 23 283 28 24 342 24 25 661 23 26 688 21 27 389 21 28 278 20 29 192 20 30 226 21 31 130 TOTAL 8487 1751 MEAN 274 58.4 MAX 1080 181 MIN 21 20 AC-PT 16830 3470 CPSM 6.29 1.34 IN. 7.26 1.50 STATISTICS OP MONTHLY MEAN MEAN 93.2 39.1 MAX 274 62.9 (WY) 1991 1988 MIN 10.3 12.6 (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 INSTANTANEOUS LOW PLOW ANNUAL RUNOFF (AC-PT) ANNUAL RUNOFF (CPSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 19 18 19 19 17 16 16 15 15 15 16 17 14 14 15 15 14 13 13 13 14 14 14 16 16 16 17 17 18 19 33 507 16.4 33 13 1010 .38 .43 DATA 28.4 83.8 1988 3.72 1989 POR 25 21 20 18 18 18 18 18 18 17 16 16 16 15 14 13 13 12 11 11 11 11 10 9.9 10 10 10 9.7 9.8 9.5 9.7 438.6 14.1 25 9.5 870 .33 .38 POR WATER 14.1 32.9 1988 2.85 1989 10 9.9 9.5 10 14 16 12 10 9.8 10 12 66 28 13 11 9.8 9.8 8.7 8.8 8.9 8.4 8.3 8.1 8.0 8.2 8.0 7.7 7.9 ___ ___ --- 351.8 12.6 66 7.7 698 .29 .30 YEARS 1987 9.40 17.0 1988 3.17 1989 8.2 7.5 7.7 8.1 8.5 8.3 8.2 7.8 8.2 7.7 7.7 7.4 7.2 7.1 6.9 6.9 6.7 6.7 6.8 6.8 6.6 7.7 8.6 7.4 6.6 25 12 7.9 7.2 7.0 6.3 252.7 8.15 25 6.3 501 .19 .22 - 1991 5.92 9.79 1988 3.09 1987 1990 CALENDAR YEAR 14108. 38. 1080 1. 1. 27980 . 12. 100 5. 1. 5 7 Oct 21 2 Jul 13 3 Jul 12 89 07 7 7 6.4 6.8 6.7 6.9 7.0 6.5 7.1 7.2 7.5 6.7 6.9 6.4 6.5 6.5 6.7 7.1 6.7 7.1 8.0 7.2 6.9 7.2 7.3 6.6 6.5 6.3 6.0 5.6 5.5 5.5 --- 201.3 6.71 8.0 5.5 399 .15 .17 12 12 7.8 7.2 6.2 5.5 5.3 5.2 5.5 5.4 55 8.2 8.7 11 7.5 6.4 6.4 6.3 6.0 6.0 7.1 5.5 5.0 5.0 5.2 5.0 .6 .4 .6 .5 .3 248.8 8.03 55 4.3 493 .18 .21 4.3 5.3 5.3 .7 .6 .3 .1 .0 3.9 3.9 4.0 5.5 4.4 3.5 3.2 3.0 2.7 2.4 2.3 2.5 3.9 3.8 3.1 3.0 2.9 2.6 2.6 2.6 2.7 3.1 108.2 3.61 5.5 2.3 215 .08 .09 4.1 3.2 3.0 2.8 2.5 2.4 2.5 32 11 4.1 3.5 3.2 3.0 2.7 2.9 153 25 9.1 6.1 5.0 .5 .5 .4 .2 .1 4.1 3.8 129 11 4.6 3.8 459.1 14.8 153 2.4 911 .34 .39 4.2 3.7 3.9 3.6 3.2 2.8 2.4 2.2 2.2 2.2 2.0 2.0 1.8 6.7 5.4 3.6 3.0 3.5 2.7 2.6 2.8 27 11 4.1 2.9 2.2 3.1 2.8 2.5 2.3 2.0 126.4 4.08 27 1.8 251 .09 .11 56 8.9 5.2 4.5 4.1 4.1 134 18 6.8 6.3 5.5 5.0 4.9 4.7 4.5 4.3 5.5 6.2 118 29 8.2 6.0 7.0 4.6 3.6 3.4 3.2 3.3 3.6 3.7 --- 482.1 16.1 134 3.2 956 .37 .41 , BY WATER YEAR (WY) 11.9 27.6 1987 2.53 1989 POR 1991 13414. 36. 1080 1. 2. 6200 11. 1. 26610 11. 74 7. 3. 9.90 29.1 1987 1.66 1989 WATER YEAR 0 8 Oct 21 8 Aug 13 1 Aug 7 Oct 20 92 Oct 20 2 Aug 31 84 47 9 0 17.9 76.1 1987 1.99 1989 8.77 15.5 1988 .78 1989 WATER 22 36 10 1080 6200 11 1 16210 6 52 6 2 11.6 23.3 1990 4.08 1991 YEARS 1987 .4 .8 .1 Oct . 67 Aug . 7 0 Jul Oct .92 Oct .1 Aug .51 .99 .8 .0 32.3 66.6 1989 6.52 1987 - 1991 1991 1989 21 1990 2 1989 27 1989 20 1990 20 1990 21 1990 RIO COAMO BASIN 50106100 RIO COAMO AT COAMO, PR—Continued DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1991 TO SEPTEMBER 1992 DAILY MEAN VALUES 3S3 DAY OCT NOV DEC JAN FEE MAR APR MAY JUN JUL AUQ SEP 1 3.5 14 2 3.4 13 3 3.2 10 4 2.9 8.7 5 2.9 8.1 6 3.0 7.4 7 3.1 28 8 3.2 14 9 4.8 11 10 4.2 9.4 11 3.5 8.4 12 3.1 7.6 13 2.8 7.5 14 2.7 7.6 15 2.5 7.4 16 2.4 7.0 17 2.4 6.7 18 2.4 6.4 19 2.3 6.1 20 21 6.1 21 5.5 6.0 22 75 6.0 23 25 6.0 24 14 6.0 25 12 6.7 26 11 6.2 27 10 6.6 28 10 7.1 29 11 7.0 30 45 6.6 31 29 —— TOTAL 326.8 258.6 MEAN 10.5 8.62 MAX 75 28 MIN 2.3 6.0 AC-FT 648 513 CFSM .24 .20 IN. .28 .22 STATISTICS OF MONTHLY MEAN MEAN 76.V 33.0 MAX 274 62.9 (WY) 1991 1988 MIN 10.3 8.62 (WY) 1989 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 6.2 6.0 5.6 5.8 5.9 5.8 5.6 5.4 5.5 5.1 5.2 5.1 5.3 5.2 5.0 5.4 5.4 5.2 5.4 5.6 5.8 6.0 5.9 5.7 5.9 5.8 5.4 5.6 5.6 5.4 5.7 172.5 5.56 6.2 5.0 342 .13 .15 DATA 23.8 83.8 1988 3.72 1989 FOR 6.0 5.7 5.3 5.6 e!580 e!30 e70 e54 e48 e52 e52 e40 e35 e32 e30 e27 e24 e22 e21 e20 e!9 e!9 e!9 e!9 e!8 el? el? e!6 e!6 elS e!4 2448.6 79.0 1580 5.3 4860 1.82 2.09 e!3 e!2 e!2 e23 e46 e38 e32 e22 e!8 e!7 el 6 el 4 e!4 e!3 e!2 ell elO elO elO e9.9 e9.4 e9.8 elO elO e9.0 e9.9 e9.0 e8.0 e7.8 ___ --- 435.8 15.0 46 7.8 864 .35 .37 FOR WATER YEARS 1987 27.0 79.0 1992 2.85 1989 10.4 17.0 1988 3.17 1989 e7.8 e8.1 e8.2 e8.1 e7.8 e8.0 e9.4 e!3 ell e8.0 e7.6 e7.4 e7.4 e7.2 e7.2 e8.1 e8.5 e8.6 e9.6 e9.4 e8.4 e7.8 e6.4 e6.0 e5.8 e5.6 5.4 6.1 5.8 5.9 8.1 241.7 7.80 13 5.4 479 .18 .21 - 1992 6.23 9.79 1988 3.09 1987 1991 CALENDAR YEAR 3426.9 9.39 153 1.8 2.1 6800 .22 2.93 14 6.3 2.9 Jul 16 Aug 13 Aug 7 12 9.5 7.2 6.6 6.5 6.5 6.6 6.1 6.9 11 7.8 7.7 7.7 7.6 8.6 8.5 12 9.0 22 e45 e33 e!7 e!2 9.6 8.7 8.5 8.4 7.3 7.3 7.4 --- 334.0 11.1 45 6.1 662 .26 .29 7.8 7.2 7.2 6.7 6.5 7.9 9.9 7.9 7.1 6.6 6.4 7.9 7.0 27 21 15 13 9.9 9.4 8.7 8.4 8.4 203 198 112 1220 87 40 28 29 24 2157.9 69.6 1220 6.4 4280 1.60 1.85 172 137 93 69 60 53 50 54 42 38 41 44 35 32 30 29 28 27 25 25 30 25 22 21 20 18 18 17 16 16 --- 1287 42.9 172 16 2550 .99 1.10 15 14 14 13 13 12 12 11 11 11 10 10 9.4 8.9 8.5 10 9.1 9.1 8.5 8.4 8.5 8.8 8.4 8.8 8.7 8.4 8.1 7.7 7.5 7.6 8.2 308.6 9.95 15 7.5 612 .23 .26 8.7 7.6 7.7 7.9 82 29 9.1 7.6 7.3 7.0 7.0 7.0 6.2 6.3 6.2 6.2 6.2 5.7 5.7 7.0 7.4 6.2 6.1 6.0 5.8 5.7 5.5 5.4 5.2 5.0 4.7 300.4 9.69 82 4.7 596 .22 .26 4.6 4.5 4.3 4.3 4.1 4.0 7.9 13 6.9 4.8 4.5 4.4 4.3 4.3 4.3 4.6 4.9 5.0 5.0 «.7 9.0 5.9 7.1 6.1 5.7 5.4 5.4 5.5 5.4 15 178.9 5.96 15 4.0 355 .14 .15 , BY HATER YEAR (WY) 11.8 27.6 1987 2.53 1989 FOR 1992 8450. 23. 1580 2. 2. 9290 13. 16760 . 7. 32 8. 5. 19.9 69.6 1992 1.66 1989 WATER YEAR 8 1 Jan 5 3 Oct 19 5 Oct 13 May 26 49 May 26 53 23 1 0 22.1 76.1 1987 1.99 1989 8.97 15.5 1988 .78 1989 WATER 22 36 10 1580 9290 13 1 16310 7 47 7 2 11.3 23.3 1990 4.08 1991 YEARS 1987 .5 .8 .1 Jan . 67 Aug .70 Jul May .49 May .1 Aug .52 .03 .2 .1 27.9 66.6 1989 5.96 1992 - 1992 1991 1989 5 1992 2 1989 27 1989 26 1992 26 1992 21 1990 e Estimated 354 DAY OCT RIO COAMO BASIN 50106100 RIO COAMO AT COAMO, PR—Continued DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 23 95 2 10 49 3 5.8 42 4 5.1 39 5 19 35 6 120 33 7 64 32 8 59 29 9 40 28 10 19 29 11 35 28 12 16 27 13 14 32 14 53 32 15 33 29 16 58 37 17 77 29 18 27 41 19 56 33 20 27 87 21 19 60 22 92 44 23 74 38 24 185 34 25 141 31 26 99 30 27 82 87 28 76 104 29 76 59 30 187 51 31 78 TOTAL 1869.9 1324 MEAN 60.3 44.1 MAX 187 104 MIN 5.1 27 AC-FT 3710 2630 CFSM 1.39 1.01 IN. 1.60 1.13 STATISTICS OF MONTHLY MEAN MEAN 73.9 34.8 MAX 274 62.9 (HY) 1991 1988 MIN 10.3 8.62 (HY) 1989 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 39 32 28 26 25 24 23 22 22 22 21 21 21 22 22 21 20 20 20 20 20 20 19 18 18 24 24 21 20 19 20 694 22.4 39 18 1380 .51 .59 DATA 23.6 83.8 1988 3.72 1989 FOR 19 19 18 17 17 16 16 16 16 16 15 15 14 15 15 15 14 13 13 13 13 13 14 13 13 13 12 78 86 29 20 616 19.9 86 12 1220 .46 .53 17 8.8 3.9 14 7.5 3.8 15 6.6 4.0 13 6.9 4.2 12 7.1 4.2 11 7.5 3.9 11 7.5 3.9 10 7.3 3.8 10 7.4 6.1 9.6 7.2 7.3 8.9 6.4 8.3 8.8 6.2 15 9.6 5.7 20 9.6 5.9 17 9.2 5.6 17 8.7 5.2 14 8.6 5.0 12 elO e8.4 e8.4 e8.2 e8.2 S8.0 8.0 8.0 7.9 7.9 7.9 ___ ___ --- .7 16 .7 9.3 .6 13 .7 16 .8 15 .4 12 .9 15 .4 14 .8 11 .5 11 .5 64 .4 109 .1 47 .0 276.9 178.3 500.7 9.89 5 75 16.7 17 8.8 109 7.9 4.0 3.8 549 354 993 .23 .24 13 .38 15 .43 15 47 32 16 15 17 14 13 14 16 14 12 12 29 19 14 13 12 10 12 12 12 12 20 21 21 41 12 9.1 8.1 7.9 522.1 16.8 47 7.9 1040 .39 .45 7.7 7.6 7.3 7.1 7.1 6.8 6.2 6.2 6.2 6.0 6.0 5.9 5.7 5.6 12 5.8 5.3 5.2 12 14 6.6 6.2 5.8 5.7 5.7 5.6 5.4 5.4 4.8 4.9 ... 201.8 6.73 14 4.8 400 .15 .17 5.0 4.8 4.7 4.7 4.5 4.6 4.6 4.5 4.5 4.5 24 13 12 11 11 10 9.8 9.3 9.1 8.7 8.5 8.9 9.3 8.8 8.6 8.4 8.2 8.0 7.7 7.7 7.7 256.1 8.26 24 4.5 508 .19 .22 7.4 7.4 7.4 7.4 7.2 7.1 7.1 7.1 7.0 6.8 7.1 7.4 7.7 7.8 7.8 46 8.9 7.8 7.6 7.4 7.3 7.1 7.1 7.1 7.1 7.1 7.5 11 7.6 6.8 6.5 269.6 8.70 46 6.5 535 .20 .23 6.5 6.5 6.5 6.5 79 67 29 14 11 12 10 9.0 8.7 8.6 8.4 8.7 11 11 11 30 18 13 60 14 9.1 9.4 8.8 50 16 48--- 600.7 20.0 79 6.5 1190 .46 .51 FOR WATER YEARS 1987 - 1993, BY WATER YEAR (WY) 25.8 79.0 1992 2.85 1989 10.3 6 17.0 9 16 12.5 79 27.6 1988 1988 1987 3.17 3 09 2.53 1989 1987 1989 1992 CALENDAR YEAR 11580 31 1580 4 4 22970 9 55 13 5 .8 .6 Jan 5 . 0 Sep 6 .4 Aug 31 .73 .90 .8 FOR 1993 7310 20 187 3 4 2810 9 14500 6 46 12 5 19.4 69.6 1992 1.66 1989 WATER YEAR .1 .0 Oct 30 .8 Apr 2 . 0 Apr 2 Oct 30 .58 Oct 30 .46 .25 .2 19.9 76.1 1987 1.99 1989 8.86 15.5 1988 .78 1989 WATER 22 36 10 1S80 9290 13 1 16010 6 47 7 2 10.9 23.3 1990 4.08 1991 YEARS 1987 .1 .8 .1 Jan . 67 Aug .70 Jul May .49 May .1 Aug .51 .90 .7 .4 26.8 66.6 1989 5.96 1992 - 1993 1991 1989 5 1992 2 1989 27 1989 26 1992 26 1992 21 1990 e Estimated 355 RIO COAMO BASIN 50106500 RIO COAMO NEAR COAMO, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°03'52", long 66°22'10", Hydrologic Dnit 21010004, on Highway 153 bridge, 0.4 mi (0.6 km) above Rio de la Mina, and 1.8 mi (2.9 km) south of Coamo plaza. DRAINAGE AREA.--46.0 mi 1 (119.1 km1 ). PERIOD OF RECORD.—Hater years 1978 to current year. WATER-QUALITY RECORDS, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 27. .. DEC 08... MAR 1993 01... APR 13... JUN 24... ADG 17. .. TIME 1415 1210 1245 1355 1515 1530 DIS- CHARGE, INST. CUBIC FEET PER SECOND 7.7 16 11 13 26 17 SPE- CIFIC CON- DUCT- ANCE (US/CM) 522 630 679 683 580 595 PH HATER WHOLE FIELD (STAND- ARD UNITS) 7.4 7.8 7.8 7.1 7.6 7.3 TEMPER- ATURE HATER (DEG C) 30.0 26.5 26.5 31.5 33.0 32.5 TUR- BID- ITY (NTU) 1.6 2.8 2.3 4.0 4.2 2.3 OXYGEN, DIS- SOLVED (MG/L) 6.0 8.1 8.0 4.8 4.0 3.2 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 79 106 102 63 54 60 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) <10 <10 10 16 50 <10 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 2700 280 3400 400 460 K120 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 60 300 90 2800 310 30 DATE OCT 1992 27... DEC 18... MAR 1993 01. .. APR 13... JUN 24... AUG 17... HARD- NESS TOTAL (MG/L AS HARD- NESS NONCARB WH HAT 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 HAT WH TOT FET FIELD MG/L AS SULFIDB TOTAL (MG/L SULFATB DIS- SOLVED (MG/L CHLO- RIDE, DIS- SOLVED (MG/L CAC03) CAC03 250 120 AS CA) AS MG) AS NA) 180 19 48 16 68 20 7.4 41 AS K) 0.2 2.7 4.3 37 5.7 9.1 0.4 1.2 CAC03 190 220 250 180 220 160 AS S) AS S04) AS CL) <0.5 26 39 <0.5 42 47 8.1 7.4 SOLIDS, RESIDUE DATE OCT 1992 27.. . DEC 18... MAR 1993 01... APR 13... JUN 24... AUG 17.. . FLUO- RIDE, DIS- SOLVED (MG/L AS F) 0.20 -- -- 0.20 __ 0.10 SILICA, DIS- SOLVED (MG/L AS SIO2) 31 -- — 33 -- 21 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 210 -- -- 303 -- 186 SOLIDS, DIS- SOLVED (TONS PER DAY) 0.38 -- — 11.0 __ 8.54 TOTAL AT 105 DEG. C, SUS- PENDED (MG/L) <1 3 14 1 32 <1 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 1.43 1.11 1.86 1.90 1.24 1.06 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.070 0.190 0.340 0.300 0.260 0.190 NITRO- GEN, N02+N03 TOTAL (MG/L AS N) 1.50 1.30 2.20 2.20 1.50 1.30 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.610 0.600 0.700 0.750 0.400 0.600 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.49 1.2 0.40 0.75 2.2 1.2 K = non-ideal count 356 DATE OCT 1992 27.. . DEC 08... MAR 1993 01... APR 13... JUN 24... AUG 17... DATE OCT 1992 27... DEC 08... MAR 1993 01... APR 13... JUN 24... AUG 17... RIO COAHO BASIN 50106500 RIO COAMO NEAR COAHO, PR--Continued HATER-QUALITY RECORDS, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 1.1 1.8 1.1 1.5 2.6 1.3 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) 2.6 3.1 3.3 3.7 1.8 2.2 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS NO3) 12 17 15 19 16 18 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.310 0.760 0.430 0.560 0.510 0.440 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 — -- 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 — — METHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 1200 360 20 50 150 <0.10 <0.10 <0.010 <0.010 0.07 0.17 RIO DESCALABRADO BASIN 357 50108000 RIO DESCALABRADO NEAR LOS LLANOS, PR LOCATION.—Lat 18°03'08", long 66°25'34", Hydrologic Unit 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» (33.4 km'). WATBR-DISCHARGB 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. RBHARKS.—Records poor. Some regulation at low flow by local resident upstream from station. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 e54 54 2 e40 e20 3 e!9 e!7 4 e9.6 e!8 5 e7.5 e!5 6 e25 el3 7 e40 e!3 8 92 e!2 9 12 e!2 10 186 ell 11 141 elO 12 e26 e9.0 13 13 e20 14 34 8.4 15 14 55 16 e232 27 17 e56 10 18 25 11 19 70 6.1 20 51 25 21 29 11 22 78 6.4 23 122 5.1 24 116 4.9 25 66 4.6 26 48 4.5 27 e42 11 28 e38 62 29 e32 11 30 e!20 90 31 24 TOTAL 1862.1 577.0 MEAN 60.1 19.2 MAX 232 90 MIN 7.5 4.5 AC-FT 3690 1140 CFSM 4.66 1.49 IN. 5.37 1.66 STATISTICS OF MONTHLY MEAN MEAN 31.8 17.4 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 ANNUAL RUNOFF (AC-FT) ANNUAL RUNOFF (CFSM) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 17 14 13 13 12 12 11 9.9 9.9 9.9 9.5 9.0 9.6 10 10 9.0 8.8 8.0 7.8 7.2 7.0 6.4 6.2 5.9 5.9 6.5 6.5 5.3 5.2 5.6 5.7 276.8 8.93 17 5.2 549 .69 .80 DATA 5.86 24.5 1988 .19 1968 FOR 5.5 5.2 5.1 4.9 4.6 4.0 3.7 3.8 3.8 3.4 3.2 3.4 3.4 3.4 3.3 3.2 3.5 3.4 3.3 3.5 3.9 .1 .6 .0 .4 .5 .4 7.1 14 10 7.0 145.6 4.70 14 3.2 289 .36 .42 FOR WATER 5.65 36.4 1992 .057 1968 5.1 4.9 5.3 .3 .2 .0 .1 .0 .0 3.8 3.3 3.5 3.2 2.8 2.5 2.6 2.7 2.4 3.0 3.0 2.2 1.9 1.7 1.9 2.0 1.9 1.6 1.4 ___ ___ —— 87.3 3.12 5.3 1.4 173 .24 .25 YEARS 1966 2.12 7.57 1986 .020 1968 2.1 1.6 1.1 1.1 el.O el.O 1.1 1.2 1.2 1.1 el.O e.98 e.98 el.O el.O e.98 .95 1.0 .95 .95 .84 .87 .91 .95 1.4 1.6 1.3 1.1 1.7 1.2 1.1 35.26 1.14 2.1 .84 70 .09 .10 - 1993 1.13 3.49 1986 .012 1968 1992 CALENDAR YEAR 6857. 18. 789 . . 13600 1. 19. 41 4. 1. 25 7 May 26 63 Jan 26 75 Jan 22 45 77 8 2 1.1 .94 1.1 1.1 1.1 1.0 .93 .93 .97 1.7 1.1 1.4 1.9 3.6 2.8 2.0 1.8 1.7 1.7 2.5 1.6 1.1 1.1 1.9 4.3 2.3 1.7 26 11 17 99.37 3.31 26 .93 197 .26 .29 8.9 51 19 11 8.6 6.8 5.8 4.4 17 10 4.2 2.9 2.3 elO e7.0 eS.O e3.5 e3.0 e3.5 e9.0 eS.O elO el2 e!3 e8.5 ell e!7 e!6 elO ell e!2 321.4 10.4 51 2.3 637 .80 .93 e9.0 e7.0 e6.0 eS.O e4.8 e4.3 e9.0 eS.O eS.O e4.0 4.0 3.7 3.6 4.9 9.2 10 5.4 4.9 46 16 5.8 5.5 .9 .9 .8 .7 .5 .4 .4 .6 --- 218.3 7.28 46 3.6 433 .56 .63 4.3 4.4 5.0 4.5 3.9 3.8 4.1 4.4 4.0 4.0 17 7.1 4.9 3.8 3.1 2.7 2.8 2.8 2.8 3.0 2.8 3.6 5.6 4.2 3.3 2.8 3.0 3.0 2.7 2.6 2.5 128.5 4.15 17 2.5 255 .32 .37 2.3 2.2 2.0 2.0 2.0 2.1 1.9 1.9 1.9 1.9 1.8 1.8 1.6 1.6 1.8 33 4.0 1.9 1.5 1.5 1.2 1.3 2.5 1.5 1.5 1.6 2.9 2.6 1.3 1.4 1.1 89.6 2.89 33 1.1 178 .22 .26 1.1 1.0 1.0 .96 1.8 29 2.8 1.2 1.0 11 2.4 1.5 1.2 1.2 .90 1.7 4.7 2.3 3.4 88 17 3.9 54 8.8 3.7 1.9 1.3 38 12 17 315.76 10.5 88 .90 626 .82 .91 , BY WATER YEAR (WY) 3.87 18.8 1985 .000 1968 FOR 1993 4156. 11. 232 . . 3060 9. 8250 . 11. 25 4. 1. 15.5 62.2 1985 .032 1968 WATER YEAR 99 4 Oct 16 84 Mar 21 92 Mar 17 Oct 10 94 Oct 10 88 99 3 1 5.35 25.2 1987 .000 1967 2.53 10.5 1991 .000 1967 WATER 9. 18. 1. 2600 . . 30000 24. 6930 . 10. 14 1. . 3.46 9.11 1988 .19 1990 YEARS 1966 57 4 89 Oct 00 Jun 00 Jun Oct 37 Oct 74 07 5 03 13.1 40.2 1985 .063 1967 - 1993 1986 1968 7 1985 22 1966 22 1966 7 1985 7 1985 e Estimated 358 RIO JACAGUAS BASIN 50110900 RIO TOA VACA ABOVE LAOO TOA VACA, PR 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 Limon. DRAINAGE AREA.--7.64 mi' (19.79 km1 ). HATER-DISCHARGE RECORDS PERIOD OF RECORD.—April 1989 to current year. GAGE.—Hater 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, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUQ SEP 1 59 36 2 23 33 3 12 26 4 11 23 5 49 20 6 160 17 7 86 16 8 68 15 9 48 14 10 49 13 11 50 12 12 34 12 13 26 14 14 50 12 15 54 13 16 52 31 17 40 14 18 32 11 19 32 10 20 31 45 21 25 49 22 25 32 23 132 21 24 65 17 25 44 14 26 33 13 27 32 13 28 34 66 29 27 78 30 52 55 31 42 TOTAL 1477 745 MEAN 47.6 24.8 MAX 160 78 KEN 11 10 AC-FT 2930 1480 CFSM 3.36 1.75 IN. 3.87 1.95 35 25 23 18 17 14 13 12 12 11 10 9.5 11 21 13 9.5 9.8 8.8 7.7 7.6 7.3 7.3 7.2 7.2 6.8 14 14 9.6 8.3 7.6 7.7 384.9 12.4 35 6.8 763 .87 1.01 STATISTICS OF MONTHLY MEAN DATA MEAN 52.6 19 . 8 MAX 109 40.1 (HY) 1991 1991 KEN 4.61 2.19 (HY) 1992 1992 SUMMARY STATISTICS ANNUAL TOTAL ANNUAL MEAN HIGHEST ANNUAL MEAN LOHBST 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 7.55 12.4 1993 1.42 1992 FOR 7.6 7.1 7.3 7.3 7.1 6.8 7.4 7.5 6.8 8.4 10 10 9.1 7.0 7.5 7.2 7.5 8.0 7.8 7.3 7.3 7.0 7.1 6.8 6.7 6.4 6.2 16 31 12 6.6 267.8 8.64 31 6.2 531 .61 .70 5.5 5.1 6.1 .8 .6, .4 .2 .1 .1 .1 .0 .3 .3 .3 .3 .2 .0 3.6 3.8 4.2 3.8 3.6 3.6 3.7 3.6 3.4 3.7 3.5 ___ —— 118.9 4.25 6.3 3.4 236 .30 .31 FOR HATER YEARS 1989 15.0 43.1 1992 3.75 1990 3.82 4.75 1991 2.37 1990 3.5 3.3 3.2 3.4 3.3 3.2 3.1 3.4 3.3 3.2 3.2 3.2 3.4 3.2 3.0 3.0 3.1 3.0 2.9 2.9 3.0 3.0 2.9 3.3 4.3 3.7 4.0 4.2 4.2 5.6 5.6 107.6 3.47 5.6 2.9 213 .24 .28 - 1993 3.41 4.71 1991 1.67 1990 1992 CALENDAR YEAR 7750.66 21.2 676 .85 2.3 15370 1.49 20.30 44 10 2.8 Jan 5 Jan 4 Mar 12 4.4 4.3 5.5 4.8 4.9 5.1 5.7 5.8 12 11 17 20 57 37 34 35 19 17 12 11 10 7.2 6.6 17 15 8.2 6.6 123 197 75—— 788.1 26.3 197 4.3 1560 1.85 2.06 35 34 38 22 15 11 8.8 8.1 34 16 11 8.8 8.3 30 16 12 9.9 9.1 8.5 10 30 22 35 42 26 25 58 53 32 35 38 741.5 23.9 58 8.1 1470 1.68 1.94 26 21 18 16 15 13 13 33 16 12 12 12 11 12 15 18 12 11 50 60 31 22 17 14 12 11 11 12 11 10 —— 547 18.2 60 10 1080 1.28 1.43 9.3 9.1 10 9.9 9.3 8.5 9.9 10 10 11 29 24 23 27 15 10 8.1 7.4 8.1 6.7 6.1 26 18 11 8.0 12 10 6.7 5.9 5.8 5.5 370.3 11.9 29 5.5 734 .84 .97 5.5 5.5 5.5 5.5 5.5 6.0 5.9 5.9 6.0 6.3 6.2 6.3 6.2 6.0 6.6 49 16 8.1 7.3 6.1 5.7 5.4 5.9 5.6 5.2 5.4 27 50 32 15 12 344.6 11.1 50 5.2 684 .78 .90 8.2 7.1 5.9 24 95 52 43 25 15 27 19 11 7.9 6.6 5.5 7.1 14 19 14 143 25 7.5 13 10 6.7 4.7 3.3 16 6.9 9.7 —— 652.1 21.7 143 3.3 1290 1.53 1.71 , BY HATER YEAR (HY) 10.4 26.3 1993 1.46 1990 FOR 1993 6544. 17. 197 2. 3. 2160 8. 2. 12980 1. 17. 41 10 3. 16.5 42.2 1992 1.42 1990 HATER YEAR 8 9 Apr 29 9 Mar 19 0 Mar 17 Oct 6 09 Oct 6 7 Mar 20 26 15 9 12.3 35.4 1992 1.23 1990 8.30 14.4 1992 .71 1990 WATER 15. 18. 10. 676 . . 8700 13. 11090 1. 14. 35 4. 1. 7.79 11.9 1989 2.74 1990 YEARS 1989 3 2 4 Jan 45 Aug 61 Jul Jan 24 Jan 44 Aug 08 65 3 2 24.8 46.2 1989 6.63 1992 - 1993 1991 1990 5 1992 7 1990 9 1990 5 1992 5 1992 7 1990 359 RIO JACAG0AS BASIN 50110900 RIO TOA VACA ABOVE LAGO TOA VACA, PR—Continued HATER-QUALITY RECORDS PERIOD OP RECORDS.— Hater years 1988 to current year. PERIOD OP DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: April 1988 to September 1993. INSTRUMENTATION.— Automatic sediment sampler. EXTREMES POR PERIOD OP DAILY RECORD.— SEDIMENT CONCENTRATION: Maximum daily mean, 3,170 mg/L January 05, 1992; Minimum daily mean, 1 mg/L several days. SEDIMENT LOADS: Maximum daily mean, 18,300 tons (16,600 tonnes) January 05, 1992; Minimum daily mean, 0.0 ton (0.0 tonne) several days. EXTREMES POR HATER YEAR 1993.-- SBDIMBNT CONCENTRATION: Maximum daily 4 mg/L several days. san, 1,270 mg/L Oct. 06, 1992; Minimum daily mean, SEDIMENT LOADS: Maximum daily mean, 2,680 tons (2,430 tonnes) Sept. 20, 1993; Minimum daily 0.04 ton (0.03 tonne) Sept. 27, 1993. SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) OCTOBER 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) 59 23 12 11 49 160 86 68 48 49 50 34 26 50 54 52 40 32 32 31 25 25 132 65 44 33 32 34 27 52 42 59 23 12 11 49 160 86 68 48 49 50 34 26 50 54 52 40 32 32 31 25 25 132 65 44 33 32 34 27 52 42 561 108 32 35 591 1360 957 692 202 404 425 210 73 560 142 379 137 53 146 128 49 20 1230 529 289 216 245 170 141 527 292 272 8. 1. 1. 278 2430 325 188 28 102 90 22 5. 182 27 122 16 4. 15 12 3. 1. 2090 109 36 20 26 17 13 134 40 5 1 8 6 9 4 6 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) NOVEMBER 36 33 26 23 20 17 16 15 14 13 12 12 14 12 13 31 14 11 10 45 49 32 21 17 14 13 13 66 78 55 222 168 109 82 55 30 20 20 20 19 19 20 46 35 36 249 56 36 23 419 378 172 95 47 33 25 22 656 830 428 25 15 7.9 5.3 2.8 1.4 .87 .79 .74 .67 .62 .61 3.2 1.2 1.4 80 2.1 1.1 .64 97 92 16 6.2 2.1 1.2 .85 .87 177 301 70___ MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CPS) (MG/L) (TONS/DAY) DECEMBER 35 25 23 18 17 14 13 12 12 11 10 9.5 11 21 13 9.5 9.8 8.8 7.7 7.6 7.3 7.3 7.2 7.2 6.8 14 14 9.6 8.3 7.6 7.7 187 104 108 63 45 33 17 10 11 15 17 14 33 153 36 14 12 11 9 7 7 7 8 8 8 65 34 8 10 10 11 18 7.1 8.9 3.3 2.0 1.3 .62 .31 .34 .42 .43 .34 2.6 29 1.3 .35 .29 .25 .19 .15 .14 .15 .16 .14 .14 6.8 1.6 .21 .21 .21 .21 TOTAL 1477 6620.9 745 915.56 384.9 87.16 360 RIO JACAGUAS BASIN 50110900 RIO TOA VACA ABOVE LAGO TOA VACA, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCBN- SEDIMENT MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE DAY (CFS) (MG/L) (TONS/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 7.6 7.1 7.3 7.3 7.1 6.8 7.4 7.5 6.8 8.4 10 10 9.1 7.0 7.5 7.2 7.5 8.0 7.8 7.3 7.3 7.0 7.1 6.8 6.7 6.4 6.2 16 31 12 6.6 12 17 20 20 21 21 21 21 21 19 17 14 11 10 9 9 9 10 10 10 10 10 10 9 9 9 9 223 202 33 13 FEBRUARY .23 5.5 .31 5.1 .38 6.1 .38 .38 .38 .41 .42 .37 .38 .39 .37 .28 .18 .18 .18 .18 .8 .6 .4 .2 .1 .1 .1 .0 .3 .3 .3 .3 .2 .0 .19 3.6 .20 3.8 .20 4.2 .20 3.8 .20 3.6 .18 3.6 .16 3.7 .16 3.6 .16 3.4 .16 3.7 41 3.5 35 1.3 .23 10 9 9 9 8 7 7 7 7 7 7 7 7 7 17 12 14 15 17 19 20 20 20 17 14 11 10 11 ___ .14 .12 .14 .12 .10 .08 .08 .08 .08 .08 .08 .08 .08 .08 .82 .14 .16 .15 .16 .18 .19 .19 .18 .16 .13 .11 .10 .11 ___ ___ MARCH 3.5 3.3 3.2 3.4 3.3 3.2 3.1 3.4 3.3 3.2 3.2 3.2 3.4 3.2 3.0 3.0 3.1 3.0 2.9 2.9 3.0 3.0 2.9 3.3 4.3 3.7 4.0 4.2 4.2 5.6 5.6 16 22 26 25 21 19 19 23 27 31 32 25 15 16 24 28 26 21 15 10 8 7 8 10 10 9 6 5 7 9 10 .15 .20 .23 .22 .19 .17 .17 .20 .24 .27 .27 .21 .13 .13 .19 .22 .20 .16 .11 .08 .07 .06 .07 .10 .11 .09 .07 .06 .08 .14 .16 TOTAL 267.8 84.74 118.9 4.12 107.6 4.75 RIO JACAQUAS BASIN 367 50110900 RIO TOA VACA ABOVE LAGO TOA VACA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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 4.4 4.3 5.5 4.8 4.9 5.1 5.7 5.8 12 11 17 20 57 37 34 35 19 17 12 11 10 7.2 6.6 17 15 8.2 6.6 123 197 75--- MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/ DAY) APRIL 5 6 9 18 28 23 13 11 58 37 93 84 1030 691 676 206 70 54 24 13 13 21 22 107 44 17 14 1230 1040 47 --- MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) (CFS) (MG/L) (TONS/DAY) MAY .06 .07 .13 .23 .37 .32 .19 .16 5.2 1.9 11 6.6 375 78 91 23 4.3 2.8 .72 .36 .36 .41 .36 14 2.0 .37 .25 709 974 12 --- 35 34 38 22 15 11 8.8 8.1 34 16 11 8.8 8.3 30 16 12 9.9 9.1 8.5 10 30 22 35 42 26 25 58 53 32 35 38 11 145 185 27 19 23 21 14 335 40 15 20 16 201 25 7 10 10 9 15 225 32 168 73 15 16 624 455 33 177 50 1.0 30 22 1.7 .75 .66 .50 .30 124 2.1 .39 .48 .35 32 1.2 .23 .24 .22 .20 .35 58 2.3 38 9.8 1.1 1.0 343 121 3.2 45 6.0 JUNE 26 21 18 16 15 13 13 33 16 12 12 12 11 12 15 18 12 11 50 60 31 22 17 14 12 11 11 12 11 10 ___ 20 21 24 28 28 25 25 311 44 32 30 28 25 30 49 48 17 25 411 294 29 25 21 20 26 37 49 56 50 36 --- 1.5 1.2 1.1 1.2 1.1 .91 .88 84 1.9 1.1 .98 .88 .70 .99 2.6 2.9 .49 .70 75 60 2.5 1.4 .91 .73 .81 1.0 1.5 1.7 1.4 .95 --- TOTAL 788.1 2314.16 741.5 847.07 547 253.03 362 RIO JACAGUAS BASIN 50110900 RIO TOA VACA ABOVE LAGO TOA VACA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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 9.3 9.1 10 9.9 9.3 8.5 9.9 10 10 11 29 24 23 27 15 10 8.1 7.4 8.1 6.7 6.1 26 18 11 8.0 12 10 6.7 5.9 5.8 5.5 370.3 6544.8 JULY 26 23 23 16 10 6 5 8 14 19 145 43 12 10 7 4 5 8 10 11 14 24 12 11 16 15 10 8 5 4 4 ... MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) AUGUST .64 .56 .58 .41 .21 .14 .13 .21 .37 .53 19 3.4 .69 .82 .26 .10 .11 .16 .22 .18 .21 2.4 .65 .28 .29 .41 .28 .14 .07 .05 .06 33.56 15263.53 5.5 5.5 5.5 5.5 5.5 6.0 5.9 5.9 6.0 6.3 6.2 6.3 6.2 6.0 6.6 49 16 8.1 7.3 6.1 5.7 5.4 5.9 5.6 5.2 5.4 27 50 32 15 12 344.6 6 8 8 8 5 4 4 5 6 6 6 6 6 6 9 23 17 8 5 8 7 7 7 6 7 7 167 369 84 19 9 ... .10 .12 .12 .12 .08 .06 .07 .08 .11 .10 .10 .09 .10 .11 .17 3.9 .79 .18 .10 .13 .11 .10 .10 .09 .10 .11 40 119 8.5 .78 .30 175.82 MEAN MEAN CONCEN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) SEPTEMBER 8.2 7.1 5.9 24 95 52 43 25 15 27 19 11 7.9 6.6 5.5 7.1 14 19 14 143 25 7.5 13 10 6.7 4.7 3.3 16 6.9 9.7 11 15 20 186 949 348 226 49 35 174 68 15 9 6 6 9 70 125 48 945 142 18 70 53 11 8 4 194 23 41 .23 .26 .30 35 950 70 27 3.5 1.5 26 4.5 .45 .18 .12 .09 .18 7.6 19 3.0 2680 14 .45 6.8 2.3 .16 .10 .04 C.6 1.3 2.6 652.1 3922.66 RIO JACAGUAS BASIN 50110900 RIO TOA VACA ABOVE LAGO TOA VACA, PR—Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT 363 DATE OCT 1992 23... APR 1993 13... 13.. . 28... 29... SEP 20... TIME 1730 1450 1600 2155 1535 1630 DIS- CHARGE, INST. CUBIC FEET PER SECOND 1250 204 208 159 594 2140 SEDI- MENT, SUS- PENDED (MG/L) 14000 3700 3380 21900 13600 3880 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) , 4720 2040 1900 9400 21800 22400 SED. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM . 11 43 41 16 14 40 SED. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM , 13 47 47 21 17 47 SED. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 15 61 56 25 18 54 DATE OCT 1992 23... APR 1993 13.. . 13... 28... 29... SEP SBD. SUSP. FALL DIAM. PERCENT FINER THAN 016 MM 19 72 69 31 23 SED. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM 23 81 79 39 30 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 29 91 88 47 40 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 41 96 94 59 56 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 59 99 98 76 74 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 85 99. 99. 92 91 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 97 7 99.9 5 99.8 99 99 364 RIO JACAGUAS BASIN 50110900 RIO TOA VACA ABOVE LAGO TOA VACA, PR—Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT DATE TIME STREAM- FLOW, INSTAN- TANEOUS (CFS) SEDI- MENT, SUS- PENDED (MG/L) SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM OCT 1992 23... ABR 1993 13... 28... 28... 28... 29... MAY 21.. . AUG 27... 1630 1415 1600 1630 1855 1650 1515 1700 200 192 104 120 342 816 168 73 8110 6230 2100 1430 2640 1130 1850 1120 4380 3230 590 463 2440 2490 839 221 66 50 76 83 75 90 80 97 RIO JACAGUAS BASIN 50111500 RIO JACAGUAS AT JOANA DIAZ, PR 365 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 Guayabal. DRAINAGE AREA.--49.8 mi 1 (129.0 km>). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--March 1984 to current year. GAGE.—Water-stage recorder and crest-stage gage. 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 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 35 151 2 20 118 3 10 92 4 8.1 65 5 14 52 6 348 50 7 354 44 8 196 41 9 94 28 10 378 30 11 188 30 12 105 25 13 60 84 14 72 75 15 78 116 16 74 204 17 110 112 18 96 86 19 57 86 20 53 278 21 33 166 22 65 105 23 301 e60 24 149 e45 25 115 e40 26 70 e35 27 58 eSO 28 56 e250 29 58 e80 30 206 e350 31 149 TOTAL 3610.1 2948 MEAN 116 98.3 MAX 378 350 MIN 8.1 25 AC-FT 7160 5850 CFSM 2.34 1.97 IN. 2.70 2.20 STATISTICS OF MONTHLY MEAN MEAN 152 113 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 elSO 113 103 104 95 78 66 65 48 47 44 39 40 58 67 50 34 27 23 17 16 23 27 31 54 48 65 34 32 36 36 1670 53.9 150 16 3310 1.08 1.25 DATA 44.5 151 1988 9.99 1989 FOR 37 29 30 27 22 20 13 15 17 17 9.6 7.3 7.0 8.6 11 12 16 19 9.3 9.7 11 13 8.4 9.0 6.0 5.1 5.0 6.0 172 81 53 706.0 22.8 172 5.0 1400 .46 .53 65 46 26 21 13 9.8 6.7 5.6 5.2 5.0 5.0 4.9 4.9 5.8 5.6 5.2 5.0 4.9 4.8 4.7 4.5 5.1 4.7 4.6 4.9 4.8 4.3 4.5 __- ___ --- 291.5 10.4 65 4.3 578 .21 .22 FOR WATER YEARS 1984 31.1 144 1992 5.88 1987 9.25 16.9 1991 4.82 1990 5.3 5.0 4.4 4.3 4.2 4.1 5.3 5.3 5.2 4.3 4.1 3.8 3.7 3.6 3.5 3.9 3.5 3.4 3.3 3.4 3.3 3.1 3.1 3.3 3.5 3.2 2.9 2.2 2.5 2.6 2.4 115.7 3.73 5.3 2.2 229 .07 .09 - 1993 5.07 7.94 1988 3.16 1992 1992 CALENDAR YEAR 25114.84 68.6 3170 .24 2.3 49820 1.38 18.76 138 29 4.1 Jan 6 Jan 3 Mar 6 2.2 2.3 2.2 2.3 2.5 4.0 6.0 6.2 6.4 6.1 5.9 6.0 6.7 8.8 8.3 7.7 6.9 6.6 6.8 7.6 8.0 7.9 7.5 8.1 8.2 6.8 6.6 74 404 184 826.6 27.6 404 2.2 1640 .55 .62 141 176 111 40 31 25 28 21 217 75 28 15 11 94 61 47 e41 e33 e36 38 179 125 62 92 92 344 589 243 85 79 77 3236 104 589 11 6420 2.10 2.42 62 104 74 68 65 47 38 236 122 88 71 71 64 76 74 66 49 46 110 160 99 75 48 50 56 56 47 47 74 57 --- 2300 76.7 236 38 4560 1.54 1.72 52 48 60 57 27 24 34 36 39 51 60 93 62 63 56 70 65 50 36 45 32 31 41 30 23 14 13 13 13 14 14 1266 40.8 93 13 2510 .82 .95 13 elO e9.8 e9.0 e8.0 e7.0 e7.1 e6.5 e6.6 e6.6 e6.6 e6.8 e6.4 e6.4 e7.6 e!3 e28 e30 e28 e23 e23 e49 e57 e28 e26 e!8 e!7 e!8 e!6 el? e27 535.4 17.3 57 6.4 1060 .35 .40 e24 e31 e28 e28 e69 e49 e46 e20 e!9 e!6 e23 e20 e!6 e!5 e!5 e21 e25 e29 e33 e60 e47 e23 e20 e25 e28 e30 e31 e42 e47 e42 --- 922 30.7 69 15 1830 .62 .69 , BY WATER YEAR (WY) 11.0 34.7 1992 3.19 1991 FOR 1993 18427. 50. 589 2. 2. 9480 16. 36550 1. 13. 110 29 4. 83.3 215 1985 2.68 1984 WATER YEAR 3 5 May 27 2 Mar 28 3 Mar 28 May 27 78 May 27 01 76 7 48.6 198 1987 2.72 1984 26.3 82.4 1987 2.94 1990 WATER 50 80 13 4530 1 40000 29 36620 1 13 110 8 3 20.9 41.1 1985 2.25 1990 YEARS 1984 - .5 .9 .0 Nov 27 .24 Jan 3 . 3 Sep 7 Oct 7 .42 Oct 7 .01 .79 .7 .5 39.0 164 1985 5.32 1986 1993 1986 1989 1987 1992 1990 1985 1985 e Estimated 366 THIS PAGE WAS LEFT BLANK INTENTIONALLY ^ / /! S V i ->,-».^.!:^>, *>„ ^-v -*»/ \ l~3~{ ) ?\f \ r(V«7,V > '\ ?f/s ^-\^k 'i. -. EXPLANATION A 1125 SURFACE-WATER STATION AND NUMBER QUALITY-OF-WATER STATION AND NUMBER 132 WELL AND WELL NUMBER 125780 LAKE-ELEVATION STATION 01234 MILES Figure 24.--South coast river basins the Rio Inabon to Rio Loco basins. CO 0) N 368 RIO INABON BASIN 50112500 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 Concordia, 0.4 mi (0.6 km) upstream from diversion canal, 0.5 mi (0.8 km) north of Real Abajo, and 6.1 mi (9.8 km) northeast of Plaza Degetau in Ponce. DRAINAGE AREA.--9.70 mi 1 (25.12 km'). WATER-DISCHARGE RECORDS PERIOD OP RECORD.--1962-63 (annual low-flow measurements only), February to June 1964 (monthly measurements only), July 1964 to July 1970, April 1971 to current year. GAGE.—Water-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, satellite telemetry at station. Gage-height and precipitation DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN PEB MAR APR MAY JUN JUL SEP 1 30 46 2 20 37 3 16 33 4 35 30 5 43 28 6 86 27 7 68 25 8 53 23 9 69 23 10 81 22 11 55 21 12 41 25 13 35 26 14 48 27 15 42 30 16 52 62 17 51 52 18 43 43 19 35 35 20 32 91 21 29 65 22 28 50 23 78 41 24 98 35 25 84 31 26 57 26 27 47 19 28 42 30 29 71 25 30 51 18 31 43 —— TOTAL 1563 1046 MEAN 50.4 34.9 MAX 98 91 MIN 16 18 AC-FT 3100 2070 CFSM 5.20 3.59 IN. 5.99 4.01 STATISTICS OF MONTHLY MEAN MEAN 48.6 35.4 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 15 14 11 11 10 9.2 8.1 7.8 7.1 6.8 6.8 6.8 7.2 8.6 7.8 5.7 5.3 4.8 7.1 7.8 7.1 9.2 11 12 12 13 14 12 14 13 11 296.2 9.55 15 4.8 588 .99 1.14 DATA 12.8 26.5 1966 4.43 1977 FOR 9.9 9.9 9.6 9.2 8.5 8.4 8.1 7.7 7.6 7.6 7.7 8.3 7.9 6.6 7.0 7.6 9.1 8.9 8.8 9.5 9.3 8.6 7.8 6.6 6.1 6.3 7.7 e25 e40 12 8.9 306.2 9.88 40 6.1 607 1.02 1.17 FOR WATER 8.75 45.5 1992 4.11 1989 14 9.5 9.0 7.6 6.8 6.5 6.5 6.7 7.0 7.2 7.3 8.4 8.5 8.4 8.5 9.9 8.7 7.1 7.1 6.0 5.7 4.9 5,0 5.4 5.0 5.2 5.5 5.4 ___ —— 202.8 7.24 14 4.9 402 .75 .78 YEARS 1964 5.35 9.25 1992 3.05 1977 5.6 5.7 5.0 4.4 4.4 5.1 5.6 6.4 7.1 5.6 5.2 6.2 6.4 6.8 8.8 5.0 4.5 4.1 3.4 3.8 3.9 3.5 2.9 3.7 5.1 4.8 4.0 3.2 3.6 6.4 6.3 156.5 5.05 8.8 2.9 310 .52 .60 - 1993 5.70 16.4 1972 1.85 1977 1992 CALENDAR YEAR 7811. 21. 686 4. 4. 15490 2. 29. 43 11 5. 1 3 Jan 6 0 May 22 4 Mar 12 20 96 3 3.4 2.5 7.2 5.6 3.1 2.7 3.4 3.2 6.3 4.4 9.8 13 24 10 6.1 9.0 4.7 5.5 8.8 6.1 7.0 8.3 6.4 12 9.8 6.8 7.4 25 81 75—— 377.5 12.6 81 2.5 749 1.30 1.45 106 94 79 48 35 28 21 18 35 14 8.8 8.5 8.2 14 8.9 18 11 12 12 12 49 31 39 47 49 82 222 143 84 66 48 1451.4 46.8 222 8.2 2880 4.83 5.57 40 35 28 24 24 20 22 19 22 14 11 9.6 11 17 17 17 14 12 26 24 15 13 13 13 12 12 12 23 18 17—— 554.6 18.5 40 9.6 1100 1.91 2.13 13 12 16 13 12 12 14 14 14 14 27 24 16 18 14 12 11 10 9.9 9.9 9.2 11 12 9.5 8.5 9.2 8.7 7.0 6.0 5.5 5.9 378.3 12.2 27 5.5 750 1.26 1.45 6.8 7.1 6.7 6.8 6.9 7.2 7.2 8.7 9.8 11 10 11 9.3 9.6 11 28 13 12 11 12 13 15 17 12 10 16 16 17 12 10 12 355.1 11.5 28 6.7 704 1.18 1.36 9.7 8.4 8.5 46 22 10 7.7 6.3 6.3 13 5.9 4.2 4.7 4.7 4.6 6.0 11 10 8.1 11 10 10 15 14 8.3 8.9 7.5 29 19 27—— 356.8 11.9 46 4.2 708 1.23 1.37 , BY WATER YEAR (WY) 8.17 19.2 1992 2.76 1975 FOR 1993 7044 19 222 2 3 1880 15 13970 1 27 46 11 5 20.5 76.7 1969 1.94 1967 WATER YEAR .4 .3 May 27 . 5 Apr 2 .6 Mar 18 May 27 .00 May 27 .99 .02 .3 16.6 49.8 1969 2.75 1967 12.4 32.7 1979 1.77 1990 WATER 18 30 9 2500 1 19000 25 13480 1 26 41 9 3 17.4 46.1 1979 4.47 1974 YEARS 1964 .6 .9 .57 Sep .80 Jul .1 Mar Oct . 3 0 Oct .92 .06 .2 .2 33.0 119 1975 7.70 1986 - 1993 1969 1974 16 1975 23 1977 31 1977 7 1985 7 1985 e Estimated RIO BUCANA BASIN 50113800 RIO CBRRILLOS ABOVE LAGO CERRILLOS NEAR PONCE, PR 369 LOCATION.--Lat 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 Maraguez. 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. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEE MAR APR MAY JUN JUL AUG SEP 1 36 108 2 30 78 3 27 66 4 52 60 5 73 52 6 174 48 7 136 43 8 136 39 9 178 36 10 169 34 11 130 32 12 91 58 13 73 59 14 84 46 15 91 41 16 96 91 17 119 88 18 98 68 19 78 48 20 66 140 21 55 95 22 54 68 23 234 51 24 253 43 25 201 38 26 159 35 27 134 34 28 115 54 29 161 76 30 108 51 31 91 --- TOTAL 3502 1780 MEAN 113 59.3 MAX 253 140 MIN 27 32 AC-FT 6950 3530 CFSM 9.49 4.99 IN. 10.95 5.56 STATISTICS OF MONTHLY MEAN MEAN 95.7 40.9 MAX 154 59.3 (WY) 1991 1993 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 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 37 34 32 31 29 29 28 27 27 26 26 27 28 27 23 23 23 23 22 21 21 21 21 20 25 22 21 33 25 21 812 26.2 39 20 1610 2.20 2.54 DATA 18.3 26.2 1993 13.3 1989 FOR 19 19 19 18 17 17 17 17 16 15 15 15 14 15 14 14 14 14 13 12 12 12 12 11 11 11 11 47 128 29 21 619 20.0 128 11 1230 1.68 1.94 20 17 16 15 14 13 13 13 13 13 12 12 12 12 12 16 14 12 13 12 12 11 11 11 11 11 11 11 ___ ___ --- 363 13.0 20 11 720 1.09 1.13 FOR WATER YEARS 1989 21.6 59.0 1992 7.46 1989 9.65 13.2 1992 6.34 1990 11 11 11 10 10 9.7 9.6 9.6 11 9.6 8.6 8.6 8.6 8.6 9.2 9.1 8.2 7.8 7.8 7.5 8.9 7.3 7.3 7.9 9.0 9.4 8.8 8.6 7.8 8.6 8.4 278.5 8.98 11 7.3 552 .75 .87 - 1993 12.2 27.5 1989 4.77 1990 1992 CALENDAR YEAR 14620.3 39.9 717 7.1 8.7 29000 3.36 45.70 85 22 10 Jan 6 Jan 4 Mar 2 7.4 7.3 8.7 7.6 7.3 7.1 7.4 8.5 9.6 8.6 30 19 43 24 34 21 13 15 15 13 12 12 12 16 14 12 11 20 142 96--- 653.5 21.8 142 7.1 1300 1.83 2.04 65 118 87 40 23 24 19 17 81 41 22 18 16 24 17 33 21 17 16 18 148 78 65 80 77 elSO e270 e208 135 102 84 2114 68.2 270 16 4190 5.73 6.61 65 56 45 42 35 34 34 32 54 33 29 27 26 27 25 26 23 22 46 46 28 26 23 22 22 21 21 34 26 22 972 32.4 65 21 1930 2.72 3.04 19 18 34 21 19 19 22 19 17 17 50 29 27 25 20 19 18 17 17 17 16 19 18 17 16 18 17 15 15 14 14 623 20.1 50 14 1240 1.69 1.95 14 14 13 13 13 13 13 13 14 14 13 13 12 12 13 49 17 14 14 13 14 17 16 14 14 14 30 16 14 16 19 488 15.7 49 12 968 1.32 1.53 15 13 29 21 17 16 16 17 18 76 38 22 21 19 18 19 18 32 23 37 24 20 30 25 19 41 30 47 36 69 826 27.5 76 13 1640 2.31 2.58 , BY WATER YEAR (WY) 16.7 24.3 1989 6.38 1990 FOR 1993 13031 35 270 7 7 1480 4 6 25850 3 40 85 20 10 30.4 68.2 1993 4.58 1990 WATER YEAR .0 .7 May 27 .1 Apr 6 .5 Apr 1 Oct 24 .95 Oct 24 .9 Apr 6 .00 .74 24.5 36.5 1989 6.37 1990 16.0 26.7 1991 4.66 1990 WATER 30 35 22 717 3 3 8140 9 3 21770 2 34 68 15 5 28.0 53.1 1991 11.4 1990 YEARS 1989 - .1 .7 .9 Jan 6 .3 Aug 16 .5 Aug 14 Jan 5 .65 Jan 5 .3 Aug 16 .53 .31 .4 52.3 88.0 1989 27.5 1993 1993 1993 1990 1992 1990 1990 1992 1992 1990 e Estimated RIO BOCANA BASIN 50113950 LAGO CBRRILLOS AT DAMSITE, PR LOCATION.--Lat 18°04'41", long 66°34'38", Hydrologic Dnit 21010004, on left bank west from intake house of dam, 0.7 ml (1.1 km) southwest from Iglesia San Mateo at Real Abajo, 3.2 ml (5.1 km) northeast from Hospital de Distrito de Ponce, and 2.2 mi (3.5 km) northwest from Bscuela Yuca. DRAINAGE AREA.--17.4 mi» (45.1 km'). ELEVATION RECORDS PERIOD OF RECORD.--October 1992 to September 1993. GAGE.--Water-stage recorder. Datum of gage is mean sea level. REMARKS.--Lake is formed by Cerrilloas Dam, a rockfilled ungated structure completed in 1992. Elevation of crest is 611 ft (186 m) above mean sea level, with a structural height of 323 ft (98 m) and a lenght of 1,555 ft (474 m) . The dam has a capacity of approximately 47,900 ac-ft (59.1 hm1 ) . The dam is operated by D.S. Army Corps of Engineers and its purpose is for flood control, water supply, power generation, and recreation. Gage-height and precipitation satellite telemetry at station. EXTREMES OBSERVED FOR CURRENT YEAR.--Maximum elevation, 523.56 ft (159.58 m), Sept. 30; minimum elevation, 417.23 ft (127.17 m), Oct. 1. Capacity Table (based on data from D.S. Army Corps of Engineers) Elevation , in feet Contents in acre-feet Elevation, in feet Contents in acre-feet 328 0 492 10,621 426 3,206 525 16,990 ELEVATION (FEET NGVD), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY OBSERVATION AT 24s00 VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 419.40 478.71 495.43 498.94 504.51 506.63 507.86 516.61 519.87 520.37 519.43 517.74 2 421.35 479.28 495.52 499.06 504.69 506.67 507.87 518.88 519.85 520.47 519.42 517.85 3 422.32 479.77 495.43 499.23 504.83 506.71 507.99 519.78 520.23 519.67 519.50 518.09 4 423.77 479.63 495.53 499.36 504.82 506.73 508.02 520.14 520.50 519.65 519.53 518.30 5 425.09 479.61 495.83 499.48 504.93 506.77 508.04 520.37 519.51 519.78 519.55 518.40 6 428.12 483.26 496.15 499.59 505.00 506.81 508.05 520.45 519.74 519.89 519.59 518.49 7 432.94 483.76 496.30 499.72 505.10 506.84 508.06 520.19 519.92 520.07 519.68 518.55 8 436.75 484.19 495.99 499.80 505.17 507.00 508.11 519.59 519.91 520.23 519.70 518.58 9 439.58 484.63 495.43 499.93 505.24 507.06 508.20 520.70 519.53 520.32 519.72 518.69 10 442.05 485.02 495.22 500.02 505.31 507.10 508.23 519.72 519.74 519.37 519.84 519.62 11 444.79 485.41 495.46 500.12 505.36 507.14 508.45 519.73 519.93 519.58 519.86 519.93 12 446.69 486.22 495.70 500.22 505.45 507.16 508.65 519.90 520.12 519.87 519.91 520.04 13 448.28 486.95 495.91 500.32 505.53 507.20 509.31 520.06 520.31 520.07 519.96 520.17 14 450.18 487.49 496.16 500.39 505.60 507.24 509.59 519.55 520.06 520.29 520.00 520.21 15 451.73 488.08 496.41 500.50 505.65 507.37 509.85 519.67 519.79 520.09 517.38 520.32 16 452.49 489.60 496.54 500.58 505.83 507.39 510.05 519.95 520.00 519.97 518.16 520.35 17 454.12 491.13 496.60 500.69 505.92 507.42 510.14 520.18 520.12 520.07 518.30 520.46 18 454.61 491.96 496.73 500.75 505.97 507.43 510.25 519.89 520.17 A 518.35 520.71 19 455.33 492.45 496.85 500.83 506.13 507.45 510.33 519.55 519.83 A 518.46 520.82 20 456.44 494.71 496.80 500.93 506.19 507.45 510.47 519.76 519.79 A 518.52 521.14 21 457.35 494.59 496.93 501.00 506.25 507.47 510.53 521.42 520.03 520.10 518.65 521.31 22 458.23 494.72 497.06 501.07 506.30 507.49 510.60 519.88 520.25 519.58 518.90 521.43 23 466.62 494.62 497.22 501.16 506.36 507.49 510.65 519.93 520.38 519.66 517.75 521.64 24 467.13 494.92 497.37 501.23 506.40 507.58 510.81 520.35 520.37 519.83 517.05 521.84 25 467.19 494.80 497.47 501.30 506.43 507.64 510.89 520.04 520.39 519.90 517.04 521.95 26 27 28 29 30 31 MEAN 450.47 488.71 496.63 500.76 505.66 507.28 509.78 519.97 520.02 --- 518.67 520.36 MAX 477.67 495.32 498.81 504.33 506.60 507.85 515.41 521.51 520.50 —— 520.00 523.41 MIN 419.40 478.71 495.22 498.94 504.51 506.63 507.86 516.61 519.51 —— 517.04 517.74 A No gage-height record 469.57 471.10 472.25 474.95 476.49 477.67 494.99 495.32 495.10 495.11 495.30 ___ 497.69 497.87 498.02 498.42 498.61 498.81 501.36 501.47 502.16 503.78 504.15 504.33 506.46 506.52 506.60 ___ ___ 507.67 507.70 507.74 507.78 507.79 507.85 510.93 511.00 511.28 513.73 515.41 ___ 520.72 521.51 520.64 519.88 519.95 520.00 520.48 519.57 519.88 520.07 520.27 -__ 520.04 520.13 520.24 520.29 520.35 520.40 517.07 517.29 517.46 517.53 517.52 517.64 522.24 522.43 522.99 523.03 523.41 ___ RIO BUCANA BASIN 50114000 RIO CERRILLOS NEAR PONCE, PR 377 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 mi3 (46.1 km3 ), excludes 17.4 mi3 (45.1 km3 ), upstream from Lago Cerrillos Dam. WATER-DISCHARGE RECORDS PERIOD OF RECORD.--February to April 1964 (monthly measurements only), May 1964 to June 1985, July 1985 to April 1991 (semi-monthly measurements only). May 1991 to current year. GAGE.--Water-stage recorder. Datum of gage is 253.10 ft (77.145 m), above site 0.15 mi (0.24 km) upstream and datum 9.90 ft (3.018 m) higher. san sea level. Prior to March 22, 1977 at REMARKS.--Records poor. Flow regulated by Lago Cerrillos Dam since May 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 ftVs (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 mVs), on basis of slope-area measurements of peak flow; minimum discharge prior to regulation, 2.2 ftVs (0.062 mVs), May 28, 1967. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 3.5 12 2 3.1 13 3 2.3 13 4 2.0 13 5 2.0 13 6 5.2 14 7 2.4 13 8 46 13 9 169 14 10 144 14 11 3.7 14 12 3.3 12 13 3.1 14 14 3.1 14 15 27 16 16 80 17 17 80 27 18 83 17 19 44 29 20 3.2 26 21 3.2 25 22 3.2 74 23 6.8 108 24 167 111 25 259 63 26 103 48 27 12 41 28 13 54 29 12 56 30 14 72 31 13 TOTAL 1316.1 970 MEAN 42.5 32.3 MAX 259 111 MIN 2.0 12 AC-FT 2610 1920 CFSM 2.39 1.82 IN. 2.75 2.03 17 11 15 8.8 6.4 6.2 17 73 135 49 5.5 5.4 5.4 13 5.3 11 18 12 11 27 8.9 9.9 5.4 5.7 9.5 5.1 4.9 4.9 5.2 5.1 5.0 521.6 14 16.8 4 135 4.9 .9 .9 .7 .7 .7 .6 .5 .8 .5 .5 .5 .6 .7 .7 .7 .7 .7 .5 .4 .4 .3 .2 .2 .2 .2 .2 .2 .4 .8 .4 .4 .2 52 .9 .2 1030 278 .95 .25 1.09 .29 .3 .2 .2 .2 .2 .2 .2 .2 .2 .2 .2 .2 .2 .2 .5 .3 .3 .4 .2 .5 .2 .5 .1 .5 .2 .9 .2 6.0 .2 7.4 .5 7.9 .2 7.8 .4 7.6 .4 7.6 .9 7.6 .9 7.6 .5 7.6 .2 7.6 .2 7.6 .2 7.7 .2 7.9 .2 7.9 .2 7.9 8.1 —— 8.0 —— 7.9 122.4 195.2 4.37 6.30 5.5 8.1 4.1 4.2 243 387 .25 .35 .26 .41 STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1964 - 1993 MEAN 78.3 60.8 MAX 202 124 (WY) 1971 1978 MIN 27.7 15.3 (WY) 1966 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 24.0 15.8 49.1 74.2 1966 1992 7.60 4.52 1977 1993 10.2 10.3 20.0 20.3 1969 1969 4.37 5.13 1993 1977 FOR 1992 CALENDAR YEAR 11495.84 31.4 900 .64 1.7 22800 1.76 24.03 73 14 3.1 Jan 6 Aug 19 Aug 24 7.6 7.4 7.4 7.2 6.9 6.9 6.7 6.6 6.5 6.6 6.5 6.2 6.5 6.4 6.1 6.0 6.2 6.2 6.5 6.6 6.7 6.7 6.7 7.2 7.1 7.1 7.1 7.1 8.2 10 206.9 6.90 10 6.0 410 .39 .43 9.8 12 12 20 11 35 88 126 51 176 38 7.5 7.5 113 12 7.5 8.9 57 63 7.6 89 261 74 61 111 90 314 287 152 58 48 2407.8 77.7 314 7.5 4780 4.36 5.03 45 34 4.2 6.0 129 7.0 6.8 e40 114 14 8.8 9.0 9.5 69 63 8.7 7.3 17 127 59 5.9 5.8 5.7 22 27 5.9 125 5.9 5.2 5.1 991.8 33.1 129 4.2 1970 1.86 2.07 5.2 5.3 144 17 5.1 5.2 5.4 5.3 5.4 120 45 5.6 5.2 4.9 40 37 4.7 4.7 4.4 4.2 69 69 9.3 5.3 4.6 .5 .4 .2 .1 .1 .0 656.1 21.2 144 4.0 1300 1.19 1.37 109 4.4 3.9 3.8 3.8 3.6 3.6 3.5 3.5 3.4 3.5 3.4 3.3 3.2 206 9.1 8.9 8.8 8.8 9.0 9.2 10 127 93 25 20 11 8.1 7.6 27 17 761.4 24.6 206 3.2 1510 1.38 1.59 6.0 5.5 5.5 5.5 5.6 5.8 5.7 5.8 6.0 6.1 6.2 6.5 6.6 6.7 6.9 6.9 6.9 7.2 7.5 12 16 16 14 9.5 9.7 9.3 9.8 11 54 72 --- 352.2 11.7 72 5.5 699 .66 .74 , BY WATER YEAR (WY) 17.0 106 1985 4.93 1979 FOR 1993 8641. 23. 314 2. 2. 616 5. 17140 1. 18. 72 6. 4. 42.4 221 1985 4.14 1967 WATER YEAR 7 7 May 27 0 Oct 4 9 Oct 1 May 27 74 May 27 33 06 9 2 29.8 88.9 1969 4.10 1974 26.5 71.1 1968 6.26 1976 WATER 34 53 17 11500 1 1100 6 24830 1 26 79 17 5 35.9 82.4 1968 13.2 1984 YEARS 1964 .3 .9 .2 Oct . 64 Aug .7 Aug Jan .07 Jan .93 .17 .8 64.7 256 1975 11.7 1993 - 1993 1969 1974 7 1985 19 1992 24 1992 6 1992 6 1992 e Estimated 372 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, (3.7 km) upstream from Quebrada Ausubo and 4.6 mi (7.4 km) northeast of Plaza Degetau in Ponce. DRAINAGE AREA.--17.8 mi 1 (46.1 km1 ) WATBR-QOALITY RECORDS PERIOD OF RECORD.—Water years 1964 to current year. WATER-QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 2.3 mi DATE OCT 1992 27... DEC 08. .. MAR 1993 01... APR 13 ... JUN 15... AOG 16... TIME 1215 1210 1055 1150 1415 1300 DIS- CHARGE, INST. CUBIC FEET PER SECOND 12 4.5 4.4 6.3 11 11 SPE- CIFIC CON- DUCT- ANCE (US/CM) 400 306 470 422 423 392 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.7 7.8 7.9 7.6 7.9 7.4 TEMPER- ATURE WATER (DBG C) 29.0 23.9 25.5 27.0 28.0 26.0 TUR- BID- ITY (NTO) 38 1.2 0.90 0.70 1.0 340 OXYGEN, DIS- SOLVED (MG/L) 6.1 7.9 7.1 5.7 8.5 5.2 OXYGEN, OXYGEN DIS- DEMAND, SOLVED CHEM- (PBR- ICAL CENT (HIGH SATOR- LEVEL) ATION) (MG/L) 79 12 105 <10 97 <10 71 <10 110 <10 64 16 COLI- FORM, FECAL, 0.45 UM-HF (COLS./ 100 ML) K20 42000 70 K20 4900 200 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) K70 7700 K110 K120 680 70 DATE OCT 1992 27... DEC 08... MAR 1993 01... APR 13... JUN 15... AUG 16... 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- SOLVED (MG/L SODIUM, DIS- SOLVED (MG/L SODIOM AD- SORP- TION RATIO POTAS- SIUM, DIS- SOLVED (MG/L ALKA- LINITY WAT WH TOT FET FIELD MG/L AS SOLFIDB TOTAL (MG/L SOLFATB DIS- SOLVED (MG/L CHLO- RIDE, DIS- SOLVED (MG/L AS CA) AS MG) AS NA) 440 5 150 15 30 190 10 63 140 2 42 6.9 23 9.2 27 AS K) 0.6 1.4 0.7 0.90 1 2.2 CAC03 120 100 160 150 180 140 AS S) AS SO4) AS CL) <0.5 22 <0.5 56 45 11 7.8 22 SOLIDS, RESIDUE DATE OCT 1992 27.. . DEC 08... MAR 1993 01... APR 13.. . JUN 15... AOG 16.. . FLOO- RIDB, DIS- SOLVED (MG/L AS F) 0.20 -- -- 0.30 -- 0.20 SILICA, DIS- SOLVED (MG/L AS SI02) 27 — — 26 -- 21 SUM OF CONSTI- TOENTS, DIS- SOLVED (MG/L) 578 -- -- 274 -- 253 SOLIDS, DIS- SOLVED (TONS PER DAY) 18.7 — -- 4.66 -- 7.50 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 3 2 5 1 5 596 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 11.0 0.860 0.890 0.490 0.690 0.860 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.010 0.040 0.010 0.010 0.010 0.040 NITRO- GEN, N02+N03 TOTAL (MG/L AS N) 11.0 0.900 0.900 0.500 0.700 0.900 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.020 0.050 0.010 0.030 0.070 0.050 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.48 0.35 0.29 0.47 0.63 0.35 K = non-ideal count DATS OCT 1992 27... DBC 08... MAR 1993 01... APR 13... JUN 15... AUG 16... DATE OCT 1992 27.. . DBC 08... MAR 1993 01.. . APR 13.. . JUN 15... AUG 16... RIO BOCANA BASIN 50114000 RIO CBRRILLOS NBAR PONCB, PR—Continued WATER-QUALITY DATA, WATER YBAR OCTOBER 1992 TO SBPTBMBBR 1993 373 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.50 0.40 0.30 0.50 0.60 0.40 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) 870 NITRO- GEN, TOTAL (MG/L AS N) 2.0 0.5 1.2 1.6 0.7 0.5 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) «! NITRO- GEN, TOTAL (MG/L AS NO3) 5.1 4.7 7.9 3.1 5.8 4.7 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) 60 PHOS- PHORUS TOTAL (MG/L AS P) 0.020 0.030 0.010 0.010 0.090 0.030 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) <0.10 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) 30 -- — 40 -- -- ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) <10 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) •cO.010 2 COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) 20 — — <10 — -- MBTHY- LBNB BLUB ACTIVE SUB- STANCE (MG/L) 0.05 30 40 •cO.10 •cO.010 0.02 374 RIO BUCANA BASIN 50114390 RIO BUCANA AT HWY 14 BRIDGE NEAR PONCE, PR LOCATION. —Lat 18<>02'29", long 66<>34'58", Hydrologic Onit 21010004, on left bank, 200 ft (61 m) upstream from 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 BUGana 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, 1992, afterward flow regulated by Lago Cerrillos Dam 0.4 mi upstream. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 4.3 5.6 2 3.5 5.5 3 3.3 5.6 4 2.7 5.2 5 2.7 5.2 6 6.8 5.3 7 3.6 5.4 8 5.2 5.4 9 42 5.4 10 47 5.2 11 13 5.2 12 5.9 5.2 13 5.0 5.2 14 4.3 5.0 15 5.9 6.9 16 18 7.5 17 22 9.2 18 23 8.4 19 20 6.4 20 9.9 9.6 21 5.0 8.3 22 5.4 11 23 5.1 25 24 42 29 25 93 20 26 35 15 27 12 15 28 5.7 19 29 5.6 20 30 6.1 31 31 6.5 --- TOTAL 469.5 315.7 MEAN 15.1 10.5 MAX 93 31 MIN 2.7 5.0 AC-FT 931 626 CFSM .61 .42 IN. .70 .47 19 18 17 18 11 6.3 6.7 13 27 25 12 6.5 6.3 8.6 8.2 8.1 12 13 13 17 14 13 12 11 12 11 10 10 10 10 11 389.7 12.6 27 6.3 773 .50 .58 STATISTICS OF MONTHLY MEAN DATA MEAN 182 84.2 MAX 527 222 (WY) 1991 1988 MIN 15.1 10.5 (WY) 1993 1993 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 21.6 49.1 1988 12.6 1993 FOR 11 10 10 9.9 9.8 9.8 9.8 9.5 9. 9. 9. 9. 9. 9. 9.6 9.5 9.8 9.8 9.8 9.8 9.4 9.1 8.8 8.3 8.0 7.8 7.6 8.5 14 9.7 7.8 293.5 9.47 14 7.6 582 .38 .44 7.3 7.1 7.3 6.5 6.1 5.7 5.6 5.8 6.0 6.0 5.2 5.0 4.8 4.7 4.5 5.3 5.1 4.6 5.7 6.9 5.4 5.0 4.9 4.7 4.8 5.0 5.0 5.0 ___ ___ 155.0 5.54 7.3 4.5 307 .22 .23 FOR WATER YEARS 1987 67.3 337 1992 9.47 1993 10.4 17.3 1992 5.54 1993 5.6 5.7 5.8 5.8 5.4 5.2 5.3 5.4 5.4 5.4 5.5 5.8 6.0 5.9 6.1 6.3 6.2 6.6 6.6 6.6 6.0 5.8 5.8 5.9 5.9 5.6 5.3 6.6 5.9 5.8 5.7 180.9 5.84 6.6 5.2 359 .23 .27 - 1993 16.0 48.0 1989 5.81 1990 1992 CALENDAR YEAR 19239.2 52.6 4340 2.5 2.8 38160 2.11 28.74 55 14 5.2 Jan 6 Sep 28 Sep 23 5.6 5.8 5.9 6.1 5.2 4.7 5.0 5.2 6.3 4.5 3.8 4.5 7.5 6.3 4.7 4.6 4.8 5.6 5.4 7.5 4.8 4.7 4.8 8.2 5.7 5.7 6.1 6.5 8.0 13 --- 176.5 5.88 13 3.8 350 .24 .26 15 11 10 11 11 10 21 48 27 98 61 15 12 39 43 7.6 7.5 8.5 63 15 20 214 79 64 120 48 297 320 185 38 86 2004.6 64.7 320 7.5 3980 2.60 2.99 21 68 18 8.8 69 26 13 10 66 56 22 15 13 17 81 26 16 14 83 98 28 19 16 25 26 19 84 35 19 15 --- 1026.8 34.2 98 8.8 2040 1.37 1.53 14 14 91 73 24 17 16 15 15 62 100 31 20 16 18 54 28 19 16 14 21 66 47 18 11 10 10 9.7 9.6 9.7 9.9 878.9 28.4 100 9.6 1740 1.14 1.31 96 39 10 9.5 9.6 9.5 9.1 9.1 9.1 8.9 9.5 9.3 9.1 9.3 331 55 23 11 11 9.9 9.3 13 86 169 33 21 22 10 8.7 14 22 1095.9 35.4 331 8.7 2170 1.42 1.64 8.8 7.2 5.0 5.0 5.0 5.2 5.2 5.2 6.0 5.1 .9 .7 .7 .7 .7 .9 .9 5.5 5.9 6.4 6.6 6.5 7.2 7.2 6.5 6.4 6.4 6.9 11 40 --- 213.7 7.12 40 4.7 424 .29 .32 , BY HATER YEAR (WY) 18.8 42.5 1992 5.88 1993 FOR 1993 7200. 19. 331 2. 3. 1010 10. 14280 10. 42 9. 5. 35.8 94.9 1992 5.89 1990 WATER YEAR 7 7 Aug 15 7 Oct 4 8 Oct 1 Aug 15 13 Aug 15 79 76 3 0 35.9 80.5 1989 8.09 1990 25.6 51.4 1991 6.08 1990 HATER 55 78 19 4340 2 2 17400 13 39920 2 30 98 14 5 58.5 169 1988 16.8 1992 YEARS 1987 .1 .0 .7 Jan .5 Sep .8 Sep Oct .48 Oct .21 .07 .8 85.3 265 1989 7.12 1993 - 1993 1991 1993 6 1992 28 1992 23 1992 7 1985 7 1985 RIO PORTUGUES BASIN 50115000 RIO PORTUGUES NEAR PONCE, PR 375 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 1 (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 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 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 17 29 2 15 27 3 13 28 4 41 23 5 e68 20 6 e!98 20 7 e!74 19 8 e!26 18 9 e!26 16 10 232 15 11 129 13 12 65 86 13 36 57 14 72 31 15 e!20 37 16 87 65 17 131 81 18 91 44 19 55 34 20 45 e72 21 38 e49 22 33 34 23 127 28 24 elSO 25 25 e!26 22 26 45 20 27 31 21 28 26 36 29 41 36 30 36 24 31 36 —— TOTAL 2530 1030 MEAN 81.6 34.3 MAX 232 86 HEN 13 13 AC-PT 5020 2040 CFSM 9.25 3.89 IN. 10.67 4.34 STATISTICS OF MONTHLY MEAN MEAN 44.8 33.6 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 (CFSH) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 19 18 17 16 15 15 14 14 14 16 e!3 e!3 e!4 e!6 e!4 ell elO 12 12 12 12 12 12 12 12 14 13 11 e29 e!8 elO 440 14.2 29 10 873 1.61 1.86 DATA 12.6 27.3 1988 2.71 1992 FOR 8.4 8.2 8.1 8.1 8.8 8.6 7.4 7.4 7.7 6.8 6.2 6.2 6.4 6.9 7.4 7.3 7.1 7.1 7.1 7.1 7.0 6.9 7.1 6.2 6.2 6.1 6.0 40 172 39 19 463.8 15.0 172 6.0 920 1.70 1.96 11 8.9 10 7.3 6.7 6.5 6.2 6.2 6.1 5.9 5.8 5.7 5.7 5.3 5.1 20 11 6.8 8.0 8.9 6.6 6.0 6.1 6.0 5.6 5.8 5.9 6.1 ___ ___ --- 205.2 7.33 20 5.1 407 .83 .87 FOR WATER YEARS 1964 9.02 45.5 1992 3.65 1989 6.17 13.3 1976 2.62 1989 6.2 6.5 6.2 5.9 5.4 5.3 5.3 5.3 5.5 5.6 5.3 5.4 5.6 5.9 6.4 5.9 5.3 5.3 .8 .8 .8 .8 .6 5.4 7.2 6.4 5.3 5.4 5.1 5.2 5.1 171.2 5.52 7.2 4.6 340 .63 .72 - 1993 5.73 13.4 1976 2.08 1977 1992 CALENDAR YEAR 8552.5 23.4 794 2.0 3.1 16960 2.65 36.07 45 10 3.8 Jan 6 Jan 4 Apr 29 4.7 4.7 6.8 5.3 5.2 5.3 5.3 8.8 10 6.6 17 23 32 18 29 26 15 12 12 10 11 11 11 16 15 11 e!3 e39 e!36 137 656.7 21.9 137 4.7 1300 2.48 2.77 90 110 105 68 36 29 28 27 62 36 23 19 16 20 14 12 11 9.7 8.5 11 77 17 12 14 11 85 225 93 37 29 33 1368.2 44.1 225 8.5 2710 5.00 5.77 e21 e!9 e!8 e!7 e!7 e!5 e!6 e96 e99 23 16 15 13 13 20 18 13 12 40 39 21 19 17 15 13 15 16 18 16 15 705 23.5 99 12 1400 2.66 2.97 15 15 24 18 24 19 16 19 17 15 47 18 15 17 12 11 11 11 11 11 12 14 12 12 9.4 7.5 7.3 7.3 7.2 7.9 7.8 450.4 14.5 47 7.2 893 1.65 1.90 8.3 8.8 9.4 10 11 11 11 10 10 11 10 9.8 8.6 8.5 9.6 53 11 12 11 11 12 31 20 13 11 10 41 13 7.8 7.7 10 421.5 13.6 53 7.7 836 1.54 1.78 10 13 9.5 8.5 8.5 9.6 8.0 9.8 9.1 36 8.0 7.0 9.2 8.0 6.4 7.6 7.3 6.7 6.4 24 11 14 19 13 8.7 15 12 23 22 107 --- 457.3 15.2 107 6.4 907 1.73 1.93 , BY WATER YEAR (WY) 7.59 27.1 1983 2.45 1974 FOR 1993 8899. 24. 232 4. 4. 2850 9. 17650 2. 37. 56 12 5. 20.2 72.9 1985 1.65 1973 WATER YEAR 3 4 Oct 10 6 Mar 23 9 Mar 17 May 27 58 May 27 76 53 9 15.2 48.3 1979 2.33 1974 14.6 54.2 1979 2.65 1976 WATER 18 38 8 2440 1 1 21000 20 1 13550 2 28 40 8 3 20.5 87.5 1979 4.20 1972 YEARS 1964 - .7 .0 .04 Sep 16 .1 May 29 .3 May 23 Oct 7 .20 Oct 7 .0 May 29 .12 .80 .4 .1 34.7 132 1975 7.22 1991 1993 1979 1974 1975 1973 1973 1985 1985 1973 e Estimated *** » RIO PORTUODBS BASIN 50115000 RIO PORTUGUBS NEAR PONCE, PR—Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1964 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 26... DEC 09... MAR 1993 02... APR 14... JUN 16... AUG 17... TIME 1415 1000 1130 1220 1300 1225 DIS- CHARGE, INST. CUBIC FEET PER SECOND 36 14 6.4 18 16 12 SPE- CIFIC CON- DUCT- ANCE (US/CM) 252 324 310 273 247 262 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.6 8.2 8.1 7.4 8.1 7.0 TEMPER- ATURE WATER (DBG C) 24.5 20.9 21.5 23.5 27.5 26.5 TUR- BID- ITY (NTU) 49 13 0.40 330 0.50 6.2 OXYGEN, DIS- SOLVED (MG/L) 5.0 8.5 9.1 5.7 8.1 5.4 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 60 104 110 68 100 65 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) < 10 < 10 <10 36 14 12 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 760 230 K170 K1500 570 230 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 480 K170 K70 K1400 380 K150 DATE OCT 1992 26... DEC 09... MAR 1993 02... APR 14... JUN 16. .. AUG 17... HARD- NESS TOTAL (MG/L HARD- NESS NONCARB WH WAT TOT FLD CALCIUM DIS- SOLVED MAGNE- SIUM, DIS- SOLVED SODIUM, DIS- SOLVED SODIUM AD- SORP- TION POTAS- SIUM, DIS- SOLVED AIJKA- LINITY WAT WH TOT FB1 FIELD AS MG/L AS (MG/L CAC03) CAC03 120 0 38 69 0 19 200 1 53 (MG/L (MG/L AS CA) AS MG) AS NA) 5.8 8.2 5.3 11 16 34 RATIO AS K) 0.3 1.2 0.6 3.0 1 4.0 CAC03 140 140 140 97 130 60 CHLO- SULFATB RIDE, SULFIDB DIS- DIS- TOTAL SOLVED SOLVED (MG/L MG/L AS (MG/L (MG/L <0.5 7.4 <0.5 16 33 (MG/L AS S) AS S04) AS CL) 6.7 11 34 SOLIDS, RESIDUE DATE OCT 1992 26... DEC 09... MAR 1993 02... APR 14... JUN 16... AUG 17... FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.10 -- -- <0.10 -- 0.20 SILICA, DIS- SOLVED (MG/L AS SI 02) 23 -- -- 20 -- 31 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 174 -- -- 143 -- 241 SOLIDS, DIS- SOLVED (TONS PER DAY) 16.9 -- -- 7.13 __ 7.81 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 12 <1 <1 1000 24 4 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 1.30 0.590 1.09 0.990 0.890 0.590 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) 1.30 1.10 1.10 1.00 0.900 0.600 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.010 0.010 0.010 0.010 0.010 0.030 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.19 0.29 0.29 0.59 0.29 0.27 K • non-ideal count 377 DATE OCT 1992 26... DEC 09.. . MAR 1993 02... APR 14.. . JUN 16... AUG 17... DATE OCT 1992 26... DEC 09.. . MAR 1993 02... APR 14.. . JUN 16... AUG 17... RIO PORTOGDBS BASIN 50115000 RIO PORTUGUBS NEAR PONCE, PR—Continued WATER-QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.20 0.30 0.30 0.60 0.30 0.20 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) 1.6 1.9 1.3 1.5 1.3 1.6 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N03) 5.4 7.8 5.8 6.6 5.3 6.1 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.040 0.190 0.040 0.050 0.050 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 — — 200 — -- 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 -- -- 14 — -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) <10 — — 60 — — MBTHY- LSNB BLUB ACTIVE SUB- STANCE (MG/L) 890 14000 11 430 740 <0.10 <0.10 40 <0.010 60 <0.010 0.02 0.03 378 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 m) south of Las Americas Avenue Bridge, 1.2 ml (1.9 km) south of CSC 50115900, 0.8 ml (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 1 (49.0 km 9 ). PERIOD OF RECORD. — Water years 1979 to current year. HATER- QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE DIS- CHARGE INST. CUBIC FEET TIME PBR PH OXYGEN, OXYGEN COLI- SPB- WATER DIS- DEMAND, FORM, STRBP- CIFIC WHOLE SOLVED CHEM- FECAL, TOCOCCI CON- FIELD TEMPER- TOR- OXYGEN, (PBR- ICAL 0.45 FECAL, DUCT- (STAND- ATURB BID- DIS- CENT (HIGH UM-MF (COLS. ANCB ARD WATER ITY SOLVED SATUR- LEVEL) (COLS./ PBR SECOND (US/CM) UNITS) (DBG C) (NTU) (MG/L) ATI ON) (MG/L) 100 ML) 100 ML) OCT 1992 28... DBC 09. .. MAR 1993 02... APR 14. .. JUN 24... AUG 17... 1335 4.6 1125 5.6 1240 10 1350 40 1330 16 1400 23 HARD- HARD- NESS 297 7.8 30.0 10 5.3 70 <10 K1400 K160 418 7.9 24.2 12 9.6 110 <10 4900 440 475 7.8 26.0 15 7.3 88 17 K7300 K890 365 7.5 30.5 240 5.3 70 15 27000 5400 340 7.7 32.5 4.1 6.1 74 34 4400 21000 395 7.5 32.5 22 6.1 79 <10 21000 3800 ALKA- HAGNB- SODIUM POTAS- LINITY CHLO- NESS NONCARB CALCIUM SIUM, SODIUM, AD- SIUM, WAT WH SULFATB RIDE, TOTAL WH WAT DIS- DIS- DIS- SORP- DIS- TOT FET SULFIDE DIS- DIS- (MG/L TOT FLD SOLVED SOLVED SOLVED TION SOLVED FIELD TOTAL SOLVED SOLVED DATE OCT 1992 28... DBC 09... MAR 1993 02. .. APR 14... JUN 24... AUG 17... AS MG/L AS (MG/L (MG/L (MG/L RATIO (MG/L MG/L AS (MG/L (MG/L (MG/L CACO3) CACO3 110 0 __ — 120 3 _- 180 17 AS CA) AS MG) AS NA) AS K) CACO3 AS S) AS SO4 ) AS CL) 33 6.1 14 0.2 2.4 120 <O.S 23 36 130 130 35 6.7 16 0.6 1.7 110 <0.5 19 14 180 61 6.7 18 0.6 0.90 160 -- 45 7.0 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- OCT 28 DBC 09 MAR 02 APR 14 JUN 24 AUG 17 RIDE, DIS- SOLVED DATE (MG/L AS F) 1992 0.10 1993 0.10 0.20 DIS- CONSTI- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, SOLVED TUENTS, SOLVED DBG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC (MG/L DIS- (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL AS SOLVED PER PBNDED (MG/L (MG/L (MG/L (MG/L (MG/L SIO2) (MG/L) DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) 21 320 3.97 <1 0.940 0.010 0.950 0.030 0.27 26 0.660 0.040 0.700 0.090 0.31 26 0.900 0.100 1.00 0.260 0.44 20 178 19.5 740 1.08 0.020 1.10 0.410 0.19 20 0.580 0.020 0.600 0.060 0.84 22 257 15.9 22 0.470 0.030 0.500 0.110 2.2 K - non-ideal count DATE OCT 1992 28... DEC 09... MAR 1993 02... APR 14.. . JUN 24... AUG 17... RIO PORTUGUBS BASIN 50116200 RIO PORTUGUBS AT PONCE, PR—Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 379 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 CU) 0.30 0.40 0.70 0.60 0.90 2.3 1.2 1.1 0.50 1.5 1.3 2.8 5.5 4.8 1.7 1.3 6.6 12 0.130 0.150 0.100 0.160 0.080 0.060 <1 <1 <100 <100 40 <1 <1 20 DATE OCT 1992 28.. . DEC 09... MAR 1993 02... APR 14... JUN 16.. . AUG 17.. . 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) METHY- LENE BLUB ACTIVE SUB- STANCE (MG/L) 21000 11000 700 530 <0.10 <0.10 <1 <1 <1 <1 <0.010 50 <0.010 <1 0.06 0.02 PESTICIDE ANALYSES DATE JUL 1993 01... TIME 1145 PCB, TOTAL (UG/L) CHLOR- ALDRIN, DANE, TOTAL (UG/L) <0.010 TOTAL (UG/L) DDD, TOTAL (UG/L) DDE, TOTAL (UG/L) TOTAL (UG/L) <0.010 <0.010 <0.010 DI- DI- TOTAL (UG/L) TOTAL (UG/L) ENDO- DDT, AZINON, BLDRIN SULFAN, TOTAL (UG/L) <0.01 <0.010 <0.010 DATE JUL 1993 01... ENDRIN WATER UNFLTRD BTHION, REC TOTAL (UG/L) (UG/L) HEPTA- HBPTA- CHLOR CHLOR, BPOXIDB LINDANE TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) •cO.010 •cO.Ol < 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 HIREX, TOTAL (UG/L) •cO.Ol DATE JUL 1993 01... PARA- THION, TOTAL (UG/L) NAPH- THA- LENES, POLY- CHLOR. TOTAL (UG/L) PER- THANE 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 •cO.Ol <0.01 380 RIO GUAYANILLA BASIN 50124200 RIO GUAYANILLA NEAR GUAYANILLA, PR LOCATION.--Lat 18°02'40", long 66<>47'53 > , Hydrologic Unit 21010004, on left bank, 0.7 ml (1.1 km) north of junction of Highways 2 and 132, 0.6 mi (1.0 km) downstream from Quebrada Consejo, 1.8 mi (2.9 km) north-northwest from Plaza de Quayanilla. DRAINAGE AREA.--18.9 mi* (49.0 km*). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--March 1981 to current year. GAGE.—Water-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, satellite telemetry at station. Gage-height and precipitation DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 103 48 2 65 46 3 24 55 4 20 39 5 99 34 6 299 31 7 208 29 8 149 25 9 231 23 10 286 22 11 184 20 12 89 68 13 67 136 14 76 91 15 129 82 16 121 84 17 88 186 18 71 173 19 59 98 20 61 86 21 49 69 22 50 55 23 65 48 24 137 42 25 125 37 26 78 34 27 62 41 28 53 38 29 69 65 30 83 66 31 61 TOTAL 3261 1871 MEAN 105 62.4 MAX 299 186 MIN 20 20 AC-FT 6470 3710 CFSM 5.57 3.30 IN. 6.42 3.68 STATISTICS OF MONTHLY MEAN MEAN 68.1 54.0 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 46 35 30 29 25 24 22 20 18 17 16 15 32 61 50 27 22 19 17 16 16 15 14 14 13 18 16 13 12 15 46 733 23.6 61 12 1450 1.25 1.44 DATA 20.4 41.9 1988 11.9 1989 FOR 18 14 14 13 12 12 12 12 11 11 11 11 11 11 11 11 11 11 11 11 11 11 12 9.2 9.1 8.6 7.6 19 73 27 17 443.5 14.3 73 7.6 880 .76 .87 15 12 15 11 9.6 8.9 8.5 7.6 6.8 6.8 6.7 6.3 6.3 6.2 8.5 28 18 7.1 18 11 4.8 4.0 3.9 17 19 6.2 5.2 4.3 ___ ___ --- 281.7 10.1 28 3.9 559 .53 .55 FOR WATER YEARS 1981 11.3 27.5 1992 6.97 1991 7.41 11.4 1985 3.10 1990 4.5 5.0 4.9 4.6 4.6 4.9 5.0 4.6 4.8 4.6 4.2 3.9 4.0 4.0 4.3 4.2 3.8 3.9 3.7 3.9 3.7 3.6 7.1 6.6 4.4 .3 .3 .4 .0 .0 3.8 137.6 4.44 7.1 3.6 273 .23 .27 - 1993 6.06 13.2 1989 2.85 1981 1992 CALENDAR YEAR 11551.8 31.6 408 3.2 3.4 22910 1.67 22.74 70 15 4.9 Jan 6 Mar 16 Mar 13 3.2 3.0 2.9 3.0 3.1 3.1 3.3 3.1 16 11 6.5 14 10 8.8 13 28 8.2 5.2 17 13 12 7.8 5.8 5.0 4.5 3.8 3.4 39 60 187--- 503.7 16.8 187 2.9 999 .89 .99 123 142 169 162 68 39 32 23 218 109 47 30 22 20 16 21 16 11 9.9 13 13 13 9.6 27 35 79 195 106 41 30 23 1862.5 60.1 218 9.6 3690 3.18 3.67 20 17 15 13 11 9.2 9.2 33 28 21 15 13 19 14 16 17 12 63 157 97 44 31 24 19 17 15 e!3 e!8 32 27--- 839.4 28.0 157 9.2 1660 1.48 1.65 23 21 23 22 25 36 33 28 21 17 19 23 17 27 17 15 14 11 10 10 8.5 8.0 12 8.7 9.5 8.6 7.7 8.5 7.6 6.8 6.3 504.2 16.3 36 6.3 1000 .86 .99 6.3 5.4 5.4 5.2 7.0 6.3 5.5 4.6 4.6 4.6 4.7 5.3 4.5 4.1 7.9 66 22 10 7.8 6.9 6.3 97 103 35 18 13 23 55 47 50 21 662.4 21.4 103 4.1 1310 1.13 1.30 15 24 18 11 12 7.9 8.4 27 39 16 17 8.4 8.6 12 7.1 30 27 13 8.9 9.8 12 7.0 105 38 18 130 80 50 33 42 835.1 27.8 130 7.0 1660 1.47 1.64 , BY WATER YEAR (WY) 11.2 26.6 1983 4.39 1984 FOR 1993 11935 32 299 2 3 1190 10 23670 1 23 83 16 4 31.1 80.4 1985 5.83 1988 WATER YEAR .1 .7 Oct 6 .9 Apr 3 . 1 Apr 2 Sep 26 .13 Sep 26 .73 .49 .6 15.9 41.0 1987 3.28 1991 12.5 25.9 1986 5.22 1990 WATER 24 33 16 1500 1 14700 20 17690 1 17 53 10 3 18.7 48.5 1988 6.72 1985 YEARS 1981 .4 .1 .3 Oct . 97 Aug .7 Aug Sep .40 Sep .29 .55 .9 40.9 102 1981 7.46 1983 - 1993 1986 1983 7 1985 21 1990 15 1990 12 1982 12 1982 e Estimated RIO GUAYANILLA BASIN 50124700 RIO GUAYANILLA AT CENTRAL ROFINA, PR WATBR-QOALITY RECORDS LOCATION.—Lat 18°00'40", long 66°46'49", at dirt road bridge, 0.7 mi (1.1 km) from mouth, 0 Central Rufina and 0.9 ml (1.4 km) southeast of Quayanilla. DRAINAGE AREA.—22.8 mi" (59.1 km'). PERIOD OF RECORD.—Water years 1960-65, 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 357 9 mi (1.4 km) east of DATE OCT 1992 29... DEC 10... FBB 1993 19. .. APR 21... JUN 24. .. AUG 18. .. TIME 1210 1105 1230 1550 1220 1200 DIS- CHARGE, INST. CUBIC FEET PER SECOND 9.3 11 4.3 3.7 15 4.0 SPE- CIFIC CON- DUCT- ANCE (US/CM) 405 430 528 516 316 490 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.7 8.2 7.8 7.6 7.6 7.3 TEMPER- ATURE WATER (DBG C) 29.0 25.0 27.0 32.0 32.0 30.5 TUR- BID- ITY (NTU) 2.1 3.6 5.6 4.5 0.40 4.8 OXYGEN, DIS- SOLVED (MG/L) 5.8 8.2 9.4 4.1 5.3 5.0 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 74 91 108 54 69 65 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) <10 <10 21 12 22 <10 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K1000 10 K10 K30 10 10 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) K100 10 K10 50 10 10 DATE OCT 1992 29... DEC 10. .. FBB 1993 19... APR 21... JUN 24... AUG 18. .. HARD- NESS TOTAL (MG/L AS HARD- NESS NONCARB CALCIUM WH WAT TOT PLD 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 20 44 11 18 170 17 42 15 21 180 5 50 14 25 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 4.0 0.7 2.4 0.8 2.0 CACO3 160 170 160 130 150 130 CHLO- SULFATB RIDE, DIS- DIS- SOLVED SOLVED (MG/L <O.S 40 <0.5 41 48 (MG/L AS S) AS S04) AS CL) 18 20 22 SOLIDS, RESIDUE DATE OCT 1992 29.. . DEC 10.. . FEB 1993 19... APR 21... JUN 24... AUG 18... FLUO- RIDB, DIS- SOLVED (MG/L AS F) <0.10 -- -- 0.10 -- 0.10 SILICA, DIS- SOLVED (MG/L AS SIO2) 22 -- -- 19 -- 20 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 219 -- -- 238 -- 259 SOLIDS, DIS- SOLVED (TONS PER DAY) 5.50 -- -- 2.38 — 2.80 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) <1 23 4 20 9 15 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 1.38 0.780 1.28 0.570 1.47 1.28 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.020 0.020 0.020 0.030 0.030 0.020 NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 1.40 0.800 1.30 0.600 1.50 1.30 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.020 0.580 0.250 0.780 1.10 0.250 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.38 0.22 0.75 0.92 1.1 0.75 non-ideal count 382 DATS OCT 1992 29... DEC 10... FEE 1993 19... APR 21... JDN 24... AUG 18... RIO GUAYANILLA BASIN 50124700 RIO GUAYANILLA AT CENTRAL RUPINA, PR--Continued HATER-QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 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) 0.40 0.80 1.0 1.7 2.2 1.0 AS N) AS N03) AS P) AS AS) AS BA) AS B) AS CD) AS CR) AS CU) 1.8 1.6 2.3 3.7 4.2 2.5 8.0 18 10 16 12 9 0.240 0.370 0.740 0.660 0.220 0.600 <100 30 <1 <1 1 <100 50 <1 <1 DATE OCT 1992 29... DEC 10... FEE 1993 19... APR 21... JUN 24... AUG 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 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 BLUE ACTIVE SUB- STANCE (MG/L) 1900 430 70 50 <0.10 <0.10 <1 <1 <1 <1 30 20 <0.010 <0.010 0.05 0.09 PESTICIDE ANALYSES DATE OUL 1993 01... CHLOR- PCB, ALDRIN, DANE, TIME TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) 1250 <0.1 <0.010 DDD, TOTAL (UG/L) DDE, TOTAL (UG/L) DDT, TOTAL (UG/L) <0.010 <0.010 <0.010 DI- AZINON, TOTAL (UG/L) DI- ENDO- BLDRIN SULFAN, TOTAL TOTAL (UG/L) (UG/L) 0.03 <0.010 <0.010 DATE OUL 1993 01... ENDRIN HATER UNFLTRD BTHION, REC (UG/L) TOTAL (UG/L) HEPTA- HBPTA- 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) <0.01 MBTH- OXY- CHLOR, TOTAL (UG/L) <0.01 METHYL PARA- THION, TOTAL (UG/L) <0.01 MIRBX, TOTAL (UG/L) <0.01 DATE JUL 1993 01.. . 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) SILVEX, TOTAL (UG/L) <0.01 <0.10 <1 <0.01 <0.01 <0.01 <0.01 <0.01 RIO YAUCO BASIN 50125780 LAGO LUCCHETTI AT DAMSITB, PR 383 LOCATION.--Lat 18°05'37", long 66°51'54' (6.3 km) north of Yauco. DRAINAQB AREA.--17.4 ml 9 (45.1 km'). Hydrologic Unit 21010004, at Antonio Lucchetti Dam on Rio Yauco, 3.9 ml ELEVATION RECORDS PERIOD OF RECORD.--December 1989 to current year. GAGE.--Water-stage recorder. Datum of gage is mean sea level. REMARKS.—Lago Lucchetti was completed in 1952. The dam is on Rio Yauco and is a unit of the Southwestern Puerto Rico Project. It provides 16,500 acre-feet (20.3 hm1 ) of usable storage for power generation and irrigation. The dam is 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 mj/s) 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, 572.19 ft (174.40 m), May 27, 1993; minimum elevation, 519.85 ft (158.45 m), Oct. 23, 1991. EXTREMES OBSERVED FOR CURRENT YEAR.--Maximum elevation, 572.19 ft (174.40 m), May 27 j minimum elevation, 530.07 ft (161.56 m), Aug. 6. Capacity Table (based on data from Puerto Rico Water 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 Contents, in acre-feet 540 550 561 563 571 573 5,165 7,020 9,600 10,125 12,125 12,645 ELEVATION (FEET NGVD), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY OBSERVATION AT 24:00 VALUES DAY OCT 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 A A A A A 536.13 538.07 539.55 539.53 541.40 542.64 543.60 544.35 544.51 544.71 546.23 547.14 A A A 21 22 23 24 25 26 27 28 29 30 31 TOTAL MEAN MAX MIN NOV A A A A 568.94 568.08 569.96 570.46 570.04 569.24 568.26 568.62 569.83 570.41 570.90 570.25 570.32 571.08 570.13 570.21 570.35 570.44 569.88 568.54 566.02 DEC 556.84 556.95 557.87 559.34 560.75 562.14 563.52 563.25 563.59 564.82 566.05 567.16 568.48 569.69 569.93 570.16 570.27 570.19 570.19 569.94 568.84 568.30 566.91 565.30 565.33 JAN 563.38 563.37 563.36 563.34 562.44 562.45 562.01 562.02 562.01 562.01 562.01 560.46 560.45 559.66 559.64 558.04 557.66 556.71 556.23 555.37 555.09 555.09 555.07 555.04 554.99 FBB 556.28 557.46 557.83 559.50 561.13 562.58 564.05 564.54 563.55 562.77 562.89 563.32 563.30 563.31 565.01 565.15 564.32 563.67 563.07 563.41 563.44 563.50 563.45 563.49 563.44 MAR 562.96 563.39 563.08 563.84 563.84 564.15 564.13 564.11 564.08 564.07 564.13 563.86 563.80 563.80 563.09 563.31 563.27 563.24 563.21 563.17 563.13 563.10 563.07 563.05 563.03 APR 561.61 561.56 561.51 561.48 560.59 560.54 559.07 559.09 559.08 559.04 559.20 559.42 559.87 560.02 560.72 561.94 562.20 562.45 562.21 562.60 562.06 562.61 563.25 563.76 563.75 MAY 570.75 570.79 570.69 570.33 569.45 568.68 569.42 569.19 570.57 569.89 568.70 569.17 569.93 569.77 569.82 569.43 570.58 570.29 570.28 570.00 569.00 569.29 569.85 569.71 569.39 JUN 566.51 566.20 566.05 565.75 565.26 565.31 564.31 563.99 564.85 564.82 565.48 566.48 565.93 566.41 566.35 566.25 565.41 565.27 565.25 562.91 561.51 560.03 557.90 555.54 553.54 563.70 560.98 558.17 557.35 556.24 564.16 564.22 563.21 563.25 563.26 563.38 554.08 553.80 553.85 555.78 555.75 556.23 563.19 563.07 563.02 ___ 562.99 563.06 563.08 562.08 562.05 562.02 563.73 564.60 565.16 565.52 569.15 570.19 571.18 569.95 568.87 567.69 566.81 552.28 552.23 552.38 552.54 552.63 JUL 552.15 551.96 552.03 552.08 551.91 552.24 552.58 552.63 552.57 552.20 550.43 550.35 550.22 550.58 549.91 547.87 545.81 543.89 543.85 544.55 543.38 541.97 539.72 537.61 534.26 A A A A A A AUG A A A 530.28 530.22 530.23 530.70 A A A 535.72 536.76 A A 538.45 A 539.30 A A 540.87 541.37 542.41 542.68 542.68 542.68 542.73 543.10 543.28 543.42 543.70 543.80 SEP 543.89 544.14 544.14 544.14 544.14 544.08 544.08 544.08 544.08 545.34 546.92 547.12 547.15 547.43 547.50 A A A A A A 551.73 553.82 554.21 555.93 558.20 564.04 566.09 567.25 567.10 —— 17517.29 17317.39 15753.74 17463.19 16857.79 17659.66 16859.37 565.07 570.27 556.84 558.63 563.38 553.80 562.63 565.15 556.28 563.33 564.15 562.02 561.93 569.15 559.04 569.67 561.98 571.18 566.51 566.81 552.23 A No gage-height record. 384 RIO LOCO BASIN 50129700 RIO LOCO AT GUANICA, PR WATER-QUALITY RECORDS LOCATION.--Lat 17°58'33", long 66°54'52", 0.6 mi (1.0 km) northwest of Guanica and 1.2 mi (1.9 km) northeast of Ensenada. DRAINAGE AREA.--Indeterminate. PERIOD OF RECORD.--Water years 1975 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 28... DEC 10... FBB 1993 17... APR 19... JUN 02... ADG 18... TIME 1130 1145 1145 1330 1330 1315 DIS- CHARGE, SPB- INST. CIFIC CUBIC CON- FEET DUCT- PBR ANCB SECOND (US/CM) 446 600 510 564 506 12400 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.4 7.9 7.9 7.4 7.9 7.1 TEMPER- ATURE WATER (DBG C) 26.5 24.8 24.0 28.0 29.0 29.0 TUR- BID- ITY (NTU) 8.3 23 4.9 50 12 18 OXYGEN, DIS- SOLVED (MG/L) 3.0 4.5 4.9 2.9 1.0 2.0 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 43 54 59 37 21 27 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) <10 <10 <10 29 42 34 COLI- FORM, FECAL, 0.45 OM-MP (COLS./ 100 ML) 520 490 1000 510 4800 2800 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 850 360 490 430 6700 2400 DATE OCT 1992 28... DEC 10... FEB 1993 17... APR 19... JUN 02. .. AUG 18. .. HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL Vffl WAT DIS- (MG/L TOT FLD SOLVED AS MG/L AS (MG/L CAC03) CAC03 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS NA) 970 3 22 18 14 140 0 29 16 36 170 2 28 25 13 ALKA- SODIUM POTAS- LINITY AD- SIUM, WAT Vffl SORP- DIS- TOT FET SULFIDB TION SOLVED FIELD TOTAL RATIO (MG/L MG/L AS (MG/L AS K) 3.5 1 3.8 0.4 3.8 CACO3 170 180 170 140 180 150 CHLO- SULFATB RIDB, DIS- DIS- SOLVED SOLVED (MG/L <0.5 42 <0.5 23 27 (MG/L AS S) AS S04) AS CL) 60 58 19 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- DATE OCT 1992 28... DEC 10... FEB 1993 17... APR 19... JUN 02... AUG 18.. . RIDB, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS AS F) SI02) 1.1 28 __ __ 0.10 23 __ 0.20 28 CONSTI- DIS- TUENTS, SOLVED DIS- (TONS SOLVED PER (MG/L) DAY) 492 -- __ 273 __ 234 AT 105 DBG. C, SUS- PENDED (MG/L) 30 12 7 82 58 40 GEN, NITRATE TOTAL (MG/L AS N) 0.500 -- -- 0.076 0.087 -- GEN, NITRITE TOTAL (MG/L AS N) 0.030 <0.010 •eO.010 0.010 0.010 <0.010 GEN, NO2+NO3 TOTAL (MG/L AS N) 0.530 0.057 0.082 0.086 0.097 0.098 GBN, AMMONIA TOTAL (MG/L AS N) 0.060 0.030 0.090 0.040 0.060 0.050 GEN, ORGANIC TOTAL (MG/L AS N) 0.44 0.27 0.31 0.26 0.84 0.25 RIO LOCO BASIN 50129700 RIO LOCO AT GUANICA, PR—Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 385 DATS OCT 1992 28... DBC 10... FBB 1993 17... APR 19... JUN 02.. . AUG 18... NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.50 0.30 0.40 0.30 0.90 0.30 NITRO- NITRO- PHOS- GEN, GEN, PHORUS ARSENIC TOTAL TOTAL TOTAL TOTAL (MG/L (MG/L (MG/L '.UG/L AS N) AS N03) AS P) 1.0 0.36 0.48 0.39 1.0 0.40 4.6 1.6 2.1 1.7 4.4 1.8 0.270 0.060 0.150 0.030 0.270 0.100 BARIUM, TOTAL RECOV- ERABLE (UG/L <100 <100 BORON, CADMIUM TOTAL TOTAL RBCOV- RECOV- ERABLE BRABLB (UG/L (UG/L AS AS) AS BA) AS B) 40 70 AS CD) CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) <10 10 DATE OCT 1992 28.. . DEC 10.. . FBB 1993 17... APR 19... JUN 02.. . AUG 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 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) 860 930 <1 140 100 <0.10 <0.10 <1 <1 <1 <1 <10 <0.010 <10 <0.010 <1 0.32 0.03 PESTICIDE ANALYSES DATE JUN 1993 26... 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) <0.010 <0.010 <0.010 DI- AZINON, TOTAL (UG/L) DI- BNDO- BLDRIN SULFAN, TOTAL TOTAL (UG/L) (UG/L) <0.01 <0.010 <0.010 DATE JUN 1993 26... ENDRIN WATER UNPLTRD BTHION, RBC (UG/L) TOTAL (UG/L) HEPTA- HBPTA- CHLOR CHLOR, BPOXIDB LINDANE TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) <0.010 <0.01 <0.010 <0.010 <0.010 HALA- 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 JUN 1993 26... 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) 0.11 2,4,5-T 2, 4-DP SILVBX, TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) <0.01 <0.01 <0.01 386 THIS PAGE WAS LEFT BLANK INTENTIONALLY 0123456 KILOMETERS f-__ ,..: ...!.._ ^ 01234 MILES op oreo EXPLANATION A 138° SURFACE-WATER STATION AND NUMBER T 1297 QUALITY-OF-WATER STATION AND NUMBER us WELL AND WELL NUMBER CARIBBEAN SEA Figure 25.--Rfo Guanajibo basin. 388 RIO GDANAJIBO BASIN 50131990 RIO GUANAJIBO AT HWY 119 AT SAN GERMAN, PR LOCATION.—Lat 18005'06", 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, 0.2 mi (0.3 km) northeast of junction of Highways 119 and 102, 0.7 mi (1.1 km) east from public Plaza of San German. DRAINAGE AREA.--34.6 mi* (89.6 km 1 ). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--April 1991 to current year. GAGE.—Water-stage recorder. Elevation of gage is 148 ft (45 m), from topographic map. REMARKS.--Records poor. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 58 129 2 55 139 3 50 159 4 44 99 5 92 83 6 96 78 7 272 73 8 236 68 9 142 68 10 431 61 11 460 143 12 241 93 13 165 180 14 212 156 15 193 252 16 206 227 17 356 194 18 231 178 19 207 130 20 152 187 21 125 147 22 159 125 23 444 112 24 439 89 25 284 78 26 216 72 27 181 104 28 154 85 29 174 78 30 136 78 31 137 TOTAL 6348 3665 MEAN 205 122 MAX 460 252 MIN 44 61 MED 181 108 AC-FT 12590 7270 CFSM 5.92 3.53 IN. 6.83 3.94 STATISTICS OF MONTHLY MEAN MEAN 113 69.0 MAX 205 122 (WY) 1993 1993 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 96 77 65 60 59 58 54 52 50 47 41 38 80 111 75 54 46 40 39 36 34 33 32 31 31 73 52 42 40 36 35 1617 52.2 111 31 47 3210 1.51 1.74 DATA 30.2 52.2 1993 8.21 1992 FOR 32 31 31 30 28 28 33 31 27 25 25 25 25 24 23 22 21 20 19 19 19 25 24 20 18 17 16 18 145 64 55 940 30.3 145 16 25 1860 .88 1.01 53 47 38 32 28 23 23 21 21 17 13 12 15 16 24 61 52 35 30 25 21 19 17 18 24 18 16 14 -__ ___ —— 733 26.2 61 12 22 1450 .76 .79 FOR WATER YEARS 1991 33.8 37.3 1992 30.3 1993 15.1 26.2 1993 4.32 1992 17 16 14 11 10 10 10 11 10 8.3 11 12 13 13 15 15 13 11 10 9.8 9.2 8.6 9.8 9.9 9.7 8.9 12 19 12 8.9 8.3 356.4 11.5 19 8.3 11 707 .33 .38 - 1993 7.51 11.5 1993 3.52 1992 1992 CALENDAR YEAR 17868.5 48.8 817 1.5 1.8 35440 1.41 19.21 142 13 2.8 Jan 6 May 9 May 6 7.7 8.1 8.2 8.9 7.8 7.0 7.0 8.0 8.3 e8.6 el5 e45 e40 e35 e54 e70 e25 e!7 e!8 el4 e!3 elS ell e22 e23 e!4 el2 e25 e27 e23—— 597.6 19.9 70 7.0 14 1190 .58 .64 e70 e!40 el20 e98 e96 ellO 645 e35 e68 e56 e31 625 e23 e22 621 e20 e!9 e!8 617 e22 e20 e!9 e50 e70 e50 e60 6120 6130 e80 e200 e300 2155 69.5 300 17 50 4270 2.01 2.32 e80 e56 e45 e35 e32 e29 e28 e40 e96 e90 e45 e60 e54 e34 e31 e35 e24 e30 e72 e56 e41 e35 e33 e31 e31 e29 e28 eS5 e66 e69 1390 46.3 96 24 37 2760 1.34 1.49 643 e36 633 e30 e30 e33 648 e41 e28 e23 e21 621 e21 625 e20 618 e!8 619 el7 616 el6 e!5 e!6 615 elS 617 e!8 e!6 615 e!4 el4 712 23.0 48 14 19 1410 .66 .77 614 e!3 e!3 618 e21 e25 el9 e40 630 e22 617 el6 el4 e!7 621 e30 e20 e!8 616 elS e!4 635 e80 e25 e20 el7 621 e24 627 e28 618 708 22.8 80 13 20 1400 .66 .76 elS 615 e!9 e30 e27 623 el6 elS e45 e90 e60 e35 e34 e25 e22 619 e20 e25 e58 e40 631 e29 e!27 e55 e35 e46 e!73 elOl e64 eS7 1351 45.0 173 15 32 2680 1.30 1.45 . BY WATER YEAR (WY) 15.8 19.9 1993 11.7 1992 FOR 1993 20573. 56. 460 7. 7. 3120 10. 40810 1. 22. 141 30 13 49.3 69.5 1993 32.8 1991 WATER YEAR 0 4 Oct 11 0 Apr 6 8 Apr 1 Oct 10 41 Oct 10 63 12 21.0 46.3 1993 5.01 1991 17.2 23.0 1993 14.0 1992 WATER 38 56 20 817 1 1 6610 13 27920 1 15 78 16 4 22.2 22.8 1993 21.7 1991 YEARS 1991 - .5 .4 .8 Jan 6 . 5 May 9 . 8 May 6 Jan 6 .23 Jan 6 .11 .13 .3 37.2 53.7 1992 12.9 1991 1993 1993 1992 1992 1992 1992 1992 1992 e Estimated OOQ RIO GUANAJIBO BASIN «WW 50133600 RIO ODANAJIBO NEAR SAN GERMAN, PR WATBR-QOALITY RECORDS LOCATION.—Lat 18°07'18", long 67°03'56", at bridge on Highway 347, 2.2 ml (3.5 km) northwest of San German. DRAINAGE AREA.--45.5 mi> (117.8 km*). PERIOD OF RECORD.—Hater years 1979 to current year. HATER QUALITY DATA, HATER YEARS OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 22... DEC 29... FEB 1993 19... APR 21... JUN 03... SEP 08... TIME 1245 1225 1000 1435 1415 1040 DIS- CHARGE, INST. CUBIC FEET PER SECOND 89 64 42 100 56 49 SPE- CIFIC CON- DUCT- ANCE (US/CM) 480 520 459 552 522 534 PH HATER WHOLE FIELD (STAND- ARD UNITS) 7.2 8.0 7.9 7.2 7.8 7.3 TEMPER- ATURE HATER (DEG C) 26.0 22.9 24.2 29.0 31.7 27.6 TUR- BID- ITY (NTU) 24 12 18 17 2.1 0.60 OXYGEN, DIS- SOLVED (MG/L) 3.0 7.0 9.1 3.7 7.8 6.5 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 36 80 110 48 100 81 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) ^ 10 < 10 14 17 <10 <10 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 350 K1400 560 380 560 2500 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 210 240 210 430 480 260 DATE OCT 1992 22... DEC 29... FBB 1993 19... APR 21... JUN 03... SEP 08... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL HH HAT DIS- (MG/L TOT FLD SOLVED AS MG/L AS (MG/L CAC03) CACO3 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS NA) 220 12 25 39 10 220 0 25 38 19 230 6 26 41 23 SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY CHLO- SIUM, HAT HH 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) 0.3 1.5 0.6 3.0 0.7 2.7 CACO3 AS S) AS SO4) AS CL) <0.5 230 240 180 210 <0.5 160 170 18 28 27 14 27 24 SOLIDS, DATE OCT 1992 22... DEC 29... FBB 1993 19... APR 21... JUN 03... SEP 08... FLUO- RIDB, DIS- SOLVED (MG/L AS F) <0.10 -- -- 0.10 -- 0.10 SILICA, DIS- SOLVED (MG/L AS SI02) 37 -- -- 32 -- 34 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 282 -- -- 299 -- 311 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 FENDED (MG/L (MG/L (MG/L (MG/L (MG/L DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) <1 12 16 <1 21 5 0.870 0.500 0.650 0.510 0.400 0.630 0.030 0.100 0.050 0.090 0.100 0.070 0.900 0.600 0.700 0.600 0.500 0.700 0.070 2.40 0.140 0.390 1.20 0.570 0.33 0.80 0.36 0.51 0.40 0.43 non-ideal count 390 DATE OCT 1992 22... DEC 29.. . FEE 1993 19... APR 21.. . •TON 03... SEP 08... DATE OCT 1992 22... DEC 29... FBB 1993 19.. . APR 21... •TON 03.. . SEP 08... RIO GUANAJIBO BASIN 50133600 RIO GUANAJIBO NEAR SAN GERMAN, PR--Continued WATER QUALITY DATA, WATER YEARS OCTOBER 1992 TO SEPTEMBER 1993 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.40 3.2 0.50 0.90 1.6 1.0 IRON, TOTAL RECOV- ERABLE (UG/L AS FE) NITRO- GEN, TOTAL (MG/L AS N) 1.3 3.8 1.5 2.1 1.7 0.50 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N03) 5.8 17 6.6 9.3 7.5 12 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.200 1.80 0.400 0.560 0.250 0.350 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 -- -- 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 -- -- 10 -- -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CD) 10 — — 10 — -- MBTHY- LBNE BLUE ACTIVE SUB- STANCE (MG/L) 730 1100 140 230 <0.10 <0.10 20 10 <0.010 <0.010 0.05 0.02 RIO GUANAJIBO BASIN 391 50136400 RIO ROSARIO NEAR HORMIGUEROS, PR LOCATION.—Lat 18«09'36", long 67«05'08", Hydrologic Unit 21010003 at bridge on Highway 348, 0.5 mi (0.8 km) southwest of Rosario plaza. DRAINAGE AREA.--18.3 mi> (47.4 km9 ). WATER-DISCHARGE RECORDS PERIOD OP RECORD.—October 1985 to current year. GAGE.—Water-stage recorder. Elevation of gage is 50.0 ft (15.2 m) , from topographic map. REMARKS.—Records fair. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC PBBT PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUQ SEP 1 373 131 2 196 98 3 132 80 4 102 76 5 90 67 6 117 64 7 116 59 8 147 55 9 116 51 10 385 49 11 204 47 12 140 63 13 104 80 14 78 229 15 67 209 16 139 133 17 325 89 18 199 140 19 135 119 20 104 120 21 79 95 22 93 107 23 183 95 24 208 68 25 157 56 26 113 49 27 83 46 28 67 52 29 113 76 30 157 53 31 158 TOTAL 4680 2656 MEAN 151 88.5 MAX 385 229 MIN 67 46 AC-FT 9280 5270 CPSM 8.25 4.84 IN. 9.51 5.40 STATISTICS OP MONTHLY MEAN MEAN 111 76.0 MAX 206 117 (WY) 1986 1990 MIN 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 RUNOPP (AC- FT) ANNUAL RUNOPP (CPSM) ANNUAL RUNOPP (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 42 37 36 34 51 38 30 29 26 25 24 23 31 69 42 25 22 20 19 18 17 17 16 20 16 17 16 16 16 19 16 827 26.7 69 16 1640 1.46 1.68 DATA 30.1 43.2 1990 9.92 1992 POR 16 16 16 16 18 19 18 17 17 17 18 18 18 18 19 19 19 21 20 20 20 20 19 18 18 18 17 18 162 40 46 756 24.4 162 16 1500 1.33 1.54 96 44 33 28 26 24 23 22 22 22 22 22 23 22 20 104 73 31 25 22 20 19 18 18 18 17 16 17 ___ —— 847 30.2 104 16 1680 1.65 1.72 POR WATER YEARS 1986 21.0 31.8 1990 15.9 1991 17.1 30.2 1993 8.55 1992 18 18 16 16 16 16 16 18 23 16 16 15 15 15 14 14 14 14 13 13 13 13 14 16 15 18 30 20 15 15 17 502 16.2 30 13 996 .88 1.02 - 1993 21.5 77.0 1989 10.1 1992 1992 CALENDAR YEAR 17618.8 48.1 502 3.9 4.2 34950 2.63 35.82 134 17 6.9 Sep 30 May 9 May 6 15 14 15 13 14 13 13 13 16 12 79 167 112 54 28 19 16 25 18 12 17 15 11 52 22 13 12 32 21 19 —— 882 29.4 167 11 1750 1.61 1.79 201 271 225 140 257 150 75 52 117 83 58 51 49 47 42 43 45 44 43 50 46 43 116 65 52 175 270 166 113 525 182 3796 122 525 42 7530 6.69 7.72 113 83 69 60 55 54 53 87 149 133 82 123 97 72 65 69 59 58 82 84 66 62 58 52 58 71 74 176 328 142 —— 2734 91.1 328 52 5420 4.98 5.56 70 54 48 44 63 86 257 115 63 50 46 45 43 46 42 39 38 37 37 37 36 44 45 42 43 49 47 40 40 40 40 1726 55.7 257 36 3420 3.04 3.51 41 40 41 45 51 39 40 42 49 42 39 38 37 37 36 82 46 37 34 32 34 140 64 31 39 39 54 110 125 117 68 1669 53.8 140 31 3310 2.94 3.39 57 78 131 239 145 101 110 132 508 195 158 179 163 133 109 94 128 168 176 154 132 118 112 104 95 127 223 305 188 148 —— 4710 157 508 57 9340 8.58 9.57 , BY WATER YEAR (WY) 24.2 57.7 1989 11.9 1991 POR 1993 25785 70. 525 11 13 5000 12. 10 51140 3. 52. 157 45 16 50.7 122 1993 15.8 1990 WATER YEAR 6 May 30 Apr 23 Mar 16 May 30 06 May 30 Apr 21 86 42 50.2 91.1 1993 12.0 1992 45.3 75.2 1989 23.2 1990 WATER 50. 70. 30. 1550 3. 4. 7480 13. 3. 36870 2. 37. 122 27 11 60.2 102 1989 25.1 1991 YEARS 1986 - 9 6 8 Oct 7 9 May 9 2 May 6 Aug 24 64 Aug 24 7 May 9 78 79 102 157 1993 32.7 1986 1993 1993 1992 1985 1992 1992 1988 1988 1992 392 RIO GDANAJIBO BASIN 50136400 RIO ROSARIO NEAR HORMIGDBROS, PR—Continued WATER-QUALITY RECORDS PERIOD OF RECORD.—Water years 1979 to current year. PERIOD OF DAILY RECORD.— SUSPENDED-SEDIMENT DISCHARGES October 1985 to September 1993. INSTRUMENTATION.--US D-49 SEDIMENT 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 size analyses. Sediment samples are collected periodically by survey staff. Automatic sediment sampler set to collect samples above 200 cfs. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATIONSt Maximum daily mean, 8,150 mg/L October 7, 1985; Minimum daily mean, 1 mg/L January 28, 1990. SEDIMENT LOADS* Maximum daily, 74,700 tons (67,800 tonnes) October 7, 1985; Minimum daily, 0.05 ton (0.04 Tonne) several days. EXTREMES FOR CURRENT YEAR.-- SEDIMENT CONCENTRATIONSi Maximum daily mean, 1,910 mg/L June 29, 1993; Minimum daily mean, 2.0 mg/L several days. SEDIMENT LOADS* Maximum daily, 7,830 tons (7,100 tonnes) May 30, 1993; Minimum daily 0.08 ton (0.07 tonne) several days. WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 23... DEC 29... FBB 1993 18... APR 21... JUN 04... SEP 08... TIME 1425 1115 1325 1250 1345 1300 DIS- CHARGE, INST. CUBIC FEET PER SECOND 66 15 2.89 11 56 74 SPE- CIFIC CON- DUCT- ANCE (US/CM) 230 276 258 300 282 232 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.2 8.2 8.0 7.9 8.0 7.2 TEMPER- ATURE WATER (DBG C) 27.0 21.8 23.4 26.5 28.2 24.7 TUR- BID- ITY (NTU) 17 3.1 4.0 3.5 2.8 5.2 OXYGEN, DIS- SOLVED (MG/L) 8.0 9.0 10.6 5.3 7.6 7.8 OXYGEN, OXYGEN DIS- DEMAND, SOLVED CHSM- (PBR- ICAL CENT (HIGH SATUR- LEVEL) ATION) (MG/L) 100 40 102 <10 122 <10 65 <10 97 <10 92 <10 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 3100 730 320 420 3000 2700 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 610 550 250 310 5900 680 DATE OCT 1992 23... DEC 29... FEB 1993 18... APR 21... JUN 04. .. SEP 08. .. HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MG/L TOT FLO SOLVED AS MG/L AS (MG/L CAC03) CAC03 MAGNE- SIUM, DIS- SODIUM, DIS- SOLVED SOLVED (MG/L AS CA) AS MG) AS NA) 110 7 19 15 120 5 24 14 120 4 20 16 SODIUM AD- SORP- TION (MG/L RATIO ALKA- POTAS- LINITY SIUM, WAT WH DIS- SULFATB TOT PET SULFIDB DIS- SOLVED FIELD AS K) 5.6 0.2 1.2 7.8 0.3 1.7 7.0 0.3 1.7 CACO3 98 150 150 130 150 85 TOTAL (MG/L MG/L AS (MG/L <0.5 <0.5 SOLVED (MG/L 6.9 7.0 6.5 CHLO- RIDE, DIS- SOLVED (MG/L AS S) AS SO4) AS CL) 5.9 8.9 5.8 RIO GUANAJIBO BASIN 50136400 RIO ROSARIO NEAR HORMIGDBROS, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 393 SOLIDS, RESIDUE DATE OCT 1992 23... DEC 29... FBB 1993 18... APR 21.. . OUN 04... SEP 08... DATE OCT 1992 23... DEC 29.. . FBB 1993 18... APR 21... OUN 04... SEP 08... DATE OCT 1992 23... DEC 29... FBB 1993 18... APR 21... JUN 04.. . SEP 08... FLUO- RIDB, DIS- SOLVED (MG/L AS F) <0.10 -- -- <0.10 -- 0.10 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.20 0.30 0.30 0.30 0.30 0.20 IRON, TOTAL RECOV- ERABLE (UG/L AS FE) 120 -- -- 180 -- -- SILICA, DIS- SOLVED (MG/L AS SI 02) 29 -- -- 29 — 27 NITRO- GEN, TOTAL (MG/L AS N) 1.0 0.70 1.2 0.60 0.70 0.90 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) 4 — -- <1 -- -- SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 141 -- -- 170 -- 149 NITRO- GEN, TOTAL (MG/L AS N03) 4.4 3.4 4.1 2.7 3.1 2.9 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) 30 -- -- 20 -- -- SOLIDS, DIS- SOLVED (TONS PER DAY) 25.1 -- -- 4.97 -- 29.8 PHOS- PHORUS TOTAL (MG/L AS P) 0.050 0.090 0.050 0.060 0.020 0.040 MERCURY TOTAL RECOV- ERABLE (UG/L AS HG) <0.10 -- — <0.10 __ -- TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) <1 10 8 2 19 13 ARSENIC TOTAL (UG/L AS AS) <1 -- -- <1 -- -- SELE- NIUM, TOTAL (UG/L AS SB) <1 -- -- <1 __ -- NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.730 0.680 0.790 0.590 0.390 0.380 BARIUM, TOTAL RECOV- ERABLE (UG/L AS BA) <100 -- -- <100 -- — — SILVER, TOTAL RECOV- ERABLE (UG/L AS AG) <1 -- -- <1 __ -- NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.010 0.020 0.010 0.010 0.010 0.020 BORON, TOTAL RECOV- ERABLE (UG/L AS B) 40 -- -- 30 -- — — ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) <10 -- -- <10 __ -- NITRO- GEN, NO2+NO3 TOTAL (MG/L AS N) 0.730 0.700 0.800 0.600 0.400 0.400 CADMIUM TOTAL RECOV- ERABLE (UG/L AS CD) <1 -- -- <1 -- — — CYANIDE TOTAL (MG/L AS CN) <0.010 -- -- •cO.010 __ -- NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.010 0.010 0.030 0.040 0.010 0.010 CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L AS CR) 1 -- -- 2 -- — — PHENOLS TOTAL (UG/L) 2 -- -- 3 -_ -- NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.19 0.29 0.27 0.26 0.29 0.19 COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) <10 -- — <10 -- — — MBTHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 0.01 -- -- 0.02 -- — 394 RIO GUANAJIBO BASIN 50136400 RIO ROSARIO NEAR HORMIGUBROS, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) NOVEMBER 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) 373 196 132 102 90 117 116 147 116 385 204 140 104 78 67 140 326 199 135 104 79 93 183 208 157 113 83 67 113 157 158 MEAN CONCEN- TRATION (MG/L) OCTOBER 1280 347 31 21 45 196 199 240 133 1670 229 183 81 28 34 1530 1320 411 130 31 26 94 491 502 217 25 19 16 201 401 285 SEDIMENT DISCHARGE (TONS/DAY) 2160 208 11 5.7 14 153 134 117 47 6060 161 74 25 6.1 6.4 1960 2560 250 54 8.6 5.5 43 489 348 118 7.6 4.2 3.0 139 469 156 131 98 80 76 67 64 59 55 51 49 47 63 80 229 209 133 89 140 119 120 95 107 95 68 56 49 46 52 76 53 92 23 17 101 21 11 10 10 11 11 10 68 138 860 619 188 79 447 180 138 48 105 44 14 12 11 16 31 86 36 41 6.1 3.7 26 3.9 1.9 1.6 1.5 1.4 1.4 1.2 22 65 1920 603 80 19 386 76 68 13 47 13 2.6 1.8 1.4 1.9 4.7 34 5.9 MEAN DISCHARGE (CPS) 42 37 36 34 51 38 30 29 26 25 24 23 31 69 42 25 22 20 19 18 17 17 16 20 16 17 16 16 16 19 16 MEAN CONCEN- TRATION (MG/L) DECEMBER 14 12 21 22 48 29 15 9 14 37 22 8 26 99 23 14 12 16 13 8 11 10 15 67 58 83 43 11 9 11 12 SEDIMENT DISCHARGE (TONS/DAY) 1.6 1.2 2.0 2.1 17 3.2 1.3 .68 .99 2.5 1.4 .49 11 26 3.1 1.0 .68 .82 .63 .39 .51 .43 .60 4.3 2.7 4.3 1.9 .46 .42 .56 .50 TOTAL 4682 15797.1 2656 3454.0 827 94.76 RIO GUANAJIBO BASIN 50136400 RIO ROSARIO NEAR HORMIGUBROS, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 MEAN MEAN CONCBN- SEDIMENT DISCHARGE TRATION DISCHARGE (CFS) (MG/L) (TONS/DAY) FEBRUARY 395 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 16 16 16 16 18 19 18 17 17 17 18 18 18 18 19 19 19 21 20 20 20 20 19 18 18 18 17 18 162 40 46 13 12 10 11 12 11 10 8 6 5 7 16 28 28 18 10 8 11 10 7 7 9 10 10 7 5 6 10 477 23 72 .52 .46 .42 .46 .55 .55 .45 .37 .30 .26 .34 .78 1.3 1.4 .92 .51 .46 .62 .56 .39 .40 .49 .50 .46 .37 .27 .30 .47 532 3.0 60 96 44 33 28 26 24 23 22 22 22 22 22 23 22 20 104 73 31 25 22 20 19 18 18 18 17 16 17 205 16 12 10 10 10 8 8 7 7 7 7 6 4 4 303 73 16 9 6 5 5 5 5 4 4 4 4 148 1.9 1.1 .75 .68 .60 .53 .49 .46 .43 .42 .43 .38 .27 .24 282 23 1.4 .62 .36 .27 .25 .24 .25 .23 .19 .18 .18 MEAN DISCHARGE (CFS) 18 18 16 16 16 16 16 18 23 16 16 15 15 15 14 14 14 14 13 13 13 13 14 16 15 18 30 20 15 15 17 MEAN CONCEN- TRATION (MG/L) MARCH 3 2 2 2 2 2 3 7 9 4 4 5 5 5 6 5 5 5 4 3 4 7 7 5 5 7 17 7 7 7 6 SEDIMENT DISCHARGE (TONS/ DAY) .17 .12 .08 .08 .08 .08 .13 .39 .69 .18 .19 .20 .20 .21 .22 .20 .18 .18 .16 .11 .15 .29 .28 .20 .20 .57 2.3 .37 .29 .28 .24 TOTAL 756 609.88 847 465.85 502 9.02 396 RIO GUANAJIBO BASIN 50136400 RIO ROSARIO NEAR HORMIGUBROS, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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 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 14 15 13 14 13 13 13 16 12 79 167 112 54 28 19 16 25 18 12 17 15 11 52 22 13 12 32 21 19 APRIL 5 5 5 5 5 6 6 5 4 4 184 609 241 57 41 28 13 19 23 16 11 10 11 87 102 68 60 89 41 13 MAY .19 .18 .18 .18 .18 .21 .22 .17 .18 .13 164 1120 212 9.5 3.3 1.5 .57 3.1 1.2 .53 .95 .41 .32 40 6.9 2.5 2.0 8.0 2.6 .65 ___ 201 271 225 140 257 150 75 52 117 83 58 51 49 47 42 43 45 44 43 50 46 43 116 65 52 175 270 166 113 525 182 371 617 654 211 1310 240 67 33 290 61 19 14 7 5 5 5 4 4 5 5 6 9 250 50 32 639 634 277 123 1210 264 787 1170 838 96 2840 115 16 4.8 252 15 3.1 1.9 .99 .63 .57 .57 .54 .53 .57 .69 .80 1.0 198 9.8 4.6 1360 1210 136 40 7830 149 JUNE 113 83 69 60 55 54 53 87 149 133 82 123 97 72 65 69 59 58 82 84 66 62 58 52 58 71 74 176 328 142 109 31 11 8 5 5 5 127 450 171 76 302 100 36 10 5 4 10 54 62 25 10 4 4 5 6 6 543 1910 218 37 7.7 2.0 1.3 .82 .72 .72 68 402 68 19 315 29 7.1 1.8 .96 .71 1.7 14 16 4.8 1.7 .67 .62 .89 1.2 1.1 729 3710 103 TOTAL 882 1581.85 3796 17083.09 2734 5546.51 RIO GUANAJIBO BASIN 50136400 RIO ROSARIO NEAR HORMIGUEROS, PR—Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 397 MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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 70 54 48 44 63 86 257 115 63 50 46 45 43 46 42 39 38 37 37 37 36 44 45 42 43 49 47 40 40 40 40 1726 25787 JULY 48 15 10 10 50 122 1000 153 37 15 10 10 8 8 7 6 5 4 4 4 4 6 9 9 7 6 5 4 3 3 3 ... AUGUST 10 2. 1. 1. 13 64 3040 62 6. 2. 1. 1. . 1. • . . . . • . . 1. 1. . . . . . • 3217. 65304. 3 3 2 8 1 2 1 99 0 91 67 55 45 41 40 45 78 1 0 91 86 64 43 37 32 33 57 78 41 40 41 45 51 39 40 42 49 42 39 38 37 37 36 82 46 37 34 32 34 140 64 31 39 39 54 110 125 117 68 1669 3 2 2 3 19 12 8 22 42 14 4 4 4 4 10 57 8 4 6 7 7 489 57 13 33 35 44 610 194 236 110 ... 4 1 2 7 1 16 1 795 17 1 6 4 7 731 98 93 21 1815 .32 .26 .22 .42 .4 .4 .90 .3 .3 .8 .43 .42 .39 .39 .95 .1 .45 .54 .62 .64 .1 .2 .5 .1 .15 MEAN DISCHARGE (CPS) MEAN CONCEN- SEDIMENT TRATION DISCHARGE (MG/L) (TONS/DAY) SEPTEMBER 57 78 131 239 145 101 110 132 508 195 158 179 163 133 109 94 128 168 176 154 132 118 112 104 95 127 223 305 188 148 --- 4710 65 116 568 963 218 111 128 238 1490 355 224 436 151 68 52 16 395 326 339 373 126 67 126 38 10 206 633 873 48 16 --- --- 10 45 1040 2350 98 38 46 144 7640 212 120 398 75 30 17 4.1 355 270 191 284 47 25 45 11 2.6 163 607 1330 26 6.3 --- 15630.0 398 RIO GOANAJIBO BASIN 50136400 RIO ROSARIO NEAR HORMIGUEROS, PR--Continued WATER QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT DATE OCT 1992 10. .. NOV 15. .. APR 1993 12... MAY 30... JUN 28. . . AUG 28. .. SEP 09... DATE OCT 1992 10... NOV 15. .. APR 1993 12. .. MAY 30. .. JUN 06... AUG 28. .. SEP 03. .. TIME 1608 1829 1304 1625 1635 1832 1800 SED. SUSP. FALL DIAM. PERCENT FINER THAN .016 MM 28 71 98 50 28 47 55 DIS- CHARGE, INST. CUBIC FEET PER SECOND 2960 432 967 4290 647 570 1050 SED. SUSP. FALL DIAM. PERCENT FINER THAN .031 MM 33 80 98.9 59 34 59 67 SEDI- MENT, SUS- PENDED (MG/L) 23600 2460 4110 13800 6460 10300 955 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 41 91 — 70 45 74 77 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 188000 2870 10700 160000 11300 15800 27000 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .125 MM 58 96 -- 83 61 82 93 SED. SUSP. FALL DIAM. PERCENT FINER THAN .002 MM 15 42 58 32 17 29 31 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN .250 MM 84 99 99 94 77 87 98 SED. SUSP. FALL DIAM. PERCENT FINER THAN .004 MM 19 55 -- 36 20 32 37 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .500 MM 96 99.7 99.7 99 89 94 98.9 SBD. SUSP. FALL DIAM. PERCENT FINER THAN .008 MM 23 59 88 41 23 38 48 SED. SUSP. SIEVE DIAM. PERCENT FINER THAN 1.00 MM 98 100 100 100 97 99 99 RIO GDANAJIBO BASIN 399 50136400 RIO ROSARIO NEAR HORMIGUBROS , PR--Continued HATER QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT DATE OCT 1992 01.. . NOV 10... 10... 10... 10... 10... 16... 17... 17... 18.. . MAR 1993 27.. . APR 12... MAY 01.. . 02... 02... 02.. . 05... 05... 09.. . 23... 27... 30.. . 30... JUN 09... JUL 07... AUG 22... SEP 04.. . 12... 27... 28.. . TIME 1750 1538 1545 1735 1905 2105 1821 1654 1749 1958 1802 1305 1655 1525 1630 1745 1615 2000 1615 0640 1635 1540 2010 1830 1820 1955 1438 1815 1857 1740 STREAM- PLOW, INSTAN- TANEOUS (CFS) 471 1390 1750 1170 655 442 350 945 855 283 87 967 1270 1210 671 515 646 470 470 190 850 1990 573 364 609 688 453 599 470 380 SEDI- MENT, SUS- PENDED (MG/L) 11600 10600 13800 5350 3100 1700 16600 11400 2150 1790 1220 7290 6250 4450 2370 2180 10200 1970 1590 2100 2430 7400 1630 1560 3300 4870 4880 1930 2210 1550 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 14750 39780 65200 16900 5480 2030 15690 29090 4960 1370 4220 19030 22360 14540 4290 3030 17790 2500 2020 1080 5580 39760 2570 1530 5430 9050 6230 3120 2800 1590 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 41 57 65 81 88 91 25 38 89 96 97 69 68 69 89 87 42 85 84 98 86 70 88 92 89 51 83 62 90 86 400 RIO GUANAJIBO BASIN 50138000 RIO GOANAJIBO NEAR HORMIQUBROS, PR LOCATION.--Lat 18°08'36", long 67 0 08'57", Hydrologic Unit 21010003, at bridge on Highway 100, 1.4 mi (2.3 km) west of Hormigueros, and 2.0 mi (3.2 km) downstream from Rio Rosario. DRAINAGE AREA.--120 mi* (311 km*). WATER-DISCHARGE RECORDS PERIOD OF RECORD.—Annual low-flow measurements 1959, monthly measurements April 1959 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 (0.5 km) upstream at datum 7.36 ft (2.243 m) higher. REMARKS.--Records 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. DISCHARGE, CUBIC FEET PER SECOND, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 956 489 2 450 392 3 297 396 4 248 533 5 256 412 6 496 290 7 500 251 8 1140 226 9 855 217 10 1080 210 11 3360 226 12 1850 337 13 975 324 14 611 509 15 569 653 16 519 695 17 994 515 18 1290 564 19 642 576 20 501 728 21 423 625 22 412 499 23 535 436 24 1210 341 25 879 286 26 568 243 27 450 285 28 380 324 29 460 321 30 455 420 31 529 TOTAL 23890 12323 MEAN 771 411 MAX 3360 728 MIN 248 210 AC-FT 47390 24440 CFSM 6.42 3.42 IN. 7.41 3.82 STATISTICS OF MONTHLY MEAN MEAN 503 440 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 351 328 251 214 184 185 160 147 139 133 121 112 132 318 211 135 120 111 106 100 98 95 93 94 101 194 169 107 107 108 100 4824 156 351 93 9570 1.30 1.50 DATA 132 422 1976 15.4 1992 92 86 85 82 81 85 95 118 93 82 78 76 73 72 74 69 67 65 64 63 63 63 67 60 58 56 55 51 681 369 279 3402 110 681 51 6750 .91 1.05 340 251 187 134 109 89 82 75 70 68 65 62 60 56 55 117 226 92 73 63 59 54 51 49 56 51 49 47 ___ ___ 2690 96.1 340 47 5340 .80 .83 FOR WATER YEARS 1973 59.3 110 1993 13.8 1973 47.2 96.1 1993 13.9 1977 48 50 43 40 39 39 38 39 46 37 34 33 33 30 33 48 50 35 31 30 27 27 26 30 31 29 122 103 49 55 46 1321 42.6 122 26 2620 .36 .41 - 1993 44.9 244 1989 10.6 1977 FOR 1992 CALENDAR YEAR 74264.4 203 3360 6.2 7.6 147300 1.69 23.02 534 69 15 Oct 11 May 11 May 7 36 32 30 31 31 28 28 26 32 28 59 160 136 122 184 254 85 57 62 45 45 51 38 75 78 47 40 82 90 76 --- 2088 69.6 254 26 4140 .58 .65 209 462 406 328 325 377 164 121 228 192 121 105 91 83 78 73 68 64 61 75 68 62 179 259 166 192 402 451 266 657 1060 7393 238 1060 61 14660 1.99 2.29 286 200 153 123 107 97 94 139 325 306 153 199 179 113 104 124 94 92 244 212 126 100 90 82 76 72 69 164 446 441 5010 167 446 69 9940 1.39 1.55 143 110 97 87 84 109 255 306 129 103 92 88 119 114 86 75 69 67 65 60 58 57 62 58 58 65 67 56 54 53 53 2899 93.5 306 53 5750 .78 .90 53 51 51 68 79 94 69 152 122 80 60 58 52 65 78 311 200 133 115 104 96 450 873 236 190 168 211 246 274 285 176 5200 168 873 51 10310 1.40 1.61 152 152 189 309 244 210 203 313 843 1020 375 349 348 235 205 184 205 367 589 330 254 211 459 532 245 454 764 1230 724 375 12070 402 1230 152 23940 3.35 3.74 , BY WATER YEAR (WY) 71.0 316 1989 16.1 1977 FOR 1993 83110 228 3360 26 29 5310 21 164800 1 25 517 115 46 185 636 1980 12.7 1977 WATER YEAR Oct 11 Mar 23 Mar 20 Oct 11 .84 Oct 11 .90 .76 114 504 1979 9.23 1977 106 240 1984 26.4 1976 WATER 206 402 104 35000 5 5 128000 28 4 148900 1 23 456 78 21 230 757 1988 42.3 1976 YEARS 1973 Sep .0 Jun .5 Jun Sep .50 Sep .6 Jun .71 .27 502 2075 1975 95.4 1991 - 1993 1979 1992 16 1975 18 1977 17 1977 16 1975 16 1975 22 1977 RIO GUANAJIBO BASIN 50138000 RIO GUANAJIBO NEAR HORMIGUEROS, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1958 to current year. WATER-QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 407 DATE OCT 1992 23... DEC 11... FEB 1993 18. .. APR 20. .. JUN 03. .. AUG 19... TIME 1230 1045 1120 1340 1320 1145 DIS- CHARGE, INST. CUBIC FEET PER SECOND 485 128 102 48 170 119 SPE- CIFIC CON- DUCT- ANCE (US /CM) 345 480 381 450 414 400 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7,0 8.0 7.9 7.5 7.6 7.3 TEMPER- ATURE WATER (DEG C) 27.0 23.8 23.5 28.0 29.0 28.5 TUR- BID- ITY (NTU) 44 10 14 1.0 13 2.0 OXYGEN, DIS- SOLVED (MG/L) 4.9 6.8 8.6 4.1 5.3 3.4 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 61 74 99 52 68 42 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) <10 <10 <10 13 <10 38 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K41000 500 2400 530 4400 1400 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 5100 210 570 480 660 530 DATE OCT 1992 23. .. DEC 11... FEB 1993 18. .. APR 20... JUN 03. .. AUG 19... 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 CACO3) CACO3 AS CA) AS MG) AS NA) 160 22 24 25 8.4 210 30 30 32 16 220 8 40 29 140 ALKA- POTAS- LINITY SIUH, WAT WH DIS- TOT FET SULFIDE SOLVED FIELD TOTAL (MG/L MG/L AS (MG/L AS K) 0.3 2.2 0.5 2.4 9.0 CACO3 160 220 170 200 190 130 CHLO- SULFATE RIDE, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS S) AS SO4) AS CL) <0.5 13 <0.5 18 76 11 18 210 SOLIDS, RESIDUE FLUO- SILICA, SUM OF SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- DATE OCT 1992 23.. . DEC 11... FEB 1993 18.. . APR 20... JUN 03... AUG 19... RIDE, DIS- SOLVED (MG/L AS F) 0.10 -- -- 0.10 -- 0.20 DIS- SOLVED (MG/L AS SIO2) 29 -- -- 19 -- 25 CONSTI- TUENTS, DIS- SOLVED (MG/L) 209 -- -- 255 -- 268 DIS- SOLVED (TONS PER DAY) 273 -- -- 32.8 -- 73.2 AT 105 DBG. C, SUS- PENDED (MG/L) 4 <1 27 21 39 8 GEN, NITRATE TOTAL (MG/L AS N) 0.530 0.630 0.760 0.770 0.860 0.750 GEN, NITRITE TOTAL (MG/L AS N) 0.020 0.070 0.040 0.030 0.040 0.050 GEN, NO2+NO3 TOTAL (MG/L AS N) 0.550 0.700 0.800 0.800 0.900 0.800 GEN, AMMONIA TOTAL (MG/L AS N) 0.050 0.410 0.230 0.140 0.320 0.290 GEN, ORGANIC TOTAL (MG/L AS N) 0.55 0.09 0.37 0.36 0.58 0.51 402 DATE OCT 1992 23... DEC 11... FBB 1993 18... APR 20... JUN 03... AUG 19.. . RIO QUANAJIBO BASIN 50138000 RIO QUANAJIBO NEAR HORMIGUBROS, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 BARIUM, BORON, CADMIUM TOTAL TOTAL TOTAL RBCOV- RBCOV- RECOV- ERABLE BRABLB BRABLB (UG/L (UG/L (UG/L 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) 0.60 0.50 0.60 0.50 0.90 0.80 AS N) AS N03) AS P) AS AS) AS BA) AS B) 1.2 1.2 1.4 1.3 1.8 1.6 5.1 5.3 6.2 5.8 8.0 7.1 0.280 0.460 0.190 0.280 0.220 0.310 <1 <100 20 <1 <1 <100 30 <1 CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L COPPER, TOTAL RECOV- ERABLE (UG/L AS CD) AS CR) AS CO) DATE OCT 1992 23... DEC 11.. . FBB 1993 18... APR 20.. . JUN 03... AUG 19... 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 (DG/L AS AG) ZINC, TOTAL RECOV- ERABLE (UG/L AS ZN) CYANIDE TOTAL (MG/L AS CN) PHENOLS TOTAL (UG/L) MBTHY- LHNB BLUB ACTIVE SUB- STANCE (MG/L) 1100 570 <1 120 100 <0.10 <0.10 <1 <1 <1 <1 10 <0.010 20 <0.010 <1 0.04 0.03 PESTICIDE ANALYSES DATE JUN 1993 25... CHLOR- PCB, ALDRIN, DANE, TIME TOTAL TOTAL TOTAL (UG/L) (UG/L) (UG/L) 1100 <0.1 <0.010 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 SULFAN, TOTAL TOTAL (UG/L) (UG/L) <0.01 <0.010 <0.010 BNDRIN WATER HBPTA- UNFLTRD BTHION, CHLOR, DATE REC TOTAL TOTAL (UG/L) (UG/L) (UG/L) JUN 1993 25... HEPTA- CHLOR BPOXIDB LINDANB TOTAL TOTAL (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 DATE JUN 1993 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 TOTAL (UG/L) SILVBX, TOTAL (UG/L) <0.01 <0.10 <1 <0.01 0.06 <0.01 <0.01 <0.01 EXPLANATION A 144° SURFACE-WATER STATION AND NUMBER V 1388 QUALITY-OF-WATER STATION AND NUMBER • U15 LAKE-ELEVATION STATION 0123456 KiLOMETERS 01234 MILES Figure 26.--Rio Yagiiez and Rio Grande de Anasco basins. o 00 RIO YAGOEZ BASIN 50138800 RIO YAG0EZ NEAR MAYAGUEZ, 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 MayagXez plaza. DRAINAGE AREA.--6.7 mi 9 (17.3 km> ). PERIOD OF RECORD.—Water years 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 29... DEC 11... FEE 1993 18... APR 20... JUN 04... AUG 19... TIME 1420 1210 1450 1515 1000 0800 DIS- PH CHARGE, SPB- WATER INST. CIFIC WHOLE CUBIC CON- FIELD TEMPER- FEET DUCT- (STAND- ATURB PER ANCE ARD WATER SECOND (US/CM) UNITS) (DBG C) 9.0 7.4 11 5.7 5.0 8.5 276 316 286 295 279 306 7.4 8.1 7.9 7.6 8.0 7.4 29.0 23.9 23.8 27.5 25.8 24.0 OXYGEN, OXYGEN COLI- DIS- DEMAND, FORM, STREP- SOLVED CHEM- FECAL, TOCOCCI TOR- OXYGEN, (PER- ICAL 0.45 FECAL, BID- DIS- CENT (HIGH UM-MF (COLS. ITY SOLVED SATUR- LEVEL) (COLS./ PER (NTU) (MG/L) ATION) (MG/L) 100 ML) 100 ML) 0.80 1.1 1.2 0.60 2.2 0.70 5.1 9.5 10.5 5.0 7.7 4.2 66 112 124 63 94 49 12 2000 <10 220 <10 1300 <10 240 19 350 <10 K1300 680 580 810 310 440 2100 DATE OCT 1992 29... DEC 11... FEB 1993 18... APR 20... JUN 04... AUG 19... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH WAT DIS- (MG/L TOT FLD SOLVED AS MG/L AS (MG/L CACO3) CACO3 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS CA) AS MG) AS NA) 180 12 27 16 20 130 20 34 12 12 140 3 36 11 13 SODIUM AD- SORP- TION RATIO ALKA- POTAS- LINITY SIUM, WAT WH DIS- TOT PET SULFIDB SOLVED FIELD TOTAL (MG/L MG/L AS (MG/L AS K) 0.4 1.9 0.5 2.7 0.5 2.4 CACO3 130 130 120 140 120 100 CHLO- SULFATB RIDE, DIS- DIS- SOLVED SOLVED (MG/L <0.5 17 <0.5 8.3 7.4 (MG/L AS S) AS SO4) AS CL) 12 11 9.8 DATE OCT 1992 29... DEC 11... FBB 1993 18... APR 20... JUN 04... AUG 19... FLUO- RIDB, DIS- SOLVED (MG/L AS F) 0.20 -- -- 0.10 -- <0.10 SILICA, DIS- SOLVED (MG/L AS SIO2) 30 — — 29 — 32 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 224 -- -- 193 -- 194 SOLIDS, DIS- SOLVED (TONS PER DAY) 5.44 — — 2.97 — 4.45 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) <1 5 8 6 17 4 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 0.920 0.540 0.790 0.890 0.730 0.620 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.010 0.060 0.010 0.010 0.070 0.080 NITRO- GEN, NO2+N03 TOTAL (MG/L AS N) 0.930 0.600 0.800 0.900 0.800 0.700 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.020 0.650 0.020 0.010 0.160 0.390 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.48 0.15 0.18 0.19 0.44 0.41 non-ideal count DATE OCT 1992 29... DEC 11... FEB 1993 18... APR 20... JUN 04... AUG 19... DATE OCT 1992 29... DEC 11... FEB 1993 18... APR 20... JUN 04... AUG 19... RIO YAGUBZ BASIN 50138800 RIO YAGUEZ NEAR MAYAGUBZ, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 405 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.50 0.80 0.20 0.20 0.60 0.80 IRON, TOTAL RECOV- ERABLE (UG/L AS FE) NITRO- GEN, TOTAL (MG/L AS N) 1.0 1.1 1.3 1.2 1.4 1.2 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N03) 4.4 5.7 5.8 5.3 6.2 5.3 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.050 0.040 0.050 0.050 0.030 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) 200 - -- 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 (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CO) <10 -- -- <10 -- -- METHY- LENB BLUE ACTIVE SUB- STANCE (MG/L) 280 100 20 20 tO.10 <0.10 <0.010 <0.010 0.09 0.02 406 RIO GRANDS DB ANASCO BASIN 50141500 LAGO GUAYO NEAR CASTANER, PR LOCATION.--Lat 18O 12'46", long 66O50'06", Hydrologic Unit 21010003, at Guayo 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 km 1 ). 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 ft3/s (855 m?/s) 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, 1461.18 ft (445.37 m), May 29; minimum elevation recorded 1431.18 ft (436.22 m), Nov. 24. Capacity Table (based on data from Puerto Rico Water Resources Authority) Elevation, in feet DAY OCT 1415 1449 NOV Contents, in acre-feet 3,960 10,660 Elevation, in feet 1460 1465 Contents, in acre-feet ELEVATION (FEET NGVD), WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY OBSERVATION AT 24iOO VALUES DEC JAN FBB MAR APR MAY JUN 13,550 15,000 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 1455.66 1456.18 1456.62 1457.06 1459.81 1460.25 1460.21 1460.70 1460.16 1460.19 1459.97 1459.55 1459.41 1460.37 1459.62 1459.88 1459.61 1459.44 1459.15 1458.74 1458.12 1457.49 1457.82 1458.87 1459.11 1458.59 1457.88 1456.98 1456.27 1455.75 1455.24 1458.54 1460.70 1455.24 1454.54 1453.66 1452.67 1451.62 1450.52 1449.35 1448.16 1446.92 1445.58 1444.20 1442.84 1441.56 1441.75 1441.11 1440.39 1439.32 1437.99 1436.96 1435.84 1434.63 1433.40 1432.46 1431.29 A A A A A A A —— 1437.46 1438.33 1438.65 1438.14 1437.59 1436.99 1436.38 1435.75 1435.06 1434.37 1433.65 1432.91 A A A A A A A A A A A A A A A A A A A ___ A A A A 1454.55 1455.03 1455.50 1455.88 1456.29 1456.71 1457.07 1457.51 1457.88 1458.25 1458.60 1458.93 1459.32 1459.64 1459.93 1460.14 1460.18 A A A A A A A 1460.46 1460.06 1460.08 ___ 1459.46 1459.46 1459.73 1458.99 1458.23 1457.49 1456.63 1455.34 1455.51 1455.66 1455.00 1453.91 1453.10 1453.43 1452.35 1451.41 1451.81 1452.14 1452.24 1452.04 1452.01 1452.21 1452.24 1452.17 1451.71 A 1451.27 1451.29 —— ___ ___ 1451.05 1450.32 1449.92 1449.46 1449.75 A 1449.11 1449.46 1449.71 1449.99 1450.09 1449.47 1449.72 1449.96 1449.47 1449.25 1449.48 1449.72 1449.95 1450.20 1450.42 1450.64 1450.83 1451.07 1451.30 1451.55 1452.63 1453.17 1453.45 1453.69 1453.88 ___ 1454.05 1454.25 1454.45 1454.64 1454.78 1454.96 1454.97 1455.19 1455.46 1455.70 1456.31 1457.36 1457.80 1461.13 1460.37 1459.90 1460.01 1458.57 1458.48 1458.38 1457.63 1456.83 1456.30 1456.30 1456.62 1456.87 1456.26 1456.12 1457.87 1459.99 --- 1456.92 1461.13 1454.05 1461.09 1460.92 1460.42 1459.85 1459.75 1460.40 1460.24 1460.32 1460.38 1459.96 1459.80 1459.85 1459.35 1459.34 1458.70 1458.37 1457.63 1456.77 1456.05 1455.60 1455.91 1454.64 1453.42 1453.39 1453.71 1456.87 1460.15 1460.66 1460.83 1460.67 1460.16 1458.55 1461.09 1453.39 1459.44 1459.63 1459.31 1458.97 1458.70 1458.64 1458.39 1458.42 1458.80 1459.49 1458.87 1458.17 1458.15 1457.17 1456.60 1455.83 1455.69 1456.24 1458.58 1459.47 1458.92 1458.25 1458.13 1458.00 1457.70 1456.84 1456.02 1455.34 1453.89 1452.19 --- 1457.66 1459.63 1452.19 1451.67 1450.53 1448.47 1448.05 1447.65 1446.72 1446.36 1445.59 A A A A A A A A 1441.55 1441.83 1440.41 1438.50 1437.97 1437.63 1438.10 1438.61 1439.04 1439.47 1439.91 1439.86 1440.21 1440.58 1439.99 ___ ___ 1440.34 1439.74 1440.06 1440.39 1440.17 1440.17 1440.51 1439.64 1438.33 1436.83 1435.22 1433.18 A A A A A A A A A A A 1432.72 1433.14 1433.56 1434.63 1436.61 1437.71 1438.38 1438.92 ___ 1439.60 1439.87 1439.37 1440.48 1441.12 1442.17 1442.84 1443.02 1443.42 1443.04 1442.69 1443.50 1444.10 1444.42 1444.22 1444.22 1444.09 1444.25 1446.33 1447.16 1447.67 1447.87 1446.77 1447.40 1446.60 1447.21 1450.04 1451.51 1451.84 1452.40 --- 1444.97 1452.40 1439.37 A No gage-height record RIO GRANDB DB ANASCO BASIN +O7 50143000 RIO GRANDB DB ANASCO NEAR LARES, PR WATER-QUALITY RECORDS LOCATION.—Lat 18°15'26", long 66055'00", at bridge on Highway 124, 0.7 mi (1.1 km) downstream from confluence of Rio Blanco and Rio Prieto, and 3.7 mi (6.0 km) southwest of Lares plaza. DRAINAGE AREA.--26.3 mi' (68.1 km1 ) this does not include 36.2 mi' (93.8 km1 ) which contributes only dur- ing high floods, and 3.5 mi 1 (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 1992 TO SEPTEMBER 1993 DATE OCT 1992 30... DEC 16... FBB 1993 23... APR 27... JUN 15... SBP 09... TIME 0850 0920 0930 1050 0850 1400 DIS- CHARGE, INST. CUBIC FEET PER SECOND 171 41 20 36 54 45 SPE- CIFIC CON- DUCT- ANCE (0S/CM) 234 292 321 213 303 285 PH WATER WHOLE FIELD (STAND- ARD UNITS) 6.9 7.6 8.2 7.8 7.8 7.3 TEMPER- ATURE WATER (DBG C) 23.0 21.0 21.5 24.5 25.5 27.7 TUR- BID- ITY (NTU) 28 12 1.1 3.2 0.50 15 OXYGEN, DIS- SOLVED (MG/L) 4.1 4.8 6.2 8.8 8.6 8.2 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 48 54 70 107 102 78 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) <10 19 51 29 16 <10 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 3100 K770 260 270 310 3100 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 6100 460 73 K130 820 210 DATE OCT 1992 30... DEC 16... FBB 1993 23... APR 27... JUN 15... SBP 09. .. HARD- NESS TOTAL (MG/L AS HARD- NESS NONCARB CALCIUM WH WAT TOT FLD DIS- SOLVED MG/L AS (MG/L MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L 82 2 18 120 8 33 70 1 27 (MG/L CAC03) CAC03 AS CA) AS MG) AS NA) 6.0 9.1 9.3 11 8.2 13 SODIUM AD- SORP- TION RATIO POTAS- SIUM, DIS- SOLVED AS K) 0.5 2.5 0.4 2.1 0.6 1.8 ALKA- LINITY WAT WH TOT FBT SULFIDB FIELD CAC03 92 120 130 110 110 93 TOTAL (MG/L MG/L AS (MG/L SULFATB DIS- SOLVED (MG/L <0.5 10 0.6 22 18 CHLO- RIDE, DIS- SOLVED (MG/L AS S) AS SO4) AS CL) 7.3 11 12 OCT 30 DEC 16 FBB 23 APR 27 JUN 15 SBP 09 K = FLUO- RIDB, DIS- SOLVED DATE (MG/L AS F) 1992 <0.10 ... 1993 ... 0.10 0.20 non- ideal count SILICA, DIS- SOLVED (MG/L AS SI02) 28 — -- 30 -- 22 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 131 -- -- 184 _- 163 SOLIDS, DIS- SOLVED (TONS PER DAY) 60.5 — -- 17.9 -- 19.8 RESIDUE TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) <1 14 2 <1 7 3 NITRO- GEN, NITRO- GEN, NITRO- GEN, NITRATE NITRITE NO2+NO3 TOTAL TOTAL TOTAL (MG/L (MG/L (MG/L AS N) AS N) AS N) 1.27 1.29 1.13 1.65 1.12 2.34 0.030 0.010 0.070 0.050 0.380 0.360 1.30 1.30 1.20 1.70 1.50 2.70 NITRO- NITRO- GEN, GEN, AMMONIA ORGANIC TOTAL TOTAL (MG/L (MG/L AS N) AS N) 0.030 0.050 0.030 0.030 0.260 0.180 0.17 0.55 0.27 0.37 0.44 1.0 408 DATE OCT 1992 30... DEC 16... FBB 1993 23... APR 27... JUN 15... SEP 09... DATE OCT 1992 30... DEC 16... FBB 1993 23.. . APR 27.. . JUN 15... SEP 09... RIO GRANDE DE ANASCO BASIN 50143000 RIO GRANDE DE ANASCO NEAR LARES, PR--Continued WATER-QUALITY DATA, MATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.20 0.60 0.30 0.40 0.70 1.2 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) 1.5 1.6 1.6 2.4 3.6 3.9 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS NO3) 6.6 7.1 8.0 11 17 16 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MN) PHOS- PHORUS TOTAL (MG/L AS P) 0.070 0.040 0.050 0.050 0.040 1.10 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 — — 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- LENB BLUB ACTIVE SUB- STANCE (MG/L) 5000 230 140 30 <0.10 <0.10 <0.010 <0.010 0.02 0.03 RIO GRANDB DB ANASCO BASIN 50144000 RIO GRANDS DB ANASCO NEAR SAN SEBASTIAN, PR 409 LOCATION.--Lat 18°17'05", long 67°03'05", Hydrologic Unit 21010003, on right bank, at downstream side of bridge on Highway 108, 0.4 ml (0.6 km) downstream from Quebrada La Zumbadora, 4.4 ml (7.1 km) northwest of Las Marias, 5.4 ml (8.7 km) southwest of San Sebastian. DRAINAGE AREA.--94.3 mi 1 (244.2 km1 ), does not Include 36.2 ml 1 (93.8 km1 ) which contributes only during high floods, and 3.5 ml 1 (9.1 km1 ) which contributes only part of its storm runoff. HATER-DISCHARGE RECORDS PERIOD OF RECORD.--March 1963 to current year. QAGB.--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 hm3 ). Limited storm runoff is contributed to basin by 3.5 mi 1 (9.1 km1 ) above Rio Tore Diversion dam. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SBP 1 2440 942 2 1490 708 3 864 525 4 445 461 5 595 432 6 1390 393 7 1120 368 8 1630 346 9 1490 328 10 4570 313 11 3880 300 12 1840 292 13 828 328 14 908 883 15 2010 721 16 1240 550 17 2100 370 18 3180 582 19 1710 596 20 907 399 21 647 393 22 643 348 23 1060 454 24 1510 313 25 1210 287 26 744 270 27 573 269 28 491 271 29 622 390 30 2090 427 31 1260 --- TOTAL 45487 13259 MEAN 1467 442 MAX 4570 942 MIN 445 269 AC-FT 90220 26300 CPSM 15.6 4.69 IN. 17.94 5.23 STATISTICS OF MONTHLY MEAN MEAN 674 449 MAX 1467 746 (WY) 1993 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) ANNUAL RUNOFF (INCHES) 10 PERCENT EXCEEDS 50 PERCENT EXCEEDS 90 PERCENT EXCEEDS 333 239 332 232 245 258 201 191 186 181 177 174 211 356 377 209 188 178 178 170 165 166 161 157 155 151 168 152 379 344 177 6791 219 379 151 13470 2.32 2.68 DATA 223 482 1966 103 1992 FOR 160 150 145 143 140 139 137 133 131 128 127 125 124 122 127 123 122 120 118 118 139 163 163 161 162 164 166 165 1160 422 361 5858 189 1160 118 11620 2.00 2.31 FOR HATER 140 215 1970 83.6 1965 668 212 179 158 147 139 135 128 126 125 120 121 124 120 121 118 167 129 121 118 120 113 112 115 151 115 111 111 ... ... ... 4224 151 668 111 8380 1.60 1.67 YEARS 1963 106 161 1981 62.3 1992 105 118 107 104 105 103 102 100 121 108 101 107 94 88 92 88 87 84 80 87 105 80 75 75 86 83 291 385 121 119 202 3603 116 385 75 7150 1.23 1.42 - 1993 98.7 271 1972 54.4 1965 1992 CALENDAR YEAR 136452 373 4570 41 45 270700 3. 53. 867 170 58 Oct 10 Mar 24 Mar 20 95 83 106 86 96 101 79 77 76 73 92 71 179 686 516 510 1210 347 213 364 238 250 308 241 143 468 318 162 134 148 464 336 ... 8092 270 1210 71 16050 2.86 3.19 351 1480 2420 1230 775 1540 1160 558 716 571 298 247 229 213 209 340 236 193 179 190 177 208 275 256 190 1120 2040 2040 1530 3840 1850 26661 860 3840 177 52880 9.12 10.52 723 506 423 378 345 385 319 386 585 446 334 523 548 279 239 245 226 222 319 323 234 212 201 193 186 179 176 478 1050 559 11222 374 1050 176 22260 3.97 4.43 254 216 199 185 177 180 381 390 212 186 170 169 159 170 195 184 149 144 142 185 219 436 177 144 148 333 225 148 136 129 125 6267 202 436 125 12430 2.14 2.47 125 121 117 113 112 125 125 114 305 199 e200 e!20 ellS ellO elOS e350 elOSO e600 e320 e!90 e!70 e!55 elSO 140 153 185 130 361 528 853 466 7907 255 1050 105 15680 2.70 3.12 862 710 491 456 609 372 522 730 616 982 417 313 323 272 251 261 273 1320 1580 714 492 523 459 365 298 325 527 893 570 386 ... 16912 564 1580 251 33540 5.98 6.67 , BY HATBR YEAR (WY) 148 313 1971 49.3 1968 FOR 1993 156283 428 4570 71 81 21300 13. 68 310000 4. 61. 1010 222 111 373 1084 1986 63.7 1967 HATBR YEAR Oct 10 Apr 10 Apr 4 Oct 10 54 Oct 10 Apr 8 54 65 287 815 1979 71.2 1977 279 657 1979 111 1990 HATBR 312 460 189 19400 32 35 140000 33. 31 226200 3. 44. 660 188 74 363 936 1979 152 1967 YEARS 1963 Sep Apr Apr Sep 90 Sep Apr 31 99 609 1422 1984 206 1983 - 1993 1979 1967 16 1975 18 1965 14 1965 16 1975 16 1975 19 1965 e Estimated 410 RIO GRANDS DB ANASCO BASIN 50144000 RIO GRANDB 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 1992 TO SEPTEMBER 1993 WATER-QUALITY DATA DATE OCT 1992 29... FBB 1993 02... APR 29... JUL 22... DATE OCT 1992 29... FBB 1993 02... APR 29... JUL 22... DATE OCT 1992 29... FEB 1993 02... APR 29... JUL 22. .. DATE OCT 1992 29. .. FBB 1993 02... APR 29... JUL 22... TIME 0950 0955 0950 1035 HARD- NESS NONCARB WH WAT TOT FLD MG/L AS CACO3 6 3 7 12 SOLIDS, RESIDUE AT 180 DBG. C DIS- SOLVED (MG/L) 140 135 164 151 ALUM- INUM, DIS- SOLVED (UG/L AS AL) 40 50 60 60 DIS- CHARGE, INST. CUBIC FEET PER SECOND 456 214 137 132 CALCIUM DIS- SOLVED (MG/L AS CA) 26 24 27 26 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 155 145 161 153 ARSENIC DIS- SOLVED (UG/L AS AS) <1 <1 <1 <1 SPE- CIFIC CON- DUCT- ANCE (US /CM) 230 226 245 228 MAGNE- SIUM, DIS- SOLVED (MG/L AS MG) 8.6 8.1 8.7 8.7 SOLIDS, DIS- SOLVED (TONS PER DAY) 191 84 60 55 BARIUM, DIS- SOLVED (UG/L AS BA) 31 32 33 31 PH WATER WHOLE FIELD (STAND- ARD UNITS) 6.7 7.9 7.0 7.4 SODIUM, DIS- SOLVED (MG/L AS NA) 9.0 8.0 9.8 9.8 NITRO- GEN, NO2+NO3 DIS- SOLVED (MG/L AS N) 1.10 1.30 0.750 0.670 BERYL- LIUM, DIS- SOLVED (UG/L AS BE) <0.5 <0.5 <0.5 <0.5 TEMPER- ATURE WATER (DBG C) 27.0 22.5 24.5 28.0 SODIUM AD- SORP- TION RATIO 0.4 0.4 0.4 0.4 NITRO- GEN, AMMONIA DIS- SOLVED (MG/L AS N) 0.010 0.040 0.040 0.090 CADMIUM DIS- SOLVED (UG/L AS CD) <1 <1 <1 <1 TUR- BID- ITY (NTU) 7.8 27 15 4.7 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 1.8 2.1 2.1 2.0 NITRO- GEN, AMMONIA DIS- SOLVED (MG/L AS NH4) 0.01 0.05 0.05 0.12 CHRO- MIUM, DIS- SOLVED (UG/L AS CR) <1 <1 <1 <1 OXYGEN, DIS- SOLVED (MG/L) 7.4 6.7 8.0 4.2 ALKA- LINITY WAT WH TOT FBT FIELD MG/L AS CACO3 100 97 100 100 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) <0.20 0.20 0.20 0.70 COBALT, DIS- SOLVED (UG/L AS CO) <3 <3 <3 <3 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 83 58 92 41 SULFATB DIS- SOLVED (MG/L AS SO4) 8.7 8.8 12 10 PHOS- PHORUS TOTAL (MG/L AS P) 0.040 0.070 0.030 0.030 COPPER, DIS- SOLVED (UG/L AS CU) 1 8 3 2 COLI- FORM, FECAL, 0.7 UM-MF (COLS./ 100 ML) 310 2800 1000 2500 CHLO- RIDE, DIS- SOLVED (MG/L AS CL) 7.4 7.4 9.2 7.5 PHOS- PHORUS DIS- SOLVED (MG/L AS P) 0.030 0.060 0.060 0.030 IRON, DIS- SOLVED (UG/L AS FE) 17 43 22 33 STREP- TOCOCCI FECAL, KF AGAR (COLS. PER 100 ML) 670 2300 340 170 FLUO- RIDB, DIS- SOLVED (MG/L AS F) •(0.10 0.10 <0.10 0.10 PHOS- PHORUS ORTHO, DIS- SOLVED (MG/L AS P) 0.030 0.040 0.020 0.020 LEAD, DIS- SOLVED (UG/L AS PB) <1 <1 5 2 HARD- NESS TOTAL (MG/L AS CACO3) 100 93 100 100 SILICA, DIS- SOLVED (MG/L AS SIO2) 30 25 28 28 PHOS- PHATE, ORTHO, DIS- SOLVED (MG/L AS PO4) 0.09 0.12 0.06 0.06 LITHIUM DIS- SOLVED (UG/L AS LI) <4 <4 <4 <4 K = non- ideal count RIO GRANDE DB ANASCO BASIN 50144000 RIO GRANDE DB ANASCO NEAR SAN SEBASTIAN, PR--CONTINUBD (NATIONAL STREAM-QUALITY ACCOUNTING NETWORK STATION) WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 411 DATE OCT 1992 29... FBB 1993 02... APR 29... JUL 22... MANGA- NESE, DIS- SOLVED (UG/L AS MN) 16 15 15 13 MERCURY DIS- SOLVED (UG/L AS HG) <0.1 <0.1 <0.1 <0.1 MOLYB- DENUM, DIS- SOLVED (UG/L AS MO) <10 <10 <10 <10 NICKEL, DIS- SOLVED (UG/L AS NI) <1 1 1 <1 SELE- NIUM, DIS- SOLVED (UG/L AS SB) <1 <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) 140 120 140 130 VANA- DIUM, DIS- SOLVED (UG/L AS V) <6 <6 <6 <6 ZINC, DIS- SOLVED (UG/L AS ZN) 9 3 <3 6 PARTICLE-SIZE DISTRIBUTION OF SUSPENDED SEDIMENT DATE OCT 1992 29... FEB 1993 02... APR 29... JUL 22... TIME 0950 0955 0950 1035 STREAM- FLOW, INSTAN- TANEOUS (CFS) 456 214 137 132 SEDI- MENT, SUS- PENDED (MG/L) 22.6 57.8 43.1 37.4 SEDI- MENT, DIS- CHARGE, SUS- PENDED (T/DAY) 27.8 33.3 15.9 13.3 SBD. SUSP. SIEVE DIAM. PERCENT FINER THAN .062 MM 88 86 95 94 472 RIO GRANDE OB ANASCO BASIN 50146000 RIO GRANDS DB ANASCO NEAR ANASCO, PR WATER-QUALITY RECORDS LOCATION. --Lat 18°16'00", long 67°08'05", at bridge on Highway 430, 0.2 mi (0.3 km) south of Highway 109 at Bl Bapino and 1.4 mi (2.3 km) east-southeast from Afiasco plaza. DRAINAGE AREA.--139 mi* (360 k»») this does not include 39.7 mi* (102.8 km'), flow is diverted to south coast. PERIOD OP RECORD.—Water years 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 28... DEC 17... FEE 1993 24... APR 28... JUN 16... 3BP 09... TIME 0845 0830 0915 1050 0840 0915 DIS- CHARGE, INST. CUBIC PBBT PBR SECOND B1000 B350 130 194 300 B350 SPE- CIFIC CON- DUCT- ANCE (OS/CM) 225 249 255 248 235 151 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.1 7.2 7.2 7.7 7.1 6.9 TEMPER- ATURE WATER (DBG C) 25.0 22.0 24.0 25.5 26.0 23.1 TUR- BID- ITY (NTH) 42 11 9.0 14 22 38 OXYGEN, DIS- SOLVED (MG/L) 5.0 4.0 5.2 7.7 8.5 8.7 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 59 45 60 92 103 99 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) <10 12 <10 11 10 24 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) 2800 590 82 K1400 K1200 220 STREP- TOCOCCI FECAL, (COLS. PBR 100 ML) K1SOO 290 230 430 K200000 260 DATE OCT 1992 28... DEC 17... FEB 1993 24... APR 28... JUN 16... SEP 09... HARD- NESS TOTAL (MG/L AS CAC03) 250 __ __ 150 __ 210 CALCIUM DIS- SOLVED (MG/L AS CA) 72 54 74 MAGNE- SIUM, DIS- SOLVED (MG/L AS MO) 7.2 " 3.6 6.6 SODIUM, DIS- SOLVED (MG/L AS NA) 15 ~~ ~™ 5.9 ~~ 11 SODIUM AD- SORP- TION RATIO 0.5 -- -- 0.2 -- 0.3 POTAS- SIUM, DIS- SOLVED (MG/L AS K) 1.1 -- — 1.8 — 2.2 ALKA- LINITY WAT WH TOT PET FIELD MG/L AS CACO3 85 110 110 98 80 59 SUXiFTDB TOTAL (MG/L AS S) <0.5 — — <0.5 -- SULFATB DIS- SOLVED (MG/L AS 504) 9.4 __ __ 8.7 __ K 1 CHLO- RIDE, DIS- SOLVED (MG/L AS CL) 26 9.1 * O DATE OCT 1992 28... DEC 17... FBB 1993 24... APR 28... JUN 16.. . SEP 09... FLUO- RIDB, DIS- SOLVED (MG/L AS F) <0.10 __ __ 0.10 __ 0.30 SILICA, DIS- SOLVED (MG/L AS SI02) 6.6 4.2 C 7 SOLIDS, SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 253 171 •*^*» RESIDUE SOLIDS, TOTAL OTTRO- NTPRO- OTTRO- DIS- AT 105 GEM. GEN, QBN, SOLVED DBG. C, NITRATE NITRITE NO2+NO3 (TONS SUS- TOTAL TOTAL TOTAL PER PBNDBD (MG/L (MG/L (MG/L DAY) (MG/L) AS N) AS N) AS N) 90 7 20 5 0.720 1.49 2.29 2.49 1.79 0.09 0.010 0.010 0.010 0.010 0.010 0.010 non-ideal count 0.730 1.50 2.30 2.50 1.80 0.10 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.020 0.220 0.010 0.030 0.010 0.020 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.18 0.68 0.19 0.27 0.19 1.8 Water Resources Data - Puerto Rico and the U.S. Virgin Islands, Water Year 1993 413 RZO ORANDB DB ANASCO BASIN 50146000 RIO QRANDB DB ANASCO NEAR ANASCO, PK--Continued MATBR-QOALITY DATA, HATER YBAR OCTOBBR 1992 TO SBPTBMBBR 1993 DATE OCT 1992 28... DBC 17... FEB 1993 24... APR 28... JON 06... SBP 09... NITRO- GEN, AM- MONIA * ORGANIC TOTAL (MG/L AS N) 0.20 0.90 0.20 0.30 0.20 2.0 NITRO- GEN. TOTAL (MG/L AS N) 2.2 3.3 0.40 0.30 2.0 1.8 NITRO- GEN, TOTAL (MG/L AS NO3) 15 12 15 10 9.7 11 PROS- PBORO8 TOTAL (MG/L AS P) 0.010 0.030 0.010 0.040 0.020 0.020 ARSENIC TOTAL (OG/L AS AS) 1 — I — _. BARI0K, TOTAL RECOV- ERABLE (OG/L AS BA) <100 "" — <100 — __ BORON. TOTAL RECOV- ERABLE (00/L AS B) <10 •• — 20 .. „„ CADMIOH TOTAL RBCOV- BRABLB (00/L AS CO) <1 -• ._ <1 .. CHRO- MXOM, TOTAL RECOV- ERABLE (00/L AS CR) <1 -— „„ <1 „_ COPPER, TOTAL RECOV- ERABLE (OG/L AS CO) <10 -• _— <10 ^^ DATB OCT 1992 28... DBC 17... FBB 1993 24... APR 25... JON 16... SBP 09... IRON. TOTAL RECOV- ERABLE (OG/L AS FB) LEAD, TOTAL RECOV- ERABLE (OG/L AS PB) MANGA- NESE, TOTAL RECOV- ERABLE (OG/L AS MN) MBRCORY TOTAL RECOV- ERABLE (OG/L AS BO) SBLB- NIUM, TOTAL (00/L AS SB) SILVER, TOTAL RECOV- ERABLE (OG/L AS AG) ZINC, TOTAL RECOV- ERABLE (00/L AS ZN) CYANIDE TOTAL (MG/L AS CM) PHENOLS TOTAL (00/L) MBTHY- LBNB BLOB ACTIVE 8OB- STANCB (MO/L) 180 2SO 30 50 0.10 0.10 <0.010 <0.010 0.05 0.02 414 THIS PAGE WAS LEFT BLANK INTENTIONALLY Drainage boundary uncertain LARES EXPLANATION ±1478 SURFACE-WATER STATION AND NUMBER T1476 QUALITY-OF-WATER STATION AND NUMBER A 33 WELL AND WELL NUMBER -- Map area 0123456 KILOMETERS 01234 MILES 01 Figure 27.--R(o Culebrinas basin. " RIO CDLEBRIHAS BASIN 50147600 RIO CDLEBRINAS NEAR SAN SEBASTIAN, PR HATER-QUALITY RECORDS LOCATION.—Lat 18°20'51", long 67°02'40", at bridge on Highway 423, 1.3 mi (2.1 km) south of Quebrada El Salto Bridge on Highway 111, and 2.1 mi (3.4 km) west of Central La Plata. DRAINAGE AREA.--58.2 mi 1 (150.7 km1 ). PERIOD OF RECORD.—Water years 1979 to current year. HATER-QUALITY DATA, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 27... DEC 16... FEB 1993 23... APR 27... JUN 15... SEP 09... TIME 0920 1120 1130 1320 1045 1020 DIS- CHARGE, INST. CUBIC FEET PER SECOND 174 74 37 122 97 231 SPE- CIFIC CON- DUCT- ANCE (US/CM) 290 278 289 374 265 299 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.5 7.4 8.5 7.6 7.4 7.4 TEMPER- ATURE HATER (DBG C) 25.0 23.5 21.5 24.5 26.0 23.3 TUR- BID- ITY (NTU) 120 18 2.7 12 21 240 OXYGEN, DIS- SOLVED (MG/L) 6.8 7.6 9.5 7.8 8.0 7.8 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 81 90 105 92 98 81 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) <10 11 31 33 <10 13 COLI- FORM, FECAL, 0.45 UM-MF (COLS./ 100 ML) K1SOOO K17000 K140 2300 5100 39000 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 3100 2100 K160 220 K1800 K110000 DATE OCT 1992 27... DEC 16... FEB 1993 23... APR 27. .. JUN 15... SEP 09... HARD- HARD- NESS NESS NONCARB CALCIUM TOTAL WH HAT DIS- (MG/L TOT FLD SOLVED AS MG/L AS (MG/L CAC03) CAC03 120 8 42 180 0 63 130 3 44 MAGNE- SIUM, SODIUM, DIS- DIS- SOLVED SOLVED (MG/L AS CA) AS MG) AS NA) 3.8 6.6 6.3 12 4.3 8.2 SODIUM AD- SORP- TION (MG/L RATIO 0.3 0.4 0.3 ALKA- POTAS- LINITY SIUM, HAT WH DIS- TOT FET SULFIDB SOLVED FIELD TOTAL (MG/L MG/L AS (MG/L AS K) 2.0 2.2 3.7 CAC03 130 150 110 190 100 110 CHLO- SULFATE RIDE, DIS- DIS- SOLVED SOLVED (MG/L (MG/L AS S) AS SO4) AS CL) <0.5 14 8.0 0.6 18 9.8 13 7.9 SOLIDS, RESIDUE DATE OCT 1992 27... DEC 16... FEB 1993 23... APR 27... JUN 15... SEP 09... FLUO- RIDE, DIS- SOLVED (MG/L AS F) <0.10 -- -- 0.10 -- 0.20 SILICA, DIS- SOLVED (MG/L AS SIO2) 14 — -_ 20 -- 16 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 210 -- -- 232 -- 176 SOLIDS, DIS- SOLVED (TONS PER DAY) 98.7 — — 76.4 — 110 TOTAL AT 105 DBG. C, SUS- PENDED (MG/L) 29 <1 6 13 33 92 NITRO- GEN, NITRATE TOTAL (MG/L AS N) 1.18 1.32 0.950 1.04 1.02 1.12 NITRO- GEN, NITRITE TOTAL (MG/L AS N) 0.020 0.080 0.050 0.060 0.080 0.080 NITRO- GEN, N02+NO3 TOTAL (MG/L AS N) 1.20 1.40 1.00 1.10 1.10 1.20 NITRO- GEN, AMMONIA TOTAL (MG/L AS N) 0.040 0.080 0.480 0.150 0.120 0.110 NITRO- GEN, ORGANIC TOTAL (MG/L AS N) 0.16 0.42 0.82 0.65 0.38 0.39 non-ideal count DATE OCT 1992 27... DEC 16... FBB 1993 23.. . APR 27... JUN 15... SEP 09... DATE OCT 1992 27... DEC 16... FBB 1993 23... APR 27... JUN 15... SEP 09... RIO CULEBRINAS BASIN 50147600 RIO CULEBRINAS NEAR SAN SEBASTIAN, PR—Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 417 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 0.20 0.50 1.3 0.80 0.50 0.50 IRON, TOTAL RECOV- ERABLE (UG/L AS FB) NITRO- GEN, TOTAL (MG/L AS N) 1.4 1.9 2.3 1.6 1.9 1.7 LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) NITRO- GEN, TOTAL (MG/L AS N03) 6.2 8.4 10 8.6 7.1 7.5 MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MM) PHOS- PHORUS TOTAL (MG/L AS P) 0.050 0.110 0.130 0.040 0.090 0.080 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 -- -- 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) <1 -- -- <1 -- -- PHENOLS TOTAL (UG/L) COPPER, TOTAL RECOV- ERABLE (UG/L AS CU) <10 — — <10 — -- MBTHY- LENB BLUB ACTIVE SUB- STANCE (MG/L) 3500 590 100 70 <0.10 <0.10 <0.010 <0.010 0.01 0.04 418 RIO CULEBRINAS BASIN 50147800 RIO CULEBRINAS AT HIGHWAY 404 NEAR MOCA, PR LOCATION.--Lat 18«21'42", long 67«05'33 11 , 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 OF RECORD.--July 1967 to current year. GAGE.--Water-stage recorder. Elevation of gage is 45 ft (14 m), from topographic map. REMARKS.--Records poor. Gage-height and precipitation satellite telemetry at station. DISCHARGE, CUBIC FEET PER SECOND, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FBB MAR APR MAY JUN JUL AUG SEP 1 e!450 e500 2 e880 e400 3 e520 e300 4 e270 e260 5 e360 e240 6 e840 e230 7 e680 e200 8 e980 el90 9 e900 el80 10 e2570 e!70 11 e2300 el60 12 ellOO e!60 13 e500 e!90 14 e550 e500 15 e!200 e400 16 e720 e290 17 e!400 e210 18 elSOO e340 19 e720 e340 20 e400 e230 21 e330 e230 22 e310 e200 23 e660 e260 24 e880 e!80 25 e540 e!60 26 e400 el50 27 e320 e!50 28 e280 elSO 29 e360 e230 30 e!200 e250 31 e660 —— TOTAL 26080 7450 MEAN 841 248 MAX 2570 500 MIN 270 150 AC-FT 51730 14780 CFSM 11.8 3.49 IN. 13.63 3.89 STATISTICS OF MONTHLY MEAN MEAN 633 350 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 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 elSO e!40 e!90 e!30 el40 elSO e!20 ellO elOO e98 e96 e95 elSO e210 e220 el20 ellO el08 el04 el07 e!02 elOO elOO e97 e95 e90 886 e98 e88 e220 e200 3954 128 220 86 7840 1.79 2.07 DATA 145 424 1982 72.1 1992 FOR elOO e91 e86 e83 e82 e84 e81 e82 e78 e77 e76 e75 e72 e72 e7l e68 e68 elOO e71 e68 e69 e65 e66 e65 e64 e63 e63 e63 e260 e!20 e350 2833 91.4 350 63 5620 1.28 1.48 e200 el70 e!20 e96 e86 e80 e76 e73 e69 e70 e70 e67 e74 e90 e74 e69 66 63 63 63 66 61 60 65 68 64 61 60 ___ ___ --- 2244 80.1 200 60 4450 1.13 1.17 FOR WATER YEARS 1967 77.7 151 1971 51.2 1979 70.2 243 1981 37.0 1992 56 59 58 57 55 54 50 46 46 48 59 64 78 49 44 43 46 45 42 41 49 47 43 40 76 114 107 56 55 88 119 1834 59.2 119 40 3640 .83 .96 - 1993 65.6 319 1981 30.4 1979 1992 CALENDAR YEAR 109356 299 3090 25 28 216900 4.20 57.14 682 170 36 May 23 Mar 23 Mar 19 111 115 123 77 66 85 118 65 74 56 723 295 134 611 300 459 362 2310 463 323 1370 372 212 223 e!60 e260 e!30 ellO el20 e360 --- 10187 340 2310 56 20210 4.77 5.32 e260 e280 e!200 e!900 e940 e600 el200 e900 e450 e580 e450 e230 e200 elSO e!70 e!60 e270 elSO 188 191 382 2070 1550 296 e257 180 164 625 241 1020 323 17607 568 2070 150 34920 7.98 9.20 211 167 170 372 221 152 145 129 201 165 140 150 e275 180 139 128 107 e350 e300 e!70 149 128 118 118 151 108 100 96 397 143 5380 179 397 96 10670 2.52 2.81 89 81 79 75 73 69 68 68 67 62 61 65 62 70 282 133 74 67 76 72 64 122 117 88 83 405 159 87 75 69 64 3026 97.6 405 61 6000 1.37 1.58 62 60 56 53 53 78 66 107 91 78 96 70 57 54 52 160 499 261 122 90 79 73 67 156 1510 206 103 259 186 303 203 5310 171 1510 52 10530 2.41 2.77 147 105 89 83 265 126 1390 640 252 2000 262 181 156 147 125 443 485 264 1640 270 172 161 156 146 200 149 130 1050 616 1580 13430 448 2000 83 26640 6.29 7.02 , BY WATER YEAR (WY) 143 621 1986 26.4 1970 FOR 1993 99335 272 2570 40 44 15000 40 197000 3. 51. 631 130 61 475 2054 1986 96.7 1973 WATER YEAR Oct 10 Mar 24 Mar 18 Oct 10 Mar 24 82 90 381 769 1984 82.7 1974 312 847 1979 91.8 1983 WATER 294 457 179 13300 19 20 69000 36. 16 213300 4. 56. 601 138 42 337 831 1979 119 1970 YEARS 1967 - Oct 21 Apr 16 Apr 13 Sep 16 60 Sep 16 Apr 17 13 17 517 1350 1978 145 1986 1993 1986 1977 1972 1979 1979 1975 1975 1979 e Estimated 419 RIO C0LEBRINAS BASIN 50149100 RIO CULEBRINAS NEAR AGUADA, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°24'03", long 67°09'40", at bridge on Highway 2, and 2.3 mi (3.7 km) northeast of Aguada plaza. DRAINAGE AREA.--97.0 mi* (251.2 km1 ). PERIOD OF RECORD.--Water years 1958, 1970 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DATE OCT 1992 28... DEC 17... FBB 1993 24. .. APR 28... JUN 16... SEP 09... TIME 1150 1035 1025 0900 1025 0755 DIS- CHARGE, INST. CUBIC FEET PER SECOND 851 169 50 457 269 600 SPE- CIFIC CON- DUCT- ANCE (US/CM) 270 328 350 354 426 245 PH WATER WHOLE FIELD (STAND- ARD UNITS) 7.4 7.2 7.6 7.2 7.8 6.9 TEMPER- ATURE WATER (DEG C) 26.0 23.5 25.0 24.0 25.5 24.1 TUR- BID- ITY (NTU) 207 21 5.3 110 90 690 OXYGEN, DIS- SOLVED (HG/L) 3.0 3.5 3.4 6.0 7.1 5.3 OXYGEN, DIS- SOLVED (PER- CENT SATUR- ATION) 36 40 40 70 85 72 OXYGEN DEMAND, CHEM- ICAL (HIGH LEVEL) (MG/L) 34 <10 25 50 18 27 COLI- FORM, FECAL, 0.45 UM-MP (COLS . / 100 ML) 45000 2700 K60000 36000 7200 K280000 STREP- TOCOCCI FECAL, (COLS. PER 100 ML) 37000 K1800 K60000 K60000 5300 22000 DATE OCT 1992 28. .. DEC 17... FEB 1993 24. .. APR 28... JUN 16... SEP 09... 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 POTAS- SIUM, DIS- SOLVED (MG/L ALKA- LINITY WAT WH TOT FET FIELD MG/L AS CACO3) CACO3 AS CA) AS MG) AS NA) 130 2 47 160 16 55 100 0 33 5.5 7.2 5.3 9.4 5.4 6.7 AS K) 0.2 3.9 0.3 3.7 0.3 3.6 CACO3 150 140 180 140 130 94 SULFATB SULFIDB DIS- TOTAL SOLVED (MG/L (MG/L <0.5 15 <0.5 16 16 CHLO- RIDE, DIS- SOLVED (MG/L AS S) AS S04) AS CL) 8.9 12 7.8 SOLIDS, DATE OCT 1992 28.. . DEC 17... FBB 1993 24... APR 28... JUN 16.. . SEP 09... FLUO- RIDE, DIS- SOLVED (MG/L AS F) <0.10 -- -- 0.10 -- <0.10 SILICA, DIS- SOLVED (MG/L AS SI02) 15 -- -- 18 -- 13 SUM OF CONSTI- TUENTS, DIS- SOLVED (MG/L) 193 -- -- 211 -- 151 RESIDUE SOLIDS, TOTAL NITRO- NITRO- NITRO- NITRO- NITRO- DIS- AT 105 GEN, GEN, GEN, GEN, GEN, SOLVED DEG. C, NITRATE NITRITE NO2+NO3 AMMONIA ORGANIC (TONS SUS- TOTAL TOTAL TOTAL TOTAL TOTAL PER FENCED (MG/L (MG/L (MG/L (MG/L (MG/L DAY) (MG/L) AS N) AS N) AS N) AS N) AS N) 254 320 13 225 490 388 0.670 0.870 0.570 0.750 0.670 0.870 0.040 0.030 0.030 0.050 0.030 0.030 0.710 0.900 0.600 0.800 0.700 0.900 0.030 0.100 0.130 0.170 0.100 0.110 0.97 0.40 0.27 0.73 0.80 0.19 non-ideal count 420 DATE OCT 1992 28... DEC 17.. . FBB 1993 24... APR 28... JUN 16... SEP 09... RIO CULBBRINAS BASIN 50149100 RIO CULBBRINAS NEAR AGOADA, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 NITRO- GEN, AM- MONIA + ORGANIC TOTAL (MG/L AS N) 1.0 0.50 0.40 0.90 0.90 0.30 NITRO- GEN, TOTAL (MG/L 1.7 1.4 1.1 1.7 1.6 1.2 NITRO- PHOS- GBN, PHORUS TOTAL TOTAL (MG/L (MG/L AS N) AS NO3) AS P) 7.6 6.2 4.3 7.1 7.5 5.3 BARIUM, BORON, CADMIUM TOTAL TOTAL TOTAL ARSENIC RBCOV- RECOV- RECOV- TOTAL ERABLB BRABLB BRABLB (UG/L (UG/L (UG/L (UG/L 0.240 0.090 0.140 0.100 0.060 0.220 AS AS) AS BA) AS B) <100 <100 30 30 CHRO- MIUM, TOTAL RECOV- ERABLE (UG/L COPPER, TOTAL RECOV- ERABLE (UG/L AS CD) AS CR) AS CU) <1 20 <10 DATE OCT 1992 28.. . DEC 17... FBB 1993 24.. . APR 28... JUN 16.. . SEP 09.. . IRON, TOTAL RECOV- ERABLE (UG/L AS FB) LEAD, TOTAL RECOV- ERABLE (UG/L AS PB) MANGA- NESE, TOTAL RECOV- ERABLE (UG/L AS MM) 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) 7400 5200 370 380 <0.10 <0.10 <1 <1 <1 <1 30 <0.010 20 <0.010 0.04 0.01 PESTICIDE ANALYSES DATE TIME JUL 1993 07... 0945 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- BLDRIN TOTAL (UG/L) BNDO- SULFAN, TOTAL (UG/L) <0.010 <0.010 <0.010 <0.010 <0.010 DATE JUL 1993 07... ENDRIN WATER UNFLTRD REC (UG/L) <0.010 BTHION, TOTAL (UG/L) HBPTA- CHLOR, TOTAL (UG/L) HEPTA- CHLOR BPOXIDE TOTAL (UG/L) LINDANE TOTAL (UG/L) <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 MIRBX, TOTAL (UG/L) <0.01 DATE JUL 1993 07... 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 <0.01 0.12 <0.01 <0.01 <0.01 CULBBRA, PR 50214500 QUBBRADA RESACA NEAR MONTE RBSACA, CULBBRA, PR 421 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) couthweit of Monte Reiaca, and 1.0 mi (1.6 km) eait of Bahia Tamarindo. DRAINAGE AREA.--0.23 mi' (0.60 km'). HATER-STAGE RECORDS PERIOD OF RECORD.—October 1991 to current year. GAGE.—Water-stage recorder. Elevation of gage i» 66 ft (20 m), from topographic map. REMARKS.—Gage-height and precipitation satellite telemetry at station. All gage-height* of 5.30 ft or lower are considered zero flow. EXTREMES FOR PERIOD OF RECORD.—Maximum gage-height 7.49 ft (2.283 m), May 26; minimum, 4.68 ft (1.426 m), Aug. 9. EXTREMES FOR CURRENT YEAR.—Maximun gage-height 6.96 ft (2.121 m), Dec. 30; ndnimun, 4.68 ft (1.426 m), Aug. 9. DAY OCT GAGE HEIGHT, FEET, HATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES NOV DEC JAN FEB MAR APR MAY 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 .82 .82 .83 .83 .83 .83 .84 .84 .84 .84 .84 .84 .84 .84 .83 .84 .84 .83 .83 .84 .83 .83 .84 .86 .85 .86 .87 .87 .88 .88 .89 .84 .89 .82 .91 ! .91 .97 .41 .12 .92 .91 .90 .90 .89 .90 .90 .89 .92 .90 .90 .91 .90 .90 .96 .92 .91 .90 .90 .91 1.91 5.18 5.16 5.10 ! 5.39 1.97 < 5.41 1.89 < >.05 ! .99 .96 .91 .91 .91 .91 .91 .93 .91 .91 .91 .91 .94 .92 .89 .89 .90 .90 .90 .90 .90 .90 .91 .91 .91 .90 .89 5.25 5.59 5.09 1.96 < 5.59 ! 1.89 < i.Ol .98 .96 .93 .91 .89 .86 .85 .85 .85 .85 .85 .85 .85 .86 .86 .84 4 .82 .81 .81 .80 .82 .84 .85 .85 .84 .83 .83 .82 .82 .82 1.86 S.01 4 1.80 < .84 .84 .84 .84 .84 .83 .83 .82 .81 .81 .81 .80 .82 .83 .82 .82 .40 .85 .85 .86 .88 .88 .87 .87 .87 .87 .86 .87 5.40 3.40 1.80 .87 .88 .88 .89 .89 .89 .88 .88 .87 .87 .86 .86 .85 .85 .86 .86 .87 .88 .87 .87 .87 .86 .86 .87 .88 .87 .86 .85 .85 .85 .84 .87 .89 .84 .85 .84 .84 .83 .84 .84 .82 .78 .80 .81 .80 .79 .82 .86 .86 .84 .88 .81 .82 .82 .79 .76 .75 .76 .76 .75 .79 .79 .78 .85 —— .81 .88 .75 .82 .81 .81 .80 .81 .81 .82 .84 .15 .86 .86 .86 .86 .84 .82 .81 .80 .78 .76 .78 .80 .78 .78 .77 .78 .77 .75 .74 .73 .71 ___ ___ JUN JUL AUG SEP .90 .90 .91 .90 .91 .90 .91 .90 .89 .90 .92 .91 .92 .93 .93 .93 .93 .93 .94 .94 .94 .94 .95 .93 .93 .94 .95 .95 .95 .95 .94 .92 .95 .89 .95 .96 .96 .96 .81 .73 .73 .73 .71 .69 .69 .69 .69 .69 .69 .69 .70 .70 .70 .70 .70 .70 .70 .70 .71 .71 .71 .71 .71 .71 .71 .74 .96 .69 .72 .72 .72 .72 .72 .72 .72 .73 .73 .73 .73 .73 .73 .73 .73 .74 .74 .74 .74 .74 .74 .74 .75 .75 .75 .75 .75 .75 .75 .76 - — .74 .76 .72 CAL YR 1992 MEAN 4.90 MAX 5.72 MIN 4.79 422 COLEBRA, PR 50215000 DRAINAGE CANAL AT COLEBRA 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 1 (0.20 km 1 ). WATER-STAGE RECORDS PERIOD OF RECORD.--October 1991 to current year (discontinued). GAGE.—Hater-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 10.25 ft or lower are considered zero flow. EXTREMES FOR PERIOD OF RECORD.--Maximum gage-height recorded, 10.52 ft (3.206 m), Apr. 21, 1993; minimum, 9.73 ft (2.966 m), Mar. 6, 1992. EXTREMES FOR CURRENT YEAR.--Maximum gage-height recorded, 10.52 ft (3.206 m), Apr. 21; minimum, 10.11 ft (3.082 m), Jan. 8. GAGE HEIGHT, FEET, WATER YEAR OCTOBER 1992 TO SEPTEMBER 1993 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY OUN JUL AUG SEP —— 10.25 10.28 10.28 —— 10.25 10.29 10.27 10.33 10.31 10.27 10.30 10.31 10.30 10.28 10.31 10.34 —— 10.28 10.31 10.29 —— 10.28 10.30 10.22 10.26 10.30 10.22 —— 10.27 10.30 10.23 10.28 10.30 10.24 —— 10.28 10.31 10.26 —— 10.29 10.31 10.26 10.28 10.31 10.26 —-- 10.28 10.31 10.25 10.28 10.31 10.26 10.28 10.30 10.33 —— 10.28 10.28 10.34 —— 10.27 10.28 10.32 10.28 10.29 10.30 10.28 10.30 10.21 10.27 10.30 10.21 —— 10.26 10.29 10.21 —— 10.32 10.27 10.21 —— 10.31 10.28 10.21 10.26 10.28 10.21 —— 10.28 10.28 10.23 10.26 10.29 10.24 —-- 10.26 10.27 10.23 —— 10.26 10.27 10.23 —— 10.27 10.27 10.22 —— 10.28 10.28 —— —— 10.28 10.29 10.25 10.33 10.31 10.34 10.25 10.27 10.21 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 KIN 10.27 10.28 10.27 10.27 10.27 10.29 10.28 10.30 10.30 10.29 10.29 10.26 10.26 10.25 10.24 10.25 10.28 10.29 10.26 10.25 10.24 10.25 10.25 10.26 10.27 10.28 10.28 10.22 10.23 10.24 10.25 10.27 10.30 10.22 10.25 10.25 10.26 10.27 10.25 10.25 10.24 10.24 10.25 10.25 10.24 10.25 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 10.23 --- 10.25 10.27 10.23 10.23 10.23 10.23 10.23 10.27 10.26 10.26 10.26 10.26 10.26 10.26 10.26 10.26 10.25 10.24 10.20 10.19 10.14 10.15 10.14 10.14 10.17 10.14 10.19 10.15 10.26 10.21 10.24 10.24 10.25 10.25 10.22 10.27 10.14 10.25 10.25 10.25 10.20 10.22 10.18 10.13 10.13 10.14 10.16 10.15 10.15 10.15 10.15 10.15 10.17 10.16 10.16 10.18 10.17 10.17 10.16 10.16 10.16 10.16 10.17 10.16 10.14 10.15 10.16 10.16 10.17 10.25 10.13 10.16 10.16 10.16 10.15 10.16 10.16 10.16 10.16 10.16 10.17 10.18 10.18 10.18 10.17 10.18 10.19 10.20 10.21 10.21 10.24 10.22 10.21 10.22 10.22 10.22 10.23 10.25 10.26 ___ ___ — - 10.19 10.26 10.15 10.22 10.21 10.21 10.20 10.21 10.21 10.21 10.22 10.21 10.21 10.20 10.21 10.20 10.21 10.21 10.22 10.21 10.22 10.22 10.22 10.22 10.22 10.24 10.21 10.20 10.20 10.20 10.20 10.20 10.20 10.21 10.21 10.24 10.20 10.21 10.22 10.22 10.22 10.26 10.27 10.27 10.27 10.27 10.28 10.28 10.28 10.27 10.27 10.27 10.27 10.27 10.28 10.28 10.29 10.29 10.28 10.29 10.27 10.27 10.27 10.27 10.28 10.28 10.26 —— 10.27 10.29 10.21 10.24 10.23 10.21 10.22 10.23 10.23 10.25 10.26 10.23 10.23 10.22 10.21 10.21 10.22 10.23 10.23 10.21 10.21 10.22 10.21 -__ ___ ___ ___ -__ ___ ___ ___ —— VIEQUES, PR 50231000 QUEBRADA COFRBSI TRIBUTARY NEAR ISABEL SEGUNDA, VIEQUES, 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. 423 DRAINAGE AREA.--0.28 mi' (0.72 km 1 ). WATER-STAGE RECORDS PERIOD OF RECORD.—July 1991 to current year. 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 PERIOD OF RECORD.--Maximum gage-height, 11.20 ft (3.414 m), July 23, 1993; minimum, 7.69 ft (2.344 m), Aug. 28, 1992. EXTREMES FOR CURRENT YEAR.--Maximum gage-height, 11.20 ft (3.414 m), July 23; minimum, 7.94 ft (2.420 m), Apr. …