Diaz et al 2002 Water resources data Puerto Rico and the U.S. Virgin Islands water year 2002

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Date: 2002
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U.S. Department of the Interior U.S. Geological Survey Prepared in cooperation with the Commonwealth of Puerto Rico, the Government of the U.S. Virgin Islands, and with other agencies Water Resources Data Puerto Rico and the U.S. Virgin Islands Water Year 2002 By Pedro L. Díaz, Zaida Aquino, Carlos Figueroa-Alamo, René García, and Ana V. Sánchez Water-Data Report PR-02-1 U.S. DEPARTMENT OF THE INTERIOR GALE A. NORTON, Secretary U.S. GEOLOGICAL SURVEY Charles G. Groat, Director For additional information on the water-resources investigation programs in Puerto Rico and the U.S. Virgin Islands write to: Chief, Caribbean District, Water Resources Division U.S. Geological Survey GSA Center, Suite 400-15 651 Federal Drive Guaynabo, Puerto Rico 00965 Telephone: (787) 749-4346 2004 III 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 the U.S. Geological Survey policy and established guidelines, the following personnel contributed significantly to the collection, processing, and tabulations of the data: José M. Agis Rafael Peña-Cortéz George Arroyo Ronald T. Richards Ramòn Carrasquillo Carlos C. Rodríguez Gregory Cherry Julio A. Rodríguez Iris M. Concepción Miguel A. Rodríguez José A. Concepción Rafael M. Rodríguez Israel Cruz Manuel Rosario Teresa Dopazo José René Sánchez Angel G. Ferrer Luis Santiago-Rivera Wilfredo García Carlos Santos Hector Guardiola Luis Soler Evelyn S. Guevara Elliot M. Sosa Senén Guzmán-Ríos Angel Torres Felipe Hernández Heriberto Torres-Sierra Sandra Lagares James Torres Christian D. López Sigfredo Torres-González José Merced Ricardo J. Vachier Carlos Narvaez Ahmed Valencia Nilo Peña Luis Vega Francisco Maldonado prepared the illustrations and and Ruth I. Guzmán typed the text of the report and was mainly responsible for the assemble of the book using Automated Annual Report (AAR) Scripts for Surface-Water Discharge and Water-Quality Stations. 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 Pedro L. Díaz, Caribbean District Chief, San Juan, Puerto Rico. REPORT DOCUMENTATION PAGE Form Approved OMB No. 0704-0188 NSN 7540-01-280-5500 Standard Form 298 (Rev. 2-89) Prescribed by ANSI Std 239-18 298 102 4. TITLE AND SUBTITLE 5. FUNDING NUMBERS 6. AUTHOR(S) 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING / MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. AGENCY REPORT NUMBER 11. SUPPLEMENTARY NOTES 12a. DISTRIBUTION / AVAILABILITY STATEMENT 12b. DISTRIBUTION CODE 13. ABSTRACT (Maximum 200 words) 14. SUBJECT TERMS 15. NUMBER OF PAGES 16. PRICE CODE 17. SECURITY CLASSIFICATION OF REPORT 18. SECURITY CLASSIFICATION OF THIS PAGE 19. SECURITY CLASSIFICATION OF ABSTRACT 20. LIMITATION OF ABSTRACT 1. AGENCY USE ONLY (Leave blank) 2. REPORT DATE 3. REPORT TYPE AND DATES COVERED SPONSORING / MONITORING Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden, to Washington Headquarters Services, Directorate for Information Operations and Reports, 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302, and to the Office of Management and Budget, Paperwork Reduction Project (0704-0188), Washington, DC 20503. April 2004 Annual - October 1, 2001 to September 30, 2002 Water Resources Data for Puerto Rico and the U.S. Virgin Islands Water Year 2002 Pedro L. Díaz, Zaida Aquino, Carlos Figueroa-Alamo, René García, Ana V. Sánchez U.S. Geological Survey, Water Resources Division GSA Center, 651 Federal Drive, Suite 400-15 Guaynabo, Puerto Rico 00965 USGS-WDR-PR-02-1 U.S. Geological Survey, Water Resources Division GSA Center, 651 Federal Drive, Suite 400-15 Guaynabo, Puerto Rico 00965 USGS-WDR-PR-02-1 Prepared in cooperation with the Commonwealth of Puerto Rico, the Government of the U.S. Virgin Islands, and other agencies. NO RESTRICTION ON DISTRIBUTIONS Water resources data for surface-water, quality-of-water, and ground-water records for the 2002 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 95 streamflow-gaging stations; daily sediment records for 28 streamflow stations; 27 partial record or miscellaneous streamflow stations; stage records for 17 reservoirs; water-quality records for 17 streamflow-gaging stations, 42 ungaged streamsites, 11 lake sites, 2 lagoons, and 1 bay; and water-level records for 102 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. *Surface water, *Water quality, *Ground water, Aquifers, Chemical analysis, Gaging stations, Hydrologic data sediments, Streamflow, Water analysis, Water levels, Lakes 670 Unclassified Unclassified V CONTENTS 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 streamflow stations ...............................................................................................................xv Introduction..............................................................................................................................................................1 Cooperation..............................................................................................................................................................2 Summary of hydrologic conditions..........................................................................................................................3 Rainfall...............................................................................................................................................................3 Surface water......................................................................................................................................................3 Ground water......................................................................................................................................................5 Water quality......................................................................................................................................................8 Special networks and programs ...............................................................................................................................8 Explanation of records...........................................................................................................................................13 Station identification numbers .........................................................................................................................13 Downstream order system..........................................................................................................................13 Latitude-longitude system..........................................................................................................................13 Records of stage and water discharge..............................................................................................................19 Data collection and computation................................................................................................................19 Data presentation........................................................................................................................................20 Station manuscript................................................................................................................................21 Data table of daily mean values............................................................................................................22 Statistics of monthly mean data............................................................................................................22 Summary statistics................................................................................................................................22 Identifying estimated daily discharge.........................................................................................................24 Accuracy of the records..............................................................................................................................24 Records of surface-water quality .....................................................................................................................24 Classification of records.............................................................................................................................25 Arrangement of records..............................................................................................................................25 On-site measurements and sample collection ............................................................................................25 Water temperature......................................................................................................................................25 Sediment.....................................................................................................................................................26 Laboratory measurements ..........................................................................................................................26 Data presentation........................................................................................................................................26 Remark codes .............................................................................................................................................27 Records of ground-water levels .......................................................................................................................28 Data collection and computation................................................................................................................28 Data presentation........................................................................................................................................28 Records of ground-water quality......................................................................................................................29 Data collection and computation................................................................................................................29 Data presentation........................................................................................................................................29 Access to U.S. Geological Survey Water Data......................................................................................................30 Definition of terms.................................................................................................................................................31 Techniques of Water-Resources Investigations of the U.S. Geological Survey....................................................48 Surface- and quality-of-water records for Puerto Rico..........................................................................................53 Discharge at partial-record stations in Puerto Rico .............................................................................................481 Water-quality at partial-record stations in Puerto Rico and U.S. Virgin Islands.................................................491 Ground-water records for Puerto Rico.................................................................................................................489 Surface-water records for U.S. Virgin Islands.....................................................................................................627 Ground-water records for U.S. Virgin Islands ....................................................................................................637 Index ....................................................................................................................................................................647 VI ILLUSTRATIONS Page Figure 1. Graphs showing monthly-mean discharge of selected streams in Puerto Rico.....................................4 2. Graphs showing ground-water levels at selected wells in Puerto Rico and the U.S. Virgin Islands ....6 3. Map showing location of maximum concentrations of fecal coliform bacteria at the water-quality sampling sites in Puerto Rico....................................................................................11 4. Map showing location of maximum concentrations of fecal streptococci bacteria at the water-quality sampling sites in Puerto Rico....................................................................................12 5. Map showing location of surface-water stations in Puerto Rico.........................................................14 6. Map showing location of water-quality stations in Puerto Rico .........................................................15 7. Map showing location of ground-water stations in Puerto Rico .........................................................16 8. Map showing location of surface-water stations in the U.S. Virgin Islands .......................................17 9. Map showing location of ground-water stations in the U.S. Virgin Islands .......................................18 10. Grid showing system for numbering wells and miscellaneous sites (latitude and longitude)............19 11. Map showing the Río Guajataca basin ...............................................................................................55 12. Map showing the Río Camuy basin....................................................................................................63 13. Map showing the Río Grande de Arecibo basin.................................................................................67 14. Map showing the Río Grande de Manatí basin ................................................................................163 15. Map showing the Río Cibuco basin..................................................................................................191 16. Map showing the Río de la Plata basin.............................................................................................199 17. Map showing the Río Hondo to Río Puerto Nuevo basins...............................................................225 18. Map showing the Río Grande de Loíza basin...................................................................................257 19. Map showing northeastern river basins -- Río Herrera to Río Antón Ruíz basins...........................317 20. Map showing southeastern river basins -- Río Humacao to Quebrada Aguas Verdes basins..........355 21. Map showing south coast river basins -- Río Salinas to Río Jacaguas basins..................................373 22. Map showing south coast river basins -- Río Inabón to Río Loco basins ........................................395 23. Map showing the Río Guanajibo basin.............................................................................................445 24. Map showing the Río Yagüez and Río Grande de Añasco basins ...................................................459 25. Map showing the Río Culebrinas basin............................................................................................469 26. Map showing location of low-flow partial-record stations in Ponce, Puerto Rico..........................483 TABLES Page Table 1. Islandwide monthly rainfall for the water year 2002 and annual averages for the 30-year reference period, 1961-90......................................................................................................3 2. Highest ground-water level recorded during 2002 water year and previous highest ground-water levels at selected wells in Puerto Rico.........................................................................7 3. Lowest ground-water levels recorded during 2002 water year and previous lowest ground-water levels at selected wells in Puerto Rico.........................................................................7 4. Sediment yields in selected sediment stations for water year 2002 .......................................................9 VII SURFACE-WATER AND WATER-QUALITY STATIONS, IN DOWNSTREAM ORDER, 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 RÍO GUAJATACA BASIN Río Guajataca at Lares (d,c,b) ......................................................................................50010500 56 Lago Guajataca at Damsite near Quebradillas (e).................................................50010800 59 Canal Principal de Diversiones at Lago Guajataca (c,b)..............................................50011000 61 Río Guajataca above mouth near Quebradillas (c,b)....................................................50011400 62 RÍO CAMUY BASIN Río Camuy near Bayaney (d) .......................................................................................50014800 64 RÍO GRANDE DE ARECIBO BASIN Lago Garzas near Adjuntas (e)..............................................................................50020100 68 Río Grande de Arecibo near Adjuntas (d,c,b,s)............................................................50020500 70 Río Pellejas above Central Pellejas (d,s)......................................................................50021030 76 Río Grande de Arecibo above Utuado (d)....................................................................50021700 81 Río Viví below Hacienda El Progreso (d,s) ..........................................................50022810 87 Río Grande de Arecibo below Utuado (d,s) .................................................................50024950 92 Río Grande de Arecibo near Utuado (c,b)....................................................................50025000 97 Río Saliente at Coabey near Jauyuya (d,s) ...................................................................50025155 98 Río Jauca at Paso Palma (d,s).......................................................................................50025850 103 Río Caonillas at Paso Palma (d) ...................................................................................50026025 108 Río Caonillas above Lago Caonillas near Jayuya (c,b)................................................50026050 116 Río Caonillas below Lago Caonillas (d).......................................................................50026200 117 Río Yunes at Highway 140 near Florida (d,s)..............................................................50026400 124 Río Limón above Lago Dos Bocas (d) .........................................................................50027000 131 Lago Dos Bocas at Damsite near Utuado (e) ........................................................50027100 138 Río Grande de Arecibo below Lago Dos Bocas near Florida (d,c,b)...........................50027250 140 Río Grande de Arecibo near San Pedro (d) ..................................................................50027600 143 Río Grande de Arecibo above Arecibo (d)...................................................................50027750 148 Río Tanamá near Utuado (d,c,b,s).........................................................................50028000 150 Río Tanamá at Charco Hondo (d) ........................................................................50028400 156 Río Grande de Arecibo at Central Cambalache (d,c,b) ................................................50029000 158 RÍO GRANDE DE MANATÍ BASIN Río Orocovis at Orocovis (d) ................................................................................50030460 164 Río Orocovis near Orocovis (c,b)..........................................................................50030700 166 Río Grande de Manatí near Morovis (d,c,b).................................................................50031200 167 Lago El Guineo at Damsite near Villalba (e)........................................................50032290 173 Lago de Matrullas at Damsite near Orocovis (e)...................................................50032590 175 Río Bauta near Orocovis (d)..................................................................................50034000 177 Río Grande de Manatí at Ciales (d)..............................................................................50035000 179 Río Grande de Manatí at Highway 149 at Ciales (c,b).................................................50035500 184 Río Cialitos at Highway 649 at Ciales (c,b)..........................................................50035950 185 Río Grande de Manatí at Highway 2 near Manatí (d,c,b,p) .........................................50038100 186 LAGUNA TORTUGUERO BASIN Laguna Tortuguero Outlet near Vega Baja (c,b) ..........................................................50038200 190 VIII SURFACE-WATER AND WATER-QUALITY STATIONS, IN DOWNSTREAM ORDER, FOR WHICH RECORDS ARE PUBLISHED IN THIS VOLUME--Continued Station number Page RÍO CIBUCO BASIN Río Cibuco below Corozal (d,c,b)................................................................................50038320 192 Río Cibuco at Vega Baja (d,c,b)...................................................................................50039500 195 RÍO DE LA PLATA BASIN Lago Carite at Gate Tower near Cayey (e)...................................................................50039990 200 Río de la Plata at Proyecto La Plata (c,b).....................................................................50043000 202 Río de la Plata at Comerio (d) ......................................................................................50043800 203 Río de la Plata near Comerio (c,b)................................................................................50044000 211 Río Guadiana near Guadiana (d)...........................................................................50044810 212 Río Guadiana near Naranjito (c,b).........................................................................50044850 217 Lago La Plata at Damsite near Toa Alta (e) .................................................................50045000 218 Río de la Plata below La Plata Dam (d) .......................................................................50045010 220 Río de la Plata at Highway 2 near Toa Alta (d,c,b,s,p) ................................................50046000 222 RÍO DE BAYAMÓN BASIN Río de Bayamón at Arenas (d)......................................................................................50047535 226 Río Sabana at Vista Monte (d) ..............................................................................50047540 228 Lago de Cidra at Damsite near Cidra (e)......................................................................50047550 230 Río de Bayamón below Cidra Damsite (d)...................................................................50047560 232 Río de Bayamón near Aguas Buenas (c,b)...................................................................50047600 234 Río de Bayamón near Bayamón (d)..............................................................................50047850 235 Río Guaynabo near Bayamón (c,b) .......................................................................50047990 237 Río de Bayamón at Flood Channel at Bayamón (c,b,p) ...............................................50048510 238 RÍO PUERTO NUEVO BASIN Río Piedras: Lago Las Curías at Damsite near Río Piedras (e)..................................................50048680 240 Quebrada Las Curías below Las Curías Damsite (d) ............................................50048690 242 Río Piedras at El Señorial (d)................................................................................50048770 244 Río Piedras near Río Piedras (c,b,p)......................................................................50048800 249 Río Piedras at Hato Rey (d,c,b).............................................................................50049100 251 Laguna San José: Laguna San José No. 2 at San Juan (c,b)...............................................................50049820 254 Bahía de San Juan: Bahía de San Juan No. 5 at San Juan (c,b)............................................................50049920 255 QUEBRADA BLASINA BASIN Quebrada Blasina near Carolina (c,b)...........................................................................50050300 258 RÍO GRANDE DE LOÍZA BASIN Río Grande de Loíza at Quebrada Arenas (d) ..............................................................50050900 259 Quebrada Blanca at El Jagual (d,s)........................................................................50051150 261 Quebrada Salvatierra near San Lorenzo (d,s)........................................................50051180 263 Río Cayaguás at Cerro Gordo (d)..........................................................................50051310 265 Río Grande de Loíza at Highway 183 near San Lorenzo (d,s).....................................50051800 267 Río Turabo above Borinquen (d,s)........................................................................50053025 272 IX SURFACE-WATER AND WATER-QUALITY STATIONS, IN DOWNSTREAM ORDER, FOR WHICH RECORDS ARE PUBLISHED IN THIS VOLUME--Continued Station number Page RÍO GRANDE DE LOÍZA BASIN--Continued Río Grande de Loíza at Caguas (d,c,b,s) ......................................................................50055000 274 Río Cagüitas: Río Cagüitas near Aguas Buenas (d,s) ..................................................................50055100 281 Río Cagüitas at Villa Blanca at Caguas (d)...........................................................50055225 283 Río Cagüitas at Highway 30 at Caguas (c,b).........................................................50055250 288 Río Bairoa: Río Bairoa near Caguas (c,b).................................................................................50055400 289 Río Gurabo: Río Gurabo below El Mangó (d)...........................................................................50055750 290 Río Valenciano near Juncos (d,s).....................................................................50056400 297 Río Gurabo at Gurabo (d,s) ...................................................................................50057000 303 Río Gurabo near Gurabo (c,b)...............................................................................50057025 305 Río Cañas at Río Cañas (d,s).................................................................................50058350 306 Lago Loíza at Damsite near Trujillo Alto (c,b,e) .........................................................50059000 308 Río Grande de Loíza below Damsite (d)......................................................................50059050 311 Río Grande de Loíza below Trujillo Alto (c,b) ............................................................50059100 313 Río Canóvanas near Campo Rico (d,s).........................................................................50061800 314 RÍO ESPÍRITU SANTO BASIN Quebrada Sonadora near El Verde (d)...................................................................50063440 318 Río Espíritu Santo near Río Grande (d,c,b)..................................................................50063800 320 Río Grande near El Verde (d)................................................................................50064200 323 RÍO MAMEYES BASIN Río Mameyes near Sabana (d,s) ...................................................................................50065500 325 Río Mameyes at Mameyes (d)......................................................................................50066000 330 RÍO SABANA BASIN Río Sabana at Sabana (d)..............................................................................................50067000 332 RÍO FAJARDO BASIN Río Fajardo near Fajardo (d,c,b,p)................................................................................50071000 337 Río Fajardo below Fajardo (c,b)...................................................................................50072500 347 RÍO BLANCO BASIN Quebrada Guabá near Naguabo (d) ..............................................................................50074950 348 Río Icacos near Naguabo (d) ........................................................................................50075000 350 Río Blanco near Florida (d)..........................................................................................50076000 352 RÍO HUMACAO BASIN Río Humacao at Las Piedras (d)...................................................................................50081000 356 Río Humacao at Highway 3 at Humacao (c,b).............................................................50082000 358 RÍO GUAYANÉS BASIN Río Guayanés at Yabucoa (c,b,p) .................................................................................50083500 359 Río Guayanés above mouth at Playa de Guayanés (c,b) ..............................................50086500 361 X SURFACE-WATER AND WATER-QUALITY STATIONS, IN DOWNSTREAM ORDER, FOR WHICH RECORDS ARE PUBLISHED IN THIS VOLUME--Continued Station number Page RÍO MAUNABO BASIN Río Maunabo at Lizas (d) .............................................................................................50090500 362 Río Maunabo at Maunabo (c,b)....................................................................................50091000 364 RÍO CHICO BASIN Río Chico at Providencia (c,b)......................................................................................50091800 365 RÍO GRANDE DE PATILLAS BASIN Río Grande de Patillas near Patillas (d,c,b)..................................................................50092000 366 Río Marín near Patillas (d) ...........................................................................................50093000 369 Lago Patillas at Damsite near Patillas (e).....................................................................50093045 371 RÍO SALINAS BASIN Río Lapa near Rabo del Buey (d) .................................................................................50100200 374 Río Majada at La Plena (d)...........................................................................................50100450 376 RÍO COAMO BASIN Río Coamo at Hwy 14 at Coamo (d) ............................................................................50106100 378 Río Coamo near Coamo (c,b).......................................................................................50106500 380 RÍO DESCALABRADO BASIN Río Descalabrado near Los Llanos (d) .........................................................................50108000 381 RÍO JACAGUAS BASIN Río Toa Vaca above Lago Toa Vaca (d,s)....................................................................50110900 383 Lago Toa Vaca at Damsite near Villaba (e) ..........................................................50111210 388 Lago Guayabal at Damsite near Juana Díaz (e) ....................................................50111300 390 Río Jacaguas at Juana Díaz (d).....................................................................................50111500 392 RÍO INABÓN BASIN Río Inabón at Real Abajo (d)........................................................................................50112500 396 RÍO BUCANA BASIN Río Cerrillos above Lago Cerrillos near Ponce (d) ......................................................50113800 398 Lago Cerrillos at Damsite near Ponce (e).....................................................................50113950 400 Río Cerrillos near Ponce (d,c,b) ...................................................................................50114000 402 Río Bucaná at Highway 14 Bridge near Ponce (d).......................................................50114390 405 RÍO PORTUGUÉS BASIN Río Portugués near Tibes (d)........................................................................................50114900 407 Río Potugués near Ponce (c,b)......................................................................................50115000 415 Río Potugués at Highway 14 near Ponce (d)................................................................50115900 416 Río Portugués at Ponce (c,b,p) .....................................................................................50116200 420 RÍO GUAYANILLA BASIN Río Guayanilla near Guayanilla (d)..............................................................................50124200 422 Río Guayanilla at Central Rufina (c,b,p)......................................................................50124700 424 RÍO YAUCO BASIN Lago Lucchetti at Damsite near Yauco (e)...................................................................50125780 426 XI SURFACE-WATER AND WATER-QUALITY STATIONS, IN DOWNSTREAM ORDER, FOR WHICH RECORDS ARE PUBLISHED IN THIS VOLUME--Continued Station number Page RÍO LOCO BASIN Lago Loco at Damsite near Yauco (e)..........................................................................50128900 428 Canal de Riego de Lajas below Lago Loco Dam, Yauco (d).......................................50128905 430 Canal de Riego de Lajas above Majinas Filtration Plant (d)........................................50128920 432 Canal de Riego de Lajas below Majinas Filtration Plant (d)........................................50128925 434 Canal de Riego above Lajas Filtration Plant (d)...........................................................50128935 436 Canal de Riego de Lajas below Lajas Filtration Plant, Lajas (d) .................................50128940 438 Canal de Riego de Lajas at Barrio Palmarejo near Lajas (d)........................................50128945 440 Río Loco at Guánica (c,b,p)..........................................................................................50129700 442 RÍO GUANAJIBO BASIN Río Guanajibo at Highway 119 at San Germán (d)......................................................50131990 446 Río Guanajibo near San Germán (c,b)..........................................................................50133600 448 Río Rosario near Hormigueros (d,c,b,s)................................................................50136400 449 Río Guanajibo near Hormigueros (d,c,b,p) ..................................................................50138000 455 RÍO YAGÜEZ BASIN Río Yagüez near Mayagüez (c,b) .................................................................................50138800 460 RÍO GRANDE DE AÑASCO BASIN Lago Guayo at Damsite near Castañer (e).............................................................50141500 461 Río Grande de Añasco near Lares (c,b)........................................................................50143000 463 Río Grande de Añasco near San Sebastián (d,c,b) .......................................................50144000 464 Río Grande de Añasco near Añasco (c,b,p)..................................................................50146000 467 RÍO CULEBRINAS BASIN Río Culebrinas near San Sebastián (c,b).......................................................................50147600 470 Río Culebrinas at Highway 404 near Moca (d)............................................................50147800 471 Río Culebrinas at Margarita Dam near Aguada (d)......................................................50148890 473 Río Culebrinas near Aguada (c,b,p) .............................................................................50149100 478 Discharge at partial-record stations and miscellaneous sites low-flow partial-record stations.................................................................................................... 484 Analyses of samples collected of water-quality partial-record stations and miscellaneous sites.................................................................................................... 490 ST. THOMAS, U.S. VIRGIN ISLANDS Bonne Resolution Gut at Bonne Resolution (d) ...........................................................50252000 628 Turpentine Run at Mount Zion (d) ...............................................................................50274000 630 ST. JOHN, U.S. VIRGIN ISLANDS Guinea Gut at Bethany (d)............................................................................................50295000 632 ST. CROIX, U.S. VIRGIN ISLANDS Jolly Hill Gut at Jolly Hill (d).......................................................................................50345000 634 XII GROUND-WATER WELLS, BY BASIN, FOR WHICH RECORDS ARE PUBLISHED Page RÍO GUAJATACA BASIN Well 182422067015100 Local number 165................................................................................................................. 500 Well 182647066552400 Local number 202................................................................................................................. 501 RÍO CAMUY BASIN Well 182723066511200 Local number 1026................................................................................................................ 502 RÍO GRANDE DE ARECIBO BASIN Well 182756066454700 Local number 1051................................................................................................................ 503 Well 182616066364100 Local number 1052................................................................................................................ 504 Well 182626066345100 Local number 1053................................................................................................................ 505 Well 182603066333601 Local number 1054............................................................................................................... .506 Well 182642066394900 Local number 1055................................................................................................................. 507 Well 182209066340600 Local number 1057................................................................................................................. 508 RÍO GRANDE DE MANATÍ BASIN Well 182544066341500 Local number 205................................................................................................................. 509 Well 182757066325600 Local number 206................................................................................................................. 510 Well 182549066304300 Local number 166................................................................................................................. 511 Well 182506066280200 Local number 1076................................................................................................................ 512 Well 182308066260400 Local number 210................................................................................................................. 513 RÍO CIBUCO BASIN Well 182614066261500 Local number 1101................................................................................................................ 514 Well 182712066251700 Local number 1102................................................................................................................ 515 Well 182615066235300 Local number 211................................................................................................................. 516 Well 182647066201700 Local number 70.................................................................................................................. 517 Well 182515066194000 Local number 212................................................................................................................. 519 Well 182330066185700 Local number 213................................................................................................................. 521 Well 182426066260400 Local number 1103................................................................................................................ 522 RÍO DE LA PLATA BASIN Well 182526066165001 Local number 1127................................................................................................................ 523 Well 182548066164401 Local number 1128................................................................................................................ 524 Well 182620066163400 Local number 1129................................................................................................................ 526 Well 182620066163403 Local number 1130................................................................................................................ 527 Well 182657066162700 Local number 1131................................................................................................................ 529 Well 182657066162701 Local number 1132................................................................................................................ 530 Well 182654066150600 Local number 1133................................................................................................................ 531 Well 182530066135400 Local number 216................................................................................................................. 532 Well 182655066142400 Local number 217................................................................................................................. 533 Well 180649066095500 Local number 1134................................................................................................................ 534 XIII GROUND-WATER WELLS, BY BASIN, FOR WHICH RECORDS ARE PUBLISHED--Continued Page RÍO HONDO TO RÍO PUERTO NUEVO BASINS Well 182441066082600 Local number 219................................................................................................................. 535 Well 182531066075900 Local number 652................................................................................................................. 536 Well 182511066045401 Local number 1152................................................................................................................ 537 Well 182435066052700 Local number 1153................................................................................................................ 538 Well 182445066043401 Local number 1154................................................................................................................ 539 Well 182443066041502 Local number 1155................................................................................................................ 540 Well 182417066042700 Local number 1156................................................................................................................ 541 Well 182349066032600 Local number 1157................................................................................................................ 542 Well 182406066034700 Local number 1158................................................................................................................ 544 Well 182451066080200 Local number 1159................................................................................................................ 545 RÍO GRANDE DE LOÍZA BASIN Well 181352066025300 Local number 1176................................................................................................................ 546 Well 181311066022500 Local number 1177................................................................................................................ 547 Well 181446066013400 Local number 1178................................................................................................................ 548 Well 181539066014500 Local number 1179................................................................................................................ 549 Well 181550065593200 Local number 50.................................................................................................................. 550 Well 182515065594100 Local number 222................................................................................................................. 551 Well 181540065580300 Local number 1180................................................................................................................ 552 Well 181513065554600 Local number 1181................................................................................................................ 554 RÍO HERRERA TO RÍO ANTÓN RUIZ BASINS Well 182344065490801 Local number 1201................................................................................................................ 555 Well 182223065455900 Local number 1202................................................................................................................ 556 Well 181230065444900 Local number 1203................................................................................................................ 558 Well 182131065421100 Local number 1205................................................................................................................ 559 Well 181823065401900 Local number 1206................................................................................................................ 560 Well 181917065382701 Local number 1207................................................................................................................ 561 Well 182234065440000 Local number 1208................................................................................................................ 562 RÍO HUMACAO TO QUEBRADA AGUAS VERDES BASINS Well 180358065503600 Local number 1226................................................................................................................ 563 Well 180415065513900 Local number 96.................................................................................................................. 564 Well 175855066023100 Local number 1227................................................................................................................ 565 Well 175855066050500 Local number 1228................................................................................................................ 566 Well 175728066072200 Local number 1229................................................................................................................ 567 Well 175719066085500 Local number 1230................................................................................................................ 568 Well 175858066100200 Local number 6................................................................................................................... 570 Well 180002066132200 Local number 1231................................................................................................................ 571 Well 180001066122002 Local number 1232................................................................................................................ 572 Well 175947066130601 Local number 1233................................................................................................................ 573 Well 175957066123400 Local number 1234................................................................................................................ 574 Well 175841066104500 Local number 1238................................................................................................................ 575 Well 175814066102200 Local number 1239................................................................................................................ 576 XIV GROUND-WATER WELLS, BY BASIN, FOR WHICH RECORDS ARE PUBLISHED--Continued Page RÍO SALINAS TO RÍO JACAGUAS BASINS Well 175809066133100 Local number 1251................................................................................................................ 577 Well 180206066135500 Local number 1252................................................................................................................ 579 Well 180104066152300 Local number 1253................................................................................................................ 580 Well 175910066155500 Local number 1254................................................................................................................ 581 Well 175903066165000 Local number 1256................................................................................................................ 582 Well 175943066224800 Local number 1257................................................................................................................ 583 Well 175829066232200 Local number 87.................................................................................................................. 584 Well 180020066261500 Local number 1258................................................................................................................ 585 Well 180602066133100 Local number 1260................................................................................................................ 586 Well 175833066145800 Local number 1261................................................................................................................ 587 Well 175735066151800 Local number 1262................................................................................................................ 588 RÍO INABÓN TO RÍO LOCO BASINS Well 175950066354200 Local number 141................................................................................................................. 610 Well 175934066364800 Local number 1276................................................................................................................ 611 Well 180045066381600 Local number 1277................................................................................................................ 612 Well 180156066434000 Local number 1278................................................................................................................ 613 Well 180133066503300 Local number 132................................................................................................................. 614 RÍO GUANAJIBO BASIN Well 180132067033800 Local number 143................................................................................................................. 616 Well 180542067084000 Local number 1301................................................................................................................ 617 Well 180628067084300 Local number 1302................................................................................................................ 619 Well 180628067084301 Local number 1303................................................................................................................ 620 RÍO YAGÜEZ TO RÍO GRANDE DE AÑASCO BASINS Well 181232067083700 Local number 1326................................................................................................................ 622 RÍO CULEBRINAS BASIN Well 182017067143300 Local number 1352................................................................................................................ 624 Well 182442067091700 Local number 200................................................................................................................. 625 ST. CROIX, U.S. VIRGIN ISLANDS Well 174225064472000 Local number 2...................................................................................................................... 638 Well 174243064475100 Local number 3...................................................................................................................... 639 Well 174316064480800 Local number 13.................................................................................................................... 641 ST. THOMAS, U.S. VIRGIN ISLANDS Well 182038064550300 Local number 6...................................................................................................................... 643 Well 182038064580000 Local number 8...................................................................................................................... 644 ST. JOHN, U.S. VIRGIN ISLANDS Well 181956064464500 Local number 11.................................................................................................................... 645 XV DISCONTINUED STREAMFLOW STATIONS The following continuous-record streamflow stations in Puerto Rico and the U.S. Virgin Islands have been discontinued or converted to partial-record stations. Daily streamflow or stage records were collected for the period of record shown for each station. Station Station name Drainage Period of number area (mi2) record 50007000 Quebrada de los Cedros near Isabela 6.91 1970 50010600 Río Guajataca above Lago de Guajataca -- 1984-89 50011000 Canal Diversion Lago Guajataca -- 1970 50011200 Río Guajataca below Lago Guajataca -- 1969-70,1984-87 50011400 Río Guajataca above mouth near Quebradillas -- 1969-70,1984-89 50013000 Río Camuy near Lares 7.62 1969-71 50014000 Río Criminales near Lares 4.68 1969-70 50014600 Río Camuy at Tres Pueblos Sinkhole -- 1990-96 50015700 Río Camuy near Hatillo -- 1984-96 50016000 Río Camuy near Camuy -- 1969-73 50021050 Río Pellejas below Central Pellejas 7.89 1972-75 50021500 Río Pellejas near Utuado 9.55 1969-71 50023000 Río Viví near Central Pellejas 5.66 1969-75 50027200 Río Grande de Arecibo blw. Lago dos Bocas 169 1970-71 50031500 Río Sana Muerto near Orocovis 3.68 1965-70 50035200 Río Grande de Manatí at Hwy 145 at Ciales 132 1972 50035950 Río Cialitos at Hwy 649 at Ciales 17 1970-82 50038360 Río Mavilla near Corozal 9.51 1969-70 50038600 Río Unibón near Morovis 5.29 1969-70 50038700 Río Morovis at Morovis 1.26 1968 50038900 Río Indio at Vega Baja -- 1963,66,71 50039600 Río Cibuco at Central San Vicente -- 1969-72 50043200 Río Usabon near Barranquitas 9.15 1968-69,71 50043400 Río Aibonito Tributary near Aibonito 1.13 1968-71 50044600 Río Guadiana near Naranjito 1.73 1971 50044650 Quebrada del Toro near Naranjito 0.54 1971 50044800 Quebrada Anones near Naranjito 2.32 1971 50045700 Río Lajas at Toa Alta 8.65 1966-75 50047820 Río de Bayamón at Hwy 174 near Bayamón 31.90 1966 50048000 Río de Bayamón at Bayamón 71.90 1963-67 50049000 Río Piedras at Río Piedras 12.5 1971-82, 1987-93 50049310 Quebrada Josefina at Piñero Avenue 3.84 1988-91 50053050 Río Turabo at Borinquen 7.89 1984-90 50054000 Quebrada de las Quebradillas near Caguas 6.25 1969-71,73 50055170 Río Cagüitas near Caguas 8.27 1992-97 50055390 Río Bairoa at Bairoa 5.08 1990-2001 50055650 Quebrada Caimito near Juncos 0.82 1984-87 50056000 Río Valenciano near Las Piedras 6.85 1971 50056900 Quebrada Mamey near Gurabo 2.30 1984-92 50058300 Quebrada Arena near Caguas -- 1971 XVI DISCONTINUED STREAMFLOW STATIONS--Continued Station Station name Drainage Period of number area (mi2) record 50061300 Río Canovanillas near Loíza 14.40 1968-73 50062500 Río Herrera near Colonia Dolores 2.75 1968-72 50063300 Río Espíritu Santo near El Verde 2.23 1968-73 50063500 Quebrada Toronja at El Verde 0.064 1983-96 50065700 Río Mameyes at Hwy 191 at Mameyes 11.80 1967-85 50070500 Río Fajardo above Fajardo 3.69 1995-2001 50072000 Río Fajardo at Fajardo 21.60 1960-63 50073200 Río Daguao at Daguao 2.26 1966-82 50073400 Quebrada Palma at Daguao 4.84 1972-77 50074000 Río Santiago at Naguabo 4.99 1966-82 50075500 Río Blanco at Florida 11.00 1966-82 50077000 Río Blanco at Río Blanco 17.60 1973-77 50077400 Río Blanco at Colonia La Fe 18.80 1967-70 50078500 Río Anton Ruíz at Central Pasto Viejo 4.33 1968 50081500 Río Humacao near Humacao 9.23 1973 50082000 Río Humacao at Hwy 3 at Humacao 17.30 1983-85 50082200 Río Humacao near La Suiza 19.90 1965-66, 1969-71 50082800 Río Guayanés near Colonia Laura 4.69 1969-82 50083500 Río Guayanés near Yabucoa 17.20 1969-71 50084000 Río Limones near Yabucoa 7.89 1969-71 50085100 Río Guayanés at Central Roig 26.60 1965-66, 1968,70 50086100 Río del Ingenio at Comunas 5.50 1965-66, 1968-69 50086500 Río Guayanés at Playa Guayanés 34.00 1965-66, 1968-71 50087200 Caño Santiago near Central Roig 6.04 1965-71 50091000 Río Maunabo at Maunabo 12.40 1965,67, 1969-82 50091200 Río Maunabo near Maunabo 12.70 1971-72 50091400 Río Jacaboa near Lamboglia 4.13 1965-73 50091700 Río Chico at Patillas 6.82 1965, 1969-72 50091800 Río Chico at Providencia 4.90 1965, 1967-69, 1971 50094200 Río Grande de Patillas at Patillas 27.90 1967, 1969, 1971 50094300 Río Grande de Patillas at Providencia 29.00 1971 50094400 Río Nigua at Pitahaya 5.86 1965, 1969, 1970-71, 1973 50095200 Río Guamaní at Guayama 8.22 1969-71 50095500 Río Guamaní near Guayama 12.30 1969-70 50099000 Quebrada Aguas Verdes near Salinas 0.39 1989 50106500 Río Coamo near Coamo 46.00 1967-68, 1984-85, 1986 50106900 Río Coamo below Lago Coamo near Coamo 65.40 1967-68 50107200 Río Coamo at mouth near Santa Isabel 69.30 1967-68 50108200 Río Descalabrado at Las Ollas 13.90 1965, 1967-71 50108500 Río Descalabrado near Santa Isabel 18.10 1966-67 XVII DISCONTINUED STREAMFLOW STATIONS--Continued Station Station name Drainage Period of number area (mi2) record 50111200 Río Toa Vaca near Villalba 21.40 1966-70 50111700 Río Jacaguas near Juana Díaz 53.20 1966-68 50111750 Río Jacaguas below Quebrada Guanábana 56.30 1989 50112100 Río Jacaguas near Arús 59.60 1966-67 50112600 Río Inabón at Coto Laurel -- 1967-71 50113100 Río Guayo near Coto Laurel 11.80 1965, 1968-71 50113500 Río Inabón near Arús 30.20 1964-65 50114400 Río Bucaná near Ponce 25.60 1965-81 50114700 Río Bucaná near Playa de Ponce 28.40 1964-67 50115000 Río Portugués near Ponce 8.82 1964-97 50116500 Río Portugués at Highway 2 Bypass at Ponce 20.50 1964-65 50119000 Río Matilde at Ponce 19.40 1965-66 50121000 Río Tallaboa at Peñuelas 24.20 1959-82 50122000 Río Tallaboa at Tallaboa 31.50 1959-63 50124000 Río Guayanilla nr Guayanilla 18.50 1961-69 50124500 Río Guayanilla at Guayanilla 20.80 1971-82 50125900 Río Duey above Diversion near Yauco 8.93 1977-80 50126150 Río Yauco above Diversion Monserrate near Yauco 27.20 1978-85 50128000 Río Yauco near Yauco 45.50 1962-64, 1977-85 50129000 Río Loco near Yauco 8.50 1963-67 50129500 Río Loco near Guánica 21.00 1963-69 50129900 Laguna Cartagena near Boquerón -- 1984-86 50130320 Quebrada Mamey at Joyuda 0.38 1986-88 50136000 Río Rosario at Rosario 16.40 1975-86 50141000 Río Yahuecas near Adjuntas 15.40 1980-85 50145000 Río Grande de Añasco at El Espino 108.00 1959-66, 1961-63 50147000 Río Culebrinas at San Sebastian 16.70 1960-82 50214500 Quebrada Resaca near Monte Resaca, Culebra 0.23 1991-93 50215000 Drainage Canal at Culebra Airport, Culebra 0.08 1991-93 50231000 Quebrada Confresí Tributary near Isabel II, Vieques 0.28 1991-93 50232000 Quebrada La Mina near Esperanza, Vieques 0.68 1991-96 50233000 Quebrada Pilón at Colonia Puerto Real, Vieques 0.67 1991-96 50276000 Turpentine Run at Mariendal, St.Thomas 2.97 1963-69, 1978-86 50292600 Lameshur Bay Gut at Lameshur, St. John 0.38 1992-94 50294000 Fish Bay Gut at Fish Bay, St. John 1.48 1992-94 50295500 Cruz Bay Gut at Cruz Bay, St. John, VI 0.09 1992-93 50332000 River Gut at River 1.42 1991-93 50333500 River Gut near Golden Grove 5.40 1990-93 50333700 River Gut at Hwy 66 at Fairplanes 5.89 1990-96 50334500 Bethehem Gut at Hwy 66 at Fairplanes 4.11 1990-96 50337500 Gut 4.5 at Cane Valley 0.2 1991-93 50348000 Salt River at Canaan 0.36 1991-93 50349000 Gut 10 near Altona 0.13 1991-93 XVIII THIS PAGE IS INTENTIONALLY BLANK 1 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 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 U.S. Geological Survey, the data are published annually in this report series entitled "Water Resources Data for Puerto Rico and the U.S. Virgin Islands, 2002." This report includes records on both surface and ground water. Specifically, it contains: (1) discharge records for 95 streamflow gaging stations, daily sediment records for 28 streamflow stations, 27 partial-record or miscellaneous streamflow stations, stage records for 17 reservoirs, and (2) water-quality records for 17 streamflow-gaging stations, and for 42 ungaged stream sites, 11 lake sites, 2 lagoons, and 1 bay, and (3) water-level records for 102 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 to 2001 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 U.S. Geological Survey for all States. These official Survey reports have an identification number consisting of the two-letter State abbreviation, the last two digits of the water year, and the volume number. For example, this volume is identified as "U.S. Geological Survey Water- Data Report PR-02-1." 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. 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 (787) 749-4346. 2 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 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 U.S. Geological 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 Highway Authority Puerto Rico Department of Natural and Environmental Resources Puerto Rico Department of Health Puerto Rico Electric Power Authority Puerto Rico Solid Waste Management Authority Puerto Rico Legislature Puerto Rico Emergency Management Agency U.S. Virgin Islands Department of Planning and Natural Resources Puerto Rico Infrastructure Financing Authority Funds were also provided by the U.S. Army, Corps of Engineers, for the collection of records at six gaging stations published in this report. 3 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 SUMMARY OF HYDROLOGIC CONDITIONS Rainfall During water year 2002 (October 2001 to September 2002), total rainfall throughout Puerto Rico was slightly above normal. Rainfall above normal was registered during November, December, April, and June. During these months, rainfall was between 9 to 135 percent above normal. These above normal rainfall conditions were produced mainly by tropical waves and cold fronts which passed through the island. The most significant rainfall event was produced by a cold front which affected the island during early November. This cold front produced heavy rain mainly over the northern, central, and eastern regions of the island during November 7-9, 2001. In spite of the excessive rainfall resulted from these rain-producing weather systems, monthly rainfall was below normal values during most of the water year 2002. Monthly rainfall below normal values ranged from 3 to 49 percent. Normal rainfall is defined as the mean monthly rainfall for certain period of time. In Puerto Rico, the reference period used to define the monthly normal rainfall is 1971-2000 (table 1). In the U.S. Virgin Islands, annual rainfall was deficient, with an average of 89 percent of normal. During eight months of water year 2002, rainfall was below normal with averages that ranged from 2 to 75 percent below normal. Only during October, December, March, and April rainfall was above normal ranging from 1 to 145 above normal. Table 1. Islandwide monthly rainfall for the water year 2002 and monthly normal rainfall for the 30-year reference period, 1971-2000. Data from the National Oceanographic and Atmospheric Administration ____________________________________________________ 2002 Water Year 30-year normal Month (inches) (inches) ____________________________________________________ October 6.03 7.98 November 8.20 6.53 December 7.57 4.05 January 2.60 3.20 February 1.49 2.90 March 2.86 2.96 April 9.84 4.19 May 4.72 6.67 June 4.85 4.46 July 3.46 4.88 August 5.86 6.51 September 6.33 7.91 TOTAL 63.81 62.24 ____________________________________________________ Surface Water Streamflow in Puerto Rico during water year 2002 was within normal, as recorded by the four index stations compared with the long-term median of the monthly mean flows. Tropical disturbances and cold fronts passing through the area produced excessive rainfall that caused riverine flooding throughout the island. A cold front that passed through the island during November 7-9 produced heavy rain that caused extensive flooding mainly at the northern, central, and eastern areas of the island. This flood event produced the annual peak flows at most of the streamflow gaging stations throughout Puerto Rico. Comparisons of the monthly mean flows during water year 2002 with the long-term minimum, median, and maximum of the monthly mean flows, for the period of record at the index stations on the Río Grande de Manatí (northern area), the Río Fajardo (eastern area), the Río Inabón (southern area), and the Río Grande de Añasco (western area) are shown in figure 1. The following overview of the four areas, describes in more detail, the hydrologic conditions prevailing in Puerto Rico for the 2002 water year. 4 1 10 100 1,000 10,000 1 10 100 1,000 1 10 100 1,000 1 10 100 1,000 10,000 Unshaded area indicates range between highest and lowest monthly-mean discharges for the period of record to water year 2002. O N D J F M M A A J J S 2002 2001 O N D J F M M A A J J S 2002 2001 O N D J F M M A A J J S 2002 2001 O N D J F M M A A J J S 2002 2001 RÍO GRANDE DE AÑASCO NEAR SAN SEBASTIÁN WEST (50144000) RÍO GRANDE DE MANATÍ AT HWY 2 NORTH (50038100) RÍO INABÓN AT REAL ABAJO SOUTH (50112500) RÍO FAJARDO NEAR FAJARDO EAST (50071000) MONTHLY-MEAN DISCHARGE, IN CUBIC FEET PER SECOND MONTHLY-MEAN DISCHARGE, IN CUBIC FEET PER SECOND 2002 MONTHLY MEAN 1964-02 MEDIAN OF MONTHLY MEAN 2002 MONTHLY MEAN 1961-02 MEDIAN OF MONTHLY MEAN 2002 MONTHLY MEAN 1965-02 MEDIAN OF MONTHLY MEAN 2002 MONTHLY MEAN 1962-02 MEDIAN OF MONTHLY MEAN Figure 1. Monthly-mean discharge of selected streams in Puerto Rico. 5 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 In the northern area, represented by the Río Grande de Manatí index station, monthly mean flows were below the long-term median of the monthly mean flows during six months and well above the long-term median of the monthly mean flows during the other six months. The monthly mean flows for October, January, February, March, July, and August fluctuated between 11 to 71 percent below the long-term median of the monthly mean flows. During October, the four index stations registered monthly mean flows that ranged from 14 to 71 percent below the long-term median of the monthly mean flows. Historical minimum monthly mean flow was recorded during October at the Río Grande de Manatí index station. At the northern area, above normal monthly mean flows were recorded during November, December, April, May, June, and September. The monthly mean flows for these months ranged from 1 to 511 percent above the long-term median of the monthly mean flows. A historical maximum monthly mean flow was set for November at the Río Grande de Manatí index station. In general, the streamflow conditions at the eastern area were very similar to the streamflow conditions at the northern area. As shown by the Río Fajardo near Fajardo index station in figure 1, during six months the monthly mean flows were below the long-term median of the monthly mean flows, while the other six months the monthly mean flows were above the long-term median of the monthly mean flows. The monthly mean flows ranged from 25 to 52 percent below the long-term median and from 3 to 162 percent above the long-term median of the monthly mean flows. The monthly mean flows registered at the Río Inabón at Real Abajo index station were near the long-term median of the monthly mean flows during the first six months of water year 2002. A significant increase in streamflow was observed at this index station during April, when the monthly mean flow was above the long-term median of the monthly mean flows by 169 percent. The monthly mean flows for the rest of the water year was, in general, below the long-term median of the monthly mean flows. The western area was the wettest of this water year, as shown by the index station at Río Grande de Añasco (figure 1). Monthly mean flows were above the long-term median of the monthly mean flows during November, December, January, February, March, April, and May ranging from 33 to 729 percent. A historical maximum monthly mean flow for April was set at the Río Grande de Añasco index station. Monthly mean flows ranging from 11 to 29 percent below the long-term median of the monthly mean flows were observed during the last four months of the water year. In the U.S. Virgin Islands, the monthly mean flows were below the long-term median of the monthly mean flows during most of the water year 2002. Streamflow records from the U.S. Virgin Islands network of stations shown that monthly mean flows during December were above the long-term median of the monthly mean flows. Ground Water In general, the water-levels trends and fluctuations during the water year 2002 followed a seasonal pattern, resulting from a slightly above normal rainfall accumulation combined with continuous and mostly moderate ground- water withdrawals (fig. 2). The net seasonal change in water level reported as feet below land surface for all the index wells in figure 2 during water year 2002 is near or slightly above zero. This is an indication that, in general, there was no significant net change in storage in the limestone and alluvial aquifers of Puerto Rico, and the fractured-rock volcanic aquifers in St. John, U.S. Virgin Islands, during the year 2002. The highest water level recorded during the year 2002 was slightly above the historic high at three of the ground- water monitoring stations (table 2). The highest water-level recorded in the remaining ground-water monitoring stations during the year 2002 was slightly below the historic high. In areas where ground-water withdrawals constitute an important resource for drinking water purposes, the lowest water level recorded was below the historic low in 6 of the ground-water monitoring stations (table 3). During most of water year 2002, rainfall ranged from 3 to 49 percent below the normal range except for the months of November, December, April, and June. For water year 2002, rainfall distribution in Puerto Rico climatic subdivisions at which the principal aquifer systems are found was as follow: North coast limestone, 108 percent of normal; South coastal plain, 87 percent of normal; Eastern alluvial valleys, 106 percent of normal; Western alluvial valleys, 108 percent of normal. For water year 2002, rainfall distribution in the U.S. Virgin Islands climatic subdivisions at which the principal aquifers are found was about 89 percent of normal. 6 24 25 26 27 28 29 30 37 38 39 40 41 42 43 44 45 46 Nov Dec 2002 MONTH WATER LEVEL, IN FEET BELOW LAND-SURFACE DATUM 2001 Jan Feb Mar Apr May June July Aug Sep 0 5 10 15 20 WELL 70, SABANA HOYOS 2 WELL, PUERTO RICO WELL 87, ALOMAR 1 WELL, PUERTO RICO WELL 11, GUINEA GUT, ST JOHN, U.S. VIRGIN ISLANDS Oct Figure 2. Ground-water levels at selected wells in Puerto Rico and the U.S. Virgin Islands. 7 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 Table 2. Highest ground-water levels recorded during 2002 water year and previous highest ground-water levels at selected wells in Puerto Rico. [PR, Puerto Rico; +, water level above land-surface datum; ft-blsd, feet below land-surface datum; mm-dd-yy, month-day-year; mm-yy, month-year] ______________________________________________________________________________________________________________________ 2002 Previous highest highest water water Period of Well Local level Date level Date record name number Location (ft-blsd) (mm-dd-yy) (ft-blsd) (mm-dd-yy) (mm-yy) ______________________________________________________________________________________________________________________ Saltos 1 165 PR 35.17 06-06-02 38.24 10-16-98 01-82 to 09-02 PRASA Florida 1 1057 PR 137.07 11-08-01 137.91 09-22-98 08-96 to 09-02 Piezometer 1129 PR 33.83 11-17-01 35.29 01-15-99 02-00 to 09-02 Higuillar USGS 1 Piezometer 217 PR +0.08 11-09-01 0.02 05-16-86 11-85 to 09-02 Monserrate 2 Piezometer 652 PR 3.10 09-24-02 4.59 05-28-00 05-97 to 09-02 USGS Bldg. 652 Piezometer 1159 PR 25.54 09-15-02 27.56 09-29-01 09-97 to 09-02 Fort Buchanan 1 09-30-01 Piezometer 1180 PR 10.65 05-09-02 10.71 01-21-00 08-95 to 09-02 Caguas-Juncos 18 Piezometer 1208 PR +3.02 09-18-02 +1.60 09-21-98 06-97 to 06-02 Qda. Mata de 09-22-98 Plátanos 1 Piezometer 1226 PR +2.44 01-07-02 +0.29 11-17-99 09-97 to 09-02 Yabucoa USGS 01-08-02 Brackish Yabucoa 7 96 PR 6.74 06-07-02 8.75 10-31-99 04-78 to 09-02 Piezometer 1303 PR 4.42 05-10-02 4.88 09-28-01 05-96 to 09-02 Cabo Rojo ______________________________________________________________________________________________________________________ Table 3. Lowest ground-water levels recorded during 2002 water year and previous lowest ground-water levels at selected wells in Puerto Rico. [PR, Puerto Rico; ft-blsd, feet below land-surface datum; mm-dd-yy, month-day-year; mm-yy, month-year] ______________________________________________________________________________________________________________________ 2002 Previous lowest lowest water water Period of Well Local level Date level Date record name number Location (ft-blsd) (mm-dd-yy) (ft-blsd) (mm-dd-yy) (mm-yy) ______________________________________________________________________________________________________________________ NC-5 Cruce 205 PR 96.61 08-27-02 92.21 08-06-01 12-86 to 09-02 Dávila Piezometer Río Mameyes 2 1202 PR 14.63 09-11-02 14.52 08-22-00 09-97 to 09-02 08-23-00 Piezometer 1207 PR 13.74 04-15-02 12.40 08-17-99 08-95 to 09-02 USGS RF 12 08-18-99 PRASA Villodas 1238 PR 38.67 09-15-02 32.96 07-22-98 03-98 to 09-02 Jobos Well 1239 PR 32.63 09-30-02 31.42 08-06-98 04-97 to 09-02 Bauzá 1 1260 PR 219.21 08-26-02 215.70 06-08-98 10-97 to 09-02 Rincón 4 1352 PR 36.71 08-05-02 35.62 06-12-00 05-96 to 09-02 to 06-15-00 ______________________________________________________________________________________________________________________ 8 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 The period of record of many of the ground-water monitoring sites dates back to 1997, when the ground-water monitoring network was established. Fluctuations in water levels observed at these monitoring sites during water year 2002 were of the same order of magnitude as the historic ground-water levels at the index stations obtained since the 1960's. Figures 7 and 9 show the locations of the ground-water stations maintained by the USGS in Puerto Rico and the U.S. Virgin Islands. Water Quality The U.S. Geological Survey, in cooperation with several Commonwealth agencies, collected water-quality data at 74 surface-water stations during water year 2002. Water-quality data collected at these stations included major ions, trace elements, nutrients, pesticides, as well as fecal indicator bacteria and physical parameters. The presence of high concentrations of fecal coliform (fig. 3) and fecal streptococcal (fig. 4) bacteria during water year 2002 continued to be one of the principal water-quality problems in Puerto Rico. The Río de Bayamón and the Río Grande de Loíza basins have the higher fecal coliform and fecal streptococci bacteria concentrations. Cities with high population are located within these basins. Although water pollution control measures are being implemented to decrease the concentrations of these bacteria, the values are still above the established water-quality standards for natural waters. Areas drained by major rivers where there is intense land use (agriculture, industry, urbanization) have, in general, fairly high concentrations of fecal indicator bacteria. These include the municipios of Aguadilla, Añasco, Arecibo, Humacao, and Manatí. The ability of communities to treat drinking water for bacteria is often inhibited by runoff with high suspended-sediment concentration and the associated turbidity problems. This is generally the principal cause in streams which suffer from intense resource utilization (agriculture and urban development) where soil movement is involved. The U.S. Geological Survey, in cooperation with various Commonwealth and Federal agencies, collected suspended-sediment samples at 28 stations in Puerto Rico during the 2002 water year. High suspended-sediment concentrations are a common problem in many streams in Puerto Rico. Most of the streams with high suspended- sediment concentrations are related to land use, especially urban development, agriculture, and activities which disturb soil cover. High suspended-sediment concentrations affect the operation of public surface-water supply filtration plants and contribute with the storage depletion capacities of reservoirs. Table 4 summarizes the annual sediment discharge (in tons) and sediment yield (in tons/mi²), for some of the monitored stations. Calculated sediment yields varied from a minimum of 390 tons/mi² at station 50114900, Río Portugués at Tibes, to a maximum of 7,690 tons/mi² at station 50048770, Río Piedras at El Señorial. The average sediment yield was 2,140 tons/mi² and the median was 1,310 tons/mi². 9 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 Table 4. Sediment yields in selected sediment stations for water year 2002. [mi², square miles; tons/mi², tons per square miles] Station number Station name Drainage area, in mi² Annual sediment discharge, in tons Sediment yields, in tons/mi² 50020500 Río Grande de Arecibo near Adjuntas 12.7 24,200 1,910 50021030 Río Pellejas above Central Pellejas 6.83 4,590 672 50021700 Río Grande de Arecibo Above Utuado 36.0 28,300 786 50022810 Río Viví below Hacienda El Progreso 2.99 5,980 2,000 50024950 Río Grande de Arecibo below Utuado 65.6 169,000 2,580 50025155 Río Saliente at Coabey near Jayuya 9.25 6,250 675 50025850 Río Jauca at Paso Palma 6.89 2,750 399 50026025 Río Caonillas at Paso Palma 37.9 61,200 1,610 50026400 Río Yunes at Hwy 140 near Florida 13.9 49,500 3,560 50027000 Río Limón above Lago Dos Bocas 33.2 92,300 2,780 50028000 Río Tanamá near Utuado 18.4 116,000 6,300 50031200 Río Grande de Manatí near Morovis 55.2 107,000 1,940 50043800 Río de la Plata at Comerío 109 140,000 1,290 50048770 Río Piedras at El Señorial 7.49 57,600 7,690 50051800 Río Grande de Loíza at Hwy 183 near San Lorenzo 25.0 32,000 1,280 50055000 Río Grande de Loíza at Caguas 89.8 78,900 879 50055750 Río Gurabo below El Mangó 22.3 19,400 870 50056400 Río Valenciano near Juncos 16.4 102,000 6,220 50065500 Río Mameyes near Sabana 6.88 4,160 605 50071000 Río Fajardo near Fajardo 14.9 19,900 1,340 50110900 Río Toa Vaca above Lago Toa Vaca 14.2 13,800 972 50114900 Río Portugués near Tibes 7.27 2,840 390 50136400 Río Rosario near Hormigueros 18.3 14,400 787 50148890 Río Culebrinas at Margarita Dam near Aguada 94.6 369,000 3,900 10 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 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) Program 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, diverse, 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. 11 Figure 3. Location of maximum concentrations of fecal coliform bacteria at the water-quality sampling sites in Puerto Rico. 12 Figure 4. Location of maximum concentrations of fecal streptococci bacteria at the water-quality sampling sites in Puerto Rico. 13 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 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 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 2002 water year that began October 1, 2001 and ended September 30, 2002. 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 9. The following sections of the introductory text are presented to provide users with a more detailed explanation of how the hydrologic data published in this report were collected, analyzed, computed, and arranged for presentation. Station Identification Numbers Each data station, whether stream site 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. 10). 14 Figure 5. Location of surface-water stations in Puerto Rico. 15 Figure 6. Location of water-quality stations in Puerto Rico. 16 Figure 7. Location of ground-water stations in Puerto Rico. 17 Figure 8. Location of surface-water stations in the U.S. Virgin Islands. 18 Figure 9. Location of ground-water stations in the U.S. Virgin Islands. 19 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 Figure 10. 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. 134 132 131 27 74 16 COORDINATES FOR WELLS 27 (180150066474900) AND 74 (180135066471000) COORDINATES FOR WELLS 132 (180133066503300) AND 134 (180120066503200) COORDINATES FOR WELLS 131 (180058066502700) COORDINATES FOR WELLS 16 (175922066495800) 20 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 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. 21 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 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. DRAINAGE AREA.--Drainage areas are measured using the most accurate maps available. Drainage areas are updated as better maps become available. PERIOD OF RECORD.--This indicates the period for which there are published records for the station or for an equivalent station. An equivalent station is one that was in operation at a time that the present station was not, and whose location was such that records from it can reasonable be considered equivalent with records from the present station. REVISED RECORDS.--Because of new information, published records occasionally are found to be incorrect, and revisions are printed in later reports. Listed under this heading are all the reports in which revisions have been published for the station and the water years to which the revisions apply. If a revision did not include daily, monthly, or annual figures of discharge, that fact is noted after the year dates as follows: "(M)" means that only the instantaneous maximum discharge was revised; "(m)" that only the instantaneous minimum was revised; and "(P)" that only peak discharges were revised. If the drainage area has been revised, the report in which the most recently revised figure was first published is given. GAGE.--The type of gage in current use, the datum of the current gage, and a condensed history of the types, locations, and datums of previous gages are given under this heading. REMARKS.--All periods of estimated daily-discharge record will either be identified by date in this paragraph of the station description for water-discharge stations or flagged in the daily-discharge table. (See next section, "Identifying Estimated Daily Discharge.") If a remarks statement is used to identify estimated record, the paragraph will begin with this information presented as the first entry. The paragraph is also used to present information relative to the accuracy of the records, to special methods of computations, to conditions that affect natural flow at the station and, possibly, to other pertinent items. For reservoir stations, information is given on the dam forming the reservoir, the capacity, outlet works and spillway, and purpose and use of the reservoir. COOPERATION.--Records provided by a cooperating organization or obtained for the Geological Survey by a cooperating organization are identified here. EXTREMES OUTSIDE PERIOD OF RECORD.--Included here is information concerning major floods or unusually low flows that occurred outside the stated period of record. The information may or may not have been obtained by the U.S. Geological Survey. REVISIONS.--If a critical error in published records is discovered, a revision is included in the first report published following discovery of the error. 22 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 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 Values 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. 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. 23 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 The following summary statistics data, as appropriate, are provided with each continuous record of discharge. Comments to follow clarify information presented under the various line headings of the summary statistics table. ANNUAL TOTAL.--The sum of the daily mean values of discharge for the year. At some stations the annual total discharge is adjusted for reservoir storage or diversion. The adjusted figures are identified by a symbol and corresponding footnotes. ANNUAL MEAN.--The arithmetic mean of the individual daily mean discharges for the year noted or for the designated period. At some stations the yearly mean discharge is adjusted for reservoir storage or diversion. The adjusted figures are identified by a symbol and corresponding footnotes. HIGHEST ANNUAL MEAN.--The maximum annual mean discharge occurring for the designated period. LOWEST ANNUAL MEAN.--The minimum annual mean discharge occurring for the designated period. HIGHEST DAILY MEAN.--The maximum daily mean discharge for the year or for the designated period. LOWEST DAILY MEAN.--The minimum daily mean discharge for the year or for the designated period. ANNUAL 7-DAY MINIMUM.--The lowest mean discharge for 7 consecutive days for a calendar year or a water year. Note that most low-flow frequency analyses of annual 7-day minimum flows use a climatic year (April 1 - March 31). The date shown in the summary statistics table is the initial date of the 7-day period. (This value should not be confused with the 7-day 10-year low-flow statistics). MAXIMUM 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.) MAXIMUM 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 given time period were uniformly distributed on it. 10 PERCENT EXCEEDS.--The discharge that is exceeded 10 percent of the time for the designated period. 50 PERCENT EXCEEDS.--The discharge that is exceeded 50 percent of the time for the designated period. 90 PERCENT EXCEEDS.--The discharge that is exceeded 90 percent of the time for the designated period. 24 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 Data collected at partial-record stations follow the information for continuous-record sites. Data for partial-record discharge stations are presented in a table of discharge measurements at low-flow partial-record stations. These measurements are generally made in times of drought to give better areal coverage to those events. Those measurements and others collected for some special reason are called measurements at miscellaneous sites. Identifying Estimated Daily Discharge Estimated daily-discharge values published in the water-discharge tables are identified by flagging individual daily values with the letter symbol "e" and printing a table footnote, "e Estimated." Accuracy of the Records The accuracy of streamflow records depends primarily on: (1) The stability of the stage-discharge relation or, if the control is unstable, the frequency of discharge measurements; and (2) the accuracy of measurements of stage, measurements of discharge, and interpretation of records. The accuracy attributed to the records is indicated under "REMARKS." "Excellent" means that about 95 percent of the daily discharges are within 5 percent of the true; "good," within 10 percent; and "fair," within 15 percent. Records that do not meet the criteria mentioned, are rated "poor." Different accuracies may be attributed to different parts of a given record. Daily mean discharges in this report are given to the nearest hundredth of a cubic foot per second for values less than 1 ft3/s; to the nearest tenth between 1.0 and 10 ft3/s; to whole numbers between 10 and 1,000 ft3/s; and to 3 significant figures for more than 1,000 ft3/s. The number of significant figures used is based solely on the magnitude of the discharge value. The same rounding rules apply to discharges listed for partial-record stations and miscellaneous sites. 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. 25 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 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. A1, 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. 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. 26 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 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. C1. Methods used by the Geological Survey laboratories are given in TWRI, Book 1, Chap. D2; Book 3, Chap. C2; Book 5, Chap. A1, A3, and A4. Data Presentation For continuing-record stations, information pertinent to the history of station operation is provided in descriptive headings preceding the tabular data. These descriptive headings give details regarding location, drainage area, period of record, type of data available, instrumentation, general remarks, cooperation, and extremes for parameters currently measured daily. Tables of chemical, physical, biological, radiochemical data, and so forth, obtained at a frequency less than daily are presented first, and tables of "daily values" of specific conductance, pH, water temperature, dissolved oxygen, and suspended sediment then follow in sequence, when these parameters are studied. In the descriptive headings, if the location is identical to that of the discharge gaging station, neither the LOCATION nor the DRAINAGE AREA statements are repeated. The following information, as appropriate, is provided with each continuous-record station. Comments that follow clarify information presented under the various headings of the station description. LOCATION.--See Data Presentation under "Records of Stage and Water Discharge;" same comments apply. DRAINAGE AREA.--See Data Presentation under "Records of Stage and Water Discharge;" same comments apply. PERIOD OF RECORD.--This indicates the periods for which there are published water-quality records for the station. The periods are shown separately for records of parameters measured daily or continuously and those measured less than daily. For those measured daily or continuously, periods of record are given for the parameters individually. 27 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 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. 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 M Presence verified, not quantified 28 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 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 easy reference. 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 (lsd). 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. 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 geological 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 measurement 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. 29 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 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. 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. 30 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 ACCESS TO U.S. GEOLOGICAL SURVEY WATER DATA The U.S. Geological Survey provides near real-time stage and discharge data for many of the gaging stations equipped with the necessary telemetry and historic daily-mean and peak-flow discharge data for most current or discontinued gaging stations through the world wide web (WWW). These data may be accessed at http://water.usgs.gov Some water-quality and ground-water data also are available through the WWW. In addition, data can be provided in various machine-readable formats on magnetic tape or 3-1/2 inch floppy disk. 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 District Offices (see address on the back of the title page). 31 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 DEFINITION OF TERMS Specialized technical terms related to streamflow, water-quality, and other hydrologic data, as used in this report, are defined below. Definitions of common terms such as algae, water level, and precipitation are given in standard dictionaries. Not all terms defined in this alphabetical list apply to every State. See also table for converting inch/pound units to International System (SI) units on the inside of the back cover. Acid neutralizing capacity (ANC) is the equivalent sum of all bases or base-producing materials, solutes plus particulates, in an aqueous system that can be titrated with acid to an equivalence point. This term designates titration of an “unfiltered” sample (formerly reported as alkalinity). Acre-foot (AC-FT, acre-ft) is a unit of volume, commonly used to measure quantities of water used or stored, equivalent to the volume of water required to cover 1 acre to a depth of 1 foot and equivalent to 43,560 cubic feet, 325,851 gallons, or 1,233 cubic meters. (See also “Annual runoff”) Adenosine triphosphate (ATP) is an organic, phosphate-rich compound important in the transfer of energy in organisms. Its central role in living cells makes ATP an excellent indicator of the presence of living material in water. A measurement of ATP therefore provides a sensitive and rapid estimate of biomass. ATP is reported in micrograms per liter. Algal 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 at stationary phase and is expressed as milligrams dry weight of algae produced per liter of sample. (See also “Biomass” and “Dry weight”) Alkalinity is the capacity of solutes in an aqueous system to neutralize acid. This term designates titration of a “filtered” sample. Annual runoff is the total quantity of water that is discharged (“runs off”) from a drainage basin in a year. Data reports may present annual runoff data as volumes in acre-feet, as discharges per unit of drainage area in cubic feet per second per square mile, or as depths of water on the drainage basin in inches. Annual 7-day minimum is the lowest mean value for any 7-consecutive-day period in a year. Annual 7-day minimum values are reported herein for the calendar year and the water year (October 1 through September 30). Most low-flow frequency analyses use a climatic year (April 1-March 31), which tends to prevent the low-flow period from being artificially split between adjacent years. 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.) Aroclor is the registered trademark for a group of poly-chlorinated biphenyls that were manufactured by the Monsanto Company prior to 1976. Aroclors are assigned specific 4-digit reference numbers dependent upon molecular type and degree of substitution of the biphenyl ring hydrogen atoms by chlorine atoms. The first two digits of a numbered aroclor represent the molecular type, and the last two digits represent the percentage weight of the hydrogen-substituted chlorine. Artificial substrate is a device that 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 collected. 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 collection. (See also “Substrate”) 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. Ash mass of zooplankton and phytoplankton is expressed in grams per cubic meter (g/m3), and periphyton and benthic organisms in grams per square meter (g/ m2). (See also “Biomass” and “Dry mass”) Aspect is the direction toward which a slope faces with respect to the compass. 32 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 Bacteria are microscopic unicellular organisms, typically spherical, rodlike, or spiral and threadlike in shape, often clumped into colonies. Some bacteria cause disease, whereas 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. Bankfull stage, as used in this report, is the stage at which a stream first overflows its natural banks formed by floods with 1- to 3-year recurrence intervals. Base discharge (for peak discharge) is a discharge value, determined for selected stations, above which peak discharge data are published. The base discharge at each station is selected so that an average of about three peak flows per year will be published. (See also “Peak flow”) Base flow is sustained flow of a stream in the absence of direct runoff. It includes natural and human-induced streamflows. Natural base flow is sustained largely by ground-water discharge. Bedload is material in transport that is supported primarily by the streambed. In this report, bedload is considered to consist of particles in transit from the bed to an elevation equal to the top of the bedload sampler nozzle (ranging from 0.25 to 0.5 foot) that are retained in the bedload sampler. A sample collected with a pressure-differential bedload sampler also may contain a component of the suspended load. Bedload discharge (tons per day) is the rate of sediment moving as bedload, reported as dry weight, that passes through a cross section in a given time. NOTE: Bedload discharge values in this report may include a component of the suspended-sediment discharge. A correction may be necessary when computing the total sediment discharge by summing the bedload discharge and the suspended-sediment discharge. (See also “Bedload,” “Dry weight,” “Sediment,” and “Suspended-sediment discharge”) Bed material is the sediment mixture of which a stream-bed, lake, pond, reservoir, or estuary bottom is composed. (See also “Bedload” and “Sediment”) Benthic organisms are the group of organisms inhabiting the bottom of an aquatic environment. They include a number of types of organisms, such as bacteria, fungi, insect larvae and nymphs, snails, clams, and crayfish. They are useful as indicators of water quality. 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 mass per unit area or volume of habitat. Biomass pigment ratio is an indicator of the total proportion of periphyton that are autotrophic (plants). This is also called the Autotrophic Index. Blue-green algae (Cyanophyta) 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. Concentrations are expressed as a number of cells per milliliter (cells/mL) of sample. (See also “Phytoplankton”) Bottom material (See “Bed material”) Bulk electrical conductivity is the combined electrical conductivity of all material within a doughnut-shaped volume surrounding an induction probe. Bulk conductivity is affected by different physical and chemical properties of the material including the dissolved solids content of the pore water and lithology and porosity of the rock. Cells/volume refers to the number of cells of any organism that 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 volume, and are generally reported as cells or units per milliliter (mL) or liter (L). 33 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 Cells volume (biovolume) determination is one of several common methods used to estimate biomass of algae in aquatic systems. Cell members of algae are frequently used in aquatic surveys as an indicator of algal production. However, cell numbers alone cannot represent true biomass because of considerable cell-size variation among the algal species. Cell volume (µm3) is determined by obtaining critical cell measurements or cell dimensions (for example, length, width, height, or radius) for 20 to 50 cells of each important species to obtain an average biovolume per cell. Cells are categorized according to the correspondence of their cellular shape to the nearest geometric solid or combinations of simple solids (for example, spheres, cones, or cylinders). Representative formulae used to compute biovolume are as follows: sphere 4/3 πr3 cone 1/3 πr2h cylinder πr2h. pi (π) is the ratio of the circumference to the diameter of a circle; pi = 3.14159…. From cell volume, total algal biomass expressed as biovolume (µm3/mL) is thus determined by multiplying the number of cells of a given species by its average cell volume and then summing these volumes for all species. Cfs-day (See “Cubic foot per second-day”) Channel bars, as used in this report, are the lowest prominent geomorphic features higher than the channel bed. 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 BOD or with carbonaceous organic pollution from sewage or industrial wastes. [See also “Biochemical oxygen demand (BOD)”] Clostridium perfringens (C. perfringens) is a spore-forming bacterium that is common in the feces of human and other warmblooded animals. Clostridial spores are being used experimentally as an indicator of past fecal contamination and presence of microorganisms that are resistant to disinfection and environmental stresses. (See also “Bacteria”) Coliphages are viruses that infect and replicate in coliform bacteria. They are indicative of sewage contamination of water and of the survival and transport of viruses in the environment. Color unit is produced by 1 milligram per liter of platinum in the form of the chloroplatinate ion. Color is expressed in units of the platinum-cobalt scale. Confined aquifer is a term used to describe an aquifer containing water between two relatively impermeable bound- aries. The water level in a well tapping a confined aquifer stands above the top of the confined aquifer and can be higher or lower than the water table that may be present in the material above it. In some cases, the water level can rise above the ground surface, yielding a flowing well. 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. Continuous-record station is a site where data are collected with sufficient frequency to define daily mean values and variations within a day. Control designates a feature in the channel that physically affects the water-surface elevation and thereby determines the stage-discharge relation at the gage. This feature may be a constriction of the channel, a bedrock outcrop, a gravel bar, 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 saltwater. Cubic foot per second (CFS, ft3/s) is the rate of discharge representing a volume of 1 cubic foot passing a given point in 1 second. It is equivalent to approximately 7.48 gallons per second or approximately 449 gallons per minute, or 0.02832 cubic meters per second. The term “second-foot” sometimes is used synonymously with “cubic foot per second” but is now obsolete. 34 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 Cubic foot per second-day (CFS-DAY, Cfs-day, [(ft3/s)/d]) 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, 1.98347 acre-feet, 646,317 gallons, or 2,446.6 cubic meters. The daily mean discharges reported in the daily value data tables are numerically equal to the daily volumes in cfs-days, and the totals also represent volumes in cfs-days. Cubic foot per second per square mile [CFSM, (ft3/s)/mi2] 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. (See also “Annual runoff”) Daily mean suspended-sediment concentration is the time-weighted concentration of suspended sediment passing a stream cross section during a 24-hour day. (See also “Sediment” and “Suspended-sediment concentration”) Daily-record station is a site where data are collected with sufficient frequency to develop a record of one or more data values per day. The frequency of data collection can range from continuous recording to periodic sample or data collection on a daily or near-daily basis. Data collection platform (DCP) is an electronic instrument that collects, processes, and stores data from various sensors, and transmits the data by satellite data relay, line-of-sight radio, and/or landline telemetry. Data logger is a microprocessor-based data acquisition system designed specifically to acquire, process, and store data. Data are usually downloaded from onsite data loggers for entry into office data systems. Datum is a surface or point relative to which measurements of height and/or horizontal position are reported. A vertical datum is a horizontal surface used as the zero point for measurements of gage height, stage, or elevation; a horizontal datum is a reference for positions given in terms of latitude-longitude, State Plane coordinates, or UTM coordinates. (See also “Gage datum,” “Land-surface datum,” “National Geodetic Vertical Datum of 1929,” and “North American Vertical Datum of 1988”) 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. (See also “Phytoplankton”) Diel is of or pertaining to a 24-hour period of time; a regular daily cycle. Discharge, or flow, is the rate that matter passes through a cross section of a stream channel or other water body per unit of time. The term commonly refers to the volume of water (including, unless otherwise stated, any sediment or other constituents suspended or dissolved in the water) that passes a cross section in a stream channel, canal, pipeline, etc., within a given period of time (cubic feet per second). Discharge also can apply to the rate at which constituents, such as suspended sediment, bedload, and dissolved or suspended chemicals, pass through a cross section, in which cases the quantity is expressed as the mass of constituent that passes the cross section in a given period of time (tons per day). Dissolved refers to that material in a representative water sample that passes through a 0.45-micrometer membrane filter. This is a convenient operational definition used by Federal and State agencies that collect water-quality data. Determinations of “dissolved” constituent concentrations are made on sample water that has been filtered. Dissolved oxygen (DO) is the molecular oxygen (oxygen gas) dissolved in water. The concentration in water is a function of atmospheric pressure, temperature, and dissolved-solids concentration of the water. The ability of water to retain oxygen decreases with increasing temperature or dissolved-solids concentration. Photosynthesis and respiration by plants commonly cause diurnal variations in dissolved-oxygen concentration in water from some streams. Dissolved-solids concentration in water is the quantity of dissolved material in a sample of water. It is determined either analytically by the “residue-on-evaporation” method, or mathematically by totaling the concentrations of individual constituents reported in a comprehensive chemical analysis. During the analytical determination, the bicarbonate (generally a major dissolved component of water) is converted to carbonate. In the mathematical calculation, the bicarbonate value, in milligrams per liter, is multiplied by 0.4926 to convert it to carbonate. Alternatively, alkalinity concentration (as mg/L CaCO3) can be converted to carbonate concentration by multiplying by 0.60. 35 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 Diversity index (H) (Shannon index) is a numerical expression of evenness of distribution of aquatic organisms. The formula for diversity index is: , 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. 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 specific location is that area upstream from the location, measured in a horizontal plane, that has a common outlet at the site for its surface runoff from precipitation that normally drains by gravity into a stream. Drainage areas given herein include all closed basins, or noncontributing areas, within the area unless otherwise specified. Drainage basin is a part of the Earth’s surface that contains a drainage system with a common outlet for its surface runoff. (See “Drainage area”) Dry mass refers to the mass of residue present after drying in an oven at 105 °C, 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. (See also “Ash mass,” “Biomass,” and “Wet mass”) Dry weight refers to the weight of animal tissue after it has been dried in an oven at 65 °C until a constant weight is achieved. Dry weight represents total organic and inorganic matter in the tissue. (See also “Wet weight”) Embeddedness is the degree to which gravel-sized and larger particles are surrounded or enclosed by finer-sized particles. (See also “Substrate embeddedness class”) Enterococcus bacteria are commonly found in the feces of humans and other warmblooded animals. Although some strains are ubiquitous and not related to fecal pollution, the presence of enterococci in water is an indication of fecal pollution and the possible presence of enteric pathogens. Enterococcus bacteria are those bacteria that produce pink to red colonies with black or reddish-brown precipitate after incubation at 41 °C on mE agar (nutrient medium for bacterial growth) and subsequent transfer to EIA medium. Enterococci include Streptococcus feacalis, Streptococcus feacium, Streptococcus avium, and their variants. (See also “Bacteria”) EPT Index is the total number of distinct taxa within the insect orders Ephemeroptera, Plecoptera, and Trichoptera. This index summarizes the taxa richness within the aquatic insects that are generally considered pollution sensitive; the index usually decreases with pollution. Escherichia coli (E. coli) are bacteria present in the intestine and feces of warmblooded animals. E. coli are a member species of the fecal coliform group of indicator bacteria. In the laboratory, they are defined as those bacteria that produce yellow or yellow-brown colonies on a filter pad saturated with urea substrate broth after primary culturing for 22 to 24 hours at 44.5 °C on mTEC medium (nutrient medium for bacterial growth). Their concentrations are expressed as number of colonies per 100 mL of sample. (See also “Bacteria”) Estimated (E) concentration value is reported when an analyte is detected and all criteria for a positive result are met. If the concentration is less than the method detection limit (MDL), an ‘E’ code will be reported with the value. If the analyte is qualitatively identified as present, but the quantitative determination is substantially more uncertain, the National Water Quality Laboratory will identify the result with an ‘E’ code even though the measured value is greater than the MDL. A value reported with an ‘E’ code should be used with caution. When no analyte is detected in a sample, the default reporting value is the MDL preceded by a less than sign (<). Euglenoids (Euglenophyta) are a group of algae that are usually free-swimming and rarely creeping. They have the ability to grow either photosynthetically in the light or heterotrophically in the dark. (See also “Phytoplankton”) n n n n d i s i i 2 1 log ∑ ≈ − = 36 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 Extractable organic halides (EOX) are organic compounds that contain halogen atoms such as chlorine. These organic compounds are semivolatile and extractable by ethyl acetate from air-dried streambed sediment. The ethyl acetate extract is combusted, and the concentration is determined by microcoulometric determination of the halides formed. The concentration is reported as micrograms of chlorine per gram of the dry weight of the streambed sediment. Fecal coliform bacteria are present in the intestines or feces of warmblooded animals. They often are used as indicators of the sanitary quality of the water. In the laboratory, they are defined as all organisms that produce blue colonies within 24 hours when incubated at 44.5 °C plus or minus 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. (See also “Bacteria”) Fecal streptococcal bacteria are present in the intestines of warmblooded animals and are ubiquitous in the environment. They are characterized as gram-positive, cocci bacteria that are capable of growth in brain-heart infusion broth. In the laboratory, they are defined as all the organisms that produce red or pink colonies within 48 hours at 35 °C plus or minus 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. (See also “Bacteria”) Fire algae (Pyrrhophyta) are free-swimming unicells characterized by a red pigment spot. (See also “Phytoplankton”) Flow-duration percentiles are values on a scale of 100 that indicate the percentage of time for which a flow is not exceeded. For example, the 90th percentile of river flow is greater than or equal to 90 percent of all recorded flow rates. Gage datum is a horizontal surface used as a zero point for measurement of stage or gage height. This surface usually is located slightly below the lowest point of the stream bottom such that the gage height is usually slightly greater than the maximum depth of water. Because the gage datum itself is not an actual physical object, the datum usually is defined by specifying the elevations of permanent reference marks such as bridge abutments and survey monuments, and the gage is set to agree with the reference marks. Gage datum is a local datum that is maintained independently of any national geodetic datum. However, if the elevation of the gage datum relative to the national datum (North American Vertical Datum of 1988 or National Geodetic Vertical Datum of 1929) has been determined, then the gage readings can be converted to elevations above the national datum by adding the elevation of the gage datum to the gage reading. Gage height (G.H.) is the water-surface elevation, in feet above the gage datum. If the water surface is below the gage datum, the gage height is negative. Gage height often is used interchangeably with the more general term “stage,” although gage height is more appropriate when used in reference to a reading on a gage. Gage values are values that are recorded, transmitted, and/or computed from a gaging station. Gage values typically are collected at 5-, 15-, or 30-minute intervals. Gaging station is a site on a stream, canal, lake, or reservoir where systematic observations of stage, discharge, or other hydrologic data are obtained. Gas chromatography/flame ionization detector (GC/FID) is a laboratory analytical method used as a screening technique for semivolatile organic compounds that are extractable from water in methylene chloride. Geomorphic channel units, as used in this report, are fluvial geomorphic descriptors of channel shape and stream velocity. Pools, riffles, and runs are types of geomorphic channel units considered for National Water-Quality Assessment (NAWQA) Program habitat sampling. 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. (See also “Phytoplankton”) Habitat, as used in this report, includes all nonliving (physical) aspects of the aquatic ecosystem, although living components like aquatic macrophytes and riparian vegetation also are usually included. Measurements of habitat are typically made over a wider geographic scale than are measurements of species distribution. 37 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 Habitat quality index is the qualitative description (level 1) of instream habitat and riparian conditions surrounding the reach sampled. Scores range from 0 to 100 percent with higher scores indicative of desirable habitat conditions for aquatic life. Index only applicable to wadable streams. Hardness of water is a physical-chemical characteristic that commonly is recognized by the increased quantity of soap required to produce lather. It is computed as the sum of equivalents of polyvalent cations (primarily calcium and magnesium) and is expressed as the equivalent concentration of calcium carbonate (CaCO3). High tide is the maximum height reached by each rising tide. The high-high and low-high tides are the higher and lower of the two high tides, respectively, of each tidal day. See NOAA web site: http://www.co-ops.nos.noaa.gov/tideglos.html Hilsenhoff’s Biotic Index (HBI) is an indicator of organic pollution that uses tolerance values to weight taxa abundances; usually increases with pollution. It is calculated as follows: , where n is the number of individuals of each taxon, a is the tolerance value of each taxon, and N is the total number of organisms in the sample. Horizontal datum (See “Datum”) Hydrologic index stations referred to in this report are continuous-record gaging stations that have been selected as representative of streamflow patterns for their respective regions. Station locations are shown on index maps. Hydrologic unit is a geographic area representing part or all of a surface drainage basin or distinct hydrologic feature as defined by the former Office of Water Data Coordination and delineated on the State Hydrologic Unit Maps by the USGS. Each hydrologic unit is identified by an 8-digit number. Inch (IN., in.), as used in this report, refers to the depth to which the drainage area would be covered with water if all of the runoff for a given time period were uniformly distributed on it. (See also “Annual runoff”) Instantaneous discharge is the discharge at a particular instant of time. (See also “Discharge”) Island, as used in this report, is a mid-channel bar that has permanent woody vegetation, is flooded once a year on average, and remains stable except during large flood events. Laboratory reporting level (LRL) is generally equal to twice the yearly determined long-term method detection level (LT-MDL). The LRL controls false negative error. The probability of falsely reporting a nondetection for a sample that contained an analyte at a concentration equal to or greater than the LRL is predicted to be less than or equal to 1 percent. The value of the LRL will be reported with a “less than” (<) remark code for samples in which the analyte was not detected. The National Water Quality Laboratory (NWQL) collects quality-control data from selected analytical methods on a continuing basis to determine LT-MDLs and to establish LRLs. These values are reevaluated annually on the basis of the most current quality-control data and, therefore, may change. [Note: In several previous NWQL documents (NWQL Technical Memorandum 98.07, 1998), the LRL was called the nondetection value or NDV—a term that is no longer used.] Land-surface datum (lsd) is a datum plane that is approximately at land surface at each ground-water observation well. Latent heat flux (often used interchangeably with latent heat-flux density) is the amount of heat energy that converts water from liquid to vapor (evaporation) or from vapor to liquid (condensation) across a specified cross-sectional area per unit time. Usually expressed in watts per square meter. N a n sum HBI ) )( ( = 38 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 Light-attenuation coefficient, also known as the extinction coefficient, is a measure of water clarity. Light is attenuated according to the Lambert-Beer equation: , where Io is the source light intensity, I is the light intensity at length L (in meters) from the source, λ is the light- attenuation coefficient, and e is the base of the natural logarithm. The light-attenuation coefficient is defined as . Lipid is any one of a family of compounds that are insoluble in water and that make up one of the principal components of living cells. Lipids include fats, oils, waxes, and steroids. Many environmental contaminants such as organochlorine pesticides are lipophilic. Long-term method detection level (LT-MDL) is a detection level derived by determining the standard deviation of a minimum of 24 method detection limit (MDL) spike sample measurements over an extended period of time. LT- MDL data are collected on a continuous basis to assess year-to-year variations in the LT-MDL. The LT-MDL controls false positive error. The chance of falsely reporting a concentration at or greater than the LT-MDL for a sample that did not contain the analyte is predicted to be less than or equal to 1 percent. Low tide is the minimum height reached by each falling tide. The high-low and low-low tides are the higher and lower of the two low tides, respectively, of each tidal day. See NOAA web site: http://www.co-ops.nos.noaa.gov/tideglos.html Macrophytes are the macroscopic plants in the aquatic environment. The most common macrophytes are the rooted vascular plants that usually are arranged in zones in aquatic ecosystems and restricted in the area by the extent of illumination through the water and sediment deposition along the shoreline. Mean concentration of suspended sediment (Daily mean suspended-sediment concentration) is the time-weighted concentration of suspended sediment passing a stream cross section during a given time period. (See also “Daily mean suspended-sediment concentration” and “Suspended-sediment concentration”) Mean discharge (MEAN) is the arithmetic mean of individual daily mean discharges during a specific period. (See also “Discharge”) Mean high or low tide is the average of all high or low tides, respectively, over a specific period. Mean sea level is a local tidal datum. It is the arithmetic mean of hourly heights observed over the National Tidal Datum Epoch. Shorter series are specified in the name; for example, monthly mean sea level and yearly mean sea level. In order that they may be recovered when needed, such datums are referenced to fixed points known as benchmarks. (See also “Datum”) Measuring point (MP) is an arbitrary permanent reference point from which the distance to water surface in a well is measured to obtain water level. Membrane filter is a thin microporous material of specific pore size used to filter bacteria, algae, and other very small particles from water. Metamorphic stage refers to the stage of development that an organism exhibits during its transformation from an immature form to an adult form. This developmental process exists for most insects, and the degree of difference from the immature stage to the adult form varies from relatively slight to pronounced, with many intermediates. Examples of metamorphic stages of insects are egg-larva-adult or egg-nymph-adult. Method detection limit (MDL) is the minimum concentration of a substance that can be measured and reported with 99-percent confidence that the analyte concentration is greater than zero. It is determined from the analysis of a sample in a given matrix containing the analyte. At the MDL concentration, the risk of a false positive is predicted to be less than or equal to 1 percent. L oe I I λ − = o e I I Llog 1 − = λ 39 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 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, µg/g) is a unit expressing the concentration of a chemical constituent as the mass (micrograms) of the element per unit mass (gram) of material analyzed. Micrograms per kilogram (UG/KG, µg/kg) is a unit expressing the concentration of a chemical constituent as the mass (micrograms) of the constituent per unit mass (kilogram) of the material analyzed. One microgram per kilogram is equivalent to 1 part per billion. Micrograms per liter (UG/L, µg/L) is a unit expressing the concentration of chemical constituents in water as mass (micrograms) of constituent per unit volume (liter) of water. One thousand micrograms per liter is equivalent to 1 milligram per liter. One microgram per liter is equivalent to 1 part per billion. Microsiemens per centimeter (US/CM, µS/cm) is a unit expressing the amount of electrical conductivity of a solution as measured between opposite faces of a centimeter cube of solution at a specified temperature. Siemens is the International System of Units nomenclature. It is synonymous with mhos and is the reciprocal of resistance in ohms. Milligrams per liter (MG/L, mg/L) is a unit for expressing the concentration of chemical constituents in water as the mass (milligrams) of constituent per unit volume (liter) of water. Concentration of suspended sediment also is expressed in milligrams per liter and is based on the mass of dry sediment per liter of water-sediment mixture. Minimum reporting level (MRL) is the smallest measured concentration of a constituent that may be reliably reported by using a given analytical method. Miscellaneous site, miscellaneous station, or miscellaneous sampling site is a site where streamflow, sediment, and/ or water-quality data or water-quality or sediment samples are collected once, or more often on a random or discontinuous basis to provide better areal coverage for defining hydrologic and water-quality conditions over a broad area in a river basin. Most probable number (MPN) is an index of the number of coliform bacteria that, more probably than any other number, would give the results shown by the laboratory examination; it is not an actual enumeration. MPN is determined from the distribution of gas-positive cultures among multiple inoculated tubes. Multiple-plate samplers are artificial substrates of known surface area used for obtaining benthic invertebrate samples. They consist of a series of spaced, hardboard plates on an eyebolt. Nanograms per liter (NG/L, ng/L) is a unit expressing the concentration of chemical constituents in solution as mass (nanograms) of solute per unit volume (liter) of water. One million nanograms per liter is equivalent to 1 milligram per liter. National Geodetic Vertical Datum of 1929 (NGVD of 1929) is a fixed reference adopted as a standard geodetic datum for elevations determined by leveling. It was formerly called “Sea Level Datum of 1929” or “mean sea level.” Although the datum was derived from the mean sea level at 26 tide stations, it does not necessarily represent local mean sea level at any particular place. See NOAA web site: http://www.ngs.noaa.gov/ faq.shtml#WhatVD29VD88 (See “North American Vertical Datum of 1988”) Natural substrate refers to any naturally occurring immersed or submersed solid surface, such as a rock or tree, upon which an organism lives. (See also “Substrate”) Nekton are the consumers in the aquatic environment and consist of large free-swimming organisms that are capable of sustained, directed mobility. Nephelometric turbidity unit (NTU) is the measurement for reporting turbidity that is based on use of a standard suspension of formazin. Turbidity measured in NTU uses nephelometric methods that depend on passing specific light of a specific wavelength through the sample. 40 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 North American Vertical Datum of 1988 (NAVD 1988) is a fixed reference adopted as the official civilian vertical datum for elevations determined by Federal surveying and mapping activities in the United States. This datum was established in 1991 by minimum-constraint adjustment of the Canadian, Mexican, and United States first- order terrestrial leveling networks. Open or screened interval is the length of unscreened opening or of well screen through which water enters a well, in feet below land surface. Organic carbon (OC) is a measure of organic matter present in aqueous solution, suspension, or bottom sediment. May be reported as dissolved organic carbon (DOC), particulate organic carbon (POC), or total organic carbon (TOC). Organic mass or volatile mass of a living substance is the difference between the dry mass and ash mass and represents the actual mass of the living matter. Organic mass is expressed in the same units as for ash mass and dry mass. (See also “Ash mass,” “Biomass,” and “Dry mass”) Organism count/area refers to the number of organisms collected and enumerated in a sample and adjusted to the number per area habitat, usually square meter (m2), acre, 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 milliliter (mL) or liter (L). Numbers of planktonic organisms can be expressed in these terms. Organochlorine compounds are any chemicals that contain carbon and chlorine. Organochlorine compounds that are important in investigations of water, sediment, and biological quality include certain pesticides and industrial compounds. Parameter code is a 5-digit number used in the USGS computerized data system, National Water Information System (NWIS), to uniquely identify a specific constituent or property. Partial-record station is a site where discrete measurements of one or more hydrologic parameters are obtained over a period of time without continuous data being recorded or computed. A common example is a crest-stage gage partial-record station at which only peak stages and flows are recorded. Particle size is the diameter, in millimeters (mm), of a particle determined by sieve or sedimentation methods. The sedimentation method utilizes the principle of Stokes law to calculate sediment particle sizes. Sedimentation methods (pipet, bottom-withdrawal tube, visual-accumulation tube, sedigraph) 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, as used in this report, agrees with the recommendation 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 >0.004 - 0.062 Sedimentation Sand >0.062 - 2.0 Sedimentation/sieve Gravel >2.0 - 64.0 Sieve Cobble >64 - 256 Manual measurement Boulder >256 Manual measurement The particle-size distributions given in this report are not necessarily representative of all particles in transport in the stream. For the sedimentation method, 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. 41 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 Peak flow (peak stage) is an instantaneous local maximum value in the continuous time series of streamflows or stages, preceded by a period of increasing values and followed by a period of decreasing values. Several peak values ordinarily occur in a year. The maximum peak value in a year is called the annual peak; peaks lower than the annual peak are called secondary peaks. Occasionally, the annual peak may not be the maximum value for the year; in such cases, the maximum value occurs at midnight at the beginning or end of the year, on the recession from or rise toward a higher peak in the adjoining year. If values are recorded at a discrete series of times, the peak recorded value may be taken as an approximation of the true peak, which may occur between the recording instants. If the values are recorded with finite precision, a sequence of equal recorded values may occur at the peak; in this case, the first value is taken as the peak. Percent composition or percent of total 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, weight, mass, or volume. Percent shading is a measure of the amount of sunlight potentially reaching the stream. A clinometer is used to measure left and right bank canopy angles. These values are added together, divided by 180, and multiplied by 100 to compute percentage of shade. Periodic-record station is a site where stage, discharge, sediment, chemical, physical, or other hydrologic measurements are made one or more times during a year but at a frequency insufficient to develop a daily record. Periphyton is the assemblage of microorganisms attached to and living upon submerged solid surfaces. Although primarily consisting of algae, they also include bacteria, fungi, protozoa, rotifers, and other small organisms. Periphyton are useful indicators of water quality. Pesticides are chemical compounds used to control undesirable organisms. Major categories of pesticides include insecticides, miticides, fungicides, herbicides, and rodenticides. pH of water is the negative logarithm of the hydrogen-ion activity. Solutions with pH less than 7.0 standard units are termed “acidic,” and solutions with a pH greater than 7.0 are termed “basic.” Solutions with a pH of 7.0 are neutral. The presence and concentration of many dissolved chemical constituents found in water are affected, in part, by the hydrogen-ion activity of water. Biological processes including growth, distribution of organisms, and toxicity of the water to organisms also are affected, in part, by the hydrogen-ion activity of water. 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 commonly are known as algae. (See also “Plankton”) Picocurie (PC, pCi) is one trillionth (1 x 10-12) of the amount of radioactive nuclide represented by a curie (Ci). A curie is the quantity of radioactive nuclide that yields 3.7 x 1010 radioactive disintegrations per second (dps). A picocurie yields 0.037 dps, or 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. Concentrations are expressed as a number of cells per milliliter (cells/mL) of sample. 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. Polychlorinated naphthalenes (PCNs) are industrial chemicals that are mixtures of chlorinated naphthalene compounds. They have properties and applications similar to polychlorinated biphenyls (PCBs) and have been identified in commercial PCB preparations. Pool, as used in this report, is a small part of a stream reach with little velocity, commonly with water deeper than surrounding areas. Primary productivity is a measure of the rate at which new organic matter is formed and accumulated through photo-synthetic 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 (carbon method) by the plants. 42 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 Primary productivity (carbon method) is expressed as milligrams of carbon per area per unit time [mg C/(m2/time)] for periphyton and macrophytes or per volume [mg C/(m3/time)] for phytoplankton. The carbon method defines 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 with unenriched water samples. Unit time may be either the hour or day, depending on the incubation period. (See also “Primary productivity”) Primary productivity (oxygen method) is expressed as milligrams of oxygen per area per unit time [mg O/(m2/ time)] for periphyton and macrophytes or per volume [mg O/(m3/time)] for phytoplankton. The oxygen method defines 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. (See also “Primary productivity”) Radioisotopes are isotopic forms of elements that exhibit radioactivity. Isotopes are varieties of a chemical element that differ in atomic weight but are very nearly alike in chemical properties. The difference arises because the atoms of the isotopic forms of an element differ in the number of neutrons in the nucleus; for example, ordinary chlorine is a mixture of isotopes having atomic weights of 35 and 37, and the natural mixture has an atomic weight of about 35.453. Many of the elements similarly exist as mixtures of isotopes, and a great many new isotopes have been produced in the operation of nuclear devices such as the cyclotron. There are 275 isotopes of the 81 stable elements, in addition to more than 800 radioactive isotopes. Reach, as used in this report, is a length of stream that is chosen to represent a uniform set of physical, chemical, and biological conditions within a segment. It is the principal sampling unit for collecting physical, chemical, and biological data. Recoverable from bed (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. (See also “Bed material”) Recurrence interval, also referred to as return period, is the average time, usually expressed in years, between occurrences of hydrologic events of a specified type (such as exceedances of a specified high flow or nonexceedance of a specified low flow). The terms “return period” and “recurrence interval” do not imply regular cyclic occurrence. The actual times between occurrences vary randomly, with most of the times being less than the average and a few being substantially greater than the average. For example, the 100-year flood is the flow rate that is exceeded by the annual maximum peak flow at intervals whose average length is 100 years (that is, once in 100 years, on average); almost two-thirds of all exceedances of the 100-year flood occur less than 100 years after the previous exceedance, half occur less than 70 years after the previous exceedance, and about one-eighth occur more than 200 years after the previous exceedance. Similarly, the 7-day, 10-year low flow (7Q10) is the flow rate below which the annual minimum 7-day-mean flow dips at intervals whose average length is 10 years (that is, once in 10 years, on average); almost two-thirds of the nonexceedances of the 7Q10 occur less than 10 years after the previous nonexceedance, half occur less than 7 years after, and about one-eighth occur more than 20 years after the previous nonexceedance. The recurrence interval for annual events is the reciprocal of the annual probability of occurrence. Thus, the 100-year flood has a 1-percent chance of being exceeded by the maximum peak flow in any year, and there is a 10-percent chance in any year that the annual minimum 7- day-mean flow will be less than the 7Q10. Replicate samples are a group of samples collected in a manner such that the samples are thought to be essentially identical in composition. Return period (See “Recurrence interval”) 43 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 Riffle, as used in this report, is a shallow part of the stream where water flows swiftly over completely or partially submerged obstructions to produce surface agitation. River mileage is the curvilinear distance, in miles, measured upstream from the mouth along the meandering path of a stream channel in accordance with Bulletin No. 14 (October 1968) of the Water Resources Council and typically is used to denote location along a river. Run, as used in this report, is a relatively shallow part of a stream with moderate velocity and little or no surface turbulence. Runoff is the quantity of water that is discharged (“runs off”) from a drainage basin during a given time period. Runoff data may be presented as volumes in acre-feet, as mean discharges per unit of drainage area in cubic feet per second per square mile, or as depths of water on the drainage basin in inches. (See also “Annual runoff”) Sea level, as used in this report, refers to one of the two commonly used national vertical datums (NGVD 1929 or NAVD 1988). See separate entries for definitions of these datums. Sediment is solid material that originates mostly from disintegrated rocks; when transported by, suspended in, or deposited from water, it is referred to as “fluvial sediment.” Sediment 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 affected by environmental and land-use factors. Some major factors are topography, soil characteristics, land cover, and depth and intensity of pre-cipitation. Sensible heat flux (often used interchangeably with latent sensible heat-flux density) is the amount of heat energy that moves by turbulent transport through the air across a specified cross-sectional area per unit time and goes to heating (cooling) the air. Usually expressed in watts per square meter. Seven-day, 10-year low flow (7Q10) is the discharge below which the annual 7-day minimum flow falls in 1 year out of 10 on the long-term average. The recurrence interval of the 7Q10 is 10 years; the chance that the annual 7-day minimum flow will be less than the 7Q10 is 10 percent in any given year. (See also “Annual 7-day minimum” and “Recurrence interval”) Shelves, as used in this report, are streambank features extending nearly horizontally from the flood plain to the lower limit of persistent woody vegetation. 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. Sodium hazard in water is an index that can be used to evaluate the suitability of water for irrigating crops. Soil heat flux (often used interchangeably with soil heat-flux density) is the amount of heat energy that moves by conduction across a specified cross-sectional area of soil per unit time and goes to heating (or cooling) the soil. Usually expressed in watts per square meter. Soil-water content is the water lost from the soil upon drying to constant mass at 105 °C; expressed either as mass of water per unit mass of dry soil or as the volume of water per unit bulk volume of soil. Specific electrical conductance (conductivity) is a measure of the capacity of water (or other media) to conduct an electrical current. It is expressed in microsiemens per centimeter at 25 °C. Specific electrical conductance is a function of the types and quantity of dissolved substances in water and can be used for approximating the dissolved-solids content of the water. Commonly, the concentration of dissolved solids (in milligrams per liter) is from 55 to 75 percent of the specific conductance (in microsiemens). 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. Stable isotope ratio (per MIL) is a unit expressing the ratio of the abundance of two radioactive isotopes. Isotope ratios are used in hydrologic studies to determine the age or source of specific water, to evaluate mixing of different water, as an aid in determining reaction rates, and other chemical or hydrologic processes. Stage (See “Gage height”) 44 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 Stage-discharge relation is the relation between the water-surface elevation, termed stage (gage height), and the volume of water flowing in a channel per unit time. Streamflow is the discharge that occurs in a natural channel. Although the term “discharge” can be applied to the flow of a canal, the word “streamflow” uniquely describes the discharge in a surface stream course. The term “streamflow” is more general than “runoff” as streamflow may be applied to discharge whether or not it is affected by diversion or regulation. Substrate is the physical surface upon which an organism lives. Substrate embeddedness class is a visual estimate of riffle streambed substrate larger than gravel that is surrounded or covered by fine sediment (<2mm, sand or finer). Below are the class categories expressed as the percentage covered by fine sediment: 0 no gravel or larger substrate 3 26-50 percent 1 > 75 percent 4 5-25 percent 2 51-75 percent 5 < 5 percent Surface area of a lake is that area (acres) encompassed by the boundary of the lake as shown on USGS topographic maps, or other available maps or photographs. Because surface area changes with lake stage, surface areas listed in this report represent those determined for the stage at the time the maps or photographs were obtained. Surficial bed material is the upper surface (0.1 to 0.2 foot) 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 undissolved material in a water-sediment mixture. It is defined operationally as 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 suspended water-sediment sample that is retained on a 0.45-micrometer 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 directly analyzing the suspended mate-rial collected on the filter or, more commonly, by difference, on the basis of determinations of (1) dissolved and (2) total recoverable concentrations of the constituent. (See also “Suspended”) Suspended sediment is the sediment maintained in suspension by the upward components of turbulent currents or that exists in suspension as a colloid. (See also “Sediment”) 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 foot above the bed) expressed as milligrams of dry sediment per liter of water-sediment mixture (mg/L). The analytical technique uses the mass of all of the sediment and the net weight of the water-sediment mixture in a sample to compute the suspended-sediment concentration. (See also “Sediment” and “Suspended sediment”) Suspended-sediment discharge (tons/d) is the rate of sediment transport, as measured by dry mass or volume, that passes a cross section in a given time. It is calculated in units of tons per day as follows: concentration (mg/L) x discharge (ft3/s) x 0.0027. (See also “Sediment,” “Suspended sediment,” and “Suspended-sediment concentration”) Suspended-sediment load is a general term that refers to a given characteristic of the material in suspension that passes a point during a specified period of time. The term needs to be qualified, such as “annual suspended- sediment load” or “sand-size suspended-sediment load,” and so on. It is not synonymous with either suspended- sediment discharge or concentration. (See also “Sediment”) 45 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 Suspended, total is the total amount of a given constituent in the part of a water-sediment sample that is retained on a 0.45-micrometer membrane filter. This term is used only when the analytical procedure assures measurement of at least 95 percent of the constituent determined. 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 directly analyzing portions of the suspended material collected on the filter or, more commonly, by difference, on the basis of determinations of (1) dissolved and (2) total concentrations of the constituent. (See also “Suspended”) Suspended solids, total residue at 105 °C concentration is the concentration of inorganic and organic material retained on a filter, expressed as milligrams of dry material per liter of water (mg/L). An aliquot of the sample is used for this analysis. Synoptic studies are short-term investigations of specific water-quality conditions during selected seasonal or hydro- logic periods to provide improved spatial resolution for critical water-quality conditions. For the period and conditions sampled, they assess the spatial distribution of selected water-quality conditions in relation to causative factors, such as land use and contaminant sources. Taxa (Species) richness is the number of species (taxa) present in a defined area or sampling unit. 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: Arthropoda Class: Insecta Order: Ephemeroptera Family: Ephemeridae Genus: Hexagenia Species: Hexagenia limbata Thalweg is the line formed by connecting points of minimum streambed elevation (deepest part of the channel). Thermograph is an instrument that continuously records variations of temperature on a chart. The more general term “temperature recorder” is used in the table descriptions 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 resulting from the mixing of flow proportionally to the duration of the concentration. Tons per acre-foot (T/acre-ft) is the dry mass (tons) of a constituent per unit volume (acre-foot) of water. It is computed by multiplying the concentration of the constituent, in milligrams per liter, by 0.00136. Tons per day (T/DAY, tons/d) is a common chemical or sediment discharge unit. It is the quantity of a substance in solution, in suspension, or as bedload that passes a stream section during a 24-hour period. It is equivalent to 2,000 pounds per day, or 0.9072 metric tons per day. Total is the amount of a given constituent in a representative whole-water (unfiltered) 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 at least 95 percent of the constituent in the sample.) 46 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 Total coliform bacteria are a particular group of bacteria that are used as indicators of possible sewage pollution. This group includes coliforms that inhabit the intestine of warmblooded animals and those that inhabit soils. They are characterized as aerobic or facultative anaerobic, gram-negative, nonspore- forming, rod-shaped bacteria that ferment lactose with gas formation within 48 hours at 35 °C. In the laboratory, these bacteria are defined as all the organisms that produce colonies with a golden-green metallic sheen within 24 hours when incubated at 35 °C plus or minus 1.0 °C on M-Endo medium (nutrient medium for bacterial growth). Their concentrations are expressed as number of colonies per 100 milliliters of sample. (See also “Bacteria”) Total discharge is the quantity of a given constituent, measured as dry mass or volume, that passes a stream cross section per unit of time. When referring to constituents other than water, this term needs to be qualified, such as “total sediment discharge,” “total chloride discharge,” and so on. Total in bottom material is the amount of a given constituent in a representative sample of bottom material. 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 judge when the results should be reported as “total in bottom material.” Total length (fish) is the straight-line distance from the anterior point of a fish specimen’s snout, with the mouth closed, to the posterior end of the caudal (tail) fin, with the lobes of the caudal fin squeezed together. Total load refers to all of a constituent in transport. When referring to sediment, it includes suspended load plus bed load. Total organism count is the number of organisms collected and enumerated in any particular sample. (See also “Organism count/volume”) Total recoverable is the amount of a given constituent in a whole-water sample after a 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 for whole-water samples, equivalent digestion procedures are required of all laboratories performing such analyses because different digestion procedures may produce different analytical results. Total sediment discharge is the mass of suspended-sediment plus bed-load transport, measured as dry weight, that passes a cross section in a given time. It is a rate and is reported as tons per day. (See also “Bedload,” “Bedload discharge,” “Sediment,” “Suspended sediment,” and “Suspended-sediment concentration”) Total sediment load or total load is the sediment in transport as bedload and suspended-sediment load. The term may be qualified, such as “annual suspended-sediment load” or “sand-size suspended-sediment load,” and so on. It differs from total sediment discharge in that load refers to the material, whereas discharge refers to the quantity of material, expressed in units of mass per unit time. (See also “Sediment,” “Suspended-sediment load,” and “Total load”) Transect, as used in this report, is a line across a stream perpendicular to the flow and along which measurements are taken, so that morphological and flow characteristics along the line are described from bank to bank. Unlike a cross section, no attempt is made to determine known elevation points along the line. 47 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 Turbidity is the reduction in the transparency of a solution due to the presence of suspended and some dissolved substances. The measurement technique records the collective optical properties of the solution that cause light to be scattered and attenuated rather than transmitted in straight lines; the higher the intensity of scattered or attenuated light, the higher the value of the turbidity. Turbidity is expressed in nephelometric turbidity units (NTU). Depending on the method used, the turbidity units as NTU can be defined as the intensity of light of a specified wavelength scattered or attenuated by suspended particles or absorbed at a method specified angle, usually 90 degrees, from the path of the incident light. Currently approved methods for the measurement of turbidity in the USGS include those that conform to U.S. EPA Method 180.1, ASTM D1889-00, and ISO 7027. Measurements of turbidity by these different methods and different instruments are unlikely to yield equivalent values. Ultraviolet (UV) absorbance (absorption) at 254 or 280 nanometers is a measure of the aggregate concentration of the mixture of UV absorbing organic materials dissolved in the analyzed water, such as lignin, tannin, humic substances, and various aromatic compounds. UV absorbance (absorption) at 254 or 280 nanometers is measured in UV absorption units per centimeter of pathlength of UV light through a sample. Unconfined aquifer is an aquifer whose upper surface is a water table free to fluctuate under atmospheric pressure. (See “Water-table aquifer”) Vertical datum (See “Datum”) Volatile organic compounds (VOCs) are organic compounds that can be isolated from the water phase of a sample by purging the water sample with inert gas, such as helium, and subsequently analyzed by gas chromatography. Many VOCs are human-made chemicals that are used and produced in the manufacture of paints, adhesives, petroleum products, pharmaceuticals, and refrigerants. They are often components of fuels, solvents, hydraulic fluids, paint thinners, and dry cleaning agents commonly used in urban settings. VOC contamination of drinking- water supplies is a human health concern because many are toxic and are known or suspected human carcinogens. Water table is that surface in a ground-water body at which the water pressure is equal to the atmospheric pressure. Water-table aquifer is an unconfined aquifer within which the water table is found. Water year in USGS 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, 2002, is called the “2002 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. Wet mass is the mass of living matter plus contained water. (See also “Biomass” and “Dry mass”) Wet weight refers to the weight of animal tissue or other substance including its contained water. (See also “Dry weight”) WSP is used as an acronym for “Water-Supply Paper” in reference to previously published reports. Zooplankton is the animal part of the plankton. Zooplankton are capable of extensive movements within the water column and often are 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. (See also “Plankton”) 48 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 TECHNIQUES OF WATER-RESOURCES INVESTIGATIONS OF THE U.S. GEOLOGICAL SURVEY The USGS publishes a series of manuals, the Techniques of Water-Resources Investigations, describing proce- dures for planning and conducting 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. Reports in the Techniques of Water-Resources Investigations series, which are listed below, are online at http:// water.usgs.gov/pubs/twri/. Printed copies are for sale by the USGS, Information Services, Box 25286, Federal Center, Denver, Colorado 80225 (authorized agent of the Superintendent of Documents, Government Printing Office), tele- phone 1-888-ASK-USGS. Please telephone 1-888-ASK-USGS for current prices, and refer to the title, book number, chapter number, and mention the “U.S. Geological Survey Techniques of Water-Resources Investigations.” Products can then be ordered by telephone, or online at http://www.usgs.gov/sales.html, or by FAX to (303)236-469 of an order form available online at http://mac.usgs.gov/isb/pubs/forms/. Prepayment by major credit card or by a check or money order payable to the “U.S. Geological Survey” is required. Book 1. Collection of Water Data by Direct Measurement Section D. Water Quality 1-D1. Water temperature—influential factors, field measurement, and data presentation, by H. H. Stevens, Jr., J.F. Ficke, and G. F. Smoot: USGS–TWRI book 1, chap. D1. 1975. 65 p. 1-D2. Guidelines for collection and field analysis of ground-water samples for selected unstable constituents, by W.W. Wood: USGS–TWRI book 1, chap. D2. 1976. 24 p. Book 2. Collection of Environmental Data Section D. Surface Geophysical Methods 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, chap. D1. 1974. 116 p. 2-D2. Application of seismic-refraction techniques to hydrologic studies, by F.P. Haeni: USGS–TWRI book 2, chap. D2. 1988. 86 p. Section E. Subsurface Geophysical Methods 2-E1. Application of borehole geophysics to water-resources investigations, by W.S. Keys and L.M. MacCary: USGS–TWRI book 2, chap. E1. 1971. 126 p. 2-E2. Borehole geophysics applied to ground-water investigations, by W.S. Keys: USGS–TWRI book 2, chap. E2. 1990. 150 p. Section F. Drilling and Sampling Methods 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, chap. F1. 1989. 97 p. Book 3. Applications of Hydraulics Section A. Surface-Water Techniques 3-A1. General field and office procedures for indirect discharge measurements, by M.A. Benson and Tate Dalrymple: USGS– TWRI book 3, chap. A1. 1967. 30 p. 3-A2. Measurement of peak discharge by the slope-area method, by Tate Dalrymple and M.A. Benson: USGS–TWRI book 3, chap. A2. 1967. 12 p. 3-A3. Measurement of peak discharge at culverts by indirect methods, by G.L. Bodhaine: USGS–TWRI book 3, chap. A3. 1968. 60 p. 3-A4. Measurement of peak discharge at width contractions by indirect methods, by H.F. Matthai: USGS-TWRI book 3, chap. A4. 1967. 44 p. 3-A5. Measurement of peak discharge at dams by indirect methods, by Harry Hulsing: USGS–TWRI book 3. chap. A5. 1967. 29 p. 49 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 PUBLICATIONS ON TECHNIQUES OF WATER-RESOURCES INVESTIGATIONS—Continued 3-A6. General procedure for gaging streams, by R.W. Carter and Jacob Davidian: USGS–TWRI book 3, chap. A6. 1968. 13 p. 3-A7. Stage measurement at gaging stations, by T.J. Buchanan and W.P. Somers: USGS–TWRI book 3, chap. A7. 1968. 28 p. 3-A8. Discharge measurements at gaging stations, by T.J. Buchanan and W.P. Somers: USGS–TWRI book 3, chap. A8. 1969. 65 p. 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, chap. A9. 1989. 27 p. 3-Al0. Discharge ratings at gaging stations, by E.J. Kennedy: USGS–TWRI book 3, chap. A10. 1984. 59 p. 3-A11. Measurement of discharge by the moving-boat method, by G.F. Smoot and C.E. Novak: USGS–TWRI book 3, chap. A11. 1969. 22 p. 3-A12. Fluorometric procedures for dye tracing, Revised, by J.F. Wilson, Jr., E.D. Cobb, and F.A. Kilpatrick: USGS–TWRI book 3, chap. A12. 1986. 34 p. 3-A13. Computation of continuous records of streamflow, by E.J. Kennedy: USGS–TWRI book 3, chap. A13. 1983. 53 p. 3-A14. Use of flumes in measuring discharge, by F.A. Kilpatrick and V.R. Schneider: USGS–TWRI book 3, chap. A14. 1983. 46 p. 3-A15. Computation of water-surface profiles in open channels, by Jacob Davidian: USGS–TWRI book 3, chap. A15. 1984. 48 p. 3-A16. Measurement of discharge using tracers, by F.A. Kilpatrick and E.D. Cobb: USGS–TWRI book 3, chap. A16. 1985. 52 p. 3-A17. Acoustic velocity meter systems, by Antonius Laenen: USGS–TWRI book 3, chap. A17. 1985. 38 p. 3-A18. Determination of stream reaeration coefficients by use of tracers, by F.A. Kilpatrick, R.E. Rathbun, Nobuhiro Yotsukura, G.W. Parker, and L.L. DeLong: USGS–TWRI book 3, chap. A18. 1989. 52 p. 3-A19. Levels at streamflow gaging stations, by E.J. Kennedy: USGS–TWRI book 3, chap. A19. 1990. 31 p. 3-A20. Simulation of soluble waste transport and buildup in surface waters using tracers, by F.A. Kilpatrick: USGS–TWRI book 3, chap. A20. 1993. 38 p. 3-A21 Stream-gaging cableways, by C. Russell Wagner: USGS–TWRI book 3, chap. A21. 1995. 56 p. Section B. Ground-Water Techniques 3-B1. Aquifer-test design, observation, and data analysis, by R.W. Stallman: USGS–TWRI book 3, chap. B1. 1971. 26 p. 3-B2. Introduction to ground-water hydraulics, a programed text for self-instruction, by G.D. Bennett: USGS–TWRI book 3, chap. B2. 1976. 172 p. 3-B3. Type curves for selected problems of flow to wells in confined aquifers, by J.E. Reed: USGS–TWRI book 3, chap. B3. 1980. 106 p. 3-B4. Regression modeling of ground-water flow, by R.L. Cooley and R.L. Naff: USGS–TWRI book 3, chap. B4. 1990. 232 p. 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, chap. B4. 1993. 8 p. 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, chap. B5. 1987. 15 p. 3-B6. The principle of superposition and its application in ground-water hydraulics, by T.E. Reilly, O.L. Franke, and G.D. Bennett: USGS–TWRI book 3, chap. B6. 1987. 28 p. 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, chap. B7. 1992. 190 p. 3-B8. System and boundary conceptualization in ground-water flow simulation, by T.E. Reilly: USGS–TWRI book 3, chap. B8. 2001. 29 p. Section C. Sedimentation and Erosion Techniques 3-C1. Fluvial sediment concepts, by H.P. Guy: USGS–TWRI book 3, chap. C1. 1970. 55 p. 3-C2. Field methods for measurement of fluvial sediment, by T.K. Edwards and G.D. Glysson: USGS–TWRI book 3, chap. C2. 1999. 89 p. 3-C3. Computation of fluvial-sediment discharge, by George Porterfield: USGS–TWRI book 3, chap. C3. 1972. 66 p. 50 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 PUBLICATIONS ON TECHNIQUES OF WATER-RESOURCES INVESTIGATIONS—Continued Book 4. Hydrologic Analysis and Interpretation Section A. Statistical Analysis 4-A1. Some statistical tools in hydrology, by H.C. Riggs: USGS–TWRI book 4, chap. A1. 1968. 39 p. 4-A2. Frequency curves, by H.C. Riggs: USGS–TWRI book 4, chap. A2. 1968. 15 p. Section B. Surface Water 4-B1. Low-flow investigations, by H.C. Riggs: USGS–TWRI book 4, chap. B1. 1972. 18 p. 4-B2. Storage analyses for water supply, by H.C. Riggs and C.H. Hardison: USGS–TWRI book 4, chap. B2. 1973. 20 p. 4-B3. Regional analyses of streamflow characteristics, by H.C. Riggs: USGS–TWRI book 4, chap. B3. 1973. 15 p. Section D. Interrelated Phases of the Hydrologic Cycle 4-D1. Computation of rate and volume of stream depletion by wells, by C.T. Jenkins: USGS–TWRI book 4, chap. D1. 1970. 17 p. Book 5. Laboratory Analysis Section A. Water Analysis 5-A1. Methods for determination of inorganic substances in water and fluvial sediments, by M.J. Fishman and L.C. Friedman, editors: USGS–TWRI book 5, chap. A1. 1989. 545 p. 5-A2. Determination of minor elements in water by emission spectroscopy, by P.R. Barnett and E.C. Mallory, Jr.: USGS– TWRI book 5, chap. A2. 1971. 31 p. 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, chap. A3. 1987. 80 p. 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, chap. A4. 1989. 363 p. 5-A5. Methods for determination of radioactive substances in water and fluvial sediments, by L.L. Thatcher, V.J. Janzer, and K.W. Edwards: USGS–TWRI book 5, chap. A5. 1977. 95 p. 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, chap. A6. 1982. 181 p. Section C. Sediment Analysis 5-C1. Laboratory theory and methods for sediment analysis, by H.P. Guy: USGS–TWRI book 5, chap. C1. 1969. 58 p. Book 6. Modeling Techniques Section A. Ground Water 6-A1. A modular three-dimensional finite-difference ground-water flow model, by M.G. McDonald and A.W. Harbaugh: USGS–TWRI book 6, chap. A1. 1988. 586 p. 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, chap. A2. 1991. 68 p. 6-A3. A modular finite-element model (MODFE) for areal and axisymmetric ground-water-flow problems, Part 1: Model Description and User’s Manual, by L.J. Torak: USGS–TWRI book 6, chap. A3. 1993. 136 p. 6-A4. A modular finite-element model (MODFE) for areal 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, chap. A4. 1992. 108 p. 6-A5. A modular finite-element model (MODFE) for areal and axisymmetric ground-water-flow problems, Part 3: Design philosophy and programming details, by L.J. Torak: USGS–TWRI book 6, chap. A5, 1993. 243 p. 6-A6. A coupled surface-water and ground-water flow model (MODBRANCH) for simulation of stream-aquifer interaction, by Eric D. Swain and Eliezer J. Wexler: USGS–TWRI book 6, chap. A5,1996. 125 p. PUBLICATIONS ON TECHNIQUES OF WATER-RESOURCES INVESTIGATIONS—Continued Book 7. Automated Data Processing and Computations 51 WATER RESOURCES DATA FOR PUERTO RICO AND THE U.S. VIRGIN ISLANDS, 2002 PUBLICATIONS ON TECHNIQUES OF WATER-RESOURCES INVESTIGATIONS—Continued Section C. Computer Programs 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, chap. C1. 1976. 116 p. 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, chap. C2. 1978. 90 p. 7-C3. A model for simulation of flow in singular and interconnected channels, by R.W. Schaffranek, R.A. Baltzer, and D.E. Goldberg: USGS–TWRI book 7, chap. C3. 1981. 110 p. Book 8. Instrumentation Section A. Instruments for Measurement of Water Level 8-A1. Methods of measuring water levels in deep wells, by M.S. Garber and F.C. Koopman: USGS–TWRI book 8, chap. A1. 1968. 23 p. 8-A2. Installation and service manual for U.S. Geological Survey manometers, by J.D. Craig: USGS–TWRI book 8, chap. A2. 1983. 57 p. Section B. Instruments for Measurement of Discharge 8-B2. Calibration and maintenance of vertical-axis type current meters, by G.F. Smoot and C.E. Novak: USGS–TWRI book 8, chap. B2. 1968. 15 p. Book 9. Handbooks for Water-Resources Investigations Section A. National Field Manual for the Collection of Water-Quality Data 9-A1. National Field Manual for the Collection of Water-Quality Data: Preparations for Water Sampling, by F.D. Wilde, D.B. Radtke, Jacob Gibs, and R.T. Iwatsubo: USGS–TWRI book 9, chap. A1. 1998. 47 p. 9-A2. National Field Manual for the Collection of Water-Quality Data: Selection of Equipment for Water Sampling, edited by F.D. Wilde, D.B. Radtke, Jacob Gibs, and R.T. Iwatsubo: USGS–TWRI book 9, chap. A2. 1998. 94 p. 9-A3. National Field Manual for the Collection of Water-Quality Data: Cleaning of Equipment for Water Sampling, edited by F.D. Wilde, D.B. Radtke, Jacob Gibs, and R.T. Iwatsubo: USGS–TWRI book 9, chap. A3. 1998. 75 p. 9-A4. National Field Manual for the Collection of Water-Quality Data: Collection of Water Samples, edited by F.D. Wilde, D.B. Radtke, Jacob Gibs, and R.T. Iwatsubo: USGS–TWRI book 9, chap. A4. 1999. 156 p. 9-A5. National Field Manual for the Collection of Water-Quality Data: Processing of Water Samples, edited by F.D. Wilde, D.B. Radtke, Jacob Gibs, and R.T. Iwatsubo: USGS–TWRI book 9, chap. A5. 1999, 149 p. 9-A6. National Field Manual for the Collection of Water-Quality Data: Field Measurements, edited by F.D. Wilde and D.B. Radtke: USGS–TWRI book 9, chap. A6. 1998. Variously paginated. 9-A7. National Field Manual for the Collection of Water-Quality Data: Biological Indicators, edited by D.N. Myers and F.D. Wilde: USGS–TWRI book 9, chap. A7. 1997 and 1999. Variously paginated. 9-A8. National Field Manual for the Collection of Water-Quality Data: Bottom-material samples, by D.B. Radtke: USGS– TWRI book 9, chap. A8. 1998. 48 p. 9-A9. National Field Manual for the Collection of Water-Quality Data: Safety in Field Activities, by S.L. Lane and R.G. Fay: USGS–TWRI book 9, chap. A9. 1998. 60 p. 52 THIS PAGE IS INTENTIONALLY BLANK THIS PAGE IS INTENTIONALLY BLANK 53 Surface and Quality-of-Water Records for Puerto Rico 54 THIS PAGE IS INTENTIONALLY BLANK 55 Figure 11. Río Guajataca basin. 56 RIO GUAJATACA BASIN 50010500 RIO GUAJATACA AT LARES, PR LOCATION.--Lat 18°18'01", long 66°52'24", Hydrologic Unit 21010001, at bridge on Highway 111, 0.1 mi (0.2 km) upstream from Quebrada Anón, and 0.4 mi (0.6 km) east of Lares. DRAINAGE AREA.--3.16 mi2 (8.18 km2). WATER-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.--Water-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. Record affected by domestic discharges entering upstream right bank of bridge. Discharge, cubic feet per second WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 10 e93 6.8 3.4 2.2 1.8 33 27 e9.4 e2.2 e5.8 e2.8 2 9.8 e22 15 2.7 1.2 1.7 6.5 23 e14 e2.2 e11 e17 3 18 e13 19 2.4 1.0 1.6 2.5 19 e26 e2.1 e8.8 e42 4 8.3 e12 8.8 2.4 1.1 1.6 20 17 e18 e3.0 e10 e125 5 7.8 e9.6 6.3 4.2 1.4 1.5 37 15 e12 e2.2 e8.4 e44 6 6.9 e9.8 5.4 3.7 1.7 2.2 9.2 14 e8.5 e2.7 e5.5 e15 7 7.8 e12 5.2 11 1.7 1.6 19 13 e7.3 e4.9 e3.3 e9.4 8 12 170 4.7 4.6 2.0 1.9 60 12 e6.6 e3.7 e2.4 e7.0 9 6.0 46 4.4 3.7 1.2 2.0 13 e54 e6.3 e7.2 e2.2 e5.9 10 e112 29 4.2 3.4 1.0 2.2 9.7 e48 e6.0 e5.4 e16 e22 11 e51 24 4.9 2.2 1.0 10 6.7 e23 e5.5 e3.9 e17 e23 12 e82 30 5.6 2.0 1.1 3.4 5.1 e15 e9.4 e8.4 e12 e6.9 13 e34 19 7.6 1.7 1.7 1.9 4.2 e13 e9.8 e12 e6.3 e5.8 14 e19 52 4.4 1.5 1.5 0.89 3.6 e11 e6.1 e6.3 e6.4 e6.1 15 e14 23 4.8 1.5 1.5 1.7 3.5 e21 e5.4 e7.8 e5.7 e6.4 16 e13 18 9.9 1.4 1.1 3.6 5.4 e82 e4.8 e4.3 e4.2 e14 17 e15 16 5.4 1.2 1.3 2.8 3.5 e42 e4.8 e2.7 e3.7 e5.7 18 e19 14 3.6 1.1 1.3 1.6 9.2 e25 e4.5 e1.9 e15 e59 19 e14 13 3.7 1.3 9.9 1.7 28 e20 e4.2 e2.1 e20 e8.3 20 e12 12 3.2 0.96 2.0 1.7 22 e17 e3.9 e1.8 e8.8 e28 21 e12 11 31 1.3 1.3 1.3 14 e15 e3.7 e1.8 e5.7 e6.4 22 e14 11 7.2 1.8 1.4 1.6 53 e13 e3.4 e1.6 e3.1 e4.1 23 e25 10 8.0 1.5 1.7 1.7 75 e12 e3.1 e2.7 e7.2 e3.5 24 e34 10 5.8 1.6 1.4 1.8 32 e11 e3.0 e1.6 e24 e3.4 25 e33 9.7 4.4 1.2 1.5 1.4 48 e10 e3.9 e1.6 e19 e3.2 26 e18 9.1 3.9 1.4 1.9 1.7 23 e10 e6.7 e1.3 e14 e3.7 27 e36 8.8 3.6 1.3 2.0 3.8 92 e9.3 e4.8 e1.3 e20 e3.4 28 e26 8.2 3.4 1.4 2.0 4.9 31 e9.1 e3.4 e4.8 e11 e3.0 29 e24 8.4 3.2 1.2 --- 1.8 75 e9.6 e3.0 e6.9 e5.3 e2.5 30 e20 7.5 3.1 1.3 --- 1.8 50 e11 e2.7 e3.0 e7.2 e2.6 31 e21 --- 3.0 1.6 --- 15 --- e10 --- e1.6 e3.5 --- TOTAL 734.6 731.1 209.5 71.96 50.1 84.19 794.1 631.0 210.2 115.0 292.5 489.1 MEAN 23.7 24.4 6.76 2.32 1.79 2.72 26.5 20.4 7.01 3.71 9.44 16.3 MAX 112 170 31 11 9.9 15 92 82 26 12 24 125 MIN 6.0 7.5 3.0 0.96 1.0 0.89 2.5 9.1 2.7 1.3 2.2 2.5 AC-FT 1460 1450 416 143 99 167 1580 1250 417 228 580 970 CFSM 7.50 7.71 2.14 0.73 0.57 0.86 8.38 6.44 2.22 1.17 2.99 5.16 IN. 8.65 8.61 2.47 0.85 0.59 0.99 9.35 7.43 2.47 1.35 3.44 5.76 STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1969 - 2002, BY WATER YEAR (WY) MEAN 18.0 10.6 4.20 3.21 2.89 2.77 5.14 11.7 8.17 4.92 7.11 15.1 MAX 33.7 25.8 8.32 8.91 7.21 10.6 26.5 25.4 23.4 9.85 11.8 45.2 (WY) 1991 2000 2000 1997 1996 1999 2002 1999 1999 1969 2001 1998 MIN 8.52 2.42 1.35 0.66 0.93 0.92 1.09 2.37 1.70 1.73 3.34 5.95 (WY) 1995 1998 1991 1991 1992 1994 1994 1997 1997 1997 1970 1993 SUMMARY STATISTICS FOR 2001 CALENDAR YEAR FOR 2002 WATER YEAR WATER YEARS 1969 - 2002 ANNUAL TOTAL 3678.26 4413.35 ANNUAL MEAN 10.1 12.1 7.82 HIGHEST ANNUAL MEAN 12.6 1999 LOWEST ANNUAL MEAN 4.13 1994 HIGHEST DAILY MEAN 170 Nov 8 170 Nov 8 505 Sep 22 1998 LOWEST DAILY MEAN 0.84 Apr 20 0.89 Mar 14 0.47 Jan 13 1991 ANNUAL SEVEN-DAY MINIMUM 0.94 Apr 14 1.3 Jan 15 0.51 Jan 9 1991 MAXIMUM PEAK FLOW 2840 Oct 10 5300 Oct 7 1990 MAXIMUM PEAK STAGE 17.25 Oct 10 21.30 Oct 7 1990 ANNUAL RUNOFF (AC-FT) 7300 8750 5660 ANNUAL RUNOFF (CFSM) 3.19 3.83 2.47 ANNUAL RUNOFF (INCHES) 43.30 51.95 33.61 10 PERCENT EXCEEDS 24 26 18 50 PERCENT EXCEEDS 4.8 6.1 3.6 90 PERCENT EXCEEDS 1.4 1.5 1.1 e Estimated 57 RIO GUAJATACA BASIN 50010500 RIO GUAJATACA AT LARES, PR--Continued O N D 2001 J F M A M J J A S 2002 0.1 0.2 0.5 1 2 5 10 10 20 50 100 100 200 500 1000 DISCHARGE, IN CUBIC FEET PER SECOND 58 RIO GUAJATACA BASIN 50010500 RIO GUAJATACA AT LARES, PR--Continued WATER-QUALITY RECORDS LOCATION.--Lat 18°18'01", long 66°52'24", at bridge on Highway 111 (km 32.9), 0.1 mi (0.2 km) upstream from Quebrada Anón and 0.4 mi (0.6 km) northeast of Lares Plaza. DRAINAGE AREA.--3.16 mi2 (8.18 km2). PERIOD OF RECORD.--Water years 1958-71, 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 TURBID- FECAL FECAL SPECIF. PH, ITY, DIS- COD, COLI- STREP- HARD- INSTAN- CONDUC- WATER, WAT UNF SOLVED HIGH FORM, TOCOCCI NESS, TANEOUS TANCE, UNFLTRD TEMPER- LAB, DIS- OXYGEN, LEVEL, M-FC KF WATER, CALCIUM DIS- WAT UNF FIELD, ATURE, HACH SOLVED PERCENT WATER, 0.7U MF MF, UNFLTRD WATER, DATE TIME CHARGE, US/CM STD WATER, 2100AN OXYGEN, OF SAT- UNFLTRD COL/ COL/ MG/L AS FLTRD, CFS 25 DEGC UNITS DEG C NTU MG/L URATION MG/L 100 ML 100 ML CACO3 MG/L (00061) (00095) (00400) (00010) (99872) (00300) (00301) (00340) (31625) (31673) (00900) (00915) DEC 11... 1130 4.2 232 6.9 22.3 2.8 8.2 98 <10 220 490 87 25.0 FEB 19... 1355 18 178 6.7 21.2 300 7.8 92 20 22000 75000 -- -- SEP 11... 1205 7.3 210 6.8 24.0 9.3 8.1 98 <10 2700 E1900 83 24.7 ANC, RESIDUE RESIDUE WAT UNF WATER, TOTAL MAGNES- POTAS- FIXED CHLOR- FLUOR- FLTRD, AT 105 IUM, SODIUM, SODIUM SIUM, END PT, SULFIDE SULFATE IDE, IDE, SILICA, SUM OF RESIDUE DEG. C, WATER, WATER, ADSORP- WATER, FIELD, WATER WATER, WATER, WATER, WATER, CONSTI- WATER, SUS- DATE FLTRD, FLTRD, TION FLTRD, MG/L AS UNFLTRD FLTRD, FLTRD, FLTRD, FLTRD, TUENTS FLTRD, PENDED, MG/L MG/L RATIO MG/L CACO3 MG/L MG/L MG/L MG/L MG/L MG/L TONS/D MG/L (00925) (00930) (00931) (00935) (00410) (00745) (00945) (00940) (00950) (00955) (70301) (70302) (00530) DEC 11... 5.96 11.3 .5 2.07 82 <1.0 4.3 10.9 <.1 33.6 142 1.60 <10 FEB 19... -- -- -- -- 49 -- -- -- -- -- -- -- 98 SEP 11... 5.16 10.1 .5 2.35 72 <.1 6.1 10.2 E.07 27.8 129 2.56 <10 NITRITE AMMONIA CHROM- + + BARIUM, BORON, IUM, COPPER, IRON, LEAD, NITRITE NITRATE AMMONIA ORG-N, PHOS- WATER, WATER, WATER, WATER, WATER, WATER, WATER, WATER WATER, WATER, PHORUS, ARSENIC UNFLTRD UNFLTRD CADMIUM UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD WATER, WATER RECOV- RECOV- WATER, RECOV- RECOV- RECOV- RECOV- DATE MG/L MG/L MG/L MG/L UNFLTRD UNFLTRD ERABLE, ERABLE, UNFLTRD ERABLE, ERABLE, ERABLE, ERABLE, AS N AS N AS N AS N MG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L (00615) (00630) (00610) (00625) (00665) (01002) (01007) (01022) (01027) (01034) (01042) (01045) (01051) DEC 11... .02 2.10 .05 <.20 E.06 E1 20.3 20 <.1 <.8 <10 70 <1 FEB 19... .01 1.80 .08 1.0 .17 -- -- -- -- -- -- -- -- SEP 11... <.01 1.10 .02 .20 .06 <2 23.8 E20 <.1 <.8 <10 210 <1 MANGAN- PHEN- ESE, MERCURY SILVER, ZINC, OLIC WATER, WATER, SELEN- WATER, WATER, COM- UNFLTRD UNFLTRD IUM, UNFLTRD UNFLTRD CYANIDE POUNDS, MBAS, RECOV- RECOV- WATER, RECOV- RECOV- WATER WATER, WATER, DATE ERABLE, ERABLE, UNFLTRD ERABLE, ERABLE, UNFLTRD UNFLTRD UNFLTRD UG/L UG/L UG/L UG/L UG/L MG/L UG/L MG/L (01055) (71900) (01147) (01077) (01092) (00720) (32730) (38260) DEC 11... 13.9 <.01 E1 <.3 <20 <.01 <16 <.05 FEB 19... -- -- -- -- -- -- -- -- SEP 11... 32.3 E.01 <2 <.3 <20 <.01 <16 <.05 < -- Less than E -- Estimated value 59 RIO GUAJATACA BASIN 50010800 LAGO GUAJATACA AT DAMSITE NEAR QUEBRADILLAS, PR LOCATION.--Lat 18°24'02", long 66°55'25", Hydrologic Unit 21010002, on right bank, in a concrete intake tower at Damsite, 5.2 mi (8.4 km) southeast from Quebradillas Plaza, 0.5 mi (0.8 km) northeast from Iglesia San Antonio de Padua and 2.8 mi (4.5 km) from Escuela Segunda Unidad Baldorioty de Castro. DRAINAGE AREA.--24.6 mi2 (63.71 km2) ELEVATION RECORDS PERIOD OF RECORD.--April 1995 to current year. GAGE.--Water-stage recorder. Datum of gage is mean sea level. REMARKS.--Lago Guajataca was completed in 1928. The dam is a semihydraulic earthfill structure about 123 ft (37 m) high, a top width of 31 ft (9.5 m) at crest elevation of 664 ft (202.5 m), a base width of 623 ft (190 m), a crest length of 1,036 ft (316 m) and has a maximum storage capacity of 49,200 acre-feet (60.6 hm3). The Guajataca Dam is owned by the Puerto Rico Electric Power Authority (PREPA) and provides water for the municipalities of Aguadilla, Isabela, Moca, Aguada, and Quebradillas although its primary purpose is for agricultural irrigation for the flatlands of the area. Gage-height and precipitation satellite telemetry at station. New capacity table based on U.S. Geological Survey Water-Resources Investigations Report 00-4044, January 1999. EXTREMES OBSERVED FOR PERIOD OF RECORD.--Maximum elevation 648.3 ft (197.60 m), September 23, 1998; minimum elevation, 608.07 ft (185.34 m) May 17, 1998. EXTREMES OBSERVED FOR CURRENT YEAR.--Maximum elevation, 646.29 ft (196.99 m), November 9; minimum elevation, 631.15 ft (192.37 m), March 31. Capacity Table (based on data from U.S. Geological Survey Water-Resources Investigations Report 00-4044, Puerto Rico, 1999) Elevation, in feet Contents, in acre-feet Elevation, in feet Contents, in acre-feet 557 0 616 13,393 577 916 636 26,332 597 5,253 646 34,277 Elevation above NGVD 1929, feet WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 DAILY OBSERVATION AT 2400 HOURS DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 640.77 643.01 A 641.31 638.55 635.00 632.49 644.54 639.45 637.45 635.97 639.99 2 640.74 643.25 A 641.23 638.42 634.85 633.13 644.32 639.54 637.32 635.91 639.73 3 640.72 643.07 A 641.13 638.28 634.72 633.17 643.69 639.93 637.29 635.79 641.39 4 640.69 643.19 A 641.02 638.16 634.57 633.37 642.97 640.04 637.22 635.70 643.36 5 640.59 642.83 642.28 641.00 638.03 634.41 634.81 642.21 640.03 637.09 635.58 644.06 6 640.50 642.71 642.14 640.94 637.91 634.26 635.38 641.41 640.02 637.15 635.45 643.59 7 640.42 642.78 642.05 641.22 637.78 634.11 635.73 640.81 639.93 637.10 635.31 642.88 8 640.41 645.72 641.96 641.30 637.66 634.01 637.00 640.44 639.84 637.22 635.18 642.08 9 640.37 646.26 641.86 641.24 637.53 633.93 637.36 640.83 639.92 637.23 635.42 641.43 10 640.73 646.05 641.77 641.15 637.41 633.82 637.48 641.36 639.87 637.13 636.44 640.82 11 641.42 645.98 641.67 641.05 637.27 633.74 637.52 641.22 639.78 637.02 636.66 640.39 12 642.18 645.90 641.74 640.95 637.12 633.68 637.50 640.66 639.70 637.32 636.67 640.44 13 642.50 645.50 641.82 640.87 636.99 633.57 637.47 640.52 639.60 637.33 636.62 640.52 14 642.35 645.27 641.74 640.76 636.85 633.43 637.40 640.51 639.55 637.31 636.59 640.53 15 641.96 644.83 641.62 640.65 636.71 633.28 637.35 640.86 639.43 637.26 636.55 640.73 16 641.59 644.09 641.56 640.54 636.58 633.12 637.30 641.99 639.31 637.16 636.47 640.60 17 641.53 643.37 641.65 640.42 636.43 633.00 637.21 641.82 639.20 637.10 636.38 640.82 18 641.54 642.75 641.59 640.30 636.30 632.85 637.17 641.14 639.08 637.27 636.45 641.61 19 641.49 642.61 641.50 640.18 636.36 632.71 637.39 640.53 638.97 637.19 636.87 641.64 20 641.47 A 641.41 640.06 636.23 632.54 637.70 640.25 638.83 637.07 636.91 641.27 21 641.40 642.36 642.58 639.93 636.10 632.40 638.01 640.22 638.70 636.96 636.84 640.70 22 641.33 642.28 642.82 639.81 635.95 632.26 638.45 640.17 638.57 636.86 636.78 640.08 23 641.96 642.27 642.65 639.69 635.81 632.13 639.03 640.11 638.44 636.75 637.11 639.88 24 642.37 642.15 642.13 639.59 635.67 631.98 639.49 640.03 638.32 636.63 637.99 639.74 25 642.48 642.08 641.78 639.46 635.54 631.82 640.14 639.96 638.20 636.49 638.26 639.50 26 642.46 642.01 641.76 639.34 635.40 631.66 640.50 639.89 638.10 636.35 638.51 639.45 27 642.60 A 641.70 639.21 635.26 631.67 642.35 639.80 638.00 636.22 639.03 639.39 28 642.56 A 641.64 639.09 635.12 631.55 642.98 639.73 637.87 636.16 639.12 639.44 29 642.67 A 641.56 638.96 --- 631.40 643.70 639.66 637.73 636.04 639.60 639.37 30 642.54 A 641.48 638.82 --- 631.26 644.18 639.57 637.59 635.91 639.99 639.29 31 642.53 A 641.40 638.69 --- 631.31 --- 639.54 --- 635.77 640.09 --- MAX 642.67 --- --- 641.31 638.55 635.00 644.18 644.54 640.04 637.45 640.09 644.06 MIN 640.37 --- --- 638.69 635.12 631.26 632.49 639.54 637.59 635.77 635.18 639.29 A No gage-height record 60 RIO GUAJATACA BASIN 50010800 LAGO GUAJATACA AT DAMSITE NEAR QUEBRADILLAS, PR--Continued O N D 2001 J F M A M J J A S 2002 630 632 634 636 638 640 642 644 646 648 ELEVATION, IN FEET Gap indicates missing record 61 RIO GUAJATACA BASIN 50011000 CANAL PRINCIPAL DE DIVERSIONES AT LAGO DE GUAJATACA, PR WATER-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.--Water years 1958-64, 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 TURBID- FECAL FECAL SPECIF. PH, ITY, DIS- COD, COLI- STREP- HARD- INSTAN- CONDUC- WATER, WAT UNF SOLVED HIGH FORM, TOCOCCI NESS, TANEOUS TANCE, UNFLTRD TEMPER- LAB, DIS- OXYGEN, LEVEL, M-FC KF WATER, CALCIUM DIS- WAT UNF FIELD, ATURE, HACH SOLVED PERCENT WATER, 0.7U MF MF, UNFLTRD WATER, DATE TIME CHARGE, US/CM STD WATER, 2100AN OXYGEN, OF SAT- UNFLTRD COL/ COL/ MG/L AS FLTRD, CFS 25 DEGC UNITS DEG C NTU MG/L URATION MG/L 100 ML 100 ML CACO3 MG/L (00061) (00095) (00400) (00010) (99872) (00300) (00301) (00340) (31625) (31673) (00900) (00915) DEC 17... 1630 108 320 7.2 24.9 1.9 .7 9 <10 83 E14 150 52.7 FEB 19... 1600 108 307 7.6 25.2 2.8 1.3 17 <10 E2 E2 -- -- SEP 13... 0800 -- 290 6.6 25.5 5.2 2.3 28 <10 E29 E16 140 51.6 ANC, RESIDUE RESIDUE WAT UNF WATER, TOTAL MAGNES- POTAS- FIXED CHLOR- FLUOR- FLTRD, AT 105 IUM, SODIUM, SODIUM SIUM, END PT, SULFIDE SULFATE IDE, IDE, SILICA, SUM OF RESIDUE DEG. C, WATER, WATER, ADSORP- WATER, FIELD, WATER WATER, WATER, WATER, WATER, CONSTI- WATER, SUS- DATE FLTRD, FLTRD, TION FLTRD, MG/L AS UNFLTRD FLTRD, FLTRD, FLTRD, FLTRD, TUENTS FLTRD, PENDED, MG/L MG/L RATIO MG/L CACO3 MG/L MG/L MG/L MG/L MG/L MG/L TONS/D MG/L (00925) (00930) (00931) (00935) (00410) (00745) (00945) (00940) (00950) (00955) (70301) (70302) (00530) DEC 17... 3.37 5.31 .2 1.66 139 <1.0 7.4 6.84 .2 7.4 168 31.7 <10 FEB 19... -- -- -- -- 139 -- -- -- -- -- -- -- <10 SEP 13... 3.23 4.63 .2 1.94 120 <.1 7.7 6.59 E.10 6.7 154 -- <10 NITRITE AMMONIA CHROM- + + BARIUM, BORON, IUM, COPPER, IRON, LEAD, NITRITE NITRATE AMMONIA ORG-N, PHOS- WATER, WATER, WATER, WATER, WATER, WATER, WATER, WATER WATER, WATER, PHORUS, ARSENIC UNFLTRD UNFLTRD CADMIUM UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD WATER, WATER RECOV- RECOV- WATER, RECOV- RECOV- RECOV- RECOV- DATE MG/L MG/L MG/L MG/L UNFLTRD UNFLTRD ERABLE, ERABLE, UNFLTRD ERABLE, ERABLE, ERABLE, ERABLE, AS N AS N AS N AS N MG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L (00615) (00630) (00610) (00625) (00665) (01002) (01007) (01022) (01027) (01034) (01042) (01045) (01051) DEC 17... <.01 .270 .21 .20 <.02 M 19.6 E10 <.1 <.8 <10 50 <1 FEB 19... <.01 <.020 .02 .30 .04 -- -- -- -- -- -- -- -- SEP 13... <.01 .320 .02 .30 <.02 <2 15.7 M <.1 <.8 <10 80 <1 MANGAN- PHEN- ESE, MERCURY SILVER, ZINC, OLIC WATER, WATER, SELEN- WATER, WATER, COM- UNFLTRD UNFLTRD IUM, UNFLTRD UNFLTRD CYANIDE POUNDS, MBAS, RECOV- RECOV- WATER, RECOV- RECOV- WATER WATER, WATER, DATE ERABLE, ERABLE, UNFLTRD ERABLE, ERABLE, UNFLTRD UNFLTRD UNFLTRD UG/L UG/L UG/L UG/L UG/L MG/L UG/L MG/L (01055) (71900) (01147) (01077) (01092) (00720) (32730) (38260) DEC 17... 59.7 <.01 <2 <.3 <20 <.01 -- <.05 FEB 19... -- -- -- -- -- -- -- -- SEP 13... 47.9 <.01 <2 <.3 <20 <.01 <16 <.05 < -- Less than E -- Estimated value M -- Presence verified, not quantified 62 RIO GUAJATACA BASIN 50011400 RIO GUAJATACA ABOVE MOUTH NEAR QUEBRADILLAS, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°28'31", long 66°57'46", Hydrologic Unit 21010002, on left bank at ford 1.7 mi (2.7 km) upstream from bridge on highway 2, 1.6 mi (2.6 km) 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 2001 TO SEPTEMBER 2002 TURBID- FECAL FECAL SPECIF. PH, ITY, DIS- COD, COLI- STREP- HARD- INSTAN- CONDUC- WATER, WAT UNF SOLVED HIGH FORM, TOCOCCI NESS, TANEOUS TANCE, UNFLTRD TEMPER- LAB, DIS- OXYGEN, LEVEL, M-FC KF WATER, CALCIUM DIS- WAT UNF FIELD, ATURE, HACH SOLVED PERCENT WATER, 0.7U MF MF, UNFLTRD WATER, DATE TIME CHARGE, US/CM STD WATER, 2100AN OXYGEN, OF SAT- UNFLTRD COL/ COL/ MG/L AS FLTRD, CFS 25 DEGC UNITS DEG C NTU MG/L URATION MG/L 100 ML 100 ML CACO3 MG/L (00061) (00095) (00400) (00010) (99872) (00300) (00301) (00340) (31625) (31673) (00900) (00915) DEC 19... 1100 25 445 7.6 24.2 7.6 7.3 87 <10 600 E1080 200 71.1 MAR 11... 1030 20 509 7.5 23.5 1.6 6.5 77 <10 108 96 -- -- SEP 13... 1205 30 374 6.9 26.2 4.2 7.3 91 <10 E164 E164 180 64.8 ANC, RESIDUE RESIDUE WAT UNF WATER, TOTAL MAGNES- POTAS- FIXED CHLOR- FLUOR- FLTRD, AT 105 IUM, SODIUM, SODIUM SIUM, END PT, SULFIDE SULFATE IDE, IDE, SILICA, SUM OF RESIDUE DEG. C, WATER, WATER, ADSORP- WATER, FIELD, WATER WATER, WATER, WATER, WATER, CONSTI- WATER, SUS- DATE FLTRD, FLTRD, TION FLTRD, MG/L AS UNFLTRD FLTRD, FLTRD, FLTRD, FLTRD, TUENTS FLTRD, PENDED, MG/L MG/L RATIO MG/L CACO3 MG/L MG/L MG/L MG/L MG/L MG/L TONS/D MG/L (00925) (00930) (00931) (00935) (00410) (00745) (00945) (00940) (00950) (00955) (70301) (70302) (00530) DEC 19... 5.13 10.9 .3 1.44 189 <1.0 7.2 18.7 <.1 6.7 234 16.0 12 MAR 11... -- -- -- -- 207 -- -- -- -- -- -- -- <10 SEP 13... 5.10 8.40 .3 1.55 160 <.1 7.6 12.9 E.09 7.3 204 16.4 <10 NITRITE AMMONIA CHROM- + + BARIUM, BORON, IUM, COPPER, IRON, LEAD, NITRITE NITRATE AMMONIA ORG-N, PHOS- WATER, WATER, WATER, WATER, WATER, WATER, WATER, WATER WATER, WATER, PHORUS, ARSENIC UNFLTRD UNFLTRD CADMIUM UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD WATER, WATER RECOV- RECOV- WATER, RECOV- RECOV- RECOV- RECOV- DATE MG/L MG/L MG/L MG/L UNFLTRD UNFLTRD ERABLE, ERABLE, UNFLTRD ERABLE, -ABLE, ERABLE, ERABLE, AS N AS N AS N AS N MG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L (00615) (00630) (00610) (00625) (00665) (01002) (01007) (01022) (01027) (01034) (01042) (01045) (01051) DEC 19... <.01 1.40 .03 .20 <.02 E1 11.4 30 E.1 E.7 <10 120 <1 MAR 11... <.01 2.40 <.01 <.20 <.02 -- -- -- -- -- -- -- -- SEP 13... <.01 1.80 .02 .20 <.02 <2 13.5 E10 <.1 E.4 <10 60 <1 MANGAN- PHEN- ESE, MERCURY SILVER, ZINC, OLIC WATER, WATER, SELEN- WATER, WATER, COM- UNFLTRD UNFLTRD IUM, UNFLTRD UNFLTRD CYANIDE POUNDS, MBAS, RECOV- RECOV- WATER, RECOV- RECOV- WATER WATER, WATER, DATE ERABLE, ERABLE, UNFLTRD ERABLE, ERABLE, UNFLTRD UNFLTRD UNFLTRD UG/L UG/L UG/L UG/L UG/L MG/L UG/L MG/L (01055) (71900) (01147) (01077) (01092) (00720) (32730) (38260) DEC 19... 17.6 <.01 <2 <.3 <20 <.01 -- <.05 MAR 11... -- -- -- -- -- -- -- -- SEP 13... 22.8 <.01 <2 <.3 E20 <.01 <16 <.05 < -- Less than E -- Estimated value 63 Figure 12. Río Camuy basin. 64 RIO CAMUY BASIN 50014800 RIO CAMUY NEAR BAYANEY, PR LOCATION.--Lat 18°23'48", long 66°49'04", Hydrologic 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 mouth. DRAINAGE AREA.--Indeterminate. 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 2001 TO SEPTEMBER 2002 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 77 125 77 78 45 37 168 462 89 47 68 172 2 72 227 128 75 44 37 222 336 114 47 102 252 3 75 184 188 73 44 36 85 243 186 47 86 564 4 78 198 151 71 44 36 58 201 137 53 94 391 5 67 184 141 73 43 35 493 172 103 49 83 252 6 65 132 94 94 42 34 370 154 85 50 66 182 7 62 155 87 85 43 33 268 139 77 62 54 119 8 65 3580 82 102 42 35 791 127 73 55 48 98 9 78 1050 78 76 42 41 280 376 70 74 48 107 10 e682 491 76 71 42 39 169 347 70 63 129 158 11 e374 338 74 66 41 50 123 193 67 57 135 212 12 e510 267 81 64 41 65 100 146 90 82 103 155 13 e307 221 88 63 41 46 86 130 91 103 70 95 14 e177 253 78 62 40 34 77 120 71 71 71 81 15 e121 230 74 60 40 30 73 175 66 80 68 98 16 e107 173 89 59 40 31 74 538 63 61 59 132 17 e95 152 199 58 39 38 81 308 62 51 55 97 18 e93 139 118 56 39 29 72 202 61 48 118 280 19 98 130 94 56 48 30 247 151 60 46 152 210 20 97 121 84 54 58 28 245 132 58 45 84 181 21 79 114 660 52 43 28 242 121 57 45 68 160 22 74 107 334 51 40 27 248 112 55 44 54 104 23 206 103 252 50 39 26 379 106 53 50 96 90 24 315 102 234 51 40 26 427 100 52 46 192 85 25 162 96 148 50 39 27 471 95 57 45 164 86 26 106 92 120 49 39 29 326 93 72 44 132 77 27 158 88 106 48 39 32 708 90 61 43 181 72 28 427 86 96 48 38 53 511 90 54 62 107 68 29 255 90 89 49 --- 50 544 91 51 76 139 66 30 206 83 84 48 --- 34 722 100 49 52 129 92 31 155 --- 80 46 --- 35 --- 93 --- 45 147 --- TOTAL 5443 9311 4284 1938 1175 1111 8660 5743 2254 1743 3102 4736 MEAN 176 310 138 62.5 42.0 35.8 289 185 75.1 56.2 100 158 MAX 682 3580 660 102 58 65 791 538 186 103 192 564 MIN 62 83 74 46 38 26 58 90 49 43 48 66 STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1984 - 2002, BY WATER YEAR (WY) MEAN 201 138 76.8 59.0 50.3 47.8 93.2 167 115 74.5 97.1 188 MAX 427 310 179 163 96.4 93.7 289 624 322 109 187 726 (WY) 1986 2002 2000 1997 1996 1999 2002 1986 1999 1989 1998 1998 MIN 81.6 53.4 30.2 33.1 29.1 23.7 28.0 43.2 42.7 38.8 47.9 61.8 (WY) 1988 1998 2001 1991 1998 1994 1994 1989 1997 1994 1993 1997 SUMMARY STATISTICS FOR 2001 CALENDAR YEAR FOR 2002 WATER YEAR WATER YEARS 1984 - 2002 ANNUAL TOTAL 38522 49500 ANNUAL MEAN 106 136 109 HIGHEST ANNUAL MEAN 179 1986 LOWEST ANNUAL MEAN 61.5 1994 HIGHEST DAILY MEAN 3580 Nov 8 3580 Nov 8 9010 Sep 22 1998 LOWEST DAILY MEAN 24 Mar 18 26 Mar 23 16 Mar 18 1994 ANNUAL SEVEN-DAY MINIMUM 24 Mar 16 27 Mar 20 17 Mar 16 1994 MAXIMUM PEAK FLOW 7430 Nov 8 11600 Sep 22 1998 MAXIMUM PEAK STAGE 18.52 Nov 8 21.69 Sep 22 1998 INSTANTANEOUS LOW FLOW 24 Mar 25 15 Mar 22 1994 10 PERCENT EXCEEDS 190 254 212 50 PERCENT EXCEEDS 67 83 68 90 PERCENT EXCEEDS 29 40 33 e Estimated 65 RIO CAMUY BASIN 50014800 RIO CAMUY NEAR BAYANEY, PR--Continued O N D 2001 J F M A M J J A S 2002 10 20 50 100 100 200 500 1000 1000 2000 5000 10,000 DISCHARGE, IN CUBIC FEET PER SECOND 66 THIS PAGE IS INTENTIONALLY BLANK 67 Figure 13. Río Grande de Arecibo basin. 68 RIO GRANDE DE ARECIBO 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 Río Vacas, 1.7 mi (2.7 km) upstream from Río Garzas, and 2.2 mi (3.5 km) southwest of Adjuntas. DRAINAGE AREA.--15.6 mi2 (40.4 km2). ELEVATION RECORDS PERIOD OF RECORD.--January 1988 to May 1989, March 1993 to current year. GAGE.--Water-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 (724.45 m), May 25 to July 13, 1988, at datum 2,338.08 ft (712.65 m), July 14, 1988, to May 25, 1989, at datum 2,337.82 ft (712.56 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 Puerto Rico Electric Power Authorithy. Gage-height and precipitation satellite telemetry at station. New capacity table based on U.S. Geological Survey Water-Resources Investigations Report 99-4143, September 1996. EXTREMES OBSERVED FOR PERIOD OF RECORD.--Maximum elevation 2,418.28 ft (737.09 m), September 22, 1998; minimum elevation, 2,364.79 ft (720.79 m), August 23, 1988. EXTREMES OBSERVED FOR CURRENT YEAR.--Maximum elevation, 2,415.98 ft (736.39 m), September 24; minimum elevation, 2,411.89 ft (735.14 m), December 28. Capacity Table (based on data from U.S. Geological Survey Water-Resources Investigations Report 99-4143, 1996) Elevation, in feet Contents, in acre-feet Elevation, in feet Contents, in acre-feet 2,317 0 2,376 1,419 2,336 243 2,399 2,700 2,359 794 2,415 4,143 Elevation above NGVD 1929, feet WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 DAILY OBSERVATION AT 2400 HOURS DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 2414.03 2414.97 2414.95 A A A 2413.30 A A 2414.92 2414.90 2415.00 2 2414.27 2414.96 2414.94 A A A 2413.39 2415.02 A 2414.84 2414.81 2415.04 3 2414.51 2414.98 2415.02 A A A 2413.46 2415.01 A 2414.73 2414.90 2415.11 4 2414.71 2415.02 2414.98 A A A 2413.41 2415.00 A 2414.81 2414.92 2415.03 5 2414.82 2414.98 2414.97 A A A 2414.68 2414.94 A 2414.86 2415.00 2414.94 6 2414.84 2414.98 2414.96 A A A 2414.90 2414.98 A 2414.93 2414.94 2415.00 7 2414.88 2414.72 2414.67 A A A 2414.93 2414.91 A 2414.88 2414.99 2415.00 8 2414.85 2414.46 2414.85 A A A 2414.31 2415.00 A 2414.91 2414.95 2415.00 9 2414.94 2414.85 2414.99 A A A A 2414.98 A 2414.86 2414.95 2414.98 10 2415.03 2414.97 2412.56 A A A A 2415.02 A 2414.91 2414.95 A 11 2414.95 2415.01 2414.57 A A A A 2414.95 A 2414.85 2414.96 A 12 2414.94 2414.97 2414.83 A A A A 2414.94 A 2414.69 2414.68 A 13 2414.93 2414.98 2415.02 A A A A 2414.96 A 2414.79 2414.90 A 14 2414.94 2415.22 2414.96 A A A A 2414.94 A 2415.04 2414.95 A 15 2414.98 2415.22 2415.09 A A A A 2414.96 A 2414.94 2414.94 A 16 2414.97 2415.19 2415.17 A A A A 2414.98 A 2414.92 2414.89 A 17 2414.90 2415.17 2415.23 A A A A 2414.29 A 2414.87 2414.90 A 18 2414.97 2415.16 2415.16 A A A A 2413.87 A 2414.84 2415.01 A 19 2414.95 2415.16 2415.17 A A A A 2413.52 A 2414.85 2414.96 A 20 2414.96 2415.16 2415.16 A A 2412.25 A 2413.73 A 2414.91 2414.96 A 21 2414.96 2415.02 2415.14 A A 2412.53 A 2413.84 2414.74 2414.92 2415.02 A 22 2414.94 2415.09 2415.15 A A 2412.40 A 2414.00 2414.84 2414.92 2414.96 A 23 2414.98 2415.10 2415.15 A A 2412.48 A 2414.15 2414.88 2414.92 2414.95 A 24 2414.98 2415.08 2415.14 A A 2412.55 A 2414.20 2414.88 2414.77 2415.01 2415.94 25 2415.01 2415.07 2415.13 A A 2412.48 A 2414.35 2414.89 2414.88 2415.03 2415.93 26 2414.82 2415.02 2414.86 A A 2412.52 A 2414.51 2414.89 2414.92 2415.13 2415.89 27 2414.87 2415.02 2415.03 A A 2412.41 A 2414.67 2414.91 2414.80 2414.99 2415.84 28 2414.99 2415.00 2414.67 A A 2412.43 A 2414.46 2414.84 2414.91 2415.04 2415.10 29 A 2415.02 2414.82 A --- 2412.51 A A 2414.92 2414.88 2414.99 2415.34 30 2415.01 2414.97 2414.97 A --- 2412.63 A A 2414.92 2415.05 2415.04 2415.55 31 2414.95 --- 2414.17 A --- 2413.13 --- A --- 2414.93 2415.06 --- MAX --- 2415.22 2415.23 --- --- --- --- --- --- 2415.05 2415.13 --- MIN --- 2414.46 2412.56 --- --- --- --- --- --- 2414.69 2414.68 --- A No gage-height record 69 RIO GRANDE DE ARECIBO BASIN 50020100 LAGO GARZAS NEAR ADJUNTAS, PR--Continued O N D 2001 J F M A M J J A S 2002 2412 2412.5 2413 2413.5 2414 2414.5 2415 2415.5 2416 ELEVATION, IN FEET Gap indicates missing record 70 RIO GRANDE DE ARECIBO BASIN 50020500 RIO GRANDE DE ARECIBO NEAR ADJUNTAS, PR LOCATION.--Lat 18°10'54", long 66°44'12", Hydrologic Unit 21010002, at Highway 135 bridge junction with Highway 10, 1.4 mi (2.2 km) south from Lago Adjuntas and 1.5 mi (2.4 km) northwest of Adjuntas Plaza. DRAINAGE AREA.--12.7 mi2 (32.9 km2), this does not include 6.0 mi2 (15.6 km2) above Lago Garzas. WATER-DISCHARGE RECORDS PERIOD OF RECORD.--November 1946 to April 1950 (operated by Puerto Rico Water Resources Authority), March 2000 to current year. GAGE.--Water-stage recorder. Elevation of gage is 1,443 ft (440 m), from topographic map. REMARKS.--Records poor. Flow affected by Lago Garzas, 2.63 mi (4.23 km) and sewage treatment plant 1.1 mi (1.77 km) upstream from gage. Gage-height and precipitation satellite telemetry at station. Discharge, cubic feet per second WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 26 34 26 22 18 12 19 49 17 19 15 65 2 25 73 14 26 14 11 14 75 22 17 13 152 3 25 40 91 28 16 11 12 52 51 12 11 287 4 23 59 43 25 19 11 11 56 146 9.9 13 154 5 27 47 31 24 14 11 192 43 72 11 54 47 6 33 65 28 25 15 10 83 45 53 21 29 29 7 37 44 24 23 16 10 42 45 43 22 31 34 8 31 287 16 26 14 11 40 35 36 15 36 31 9 33 101 19 26 15 11 32 40 34 16 24 28 10 155 55 20 20 15 9.9 24 59 31 12 23 40 11 57 70 97 24 14 49 19 42 29 14 27 37 12 35 61 48 20 14 17 18 31 30 10 21 32 13 33 63 24 24 14 11 13 29 28 8.7 19 212 14 30 100 22 26 14 11 13 30 22 15 34 68 15 49 65 19 23 13 11 17 26 18 40 21 159 16 34 53 84 22 13 13 19 30 20 19 32 131 17 29 43 173 23 13 13 53 27 23 15 13 61 18 29 40 e78 16 14 11 23 16 29 11 e63 55 19 32 38 54 16 35 11 18 15 23 9.4 32 38 20 29 39 41 15 16 10 230 15 27 9.6 21 34 21 30 34 65 16 13 10 149 15 13 14 30 34 22 157 25 39 19 12 9.5 54 14 12 21 29 34 23 114 31 41 22 12 8.9 302 14 14 18 18 32 24 47 38 36 22 11 8.7 245 14 18 15 17 e33 25 39 32 32 23 11 8.7 344 13 17 8.6 38 41 26 36 31 27 23 14 8.9 317 14 24 11 91 32 27 33 29 20 22 13 8.8 245 14 19 13 64 29 28 65 29 20 21 12 9.1 161 15 19 17 98 21 29 75 44 18 16 --- 59 82 18 14 14 45 12 30 93 31 18 16 --- 17 62 32 19 45 103 11 31 45 --- 18 16 --- 38 --- 25 --- 41 87 --- TOTAL 1506 1701 1286 670 414 451.5 2853 948 923 524.2 1152 1973 MEAN 48.6 56.7 41.5 21.6 14.8 14.6 95.1 30.6 30.8 16.9 37.2 65.8 MAX 157 287 173 28 35 59 344 75 146 45 103 287 MIN 23 25 14 15 11 8.7 11 13 12 8.6 11 11 AC-FT 2990 3370 2550 1330 821 896 5660 1880 1830 1040 2280 3910 CFSM 2.60 3.03 2.22 1.16 0.79 0.78 5.09 1.64 1.65 0.90 1.99 3.52 IN. 3.00 3.38 2.56 1.33 0.82 0.90 5.68 1.89 1.84 1.04 2.29 3.92 STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1947 - 2002, BY WATER YEAR (WY) MEAN 77.4 52.9 36.7 22.1 24.3 15.5 27.9 36.8 27.1 27.5 48.7 84.8 MAX 119 75.2 41.5 29.6 56.9 21.6 95.1 72.2 36.0 49.3 94.5 129 (WY) 2001 2001 2002 1949 1950 1949 2002 2001 2000 1949 2000 2000 MIN 48.6 27.3 30.8 19.7 14.8 10.2 10.4 12.2 14.7 16.9 24.1 55.8 (WY) 2002 1950 1947 1948 2002 2001 1948 1948 2001 2002 2001 1947 SUMMARY STATISTICS FOR 2001 CALENDAR YEAR FOR 2002 WATER YEAR WATER YEARS 1947 - 2002 ANNUAL TOTAL 12541.5 14401.7 ANNUAL MEAN 34.4 39.5 40.8 HIGHEST ANNUAL MEAN 41.4 1948 LOWEST ANNUAL MEAN 39.5 2002 HIGHEST DAILY MEAN 1240 May 6 344 Apr 25 1510 Aug 23 2000 LOWEST DAILY MEAN 6.8 Mar 31 8.6 Jul 25 6.8 Mar 31 2001 ANNUAL SEVEN-DAY MINIMUM 7.1 Mar 27 8.9 Mar 22 7.1 Mar 27 2001 MAXIMUM PEAK FLOW 2120 Apr 23 12000 May 6 2001 MAXIMUM PEAK STAGE 9.22 Apr 23 15.49 May 6 2001 ANNUAL RUNOFF (AC-FT) 24880 28570 29550 ANNUAL RUNOFF (CFSM) 2.71 2.11 2.18 ANNUAL RUNOFF (INCHES) 36.74 28.65 29.64 10 PERCENT EXCEEDS 65 74 77 50 PERCENT EXCEEDS 19 25 23 90 PERCENT EXCEEDS 9.8 11 12 e Estimated 71 RIO GRANDE DE ARECIBO BASIN 50020500 RIO GRANDE DE ARECIBO NEAR ADJUNTAS, PR--Continued O N D 2001 J F M A M J J A S 2002 1 2 5 10 10 20 50 100 100 200 500 1000 DISCHARGE, IN CUBIC FEET PER SECOND 72 RIO GRANDE DE ARECIBO BASIN 50020500 RIO GRANDE DE ARECIBO NEAR ADJUNTAS, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1969-74, 1979 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: October 2000 to current year. INSTRUMENTATION.--USDH-48 and automatic sediment samplers since 2000. REMARKS.-- Sediment samples were collected by a local observer on a weekly basis. During high flow events sediment samples were collected with automatic sediment sampler. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATION: Maximum daily mean, 1,390 mg/L April 23, 2002; Minimum daily mean, 1 mg/L several days during 2001 and 2002. SEDIMENT LOADS: Maximum daily mean, 14,400 tons (13,064 tonnes) May 6, 2001; Minimum daily mean, 0.03 ton (0.03 tonne) June 1, 2, 2001. EXTREMES FOR CURRENT YEAR 2002.-- SEDIMENT CONCENTRATION: Maximum daily mean, 1,390 mg/L April 23, 2002; Minimum daily mean, 1 mg/L several days. SEDIMENT LOADS: Maximum daily mean, 3,780 tons (3,429 tonnes) April 23, 2002; Minimum daily mean, 0.04 ton (0.04 tonne) December 8, 2002. WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 TURBID- FECAL FECAL SPECIF. PH, ITY, DIS- COD, COLI- STREP- HARD- INSTAN- CONDUC- WATER, WAT UNF SOLVED HIGH FORM, TOCOCCI NESS, TANEOUS TANCE, UNFLTRD TEMPER- LAB, DIS- OXYGEN, LEVEL, M-FC KF WATER, CALCIUM DIS- WAT UNF FIELD, ATURE, HACH SOLVED PERCENT WATER, 0.7U MF MF, UNFLTRD WATER, DATE TIME CHARGE, US/CM STD WATER, 2100AN OXYGEN, OF SAT- UNFLTRD COL/ COL/ MG/L AS FLTRD, CFS 25 DEGC UNITS DEG C NTU MG/L URATION MG/L 100 ML 100 ML CACO3 MG/L (00061) (00095) (00400) (00010) (99872) (00300) (00301) (00340) (31625) (31673) (00900) (00915) DEC 17... 1255 40 245 7.2 23.4 6.0 8.3 104 <10 3600 480 87 22.7 MAR 12... 0800 15 277 7.4 19.1 1.9 7.9 91 <10 E1180 3200 -- -- SEP 10... 0905 -- 186 6.8 24.0 26 8.0 99 <10 330 310 100 27.6 ANC, RESIDUE RESIDUE WAT UNF WATER, TOTAL MAGNES- POTAS- FIXED CHLOR- FLUOR- FLTRD, AT 105 IUM, SODIUM, SODIUM SIUM, END PT, SULFIDE SULFATE IDE, IDE, SILICA, SUM OF RESIDUE DEG. C, WATER, WATER, ADSORP- WATER, FIELD, WATER WATER, WATER, WATER, WATER, CONSTI- WATER, SUS- DATE FLTRD, FLTRD, TION FLTRD, MG/L AS UNFLTRD FLTRD, FLTRD, FLTRD, FLTRD, TUENTS FLTRD, PENDED, MG/L MG/L RATIO MG/L CACO3 MG/L MG/L MG/L MG/L MG/L MG/L TONS/D MG/L (00925) (00930) (00931) (00935) (00410) (00745) (00945) (00940) (00950) (00955) (70301) (70302) (00530) DEC 17... 7.39 11.7 .5 1.72 88 <1.0 6.5 12.7 .1 27.2 143 15.6 10 MAR 12... -- -- -- -- 97 -- -- -- -- -- -- -- <10 SEP 10... 8.34 17.0 .7 1.66 87 <.1 6.4 20.9 E.08 27.3 161 -- 50 NITRITE AMMONIA CHROM- + + BARIUM, BORON, IUM, COPPER, IRON, LEAD, NITRITE NITRATE AMMONIA ORG-N, PHOS- WATER, WATER, WATER, WATER, WATER, WATER, WATER, WATER WATER, WATER, PHORUS, ARSENIC UNFLTRD UNFLTRD CADMIUM UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD WATER, WATER RECOV- RECOV- WATER, RECOV- RECOV- RECOV- RECOV- DATE MG/L MG/L MG/L MG/L UNFLTRD UNFLTRD ERABLE, ERABLE, UNFLTRD ERABLE, ERABLE, ERABLE, ERABLE, AS N AS N AS N AS N MG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L (00615) (00630) (00610) (00625) (00665) (01002) (01007) (01022) (01027) (01034) (01042) (01045) (01051) DEC 17... <.01 .950 .05 .20 .07 <2 14.7 E10 <.1 E.5 <10 160 M MAR 12... <.01 1.20 .03 <.20 .10 -- -- -- -- -- -- -- -- SEP 10... .02 .590 .03 .30 .09 2 12.1 140 <.1 2.1 <10 M <1 MANGAN- PHEN- ESE, MERCURY SILVER, ZINC, OLIC WATER, WATER, SELEN- WATER, WATER, COM- UNFLTRD UNFLTRD IUM, UNFLTRD UNFLTRD CYANIDE POUNDS, MBAS, RECOV- RECOV- WATER, RECOV- RECOV- WATER WATER, WATER, DATE ERABLE, ERABLE, UNFLTRD ERABLE, ERABLE, UNFLTRD UNFLTRD UNFLTRD UG/L UG/L UG/L UG/L UG/L MG/L UG/L MG/L (01055) (71900) (01147) (01077) (01092) (00720) (32730) (38260) DEC 17... 22.7 <.01 <4 <.3 <20 <.01 <16 <.05 MAR 12... -- -- -- -- -- -- -- -- SEP 10... E2.3 <.01 <2 <.3 <20 <.01 <16 <.05 < -- Less than E -- Estimated value M -- Presence verified, not quantified 73 RIO GRANDE DE ARECIBO BASIN 50020500 RIO GRANDE DE ARECIBO NEAR ADJUNTAS, PR--Continued WATER-QUALITY RECORDS SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) OCTOBER NOVEMBER DECEMBER 1 26 18 1.3 34 8 0.70 26 21 1.4 2 25 7 0.45 73 178 132 14 20 0.75 3 25 6 0.42 40 36 4.0 91 180 110 4 23 6 0.38 59 81 20 43 51 6.7 5 27 17 1.4 47 45 6.0 31 25 2.1 6 33 35 3.1 65 95 25 28 14 1.1 7 37 43 4.6 44 10 1.3 24 3 0.24 8 31 19 1.7 287 637 790 16 1 0.04 9 33 12 1.1 101 148 53 19 7 0.65 10 155 491 575 55 32 4.8 20 1 0.05 11 57 91 17 70 84 22 97 471 364 12 35 29 2.7 61 84 15 48 62 14 13 33 23 2.1 63 105 28 24 7 0.44 14 30 23 1.8 100 240 180 22 6 0.36 15 49 101 31 65 58 11 19 6 0.29 16 34 15 1.4 53 20 2.9 84 160 125 17 29 4 0.35 43 18 2.1 173 468 773 18 29 3 0.27 40 17 1.8 e78 e128 e33.0 19 32 4 0.33 38 15 1.6 54 71 10 20 29 4 0.31 39 10 0.99 41 48 5.4 21 30 4 0.33 34 4 0.34 65 128 71 22 157 479 1060 25 3 0.21 39 45 4.7 23 114 694 825 31 7 0.61 41 38 4.2 24 47 61 7.9 38 29 3.2 36 31 3.0 25 39 42 4.4 32 18 1.5 32 25 2.1 26 36 32 3.1 31 16 1.3 27 18 1.3 27 33 40 4.5 29 15 1.2 20 16 0.85 28 65 190 102 29 15 1.2 20 16 0.86 29 75 141 48 44 45 6.0 18 16 0.79 30 93 236 119 31 27 2.3 18 16 0.79 31 45 39 5.6 --- --- --- 18 16 0.80 TOTAL 1506 --- 2826.54 1701 --- 1320.05 1286 --- 1538.91 74 RIO GRANDE DE ARECIBO BASIN 50020500 RIO GRANDE DE ARECIBO NEAR ADJUNTAS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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 FEBRUARY MARCH 1 22 16 0.97 18 9 0.44 12 9 0.28 2 26 15 1.1 14 12 0.48 11 8 0.24 3 28 14 1.0 16 16 0.68 11 6 0.19 4 25 12 0.85 19 19 0.98 11 5 0.15 5 24 11 0.71 14 22 0.86 11 4 0.13 6 25 10 0.65 15 19 0.81 10 4 0.11 7 23 9 0.52 16 15 0.67 10 3 0.09 8 26 7 0.52 14 11 0.43 11 3 0.09 9 26 9 0.65 15 11 0.44 11 3 0.09 10 20 12 0.64 15 12 0.49 9.9 3 0.08 11 24 14 0.92 14 14 0.53 49 160 89 12 20 12 0.62 14 15 0.58 17 18 0.91 13 24 8 0.50 14 17 0.64 11 11 0.34 14 26 4 0.29 14 19 0.69 11 8 0.25 15 23 3 0.21 13 19 0.69 11 6 0.16 16 22 4 0.23 13 19 0.65 13 5 0.16 17 23 5 0.31 13 19 0.66 13 4 0.14 18 16 6 0.29 14 19 0.73 11 4 0.11 19 16 10 0.42 35 55 7.6 11 3 0.10 20 15 13 0.56 16 22 0.97 10 5 0.13 21 16 17 0.71 13 15 0.53 10 7 0.18 22 19 20 1.0 12 9 0.29 9.5 7 0.18 23 22 16 0.95 12 10 0.33 8.9 7 0.16 24 22 11 0.65 11 14 0.44 8.7 7 0.15 25 23 6 0.39 11 18 0.54 8.7 6 0.15 26 23 5 0.29 14 16 0.61 8.9 6 0.15 27 22 4 0.26 13 12 0.42 8.8 6 0.15 28 21 4 0.22 12 10 0.32 9.1 8 0.20 29 16 3 0.15 --- --- --- 59 387 255 30 16 3 0.14 --- --- --- 17 14 0.72 31 16 6 0.24 --- --- --- 38 74 26 TOTAL 670 --- 16.96 414 --- 23.50 451.5 --- 375.79 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) APRIL MAY JUNE 1 19 15 0.92 49 12 1.6 17 101 4.7 2 14 10 0.41 75 136 44 22 100 6.0 3 12 14 0.46 52 38 5.8 51 115 17 4 11 18 0.52 56 56 11 146 219 156 5 192 607 1380 43 54 6.3 72 72 14 6 83 157 59 45 105 25 53 64 9.2 7 42 37 4.6 45 44 4.9 43 57 6.6 8 40 30 3.7 35 12 1.1 36 49 4.8 9 32 8 0.68 40 14 1.5 34 42 3.8 10 24 8 0.52 59 280 110 31 38 3.1 11 19 8 0.43 42 87 10 29 59 4.5 12 18 9 0.42 31 59 4.9 30 53 4.2 13 13 9 0.33 29 57 4.5 28 35 2.7 14 13 10 0.36 30 55 4.5 22 17 1.1 15 17 10 0.49 26 53 3.8 18 15 0.74 16 19 11 0.54 30 58 4.8 20 20 1.1 17 53 144 78 27 66 4.8 23 24 1.5 18 23 20 1.3 16 74 3.1 29 27 2.1 19 18 16 0.79 15 81 3.3 23 30 1.9 20 230 478 554 15 89 3.6 27 47 5.4 21 149 265 162 15 97 3.8 13 24 0.87 22 54 66 9.9 14 112 4.3 12 24 0.80 23 302 1390 3780 14 129 5.0 14 24 0.93 24 245 938 1110 14 127 4.8 18 24 1.2 25 344 1320 2220 13 116 4.2 17 24 1.1 26 317 1290 2050 14 105 3.9 24 34 3.2 27 245 755 638 14 94 3.7 19 27 1.4 28 161 359 183 15 83 3.3 19 25 1.3 29 82 95 24 18 73 3.5 14 23 0.83 30 62 34 6.3 32 81 7.1 19 20 1.0 31 --- --- --- 25 97 6.5 --- --- --- TOTAL 2853 --- 12270.67 948 --- 308.6 923 --- 263.07 75 RIO GRANDE DE ARECIBO BASIN 50020500 RIO GRANDE DE ARECIBO NEAR ADJUNTAS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) JULY AUGUST SEPTEMBER 1 19 18 0.93 15 22 0.88 65 109 25 2 17 22 1.0 13 22 0.75 152 472 514 3 12 28 0.87 11 22 0.65 287 1120 2070 4 9.9 29 0.77 13 21 0.76 154 503 389 5 11 29 0.84 54 149 51 47 58 8.7 6 21 34 2.2 29 31 2.8 29 21 1.6 7 22 10 0.79 31 34 4.0 34 21 1.9 8 15 1 0.06 36 63 6.2 31 21 1.7 9 16 20 0.79 24 46 2.9 28 21 1.6 10 12 34 1.1 23 34 2.1 40 49 7.9 11 14 20 0.80 27 36 3.0 37 38 4.2 12 10 16 0.44 21 13 0.82 32 21 1.8 13 8.7 15 0.35 19 29 3.7 212 723 1180 14 15 23 2.5 34 94 32 68 138 34 15 40 43 7.0 21 3 0.18 159 409 328 16 19 5 0.27 32 108 48 131 201 90 17 15 6 0.24 13 11 0.39 61 7 1.2 18 11 6 0.18 e63 e58 e19.0 55 5 0.70 19 9.4 6 0.15 32 32 3.5 38 5 0.48 20 9.6 6 0.15 21 9 0.49 34 6 0.53 21 14 6 0.22 30 26 3.9 34 7 0.62 22 21 16 1.5 29 30 2.7 34 8 0.71 23 18 14 0.70 18 17 0.83 32 9 0.77 24 15 11 0.45 17 14 0.66 e33 e10 e0.86 25 8.6 9 0.21 38 37 6.3 41 9 0.98 26 11 7 0.20 91 50 25 32 7 0.61 27 13 6 0.20 64 19 3.6 29 5 0.43 28 17 31 2.9 98 198 130 21 5 0.29 29 14 8 0.31 45 e58 8.2 12 5 0.16 30 45 29 12 103 245 248 11 5 0.14 31 41 53 7.4 87 184 54 --- --- --- TOTAL 524.2 --- 47.52 1152 --- 666.31 1973 --- 4667.88 YEAR 14401.7 24325.80 e Estimated WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT Sus- Suspnd. pended Sus- sedi- Instan- sedi- pended ment, taneous ment sedi- sieve dis- concen- ment diametr Date Time charge, tration load, percent cfs mg/L tons/d <.062mm (00061) (80154) (80155) (70331) OCT 22... 1706 1440 5680 22100 82 DEC 11... 1635 467 3730 4700 95 MAR 29... 1600 480 4240 5490 98 76 RIO GRANDE DE ARECIBO BASIN 50021030 RIO PELLEJAS ABOVE CENTRAL PELLEJAS, PR LOCATION.--Lat 18°12'17',long 66°42'13", Hydrologic Unit 21010002, 0.2 mi (0.3 km) southeast from Escuela Lucas Valdivieso, 3.0 mi (4.8 km) north from Adjuntas Hospital and 2.0 mi (3.2 km) west from Lago Adjuntas. DRAINAGE AREA.--2.99 mi2 (7.74 km2). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--May 2000 to current year. GAGE.--Water-stage recorder. Elevation of gage is 1,148 ft (350 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 2001 TO SEPTEMBER 2002 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 14 13 15 13 10 22 28 24 23 22 e22 e25 2 14 25 15 13 10 22 27 34 23 23 e22 e39 3 14 17 34 13 10 21 26 26 24 23 25 e59 4 14 14 17 13 10 21 25 26 e25 22 21 e50 5 14 15 15 14 10 21 60 25 e22 22 22 e27 6 13 21 14 15 9.9 21 35 24 e21 24 21 e20 7 13 16 14 14 9.9 21 28 25 e21 23 21 e23 8 13 110 14 13 9.8 21 28 23 e21 22 21 e21 9 14 35 16 13 9.7 21 25 22 e21 22 21 e20 10 16 22 14 12 9.6 21 23 34 e21 22 23 e24 11 14 27 47 12 10 30 23 23 22 21 23 e24 12 13 21 21 12 28 24 22 22 23 21 23 e21 13 13 33 16 12 20 23 22 22 e21 21 26 e44 14 13 22 15 12 21 23 22 22 22 22 27 e26 15 18 20 14 12 21 23 23 22 e20 23 22 e40 16 14 18 28 12 21 23 24 21 e20 22 21 e35 17 13 18 53 12 23 23 28 21 e21 22 21 e25 18 12 17 e23 12 24 23 42 21 e24 21 e32 e24 19 12 17 20 11 29 23 33 21 e25 20 23 e20 20 12 16 17 11 25 22 73 21 22 20 22 e18 21 12 16 34 11 24 22 50 22 21 20 e22 e18 22 25 15 18 11 24 21 38 23 21 20 e23 e18 23 28 15 18 11 23 21 59 23 21 21 e22 e17 24 16 16 16 11 23 21 59 23 21 20 21 e17 25 13 15 15 11 23 22 58 23 20 20 22 e22 26 13 15 14 11 23 22 84 23 21 20 e23 e20 27 14 15 14 11 23 22 54 23 21 20 e23 e20 28 21 15 13 11 22 23 38 23 21 23 30 e18 29 25 19 13 11 --- 39 29 22 21 e22 e25 e17 30 16 15 13 11 --- 25 26 23 21 e21 e27 e17 31 14 --- 13 11 --- 32 --- 23 --- e21 e27 --- TOTAL 470 653 603 372 505.9 719 1112 730 651 666 724 769 MEAN 15.2 21.8 19.5 12.0 18.1 23.2 37.1 23.5 21.7 21.5 23.4 25.6 MAX 28 110 53 15 29 39 84 34 25 24 32 59 MIN 12 13 13 11 9.6 21 22 21 20 20 21 17 AC-FT 932 1300 1200 738 1000 1430 2210 1450 1290 1320 1440 1530 CFSM 2.22 3.19 2.85 1.76 2.65 3.40 5.43 3.45 3.18 3.15 3.42 3.75 IN. 2.56 3.56 3.28 2.03 2.76 3.92 6.06 3.98 3.55 3.63 3.94 4.19 STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 2000 - 2002, BY WATER YEAR (WY) MEAN 39.2 30.6 24.9 21.2 20.4 21.0 27.8 29.1 35.7 29.5 26.1 33.2 MAX 63.2 39.5 30.3 30.4 22.8 23.2 37.1 34.6 57.2 36.7 33.7 49.0 (WY) 2001 2001 2001 2001 2001 2002 2002 2001 2000 2000 2000 2000 MIN 15.2 21.8 19.5 12.0 18.1 18.9 18.6 23.5 21.7 21.5 21.3 24.9 (WY) 2002 2002 2002 2002 2002 2001 2001 2002 2002 2002 2001 2001 SUMMARY STATISTICS FOR 2001 CALENDAR YEAR FOR 2002 WATER YEAR WATER YEARS 2000 - 2002 ANNUAL TOTAL 8707 7974.9 ANNUAL MEAN 23.9 21.8 26.1 HIGHEST ANNUAL MEAN 30.3 2001 LOWEST ANNUAL MEAN 21.8 2002 HIGHEST DAILY MEAN 232 May 6 110 Nov 8 232 May 6 2001 LOWEST DAILY MEAN 12 Oct 18 9.6 Feb 10 9.6 Feb 10 2002 ANNUAL SEVEN-DAY MINIMUM 13 Oct 15 9.8 Feb 4 9.8 Feb 4 2002 MAXIMUM PEAK FLOW 824 Dec 17 2290 May 6 2001 MAXIMUM PEAK STAGE 7.23 Dec 17 9.42 May 6 2001 INSTANTANEOUS LOW FLOW 14 Apr 17 2001 ANNUAL RUNOFF (AC-FT) 17270 15820 18890 ANNUAL RUNOFF (CFSM) 3.49 3.20 3.82 ANNUAL RUNOFF (INCHES) 47.42 43.44 51.88 10 PERCENT EXCEEDS 33 28 37 50 PERCENT EXCEEDS 21 21 23 90 PERCENT EXCEEDS 15 12 14 e Estimated 77 RIO GRANDE DE ARECIBO BASIN 50021030 RIO PELLEJAS ABOVE CENTRAL PELLEJAS, PR--Continued O N D 2001 J F M A M J J A S 2002 1 2 5 10 10 20 50 100 100 200 500 1000 DISCHARGE, IN CUBIC FEET PER SECOND 78 RIO GRANDE DE ARECIBO BASIN 50021030 RIO PELLEJAS ABOVE CENTRAL PELLEJAS, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--May 2000 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: October 2000 to current year. INSTRUMENTATION.-- USDH-48 and automatic sediment samplers since 2000. REMARKS.-- Sediment samples were collected by a local observer on a weekly basis. During high flow events sediment samples were collected with automatic sediment sampler. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATION: Maximum daily mean, e1,070 mg/L September 3, 2002; Minimum daily mean, 2.0 mg/L several days during Water Year 2002. SEDIMENT LOADS: Maximum daily mean, 2,810 tons (2,549 tonnes) May 6, 2001; Minimum daily mean, 0.06 ton (0.05 tonne) several days during Water Year 2002. EXTREMES FOR CURRENT YEAR 2002.-- SEDIMENT CONCENTRATION: Maximum daily mean, e1,070 mg/L September 3, 2002; Minimum daily mean, 2.0 mg/L several days. SEDIMENT LOADS: Maximum daily mean, e1,210 tons (e1,098 tonnes) September 3, 2002; Minimum daily mean, 0.06 ton (0.05 tonne) several days. SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) OCTOBER NOVEMBER DECEMBER 1 14 15 0.56 13 15 0.54 15 6 0.24 2 14 9 0.33 25 88 18 15 6 0.24 3 14 8 0.31 17 24 1.2 34 81 19 4 14 10 0.36 14 15 0.58 17 9 0.42 5 14 9 0.34 15 13 0.52 15 6 0.26 6 13 8 0.30 21 31 2.1 14 6 0.23 7 13 7 0.26 16 8 0.34 14 6 0.23 8 13 6 0.22 110 639 354 14 6 0.21 9 14 5 0.19 35 78 8.2 16 14 0.85 10 16 13 0.59 22 37 2.2 14 15 0.56 11 14 7 0.28 27 55 7.3 47 298 118 12 13 5 0.17 21 27 1.6 21 37 2.2 13 13 5 0.16 33 81 18 16 17 0.74 14 13 4 0.15 22 18 1.1 15 15 0.60 15 18 26 2.2 20 13 0.71 14 13 0.51 16 14 4 0.16 18 22 1.1 28 87 16 17 13 5 0.17 18 32 1.5 53 395 360 18 12 7 0.24 17 30 1.4 e23 e27 e1.9 19 12 8 0.24 17 23 1.1 20 11 0.61 20 12 8 0.25 16 17 0.76 17 10 0.45 21 12 8 0.24 16 11 0.48 34 140 34 22 25 110 29 15 5 0.22 18 25 1.2 23 28 122 25 15 4 0.15 18 19 0.93 24 16 29 1.2 16 3 0.14 16 14 0.58 25 13 26 0.92 15 3 0.13 15 9 0.35 26 13 24 0.85 15 3 0.14 14 6 0.25 27 14 23 0.85 15 4 0.15 14 5 0.18 28 21 52 6.3 15 4 0.16 13 3 0.12 29 25 76 12 19 5 0.24 13 3 0.12 30 16 22 0.96 15 6 0.24 13 4 0.14 31 14 19 0.70 --- --- --- 13 5 0.16 TOTAL 470 --- 85.50 653 --- 424.30 603 --- 561.28 79 RIO GRANDE DE ARECIBO BASIN 50021030 RIO PELLEJAS ABOVE CENTRAL PELLEJAS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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 FEBRUARY MARCH 1 13 5 0.18 10 3 0.09 22 61 3.6 2 13 7 0.25 10 4 0.11 22 83 4.9 3 13 10 0.33 10 3 0.09 21 75 4.4 4 13 11 0.39 10 3 0.08 21 62 3.5 5 14 10 0.37 10 2 0.06 21 48 2.7 6 15 7 0.30 9.9 3 0.07 21 39 2.2 7 14 5 0.17 9.9 3 0.09 21 31 1.8 8 13 3 0.09 9.8 4 0.10 21 24 1.4 9 13 4 0.13 9.7 4 0.10 21 22 1.3 10 12 6 0.20 9.6 3 0.09 21 22 1.2 11 12 8 0.26 10 6 0.28 30 22 1.8 12 12 8 0.25 28 121 12 24 22 1.5 13 12 7 0.23 20 70 3.7 23 36 2.3 14 12 7 0.22 21 79 4.5 23 50 3.1 15 12 6 0.20 21 89 5.2 23 60 3.7 16 12 6 0.19 21 99 5.7 23 53 3.3 17 12 5 0.16 23 88 5.6 23 44 2.7 18 12 4 0.13 24 71 4.5 23 35 2.1 19 11 4 0.12 29 67 5.3 23 35 2.1 20 11 3 0.10 25 61 4.1 22 93 5.6 21 11 3 0.09 24 54 3.5 22 124 7.4 22 11 2 0.07 24 47 3.0 21 146 8.4 23 11 2 0.06 23 41 2.6 21 169 9.6 24 11 2 0.06 23 40 2.5 21 187 11 25 11 2 0.06 23 40 2.5 22 157 9.2 26 11 2 0.06 23 41 2.6 22 112 6.7 27 11 2 0.06 23 41 2.5 22 69 4.2 28 11 2 0.06 22 42 2.5 23 43 2.7 29 11 2 0.06 --- --- --- 39 132 25 30 11 2 0.06 --- --- --- 25 37 2.5 31 11 3 0.08 --- --- --- 32 81 12 TOTAL 372 --- 4.99 505.9 --- 73.46 719 --- 153.9 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) APRIL MAY JUNE 1 28 76 6.7 24 10 0.65 23 10 0.59 2 27 50 3.7 34 62 11 23 10 0.64 3 26 41 2.9 26 25 1.7 24 11 0.71 4 25 37 2.5 26 26 1.8 e25 e12 e0.87 5 60 453 184 25 25 1.6 e22 e17 e1.0 6 35 103 13 24 27 1.9 e21 e17 e1.0 7 28 29 2.2 25 29 2.1 e21 e17 e1.0 8 28 28 2.1 23 19 1.2 e21 e17 e1.0 9 25 28 1.9 22 16 0.94 e21 e17 e1.0 10 23 23 1.5 34 62 17 e21 e17 e1.0 11 23 19 1.2 23 16 1.0 22 17 1.0 12 22 18 1.1 22 13 0.80 23 18 1.1 13 22 17 1.0 22 12 0.71 e21 e19 e1.1 14 22 17 0.97 22 11 0.63 22 19 1.1 15 23 16 1.0 22 10 0.57 e20 e20 e1.2 16 24 16 1.0 21 8 0.49 e20 e20 e1.2 17 28 38 3.6 21 7 0.42 e21 e20 e1.2 18 42 254 64 21 7 0.42 e24 e21 e1.3 19 33 84 7.8 21 8 0.44 e25 e21 e1.3 20 73 397 124 21 8 0.47 22 21 1.3 21 50 204 33 22 9 0.52 21 20 1.2 22 38 86 8.8 23 9 0.59 21 20 1.2 23 59 353 162 23 11 0.71 21 23 1.3 24 59 391 183 23 14 0.83 21 27 1.5 25 58 343 116 23 16 0.97 20 31 1.7 26 84 893 699 23 25 1.5 21 35 2.0 27 54 273 80 23 35 2.2 21 39 2.3 28 38 57 7.0 23 46 2.8 21 43 2.5 29 29 15 1.2 22 56 3.4 21 47 2.7 30 26 8 0.59 23 49 3.0 21 45 2.5 31 --- --- --- 23 29 1.8 --- --- --- TOTAL 1112 --- 1716.76 730 --- 64.16 651 --- 39.51 80 RIO GRANDE DE ARECIBO BASIN 50021030 RIO PELLEJAS ABOVE CENTRAL PELLEJAS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) JULY AUGUST SEPTEMBER 1 22 40 2.4 e22 e24 e1.3 e25 e24 e1.5 2 23 36 2.2 e22 e23 e1.3 e39 e101 e15 3 23 31 1.9 25 35 2.7 e59 e1070 e1210 4 22 27 1.6 21 24 1.4 e50 e204 e33 5 22 30 1.8 22 33 2.0 e27 e55 e4.3 6 24 34 2.2 21 46 2.6 e20 e27 e1.4 7 23 33 2.1 21 37 2.1 e23 e27 e1.4 8 22 32 1.9 21 21 1.2 e21 e27 e1.4 9 22 30 1.8 21 16 0.92 e20 e27 e1.4 10 22 28 1.7 23 16 0.96 e24 e35 e2.7 11 21 26 1.5 23 15 0.96 e24 e35 e2.7 12 21 25 1.4 23 15 0.94 e21 e35 e2.7 13 21 26 1.4 26 33 2.8 e44 e57 e7.0 14 22 28 1.6 27 55 4.3 e26 e35 e2.7 15 23 30 1.8 22 65 3.9 e40 e57 e7.0 16 22 31 1.9 21 44 2.5 e35 e57 e7.0 17 22 32 1.9 21 42 2.4 e25 e35 e2.7 18 21 31 1.8 e32 e72 e6.7 e24 e35 e2.7 19 20 30 1.7 23 73 4.5 e20 e27 e1.4 20 20 30 1.6 22 69 4.0 e18 e27 e1.4 21 20 29 1.6 e22 e43 e2.5 e18 e27 e1.4 22 20 29 1.6 e23 e34 e2.0 e18 e27 e1.4 23 21 28 1.6 e22 e35 e2.0 e17 e27 e1.4 24 20 28 1.5 21 37 2.1 e17 e49 e3.1 25 20 27 1.4 22 60 3.6 e22 e27 e1.5 26 20 27 1.4 e23 e73 e4.2 e20 e34 e1.7 27 20 26 1.4 e23 e78 e4.5 e20 e41 e1.9 28 23 26 1.6 30 97 9.6 e18 e41 e2.0 29 e22 e25 e1.4 e25 e29 e1.9 e17 e41 e2.0 30 e21 e25 e1.3 e27 e29 e2.1 e17 e40 e2.0 31 e21 e24 e1.3 e27 e36 e2.8 --- --- --- TOTAL 666 --- 52.3 724 --- 86.78 769 --- 1327.8 YEAR 7974.9 4590.74 e Estimated WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT Sus- Suspnd. pended Sus- sedi- Instan- sedi- pended ment, taneous ment sedi- sieve dis- concen- ment diametr Date Time charge, tration load, percent cfs mg/L tons/d <.063mm (00061) (80154) (80155) (70331) APR 05... 1800 144 1660 644 96 24... 1825 227 2910 1790 99 81 RIO GRANDE DE ARECIBO BASIN 50021700 RIO GRANDE DE ARECIBO ABOVE UTUADO, PR LOCATION.--Lat 18°14'39", long 66°43'20", Hydrologic Unit 21010001, 0.4 mi (0.6 km) southwest from Escuela Segunda Unidad Salto Arriba, 2.2 mi (3.5 km) southwest from Utuado Plaza, 1.1 mi (1.8 km) west from Escuela Arenas Abajo and 1.0 mi (1.7 km) northwest from Escuela Puente Blanco. DRAINAGE AREA.--36.0 mi2 (93.2 km2). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--August 1989 to May 1999, monthly measurements and peak flow above 5,000 ft3/s (142 m3/s), June 1999 to current year. GAGE.--Water-stage recorder. Elevation of gage is 508 ft (155 m), from topographic map. REMARKS.--Records fair except those for estimated daily discharges, which are poor. Flow regulated by Lago Adjuntas 2.55 mi (4.10 km). Gage-height and precipitation satellite telemetry at station. Discharge, cubic feet per second WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 51 41 41 36 e17 6.1 52 94 24 23 20 74 2 49 136 47 39 e15 6.0 20 173 26 20 13 171 3 47 74 140 41 e15 5.9 8.0 101 39 17 12 363 4 47 60 80 41 e16 5.9 6.2 84 96 15 16 213 5 47 63 51 39 e14 5.8 379 73 66 14 30 82 6 56 79 46 43 e13 5.7 187 63 50 17 34 35 7 59 69 42 37 e13 5.5 73 70 42 30 17 34 8 58 905 33 38 e13 6.0 109 53 35 22 31 30 9 54 324 33 41 e11 6.2 55 75 36 33 22 27 10 185 120 36 33 e11 7.0 37 83 33 20 22 26 11 97 108 231 36 e10 61 29 68 31 29 32 38 12 51 110 92 32 e18 27 28 46 34 31 27 26 13 58 101 49 35 8.4 6.5 22 42 34 18 24 138 14 48 153 43 36 7.8 5.0 20 42 30 16 41 84 15 69 99 38 34 7.5 4.8 22 40 24 31 26 93 16 47 79 140 32 7.3 5.6 53 40 26 23 25 133 17 43 66 320 e34 6.8 7.9 64 42 27 20 18 58 18 38 60 143 e27 6.8 5.0 69 30 30 17 55 89 19 44 57 70 e25 18 4.7 66 27 28 15 44 89 20 40 56 53 e24 17 4.5 373 27 30 17 40 39 21 42 53 117 e23 8.3 4.4 377 28 22 16 24 36 22 215 40 73 e23 7.2 4.3 112 26 18 24 52 34 23 207 45 70 e25 6.7 4.3 556 25 18 27 29 30 24 80 56 64 e25 6.6 4.3 526 24 22 22 26 30 25 53 47 54 e24 6.5 4.3 508 24 22 18 24 36 26 44 46 49 e23 6.4 4.5 502 23 33 15 31 30 27 43 43 39 e23 6.3 4.3 379 23 29 18 70 28 28 84 45 37 e23 6.1 6.9 284 23 25 42 53 24 29 94 63 35 e19 --- 38 147 23 20 32 50 16 30 103 51 33 e17 --- 25 119 34 21 21 58 13 31 62 --- 33 e16 --- 28 --- 33 --- 73 93 --- TOTAL 2215 3249 2332 944 299.7 320.4 5182.2 1559 971 736 1059 2119 MEAN 71.5 108 75.2 30.5 10.7 10.3 173 50.3 32.4 23.7 34.2 70.6 MAX 215 905 320 43 18 61 556 173 96 73 93 363 MIN 38 40 33 16 6.1 4.3 6.2 23 18 14 12 13 AC-FT 4390 6440 4630 1870 594 636 10280 3090 1930 1460 2100 4200 CFSM 1.98 3.01 2.09 0.85 0.30 0.29 4.80 1.40 0.90 0.66 0.95 1.96 IN. 2.29 3.36 2.41 0.98 0.31 0.33 5.35 1.61 1.00 0.76 1.09 2.19 STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1999 - 2002, BY WATER YEAR (WY) MEAN 161 147 61.1 20.3 9.19 7.17 67.8 84.0 48.2 25.4 78.1 148 MAX 239 220 75.2 30.5 10.8 10.3 173 102 90.2 31.5 135 224 (WY) 2001 2000 2002 2002 2000 2002 2002 2001 2000 2000 2000 1999 MIN 71.5 108 43.4 8.38 6.06 4.55 9.58 50.3 10.2 21.7 30.0 70.6 (WY) 2002 2002 2001 2001 2001 2001 2000 2002 2001 2001 2001 2002 SUMMARY STATISTICS FOR 2001 CALENDAR YEAR FOR 2002 WATER YEAR WATER YEARS 1999 - 2002 ANNUAL TOTAL 17500.9 20986.3 ANNUAL MEAN 47.9 57.5 68.2 HIGHEST ANNUAL MEAN 87.2 2000 LOWEST ANNUAL MEAN 57.5 2002 HIGHEST DAILY MEAN 1760 May 6 905 Nov 8 2210 Aug 23 2000 LOWEST DAILY MEAN 3.7 Mar 30 4.3 Mar 22 3.7 Mar 30 2001 ANNUAL SEVEN-DAY MINIMUM 3.8 Mar 27 4.3 Mar 21 3.8 Mar 27 2001 MAXIMUM PEAK FLOW 3520 Apr 23 45600 Sep 22 1998 MAXIMUM PEAK STAGE 7.33 Apr 23 19.72 Sep 22 1998 ANNUAL RUNOFF (AC-FT) 34710 41630 49440 ANNUAL RUNOFF (CFSM) 1.33 1.60 1.90 ANNUAL RUNOFF (INCHES) 18.08 21.69 25.75 10 PERCENT EXCEEDS 103 105 155 50 PERCENT EXCEEDS 12 34 30 90 PERCENT EXCEEDS 5.0 7.4 5.7 e Estimated 82 RIO GRANDE DE ARECIBO BASIN 50021700 RIO GRANDE DE ARECIBO ABOVE UTUADO, PR--Continued O N D 2001 J F M A M J J A S 2002 1 2 5 10 10 20 50 100 100 200 500 1000 DISCHARGE, IN CUBIC FEET PER SECOND 83 RIO GRANDE DE ARECIBO BASIN 50021700 RIO GRANDE DE ARECIBO ABOVE UTUADO, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--June 1999 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: October 2000 to current year. INSTRUMENTATION.-- USDH-48 and automatic sediment samplers since 1999. REMARKS.-- Sediment samples were collected by a local observer on a weekly basis. During high flow events sediment samples were collected with automatic sediment sampler. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATION: Maximum daily mean, e1,600 mg/L May 6, 2001; Minimum daily mean, 1 mg/L several days during water years 2001 and 2002. SEDIMENT LOADS: Maximum daily mean, e32,200 tons (e29,210 tonnes) May 6, 2001; Minimum daily mean, 0.01 ton (0.01 tonne) April 13-15, 2001. EXTREMES FOR CURRENT YEAR 2002.-- SEDIMENT CONCENTRATION: Maximum daily mean, 1,370 mg/L November 8, 2001; Minimum daily mean, 1 mg/L several days. SEDIMENT LOADS: Maximum daily mean, 4,830 tons (4,382 tonnes) November 8, 2001; Minimum daily mean, 0.03 ton (0.03 tonne) March 22, 24, 2002. SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) OCTOBER NOVEMBER DECEMBER 1 51 28 3.8 41 72 8.0 41 1 0.11 2 49 25 3.3 136 222 239 47 30 5.2 3 47 23 2.9 74 139 36 140 211 255 4 47 20 2.6 60 109 21 80 115 33 5 47 18 2.3 63 110 19 51 2 0.26 6 56 15 2.3 79 143 36 46 2 0.22 7 59 27 4.9 69 120 27 42 2 0.18 8 58 44 7.3 905 1370 4830 33 1 0.13 9 54 12 1.8 324 494 477 33 1 0.12 10 185 288 382 120 226 76 36 1 0.11 11 97 150 56 108 202 67 231 318 533 12 51 11 1.5 110 201 66 92 178 53 13 58 52 10 101 187 67 49 84 12 14 48 11 1.4 153 297 232 43 69 8.0 15 69 46 19 99 181 50 38 69 7.1 16 47 11 1.4 79 123 26 140 251 260 17 43 10 1.2 66 84 15 320 545 1240 18 38 10 0.98 60 45 7.3 143 158 96 19 44 9 1.1 57 10 1.6 70 63 12 20 40 8 0.90 56 4 0.61 53 47 6.6 21 42 8 0.88 53 2 0.25 117 210 155 22 215 383 915 40 1 0.16 73 77 19 23 207 376 550 45 2 0.23 70 35 6.7 24 80 138 35 56 45 7.6 64 28 4.9 25 53 93 14 47 1 0.13 54 21 3.1 26 44 73 8.7 46 1 0.13 49 14 1.8 27 43 71 9.0 43 1 0.12 39 8 0.87 28 84 153 57 45 1 0.12 37 8 0.80 29 94 175 60 63 62 13 35 8 0.75 30 103 200 79 51 29 4.6 33 8 0.71 31 62 114 21 --- --- --- 33 8 0.69 TOTAL 2215 --- 2256.26 3249 --- 6327.85 2332 --- 2716.35 84 RIO GRANDE DE ARECIBO BASIN 50021700 RIO GRANDE DE ARECIBO ABOVE UTUADO, PR--Continued EDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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 FEBRUARY MARCH 1 36 8 0.75 e17 e5 e0.21 6.1 6 0.11 2 39 8 0.81 e15 e4 e0.18 6.0 8 0.12 3 41 8 0.84 e15 e4 e0.17 5.9 7 0.11 4 41 8 0.84 e16 e4 e0.18 5.9 5 0.08 5 39 8 0.79 e14 e4 e0.16 5.8 4 0.07 6 43 8 0.87 e13 e5 e0.17 5.7 5 0.07 7 37 7 0.74 e13 e5 e0.19 5.5 5 0.08 8 38 7 0.76 e13 e6 e0.20 6.0 6 0.10 9 41 7 0.81 e11 e6 e0.17 6.2 6 0.10 10 33 7 0.65 e11 e5 e0.16 7.0 6 0.11 11 36 7 0.71 e10 e5 e0.14 61 117 56 12 32 7 0.63 e18 e28 e2.5 27 51 6.6 13 35 7 0.67 8.4 13 0.29 6.5 8 0.14 14 36 7 0.70 7.8 12 0.26 5.0 8 0.11 15 34 7 0.66 7.5 12 0.25 4.8 5 0.07 16 32 7 0.60 7.3 12 0.24 5.6 5 0.08 17 e34 e7 e0.64 6.8 12 0.22 7.9 6 0.12 18 e27 e7 e0.50 6.8 12 0.22 5.0 6 0.08 19 e25 e7 e0.46 18 20 1.1 4.7 5 0.07 20 e24 e7 e0.42 17 13 0.74 4.5 4 0.05 21 e23 e6 e0.40 8.3 4 0.10 4.4 3 0.04 22 e23 e6 e0.39 7.2 4 0.07 4.3 3 0.03 23 e25 e6 e0.41 6.7 3 0.06 4.3 3 0.04 24 e25 e6 e0.39 6.6 3 0.05 4.3 3 0.03 25 e24 e6 e0.37 6.5 2 0.04 4.3 3 0.04 26 e23 e6 e0.35 6.4 2 0.04 4.5 3 0.04 27 e23 e5 e0.33 6.3 3 0.06 4.3 3 0.04 28 e23 e5 e0.32 6.1 5 0.08 6.9 7 0.21 29 e19 e5 e0.26 --- --- --- 38 66 28 30 e17 e5 e0.23 --- --- --- 25 43 6.2 31 e16 e5 e0.21 --- --- --- 28 49 18 TOTAL 944 --- 17.51 299.7 --- 8.25 320.4 --- 116.94 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) APRIL MAY JUNE 1 52 94 24 94 13 3.3 24 3 0.21 2 20 28 2.3 173 272 270 26 4 0.25 3 8.0 7 0.14 101 115 36 39 13 2.2 4 6.2 7 0.11 84 26 6.8 96 125 59 5 379 867 2860 73 8 1.7 66 75 16 6 187 409 316 63 19 5.2 50 9 1.2 7 73 130 28 70 33 7.1 42 7 0.84 8 109 211 67 53 9 1.4 35 7 0.63 9 55 53 8.5 75 59 30 36 6 0.57 10 37 11 1.1 83 117 53 33 5 0.45 11 29 8 0.61 68 97 20 31 4 0.36 12 28 4 0.31 46 52 6.5 34 3 0.31 13 22 3 0.18 42 30 3.5 34 3 0.25 14 20 3 0.16 42 13 1.5 30 2 0.16 15 22 3 0.18 40 10 1.1 24 1 0.08 16 53 100 23 40 9 0.92 26 2 0.14 17 64 109 44 42 7 0.80 27 3 0.24 18 69 130 52 30 5 0.44 30 5 0.37 19 66 128 34 27 5 0.35 28 5 0.37 20 373 287 482 27 4 0.32 30 5 0.41 21 377 162 211 28 4 0.31 22 8 0.45 22 112 35 11 26 4 0.26 18 14 0.69 23 556 755 2920 25 3 0.24 18 10 0.47 24 526 552 1240 24 3 0.20 22 6 0.34 25 508 853 1540 24 3 0.18 22 2 0.12 26 502 878 1970 23 3 0.16 33 36 5.6 27 379 671 872 23 2 0.14 29 10 0.88 28 284 136 178 23 2 0.13 25 1 0.07 29 147 14 5.8 23 2 0.14 20 1 0.05 30 119 14 4.4 34 3 0.23 21 1 0.06 31 --- --- --- 33 3 0.26 --- --- --- TOTAL 5182.2 --- 12895.79 1559 --- 452.18 971 --- 92.77 85 RIO GRANDE DE ARECIBO BASIN 50021700 RIO GRANDE DE ARECIBO ABOVE UTUADO, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) JULY AUGUST SEPTEMBER 1 23 1 0.06 20 23 1.5 74 134 30 2 20 2 0.09 13 9 0.31 171 332 351 3 17 20 0.90 12 7 0.24 363 642 1410 4 15 19 0.79 16 15 0.91 213 482 383 5 14 7 0.26 30 33 5.9 82 319 89 6 17 3 0.14 34 57 6.1 35 19 1.8 7 30 36 3.2 17 25 1.2 34 16 1.5 8 22 24 1.4 31 19 1.6 30 15 1.3 9 33 46 6.8 22 17 0.97 27 15 1.1 10 20 24 1.3 22 16 0.97 26 15 1.1 11 29 46 6.8 32 44 5.7 38 44 5.5 12 31 46 5.7 27 40 3.0 26 9 0.61 13 18 25 1.2 24 34 4.0 138 218 313 14 16 21 0.93 41 73 10 84 128 50 15 31 37 3.6 26 45 3.3 93 141 80 16 23 18 1.1 25 40 3.6 133 264 100 17 20 17 0.92 18 21 1.1 58 96 16 18 17 17 0.75 55 91 24 89 135 61 19 15 16 0.67 44 61 10 89 168 78 20 17 16 0.73 40 47 11 39 9 1.1 21 16 15 0.68 24 8 0.55 36 2 0.20 22 24 35 3.0 52 72 21 34 3 0.28 23 27 34 2.7 29 73 5.8 30 4 0.35 24 22 14 0.84 26 54 3.8 30 6 0.46 25 18 13 0.64 24 36 2.3 36 5 0.49 26 15 12 0.49 31 19 1.6 30 4 0.31 27 18 10 0.47 70 109 35 28 2 0.18 28 42 48 9.8 53 81 28 24 1 0.08 29 32 32 3.4 50 82 16 16 1 0.04 30 21 8 0.45 58 86 42 13 1 0.04 31 73 102 29 93 288 95 --- --- --- TOTAL 736 --- 88.81 1059 --- 346.45 2119 --- 2977.44 YEAR 20986.3 28296.60 e Estimated WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT Sus- Suspnd. pended Sus- sedi- Instan- sedi- pended ment, taneous ment sedi- sieve dis- concen- ment diametr Date Time charge, tration load, percent cfs mg/L tons/d <.063mm (00061) (80154) (80155) (70331) SEP 05... 0640 91 494 121 100 86 RIO GRANDE DE ARECIBO BASIN 50021700 RIO GRANDE DE ARECIBO ABOVE UTUADO, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 PARTICLE SIZE DISTRIBUTION OF SUSPENDED SEDIMENT Sus- Suspnd. Suspnd. Suspnd. Suspnd. Suspnd. Suspnd. Suspnd. Suspnd. Suspnd. pended Sus- sedi- sedi- sedi- sedi- sedi- sedi- sedi- sedi- sedi- Instan- sedi- pended ment, ment, ment, ment, ment, ment, ment, ment, ment, taneous ment sedi- falldia falldia falldia falldia falldia sieve sieve sieve sieve dis- concen- ment nat wat nat wat nat wat nat wat nat wat diametr diametr diametr diametr Date Time charge, tration load, percent percent percent percent percent percent percent percent percent cfs mg/L tons/d <.002mm <.004mm <.008mm <.016mm <.031mm <.063mm <.125mm <.25mm <.5 mm (00061) (80154) (80155) (70326) (70327) (70328) (70329) (70330) (70331) (70332) (70333) (70334) DEC 17... 2045 875 1640 3870 52 65 82 86 94 96 98 99 99 Suspnd. sedi- ment, sieve diametr Date percent <1 mm (70335) DEC 17... 100 87 RIO GRANDE DE ARECIBO BASIN 50022810 RIO VIVI BELOW HACIENDA EL PROGRESO, PR LOCATION.--Lat 18°11'21", long 66°40'20", Hydrologic Unit 21010001, 4.05 mi (6.52 km) east from Lago Adjuntas Dam, 2.90 mi (4.66 km) south of Lago Viví Dam, 3.80 mi (6.11 km) northeast from Adjuntas Plaza, 2.76 mi (4.44 km) northwest from Escuela de San Patricio. DRAINAGE AREA.--2.99 mi2 (7.74 km2). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--December 2000 to current year. GAGE.--Water-stage recorder and crest-stage gage. Elevation of gage is 1,710 ft (521 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 2001 TO SEPTEMBER 2002 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 e9.0 e9.8 8.1 7.8 3.9 2.8 3.1 11 5.0 e3.1 e3.7 e5.6 2 e8.5 e19 8.0 7.6 3.8 2.7 3.4 15 4.8 e3.2 e5.5 e11 3 e8.7 e12 18 7.3 4.1 2.6 e2.9 10 5.5 e3.1 4.1 e9.8 4 e8.9 e9.9 9.1 7.1 3.9 2.6 e2.6 11 14 e3.1 3.5 e7.9 5 e9.3 e14 8.3 8.4 3.7 2.5 e15 8.9 9.9 e3.0 3.5 e5.9 6 e7.7 e23 8.2 9.0 3.6 2.5 e19 8.2 e6.6 e7.8 3.4 e4.6 7 e7.4 e10 8.7 7.0 3.6 2.5 e7.2 8.8 e5.3 e8.0 3.5 e4.3 8 e7.4 85 8.1 6.6 3.5 2.6 e6.0 7.7 4.8 e4.2 4.0 e4.3 9 e7.5 36 8.0 6.4 3.5 2.5 e5.2 7.4 4.6 e3.8 4.3 e4.0 10 e18 22 8.0 6.1 3.4 2.6 e4.5 8.9 4.4 e3.8 5.1 e4.1 11 e8.3 23 34 6.0 3.3 10 e4.4 7.4 4.3 e3.4 6.6 e4.2 12 e7.5 18 13 5.8 3.2 3.9 e4.1 6.8 4.6 e3.3 4.8 e4.5 13 e6.9 51 11 5.7 3.2 2.7 e3.4 6.6 4.2 e3.4 5.3 e3.9 14 e6.6 20 9.6 5.6 3.1 2.5 e3.3 6.4 4.0 e3.3 5.2 e3.6 15 e9.2 24 9.3 5.4 3.0 2.5 e4.0 6.2 4.0 e4.3 3.9 e5.1 16 e6.8 14 21 5.4 3.0 4.9 5.0 6.5 3.9 e3.0 4.1 e8.9 17 e7.0 12 52 5.2 2.9 3.5 7.3 6.2 4.1 e3.0 3.7 e4.7 18 e6.9 11 e14 5.0 3.3 2.6 14 6.0 4.3 e3.0 e6.4 e7.4 19 e6.6 11 11 4.9 8.9 2.6 7.5 5.8 4.5 e2.9 4.5 e5.5 20 e6.3 10 8.5 4.8 3.7 2.3 42 5.6 3.9 e2.4 3.9 e4.3 21 e6.7 9.4 79 4.7 3.2 2.3 21 5.5 3.7 e2.7 e3.5 e4.0 22 e13 8.9 25 4.8 3.0 2.2 10 5.4 3.8 e3.2 e4.8 e3.8 23 e16 8.9 21 4.5 2.9 2.2 16 5.3 3.7 e4.5 e4.4 e3.6 24 e10 11 14 4.5 2.9 2.1 49 5.2 3.7 e3.0 5.5 e3.7 25 e8.2 8.8 12 4.3 2.9 2.1 61 5.1 3.7 e2.7 4.4 e4.6 26 e8.1 8.6 11 4.2 3.2 2.1 69 5.0 3.9 e2.6 3.7 e4.0 27 e13 8.6 10 4.2 2.9 2.1 44 5.2 4.0 e2.6 3.5 3.4 28 e26 8.3 9.3 4.2 2.7 2.1 26 5.0 e3.9 e6.2 26 3.5 29 e27 9.6 9.0 4.1 --- 9.5 18 5.0 e3.3 e5.4 e5.9 3.4 30 e14 8.4 8.5 3.9 --- 3.5 14 5.1 e3.2 e2.9 e7.2 3.3 31 e11 --- 8.1 4.0 --- 4.5 --- 4.9 --- e3.5 e8.1 --- TOTAL 317.5 525.2 482.8 174.5 98.3 98.1 491.9 217.1 143.6 114.4 166.0 150.9 MEAN 10.2 17.5 15.6 5.63 3.51 3.16 16.4 7.00 4.79 3.69 5.35 5.03 MAX 27 85 79 9.0 8.9 10 69 15 14 8.0 26 11 MIN 6.3 8.3 8.0 3.9 2.7 2.1 2.6 4.9 3.2 2.4 3.4 3.3 AC-FT 630 1040 958 346 195 195 976 431 285 227 329 299 CFSM 3.43 5.86 5.21 1.88 1.17 1.06 5.48 2.34 1.60 1.23 1.79 1.68 IN. 3.95 6.53 6.01 2.17 1.22 1.22 6.12 2.70 1.79 1.42 2.07 1.88 STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 2001 - 2002, BY WATER YEAR (WY) MEAN 10.2 17.5 15.6 4.37 2.98 2.81 9.75 8.91 4.72 6.75 7.02 11.9 MAX 10.2 17.5 15.6 5.63 3.51 3.16 16.4 10.8 4.79 9.80 8.69 18.8 (WY) 2002 2002 2002 2002 2002 2002 2002 2001 2002 2001 2001 2001 MIN 10.2 17.5 15.6 3.12 2.45 2.45 3.10 7.00 4.66 3.69 5.35 5.03 (WY) 2002 2002 2002 2001 2001 2001 2001 2002 2001 2002 2002 2002 SUMMARY STATISTICS FOR 2001 CALENDAR YEAR FOR 2002 WATER YEAR WATER YEARS 2001 - 2002 ANNUAL TOTAL 3270.8 2980.3 ANNUAL MEAN 8.96 8.17 8.17 HIGHEST ANNUAL MEAN 8.17 2002 LOWEST ANNUAL MEAN 8.17 2002 HIGHEST DAILY MEAN 108 May 6 85 Nov 8 108 May 6 2001 LOWEST DAILY MEAN 1.6 Mar 17 2.1 Mar 24 1.6 Mar 17 2001 ANNUAL SEVEN-DAY MINIMUM 1.7 Mar 13 2.1 Mar 22 1.7 Mar 13 2001 MAXIMUM PEAK FLOW 1150 Dec 21 1150 Dec 21 2001 MAXIMUM PEAK STAGE 6.51 Dec 21 6.51 Dec 21 2001 INSTANTANEOUS LOW FLOW 1.9 Mar 27 1.6 Mar 17 2001 ANNUAL RUNOFF (AC-FT) 6490 5910 5920 ANNUAL RUNOFF (CFSM) 3.00 2.73 2.73 ANNUAL RUNOFF (INCHES) 40.69 37.08 37.10 10 PERCENT EXCEEDS 18 14 14 50 PERCENT EXCEEDS 5.4 5.2 5.2 90 PERCENT EXCEEDS 2.1 2.9 2.9 e Estimated 88 RIO GRANDE DE ARECIBO BASIN 50022810 RIO VIVI BELOW HACIENDA EL PROGRESO,PR--Continued O N D 2001 J F M A M J J A S 2002 1 2 5 10 10 20 50 100 DISCHARGE, IN CUBIC FEET PER SECOND 89 RIO GRANDE DE ARECIBO BASIN 50022810 RIO VIVI BELOW HACIENDA EL PROGRESO, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--December 2000 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: December 2000 to current year. INSTRUMENTATION.-- USDH-48 and automatic sediment sampler since 2000. REMARKS.--Sediment samples were collected by a local observer on a weekly basis. During high flow events sediment samples were collected with automatic sediment sampler. EXTREMES OBSERVED FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATION: Maximum daily mean, 2,180 mg/L May 06, 2001; Minimum daily mean, 1 mg/L several days during Water Years 2001 and 2002. SEDIMENT LOADS: Maximum daily mean, 2,980 tons (2,703 tonnes) May 6, 2001; Minimum daily mean, <0.01 ton (<0.01 tonne) several days. EXTREMES OBSERVED FOR CURRENT YEAR 2002.-- SEDIMENT CONCENTRATION: Maximum daily mean, 1,220 mg/L December 21, 2001; Minimum daily mean, 1 mg/L several days. SEDIMENT LOADS: Maximum daily mean, 1,120 tons (1,016 tonnes) December 21, 2001; Minimum daily mean, <0.01 ton (<0.01 tonne) several days. SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) OCTOBER NOVEMBER DECEMBER 1 e9.0 e40 e0.99 e9.8 e42 e1.1 8.1 6 0.14 2 e8.5 e28 e0.64 e19 e221 e41 8.0 6 0.12 3 e8.7 e21 e0.49 e12 e61 e2.0 18 135 15 4 e8.9 e14 e0.33 e9.9 e46 e1.2 9.1 16 0.42 5 e9.3 e8 e0.19 e14 e67 e3.4 8.3 5 0.10 6 e7.7 e9 e0.19 e23 e238 e30 8.2 4 0.09 7 e7.4 e13 e0.27 e10 e51 e1.4 8.7 14 0.37 8 e7.4 e17 e0.34 85 866 414 8.1 36 0.77 9 e7.5 e18 e0.36 36 310 32 8.0 28 0.59 10 e18 e239 e44 22 139 8.5 8.0 20 0.44 11 e8.3 e11 e0.25 23 141 13 34 928 426 12 e7.5 e7 e0.14 18 33 1.6 13 14 0.52 13 e6.9 e7 e0.12 51 848 459 11 9 0.25 14 e6.6 e6 e0.11 20 44 2.6 9.6 8 0.20 15 e9.2 e61 e2.6 24 62 8.2 9.3 7 0.19 16 e6.8 e17 e0.32 14 7 0.26 21 180 28 17 e7.0 e15 e0.28 12 6 0.19 52 660 482 18 e6.9 e9 e0.17 11 5 0.16 e14 e84 e3.5 19 e6.6 e4 e0.08 11 5 0.14 11 42 1.2 20 e6.3 e3 e0.06 10 5 0.13 8.5 17 0.40 21 e6.7 e4 e0.07 9.4 7 0.18 79 1220 1120 22 e13 e92 e8.7 8.9 7 0.16 25 165 15 23 e16 e170 e20 8.9 7 0.17 21 76 6.9 24 e10 e31 e0.88 11 26 1.2 14 10 0.38 25 e8.2 e18 e0.41 8.8 5 0.13 12 7 0.23 26 e8.1 e16 e0.35 8.6 5 0.12 11 5 0.14 27 e13 e75 e4.9 8.6 5 0.12 10 3 0.07 28 e26 e435 e154 8.3 5 0.11 9.3 2 0.05 29 e27 e447 e128 9.6 13 0.36 9.0 2 0.05 30 e14 e71 e2.9 8.4 11 0.24 8.5 2 0.05 31 e11 e46 e1.3 --- --- --- 8.1 2 0.04 TOTAL 317.5 --- 373.44 525.2 --- 1022.67 482.8 --- 2103.21 90 RIO GRANDE DE ARECIBO BASIN 50022810 RIO VIVI BELOW HACIENDA EL PROGRESO, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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 FEBRUARY MARCH 1 7.8 2 0.04 3.9 5 0.06 2.8 5 0.04 2 7.6 1 0.03 3.8 5 0.06 2.7 6 0.04 3 7.3 1 0.03 4.1 6 0.06 2.6 6 0.05 4 7.1 5 0.10 3.9 6 0.06 2.6 7 0.05 5 8.4 5 0.12 3.7 6 0.06 2.5 6 0.04 6 9.0 3 0.08 3.6 6 0.06 2.5 5 0.03 7 7.0 1 0.03 3.6 6 0.06 2.5 3 0.02 8 6.6 3 0.05 3.5 6 0.06 2.6 3 0.02 9 6.4 4 0.07 3.5 7 0.06 2.5 3 0.02 10 6.1 6 0.09 3.4 7 0.07 2.6 3 0.02 11 6.0 5 0.09 3.3 8 0.07 10 97 8.7 12 5.8 5 0.07 3.2 7 0.06 3.9 9 0.11 13 5.7 4 0.06 3.2 5 0.05 2.7 7 0.05 14 5.6 3 0.05 3.1 5 0.04 2.5 14 0.09 15 5.4 3 0.04 3.0 5 0.04 2.5 20 0.14 16 5.4 2 0.03 3.0 4 0.03 4.9 40 0.87 17 5.2 5 0.08 2.9 3 0.03 3.5 12 0.13 18 5.0 5 0.07 3.3 2 0.02 2.6 4 0.03 19 4.9 4 0.05 8.9 56 2.5 2.6 2 0.02 20 4.8 2 0.03 3.7 4 0.04 2.3 2 0.01 21 4.7 2 0.02 3.2 2 0.02 2.3 1 <0.01 22 4.8 5 0.07 3.0 2 0.02 2.2 1 <0.01 23 4.5 11 0.13 2.9 3 0.02 2.2 1 <0.01 24 4.5 16 0.19 2.9 4 0.03 2.1 2 <0.01 25 4.3 15 0.18 2.9 5 0.04 2.1 2 0.01 26 4.2 13 0.14 3.2 5 0.04 2.1 2 <0.01 27 4.2 10 0.11 2.9 5 0.04 2.1 1 <0.01 28 4.2 8 0.09 2.7 5 0.04 2.1 1 <0.01 29 4.1 6 0.07 --- --- --- 9.5 64 5.6 30 3.9 6 0.06 --- --- --- 3.5 4 0.05 31 4.0 5 0.06 --- --- --- 4.5 14 0.40 TOTAL 174.5 --- 2.33 98.3 --- 3.74 98.1 --- 16.61 < Actual value is known to be less than the value shown MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) APRIL MAY JUNE 1 3.1 11 0.10 11 11 0.33 5.0 5 0.06 2 3.4 9 0.08 15 55 4.5 4.8 4 0.06 3 e2.9 e8 e0.06 10 11 0.30 5.5 4 0.06 4 e2.6 e7 e0.05 11 13 0.38 14 989 107 5 e15 e151 e24 8.9 15 0.36 9.9 62 2.5 6 e19 e220 e32 8.2 17 0.39 e6.6 e17 e0.29 7 e7.2 e8 e0.18 8.8 19 0.46 e5.3 e10 e0.14 8 e6.0 e3 e0.06 7.7 21 0.43 4.8 8 0.10 9 e5.2 e5 e0.06 7.4 22 0.44 4.6 8 0.10 10 e4.5 e7 e0.08 8.9 28 0.97 4.4 10 0.12 11 e4.4 e9 e0.10 7.4 13 0.26 4.3 11 0.13 12 e4.1 e11 e0.12 6.8 12 0.22 4.6 7 0.09 13 e3.4 e14 e0.13 6.6 10 0.19 4.2 4 0.04 14 e3.3 e17 e0.15 6.4 9 0.16 4.0 3 0.03 15 e4.0 e19 e0.21 6.2 8 0.13 4.0 3 0.03 16 5.0 16 0.21 6.5 6 0.11 3.9 2 0.02 17 7.3 38 1.5 6.2 5 0.09 4.1 2 0.02 18 14 221 40 6.0 4 0.07 4.3 2 0.03 19 7.5 53 1.1 5.8 3 0.05 4.5 3 0.03 20 42 683 139 5.6 2 0.03 3.9 3 0.03 21 21 204 20 5.5 2 0.03 3.7 3 0.03 22 10 23 0.68 5.4 2 0.03 3.8 4 0.04 23 16 111 9.6 5.3 2 0.03 3.7 4 0.04 24 49 721 386 5.2 3 0.04 3.7 5 0.05 25 61 772 387 5.1 4 0.06 3.7 6 0.06 26 69 1070 929 5.0 6 0.07 3.9 7 0.08 27 44 626 158 5.2 7 0.09 4.0 9 0.09 28 26 123 10 5.0 6 0.07 e3.9 e9 e0.09 29 18 12 0.58 5.0 4 0.05 e3.3 e6 e0.06 30 14 11 0.42 5.1 3 0.05 e3.2 e6 e0.06 31 --- --- --- 4.9 5 0.06 --- --- --- TOTAL 491.9 --- 2140.47 217.1 --- 10.45 143.6 --- 111.48 91 RIO GRANDE DE ARECIBO BASIN 50022810 RIO VIVI BELOW HACIENDA EL PROGRESO, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) JULY AUGUST SEPTEMBER 1 e3.1 e5 e0.04 e3.7 e4 e0.03 e5.6 e12 e0.25 2 e3.2 e5 e0.04 e5.5 e5 e0.04 e11 e13 e0.38 3 e3.1 e5 e0.04 4.1 4 0.04 e9.8 e11 e0.30 4 e3.1 e5 e0.04 3.5 3 0.03 e7.9 e13 e0.26 5 e3.0 e5 e0.04 3.5 2 0.02 e5.9 e3 e0.05 6 e7.8 e21 e0.43 3.4 4 0.03 e4.6 e8 e0.10 7 e8.0 e17 e0.39 3.5 6 0.05 e4.3 e11 e0.15 8 e4.2 e4 e0.04 4.0 7 0.08 e4.3 e11 e0.15 9 e3.8 e3 e0.03 4.3 11 0.15 e4.0 e4 e0.04 10 e3.8 e3 e0.03 5.1 13 0.24 e4.1 e4 e0.04 11 e3.4 e7 e0.07 6.6 21 0.54 e4.2 e4 e0.04 12 e3.3 e7 e0.07 4.8 11 0.16 e4.5 e11 e0.15 13 e3.4 e7 e0.07 5.3 12 0.25 e3.9 e11 e0.15 14 e3.3 e7 e0.07 5.2 5 0.07 e3.6 e3 e0.03 15 e4.3 e4 e0.04 3.9 4 0.05 e5.1 e13 e0.24 16 e3.0 e5 e0.04 4.1 4 0.04 e8.9 e19 e0.46 17 e3.0 e5 e0.04 3.7 3 0.03 e4.7 e8 e0.10 18 e3.0 e5 e0.04 e6.4 e30 e1.1 e7.4 e13 e0.26 19 e2.9 e6 e0.04 4.5 8 0.10 e5.5 e27 e0.66 20 e2.4 e6 e0.04 3.9 3 0.03 e4.3 e11 e0.15 21 e2.7 e6 e0.04 e3.5 e2 e0.02 e4.0 e4 e0.04 22 e3.2 e5 e0.04 e4.8 e1 e0.01 e3.8 e4 e0.05 23 e4.5 e4 e0.04 e4.4 e1 e0.01 e3.6 e3 e0.03 24 e3.0 e5 e0.04 5.5 27 0.66 e3.7 e3 e0.03 25 e2.7 e6 e0.04 4.4 6 0.08 e4.6 e11 e0.16 26 e2.6 e6 e0.04 3.7 2 0.02 e4.0 e20 e0.18 27 e2.6 e6 e0.04 3.5 2 0.02 3.4 19 0.17 28 e6.2 e21 e0.54 26 390 183 3.5 16 0.15 29 e5.4 e12 e0.25 e5.9 e37 e0.54 3.4 13 0.12 30 e2.9 e5 e0.04 e7.2 e37 e0.75 3.3 10 0.09 31 e3.5 e6 e0.06 e8.1 e39 e0.79 --- --- --- TOTAL 114.4 --- 2.81 166.0 --- 188.98 150.9 --- 4.98 YEAR 2980.3 5981.17 e Estimated WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT Sus- Suspnd. pended Sus- sedi- Instan- sedi- pended ment, taneous ment sedi- sieve dis- concen- ment diametr Date Time charge, tration load, percent cfs mg/L tons/d <.063mm (00061) (80154) (80155) (70331) OCT 28... 1630 234 5570 3520 98 DEC 21... 1645 563 4630 7040 88 92 RIO GRANDE DE ARECIBO BASIN 50024950 RIO GRANDE DE ARECIBO BELOW UTUADO, PR LOCATION.--Lat 18°18'07", long 66°42'15", Hydrologic Unit 21010001, 2.4 mi (3.9 km) north of Utuado Plaza, 3.4 mi (5.5 km) southwest from Lago Dos Bocas Dam, 3.5 mi (5.6 km) northwest from Lago Caonillas Dam. DRAINAGE AREA.--65.6 mi2 (170 km2). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--April 1996 to September 1998, June 1999 to current year. GAGE.--Water-stage recorder. Elevation of gage is 295.28 ft (90 m), from topographic map. REMARKS.--Records poor. Gage-height and precipitation satellite telemetry at station. Discharge, cubic feet per second WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 105 139 106 93 54 41 229 362 64 e58 186 e96 2 100 150 111 95 52 40 167 470 62 e58 146 e877 3 116 176 192 96 51 38 77 379 74 e48 104 659 4 104 110 196 94 55 38 57 e285 e170 e47 195 559 5 96 115 130 99 54 35 480 244 e155 e42 115 398 6 102 154 103 e98 51 34 598 202 e119 e87 132 260 7 99 213 95 99 51 33 457 198 e94 e82 72 216 8 128 2390 84 99 50 e44 650 165 e79 e62 87 178 9 100 864 77 95 48 e37 383 235 e77 e168 99 153 10 395 446 83 84 48 e53 258 238 e70 e77 143 193 11 282 307 181 83 47 159 204 217 e67 e123 203 204 12 148 277 168 80 57 128 177 156 e73 e283 156 e130 13 126 248 110 80 43 60 151 136 e79 91 85 e194 14 110 324 86 81 41 47 136 125 e64 61 145 229 15 118 266 75 79 40 42 135 153 e56 70 108 e145 16 110 204 137 74 41 50 278 275 e54 62 75 e200 17 105 176 293 73 41 59 222 178 e59 60 65 159 18 93 159 262 68 42 42 319 128 e69 57 119 430 19 89 150 176 64 97 41 482 111 e63 51 136 441 20 76 142 154 62 71 e37 687 104 e69 61 121 222 21 73 137 223 60 53 e34 687 98 e61 60 83 146 22 171 123 191 60 49 31 360 93 e48 122 253 119 23 236 123 197 63 47 28 767 90 e45 91 167 98 24 176 140 166 65 45 26 865 86 e50 67 172 111 25 111 121 133 61 43 26 1210 81 e63 58 134 111 26 91 119 121 60 46 26 853 78 e79 47 127 91 27 239 114 109 59 46 25 934 77 e83 48 159 81 28 275 115 103 59 42 39 680 77 e69 148 120 72 29 274 141 100 60 --- 49 717 65 e59 e140 172 60 30 210 124 96 55 --- 109 490 74 e54 e68 118 e58 31 145 --- 94 54 --- 107 --- 76 --- 171 204 --- TOTAL 4603 8267 4352 2352 1405 1558 13710 5256 2228 2668 4201 6890 MEAN 148 276 140 75.9 50.2 50.3 457 170 74.3 86.1 136 230 MAX 395 2390 293 99 97 159 1210 470 170 283 253 877 MIN 73 110 75 54 40 25 57 65 45 42 65 58 AC-FT 9130 16400 8630 4670 2790 3090 27190 10430 4420 5290 8330 13670 CFSM 2.26 4.20 2.14 1.16 0.76 0.77 6.96 2.58 1.13 1.31 2.07 3.50 IN. 2.61 4.69 2.47 1.33 0.80 0.88 7.77 2.98 1.26 1.51 2.38 3.91 STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1996 - 2002, BY WATER YEAR (WY) MEAN 280 308 130 92.3 66.2 53.2 145 158 91.6 101 175 413 MAX 490 766 242 166 102 76.7 457 249 130 184 393 1100 (WY) 2000 2000 2000 2000 2000 2000 2002 2000 2000 1998 1998 1998 MIN 148 84.8 53.0 39.5 46.6 33.8 46.2 50.8 40.8 36.6 77.0 87.3 (WY) 2002 1998 1998 1998 1998 1998 1997 1997 1997 1997 1997 1997 SUMMARY STATISTICS FOR 2001 CALENDAR YEAR FOR 2002 WATER YEAR WATER YEARS 1996 - 2002 ANNUAL TOTAL 44968 57490 ANNUAL MEAN 123 158 164 HIGHEST ANNUAL MEAN 233 2000 LOWEST ANNUAL MEAN 99.6 1997 HIGHEST DAILY MEAN 2390 Nov 8 2390 Nov 8 17900 Sep 22 1998 LOWEST DAILY MEAN 25 Apr 19 25 Mar 27 22 Mar 20 1998 ANNUAL SEVEN-DAY MINIMUM 28 Apr 14 28 Mar 21 23 Mar 19 1998 MAXIMUM PEAK FLOW 7000 Nov 8 76400 Sep 22 1998 MAXIMUM PEAK STAGE 12.14 Nov 8 32.92 Sep 22 1998 INSTANTANEOUS LOW FLOW 23 Mar 24 13 Jul 3 2002 ANNUAL RUNOFF (AC-FT) 89190 114000 119000 ANNUAL RUNOFF (CFSM) 1.88 2.40 2.50 ANNUAL RUNOFF (INCHES) 25.49 32.59 34.01 10 PERCENT EXCEEDS 220 282 326 50 PERCENT EXCEEDS 87 102 87 90 PERCENT EXCEEDS 35 47 39 e Estimated 93 RIO GRANDE DE ARECIBO BASIN 50024950 RIO GRANDE DE ARECIBO BELOW UTUADO, PR--Continued O N D 2001 J F M A M J J A S 2002 10 20 50 100 100 200 500 1000 1000 2000 5000 10,000 DISCHARGE, IN CUBIC FEET PER SECOND 94 RIO GRANDE DE ARECIBO BASIN 50024950 RIO GRANDE DE ARECIBO BELOW UTUADO, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORDS.--April 1996 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: April 1996 to current year. INSTRUMENTATION.--USDH-48 and automatic sediment samplers since 1996. REMARKS.-- Sediment samples were collected by a local observer on a weekly basis. During high flow events sediment samples were collected with automatic sediment sampler. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATION: Maximum daily mean, 10,600 mg/L September 10, 1996; Minimum daily mean, 3 mg/L August 6, 1996. SEDIMENT LOADS: Maximum daily mean, e768,000 tons (e698,000 tonnes) September 22,1998; Minimum daily mean, 0.50 ton (0.45 tonne) August 6, 1996. EXTREMES FOR CURRENT YEAR 2002.-- SEDIMENT CONCENTRATION: Maximum daily mean, 6,000 mg/L November 8, 2001; Minimum daily mean, 6 mg/L May 7, 8, 2002. SEDIMENT LOADS: Maximum daily mean, 59,800 tons (54,250 tonnes) November 8, 2001; Minimum daily mean, .85 ton (.77 tonne) March 27, 2002. SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) OCTOBER NOVEMBER DECEMBER 1 105 54 15 139 118 56 106 45 13 2 100 52 14 150 140 117 111 42 12 3 116 82 30 176 306 151 192 176 172 4 104 37 10 110 305 91 196 151 92 5 96 35 9.0 115 326 101 130 108 40 6 102 28 7.8 154 342 142 103 79 22 7 99 22 5.8 213 469 425 95 74 19 8 128 61 30 2390 6000 59800 84 65 15 9 100 16 4.4 864 1610 4040 77 55 11 10 395 588 1760 446 616 778 83 46 10 11 282 345 313 307 188 158 181 233 284 12 148 97 40 277 113 85 168 264 127 13 126 86 30 248 163 136 110 149 45 14 110 64 19 324 336 457 86 96 22 15 118 86 35 266 221 170 75 91 18 16 110 67 21 204 78 43 137 164 112 17 105 62 20 176 61 29 293 399 750 18 93 52 14 159 45 19 262 245 206 19 89 34 8.3 150 31 12 176 96 46 20 76 32 6.5 142 31 12 154 100 43 21 73 31 6.1 137 32 12 223 250 291 22 171 214 374 123 34 11 191 163 96 23 236 439 388 123 35 12 197 154 89 24 176 174 98 140 35 13 166 107 49 25 111 77 24 121 36 12 133 75 27 26 91 60 15 119 36 12 121 59 19 27 239 333 724 114 36 11 109 43 13 28 275 373 505 115 35 11 103 30 8.4 29 274 309 287 141 91 37 100 31 8.3 30 210 231 138 124 55 19 96 33 8.6 31 145 123 51 --- --- --- 94 36 9.0 TOTAL 4603 --- 5002.9 8267 --- 66972 4352 --- 2677.3 95 RIO GRANDE DE ARECIBO BASIN 50024950 RIO GRANDE DE ARECIBO BELOW UTUADO, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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 FEBRUARY MARCH 1 93 36 9.0 54 25 3.7 41 24 2.7 2 95 36 9.1 52 23 3.3 40 23 2.5 3 96 35 9.1 51 21 2.9 38 22 2.3 4 94 35 8.9 55 19 2.8 38 21 2.1 5 99 35 9.3 54 17 2.5 35 19 1.8 6 e98 e35 e9.1 51 15 2.1 34 18 1.6 7 99 34 9.1 51 14 1.9 33 17 1.5 8 99 52 15 50 12 1.6 e44 e24 e3.6 9 95 71 18 48 12 1.5 e37 e18 e2.0 10 84 62 14 48 12 1.6 e53 e28 e4.7 11 83 57 13 47 12 1.5 159 182 185 12 80 49 11 57 50 9.1 128 104 43 13 80 41 8.8 43 12 1.4 60 27 4.5 14 81 33 7.2 41 11 1.2 47 13 1.7 15 79 28 5.8 40 12 1.3 42 11 1.3 16 74 32 6.4 41 16 1.7 50 26 4.7 17 73 35 6.9 41 20 2.2 59 33 5.3 18 68 27 5.0 42 23 2.6 42 21 2.4 19 64 24 4.1 97 79 23 41 17 1.8 20 62 21 3.5 71 48 9.7 e37 e16 e1.6 21 60 20 3.2 53 30 4.3 e34 e16 e1.4 22 60 22 3.5 49 28 3.7 31 15 1.3 23 63 24 4.1 47 23 2.9 28 15 1.1 24 65 26 4.6 45 17 2.1 26 14 1.0 25 61 28 4.6 43 12 1.4 26 14 0.95 26 60 29 4.7 46 8 0.93 26 13 0.91 27 59 30 4.7 46 12 1.5 25 13 0.85 28 59 30 4.8 42 19 2.2 39 21 3.1 29 60 31 4.9 --- --- --- 49 36 7.2 30 55 29 4.3 --- --- --- 109 85 36 31 54 27 3.9 --- --- --- 107 94 74 TOTAL 2352 --- 229.6 1405 --- 96.63 1558 --- 403.91 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) APRIL MAY JUNE 1 229 231 233 362 116 128 64 60 10 2 167 136 88 470 580 1420 62 54 9.0 3 77 12 2.6 379 280 304 74 48 9.4 4 57 10 1.5 e285 e152 e116 e170 e435 e277 5 480 1910 10100 244 98 65 e155 e299 e149 6 598 867 1630 202 34 19 e119 e40 e13 7 457 422 600 198 6 3.5 e94 e35 e9.0 8 650 640 1410 165 6 2.6 e79 e30 e6.4 9 383 79 82 235 188 303 e77 e25 e5.1 10 258 84 58 238 191 137 e70 e20 e3.9 11 204 93 51 217 178 118 e67 e20 e3.6 12 177 93 45 156 75 32 e73 e20 e3.9 13 151 67 28 136 42 15 e79 e19 e4.1 14 136 39 14 125 36 12 e64 e19 e3.3 15 135 16 5.8 153 119 80 e56 e19 e2.9 16 278 337 491 275 566 974 e54 e22 e3.2 17 222 179 120 178 151 75 e59 e25 e3.9 18 319 375 428 128 40 14 e69 e27 e5.0 19 482 779 1390 111 35 11 e63 e23 e4.0 20 687 1220 3100 104 32 8.8 e69 e17 e3.2 21 687 1220 2540 98 28 7.4 e61 e13 e2.1 22 360 372 375 93 24 6.0 e48 e15 e1.9 23 767 1900 9340 90 20 5.0 e45 e17 e2.0 24 865 1440 4250 86 22 5.0 e50 e19 e2.5 25 1210 2210 13000 81 45 9.8 e63 e33 e7.3 26 853 921 3270 78 71 15 e79 e55 e15 27 934 1390 5470 77 90 19 e83 e37 e8.4 28 680 744 1750 77 86 18 e69 e26 e4.9 29 717 1730 7730 65 79 14 e59 e22 e3.3 30 490 184 259 74 73 15 e54 e17 e2.5 31 --- --- --- 76 67 14 --- --- --- TOTAL 13710 --- 67861.9 5256 --- 3966.1 2228 --- 578.8 96 RIO GRANDE DE ARECIBO BASIN 50024950 RIO GRANDE DE ARECIBO BELOW UTUADO, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) JULY AUGUST SEPTEMBER 1 e58 e20 e3.1 186 196 132 e96 e78 e27 2 e58 e25 e3.9 146 131 73 e877 e953 e3940 3 e48 e26 e3.4 104 51 16 659 1220 3210 4 e47 e27 e3.4 195 201 213 559 689 1170 5 e42 e28 e3.2 115 45 16 398 404 469 6 e87 e102 e44 132 108 43 260 72 52 7 e82 e57 e13 72 27 5.4 216 30 18 8 e62 e49 e12 87 15 3.5 178 22 10 9 e168 e261 e432 99 54 21 153 18 7.6 10 e77 e59 e14 143 488 332 193 196 157 11 e123 e168 e175 203 491 358 204 211 134 12 e283 e492 e1470 156 137 64 e130 e81 e29 13 91 81 22 85 61 14 e194 e189 e217 14 61 40 6.6 145 145 59 229 258 206 15 70 46 9.0 108 83 27 e145 e102 e45 16 62 35 5.9 75 42 9.2 e200 e268 e182 17 60 30 4.8 65 33 6.5 159 122 55 18 57 26 4.0 119 98 61 430 794 2890 19 51 22 3.0 136 115 51 441 868 2280 20 61 29 5.9 121 104 62 222 210 132 21 60 32 5.3 83 54 13 146 52 21 22 122 114 72 253 393 743 119 33 11 23 91 79 20 167 152 76 98 32 8.5 24 67 31 5.7 172 171 123 111 30 9.1 25 58 21 3.3 134 107 40 111 29 8.6 26 47 15 1.9 127 98 34 91 26 6.5 27 48 14 1.9 159 137 73 81 24 5.2 28 148 150 134 120 87 51 72 21 4.2 29 e140 e77 e26 172 157 83 60 19 3.1 30 e68 e23 e3.7 118 90 33 e58 e17 e3.0 31 171 190 165 204 193 129 --- --- --- TOTAL 2668 --- 2677.0 4201 --- 2964.6 6890 --- 15310.8 YEAR 57490 168741.54 e Estimated WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT Sus- Suspnd. pended Sus- sedi- Instan- sedi- pended ment, taneous ment sedi- sieve dis- concen- ment diametr Date Time charge, tration load, percent cfs mg/L tons/d <.062mm (00061) (80154) (80155) (70331) APR 25... 1700 2900 12100 94400 89 SEP 10... 1850 326 1000 881 99 97 RIO GRANDE DE ARECIBO BASIN 50025000 RIO GRANDE DE ARECIBO NEAR UTUADO, PR WATER-QUALITY 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 Río de Caguana, and 2.5 mi (4.0 km) north of Utuado Plaza. DRAINAGE AREA.--66.0 mi2 (170.9 km2) this excludes 6.0 mi2 (15.5 km2) upstream from Lago Garzas to Río Guayanes in the Río Tallaboa basin. PERIOD OF RECORD.--Water years 1959-74, 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 TURBID- FECAL FECAL SPECIF. PH, ITY, DIS- COD, COLI- STREP- HARD- INSTAN- CONDUC- WATER, WAT UNF SOLVED HIGH FORM, TOCOCCI NESS, TANEOUS TANCE, UNFLTRD TEMPER- LAB, DIS- OXYGEN, LEVEL, M-FC KF WATER, CALCIUM DIS- WAT UNF FIELD, ATURE, HACH SOLVED PERCENT WATER, 0.7U MF MF, UNFLTRD WATER, DATE TIME CHARGE, US/CM STD WATER, 2100AN OXYGEN, OF SAT- UNFLTRD COL/ COL/ MG/L AS FLTRD, CFS 25 DEGC UNITS DEG C NTU MG/L URATION MG/L 100 ML 100 ML CACO3 MG/L (00061) (00095) (00400) (00010) (99872) (00300) (00301) (00340) (31625) (31673) (00900) (00915) DEC 13... 1330 127 250 7.4 25.4 33 8.1 100 <10 21000 520 93 25.2 FEB 21... 1110 54 295 7.5 22.3 13 8.2 96 <10 E955 310 -- -- SEP 05... 0830 -- 186 6.6 24.0 300 8.0 95 <10 E13000 E12000 75 20.3 ANC, RESIDUE RESIDUE WAT UNF WATER, TOTAL MAGNES- POTAS- FIXED CHLOR- FLUOR- FLTRD, AT 105 IUM, SODIUM, SODIUM SIUM, END PT, SULFIDE SULFATE IDE, IDE, SILICA, SUM OF RESIDUE DEG. C, WATER, WATER, ADSORP- WATER, FIELD, WATER WATER, WATER, WATER, WATER, CONSTI- WATER, SUS- DATE FLTRD, FLTRD, TION FLTRD, MG/L AS UNFLTRD FLTRD, FLTRD, FLTRD, FLTRD, TUENTS FLTRD, PENDED, MG/L MG/L RATIO MG/L CACO3 MG/L MG/L MG/L MG/L MG/L MG/L TONS/D MG/L (00925) (00930) (00931) (00935) (00410) (00745) (00945) (00940) (00950) (00955) (70301) (70302) (00530) DEC 13... 7.31 11.1 .5 2.31 79 <1.0 18.5 10.8 <.1 25.9 148 50.8 48 FEB 21... -- -- -- -- -- -- -- -- -- -- -- -- 20 SEP 05... 5.78 9.57 .5 2.03 62 <.1 15.6 8.27 E.10 23.0 122 -- 196 NITRITE AMMONIA CHROM- + + BARIUM, BORON, IUM, COPPER, IRON, LEAD, NITRITE NITRATE AMMONIA ORG-N, PHOS- WATER, WATER, WATER, WATER, WATER, WATER, WATER, WATER WATER, WATER, PHORUS, ARSENIC UNFLTRD UNFLTRD CADMIUM UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD WATER, WATER RECOV- RECOV- WATER, RECOV- RECOV- RECOV- RECOV- DATE MG/L MG/L MG/L MG/L UNFLTRD UNFLTRD ERABLE, ERABLE, UNFLTRD ERABLE, ERABLE, ERABLE, ERABLE, AS N AS N AS N AS N MG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L (00615) (00630) (00610) (00625) (00665) (01002) (01007) (01022) (01027) (01034) (01042) (01045) (01051) DEC 13... .02 1.10 .03 E.40 E.10 E1 47.1 E10 <.1 <.8 E10 1150 1 FEB 21... .05 1.50 .09 .30 .11 -- -- -- -- -- -- -- -- SEP 05... .04 .930 .04 .90 .22 <2 88.4 <20 <.1 2.8 20 5660 3 MANGAN- PHEN- ESE, MERCURY SILVER, ZINC, OLIC WATER, WATER, SELEN- WATER, WATER, COM- UNFLTRD UNFLTRD IUM, UNFLTRD UNFLTRD CYANIDE POUNDS, MBAS, RECOV- RECOV- WATER, RECOV- RECOV- WATER WATER, WATER, DATE ERABLE, ERABLE, UNFLTRD ERABLE, ERABLE, UNFLTRD UNFLTRD UNFLTRD UG/L UG/L UG/L UG/L UG/L MG/L UG/L MG/L (01055) (71900) (01147) (01077) (01092) (00720) (32730) (38260) DEC 13... 86.1 <.01 <2 <.3 <20 <.01 <16 <.05 FEB 21... -- -- -- -- -- -- -- -- SEP 05... 259 .02 <2 <.3 E30 <.01 <16 <.05 E -- Estimated value < -- Less than 98 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 Gripiñas. DRAINAGE AREA.--9.25 mi2 (24.0 km2). 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. Gage-height and precipitation satellite telemetry at station. Discharge, cubic feet per second WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 e23 19 17 18 11 9.7 20 81 19 13 e21 38 2 e22 76 45 17 10 9.8 26 91 15 13 e14 42 3 24 51 85 16 10 9.5 17 71 94 13 11 47 4 21 30 43 16 11 9.2 12 56 42 12 e12 38 5 22 33 29 25 10 9.0 36 48 274 12 18 24 6 20 64 24 30 9.7 8.7 37 43 121 20 13 18 7 18 51 22 21 9.8 8.6 25 40 74 16 11 15 8 18 487 20 18 9.6 9.3 39 36 48 12 11 13 9 22 179 19 17 9.5 9.5 58 32 38 23 9.5 13 10 e68 101 18 16 9.3 16 36 30 32 16 26 13 11 46 69 31 16 8.9 77 31 28 29 12 47 12 12 28 53 25 15 8.7 35 25 26 26 12 30 11 13 25 45 21 15 8.7 17 21 24 24 11 15 10 14 23 42 20 14 8.4 14 18 22 23 12 14 9.9 15 25 37 19 14 8.3 e12 20 21 21 13 11 13 16 22 33 21 13 8.1 54 30 24 20 11 12 34 17 25 30 24 13 8.0 34 25 20 20 10 10 13 18 25 28 29 13 10 18 77 19 20 10 10 29 19 e21 26 41 12 23 18 101 18 21 9.5 10 19 20 20 25 24 12 18 14 143 17 18 9.2 9.7 e13 21 18 23 120 12 12 13 132 16 17 9.0 8.9 e11 22 20 22 56 13 11 12 72 15 17 10 21 11 23 18 21 40 12 10 12 80 15 16 10 21 9.9 24 17 22 43 14 10 11 82 14 16 8.9 18 12 25 17 21 33 12 9.8 11 146 14 15 8.4 17 16 26 16 20 28 12 11 10 200 13 19 8.2 12 12 27 29 20 25 11 11 e10 214 14 17 8.4 10 e10 28 42 21 22 12 9.7 13 147 13 15 12 13 10 29 49 23 21 12 --- 140 166 13 14 11 15 9.9 30 26 19 19 11 --- 53 121 38 14 8.5 20 9.3 31 21 --- 18 11 --- 32 --- 25 --- 15 25 --- TOTAL 791 1691 1002 463 294.5 709.3 2157 937 1139 369.1 496.1 536.0 MEAN 25.5 56.4 32.3 14.9 10.5 22.9 71.9 30.2 38.0 11.9 16.0 17.9 MAX 68 487 120 30 23 140 214 91 274 23 47 47 MIN 16 19 17 11 8.0 8.6 12 13 14 8.2 8.9 9.3 AC-FT 1570 3350 1990 918 584 1410 4280 1860 2260 732 984 1060 CFSM 2.76 6.09 3.49 1.61 1.14 2.47 7.77 3.27 4.10 1.29 1.73 1.93 IN. 3.18 6.80 4.03 1.86 1.18 2.85 8.67 3.77 4.58 1.48 2.00 2.16 STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1989 - 2002, BY WATER YEAR (WY) MEAN 42.3 34.5 17.6 17.2 15.3 12.1 24.5 36.2 24.6 16.7 27.7 90.4 MAX 72.0 91.5 39.3 48.1 44.4 22.9 71.9 98.6 41.5 50.9 74.5 365 (WY) 1996 2000 2000 1992 1996 2002 2002 1995 1999 1996 1998 1996 MIN 11.6 10.0 5.41 4.13 4.67 4.79 5.95 5.35 5.30 2.83 9.82 10.8 (WY) 1992 1994 1998 1995 1994 1994 1994 1990 1997 1994 1994 1994 SUMMARY STATISTICS FOR 2001 CALENDAR YEAR FOR 2002 WATER YEAR WATER YEARS 1989 - 2002 ANNUAL TOTAL 9209.7 10585.0 ANNUAL MEAN 25.2 29.0 29.9 HIGHEST ANNUAL MEAN 64.0 1996 LOWEST ANNUAL MEAN 10.9 1994 HIGHEST DAILY MEAN 487 Nov 8 487 Nov 8 4700 Sep 10 1996 LOWEST DAILY MEAN 3.9 Mar 18 8.0 Feb 17 2.3 Jul 27 1994 ANNUAL SEVEN-DAY MINIMUM 4.1 Mar 14 8.4 Feb 11 2.5 Jul 23 1994 MAXIMUM PEAK FLOW 2140 Mar 29 18500 Sep 21 1998 MAXIMUM PEAK STAGE 9.81 Mar 29 20.00 Sep 21 1998 INSTANTANEOUS LOW FLOW 7.5 Feb 17 2.1 Jul 26 1994 ANNUAL RUNOFF (AC-FT) 18270 21000 21650 ANNUAL RUNOFF (CFSM) 2.73 3.14 3.23 ANNUAL RUNOFF (INCHES) 37.04 42.57 43.89 10 PERCENT EXCEEDS 50 53 56 50 PERCENT EXCEEDS 17 18 14 90 PERCENT EXCEEDS 5.7 9.9 5.1 e Estimated 99 RIO GRANDE DE ARECIBO BASIN 50025155 RIO SALIENTE AT COABEY NEAR JAYUYA, PR--Continued O N D 2001 J F M A M J J A S 2002 1 2 5 10 10 20 50 100 100 200 500 1000 DISCHARGE, IN CUBIC FEET PER SECOND 100 RIO GRANDE DE ARECIBO BASIN 50025155 RIO SALIENTE AT COABEY NEAR JAYUYA, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--October 1989 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: October 2000 to current year. INSTRUMENTATION.--USDH-48 and automatic sediment samplers since October 2000. REMARKS.--Sediment samples were collected by a local observer on a weekly basis. During high flow events sediment samples were collected with automatic sediment sampler. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATION: Maximum daily mean, 693 mg/L July 14, 2001; Minimum daily mean, 1 mg/L several days during water years 2001 and 2002. SEDIMENT LOADS: Maximum daily mean, 2,480 tons (2,250 tonnes) July 14, 2001; Minimum daily mean, 0.01 ton (0.01 tonne) March 19, 2001. EXTREMES FOR CURRENT YEAR 2002.-- SEDIMENT CONCENTRATION: Maximum daily mean, 681 mg/L November 11, 2001; Minimum daily mean, 1 mg/L several days during water years 2001 and 2002. SEDIMENT LOADS: Maximum daily mean, 1,250 tons (1,134 tonnes) November 8, 2001; Minimum daily mean, 0.03 ton (0.03 tonne) several days. SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) OCTOBER NOVEMBER DECEMBER 1 e23 e6 e0.33 19 1 0.07 17 5 0.23 2 e22 e6 e0.33 76 133 96 45 63 13 3 24 7 0.47 51 44 9.0 85 149 75 4 21 6 0.34 30 3 0.21 43 35 5.0 5 22 4 0.21 33 14 1.6 29 5 0.40 6 20 1 0.08 64 60 13 24 4 0.27 7 18 1 0.05 51 19 4.2 22 3 0.19 8 18 1 0.05 487 681 1250 20 3 0.15 9 22 1 0.06 179 178 94 19 3 0.13 10 e68 e276 e346 101 26 7.2 18 2 0.11 11 46 45 6.8 69 17 3.3 31 27 4.7 12 28 8 0.57 53 12 1.7 25 29 1.9 13 25 6 0.39 45 12 1.4 21 22 1.2 14 23 4 0.25 42 12 1.4 20 20 1.1 15 25 2 0.16 37 13 1.3 19 19 0.94 16 22 2 0.12 33 14 1.2 21 21 1.3 17 25 2 0.14 30 12 0.99 24 24 1.6 18 25 2 0.13 28 11 0.80 29 36 4.8 19 e21 e2 e0.13 26 9 0.63 41 53 7.5 20 20 5 0.26 25 7 0.48 24 25 1.6 21 18 8 0.40 23 6 0.35 120 282 301 22 20 8 0.39 22 4 0.23 56 76 13 23 18 6 0.28 21 3 0.16 40 4 0.44 24 17 4 0.18 22 8 0.49 43 4 0.46 25 17 2 0.11 21 15 0.87 33 4 0.35 26 16 2 0.09 20 21 1.1 28 4 0.30 27 29 25 3.4 20 18 0.99 25 4 0.26 28 42 56 18 21 15 0.84 22 4 0.24 29 49 72 26 23 12 0.70 21 4 0.25 30 26 13 0.99 19 8 0.43 19 5 0.25 31 21 2 0.10 --- --- --- 18 5 0.26 TOTAL 791 --- 406.81 1691 --- 1494.64 1002 --- 437.93 101 RIO GRANDE DE ARECIBO BASIN 50025155 RIO SALIENTE AT COABEY NEAR JAYUYA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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 FEBRUARY MARCH 1 18 6 0.27 11 3 0.09 9.7 3 0.08 2 17 6 0.28 10 3 0.08 9.8 3 0.08 3 16 7 0.32 10 3 0.09 9.5 3 0.08 4 16 8 0.36 11 3 0.10 9.2 3 0.07 5 25 10 0.66 10 3 0.09 9.0 3 0.07 6 30 8 0.64 9.7 4 0.09 8.7 3 0.07 7 21 5 0.28 9.8 4 0.10 8.6 3 0.07 8 18 3 0.13 9.6 4 0.10 9.3 3 0.08 9 17 4 0.20 9.5 4 0.10 9.5 3 0.08 10 16 7 0.29 9.3 4 0.09 16 51 4.0 11 16 9 0.36 8.9 4 0.08 77 219 118 12 15 8 0.32 8.7 3 0.08 35 55 7.4 13 15 7 0.27 8.7 3 0.07 17 15 0.67 14 14 4 0.17 8.4 3 0.07 14 10 0.38 15 14 2 0.08 8.3 3 0.07 e12 e7 e0.26 16 13 3 0.10 8.1 3 0.07 54 98 41 17 13 3 0.10 8.0 3 0.06 34 54 6.4 18 13 3 0.10 10 3 0.08 18 18 0.87 19 12 3 0.10 23 13 1.0 18 11 0.53 20 12 3 0.10 18 12 0.63 14 4 0.16 21 12 3 0.10 12 4 0.13 13 2 0.06 22 13 3 0.10 11 3 0.07 12 1 0.05 23 12 3 0.10 10 3 0.08 12 1 0.03 24 14 4 0.15 10 4 0.10 11 1 0.04 25 12 5 0.17 9.8 3 0.07 11 1 0.04 26 12 6 0.19 11 2 0.04 10 2 0.05 27 11 6 0.19 11 1 0.03 e10 e2 e0.05 28 12 7 0.21 9.7 3 0.08 13 2 0.07 29 12 7 0.21 --- --- --- 140 456 914 30 11 5 0.14 --- --- --- 53 87 17 31 11 3 0.09 --- --- --- 32 32 3.0 TOTAL 463 --- 6.78 294.5 --- 3.74 709.3 --- 1114.74 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) APRIL MAY JUNE 1 20 8 0.49 81 10 2.1 19 8 0.43 2 26 29 4.9 91 104 38 15 6 0.25 3 17 4 0.23 71 49 10 94 174 175 4 12 2 0.08 56 6 0.96 42 24 2.9 5 36 67 18 48 4 0.51 274 584 764 6 37 40 4.6 43 2 0.19 121 210 84 7 25 14 0.91 40 1 0.11 74 47 11 8 39 44 5.2 36 1 0.10 48 6 0.81 9 58 61 10 32 1 0.09 38 5 0.48 10 36 16 1.6 30 1 0.08 32 3 0.30 11 31 9 0.78 28 1 0.07 29 2 0.17 12 25 3 0.21 26 1 0.07 26 1 0.09 13 21 5 0.28 24 1 0.06 24 2 0.11 14 18 10 0.50 22 1 0.06 23 2 0.15 15 20 15 0.81 21 1 0.06 21 4 0.21 16 30 35 3.6 24 11 1.2 20 8 0.45 17 25 11 0.79 20 10 0.57 20 13 0.73 18 77 59 29 19 8 0.42 20 15 0.84 19 101 119 41 18 7 0.32 21 10 0.66 20 143 161 86 17 5 0.23 18 4 0.19 21 132 70 34 16 4 0.16 17 4 0.17 22 72 9 1.8 15 2 0.09 17 3 0.15 23 80 85 29 15 2 0.09 16 3 0.14 24 82 105 28 14 3 0.10 16 3 0.13 25 146 279 235 14 3 0.11 15 3 0.12 26 200 419 373 13 3 0.12 19 9 0.61 27 214 422 318 14 4 0.13 17 4 0.19 28 147 248 106 13 4 0.14 15 4 0.15 29 166 219 205 13 5 0.16 14 3 0.12 30 121 21 7.5 38 45 9.8 14 3 0.10 31 --- --- --- 25 26 2.0 --- --- --- TOTAL 2157 --- 1546.28 937 --- 68.10 1139 --- 1044.65 102 RIO GRANDE DE ARECIBO BASIN 50025155 RIO SALIENTE AT COABEY NEAR JAYUYA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) JULY AUGUST SEPTEMBER 1 13 2 0.08 e21 e24 e2.2 38 45 6.5 2 13 2 0.07 e14 e14 e0.59 42 53 9.0 3 13 1 0.05 11 10 0.30 47 65 12 4 12 1 0.03 e12 e9 e0.29 38 52 6.1 5 12 1 0.03 18 19 1.6 24 24 1.7 6 20 17 1.8 13 13 0.47 18 10 0.51 7 16 11 0.59 11 9 0.28 15 8 0.31 8 12 1 0.03 11 9 0.25 13 7 0.26 9 23 22 3.1 9.5 8 0.20 13 7 0.23 10 16 9 0.44 26 38 6.3 13 6 0.22 11 12 2 0.08 47 95 34 12 6 0.18 12 12 3 0.08 30 36 3.9 11 6 0.16 13 11 3 0.09 15 5 0.20 10 5 0.15 14 12 3 0.11 14 1 0.04 9.9 5 0.14 15 13 3 0.12 11 1 0.03 13 9 0.46 16 11 4 0.11 12 1 0.03 34 39 5.0 17 10 4 0.11 10 8 0.21 13 11 0.38 18 10 4 0.12 10 18 0.48 29 36 6.0 19 9.5 5 0.12 10 14 0.37 19 19 1.1 20 9.2 5 0.13 9.7 9 0.24 e13 e13 e0.46 21 9.0 5 0.13 8.9 5 0.12 e11 e13 e0.39 22 10 6 0.16 21 23 3.1 11 12 0.34 23 10 6 0.17 21 14 1.0 9.9 11 0.30 24 8.9 6 0.14 18 9 0.78 12 11 0.35 25 8.4 6 0.14 17 10 0.60 16 10 0.42 26 8.2 6 0.13 12 2 0.05 12 9 0.29 27 8.4 6 0.14 10 1 0.04 e10 e8 e0.24 28 12 6 0.20 13 8 0.49 10 8 0.22 29 11 6 0.17 15 1 0.05 9.9 7 0.19 30 8.5 6 0.14 20 12 1.4 9.3 6 0.16 31 15 21 2.6 25 24 1.7 --- --- --- TOTAL 369.1 --- 11.41 496.1 --- 61.31 536.0 --- 53.76 YEAR 10585.0 6250.15 e Estimated WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 PARTICLE SIZE DISTRIBUTION OF SUSPENDED SEDIMENT Sus- Suspnd. Suspnd. Suspnd. Suspnd. Suspnd. Suspnd. Suspnd. Suspnd. Suspnd. pended Sus- sedi- sedi- sedi- sedi- sedi- sedi- sedi- sedi- sedi- Instan- sedi- pended ment, ment, ment, ment, ment, ment, ment, ment, ment, taneous ment sedi- falldia falldia falldia falldia falldia sieve sieve sieve sieve dis- concen- ment nat wat nat wat nat wat nat wat nat wat diametr diametr diametr diametr Date Time charge, tration load, percent percent percent percent percent percent percent percent percent cfs mg/L tons/d <.002mm <.004mm <.008mm <.016mm <.031mm <.062mm <.125mm <.25mm <.5 mm (00061) (80154) (80155) (70326) (70327) (70328) (70329) (70330) (70331) (70332) (70333) (70334) NOV 08... 0630 1220 4460 14700 22 27 38 45 61 74 97 99 99 Suspnd. sedi- ment, sieve diametr Date percent <1 mm (70335) NOV 08... 100 103 RIO GRANDE DE ARECIBO BASIN 50025850 RIO JAUCA AT PASO PALMA, PR LOCATION.--Lat 18°12'50", long 66°38'44", Hydrologic Unit 21010001, 5.13 mi (8.2 km) southeast from Utuado Plaza, 4.5 mi (7.24 km) south of Lago Caonillas Dam and 6.15 mi (9.89 km) northeast from Adjuntas Plaza. DRAINAGE AREA.--6.89 mi2 (17.8 km2). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--May 2000 to current year. GAGE.--Water-stage recorder. Elevation of gage is 1,197 ft (365 m), from topographic map. REMARKS.--Records fair except those for June 28 to July 23 and estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. Discharge, cubic feet per second WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 21 15 15 14 8.6 5.8 10 28 8.9 5.9 6.2 11 2 20 37 16 14 8.6 5.7 8.6 29 8.4 6.0 6.5 22 3 19 32 31 14 8.9 5.6 8.7 25 10 5.9 8.7 20 4 18 19 21 13 8.8 5.4 6.9 24 19 5.9 8.1 16 5 18 20 16 15 8.0 5.3 25 21 21 5.8 6.3 12 6 17 31 16 17 7.6 5.2 43 19 14 11 6.5 8.8 7 17 22 15 14 7.4 5.2 25 19 12 12 5.9 7.9 8 16 151 14 13 7.2 5.4 18 17 10 7.3 8.0 8.1 9 17 65 14 13 7.1 5.5 15 16 9.9 6.8 6.8 7.3 10 37 39 14 12 7.1 5.4 12 16 9.0 6.6 8.8 7.6 11 23 31 43 12 6.9 13 11 15 8.6 6.3 8.9 7.8 12 18 28 22 12 6.7 11 10 14 8.8 6.1 9.9 8.6 13 17 54 16 11 6.7 6.6 9.2 13 8.8 6.1 8.8 7.2 14 16 37 15 11 6.6 5.8 8.6 13 8.4 6.1 9.3 6.6 15 18 34 14 11 6.5 5.6 8.6 12 7.8 7.4 7.0 9.9 16 16 28 22 11 6.4 6.9 14 13 7.7 5.8 6.8 18 17 16 25 48 11 6.3 9.5 13 12 8.0 5.8 6.6 9.0 18 17 23 e25 10 7.2 6.6 14 11 8.3 5.8 9.3 15 19 15 22 23 10 15 6.4 29 11 7.9 5.7 7.8 11 20 14 21 18 10 9.5 5.7 61 11 7.6 5.1 6.2 8.1 21 14 20 75 9.8 6.8 5.4 59 10 7.2 5.3 5.8 7.4 22 14 19 37 9.8 6.2 5.3 29 9.8 6.9 5.9 7.1 e6.9 23 18 18 30 9.6 6.0 5.1 43 9.7 6.7 7.4 6.6 e6.5 24 15 21 24 9.8 5.9 5.1 62 9.4 6.7 5.8 8.8 e6.7 25 14 17 21 9.4 5.8 4.9 83 9.0 6.5 5.4 11 8.7 26 13 17 19 9.2 6.4 4.8 76 8.8 7.2 5.3 6.7 7.4 27 21 17 17 9.0 6.5 4.8 80 8.8 7.2 e5.2 5.9 6.9 28 27 16 17 9.1 5.9 5.1 62 8.8 6.8 9.5 24 6.5 29 34 17 16 9.3 --- 21 70 8.7 6.2 8.5 12 6.5 30 22 16 15 9.3 --- 15 48 9.0 6.0 5.7 14 6.2 31 16 --- 15 9.0 --- 12 --- 9.0 --- e5.4 16 --- TOTAL 578 912 704 351.3 206.6 220.1 962.6 440.0 271.5 202.8 270.3 291.6 MEAN 18.6 30.4 22.7 11.3 7.38 7.10 32.1 14.2 9.05 6.54 8.72 9.72 MAX 37 151 75 17 15 21 83 29 21 12 24 22 MIN 13 15 14 9.0 5.8 4.8 6.9 8.7 6.0 5.1 5.8 6.2 AC-FT 1150 1810 1400 697 410 437 1910 873 539 402 536 578 STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 2000 - 2002, BY WATER YEAR (WY) MEAN 32.3 27.3 16.7 8.83 6.21 6.23 19.3 18.0 8.76 8.58 14.1 29.4 MAX 45.9 30.4 22.7 11.3 7.38 7.10 32.1 21.9 9.12 13.7 18.9 43.4 (WY) 2001 2002 2002 2002 2002 2002 2002 2001 2001 2001 2000 2000 MIN 18.6 24.2 10.7 6.34 5.04 5.36 6.60 14.2 8.11 5.54 8.72 9.72 (WY) 2002 2001 2001 2001 2001 2001 2001 2002 2000 2000 2002 2002 SUMMARY STATISTICS FOR 2001 CALENDAR YEAR FOR 2002 WATER YEAR WATER YEARS 2000 - 2002 ANNUAL TOTAL 5773.8 5410.8 ANNUAL MEAN 15.8 14.8 15.7 HIGHEST ANNUAL MEAN 16.6 2001 LOWEST ANNUAL MEAN 14.8 2002 HIGHEST DAILY MEAN 193 May 6 151 Nov 8 235 Aug 23 2000 LOWEST DAILY MEAN 3.5 Mar 17 4.8 Mar 26 3.5 Mar 17 2001 ANNUAL SEVEN-DAY MINIMUM 3.6 Mar 14 5.0 Mar 22 3.6 Mar 14 2001 MAXIMUM PEAK FLOW 466 Dec 11 1590 May 6 2001 MAXIMUM PEAK STAGE 3.88 Dec 11 6.59 May 6 2001 INSTANTANEOUS LOW FLOW 3.2 Mar 17 2001 ANNUAL RUNOFF (AC-FT) 11450 10730 11380 10 PERCENT EXCEEDS 30 26 32 50 PERCENT EXCEEDS 9.7 10 9.6 90 PERCENT EXCEEDS 4.7 5.9 5.2 e Estimated 104 RIO GRANDE DE ARECIBO BASIN 50025850 RIO JAUCA AT PASO PALMA, PR--Continued O N D 2001 J F M A M J J A S 2002 1 2 5 10 10 20 50 100 100 200 500 1000 DISCHARGE, IN CUBIC FEET PER SECOND 105 RIO GRANDE DE ARECIBO BASIN 50025850 RIO JAUCA AT PASO PALMA, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--May 2000 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: October 2000 to current year. INSTRUMENTATION.--USDH-48 and automatic sediment samplers since 2000. REMARKS.--Sediment samples were collected by a local observer on a weekly basis. During high flow events sediment samples were collected with automatic sediment sampler. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATION: Maximum daily mean, 911 mg/L September 21, 2001; Minimum daily mean, 1 mg/L during water years 2001 and 2002. SEDIMENT LOADS: Maximum daily mean, 1,050 tons (952 tonnes) September 21, 2001; Minimum daily mean, 0.01 ton (0.01 tonne) several days during water year 2001. EXTREMES FOR CURRENT YEAR 2002.-- SEDIMENT CONCENTRATION: Maximum daily mean, 842 mg/L September 8, 2001; Minimum daily mean, 1 mg/L several days. SEDIMENT LOADS: Maximum daily mean, 514 tons (466 tonnes) September 8, 2001; Minimum daily mean, 0.02 ton (0.02 tonne) July 24, 2002. SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) OCTOBER NOVEMBER DECEMBER 1 21 4 0.20 15 8 0.31 15 12 0.50 2 20 4 0.20 37 616 184 16 12 0.49 3 19 5 0.25 32 96 11 31 96 15 4 18 6 0.30 19 33 1.7 21 32 2.1 5 18 7 0.35 20 37 2.1 16 5 0.21 6 17 8 0.40 31 77 7.1 16 3 0.14 7 17 10 0.44 22 24 1.4 15 3 0.13 8 16 11 0.48 151 842 514 14 3 0.13 9 17 11 0.52 65 110 21 14 4 0.14 10 37 132 22 39 25 2.7 14 4 0.18 11 23 34 2.5 31 17 1.4 43 293 148 12 18 7 0.31 28 16 1.2 22 87 5.3 13 17 6 0.27 54 342 129 16 84 3.7 14 16 6 0.23 37 101 10 15 81 3.3 15 18 34 1.9 34 77 8.6 14 78 3.0 16 16 14 0.63 28 48 3.8 22 93 6.4 17 16 13 0.58 25 22 1.5 48 263 96 18 17 16 0.75 23 16 1.0 e25 e70 e5.4 19 15 6 0.22 22 11 0.64 23 51 3.3 20 14 7 0.28 21 7 0.39 18 16 0.81 21 14 9 0.34 20 6 0.34 75 347 194 22 14 11 0.42 19 6 0.31 37 110 12 23 18 30 2.1 18 7 0.34 30 45 3.7 24 15 14 0.62 21 28 1.7 24 9 0.60 25 14 9 0.34 17 10 0.45 21 5 0.31 26 13 9 0.31 17 7 0.30 19 6 0.29 27 21 44 4.0 17 5 0.21 17 5 0.26 28 27 82 12 16 7 0.31 17 5 0.22 29 34 113 20 17 10 0.44 16 4 0.18 30 22 33 2.2 16 12 0.52 15 4 0.15 31 16 9 0.39 --- --- --- 15 4 0.14 TOTAL 578 --- 75.53 912 --- 907.76 704 --- 506.08 106 RIO GRANDE DE ARECIBO BASIN 50025850 RIO JAUCA AT PASO PALMA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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 FEBRUARY MARCH 1 14 4 0.17 8.6 4 0.09 5.8 6 0.09 2 14 4 0.14 8.6 4 0.09 5.7 6 0.09 3 14 3 0.12 8.9 4 0.10 5.6 7 0.10 4 13 4 0.14 8.8 4 0.09 5.4 7 0.11 5 15 5 0.21 8.0 3 0.07 5.3 8 0.11 6 17 6 0.29 7.6 3 0.06 5.2 7 0.10 7 14 8 0.30 7.4 2 0.04 5.2 6 0.08 8 13 9 0.31 7.2 2 0.04 5.4 4 0.06 9 13 7 0.24 7.1 2 0.05 5.5 3 0.05 10 12 5 0.16 7.1 3 0.05 5.4 2 0.03 11 12 3 0.08 6.9 3 0.05 13 48 3.6 12 12 2 0.07 6.7 3 0.05 11 21 0.81 13 11 3 0.08 6.7 2 0.04 6.6 4 0.07 14 11 3 0.09 6.6 2 0.04 5.8 4 0.06 15 11 4 0.10 6.5 2 0.03 5.6 4 0.07 16 11 3 0.09 6.4 2 0.03 6.9 7 0.15 17 11 3 0.07 6.3 2 0.03 9.5 11 0.30 18 10 3 0.09 7.2 2 0.04 6.6 6 0.10 19 10 4 0.11 15 37 2.0 6.4 4 0.07 20 10 6 0.15 9.5 11 0.29 5.7 2 0.04 21 9.8 8 0.20 6.8 7 0.13 5.4 3 0.04 22 9.8 10 0.25 6.2 6 0.10 5.3 3 0.05 23 9.6 10 0.26 6.0 5 0.09 5.1 6 0.08 24 9.8 10 0.27 5.9 5 0.08 5.1 8 0.12 25 9.4 10 0.25 5.8 4 0.07 4.9 8 0.10 26 9.2 8 0.19 6.4 4 0.07 4.8 7 0.09 27 9.0 5 0.12 6.5 5 0.08 4.8 6 0.08 28 9.1 3 0.06 5.9 5 0.08 5.1 6 0.08 29 9.3 3 0.07 --- --- --- 21 76 13 30 9.3 3 0.08 --- --- --- 15 30 1.7 31 9.0 4 0.09 --- --- --- 12 19 0.66 TOTAL 351.3 --- 4.85 206.6 --- 3.98 220.1 --- 22.09 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) APRIL MAY JUNE 1 10 14 0.39 28 79 6.0 8.9 5 0.12 2 8.6 10 0.22 29 85 7.2 8.4 5 0.11 3 8.7 5 0.12 25 53 3.6 10 11 0.38 4 6.9 4 0.07 24 41 2.6 19 48 3.4 5 25 106 20 21 38 2.2 21 44 3.1 6 43 171 28 19 35 1.8 14 17 0.70 7 25 57 4.4 19 33 1.7 12 5 0.16 8 18 25 1.2 17 30 1.4 10 2 0.05 9 15 14 0.57 16 27 1.2 9.9 1 0.03 10 12 9 0.32 16 24 1.0 9.0 2 0.05 11 11 6 0.20 15 21 0.86 8.6 3 0.08 12 10 4 0.12 14 19 0.69 8.8 5 0.11 13 9.2 4 0.09 13 16 0.57 8.8 5 0.11 14 8.6 3 0.08 13 13 0.45 8.4 4 0.10 15 8.6 3 0.08 12 10 0.34 7.8 4 0.09 16 14 255 13 13 13 0.51 7.7 4 0.08 17 13 43 1.9 12 18 0.61 8.0 4 0.08 18 14 19 0.89 11 16 0.49 8.3 3 0.07 19 29 143 21 11 15 0.45 7.9 3 0.07 20 61 294 67 11 14 0.41 7.6 4 0.08 21 59 276 59 10 14 0.38 7.2 5 0.10 22 29 69 5.6 9.8 13 0.34 6.9 7 0.12 23 43 206 38 9.7 12 0.32 6.7 6 0.10 24 62 525 158 9.4 11 0.29 6.7 4 0.07 25 83 513 216 9.0 11 0.26 6.5 2 0.04 26 76 407 146 8.8 10 0.23 7.2 3 0.05 27 80 260 74 8.8 9 0.21 7.2 4 0.07 28 62 279 54 8.8 8 0.20 6.8 5 0.09 29 70 348 128 8.7 7 0.18 6.2 5 0.08 30 48 209 33 9.0 7 0.16 6.0 4 0.07 31 --- --- --- 9.0 6 0.14 --- --- --- TOTAL 962.6 --- 1071.25 440.0 --- 36.79 271.5 --- 9.76 107 RIO GRANDE DE ARECIBO BASIN 50025850 RIO JAUCA AT PASO PALMA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) JULY AUGUST SEPTEMBER 1 5.9 2 0.03 6.2 3 0.06 11 59 1.7 2 6.0 2 0.03 6.5 2 0.04 22 144 24 3 5.9 2 0.04 8.7 9 0.30 20 94 5.4 4 5.9 3 0.05 8.1 9 0.21 16 32 1.5 5 5.8 4 0.06 6.3 4 0.07 12 14 0.46 6 11 26 1.9 6.5 3 0.05 8.8 11 0.26 7 12 23 0.97 5.9 3 0.05 7.9 10 0.22 8 7.3 3 0.06 8.0 5 0.11 8.1 10 0.22 9 6.8 3 0.05 6.8 8 0.14 7.3 10 0.19 10 6.6 3 0.05 8.8 12 0.28 7.6 9 0.19 11 6.3 3 0.05 8.9 15 0.36 7.8 9 0.19 12 6.1 3 0.05 9.9 12 0.32 8.6 9 0.21 13 6.1 4 0.07 8.8 13 0.36 7.2 9 0.18 14 6.1 6 0.11 9.3 6 0.15 6.6 10 0.17 15 7.4 8 0.17 7.0 5 0.09 9.9 15 0.53 16 5.8 10 0.16 6.8 4 0.07 18 33 1.9 17 5.8 9 0.15 6.6 3 0.06 9.0 10 0.25 18 5.8 7 0.12 9.3 10 0.37 15 28 2.4 19 5.7 5 0.08 7.8 14 0.29 11 18 0.51 20 5.1 4 0.06 6.2 12 0.21 8.1 17 0.38 21 5.3 3 0.05 5.8 12 0.19 7.4 17 0.34 22 5.9 2 0.04 7.1 12 0.23 e6.9 e16 e0.31 23 7.4 1 0.03 6.6 12 0.21 e6.5 e16 e0.28 24 5.8 1 0.02 8.8 20 1.0 e6.7 e15 e0.27 25 5.4 2 0.03 11 17 0.62 8.7 6 0.14 26 5.3 3 0.04 6.7 7 0.12 7.4 4 0.07 27 e5.2 e3 e0.04 5.9 6 0.10 6.9 3 0.06 28 9.5 14 0.51 24 169 43 6.5 3 0.06 29 8.5 9 0.23 12 132 4.2 6.5 5 0.08 30 5.7 5 0.08 14 113 5.2 6.2 5 0.08 31 e5.4 e3 e0.05 16 80 4.0 --- --- --- TOTAL 202.8 --- 5.38 270.3 --- 62.46 291.6 --- 42.55 YEAR 5410.8 2748.48 e Estimated WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT Sus- Suspnd. pended Sus- sedi- Instan- sedi- pended ment, taneous ment sedi- sieve dis- concen- ment diametr Date Time charge, tration load, percent cfs mg/L tons/d <.062mm (00061) (80154) (80155) (70331) DEC 21... 1900 184 1160 578 98 APR 25... 1603 383 1780 1850 94 27... 1959 183 467 231 96 108 RIO GRANDE DE ARECIBO BASIN 50026025 RIO CAONILLAS AT PASO PALMA, PR LOCATION.--Lat 18°13'53", long 66°38'14", Hydrologic Unit 21010001, 3.5 mi (5.6 km) south of Lago Caonillas Dam, 4.8 mi (7.72 km) southeast of Utuado Plaza and 2.78 mi (4.47 km) east of Lago Viví Dam. DRAINAGE AREA.--37.9 mi2 (98.2 km2). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--October 1995 to current year. GAGE.--Water-stage recorder. Elevation of gage is 984 ft (300 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 2001 TO SEPTEMBER 2002 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 67 57 69 58 33 24 101 225 55 33 71 70 2 63 199 94 57 32 24 95 252 47 32 60 161 3 63 170 183 56 31 23 85 192 123 31 86 123 4 59 82 124 54 33 22 65 154 98 31 53 167 5 58 83 89 72 e32 21 119 131 308 30 45 e101 6 56 139 78 88 e31 21 217 118 161 37 42 e66 7 52 102 72 68 e29 21 150 111 114 52 31 e57 8 51 1280 68 59 e28 21 158 103 82 33 34 e52 9 55 436 64 56 e28 22 168 93 71 58 31 e46 10 104 233 62 53 e28 46 126 89 63 50 53 e53 11 103 173 99 51 e26 178 111 84 59 33 63 e45 12 74 146 85 50 e25 97 96 79 57 31 79 e39 13 66 167 68 48 e25 42 85 75 54 30 47 e37 14 59 142 64 47 25 33 78 72 51 30 47 e35 15 62 127 60 46 24 30 76 70 48 35 35 e39 16 58 114 69 45 24 59 104 73 46 29 37 e80 17 58 103 104 44 23 81 96 71 49 29 32 e46 18 63 97 81 43 31 40 124 64 49 27 33 e68 19 56 92 95 42 68 41 218 61 48 26 31 e65 20 50 88 68 41 49 32 334 59 45 25 28 e44 21 47 85 210 40 31 29 357 56 42 25 26 e36 22 47 81 149 41 27 27 197 54 40 28 100 e34 23 55 79 118 40 25 26 406 52 38 31 66 e35 24 48 91 112 42 25 24 352 51 38 26 43 e39 25 44 78 93 39 24 23 523 49 37 24 52 e49 26 44 75 83 37 26 23 492 47 43 23 34 e40 27 70 75 76 35 27 23 727 48 44 23 30 e35 28 96 76 70 35 24 29 434 48 39 39 56 e33 29 111 78 66 36 --- 229 599 46 35 38 54 e31 30 78 74 63 35 --- 162 362 59 34 26 53 e29 31 58 --- 61 34 --- 120 --- 64 --- 36 73 --- TOTAL 1975 4822 2797 1492 834 1593 7055 2750 2018 1001 1525 1755 MEAN 63.7 161 90.2 48.1 29.8 51.4 235 88.7 67.3 32.3 49.2 58.5 MAX 111 1280 210 88 68 229 727 252 308 58 100 167 MIN 44 57 60 34 23 21 65 46 34 23 26 29 AC-FT 3920 9560 5550 2960 1650 3160 13990 5450 4000 1990 3020 3480 CFSM 1.68 4.24 2.38 1.27 0.79 1.35 6.20 2.34 1.77 0.85 1.30 1.54 IN. 1.94 4.73 2.74 1.46 0.82 1.56 6.92 2.70 1.98 0.98 1.50 1.72 STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1996 - 2002, BY WATER YEAR (WY) MEAN 156 141 77.0 56.8 48.3 38.6 77.1 87.5 69.6 52.6 85.4 273 MAX 248 292 143 89.8 86.0 51.4 235 130 161 117 156 815 (WY) 1999 2000 2000 1997 1996 2002 2002 1998 1999 1996 1998 1998 MIN 63.7 44.2 21.0 19.6 24.0 25.7 17.0 29.1 16.1 15.5 47.9 33.2 (WY) 2002 1998 1998 1998 2001 1997 1997 1997 1997 1997 1996 1997 SUMMARY STATISTICS FOR 2001 CALENDAR YEAR FOR 2002 WATER YEAR WATER YEARS 1996 - 2002 ANNUAL TOTAL 25782 29617 ANNUAL MEAN 70.6 81.1 96.8 HIGHEST ANNUAL MEAN 137 1998 LOWEST ANNUAL MEAN 49.9 1997 HIGHEST DAILY MEAN 1280 Nov 8 1280 Nov 8 13000 Sep 22 1998 LOWEST DAILY MEAN 15 Apr 19 21 Mar 5 10 Jul 4 1997 ANNUAL SEVEN-DAY MINIMUM 16 Mar 12 22 Mar 3 11 Jul 1 1997 MAXIMUM PEAK FLOW 5020 Nov 8 36000 Sep 22 1998 MAXIMUM PEAK STAGE 14.47 Nov 8 31.15 Sep 22 1998 INSTANTANEOUS LOW FLOW 19 Mar 7 9.5 Jul 6 1997 ANNUAL RUNOFF (AC-FT) 51140 58750 70140 ANNUAL RUNOFF (CFSM) 1.86 2.14 2.55 ANNUAL RUNOFF (INCHES) 25.28 29.04 34.67 10 PERCENT EXCEEDS 134 149 191 50 PERCENT EXCEEDS 50 55 52 90 PERCENT EXCEEDS 20 27 22 e Estimated 109 RIO GRANDE DE ARECIBO BASIN 50026025 RIO CAONILLAS AT PASO PALMA, PR--Continued O N D 2001 J F M A M J J A S 2002 10 20 50 100 100 200 500 1000 1000 2000 5000 10,000 DISCHARGE, IN CUBIC FEET PER SECOND 110 RIO GRANDE DE ARECIBO BASIN 50026025 RIO CAONILLAS AT PASO PALMA, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORDS.--October 1995 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: October 1995 to current year. INSTRUMENTATION.--USDH-48 sediment sampler and automatic sediment sampler since 1996. REMARKS.--Sediment samples were collected by a local observer on a weekly basis. During high flow events sediments samples were collected with automatic sediment sampler. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATION: Maximum daily mean, 24,800 mg/L September 22, 1998; Minimum daily mean, 1 mg/L several years. SEDIMENT LOADS: Maximum daily mean, e952,000 tons (e864,000 tonnes) September 22, 1998; Minimum daily mean, 0.04 ton (0.03 tonne) December 29-30, 1998. EXTREMES FOR CURRENT YEAR 2001.-- SEDIMENT CONCENTRATION: Maximum daily mean, 2,140 mg/L May 6, 2001; Minimum daily mean, 1 mg/L several days. SEDIMENT LOADS: Maximum daily mean, 15,100 tons (13,700 tonnes) May 6, 2001; Minimum daily mean, 0.05 ton (0.04 tonne) March 14, 2001. EXTREMES FOR CURRENT YEAR 2002.-- SEDIMENT CONCENTRATION: Maximum daily mean, 2,470 mg/L April 29, 2002; Minimum daily mean, 1 mg/L June 23, 2002. SEDIMENT LOADS: Maximum daily mean, 11,700 tons (10,614 tonnes) November 8, 2001; Minimum daily mean, 0.13 ton (0.12 tonne) June 23, 2002. SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2000 TO SEPTEMBER 2001 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) OCTOBER NOVEMBER DECEMBER 1 242 336 311 253 1400 2740 62 45 7.7 2 211 248 158 266 409 335 53 27 3.9 3 260 473 534 249 243 185 50 11 1.6 4 201 142 84 178 32 16 49 9 1.2 5 161 94 41 148 25 9.8 48 8 1.0 6 175 193 116 129 22 7.8 48 7 0.92 7 238 408 313 117 21 6.6 47 7 0.86 8 259 321 262 108 19 5.6 47 6 0.82 9 191 384 200 101 17 4.6 46 6 0.77 10 164 265 117 93 15 3.7 45 6 0.71 11 274 1310 2710 87 13 2.9 e45 e4 e0.54 12 176 178 84 245 1250 2260 45 4 0.45 13 151 142 58 153 255 128 45 7 0.81 14 133 92 33 108 39 12 44 9 1.1 15 125 55 18 98 32 8.6 49 11 1.4 16 286 1700 3880 90 30 7.3 47 12 1.6 17 208 222 147 81 22 4.8 47 13 1.7 18 161 95 44 76 14 2.9 45 10 1.3 19 145 54 21 72 8 1.5 44 7 0.80 20 259 1450 2750 69 7 1.2 43 4 0.48 21 226 272 203 67 6 1.1 42 4 0.42 22 336 688 1180 67 6 1.2 40 3 0.38 23 365 685 994 64 8 1.4 40 3 0.35 24 282 452 365 65 10 1.8 39 3 0.32 25 268 376 331 59 12 2.0 39 3 0.32 26 209 264 152 56 13 2.0 42 8 0.96 27 192 191 106 55 10 1.6 45 18 2.3 28 186 200 103 54 7 1.1 39 15 1.6 29 172 162 94 53 5 0.72 38 12 1.3 30 176 219 113 61 21 4.1 38 10 1.0 31 142 48 18 --- --- --- 38 7 0.71 TOTAL 6574 --- 15540 3322 --- 5760.32 1389 --- 39.32 111 RIO GRANDE DE ARECIBO BASIN 50026025 RIO CAONILLAS AT PASO PALMA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2000 TO SEPTEMBER 2001 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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 FEBRUARY MARCH 1 37 6 0.64 30 7 0.59 23 1 0.06 2 36 7 0.66 30 10 0.79 28 1 0.08 3 36 8 0.74 27 12 0.87 23 1 0.06 4 35 10 1.0 29 13 1.0 21 1 0.06 5 35 13 1.3 25 12 0.78 21 2 0.10 6 35 16 1.5 25 9 0.62 e20 e2 e0.13 7 34 18 1.6 25 7 0.48 e18 e3 e0.14 8 34 13 1.2 23 6 0.36 21 3 0.15 9 33 8 0.74 23 4 0.27 17 2 0.12 10 33 4 0.37 22 3 0.19 17 2 0.10 11 33 3 0.30 22 2 0.14 17 2 0.09 12 33 3 0.26 21 3 0.18 16 2 0.07 13 33 2 0.22 21 3 0.19 16 1 0.06 14 33 2 0.18 21 3 0.19 17 1 0.05 15 32 2 0.18 21 4 0.22 16 2 0.09 16 33 2 0.18 21 4 0.24 16 3 0.13 17 36 12 1.1 20 5 0.25 16 4 0.17 18 32 11 0.95 20 6 0.34 16 5 0.22 19 31 8 0.70 20 11 0.61 17 7 0.33 20 31 6 0.48 20 17 0.88 17 10 0.45 21 30 3 0.28 19 20 1.0 17 13 0.60 22 29 3 0.26 24 15 0.97 23 17 1.0 23 32 4 0.32 29 11 0.78 53 36 8.7 24 31 4 0.33 32 6 0.52 188 1070 1830 25 29 4 0.28 31 2 0.18 65 166 41 26 28 3 0.24 26 2 0.12 31 33 2.8 27 32 9 0.82 23 1 0.08 27 14 1.0 28 38 7 0.76 22 1 0.06 24 13 0.85 29 46 29 4.5 --- --- --- 22 15 0.91 30 57 42 6.9 --- --- --- 20 14 0.76 31 33 11 0.99 --- --- --- 19 12 0.62 TOTAL 1060 --- 29.98 672 --- 12.90 862 --- 1890.90 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) APRIL MAY JUNE 1 18 11 0.54 23 18 1.2 30 11 0.92 2 18 10 0.47 20 13 0.68 29 9 0.71 3 20 8 0.44 18 12 0.58 128 333 246 4 21 7 0.40 17 12 0.56 90 66 21 5 38 14 2.0 16 12 0.52 63 44 8.8 6 43 19 2.3 527 2140 15100 40 14 1.5 7 31 13 1.1 449 975 2460 33 12 1.1 8 25 11 0.73 162 265 163 30 11 0.93 9 24 10 0.64 134 233 98 28 11 0.82 10 21 9 0.50 199 503 536 27 10 0.73 11 22 8 0.50 160 277 145 26 10 0.69 12 20 10 0.54 91 85 22 25 9 0.64 13 19 12 0.59 67 21 3.9 24 9 0.59 14 18 14 0.67 57 13 2.0 26 9 0.65 15 18 14 0.68 50 9 1.2 26 10 0.66 16 17 12 0.55 46 11 1.4 26 10 0.68 17 16 9 0.40 42 11 1.2 31 15 1.7 18 16 7 0.30 45 18 2.6 52 31 5.5 19 15 7 0.28 58 33 5.5 33 27 2.4 20 15 6 0.26 39 12 1.3 25 19 1.3 21 19 15 0.86 36 9 0.86 23 17 1.0 22 25 21 1.5 35 8 0.75 47 50 11 23 31 24 2.1 34 7 0.64 61 64 12 24 28 28 2.1 32 7 0.60 55 45 7.8 25 24 24 1.5 31 7 0.59 42 27 3.3 26 69 196 161 30 7 0.57 44 34 4.1 27 e119 e377 e201 51 58 15 29 23 1.8 28 e29 e75 e6.5 50 27 4.2 81 104 40 29 29 38 2.8 36 17 1.6 60 34 6.0 30 28 26 2.0 32 15 1.3 127 211 152 31 --- --- --- 32 14 1.2 --- --- --- TOTAL 836 --- 395.25 2619 --- 18573.95 1361 --- 536.32 112 RIO GRANDE DE ARECIBO BASIN 50026025 RIO CAONILLAS AT PASO PALMA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2000 TO SEPTEMBER 2001 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) JULY AUGUST SEPTEMBER 1 74 57 13 62 44 11 148 202 145 2 45 26 3.3 54 21 3.5 110 100 30 3 37 14 1.5 137 293 245 160 319 242 4 34 5 0.50 89 27 8.6 119 36 14 5 33 5 0.41 56 10 1.5 86 1 0.35 6 29 4 0.34 52 6 0.86 113 81 41 7 27 4 0.30 50 5 0.67 115 102 39 8 25 4 0.26 45 3 0.43 184 575 619 9 24 3 0.23 42 3 0.34 191 264 166 10 54 133 42 40 3 0.33 135 170 66 11 55 99 14 53 28 8.2 100 53 14 12 89 159 110 45 10 1.4 119 161 90 13 104 203 98 37 3 0.30 91 52 13 14 344 1250 3230 73 90 41 78 29 6.1 15 207 321 266 65 100 22 76 21 4.2 16 85 23 5.4 41 14 1.5 74 14 2.8 17 62 16 2.7 42 12 1.4 132 291 233 18 62 9 1.5 45 11 1.3 138 358 149 19 57 7 1.1 72 42 13 95 48 13 20 46 5 0.66 55 23 3.7 260 1610 2720 21 43 3 0.40 44 12 1.4 301 1530 2320 22 89 50 25 56 17 3.3 199 254 150 23 76 54 12 426 917 1430 319 501 905 24 69 53 10 142 104 43 209 257 170 25 51 10 1.4 101 16 4.6 132 54 20 26 69 56 19 136 97 49 115 7 2.2 27 72 38 9.2 89 29 7.0 104 25 8.7 28 48 7 0.94 77 16 3.3 94 51 14 29 48 14 2.0 72 11 2.1 80 8 1.8 30 60 26 4.4 73 11 2.1 72 6 1.1 31 44 6 0.70 96 54 24 --- --- --- TOTAL 2162 --- 3876.24 2467 --- 1935.83 4149 --- 8200.25 YEAR 27473 56791.26 e Estimated 113 RIO GRANDE DE ARECIBO BASIN 50026025 RIO CAONILLAS AT PASO PALMA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) OCTOBER NOVEMBER DECEMBER 1 67 5 0.87 57 13 2.1 69 5 1.0 2 63 4 0.74 199 529 1130 94 49 17 3 63 4 0.70 170 239 158 183 272 232 4 59 5 0.76 82 34 7.7 124 110 42 5 58 6 0.87 83 17 3.7 89 18 4.4 6 56 6 0.95 139 8 2.9 78 10 2.1 7 52 7 0.94 102 7 2.0 72 9 1.7 8 51 6 0.81 1280 1690 11700 68 8 1.5 9 55 5 0.74 436 149 252 64 7 1.2 10 104 75 33 233 29 19 62 7 1.2 11 103 60 17 173 29 13 99 80 41 12 74 37 7.4 146 26 10 85 71 19 13 66 29 5.1 167 23 10 68 5 0.92 14 59 25 4.0 142 20 7.5 64 5 0.87 15 62 22 3.7 127 13 4.3 60 5 0.80 16 58 17 2.7 114 6 1.8 69 21 5.3 17 58 9 1.3 103 4 1.2 104 67 27 18 63 11 1.9 97 6 1.5 81 56 12 19 56 14 2.0 92 6 1.5 95 58 16 20 50 13 1.7 88 6 1.5 68 27 5.1 21 47 11 1.4 85 5 1.2 210 560 933 22 47 9 1.1 81 5 1.1 149 297 136 23 55 14 2.4 79 5 1.1 118 76 24 24 48 16 2.1 91 5 1.2 112 62 19 25 44 12 1.4 78 5 1.1 93 48 12 26 44 8 0.98 75 5 1.0 83 35 7.7 27 70 39 13 75 5 1.0 76 24 4.8 28 96 97 33 76 6 1.3 70 22 4.2 29 111 120 47 78 6 1.3 66 21 3.8 30 78 37 9.4 74 6 1.2 63 20 3.5 31 58 9 1.4 --- --- --- 61 19 3.2 TOTAL 1975 --- 200.36 4822 --- 13341.2 2797 --- 1583.29 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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 FEBRUARY MARCH 1 58 19 2.9 33 5 0.43 24 3 0.19 2 57 18 2.7 32 4 0.38 24 3 0.19 3 56 17 2.6 31 4 0.33 23 3 0.19 4 54 16 2.4 33 4 0.32 22 3 0.21 5 72 15 3.0 e32 e4 e0.38 21 4 0.21 6 88 14 3.4 e31 e4 e0.33 21 4 0.22 7 68 14 2.5 e29 e4 e0.33 21 4 0.21 8 59 13 2.0 e28 e40 e0.33 21 3 0.20 9 56 12 1.8 e28 e4 e0.33 22 3 0.20 10 53 11 1.6 e28 e4 e0.33 46 28 7.7 11 51 10 1.4 e26 e4 e0.32 178 442 655 12 50 9 1.3 e25 e5 e0.14 97 145 54 13 48 9 1.1 e25 e5 e0.23 42 36 4.1 14 47 8 0.98 25 5 0.34 33 28 2.5 15 46 7 0.85 24 5 0.32 30 19 1.6 16 45 6 0.68 24 5 0.32 59 41 16 17 44 6 0.65 23 5 0.31 81 70 20 18 43 6 0.70 31 5 0.42 40 16 1.8 19 42 7 0.74 68 40 8.7 41 15 1.6 20 41 7 0.76 49 24 3.2 32 14 1.2 21 40 7 0.72 31 13 1.1 29 13 1.0 22 41 6 0.70 27 11 0.79 27 13 0.93 23 40 6 0.67 25 9 0.59 26 12 0.82 24 42 6 0.67 25 8 0.50 24 11 0.73 25 39 6 0.59 24 9 0.60 23 10 0.65 26 37 5 0.52 26 11 0.80 23 9 0.59 27 35 5 0.48 27 7 0.53 23 9 0.53 28 35 5 0.52 24 3 0.19 29 8 0.62 29 36 6 0.56 --- --- --- 229 1100 3390 30 35 6 0.55 --- --- --- 162 385 217 31 34 5 0.49 --- --- --- 120 97 33 TOTAL 1492 --- 40.53 834 --- 22.89 1593 --- 4413.19 114 RIO GRANDE DE ARECIBO BASIN 50026025 RIO CAONILLAS AT PASO PALMA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) APRIL MAY JUNE 1 101 72 21 225 49 30 55 8 1.2 2 95 63 17 252 303 297 47 9 1.1 3 85 53 13 192 201 106 123 189 172 4 65 33 5.8 154 105 44 98 50 13 5 119 128 85 131 42 15 308 710 1030 6 217 351 258 118 33 10 161 170 87 7 150 140 59 111 28 8.5 114 93 30 8 158 149 65 103 25 6.9 82 36 8.0 9 168 176 81 93 22 5.5 71 9 1.8 10 126 107 37 89 20 4.7 63 7 1.3 11 111 85 26 84 17 3.9 59 8 1.2 12 96 63 16 79 15 3.2 57 8 1.2 13 85 51 12 75 14 2.9 54 6 0.90 14 78 49 10 72 14 2.7 51 5 0.65 15 76 46 9.5 70 13 2.5 48 3 0.42 16 104 78 25 73 13 2.6 46 2 0.30 17 96 70 19 71 13 2.5 49 4 0.53 18 124 120 69 64 13 2.3 49 6 0.73 19 218 344 256 61 13 2.1 48 7 0.85 20 334 638 751 59 12 1.9 45 5 0.65 21 357 656 768 56 12 1.8 42 4 0.43 22 197 90 52 54 11 1.6 40 2 0.25 23 406 1450 4830 52 10 1.5 38 1 0.13 24 352 989 1510 51 10 1.4 38 2 0.18 25 523 2180 7260 49 9 1.2 37 2 0.24 26 492 1400 3110 47 9 1.2 43 2 0.21 27 727 2270 7370 48 10 1.3 44 2 0.26 28 434 521 860 48 11 1.5 39 3 0.33 29 599 2470 10300 46 8 0.99 35 4 0.40 30 362 258 333 59 7 1.1 34 5 0.44 31 --- --- --- 64 8 1.3 --- --- --- TOTAL 7055 --- 38228.3 2750 --- 569.09 2018 --- 1355.70 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) JULY AUGUST SEPTEMBER 1 33 5 0.41 71 149 32 70 40 9.0 2 32 4 0.37 60 44 7.3 161 322 311 3 31 4 0.33 86 111 64 123 112 42 4 31 4 0.31 53 83 12 167 385 445 5 30 3 0.27 45 65 8.0 e101 e75 e22.0 6 37 9 1.4 42 50 5.8 e66 e40 e7.2 7 52 22 3.6 31 37 3.1 e57 e24 e3.6 8 33 12 1.1 34 34 3.1 e52 e12 e1.7 9 58 56 18 31 33 2.7 e46 e16 e2.0 10 50 36 5.3 53 44 7.8 e53 e22 e3.1 11 33 10 0.93 63 55 12 e45 e24 e3.0 12 31 8 0.67 79 113 33 e39 e19 e2.0 13 30 6 0.51 47 43 5.6 e37 e13 e1.3 14 30 5 0.40 47 40 5.0 e35 e8 e0.73 15 35 4 0.40 35 29 2.8 e39 e4 e0.37 16 29 4 0.28 37 21 2.0 e80 e50 e11.0 17 29 3 0.23 32 12 1.1 e46 e18 e2.3 18 27 3 0.20 33 5 0.42 e68 e34 e10.0 19 26 2 0.18 31 5 0.40 e65 e37 e7.0 20 25 2 0.15 28 5 0.40 e44 e13 e1.5 21 25 2 0.14 26 6 0.41 e36 e7 e0.66 22 28 2 0.18 100 242 242 e34 e4 e0.41 23 31 3 0.23 66 55 10 e35 e6 e0.53 24 26 3 0.21 43 41 4.8 e39 e7 e0.74 25 24 3 0.21 52 34 4.8 e49 e10 e1.3 26 23 4 0.22 34 41 3.8 e40 e18 e1.9 27 23 4 0.24 30 48 3.9 e35 e26 e2.5 28 39 4 0.42 56 80 19 e33 e35 e3.1 29 38 4 0.41 54 35 5.2 e31 e50 e4.2 30 26 4 0.28 53 39 6.4 e29 e48 e3.8 31 36 34 6.9 73 42 9.2 --- --- --- TOTAL 1001 --- 44.48 1525 --- 518.03 1755 --- 904.94 YEAR 29617 61221.99 e Estimated 115 RIO GRANDE DE ARECIBO BASIN 50026025 RIO CAONILLAS AT PASO PALMA, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT Sus- Suspnd. pended Sus- sedi- Instan- sedi- pended ment, taneous ment sedi- sieve dis- concen- ment diametr Date Time charge, tration load, percent cfs mg/L tons/d <.062mm (00061) (80154) (80155) (70331) NOV 08... 1704 1220 754 2480 84 MAR 29... 1910 1400 6620 25000 76 APR 23... 1650 1900 8070 41400 76 27... 2034 2770 8300 62000 75 WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 PARTICLE SIZE DISTRIBUTION OF SUSPENDED SEDIMENT Sus- Suspnd. Suspnd. Suspnd. Suspnd. Suspnd. Suspnd. Suspnd. Suspnd. Suspnd. pended Sus- sedi- sedi- sedi- sedi- sedi- sedi- sedi- sedi- sedi- Instan- sedi- pended ment, ment, ment, ment, ment, ment, ment, ment, ment, taneous ment sedi- falldia falldia falldia falldia falldia sieve sieve sieve sieve dis- concen- ment nat wat nat wat nat wat nat wat nat wat diametr diametr diametr diametr Date Time charge, tration load, percent percent percent percent percent percent percent percent percent cfs mg/L tons/d <.002mm <.004mm <.008mm <.016mm <.031mm <.062mm <.125mm <.25mm <.5 mm (00061) (80154) (80155) (70326) (70327) (70328) (70329) (70330) (70331) (70332) (70333) (70334) NOV 08... 0819 4300 12200 142000 17 22 28 37 47 59 84 98 100 Suspnd. sedi- ment, sieve diametr Date percent <1 mm (70335) NOV 08... 100 116 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 Lago Caonillas, and 3.3 mi (5.3 km) northwest of Jayuya Plaza. DRAINAGE AREA.--40.4 mi2 (104.6 km2). PERIOD OF RECORD.--Water years 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 TURBID- FECAL FECAL SPECIF. PH, ITY, DIS- COD, COLI- STREP- HARD- INSTAN- CONDUC- WATER, WAT UNF SOLVED HIGH FORM, TOCOCCI NESS, TANEOUS TANCE, UNFLTRD TEMPER- LAB, DIS- OXYGEN, LEVEL, M-FC KF WATER, CALCIUM DIS- WAT UNF FIELD, ATURE, HACH SOLVED PERCENT WATER, 0.7U MF MF, UNFLTRD WATER, DATE TIME CHARGE, US/CM STD WATER, 2100AN OXYGEN, OF SAT- UNFLTRD COL/ COL/ MG/L AS FLTRD, CFS 25 DEGC UNITS DEG C NTU MG/L URATION MG/L 100 ML 100 ML CACO3 MG/L (00061) (00095) (00400) (00010) (99872) (00300) (00301) (00340) (31625) (31673) (00900) (00915) DEC 17... 0945 81 198 7.1 21.9 27 8.4 100 <10 4600 2100 71 19.0 MAR 12... 1120 110 187 7.0 21.7 29 8.3 99 <10 4900 5900 -- -- SEP 17... 0845 48 191 7.1 23.8 24 8.3 101 10 E1730 490 73 19.4 ANC, RESIDUE RESIDUE WAT UNF WATER, TOTAL MAGNES- POTAS- FIXED CHLOR- FLUOR- FLTRD, AT 105 IUM, SODIUM, SODIUM SIUM, END PT, SULFIDE SULFATE IDE, IDE, SILICA, SUM OF RESIDUE DEG. C, WATER, WATER, ADSORP- WATER, FIELD, WATER WATER, WATER, WATER, WATER, CONSTI- WATER, SUS- DATE FLTRD, FLTRD, TION FLTRD, MG/L AS UNFLTRD FLTRD, FLTRD, FLTRD, FLTRD, TUENTS FLTRD, PENDED, MG/L MG/L RATIO MG/L CACO3 MG/L MG/L MG/L MG/L MG/L MG/L TONS/D MG/L (00925) (00930) (00931) (00935) (00410) (00745) (00945) (00940) (00950) (00955) (70301) (70302) (00530) DEC 17... 5.76 9.47 .5 1.73 63 <1.0 11.5 9.66 E.1 22.4 117 25.6 30 MAR 12... -- -- -- -- 54 -- -- -- -- -- -- -- 32 SEP 17... 5.99 10.2 .5 1.65 80 <.1 11.8 9.71 E.07 23.1 130 16.6 <10 NITRITE AMMONIA CHROM- + + BARIUM, BORON, IUM, COPPER, IRON, LEAD, NITRITE NITRATE AMMONIA ORG-N, PHOS- WATER, WATER, WATER, WATER, WATER, WATER, WATER, WATER WATER, WATER, PHORUS, ARSENIC UNFLTRD UNFLTRD CADMIUM UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD WATER, WATER RECOV- RECOV- WATER, RECOV- RECOV- RECOV- RECOV- DATE MG/L MG/L MG/L MG/L UNFLTRD UNFLTRD ERABLE, ERABLE, UNFLTRD ERABLE, ERABLE, ERABLE, ERABLE, AS N AS N AS N AS N MG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L (00615) (00630) (00610) (00625) (00665) (01002) (01007) (01022) (01027) (01034) (01042) (01045) (01051) DEC 17... <.01 .880 .04 .30 .06 <2 23.3 20 <.1 <.8 M 560 <1 MAR 12... .01 1.30 .02 .20 .10 -- -- -- -- -- -- -- -- SEP 17... .01 .590 .02 <.20 .06 <2 24.3 <20 <.1 <.8 M 400 <1 MANGAN- PHEN- ESE, MERCURY SILVER, ZINC, OLIC WATER, WATER, SELEN- WATER, WATER, COM- UNFLTRD UNFLTRD IUM, UNFLTRD UNFLTRD CYANIDE POUNDS, MBAS, RECOV- RECOV- WATER, RECOV- RECOV- WATER WATER, WATER, DATE ERABLE, ERABLE, UNFLTRD ERABLE, ERABLE, UNFLTRD UNFLTRD UNFLTRD UG/L UG/L UG/L UG/L UG/L MG/L UG/L MG/L (01055) (71900) (01147) (01077) (01092) (00720) (32730) (38260) DEC 17... 46.8 <.01 <2 <.3 <20 <.01 -- <.05 MAR 12... -- -- -- -- -- -- -- -- SEP 17... 22.6 <.01 <2 <.3 E20 <.01 <16 <.05 < -- Less than E -- Estimated value M -- Presence verified, not quantified 117 RIO GRANDE DE ARECIBO BASIN 50026200 RIO CAONILLAS BLW LAGO CAONILLAS TUNNEL, PR LOCATION.--Lat 18°17'57", long 66°38'36", Hydrologic Unit 21010001, on left bank at Río Caonillas Tunnel 1.6 mi (2.6 km) downstream of Lago Caonillas Dam, 3.1 mi (5.0 km) southeast from Central Hidroelétrica of Lago Dos Bocas, 2.6 mi (4.2 km) west from Escuela Segunda Unidad de Mameyes. DRAINAGE AREA.--Indeterminate. WATER-DISCHARGE RECORDS PERIOD OF RECORD.--December 2000 to current year. GAGE.--Water-stage recorder. Elevation of gage 295 ft (90 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 2001 TO SEPTEMBER 2002 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 263 55 169 49 57 53 98 538 84 145 62 117 2 169 332 263 57 56 53 103 333 84 145 66 68 3 52 175 304 52 56 53 100 362 84 130 64 131 4 98 78 274 67 55 53 99 480 84 133 63 66 5 37 43 282 60 55 53 101 477 84 130 63 65 6 115 23 270 61 77 51 105 476 84 137 61 61 7 68 7.7 316 61 57 49 105 474 85 123 60 57 8 297 256 288 64 49 50 119 440 85 125 60 56 9 263 67 307 57 49 62 106 342 85 126 61 119 10 115 26 323 72 155 72 99 439 85 119 61 116 11 77 15 340 91 58 72 220 258 196 134 65 122 12 36 11 254 108 58 71 234 330 127 128 66 118 13 47 8.8 59 71 58 70 277 353 262 128 188 122 14 50 9.1 59 83 58 70 147 156 229 133 194 95 15 72 7.9 56 115 58 63 148 471 85 147 256 119 16 90 6.4 56 268 58 53 281 477 84 126 251 120 17 85 5.5 132 291 58 53 288 291 137 129 91 83 18 36 5.5 59 128 57 54 91 117 135 152 126 64 19 57 13 196 210 62 54 159 132 164 189 116 61 20 40 85 151 200 67 53 137 197 146 123 122 61 21 40 169 70 205 62 54 106 135 145 123 228 133 22 40 181 65 252 56 70 159 137 129 123 102 64 23 77 179 70 e132 55 74 252 265 120 130 117 63 24 71 198 136 e70 55 74 238 189 141 121 116 67 25 33 125 71 e64 54 85 164 179 140 59 59 126 26 33 213 64 e61 54 88 119 84 143 59 83 134 27 34 205 87 e60 54 83 532 133 143 59 123 200 28 40 183 46 e58 55 83 1140 129 146 59 128 108 29 42 186 46 e57 --- 84 791 258 145 60 118 82 30 58 190 46 e57 --- 84 970 155 158 59 55 61 31 141 --- 49 57 --- 84 --- 83 --- 59 53 --- TOTAL 2676 3058.9 4908 3238 1703 2025 7488 8890 3819 3613 3278 2859 MEAN 86.3 102 158 104 60.8 65.3 250 287 127 117 106 95.3 MAX 297 332 340 291 155 88 1140 538 262 189 256 200 MIN 33 5.5 46 49 49 49 91 83 84 59 53 56 AC-FT 5310 6070 9740 6420 3380 4020 14850 17630 7570 7170 6500 5670 CFSM 1.70 2.01 3.12 2.06 1.20 1.29 4.91 5.65 2.51 2.29 2.08 1.88 IN. 1.96 2.24 3.59 2.37 1.25 1.48 5.48 6.51 2.80 2.65 2.40 2.09 STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 2001 - 2002, BY WATER YEAR (WY) MEAN 86.3 102 158 86.5 53.5 64.1 169 209 137 122 135 119 MAX 86.3 102 158 104 60.8 65.3 250 287 148 127 164 143 (WY) 2002 2002 2002 2002 2002 2002 2002 2002 2001 2001 2001 2001 MIN 86.3 102 158 68.5 46.1 63.0 88.8 132 127 117 106 95.3 (WY) 2002 2002 2002 2001 2001 2001 2001 2001 2002 2002 2002 2002 SUMMARY STATISTICS FOR 2001 CALENDAR YEAR FOR 2002 WATER YEAR WATER YEARS 2001 - 2002 ANNUAL TOTAL 40491.9 47555.9 ANNUAL MEAN 111 130 130 HIGHEST ANNUAL MEAN 130 2002 LOWEST ANNUAL MEAN 130 2002 HIGHEST DAILY MEAN 340 Dec 11 1140 Apr 28 1140 Apr 28 2002 LOWEST DAILY MEAN 5.5 Nov 17 5.5 Nov 17 5.5 Nov 17 2001 ANNUAL SEVEN-DAY MINIMUM 7.7 Nov 12 7.7 Nov 12 7.7 Nov 12 2001 MAXIMUM PEAK FLOW 1990 Apr 27 1990 Apr 27 2002 MAXIMUM PEAK STAGE 7.45 Apr 27 7.45 Apr 27 2002 ANNUAL RUNOFF (AC-FT) 80320 94330 94390 ANNUAL RUNOFF (CFSM) 2.18 2.56 2.56 ANNUAL RUNOFF (INCHES) 29.65 34.82 34.85 10 PERCENT EXCEEDS 196 264 264 50 PERCENT EXCEEDS 104 87 87 90 PERCENT EXCEEDS 27 52 52 e Estimated 118 RIO GRANDE DE ARECIBO BASIN 50026200 RIO CAONILLAS BLW LAGO CAONILLAS TUNNEL, PR--Continued O N D 2001 J F M A M J J A S 2002 1 2 5 10 10 20 50 100 100 200 500 1000 1000 2000 5000 10,000 DISCHARGE, IN CUBIC FEET PER SECOND 119 RIO GRANDE DE ARECIBO BASIN 50026200 RIO CAONILLAS BLW LAGO CAONILLAS TUNNEL, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--December 2000 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: January 2001 to current year. INSTRUMENTATION.--USDH-48 and automatic sediment samplers since 2000. REMARKS.-- Sediment samples were collected by a local observer on a weekly basis. During high flow events sediment samples were collected with automatic sediment sampler. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATION: Maximum daily mean, 268 mg/L November 8, 2001; Minimum daily mean, <1 mg/L several days during Water Year 2001. SEDIMENT LOADS: Maximum daily mean, 723 tons (656 tonnes) April 28, 2002; Minimum daily mean, 0.02 ton (0.02 tonne) several days during Water Year 2001. EXTREMES FOR WATER YEAR 2001.-- SEDIMENT CONCENTRATION: Maximum daily mean, e77 mg/L May 10, 2001; Minimum daily mean,<1 mg/L several days. SEDIMENT LOADS: Maximum daily mean, e60 tons (e54 tonnes) May 10, 2001; Minimum daily mean, 0.02 ton (0.02 tonne) several days. EXTREMES FOR CURRENT YEAR 2002.-- SEDIMENT CONCENTRATION: Maximum daily mean, 268 mg/L November 8, 2001; Minimum daily mean, 1 mg/L several days. SEDIMENT LOADS: Maximum daily mean, 723 tons (656 tonnes) April 28, 2002; Minimum daily mean, 0.15 ton (0.14 tonne) several days. SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2000 TO SEPTEMBER 2001 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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 FEBRUARY MARCH 1 21 e1 e0.05 71 3 1.0 70 1 0.55 2 21 e1 e0.05 82 3 1.2 29 1 0.11 3 21 e1 e0.05 74 3 1.1 39 3 0.36 4 69 e1 e0.32 80 3 1.3 31 <1 0.02 5 58 e1 e0.32 78 3 1.3 26 1 0.04 6 59 e1 e0.32 64 3 1.0 142 2 1.1 7 21 e1 e0.05 20 2 0.10 32 1 0.09 8 35 e2 e0.17 24 1 0.09 27 1 0.07 9 113 e4 e1.6 23 1 0.07 97 2 0.68 10 94 e3 e1.3 21 1 0.06 27 1 0.07 11 64 e1 e0.32 73 2 0.65 25 1 0.07 12 121 e4 e1.6 64 2 0.46 140 2 1.1 13 164 e3 e1.9 24 1 0.07 29 1 0.08 14 157 e3 e1.9 24 1 0.06 29 1 0.08 15 92 e2 e0.90 53 2 0.73 67 1 0.38 16 66 e1 e0.32 22 1 0.05 31 1 0.06 17 58 e1 e0.32 40 1 0.16 29 1 0.04 18 67 e1 e0.32 67 1 0.18 29 <1 0.02 19 64 1 0.32 66 1 0.30 73 1 0.40 20 81 1 0.35 26 1 0.07 26 1 0.07 21 79 2 0.68 25 <1 0.03 124 1 0.64 22 104 2 0.91 35 4 0.48 e35 e1 e0.07 23 23 2 0.12 24 5 0.31 e35 e2 e0.16 24 112 4 1.6 57 4 0.46 e40 e2 e0.21 25 54 3 0.68 27 1 0.07 28 1 0.08 26 32 3 0.27 28 1 0.07 155 2 0.81 27 28 2 0.15 69 2 0.57 153 1 0.62 28 102 4 1.7 31 1 0.05 64 1 0.45 29 30 2 0.16 --- --- --- 114 1 0.57 30 82 3 1.3 --- --- --- 142 1 0.56 31 32 2 0.17 --- --- --- e64 <1 e0.02 TOTAL 2124 --- 20.22 1292 --- 11.99 1952 --- 9.58 < Actual value is known to be less than the value shown 120 RIO GRANDE DE ARECIBO BASIN 50026200 RIO CAONILLAS BLW LAGO CAONILLAS TUNNEL, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2000 TO SEPTEMBER 2001 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) APRIL MAY JUNE 1 e64 e1 e0.40 e80 e3 e1.5 169 13 6.4 2 e108 e2 e1.2 e180 e4 e2.1 152 13 5.5 3 159 3 1.9 e170 e5 e2.9 77 13 3.3 4 105 1 0.50 e80 e5 e3.5 136 13 5.0 5 81 1 0.38 e83 e5 e3.5 154 13 5.7 6 71 1 0.40 e54 e1 e0.40 166 11 5.1 7 130 1 0.77 e26 e44 e25 174 10 5.2 8 26 <1 0.02 e82 e53 e22 149 13 5.7 9 68 1 0.40 e157 e67 e45 147 13 5.6 10 e141 e3 e1.5 e254 e77 e60 137 11 4.9 11 e170 e2 e0.83 e277 e73 e56 154 12 5.7 12 106 2 0.69 e29 e9 e1.9 151 12 5.7 13 e30 e1 e0.08 e27 e9 e1.9 107 11 3.8 14 e107 e2 e0.62 e107 e22 e12 157 12 5.8 15 e61 e1 e0.34 85 30 10 152 11 5.6 16 71 1 0.42 74 19 7.0 151 11 5.5 17 e118 e2 e1.1 129 29 14 157 11 5.8 18 e138 e3 e1.5 107 24 11 164 11 5.9 19 e147 e3 e1.7 167 31 19 167 11 6.1 20 e148 e3 e1.3 168 31 19 159 12 5.8 21 e29 e1 e0.08 122 17 7.4 150 11 5.5 22 e81 e2 e0.79 126 16 7.2 149 11 5.5 23 e81 e3 e1.4 172 19 11 147 11 5.3 24 e27 e1 e0.20 167 18 10 149 11 5.5 25 e144 e4 e2.2 172 18 9.8 159 11 5.8 26 e31 e1 e0.24 148 18 8.8 156 11 5.6 27 e30 e2 e0.38 154 18 9.2 141 11 5.2 28 e86 e3 e2.0 176 19 11 143 11 5.4 29 e79 e4 e2.4 159 19 9.7 113 10 3.9 30 e26 e2 e0.29 177 19 11 142 11 5.2 31 --- --- --- 178 19 11 --- --- --- TOTAL 2663 --- 26.03 4087 --- 423.80 4429 --- 161.0 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) JULY AUGUST SEPTEMBER 1 67 9 2.3 153 13 5.7 160 12 6.3 2 153 11 5.6 157 13 5.9 155 11 6.1 3 190 11 6.3 192 8 4.1 154 11 5.4 4 195 12 6.8 118 8 2.5 96 13 3.8 5 190 11 6.3 66 8 1.4 186 13 7.9 6 225 12 7.4 164 12 6.0 130 13 5.4 7 102 10 3.8 107 10 3.8 150 8 4.6 8 116 11 4.5 159 11 5.9 39 6 0.64 9 133 11 4.8 162 12 6.0 94 7 3.2 10 151 11 5.5 151 13 5.7 231 10 8.7 11 163 12 6.0 139 13 5.3 137 7 3.9 12 158 11 5.8 128 13 4.8 136 8 4.2 13 153 11 5.4 126 13 4.8 268 10 7.7 14 59 9 1.9 111 13 4.4 112 4 1.2 15 64 9 2.2 159 13 6.0 98 4 1.0 16 76 10 2.7 211 14 8.3 59 4 0.56 17 74 12 2.6 230 13 9.1 31 3 0.28 18 132 12 4.4 106 13 4.3 57 3 0.47 19 93 13 3.7 105 13 4.2 59 3 0.48 20 150 13 5.6 182 13 7.7 124 5 3.1 21 86 12 3.3 104 10 3.9 89 3 0.72 22 35 11 1.0 144 10 5.2 146 3 1.2 23 50 14 2.0 322 12 12 246 9 6.9 24 110 16 4.7 133 10 4.9 121 37 15 25 101 13 4.1 185 11 7.2 136 29 15 26 161 13 6.0 185 11 7.3 163 32 21 27 151 13 5.7 211 11 8.3 216 32 26 28 170 13 6.4 251 11 9.3 265 33 32 29 131 12 4.8 196 11 7.5 293 36 37 30 142 13 5.4 219 11 8.5 143 26 15 31 152 13 5.7 199 11 7.1 --- --- --- TOTAL 3933 --- 142.7 5075 --- 187.1 4294 --- 244.75 e Estimated 121 RIO GRANDE DE ARECIBO BASIN 50026200 RIO CAONILLAS BLW LAGO CAONILLAS TUNNEL, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) OCTOBER NOVEMBER DECEMBER 1 263 37 36 55 12 1.8 169 15 8.3 2 169 24 21 332 12 11 263 15 13 3 52 12 1.7 175 12 5.7 304 16 15 4 98 18 9.7 78 12 2.5 274 15 13 5 37 12 1.2 43 12 1.4 282 16 14 6 115 20 14 23 12 0.73 270 15 13 7 68 16 6.2 7.7 12 0.25 316 16 15 8 297 38 45 256 268 264 288 15 14 9 263 37 38 67 71 18 307 16 15 10 115 21 11 26 12 0.83 323 16 15 11 77 20 6.9 15 12 0.48 340 16 16 12 36 16 1.6 11 12 0.35 254 15 12 13 47 16 2.0 8.8 12 0.28 59 12 1.9 14 50 16 2.2 9.1 12 0.29 59 12 1.9 15 72 19 6.7 7.9 12 0.25 56 12 1.8 16 90 21 9.5 6.4 12 0.21 56 12 1.8 17 85 20 8.8 5.5 12 0.18 132 13 5.9 18 36 16 1.5 5.5 12 0.18 59 12 1.9 19 57 17 4.4 13 12 0.41 196 16 9.6 20 40 15 1.6 85 14 4.6 151 13 6.0 21 40 15 1.6 169 19 11 70 12 2.2 22 40 15 1.6 181 20 12 65 11 1.9 23 77 19 7.1 179 20 12 70 10 1.8 24 71 18 6.7 198 20 13 136 12 5.6 25 33 14 1.2 125 17 7.8 71 9 1.7 26 33 14 1.2 213 21 15 64 6 0.97 27 34 14 1.2 205 21 14 87 8 2.7 28 40 13 1.4 183 20 12 46 7 0.86 29 42 13 1.5 186 19 12 46 6 0.69 30 58 16 4.5 190 19 12 46 4 0.46 31 141 24 17 --- --- --- 49 3 0.39 TOTAL 2676 --- 274.0 3058.9 --- 434.24 4908 --- 213.37 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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 FEBRUARY MARCH 1 49 3 0.40 57 1 0.15 53 4 0.64 2 57 3 0.46 56 1 0.15 53 6 0.80 3 52 3 0.42 56 1 0.15 53 5 0.72 4 67 3 0.54 55 1 0.15 53 4 0.64 5 60 4 0.65 55 1 0.15 53 4 0.56 6 61 10 1.6 77 1 0.30 51 3 0.46 7 61 8 1.3 57 2 0.34 49 3 0.37 8 64 7 1.2 49 3 0.34 50 2 0.30 9 57 19 2.9 49 3 0.38 62 4 0.68 10 72 20 3.7 155 6 3.6 72 7 1.3 11 91 14 3.5 58 4 0.63 72 10 1.9 12 108 9 2.5 58 4 0.63 71 13 2.4 13 71 4 0.85 58 4 0.65 70 16 3.1 14 83 4 1.0 58 6 0.91 70 22 4.3 15 115 4 1.6 58 8 1.2 63 29 4.8 16 268 6 4.3 58 10 1.6 53 26 3.7 17 291 6 4.7 58 12 1.8 53 18 2.5 18 128 6 2.1 57 13 2.0 54 12 1.8 19 210 6 3.4 62 12 2.0 54 8 1.1 20 200 6 3.2 67 3 0.63 53 2 0.32 21 205 6 3.2 62 2 0.33 54 2 0.25 22 252 e6 e3.2 56 2 0.30 70 1 0.27 23 e132 e9 e2.5 55 2 0.30 74 1 0.24 24 e70 e4 e0.85 55 2 0.30 74 1 0.25 25 e64 e4 e0.85 54 2 0.29 85 2 0.55 26 e61 e4 e0.85 54 2 0.29 88 4 0.84 27 e60 e4 e0.85 54 2 0.29 83 4 0.83 28 e58 e1 e0.15 55 2 0.30 83 6 1.4 29 e57 e1 e0.15 --- --- --- 84 9 2.1 30 e57 e1 e0.16 --- --- --- 84 12 2.8 31 57 1 0.15 --- --- --- 84 23 5.3 TOTAL 3238 --- 53.23 1703 --- 20.16 2025 --- 47.22 122 RIO GRANDE DE ARECIBO BASIN 50026200 RIO CAONILLAS BLW LAGO CAONILLAS TUNNEL, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) APRIL MAY JUNE 1 98 22 5.9 538 138 202 84 19 4.4 2 103 15 4.2 333 81 72 84 20 4.5 3 100 14 3.8 362 25 26 84 21 4.7 4 99 30 8.0 480 19 24 84 17 3.9 5 101 48 13 477 27 35 84 12 2.7 6 105 65 18 476 27 35 84 7 1.5 7 105 78 22 474 27 35 85 5 1.1 8 119 66 21 440 25 31 85 5 1.1 9 106 24 7.0 342 19 23 85 5 1.1 10 99 16 4.2 439 26 32 85 5 1.1 11 220 11 6.2 258 15 16 196 9 6.9 12 234 4 2.6 330 34 41 127 7 3.5 13 277 9 8.0 353 46 55 262 11 10 14 147 11 4.4 156 15 15 229 10 8.6 15 148 9 3.6 471 44 56 85 5 1.2 16 281 7 5.4 477 44 57 84 5 1.1 17 288 12 11 291 22 26 137 5 1.8 18 91 13 3.3 117 6 3.5 135 7 3.7 19 159 9 3.5 132 7 5.0 164 8 5.3 20 137 5 1.7 197 12 11 146 7 4.2 21 106 20 5.7 135 8 5.2 145 7 4.1 22 159 21 8.9 137 8 5.2 129 7 3.6 23 252 113 132 265 3 2.1 120 6 3.2 24 238 62 42 189 3 1.5 141 7 4.2 25 164 56 28 179 8 6.1 140 7 4.3 26 119 54 18 84 6 1.4 143 7 4.3 27 532 199 602 133 5 1.9 143 7 4.3 28 1140 230 723 129 5 1.7 146 7 4.2 29 791 260 678 258 4 2.8 145 7 4.4 30 970 251 721 155 12 6.2 158 8 5.1 31 --- --- --- 83 19 4.1 --- --- --- TOTAL 7488 --- 3115.4 8890 --- 838.7 3819 --- 114.1 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) JULY AUGUST SEPTEMBER 1 145 7 4.3 62 7 1.1 117 22 7.0 2 145 7 4.3 66 7 1.2 68 22 4.0 3 130 7 4.0 64 7 1.2 131 22 7.6 4 133 7 4.1 63 7 1.2 66 21 3.7 5 130 7 4.0 63 7 1.2 65 21 3.6 6 137 7 4.2 61 7 1.2 61 20 3.3 7 123 7 3.6 60 7 1.1 57 20 3.1 8 125 7 4.0 60 7 1.1 56 20 2.9 9 126 7 4.0 61 7 1.1 119 19 6.1 10 119 7 3.6 61 7 1.1 116 19 6.0 11 134 7 4.4 65 7 1.2 122 19 6.3 12 128 7 4.1 66 7 1.2 118 20 6.9 13 128 7 4.0 188 7 3.6 122 49 17 14 133 7 4.0 194 7 3.7 95 30 6.3 15 147 8 5.0 256 12 11 119 17 5.5 16 126 7 4.1 251 12 10 120 17 5.5 17 129 7 4.1 91 7 1.7 83 17 3.8 18 152 8 5.2 126 9 4.2 64 9 1.6 19 189 9 6.8 116 9 4.1 61 8 1.4 20 123 8 4.0 122 9 4.3 61 7 1.2 21 123 8 4.0 228 11 9.5 133 7 3.0 22 123 8 3.9 102 8 3.2 64 7 1.2 23 130 8 4.3 117 9 4.0 63 6 1.1 24 121 8 3.7 116 9 3.9 67 6 1.1 25 59 6 0.97 59 7 1.1 126 7 2.6 26 59 6 0.99 83 11 3.6 134 7 2.7 27 59 6 1.0 123 25 8.3 200 7 4.5 28 59 6 1.0 128 24 8.4 108 6 2.2 29 60 7 1.1 118 24 7.6 82 6 1.6 30 59 7 1.1 55 23 3.5 61 7 1.2 31 59 7 1.1 53 23 3.3 --- --- --- TOTAL 3613 --- 108.96 3278 --- 112.9 2859 --- 124.0 YEAR 47555.9 5456.28 e Estimated 123 RIO GRANDE DE ARECIBO BASIN 50026200 RIO CAONILLAS BLW LAGO CAONILLAS TUNNEL, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT Sus- Suspnd. pended Sus- sedi- Instan- sedi- pended ment, taneous ment sedi- sieve dis- concen- ment diametr Date Time charge, tration load, percent cfs mg/L tons/d <.063mm (00061) (80154) (80155) (70331) APR 27... 2141 1880 661 3360 85 28... 0541 1450 225 881 89 124 RIO GRANDE DE ARECIBO BASIN 50026400 RIO YUNES AT HWY 140 NEAR FLORIDA, PR LOCATION.--Lat 18°19'27', long 66°35'13", Hydrologic Unit 21010002, on left bank, 600 ft downstream from bridge on Highway 140, 3.1 mi (4.9 km) southwest from Florida Plaza, 2.4 mi (3.9 km) northwest from Escuela Segunda Unidad de Frontón, 1.9 mi (3.1 km) northeast from Escuela Segunda Unidad de Mameyes. DRAINAGE AREA.--13.9 mi2 (36.1 km2). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--June 2000 to current year. GAGE.--Water-stage recorder. Elevation of gage is 492 ft (150 m), from topographic map. REMARKS.--Records fair except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. Discharge, cubic feet per second WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 9.8 107 23 24 15 16 55 197 25 12 54 22 2 9.6 53 23 23 14 16 28 166 25 12 34 77 3 26 20 30 22 14 16 13 101 28 12 28 62 4 17 16 30 22 15 16 11 74 28 12 171 130 5 15 15 25 37 14 15 85 63 32 12 47 104 6 11 14 23 44 14 14 78 60 25 18 26 50 7 10 32 22 38 15 14 55 51 21 16 20 33 8 22 1660 20 30 13 16 101 46 20 11 18 27 9 28 325 19 27 13 14 60 44 19 47 55 25 10 192 155 19 24 12 26 36 40 19 e27 31 22 11 77 88 19 23 11 52 29 38 18 e18 147 21 12 33 68 25 22 11 40 23 36 18 e30 52 19 13 21 56 26 21 11 19 19 34 19 e15 26 18 14 19 51 30 20 11 16 18 33 18 e14 28 26 15 16 45 25 20 10 14 20 53 16 e13 23 48 16 14 40 70 21 10 14 26 36 16 12 20 39 17 14 37 56 20 10 17 24 31 18 e13 19 25 18 14 35 43 20 9.9 13 92 30 20 e15 18 192 19 12 33 33 19 40 14 52 28 17 e11 18 150 20 12 32 28 19 22 12 88 26 16 11 17 58 21 12 30 33 18 16 11 101 25 16 e11 16 36 22 11 29 35 18 16 11 43 23 15 e16 18 30 23 11 28 128 18 18 10 254 22 14 13 33 27 24 11 31 80 22 18 9.7 258 21 15 11 24 31 25 11 28 45 17 17 9.0 193 20 14 e10 21 30 26 11 26 36 16 20 8.9 134 19 14 e10 17 29 27 11 27 32 16 18 8.9 156 20 16 10 16 27 28 63 28 30 17 17 16 107 19 14 19 15 24 29 28 28 28 17 --- 14 267 18 13 e15 21 23 30 16 25 26 16 --- 11 151 17 13 e10 27 21 31 12 --- 25 16 --- 21 --- 19 --- 15 31 --- TOTAL 769.4 3162 1087 687 424.9 504.5 2577 1410 562 471 1091 1426 MEAN 24.8 105 35.1 22.2 15.2 16.3 85.9 45.5 18.7 15.2 35.2 47.5 MAX 192 1660 128 44 40 52 267 197 32 47 171 192 MIN 9.6 14 19 16 9.9 8.9 11 17 13 10 15 18 AC-FT 1530 6270 2160 1360 843 1000 5110 2800 1110 934 2160 2830 CFSM 1.77 7.53 2.51 1.58 1.08 1.16 6.14 3.25 1.34 1.09 2.52 3.40 IN. 2.05 8.41 2.89 1.83 1.13 1.34 6.85 3.75 1.49 1.25 2.90 3.79 STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 2000 - 2002, BY WATER YEAR (WY) MEAN 32.9 70.6 24.4 16.4 12.2 11.6 49.4 35.0 14.0 14.8 22.0 33.1 MAX 41.1 105 35.1 22.2 15.2 16.3 85.9 45.5 18.7 20.9 35.2 47.5 (WY) 2001 2002 2002 2002 2002 2002 2002 2002 2002 2001 2002 2002 MIN 24.8 35.8 13.8 10.7 9.14 7.00 12.9 24.4 9.34 8.39 11.0 25.8 (WY) 2002 2001 2001 2001 2001 2001 2001 2001 2001 2000 2000 2000 SUMMARY STATISTICS FOR 2001 CALENDAR YEAR FOR 2002 WATER YEAR WATER YEARS 2000 - 2002 ANNUAL TOTAL 9293.2 14171.8 ANNUAL MEAN 25.5 38.8 29.1 HIGHEST ANNUAL MEAN 38.8 2002 LOWEST ANNUAL MEAN 19.3 2001 HIGHEST DAILY MEAN 1660 Nov 8 1660 Nov 8 1660 Nov 8 2001 LOWEST DAILY MEAN 5.3 Apr 4 8.9 Mar 26 4.7 Aug 12 2000 ANNUAL SEVEN-DAY MINIMUM 5.9 Mar 29 9.8 Mar 21 5.2 Aug 12 2000 MAXIMUM PEAK FLOW 5070 Nov 8 5070 Nov 8 2001 MAXIMUM PEAK STAGE 12.37 Nov 8 12.37 Nov 8 2001 INSTANTANEOUS LOW FLOW 8.2 Mar 28 4.4 Aug 12 2000 ANNUAL RUNOFF (AC-FT) 18430 28110 21060 ANNUAL RUNOFF (CFSM) 1.82 2.78 2.08 ANNUAL RUNOFF (INCHES) 24.71 37.68 28.23 10 PERCENT EXCEEDS 44 65 52 50 PERCENT EXCEEDS 11 21 16 90 PERCENT EXCEEDS 6.5 12 7.2 e Estimated 125 RIO GRANDE DE ARECIBO BASIN 50026400 RIO YUNES AT HWY 140 NEAR FLORIDA, PR--Continued O N D 2001 J F M A M J J A S 2002 1 2 5 10 10 20 50 100 100 200 500 1000 1000 2000 5000 10,000 DISCHARGE, IN CUBIC FEET PER SECOND 126 RIO GRANDE DE ARECIBO BASIN 50026400 RIO YUNES AT HWY 140 NEAR FLORIDA, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--June 2000 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: June 2000 to current year. INSTRUMENTATION.--USDH-48 and automatic sediment samplers since 2000. REMARKS.--Sediment samples were collected by a local observer on a weekly basis. During high flow events sediment samples were collected with automatic sediment sampler. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATION: Maximum daily mean, 4,940 mg/L November 8, 2001; Minimum daily mean, 1 mg/L several days during Water Year 2001. SEDIMENT LOADS: Maximum daily mean, 30,700 tons (27,850 tonnes) November 8, 2001; Minimum daily mean, 0.02 ton (0.02 tonne) several days during Water Year 2001. EXTREMES FOR WATER YEAR 2001.-- SEDIMENT CONCENTRATION: Maximum daily mean, 740 mg/L November 1, 2000; Minimum daily mean, 1 mg/L several days. SEDIMENT LOADS: Maximum daily mean, 2,580 tons (2,340 tonnes) August 3, 2001; Minimum daily mean, 0.02 ton (0.02 tonne) several days. EXTREMES FOR CURRENT YEAR 2002.-- SEDIMENT CONCENTRATION: Maximum daily mean, 4,940 mg/L November 8, 2001; Minimum daily mean, 2 mg/L several days. SEDIMENT LOADS: Maximum daily mean, 30,700 tons (27,850 tonnes) November 8, 2001; Minimum daily mean, 0.07 ton (0.06 tonne) several days. SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2000 TO SEPTEMBER 2001 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) OCTOBER NOVEMBER DECEMBER 1 13 4 0.14 194 740 1190 17 10 0.47 2 20 4 0.21 97 196 65 16 10 0.42 3 42 72 24 122 100 53 15 8 0.35 4 34 30 4.5 50 12 1.6 15 7 0.30 5 19 9 0.48 39 15 1.6 15 6 0.24 6 16 9 0.39 34 19 1.7 14 5 0.19 7 15 9 0.36 31 22 1.8 14 4 0.15 8 17 8 0.38 30 16 1.3 13 3 0.11 9 15 8 0.33 29 9 0.71 13 2 0.09 10 16 8 0.35 27 4 0.26 13 2 0.07 11 72 163 126 26 3 0.23 13 2 0.05 12 31 12 1.5 26 4 0.24 14 1 0.04 13 17 6 0.29 e25 e4 e0.25 15 10 0.38 14 15 6 0.24 24 4 0.25 14 11 0.42 15 15 6 0.24 24 3 0.20 18 4 0.18 16 31 28 4.3 23 2 0.13 19 3 0.16 17 37 44 9.5 22 1 0.07 20 3 0.16 18 35 57 7.6 21 2 0.09 16 3 0.13 19 218 464 1340 21 2 0.12 e13 e3 e0.10 20 62 84 20 21 2 0.14 e12 e2 e0.08 21 28 33 2.5 22 3 0.17 12 2 0.05 22 25 27 1.8 22 3 0.16 12 1 0.04 23 86 244 148 20 2 0.13 11 2 0.06 24 70 91 24 19 2 0.11 11 3 0.08 25 38 20 2.1 18 3 0.15 11 3 0.10 26 27 19 1.4 19 4 0.20 14 9 0.63 27 23 20 1.2 18 5 0.24 16 15 0.76 28 22 18 1.1 17 6 0.28 11 7 0.23 29 20 16 0.86 17 5 0.25 11 5 0.14 30 119 303 241 17 7 0.30 10 9 0.24 31 75 148 33 --- --- --- 10 13 0.35 TOTAL 1273 --- 1997.77 1075 --- 1320.68 428 --- 6.77 127 RIO GRANDE DE ARECIBO BASIN 50026400 RIO YUNES AT HWY 140 NEAR FLORIDA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2000 TO SEPTEMBER 2001 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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 FEBRUARY MARCH 1 9.9 17 0.46 9.7 9 0.24 8.6 13 0.30 2 9.7 21 0.56 8.8 7 0.17 8.4 15 0.33 3 9.8 26 0.68 8.1 6 0.14 7.9 13 0.28 4 9.1 30 0.73 7.5 6 0.11 7.7 11 0.24 5 8.8 38 0.90 7.3 5 0.09 7.7 10 0.20 6 8.7 56 1.3 7.3 4 0.08 7.4 8 0.16 7 8.6 58 1.3 7.2 4 0.08 7.1 7 0.14 8 8.5 56 1.3 6.9 5 0.09 6.7 7 0.12 9 8.3 55 1.2 7.0 5 0.09 6.5 6 0.10 10 8.4 54 1.2 6.9 5 0.09 6.1 6 0.09 11 8.0 52 1.1 9.1 5 0.12 6.0 5 0.09 12 7.9 51 1.1 9.1 5 0.12 6.0 5 0.08 13 8.0 48 1.0 9.2 5 0.12 6.2 5 0.09 14 8.4 46 1.0 7.4 4 0.09 6.6 6 0.10 15 8.8 44 1.0 8.1 4 0.09 6.0 6 0.09 16 7.9 40 0.86 7.9 4 0.08 5.9 7 0.11 17 7.8 30 0.62 8.2 4 0.09 5.7 10 0.15 18 7.2 18 0.35 7.0 4 0.08 5.6 13 0.19 19 6.9 9 0.16 6.9 4 0.08 5.6 16 0.24 20 6.7 7 0.13 6.7 4 0.07 6.6 19 0.34 21 6.8 6 0.11 7.4 6 0.14 7.2 22 0.43 22 6.7 5 0.09 23 32 2.1 7.2 25 0.50 23 6.9 4 0.08 11 22 0.67 9.0 28 0.68 24 6.8 3 0.06 12 16 0.51 11 25 0.75 25 6.6 2 0.04 15 11 0.45 9.6 20 0.51 26 7.0 4 0.07 12 7 0.22 6.5 15 0.27 27 11 3 0.10 9.8 8 0.22 6.6 14 0.26 28 23 29 2.0 9.3 11 0.27 6.8 14 0.26 29 45 72 16 --- --- --- 7.1 13 0.26 30 31 33 3.7 --- --- --- 5.9 13 0.20 31 12 12 0.38 --- --- --- 5.9 9 0.14 TOTAL 330.2 --- 39.58 255.8 --- 6.70 217.1 --- 7.70 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) APRIL MAY JUNE 1 5.7 5 0.07 13 21 0.73 12 13 0.40 2 5.7 2 0.03 9.0 15 0.36 9.7 9 0.23 3 5.7 5 0.08 7.9 12 0.25 8.7 5 0.13 4 5.3 9 0.13 7.4 9 0.19 12 4 0.12 5 13 21 1.2 7.1 9 0.17 8.6 2 0.05 6 21 31 3.3 75 236 337 8.0 3 0.06 7 13 14 0.62 130 330 359 7.1 3 0.07 8 7.3 4 0.08 55 101 50 7.0 4 0.07 9 6.9 2 0.05 50 42 9.1 6.9 4 0.07 10 6.4 4 0.07 75 200 89 6.6 4 0.07 11 7.0 6 0.11 56 22 5.6 6.4 4 0.07 12 6.4 7 0.13 24 4 0.25 6.2 4 0.08 13 6.4 9 0.15 16 4 0.15 6.3 4 0.08 14 8.3 8 0.18 18 3 0.17 7.0 2 0.04 15 5.9 7 0.11 15 3 0.13 6.3 1 0.02 16 5.9 6 0.10 12 3 0.10 6.2 1 0.02 17 5.7 6 0.09 11 3 0.09 14 13 0.80 18 5.4 6 0.08 11 3 0.09 33 66 17 19 5.4 6 0.08 17 3 0.12 18 28 2.0 20 5.5 5 0.08 9.8 2 0.07 8.5 6 0.14 21 8.5 5 0.12 8.8 2 0.05 7.2 4 0.08 22 17 24 2.2 8.5 4 0.10 6.6 4 0.06 23 25 34 2.6 8.7 9 0.22 6.4 3 0.05 24 14 19 0.73 7.6 10 0.20 6.8 3 0.05 25 22 32 4.8 7.2 10 0.19 7.9 2 0.05 26 72 192 65 7.0 10 0.19 7.0 2 0.04 27 40 57 7.3 28 54 11 6.7 2 0.04 28 15 29 1.2 27 12 1.6 8.0 3 0.06 29 11 19 0.55 11 6 0.18 13 3 0.10 30 12 14 0.53 9.4 8 0.21 12 2 0.08 31 --- --- --- 15 17 0.99 --- --- --- TOTAL 388.4 --- 91.77 757.4 --- 867.50 280.1 --- 22.13 128 RIO GRANDE DE ARECIBO BASIN 50026400 RIO YUNES AT HWY 140 NEAR FLORIDA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2000 TO SEPTEMBER 2001 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) JULY AUGUST SEPTEMBER 1 9.5 2 0.04 10 2 0.05 18 20 1.3 2 7.8 1 0.02 10 2 0.06 17 19 1.0 3 6.5 1 0.02 205 722 2580 13 11 0.39 4 14 12 0.74 46 90 13 11 9 0.29 5 11 8 0.24 20 49 2.7 10 10 0.28 6 6.8 4 0.08 16 27 1.1 9.7 11 0.29 7 6.2 4 0.06 14 6 0.25 9.5 12 0.30 8 5.8 3 0.05 12 2 0.07 9.2 11 0.28 9 5.6 2 0.04 12 3 0.09 9.0 10 0.25 10 5.7 2 0.03 13 3 0.10 9.0 10 0.23 11 51 539 389 11 3 0.09 9.0 9 0.22 12 121 425 300 10 3 0.08 9.3 9 0.23 13 48 78 18 9.9 3 0.08 11 10 0.28 14 31 42 9.1 9.6 3 0.08 8.4 10 0.23 15 25 23 2.6 9.7 3 0.07 42 78 25 16 12 6 0.20 9.5 2 0.06 16 17 0.97 17 9.9 6 0.17 14 10 0.57 36 76 22 18 16 7 0.28 17 14 0.76 25 69 4.7 19 14 7 0.26 13 9 0.29 13 11 0.40 20 8.9 7 0.16 11 4 0.11 66 144 78 21 8.1 6 0.14 9.4 3 0.08 134 353 349 22 8.0 6 0.14 9.7 3 0.08 148 457 575 23 88 268 193 26 29 2.5 51 80 14 24 33 38 4.5 12 12 0.40 26 9 0.59 25 15 13 0.50 10 9 0.25 17 3 0.15 26 11 10 0.32 15 14 0.84 16 5 0.20 27 10 8 0.21 17 17 0.95 13 6 0.20 28 9.6 6 0.14 11 6 0.18 10 6 0.16 29 17 3 0.13 11 7 0.21 9.1 5 0.13 30 19 1 0.07 11 9 0.27 8.4 5 0.11 31 12 1 0.04 11 11 0.30 --- --- --- TOTAL 646.4 --- 920.28 615.8 --- 2605.67 783.6 --- 1076.18 YEAR 7050.8 8962.73 e Estimated 129 RIO GRANDE DE ARECIBO BASIN 50026400 RIO YUNES AT HWY 140 NEAR FLORIDA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) OCTOBER NOVEMBER DECEMBER 1 9.8 6 0.17 107 341 426 23 4 0.25 2 9.6 6 0.17 53 88 17 23 4 0.25 3 26 30 5.4 20 34 1.9 30 19 2.4 4 17 13 0.67 16 17 0.78 30 26 2.1 5 15 13 0.55 15 9 0.37 25 20 1.4 6 11 7 0.20 14 10 0.39 23 18 1.1 7 10 5 0.13 32 34 5.1 22 15 0.86 8 22 21 2.8 1660 4940 30700 20 12 0.65 9 28 25 2.7 325 1090 1020 19 9 0.46 10 192 551 1310 155 489 212 19 6 0.30 11 77 171 54 88 249 61 19 3 0.17 12 33 15 1.4 68 90 16 25 14 1.2 13 21 15 0.84 56 60 9.2 26 20 1.4 14 19 15 0.78 51 33 4.5 30 26 2.2 15 16 14 0.61 45 9 1.1 25 14 0.96 16 14 7 0.26 40 5 0.53 70 170 91 17 14 5 0.20 37 5 0.49 56 72 11 18 14 6 0.21 35 5 0.45 43 30 3.8 19 12 6 0.20 33 5 0.43 33 5 0.43 20 12 6 0.18 32 5 0.40 28 4 0.33 21 12 5 0.17 30 5 0.38 33 21 2.7 22 11 5 0.16 29 5 0.36 35 35 3.4 23 11 6 0.17 28 5 0.34 128 300 184 24 11 9 0.26 31 5 0.38 80 128 32 25 11 12 0.34 28 4 0.34 45 73 8.8 26 11 12 0.35 26 4 0.31 36 66 6.4 27 11 12 0.35 27 4 0.31 32 60 5.2 28 63 134 83 28 4 0.33 30 54 4.3 29 28 30 2.9 28 4 0.32 28 47 3.6 30 16 13 0.58 25 4 0.28 26 41 2.9 31 12 8 0.28 --- --- --- 25 34 2.3 TOTAL 769.4 --- 1470.03 3162 --- 32480.99 1087 --- 377.86 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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 FEBRUARY MARCH 1 24 28 1.8 15 4 0.14 16 4 0.17 2 23 22 1.3 14 3 0.13 16 4 0.16 3 22 15 0.92 14 3 0.13 16 4 0.15 4 22 9 0.52 15 3 0.14 16 3 0.15 5 37 35 4.8 14 3 0.12 15 3 0.13 6 44 42 5.1 14 3 0.13 14 3 0.12 7 38 28 3.1 15 3 0.14 14 3 0.11 8 30 12 1.0 13 3 0.12 16 2 0.09 9 27 8 0.59 13 3 0.11 14 2 0.08 10 24 6 0.36 12 3 0.11 26 30 4.9 11 23 5 0.32 11 3 0.10 52 76 31 12 22 5 0.29 11 3 0.10 40 49 7.4 13 21 5 0.26 11 3 0.09 19 14 0.74 14 20 4 0.24 11 3 0.09 16 9 0.40 15 20 4 0.22 10 3 0.09 14 7 0.27 16 21 4 0.22 10 3 0.09 14 5 0.17 17 20 4 0.22 10 3 0.08 17 4 0.17 18 20 4 0.21 9.9 3 0.08 13 3 0.11 19 19 4 0.20 40 44 5.9 14 3 0.10 20 19 4 0.19 22 17 1.1 12 2 0.07 21 18 4 0.19 16 7 0.31 11 3 0.09 22 18 4 0.19 16 5 0.21 11 4 0.11 23 18 4 0.18 18 5 0.23 10 5 0.13 24 22 4 0.22 18 5 0.22 9.7 4 0.10 25 17 4 0.17 17 4 0.21 9.0 3 0.08 26 16 4 0.16 20 4 0.24 8.9 3 0.07 27 16 4 0.16 18 4 0.21 8.9 3 0.07 28 17 4 0.17 17 4 0.18 16 13 1.3 29 17 4 0.16 --- --- --- 14 9 0.42 30 16 4 0.15 --- --- --- 11 8 0.28 31 16 4 0.15 --- --- --- 21 32 14 TOTAL 687 --- 23.76 424.9 --- 10.80 504.5 --- 63.14 130 RIO GRANDE DE ARECIBO BASIN 50026400 RIO YUNES AT HWY 140 NEAR FLORIDA, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) APRIL MAY JUNE 1 55 96 42 197 483 731 25 11 1.0 2 28 28 2.6 166 387 338 25 9 0.59 3 13 16 0.59 101 172 48 28 17 1.5 4 11 11 0.32 74 104 21 28 6 0.48 5 85 326 260 63 74 13 32 18 1.7 6 78 166 61 60 69 11 25 6 0.45 7 55 69 12 51 49 6.7 21 3 0.19 8 101 168 57 46 38 4.8 20 4 0.22 9 60 73 13 44 9 1.1 19 5 0.26 10 36 43 4.2 40 7 0.74 19 6 0.31 11 29 29 2.3 38 8 0.87 18 7 0.34 12 23 27 1.7 36 10 1.0 18 8 0.38 13 19 26 1.3 34 12 1.1 19 8 0.43 14 18 26 1.2 33 12 1.1 18 9 0.44 15 20 25 1.3 53 65 29 16 10 0.43 16 26 15 1.1 36 13 1.2 16 8 0.35 17 24 14 1.0 31 10 0.86 18 6 0.30 18 92 267 258 30 11 0.92 20 5 0.25 19 52 62 9.9 28 12 0.94 17 3 0.15 20 88 173 80 26 14 0.95 16 4 0.17 21 101 215 76 25 15 0.97 16 5 0.21 22 43 108 13 23 16 0.98 15 5 0.23 23 254 852 2330 22 14 0.86 14 6 0.24 24 258 812 1570 21 12 0.69 15 7 0.28 25 193 519 640 20 11 0.59 14 8 0.30 26 134 314 271 19 15 0.77 14 9 0.33 27 156 371 278 20 19 1.0 16 9 0.40 28 107 209 65 19 22 1.1 14 10 0.39 29 267 844 2390 18 18 0.84 13 10 0.35 30 151 232 122 17 12 0.58 13 4 0.15 31 --- --- --- 19 6 0.31 --- --- --- TOTAL 2577 --- 8565.51 1410 --- 1221.97 562 --- 12.82 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) JULY AUGUST SEPTEMBER 1 12 7 0.23 54 110 56 22 28 1.7 2 12 10 0.32 34 52 7.6 77 199 142 3 12 10 0.33 28 24 1.9 62 98 21 4 12 11 0.34 171 646 1440 130 351 499 5 12 11 0.34 47 208 28 104 235 152 6 18 16 1.0 26 70 5.3 50 65 9.8 7 16 12 0.61 20 19 1.0 33 15 1.4 8 11 8 0.25 18 25 1.2 27 11 0.84 9 47 97 59 55 124 74 25 12 0.77 10 e27 e33 e2.7 31 47 4.4 22 12 0.72 11 e18 e10 e0.44 147 477 534 21 12 0.70 12 e30 e36 e3.3 52 209 31 19 12 0.65 13 e15 e16 e1.0 26 118 8.4 18 13 0.63 14 e14 e11 e0.40 28 39 2.8 26 31 3.3 15 e13 e10 e0.34 23 19 1.2 48 64 14 16 12 9 0.29 20 17 0.92 39 38 4.2 17 e13 e9 e0.34 19 17 0.84 25 19 1.3 18 e15 e9 e0.30 18 16 0.79 192 550 1430 19 e11 e9 e0.26 18 15 0.74 150 447 716 20 11 9 0.26 17 15 0.67 58 98 16 21 e11 e9 e0.25 16 14 0.60 36 19 2.0 22 e16 e9 e0.34 18 14 0.74 30 10 0.85 23 13 9 0.30 33 33 3.9 27 10 0.72 24 11 8 0.25 24 20 1.4 31 22 2.2 25 e10 e8 e0.23 21 17 0.94 30 13 1.1 26 e10 e8 e0.22 17 14 0.66 29 16 1.4 27 10 8 0.22 16 13 0.55 27 10 0.75 28 19 15 1.0 15 12 0.47 24 9 0.58 29 e15 e11 e0.49 21 18 1.6 23 8 0.50 30 e10 e8 e0.22 27 24 1.9 21 7 0.42 31 15 16 1.8 31 30 3.1 --- --- --- TOTAL 471 --- 77.37 1091 --- 2216.62 1426 --- 3026.53 YEAR 14171.8 49547.40 e Estimated 131 RIO GRANDE DE ARECIBO BASIN 50027000 RIO LIMON ABOVE LAGO DOS BOCAS, PR LOCATION.--Lat 18°19'32", long 66°37'24", Hydrologic Unit 21010002, on right bank off Highway 146, 2.2 mi (3.5 km) northwest from Escuela Segunda Unidad de Mameyes, 3.0 mi (4.8 km) southwest from Lago Dos Bocas Dam, 3.8 mi (6.0 km) northeast from Lago Caonillas Dam. DRAINAGE AREA.--33.2 mi2 (86.0 km2). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--December 1999 to current year. GAGE.--Water-stage recorder. Datum of gage is 311.6 ft (94.9 m), from topographic map. REMARKS.--Records fair. Gage-height and precipitation satellite telemetry at station. Discharge, cubic feet per second WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 42 269 62 54 40 34 229 421 74 49 140 49 2 39 117 61 52 37 34 127 360 74 49 99 121 3 61 57 97 49 36 33 59 238 77 48 76 136 4 56 51 97 48 38 32 46 194 78 48 195 389 5 50 46 75 80 35 31 247 174 80 47 90 236 6 41 44 65 113 36 30 217 166 73 58 63 118 7 38 107 61 97 41 30 138 149 68 59 55 86 8 60 3990 57 75 33 33 246 140 67 48 52 74 9 67 662 54 70 33 32 157 133 66 72 83 69 10 369 293 53 64 32 48 102 127 65 64 71 65 11 240 198 52 61 32 101 83 123 63 57 231 64 12 94 162 72 59 31 91 69 120 62 68 103 60 13 62 142 71 57 31 42 60 118 63 53 64 58 14 56 138 78 55 30 36 55 116 61 48 65 69 15 50 121 65 53 29 33 59 181 59 47 58 103 16 46 111 142 52 28 32 81 122 58 45 52 83 17 44 103 124 51 27 43 74 106 60 47 49 62 18 43 98 95 49 27 32 198 100 63 45 49 357 19 40 93 76 47 118 35 122 95 60 43 50 193 20 38 89 64 46 68 30 168 91 58 42 45 93 21 38 85 117 46 45 30 200 89 58 41 42 66 22 38 80 99 45 40 29 107 86 55 49 48 57 23 36 78 252 44 38 28 685 85 54 49 79 53 24 36 91 163 55 36 27 720 82 56 43 64 58 25 35 76 103 44 35 26 639 81 54 41 51 56 26 35 72 82 42 42 26 305 79 53 40 42 53 27 35 73 72 42 39 26 479 79 55 41 38 50 28 140 74 65 45 35 45 261 78 54 54 37 47 29 69 73 62 44 --- 46 876 75 52 51 47 45 30 48 66 59 42 --- 36 383 74 50 42 51 44 31 40 --- 56 41 --- 116 --- 72 --- 52 57 --- TOTAL 2086 7659 2651 1722 1092 1247 7192 4154 1870 1540 2246 3014 MEAN 67.3 255 85.5 55.5 39.0 40.2 240 134 62.3 49.7 72.5 100 MAX 369 3990 252 113 118 116 876 421 80 72 231 389 MIN 35 44 52 41 27 26 46 72 50 40 37 44 AC-FT 4140 15190 5260 3420 2170 2470 14270 8240 3710 3050 4450 5980 CFSM 2.03 7.69 2.58 1.67 1.17 1.21 7.22 4.04 1.88 1.50 2.18 3.03 IN. 2.34 8.58 2.97 1.93 1.22 1.40 8.06 4.65 2.10 1.73 2.52 3.38 STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 2000 - 2002, BY WATER YEAR (WY) MEAN 85.7 164 60.8 64.6 42.4 35.5 102 95.4 42.3 39.0 51.0 76.2 MAX 104 255 85.5 108 60.8 45.7 240 134 62.3 49.7 72.5 100 (WY) 2001 2002 2002 2000 2000 2000 2002 2002 2002 2002 2002 2002 MIN 67.3 72.8 36.1 30.1 26.9 20.5 29.7 54.7 27.4 31.0 31.7 57.3 (WY) 2002 2001 2001 2001 2001 2001 2001 2001 2001 2000 2000 2000 SUMMARY STATISTICS FOR 2001 CALENDAR YEAR FOR 2002 WATER YEAR WATER YEARS 2000 - 2002 ANNUAL TOTAL 22889 36473 ANNUAL MEAN 62.7 99.9 73.3 HIGHEST ANNUAL MEAN 99.9 2002 LOWEST ANNUAL MEAN 46.6 2001 HIGHEST DAILY MEAN 3990 Nov 8 3990 Nov 8 3990 Nov 8 2001 LOWEST DAILY MEAN 14 Apr 18 26 Mar 25 14 Apr 18 2001 ANNUAL SEVEN-DAY MINIMUM 16 Apr 15 27 Mar 21 16 Apr 15 2001 MAXIMUM PEAK FLOW 11500 Nov 8 11500 Nov 8 2001 MAXIMUM PEAK STAGE 15.63 Nov 8 15.63 Nov 8 2001 INSTANTANEOUS LOW FLOW 25 Mar 25 13 Apr 18 2001 ANNUAL RUNOFF (AC-FT) 45400 72340 53090 ANNUAL RUNOFF (CFSM) 1.89 3.01 2.21 ANNUAL RUNOFF (INCHES) 25.65 40.87 29.99 10 PERCENT EXCEEDS 106 164 123 50 PERCENT EXCEEDS 30 59 46 90 PERCENT EXCEEDS 19 35 22 132 RIO GRANDE DE ARECIBO BASIN 50027000 RIO LIMON ABOVE LAGO DOS BOCAS, PR--Continued O N D 2001 J F M A M J J A S 2002 10 20 50 100 100 200 500 1000 1000 2000 5000 10,000 DISCHARGE, IN CUBIC FEET PER SECOND 133 RIO GRANDE DE ARECIBO BASIN 50027000 RIO LIMON ABOVE LAGO DOS BOCAS, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--December 1999 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED SEDIMENT DISCHARGE: December 1999 to current year. INSTRUMENTATION.--USDH-48 and automatic sediment samplers since 2000. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATION: Maximum daily mean, 2,420 mg/L November 8, 2001; Minimum daily mean, 1 mg/L several days during water year 2001. SEDIMENT LOADS: Maximum daily mean, 42,800 tons (38,830 tonnes) November 8, 2001; Minimum daily mean, 0.08 ton (0.07 tonne) February 6, 7, 2001. EXTREMES FOR CURRENT YEAR 2002.-- SEDIMENT CONCENTRATION: Maximum daily mean, 2,420 mg/L November 8, 2001; Minimum daily mean, 2 mg/L several days. SEDIMENT LOADS: Maximum daily mean, 42,800 tons (38,830 tonnes) November 8, 2001; Minimum daily mean, 0.20 ton (0.18 tonne) October 27, 2001. WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 TURBID- FECAL FECAL SPECIF. PH, ITY, DIS- COD, COLI- STREP- HARD- INSTAN- CONDUC- WATER, WAT UNF SOLVED HIGH FORM, TOCOCCI NESS, TANEOUS TANCE, UNFLTRD TEMPER- LAB, DIS- OXYGEN, LEVEL, M-FC KF WATER, CALCIUM DIS- WAT UNF FIELD, ATURE, HACH SOLVED PERCENT WATER, 0.7U MF MF, UNFLTRD WATER, DATE TIME CHARGE, US/CM STD WATER, 2100AN OXYGEN, OF SAT- UNFLTRD COL/ COL/ MG/L AS FLTRD, CFS 25 DEGC UNITS DEG C NTU MG/L URATION MG/L 100 ML 100 ML CACO3 MG/L (00061) (00095) (00400) (00010) (99872) (00300) (00301) (00340) (31625) (31673) (00900) (00915) DEC 12... 1325 53 201 7.3 24.2 2.4 8.5 102 <10 E45 E150 73 19.6 MAR 12... 1425 54 154 7.1 25.0 120 7.9 98 10 E8820 9700 -- -- SEP 05... 1155 134 129 6.5 25.5 50 8.0 99 <10 2900 3300 49 12.9 ANC, RESIDUE RESIDUE WAT UNF WATER, TOTAL MAGNES- POTAS- FIXED CHLOR- FLUOR- FLTRD, AT 105 IUM, SODIUM, SODIUM SIUM, END PT, SULFIDE SULFATE IDE, IDE, SILICA, SUM OF RESIDUE DEG. C, WATER, WATER, ADSORP- WATER, FIELD, WATER WATER, WATER, WATER, WATER, CONSTI- WATER, SUS- DATE FLTRD, FLTRD, TION FLTRD, MG/L AS UNFLTRD FLTRD, FLTRD, FLTRD, FLTRD, TUENTS FLTRD, PENDED, MG/L MG/L RATIO MG/L CACO3 MG/L MG/L MG/L MG/L MG/L MG/L TONS/D MG/L (00925) (00930) (00931) (00935) (00410) (00745) (00945) (00940) (00950) (00955) (70301) (70302) (00530) DEC 12... 5.80 8.66 .4 1.97 71 <1.0 3.8 9.66 E.1 27.6 120 17.0 <10 MAR 12... -- -- -- -- 49 -- -- -- -- -- -- -- 60 SEP 05... 4.02 6.60 .4 2.33 42 .2 5.6 7.39 E.08 21.6 86 31.0 22 NITRITE AMMONIA CHROM- + + BARIUM, BORON, IUM, COPPER, IRON, LEAD, NITRITE NITRATE AMMONIA ORG-N, PHOS- WATER, WATER, WATER, WATER, WATER, WATER, WATER, WATER WATER, WATER, PHORUS, ARSENIC UNFLTRD UNFLTRD CADMIUM UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD WATER, WATER RECOV- RECOV- WATER, RECOV- RECOV- RECOV- RECOV- DATE MG/L MG/L MG/L MG/L UNFLTRD UNFLTRD ERABLE, ERABLE, UNFLTRD ERABLE, ERABLE, ERABLE, ERABLE, AS N AS N AS N AS N MG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L (00615) (00630) (00610) (00625) (00665) (01002) (01007) (01022) (01027) (01034) (01042) (01045) (01051) DEC 12... <.01 1.20 <.01 <.20 E.03 4 40.1 E10 <.1 <.8 <10 50 <1 MAR 12... .02 1.60 .03 .60 .12 -- -- -- -- -- -- -- -- SEP 05... .01 1.20 .01 .30 .06 <2 43.6 E10 <.1 1.0 M 810 M MANGAN- PHEN- ESE, MERCURY SILVER, ZINC, OLIC WATER, WATER, SELEN- WATER, WATER, COM- UNFLTRD UNFLTRD IUM, UNFLTRD UNFLTRD CYANIDE POUNDS, MBAS, RECOV- RECOV- WATER, RECOV- RECOV- WATER WATER, WATER, DATE ERABLE, ERABLE, UNFLTRD ERABLE, ERABLE, UNFLTRD UNFLTRD UNFLTRD UG/L UG/L UG/L UG/L UG/L MG/L UG/L MG/L (01055) (71900) (01147) (01077) (01092) (00720) (32730) (38260) DEC 12... 4.0 <.01 5 <.3 <20 <.01 <17 <.05 MAR 12... -- -- -- -- -- -- -- -- SEP 05... 37.2 <.01 <2 <.3 <20 <.01 <16 <.05 < -- Less than E -- Estimated value M -- Presence verified, not quantified 134 RIO GRANDE DE ARECIBO BASIN 50027000 RIO LIMON ABOVE LAGO DOS BOCAS, PR--Continued WATER-QUALITY RECORDS SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) OCTOBER NOVEMBER DECEMBER 1 42 3 0.34 269 601 1450 62 2 0.34 2 39 3 0.32 117 76 39 61 2 0.33 3 61 12 3.1 57 9 1.5 97 17 8.8 4 56 15 2.4 51 4 0.61 97 12 4.1 5 50 13 1.9 46 4 0.46 75 2 0.49 6 41 10 1.1 44 3 0.37 65 2 0.35 7 38 9 0.97 107 49 35 61 2 0.33 8 60 17 3.9 3990 2420 42800 57 2 0.31 9 67 18 3.5 662 382 786 54 2 0.29 10 369 974 3530 293 60 53 53 2 0.29 11 240 348 599 198 22 12 52 4 0.53 12 94 33 9.5 162 10 4.5 72 8 1.6 13 62 9 1.6 142 8 3.0 71 9 1.8 14 56 9 1.3 138 9 3.2 78 11 2.2 15 50 8 1.0 121 7 2.2 65 11 1.9 16 46 6 0.69 111 5 1.4 142 541 499 17 44 5 0.61 103 4 1.2 124 377 127 18 43 4 0.51 98 4 1.0 95 183 50 19 40 4 0.40 93 3 0.85 76 47 10 20 38 3 0.32 89 3 0.71 64 25 4.3 21 38 3 0.34 85 3 0.58 117 284 160 22 38 4 0.37 80 2 0.46 99 82 22 23 36 4 0.38 78 2 0.50 252 260 343 24 36 4 0.35 91 3 0.70 163 27 13 25 35 3 0.29 76 4 0.72 103 11 3.0 26 35 3 0.24 72 4 0.81 82 9 2.0 27 35 2 0.20 73 5 0.94 72 8 1.6 28 140 320 368 74 4 0.83 65 7 1.3 29 69 18 3.8 73 3 0.59 62 6 1.1 30 48 12 1.7 66 2 0.37 59 6 0.90 31 40 6 0.67 --- --- --- 56 5 0.78 TOTAL 2086 --- 4538.80 7659 --- 45202.50 2651 --- 1262.64 135 RIO GRANDE DE ARECIBO BASIN 50027000 RIO LIMON ABOVE LAGO DOS BOCAS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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 FEBRUARY MARCH 1 54 6 0.80 40 6 0.68 34 6 0.51 2 52 6 0.83 37 7 0.68 34 5 0.47 3 49 6 0.86 36 7 0.73 33 5 0.41 4 48 7 0.89 38 8 0.82 32 4 0.35 5 80 20 5.5 35 8 0.76 31 4 0.35 6 113 30 9.2 36 8 0.77 30 4 0.36 7 97 26 6.9 41 8 0.88 30 5 0.38 8 75 18 3.6 33 8 0.69 33 5 0.45 9 70 12 2.3 33 7 0.62 32 5 0.46 10 64 11 1.8 32 7 0.58 48 9 1.8 11 61 9 1.5 32 6 0.53 101 37 26 12 59 8 1.2 31 6 0.50 91 22 7.4 13 57 6 0.94 31 6 0.49 42 8 0.91 14 55 5 0.68 30 6 0.48 36 7 0.65 15 53 3 0.40 29 6 0.47 33 5 0.48 16 52 2 0.32 28 6 0.46 32 5 0.41 17 51 3 0.36 27 6 0.44 43 4 0.51 18 49 3 0.39 27 6 0.43 32 4 0.36 19 47 3 0.42 118 116 56 35 4 0.42 20 46 4 0.46 68 20 3.7 30 5 0.40 21 46 4 0.50 45 11 1.4 30 5 0.43 22 45 4 0.52 40 6 0.61 29 6 0.46 23 44 4 0.53 38 4 0.38 28 6 0.44 24 55 5 0.70 36 3 0.33 27 6 0.41 25 44 5 0.59 35 3 0.30 26 5 0.38 26 42 5 0.54 42 4 0.49 26 5 0.36 27 42 4 0.50 39 6 0.62 26 5 0.36 28 45 4 0.50 35 7 0.66 45 11 2.5 29 44 5 0.63 --- --- --- 46 13 1.8 30 42 7 0.79 --- --- --- 36 10 0.98 31 41 8 0.85 --- --- --- 116 276 696 TOTAL 1722 --- 46.00 1092 --- 75.50 1247 --- 747.20 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) APRIL MAY JUNE 1 229 526 645 421 536 1350 74 14 2.7 2 127 167 103 360 375 673 74 14 2.8 3 59 27 4.3 238 73 47 77 15 3.1 4 46 23 2.8 194 59 31 78 16 3.3 5 247 509 1290 174 46 21 80 13 2.9 6 217 246 234 166 32 15 73 10 2.0 7 138 41 16 149 19 7.6 68 7 1.3 8 246 74 54 140 8 3.2 67 6 1.0 9 157 42 18 133 13 4.6 66 5 0.91 10 102 27 7.4 127 12 4.2 65 5 0.81 11 83 18 4.0 123 9 2.9 63 4 0.71 12 69 10 1.9 120 8 2.6 62 4 0.74 13 60 8 1.4 118 8 2.5 63 5 0.85 14 55 9 1.3 116 8 2.5 61 6 0.91 15 59 9 1.5 181 536 535 59 6 0.96 16 81 15 4.7 122 29 9.7 58 6 0.99 17 74 20 4.3 106 16 4.7 60 6 1.0 18 198 279 668 100 11 2.9 63 7 1.1 19 122 36 12 95 9 2.2 60 7 1.1 20 168 175 165 91 8 2.0 58 8 1.2 21 200 188 168 89 7 1.8 58 9 1.4 22 107 30 8.6 86 7 1.6 55 10 1.5 23 685 1000 6570 85 6 1.4 54 11 1.6 24 720 927 4850 82 6 1.3 56 12 1.9 25 639 718 3710 81 5 1.1 54 14 2.0 26 305 194 254 79 6 1.3 53 12 1.7 27 479 798 2240 79 8 1.7 55 10 1.4 28 261 94 74 78 9 1.8 54 7 1.1 29 876 984 9140 75 9 1.9 52 6 0.87 30 383 292 369 74 10 2.0 50 9 1.2 31 --- --- --- 72 11 2.2 --- --- --- TOTAL 7192 --- 30622.2 4154 --- 2741.7 1870 --- 45.05 136 RIO GRANDE DE ARECIBO BASIN 50027000 RIO LIMON ABOVE LAGO DOS BOCAS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) JULY AUGUST SEPTEMBER 1 49 12 1.6 140 170 226 49 23 3.1 2 49 15 1.9 99 31 11 121 153 234 3 48 17 2.2 76 41 8.5 136 135 113 4 48 14 1.8 195 256 598 389 324 1730 5 47 9 1.1 90 30 8.0 236 259 400 6 58 9 1.9 63 18 3.1 118 50 17 7 59 16 2.6 55 15 2.2 86 11 2.5 8 48 13 1.7 52 14 2.0 74 6 1.3 9 72 20 5.9 83 23 8.2 69 7 1.3 10 64 17 3.1 71 20 3.9 65 7 1.3 11 57 15 2.7 231 328 698 64 8 1.4 12 68 18 3.4 103 28 8.8 60 12 2.0 13 53 14 2.0 64 9 1.6 58 18 2.8 14 48 12 1.5 65 4 0.73 69 25 4.9 15 47 10 1.2 58 3 0.51 103 28 9.2 16 45 9 1.1 52 2 0.32 83 16 3.8 17 47 10 1.2 49 3 0.35 62 9 1.6 18 45 10 1.2 49 3 0.45 357 554 2430 19 43 10 1.2 50 4 0.57 193 244 402 20 42 11 1.2 45 5 0.61 93 21 5.7 21 41 11 1.2 42 6 0.65 66 16 2.8 22 49 11 1.5 48 9 1.4 57 18 2.8 23 49 12 1.5 79 22 5.4 53 20 2.9 24 43 12 1.4 64 18 3.4 58 22 3.5 25 41 12 1.4 51 13 1.9 56 19 2.9 26 40 13 1.4 42 12 1.3 53 14 2.0 27 41 13 1.4 38 12 1.2 50 9 1.3 28 54 13 2.0 37 11 1.1 47 5 0.63 29 51 14 1.9 47 13 1.8 45 5 0.65 30 42 14 1.6 51 14 1.9 44 6 0.71 31 52 17 2.8 57 36 5.7 --- --- --- TOTAL 1540 --- 58.6 2246 --- 1608.59 3014 --- 5387.09 YEAR 36473 92335.87 WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT Sus- Suspnd. pended Sus- sedi- Instan- sedi- pended ment, taneous ment sedi- sieve dis- concen- ment diametr Date Time charge, tration load, percent cfs mg/L tons/d <.062mm (00061) (80154) (80155) (70331) NOV 01... 1700 1380 4940 18400 99 DEC 16... 1915 463 1420 1770 99 APR 01... 0140 475 1110 1420 99 137 RIO GRANDE DE ARECIBO BASIN 50027000 RIO LIMON ABOVE LAGO DOS BOCAS, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 PARTICLE SIZE DISTRIBUTION OF SUSPENDED SEDIMENT Sus- Suspnd. Suspnd. Suspnd. Suspnd. Suspnd. Suspnd. Suspnd. Suspnd. Suspnd. pended Sus- sedi- sedi- sedi- sedi- sedi- sedi- sedi- sedi- sedi- Instan- sedi- pended ment, ment, ment, ment, ment, ment, ment, ment, ment, taneous ment sedi- falldia falldia falldia falldia falldia sieve sieve sieve sieve dis- concen- ment nat wat nat wat nat wat nat wat nat wat diametr diametr diametr diametr Date Time charge, tration load, percent percent percent percent percent percent percent percent percent cfs mg/L tons/d <.002mm <.004mm <.008mm <.016mm <.031mm <.062mm <.125mm <.25mm <.5 mm (00061) (80154) (80155) (70326) (70327) (70328) (70329) (70330) (70331) (70332) (70333) (70334) NOV 08... 0705 9110 4590 113000 45 54 67 79 89 94 98 99 99 DEC 23... 1403 728 1380 2710 51 61 76 86 96 97 99 99 100 Suspnd. sedi- ment, sieve diametr Date percent <1 mm (70335) NOV 08... 100 DEC 23... 100 138 RIO GRANDE DE ARECIBO BASIN 50027100 LAGO DOS BOCAS AT DAMSITE NEAR UTUADO, PR LOCATION.--Lat 18°20'16", long 66°40'05", Hydrologic Unit 21010001, on upstream side of road 146 over damsite, close to the center of dam, 10 mi (16 km) southeast of the city of Arecibo, 4.1 mi (6.6 km) north of Lago Caonillas Dam, 5.3 mi (8.5 km) northeast of Utuado Plaza, and 3.8 mi (6.1 km) southeast of Escuela Antonio Sánchez de Padilla. DRAINAGE AREA.--169.45 mi2 (438.87 km2). ELEVATION RECORDS PERIOD OF RECORD.--March 1999 to current year. GAGE.--Water-stage recorder. Datum of gage is mean sea level. REMARKS.--Lago Dos Bocas was completed in 1942. The dam is a concrete gravity structure with a total length of 1,317 ft (401.4 m), a maximum height of 188 ft (57.3 m), and a maximum base width of 158 ft (48.2 m). No-overflow sections on each abutment have a total lenght of 957 ft (292 m). The dam and the powerplant comprise the Dos Bocas Hydroelectric Project, and provides 32,000 acre-feet (39.456 km3). A three-unit powerplant is located on the right bank of the slitting basin. The dam is owned by Puerto Rico Electric Power Authority. The capacity of Lago Dos Bocas was computed to be 714.40 million ft3 (20.23 million m3) for June 1997. Gage-height and precipitation satellite telemetry at station. EXTREMES OBSERVED FOR PERIOD OF RECORD.--Maximum elevation, 298.81 ft (91.08 m), November 8, 2001; minimum elevation, 283.88 ft (86.526 m), August 21, 2000. EXTREMES OBSERVED FOR CURRENT YEAR.--Maximum elevation, 298.81 ft (91.08 m), November 8, 2001; minimum elevation, 286.40 ft (87.29 m), March 26. 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 216 0 275 9,283 236 1,403 288 13,684 256 4,491 295 16,400 Elevation above NGVD 1929, feet WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 DAILY OBSERVATION AT 2400 HOURS DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 289.52 289.17 291.39 290.22 290.44 290.69 290.58 294.17 290.15 291.33 290.56 291.48 2 289.31 291.81 292.00 289.99 290.17 290.78 292.03 293.51 290.54 291.45 290.88 293.07 3 290.17 292.84 292.60 289.58 290.58 290.32 291.66 291.57 291.45 290.74 290.50 292.63 4 290.33 293.05 293.48 289.19 290.06 290.63 291.35 291.12 292.37 290.95 291.98 292.45 5 291.08 293.18 292.71 290.05 290.31 291.03 293.92 291.41 291.66 290.97 291.17 292.37 6 291.43 292.50 291.72 290.38 290.71 290.27 292.48 291.24 289.64 291.41 291.22 292.23 7 290.99 292.81 292.72 289.36 291.29 289.77 291.06 291.62 289.91 291.72 290.92 290.84 8 289.46 296.76 292.52 289.18 291.80 289.35 292.91 292.15 290.07 291.85 290.99 291.10 9 288.22 295.02 291.91 289.13 292.29 288.97 293.14 292.02 290.18 291.73 291.94 291.05 10 291.90 293.76 290.86 289.26 291.08 288.51 291.46 292.24 290.37 290.76 291.83 290.71 11 294.18 293.38 290.82 289.74 291.62 288.97 291.23 291.76 290.09 290.31 293.64 290.75 12 291.69 293.96 291.71 289.53 291.28 289.28 290.43 291.62 290.34 291.28 291.07 291.04 13 291.33 293.65 291.36 289.37 290.80 289.10 290.60 292.11 289.54 291.62 289.28 291.47 14 291.75 293.86 291.85 287.93 290.60 288.84 290.88 290.83 289.61 291.58 290.84 288.87 15 290.20 292.68 291.75 289.10 290.94 289.15 289.82 290.62 289.61 290.99 290.49 288.41 16 290.69 292.25 292.52 289.38 289.82 288.28 290.16 292.44 289.23 291.08 291.29 289.98 17 290.78 293.07 292.78 289.85 290.06 288.83 289.77 291.33 287.96 292.07 291.30 289.52 18 290.63 293.01 291.45 290.11 290.58 288.41 290.54 291.96 A 289.31 291.69 292.36 19 291.19 A 289.64 290.15 291.87 288.84 291.49 292.54 287.80 289.61 291.41 292.73 20 290.91 292.00 290.56 290.62 291.82 289.26 293.51 292.85 288.18 289.81 291.74 290.77 21 291.07 291.29 290.65 290.98 291.59 288.88 291.48 291.38 288.97 289.88 290.82 291.30 22 291.00 290.64 290.46 291.44 291.31 288.34 292.11 290.18 289.21 289.82 292.02 291.32 23 290.97 289.97 291.45 291.29 290.99 287.65 294.84 289.75 289.32 290.10 291.53 A 24 289.84 289.98 291.24 290.62 291.03 287.18 295.06 290.06 289.77 290.37 292.95 287.70 25 289.58 290.17 291.76 289.86 290.44 286.92 294.99 289.21 290.13 290.06 291.82 291.38 26 290.21 289.91 290.89 289.66 290.15 286.56 293.54 289.38 290.58 289.97 291.75 291.00 27 291.55 287.57 289.93 289.29 289.76 287.08 295.51 289.19 290.95 290.43 290.86 290.97 28 292.92 289.37 289.87 289.39 290.25 287.83 294.37 289.57 290.88 290.42 290.15 291.58 29 292.50 290.37 289.76 289.03 --- 288.46 296.12 289.93 291.18 289.48 290.08 290.50 30 290.84 291.32 289.68 289.20 --- 288.84 294.52 289.45 291.16 289.32 290.43 289.57 31 289.48 --- 289.38 289.84 --- 289.17 --- 289.19 --- 289.50 290.58 --- MAX 294.18 --- 293.48 291.44 292.29 291.03 296.12 294.17 --- 292.07 293.64 --- MIN 288.22 --- 289.38 287.93 289.76 286.56 289.77 289.19 --- 289.31 289.28 --- A No gage-height record 139 RIO GRANDE DE ARECIBO BASIN 50027100 LAGO DOS BOCAS AT DAMSITE NEAR UTUADO, PR--Continued O N D 2001 J F M A M J J A S 2002 286 288 290 292 294 296 298 ELEVATION, IN FEET Gap indicates missing record 140 RIO GRANDE DE ARECIBO BASIN 50027250 RIO GRANDE DE ARECIBO BELOW LAGO DOS BOCAS NEAR FLORIDA, PR LOCATION.--Lat 18°20'50", long 66°40'02", Hydrologic Unit 21010001, at pedestrian bridge, 0.7 mi (1.1 km) downstream from Lago Dos Bocas and 6.6 mi, (6.6 km), west of Florida Plaza. DRAINAGE AREA.--170 mi2 (440 km2) does not include 6.0 mi2 (15.6 km2) above Lago Garzas. WATER-DISCHARGE RECORDS PERIOD OF RECORD.--May 2000 to September 2002. (discontinued) GAGE.--Water-stage recorder. Elevation of gage is 101.6 ft (40 m), from topographic map. REMARKS.--Records poor. Regulation at all stages by Puerto Rico Electric Power Authority reservoir upstream from gage. Gage-height and precipitation satellite telemetry at station. Discharge, cubic feet per second WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 875 775 488 68 33 60 356 2110 40 301 188 259 2 506 36 478 404 298 161 34 2000 193 297 332 709 3 89 318 708 448 113 319 436 2020 45 543 389 1620 4 328 398 654 453 381 93 389 1570 196 301 382 1360 5 36 325 996 157 134 45 403 1310 670 301 618 1020 6 252 599 990 356 130 404 1620 1400 993 269 288 537 7 425 574 447 705 45 308 1280 1230 259 254 354 817 8 1160 8360 730 415 34 303 945 1080 275 314 220 246 9 1030 3450 862 348 34 301 613 1070 283 586 33 449 10 293 1680 1070 300 739 412 994 1180 259 677 406 558 11 160 1150 868 208 39 304 649 989 582 601 297 530 12 1230 585 559 456 321 295 799 918 308 511 1310 305 13 487 e500 539 355 356 287 558 744 890 278 1060 307 14 221 e1000 231 750 277 289 284 894 536 386 122 1230 15 846 999 364 35 102 106 718 1350 289 574 756 745 16 273 641 387 508 577 460 640 791 387 311 366 209 17 357 191 870 507 130 46 805 1250 788 36 306 565 18 325 419 1150 295 41 304 486 284 445 1180 302 384 19 137 510 1210 488 38 65 637 288 452 346 610 988 20 342 676 364 339 304 36 624 468 331 239 302 1160 21 206 808 724 363 305 305 1950 914 164 273 852 362 22 406 767 707 403 299 347 615 808 291 401 202 351 23 539 783 680 376 300 377 1320 772 304 272 789 1050 24 796 645 893 503 193 312 2400 421 281 221 358 726 25 357 439 361 513 387 285 2800 734 255 272 875 27 26 82 663 716 331 300 334 2200 245 258 203 376 272 27 61 1220 726 375 316 51 2130 504 300 27 724 594 28 364 42 379 291 43 33 3410 278 418 301 622 186 29 706 337 379 366 --- 60 3030 564 265 575 531 646 30 989 289 345 193 --- 182 3350 603 367 248 236 548 31 559 --- 434 34 --- 314 --- 408 --- 243 399 --- TOTAL 14437 29179 20309 11343 6269 7198 36475 29197 11124 11341 14605 18760 MEAN 466 973 655 366 224 232 1216 942 371 366 471 625 MAX 1230 8360 1210 750 739 460 3410 2110 993 1180 1310 1620 MIN 36 36 231 34 33 33 34 245 40 27 33 27 AC-FT 28640 57880 40280 22500 12430 14280 72350 57910 22060 22490 28970 37210 CFSM 2.74 5.72 3.85 2.15 1.32 1.37 7.15 5.54 2.18 2.15 2.77 3.68 IN. 3.16 6.39 4.44 2.48 1.37 1.58 7.98 6.39 2.43 2.48 3.20 4.11 STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 2000 - 2002, BY WATER YEAR (WY) MEAN 813 768 490 303 206 221 697 784 376 338 488 753 MAX 1161 973 655 366 224 232 1216 942 393 429 503 996 (WY) 2001 2002 2002 2002 2002 2002 2002 2002 2001 2001 2001 2000 MIN 466 563 326 240 188 209 177 626 363 220 471 625 (WY) 2002 2001 2001 2001 2001 2001 2001 2001 2000 2000 2002 2002 SUMMARY STATISTICS FOR 2001 CALENDAR YEAR FOR 2002 WATER YEAR WATER YEARS 2000 - 2002 ANNUAL TOTAL 167684 210237 ANNUAL MEAN 459 576 516 HIGHEST ANNUAL MEAN 576 2002 LOWEST ANNUAL MEAN 457 2001 HIGHEST DAILY MEAN 8360 Nov 8 8360 Nov 8 8360 Nov 8 2001 LOWEST DAILY MEAN 26 Mar 31 27 Jul 27 21 Jul 3 2000 ANNUAL SEVEN-DAY MINIMUM 88 Apr 4 124 Feb 3 68 Jul 2 2000 MAXIMUM PEAK FLOW 16200 Nov 8 16200 Nov 8 2001 MAXIMUM PEAK STAGE 18.85 Nov 8 18.85 Nov 8 2001 ANNUAL RUNOFF (AC-FT) 332600 417000 374100 ANNUAL RUNOFF (CFSM) 2.70 3.39 3.04 ANNUAL RUNOFF (INCHES) 36.69 46.00 41.27 10 PERCENT EXCEEDS 916 1110 1050 50 PERCENT EXCEEDS 360 389 374 90 PERCENT EXCEEDS 32 118 39 e Estimated 141 RIO GRANDE DE ARECIBO BASIN 50027250 RIO GRANDE DE ARECIBO BELOW LAGO DOS BOCAS NEAR FLORIDA, PR--Continued O N D 2001 J F M A M J J A S 2002 10 20 50 100 100 200 500 1000 1000 2000 5000 10,000 DISCHARGE, IN CUBIC FEET PER SECOND 142 RIO GRANDE DE ARECIBO BASIN 50027250 RIO GRANDE DE ARECIBO BELOW LAGO DOS BOCAS NEAR FLORIDA, PR--Continued WATER-QUALITY RECORDS LOCATION.--Lat 18°20'50", long 66°40'02", at pedestrian bridge, 0.7 mi (1.1 km) downstream from Lago Dos Bocas and 6.6 mi (10.6 km) west of Florida Plaza. DRAINAGE AREA.--169 mi2 (436 km2). This does not include 6.0 mi2 (15.5 km2) above Lago Garzas. PERIOD OF RECORD.--Water years 1970-71, 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 TURBID- FECAL FECAL SPECIF. PH, ITY, DIS- COD, COLI- STREP- HARD- INSTAN- CONDUC- WATER, WAT UNF SOLVED HIGH FORM, TOCOCCI NESS, TANEOUS TANCE, UNFLTRD TEMPER- LAB, DIS- OXYGEN, LEVEL, M-FC KF WATER, CALCIUM DIS- WAT UNF FIELD, ATURE, HACH SOLVED PERCENT WATER, 0.7U MF MF, UNFLTRD WATER, DATE TIME CHARGE, US/CM STD WATER, 2100AN OXYGEN, OF SAT- UNFLTRD COL/ COL/ MG/L AS FLTRD, CFS 25 DEGC UNITS DEG C NTU MG/L URATION MG/L 100 ML 100 ML CACO3 MG/L (00061) (00095) (00400) (00010) (99872) (00300) (00301) (00340) (31625) (31673) (00900) (00915) DEC 12... 1000 -- 206 6.8 24.6 17 6.8 82 <10 E60 E90 73 19.9 MAR 11... 1310 29 229 7.3 26.0 2.6 6.5 80 <10 <10 E10 -- -- SEP 06... 0900 -- 174 6.8 26.1 130 5.3 66 <10 450 430 67 18.2 ANC, RESIDUE RESIDUE WAT UNF WATER, TOTAL MAGNES- POTAS- FIXED CHLOR- FLUOR- FLTRD, AT 105 NITRITE IUM, SODIUM, SODIUM SIUM, END PT, SULFIDE SULFATE IDE, IDE, SILICA, SUM OF DEG. C, WATER, WATER, WATER, ADSORP- WATER, FIELD, WATER WATER, WATER, WATER, WATER, CONSTI- SUS- UNFLTRD DATE FLTRD, FLTRD, TION FLTRD, MG/L AS UNFLTRD FLTRD, FLTRD, FLTRD, FLTRD, TUENTS PENDED, MG/L MG/L MG/L RATIO MG/L CACO3 MG/L MG/L MG/L MG/L MG/L MG/L MG/L AS N (00925) (00930) (00931) (00935) (00410) (00745) (00945) (00940) (00950) (00955) (70301) (00530) (00615) DEC 12... 5.54 8.47 .4 2.07 66 <1.0 9.9 8.93 E.1 21.6 116 10 <.01 MAR 11... -- -- -- -- 82 -- -- -- -- -- -- <10 .02 SEP 06... 5.30 8.40 .4 2.20 59 <.1 9.7 8.66 E.09 19.4 107 54 .02 NITRITE AMMONIA CHROM- MANGAN- + + BARIUM, BORON, IUM, COPPER, IRON, LEAD, ESE, NITRATE AMMONIA ORG-N, PHOS- WATER, WATER, WATER, WATER, WATER, WATER, WATER, WATER WATER, WATER, PHORUS, ARSENIC UNFLTRD UNFLTRD CADMIUM UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD WATER, WATER RECOV- RECOV- WATER, RECOV- RECOV- RECOV- RECOV- RECOV- DATE MG/L MG/L MG/L UNFLTRD UNFLTRD ERABLE, ERABLE, UNFLTRD ERABLE, ERABLE, ERABLE, ERABLE, ERABLE, AS N AS N AS N MG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L (00630) (00610) (00625) (00665) (01002) (01007) (01022) (01027) (01034) (01042) (01045) (01051) (01055) DEC 12... .770 <.01 E.30 E.02 <2 37.2 20 <.1 <.8 <10 300 <1 61.6 MAR 11... .400 .07 <.20 <.02 -- -- -- -- -- -- -- -- -- SEP 06... .540 .10 .40 .10 <2 7.3 30 <.1 1.9 <10 M M <2.4 PHEN- MERCURY SILVER, ZINC, OLIC WATER, SELEN- WATER, WATER, COM- UNFLTRD IUM, UNFLTRD UNFLTRD CYANIDE POUNDS, MBAS, RECOV- WATER, RECOV- RECOV- WATER WATER, WATER, DATE ERABLE, UNFLTRD ERABLE, ERABLE, UNFLTRD UNFLTRD UNFLTRD UG/L UG/L UG/L UG/L MG/L UG/L MG/L (71900) (01147) (01077) (01092) (00720) (32730) (38260) DEC 12... <.01 <2 <.3 <20 <.01 <16 <.05 MAR 11... -- -- -- -- -- -- -- SEP 06... .01 <2 <.3 <20 <.01 <16 <.05 < -- Less than E -- Estimated value M -- Presence verified, not quantified 143 RIO GRANDE DE ARECIBO BASIN 50027600 RIO GRANDE DE ARECIBO NEAR SAN PEDRO, PR LOCATION.--Lat 18°23'55", long 66°41'29", Hydrologic Unit 21010002, on left side of old Highway 10, 7.2 mi (11.6 km) north of Lago Dos Bocas Dam, 5.4 mi (8.69 km) from Plaza Rosario at Arecibo town and 3.8 mi (6.11 km) east from La Esperanza School. DRAINAGE AREA.--173.7 mi2 (449 km2) approximately, of which an undetermined amount does not contribute directly to surface runoff. WATER-DISCHARGE RECORDS PERIOD OF RECORD.--February 1959 to February 1962 yearly measurements only, May 2001 to current year. GAGE.--Water-stage recorder. Elevation of gage is 49.2 ft (15 m), from topographic map. REMARKS.--Records fair except those for estimated daily discharges, which are poor. Flow affected by Lago Dos Bocas Dam 7.2 mi (11.6 km) upstream from gage. Gage-height satellite telemetry at station. Discharge, cubic feet per second WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 609 502 270 123 52 63 237 1540 147 271 165 205 2 457 e384 318 202 113 115 141 1400 67 225 245 319 3 100 195 458 299 159 134 188 1390 138 379 230 1200 4 153 337 438 323 265 171 262 1140 88 234 347 901 5 163 256 655 179 108 53 272 851 437 232 488 669 6 109 465 633 200 94 164 931 882 638 216 238 485 7 239 531 296 485 64 211 950 742 202 205 260 462 8 824 7130 477 260 54 210 692 692 197 280 e278 189 9 783 3370 519 243 50 210 447 704 203 357 e230 335 10 332 1330 691 238 367 286 660 775 180 466 225 338 11 141 717 554 133 150 219 456 677 366 385 261 334 12 757 489 411 283 132 204 567 630 210 399 962 228 13 322 449 363 238 235 204 331 520 545 180 678 229 14 215 454 229 e301 220 196 224 531 348 275 229 741 15 603 620 216 e280 123 178 469 967 197 e340 443 607 16 202 418 281 e200 280 229 438 522 197 e326 300 176 17 280 213 659 e136 146 112 524 798 529 176 173 348 18 175 218 1070 e236 103 96 343 234 286 613 e213 162 19 e228 347 517 e351 62 155 437 222 244 320 365 651 20 e159 439 195 e333 120 58 382 330 247 185 e222 752 21 162 519 534 e281 211 114 1360 606 142 202 575 273 22 300 457 507 e231 206 212 432 548 154 232 192 246 23 390 584 484 250 209 247 782 525 190 e283 472 670 24 571 416 600 322 150 213 1640 392 182 201 246 578 25 e493 302 280 e430 242 264 2000 401 e174 181 566 80 26 e259 473 474 e338 213 203 1610 202 e193 264 290 146 27 101 683 484 e289 218 66 1400 344 e163 57 508 302 28 221 162 281 e341 142 51 2640 204 279 130 371 162 29 553 198 264 e178 --- 52 2040 385 193 393 e408 412 30 757 203 255 e283 --- 57 2850 387 203 192 e282 370 31 449 --- 317 96 --- 210 --- 299 --- 189 303 --- TOTAL 11107 22861 13730 8082 4488 4957 25705 19840 7339 8388 10765 12570 MEAN 358 762 443 261 160 160 857 640 245 271 347 419 MAX 824 7130 1070 485 367 286 2850 1540 638 613 962 1200 MIN 100 162 195 96 50 51 141 202 67 57 165 80 AC-FT 22030 45340 27230 16030 8900 9830 50990 39350 14560 16640 21350 24930 CFSM 2.06 4.39 2.55 1.50 0.92 0.92 4.93 3.68 1.41 1.56 2.00 2.41 IN. 2.38 4.90 2.94 1.73 0.96 1.06 5.51 4.25 1.57 1.80 2.31 2.69 STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 2001 - 2002, BY WATER YEAR (WY) MEAN 358 762 443 261 160 160 857 640 261 287 344 441 MAX 358 762 443 261 160 160 857 640 278 303 347 464 (WY) 2002 2002 2002 2002 2002 2002 2002 2002 2001 2001 2002 2001 MIN 358 762 443 261 160 160 857 640 245 271 341 419 (WY) 2002 2002 2002 2002 2002 2002 2002 2002 2002 2002 2001 2002 SUMMARY STATISTICS FOR 2001 CALENDAR YEAR FOR 2002 WATER YEAR WATER YEARS 2001 - 2002 ANNUAL TOTAL 149832 ANNUAL MEAN 410 410 HIGHEST ANNUAL MEAN 410 2002 LOWEST ANNUAL MEAN 410 2002 HIGHEST DAILY MEAN 7130 Nov 8 7130 Nov 8 2001 LOWEST DAILY MEAN 50 Feb 9 47 Jun 1 2001 ANNUAL SEVEN-DAY MINIMUM 113 Feb 3 113 Feb 3 2002 MAXIMUM PEAK FLOW 14900 Nov 8 14900 Nov 8 2001 MAXIMUM PEAK STAGE 14.72 Nov 8 14.72 Nov 8 2001 ANNUAL RUNOFF (AC-FT) 297200 297400 ANNUAL RUNOFF (CFSM) 2.36 2.36 ANNUAL RUNOFF (INCHES) 32.09 32.11 10 PERCENT EXCEEDS 697 678 50 PERCENT EXCEEDS 280 284 90 PERCENT EXCEEDS 137 127 e Estimated 144 RIO GRANDE DE ARECIBO BASIN 50027600 RIO GRANDE DE ARECIBO NEAR SAN PEDRO, PR--Continued O N D 2001 J F M A M J J A S 2002 10 20 50 100 100 200 500 1000 1000 2000 5000 10,000 DISCHARGE, IN CUBIC FEET PER SECOND 145 RIO GRANDE DE ARECIBO BASIN 50027600 RIO GRANDE DE ARECIBO NEAR SAN PEDRO, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--February 1959 to February 1962 yearly measurements only, May 2001 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: October 2001 to September 2002. INSTRUMENTATION.-- USDH-48 sediment sampler and automatic sediment sampler since 2001. REMARKS.--Sediment samples were collected by local observer on a weekly basis. During high flow events sediment samples were collected with automatic sediment sampler. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATION: Maximum daily mean, 671 mg/L November 9, 2001; Minimum daily mean, 1 mg/L several days. SEDIMENT LOADS: Maximum daily mean, 14,700 tons (13,336 tonnes) November 8, 2001; Minimum daily mean, 0.19 ton (0.17 tonne) July 27, 2002. EXTREMES FOR CURRENT YEAR 2002.-- SEDIMENT CONCENTRATION: Maximum daily mean, 671 mg/L November 9, 2001; Minimum daily mean, 1 mg/L several days. SEDIMENT LOADS: Maximum daily mean, 14,700 tons (13,336 tonnes) November 8, 2001; Minimum daily mean, 0.19 ton (0.17 tonne) July 27, 2002. SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) OCTOBER NOVEMBER DECEMBER 1 609 6 11 502 8 15 270 61 113 2 457 6 8.6 e384 e5 e1.9 318 88 127 3 100 7 1.8 195 5 2.6 458 59 98 4 153 4 2.4 337 5 4.5 438 90 194 5 163 4 2.4 256 5 3.5 655 143 389 6 109 4 1.4 465 24 67 633 120 319 7 239 4 3.7 531 32 79 296 57 74 8 824 6 15 7130 512 14700 477 88 201 9 783 5 11 3370 671 6920 519 136 260 10 332 4 4.1 1330 219 824 691 127 341 11 141 4 1.5 717 133 296 554 98 247 12 757 5 14 489 118 213 411 78 159 13 322 5 4.7 449 116 219 363 56 117 14 215 4 3.1 454 125 213 229 46 63 15 603 7 15 620 156 347 216 34 61 16 202 6 5.6 418 119 198 281 48 88 17 280 11 8.3 213 78 61 659 108 295 18 175 5 4.0 218 79 98 1070 144 633 19 e228 e8 e4.6 347 95 152 517 48 109 20 e159 e7 e4.6 439 121 247 195 10 4.7 21 162 8 4.6 519 119 268 534 6 8.0 22 300 8 8.4 457 115 236 507 5 6.8 23 390 7 9.8 584 124 288 484 5 6.5 24 571 9 21 416 103 198 600 5 8.1 25 e493 e8 e5.6 302 85 114 280 5 3.6 26 e259 e6 e1.4 473 133 270 474 5 5.8 27 101 6 1.6 683 144 453 484 4 5.5 28 221 6 3.6 162 42 47 281 4 4.1 29 553 6 9.0 198 45 53 264 5 4.9 30 757 9 25 203 52 49 255 5 4.7 31 449 7 10 --- --- --- 317 7 6.6 TOTAL 11107 --- 226.8 22861 --- 26637.5 13730 --- 3957.3 146 RIO GRANDE DE ARECIBO BASIN 50027600 RIO GRANDE DE ARECIBO NEAR SAN PEDRO, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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 FEBRUARY MARCH 1 123 5 1.9 52 5 0.66 63 4 0.69 2 202 4 3.4 113 4 1.8 115 4 1.4 3 299 6 5.8 159 5 2.5 134 15 6.7 4 323 6 6.8 265 6 5.5 171 23 11 5 179 10 5.1 108 4 1.0 53 19 2.8 6 200 8 4.9 94 4 1.0 164 17 11 7 485 9 12 64 4 0.69 211 29 17 8 260 6 4.9 54 4 0.58 210 29 17 9 243 6 4.9 50 4 0.54 210 30 17 10 238 6 5.0 367 5 6.5 286 32 25 11 133 7 2.6 150 6 3.0 219 34 19 12 283 5 3.8 132 6 2.7 204 35 18 13 238 7 8.1 235 6 5.0 204 36 19 14 e301 e20 e19 220 5 4.2 196 38 23 15 e280 e4 e3.1 123 4 1.6 178 39 21 16 e200 e6 e8.2 280 4 3.8 229 31 18 17 e136 e3 e2.7 146 4 2.7 112 28 8.5 18 e236 e5 e4.1 103 4 1.1 96 28 8.9 19 e351 e5 e5.1 62 4 0.67 155 33 21 20 e333 e5 e4.3 120 4 1.9 58 29 4.5 21 e281 e4 e2.9 211 6 4.0 114 34 11 22 e231 e3 e3.7 206 5 3.6 212 33 25 23 250 e3 e3.6 209 4 3.1 247 35 34 24 322 e3 e4.5 150 5 2.3 213 32 24 25 e430 e8 e10 242 4 3.8 264 31 25 26 e338 e6 e6.8 213 6 4.2 203 31 20 27 e289 e5 e3.8 218 7 4.8 66 24 4.4 28 e341 e6 e6.8 142 6 3.2 51 23 3.1 29 e178 e5 e2.5 --- --- --- 52 22 3.1 30 e283 e4 e3.8 --- --- --- 57 21 3.3 31 96 e5 1.3 --- --- --- 210 23 18 TOTAL 8082 --- 165.4 4488 --- 76.44 4957 --- 441.39 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) APRIL MAY JUNE 1 237 26 24 1540 241 1010 147 14 6.0 2 141 32 15 1400 226 857 67 18 3.3 3 188 23 16 1390 221 829 138 23 8.1 4 262 26 26 1140 203 642 88 23 5.3 5 272 27 30 851 106 290 437 35 63 6 931 26 63 882 79 238 638 64 167 7 950 24 62 742 58 150 202 24 27 8 692 24 48 692 62 143 197 19 23 9 447 23 30 704 64 174 203 17 23 10 660 26 52 775 58 157 180 18 19 11 456 23 31 677 51 153 366 26 46 12 567 24 41 630 49 123 210 14 19 13 331 24 22 520 41 90 545 38 86 14 224 27 16 531 40 92 348 13 15 15 469 29 38 967 64 190 197 5 2.4 16 438 29 35 522 36 77 197 4 2.1 17 524 26 38 798 39 128 529 30 72 18 343 22 21 234 22 33 286 42 37 19 437 26 33 222 22 33 244 28 20 20 382 27 28 330 27 42 247 25 20 21 1360 27 100 606 42 102 142 19 9.0 22 432 28 32 548 45 104 154 16 7.2 23 782 171 654 525 30 68 190 15 9.9 24 1640 268 1220 392 16 28 182 12 8.1 25 2000 259 1510 401 8 18 e174 e10 e5.3 26 1610 253 1160 202 5 6.0 e193 e6 e0.57 27 1400 208 788 344 7 12 e163 e6 e3.0 28 2640 331 2400 204 6 6.4 279 9 11 29 2040 283 2030 385 9 9.6 193 35 24 30 2850 370 3150 387 13 19 203 20 14 31 --- --- --- 299 12 12 --- --- --- TOTAL 25705 --- 13713 19840 --- 5836.0 7339 --- 756.27 147 RIO GRANDE DE ARECIBO BASIN 50027600 RIO GRANDE DE ARECIBO NEAR SAN PEDRO, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) JULY AUGUST SEPTEMBER 1 271 17 20 165 4 2.9 205 9 9.4 2 225 13 12 245 5 5.0 319 11 23 3 379 11 15 230 4 4.5 1200 69 249 4 234 9 8.9 347 5 7.8 901 44 146 5 232 7 8.0 488 6 13 669 30 58 6 216 8 8.2 238 5 5.2 485 21 37 7 205 7 7.1 260 7 5.4 462 13 27 8 280 7 7.0 e278 e4 e2.8 189 9 8.3 9 357 9 12 e230 e3 e0.29 335 11 15 10 466 11 18 225 4 4.5 338 9 14 11 385 10 14 261 4 5.2 334 11 14 12 399 11 15 962 94 366 228 9 11 13 180 8 4.4 678 93 244 229 9 11 14 275 9 7.9 229 36 66 741 55 181 15 e340 e7 e3.6 443 67 170 607 57 164 16 e326 e6 e3.1 300 50 76 176 8 6.0 17 176 6 3.6 173 11 24 348 27 47 18 613 8 19 e213 e49 e66 162 11 13 19 320 6 8.2 365 37 72 651 72 197 20 185 3 2.9 e222 e25 e37 752 83 249 21 202 3 3.8 575 69 171 273 25 40 22 232 1 1.7 192 19 26 246 28 53 23 e283 e1 e1.4 472 257 464 670 65 161 24 201 3 3.5 246 28 51 578 70 180 25 181 2 2.8 566 89 154 80 6 1.3 26 264 3 4.2 290 33 56 146 5 2.1 27 57 1 0.19 508 58 140 302 9 12 28 130 2 2.5 371 57 74 162 8 7.0 29 393 4 6.7 e408 e7 e2.0 412 11 18 30 192 4 3.9 e282 e6 e1.2 370 14 20 31 189 5 4.0 303 25 50 --- --- --- TOTAL 8388 --- 232.59 10765 --- 2366.79 12570 --- 1974.1 YEAR 149832 56383.58 e Estimated WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT Sus- Suspnd. pended Sus- sedi- Instan- sedi- pended ment, taneous ment sedi- sieve dis- concen- ment diametr Date Time charge, tration load, percent cfs mg/L tons/d <.063mm (00061) (80154) (80155) (70331) APR 25... 0113 2360 236 1500 88 148 RIO GRANDE DE ARECIBO BASIN 50027750 RIO GRANDE DE ARECIBO ABOVE ARECIBO, PR LOCATION.--Lat 18°25'22", long 66°41'58", Hydrologic Unit 21010002, 0.5 mi (0.8 km) upstream from Río Tanamá, 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 Dos Bocas. DRAINAGE AREA.--174 mi2 (451 km2), approximately, of which an undetermined amount does not contribute directly to surface runoff. WATER-DISCHARGE RECORDS PERIOD OF RECORD.--April 1982 to September 2002. (discontinued) GAGE.--Water-stage recorder. Elevation of gage is 30 ft (9 m), from topographic map. REMARKS.--Records 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 WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 355 355 144 149 11 9.5 90 1690 e139 e99 e83 e134 2 357 236 250 33 9.7 10 189 1580 e63 e82 e80 e148 3 86 16 358 160 23 9.5 55 1500 e66 e118 e123 e706 4 15 175 387 209 57 52 250 e1070 e73 e119 e151 e518 5 86 144 541 150 20 6.6 298 e481 e159 e88 e159 e483 6 5.8 175 498 63 8.1 11 923 e533 e277 e85 e198 e340 7 28 395 334 298 7.4 67 1000 e460 e187 e91 e105 e204 8 369 1690 342 199 6.7 109 967 e403 e105 e105 e112 e187 9 473 1830 418 164 9.7 102 714 e397 e102 e113 e82 e144 10 379 1030 510 154 32 148 716 e560 e103 e211 e71 e148 11 159 582 449 109 127 164 652 e333 e121 e191 e147 e215 12 404 409 353 95 14 112 576 e378 e140 e227 e358 e171 13 294 252 291 181 73 94 482 e191 e212 e129 e357 e118 14 203 385 253 272 131 91 390 e180 e217 e112 e231 e250 15 252 462 136 200 89 106 574 e300 e119 e154 e108 e429 16 214 290 204 160 87 23 641 e525 e98 e145 e209 e142 17 158 208 474 75 134 112 730 e539 e204 e103 e90 e159 18 49 80 512 167 36 8.2 640 e293 e165 e160 e98 e204 19 87 198 573 158 21 47 808 e175 e134 e221 e149 e362 20 17 227 327 148 17 11 913 e184 e126 e106 e166 e446 21 80 320 394 119 193 18 1580 e314 e92 e76 e212 e298 22 42 259 498 135 191 36 898 e327 e51 e88 e157 e143 23 182 386 416 142 172 109 1030 e301 e71 e121 e176 e279 24 325 223 501 151 130 168 1470 e269 e77 e83 e126 e343 25 263 118 271 201 79 192 1680 e211 e73 e70 e244 e136 26 125 281 333 155 134 139 1620 e166 e84 e112 e165 e66 27 17 307 361 112 97 51 1440 e187 e66 e44 e214 e98 28 20 273 234 135 106 5.8 2050 e138 e101 e33 e221 e161 29 302 82 187 55 --- 5.7 1580 e176 e94 e129 e233 e134 30 461 148 183 103 --- 5.6 2340 e200 e72 e122 e144 e181 31 332 --- 203 43 --- 23 --- e179 --- e75 e158 --- TOTAL 6139.8 11536 10935 4495 2015.6 2045.9 27296 14240 3591 3612 5127 7347 MEAN 198 385 353 145 72.0 66.0 910 459 120 117 165 245 MAX 473 1830 573 298 193 192 2340 1690 277 227 358 706 MIN 5.8 16 136 33 6.7 5.6 55 138 51 33 71 66 AC-FT 12180 22880 21690 8920 4000 4060 54140 28250 7120 7160 10170 14570 CFSM 1.14 2.21 2.03 0.83 0.41 0.38 5.23 2.64 0.69 0.67 0.95 1.41 IN. 1.31 2.47 2.34 0.96 0.43 0.44 5.84 3.04 0.77 0.77 1.10 1.57 STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1982 - 2002, BY WATER YEAR (WY) MEAN 558 493 289 229 204 193 334 511 322 229 254 498 MAX 1984 1413 570 437 428 351 910 2000 683 374 474 1479 (WY) 1986 1986 1988 1988 1988 1985 2002 1986 1987 1987 1988 1996 MIN 171 123 72.4 54.8 36.9 46.8 28.8 178 69.3 62.7 82.8 99.9 (WY) 1995 1995 1995 2001 2001 2001 2001 1994 1994 1994 1994 1994 SUMMARY STATISTICS FOR 2001 CALENDAR YEAR FOR 2002 WATER YEAR WATER YEARS 1982 - 2002 ANNUAL TOTAL 66802.5 98380.3 ANNUAL MEAN 183 270 342 HIGHEST ANNUAL MEAN 729 1986 LOWEST ANNUAL MEAN 132 1994 HIGHEST DAILY MEAN 1830 Nov 9 2340 Apr 30 14800 May 18 1985 LOWEST DAILY MEAN 1.2 Jan 8 5.6 Mar 30 0.91 Dec 25 2000 ANNUAL SEVEN-DAY MINIMUM 9.0 Apr 5 19 Feb 2 9.0 Apr 5 2001 MAXIMUM PEAK FLOW 3250 Apr 30 45800 May 18 1985 MAXIMUM PEAK STAGE 11.21 Apr 30 18.22 May 18 1985 ANNUAL RUNOFF (AC-FT) 132500 195100 247900 ANNUAL RUNOFF (CFSM) 1.05 1.55 1.97 ANNUAL RUNOFF (INCHES) 14.28 21.03 26.72 10 PERCENT EXCEEDS 408 535 710 50 PERCENT EXCEEDS 136 161 222 90 PERCENT EXCEEDS 7.5 40 52 e Estimated 149 RIO GRANDE DE ARECIBO BASIN 50027750 RIO GRANDE DE ARECIBO ABOVE ARECIBO, PR--Continued O N D 2001 J F M A M J J A S 2002 1 2 5 10 10 20 50 100 100 200 500 1000 1000 2000 5000 10,000 DISCHARGE, IN CUBIC FEET PER SECOND 150 RIO GRANDE DE ARECIBO BASIN 50028000 RIO TANAMA NEAR UTUADO, PR LOCATION.--Lat 18°18'02", long 66°46'58", Hydrologic Unit 21010001, on downstream side of left abutment of bridge on Highway 111, 1.2 mi (1.9 km) upstream from natural tunnel, 1.5 mi (2.4 km) northeast of Angeles, and 5.8 mi (9.3 km) northwest of Utuado. DRAINAGE AREA.--18.4 mi2 (47.7 km2). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--June 1944 to June 1958 (daily stage and two to four measurements per month by Puerto Rico Water Resources Authority), November 1959 to current year. GAGE.--Water-stage recorder and crest-stage gage. Datum of gage is 938.3 ft (286.0 m) above mean sea level. Datum of gage was increased by 3.0 ft (0.91 m) on October 1978. REMARKS.--Records fair except those for estimated daily discharges, which are poor. Discharge, cubic feet per second WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 42 105 61 41 27 20 121 181 63 33 64 37 2 40 89 61 42 26 20 72 225 62 31 77 98 3 48 81 108 41 26 19 46 147 64 33 48 217 4 41 72 116 41 26 19 40 125 66 31 55 102 5 38 70 75 50 27 19 209 113 63 29 48 92 6 37 74 61 56 25 19 240 115 61 37 43 62 7 37 119 57 45 25 19 136 104 58 34 36 50 8 44 841 54 42 24 22 279 97 55 37 34 47 9 37 333 53 44 24 20 109 265 54 50 66 45 10 215 189 52 40 24 55 80 173 52 46 53 62 11 133 150 84 39 24 60 68 132 53 55 71 51 12 62 133 85 36 23 39 60 115 60 80 50 43 13 56 120 63 35 22 29 55 108 55 45 86 41 14 48 243 59 35 22 23 51 101 47 62 58 40 15 49 138 54 34 23 22 54 166 47 48 43 52 16 42 114 120 34 22 31 78 e182 46 38 37 60 17 42 105 67 34 21 42 71 e103 46 37 35 43 18 46 96 56 33 22 23 148 e94 45 35 78 162 19 41 90 53 33 43 24 217 e90 46 34 42 78 20 37 86 48 31 26 21 231 e88 44 34 46 68 21 35 83 104 32 23 20 149 e84 41 34 39 50 22 100 79 54 31 21 20 107 e81 38 40 41 46 23 171 76 72 31 21 20 229 e78 37 36 45 44 24 202 81 69 33 21 19 271 e75 35 34 47 45 25 127 72 54 30 21 18 277 e74 43 33 39 43 26 78 70 50 30 21 20 195 e71 45 31 61 40 27 173 68 47 30 21 22 305 e69 42 30 39 40 28 150 67 44 29 20 26 199 e67 36 58 35 39 29 108 75 43 29 --- 23 235 e65 33 42 35 38 30 81 65 42 28 --- 23 212 e65 33 33 44 37 31 73 --- 42 27 --- 117 --- e62 --- 44 48 --- TOTAL 2433 3984 2008 1116 671 874 4544 3515 1470 1244 1543 1872 MEAN 78.5 133 64.8 36.0 24.0 28.2 151 113 49.0 40.1 49.8 62.4 MAX 215 841 120 56 43 117 305 265 66 80 86 217 MIN 35 65 42 27 20 18 40 62 33 29 34 37 AC-FT 4830 7900 3980 2210 1330 1730 9010 6970 2920 2470 3060 3710 CFSM 4.27 7.22 3.52 1.96 1.30 1.53 8.23 6.16 2.66 2.18 2.71 3.39 IN. 4.92 8.05 4.06 2.26 1.36 1.77 9.19 7.11 2.97 2.52 3.12 3.78 STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1960 - 2002, BY WATER YEAR (WY) MEAN 81.7 70.5 43.8 30.4 26.0 25.1 38.3 58.4 44.3 36.3 47.7 78.2 MAX 195 159 121 71.0 50.8 71.2 151 193 117 65.7 110 208 (WY) 1990 1969 1966 1997 1996 1972 2002 1963 1999 1981 1979 1998 MIN 25.4 25.1 18.1 14.7 13.2 11.0 9.70 12.4 15.6 9.18 15.9 25.0 (WY) 1963 1995 1998 1998 1965 1984 1984 1977 1994 1994 1994 1994 SUMMARY STATISTICS FOR 2001 CALENDAR YEAR FOR 2002 WATER YEAR WATER YEARS 1960 - 2002 ANNUAL TOTAL 18697 25202 ANNUAL MEAN 51.2 69.0 48.5 HIGHEST ANNUAL MEAN 71.7 1999 LOWEST ANNUAL MEAN 20.7 1994 HIGHEST DAILY MEAN 841 Nov 8 841 Nov 8 3260 Sep 22 1998 LOWEST DAILY MEAN 12 Mar 31 18 Mar 25 5.4 Aug 4 1994 ANNUAL SEVEN-DAY MINIMUM 13 Mar 27 19 Mar 1 6.4 Jul 29 1994 MAXIMUM PEAK FLOW 3400 Nov 8 23500 Sep 22 1998 MAXIMUM PEAK STAGE 12.44 Nov 8 21.24 Sep 22 1998 INSTANTANEOUS LOW FLOW 5.4 Aug 4 1994 ANNUAL RUNOFF (AC-FT) 37090 49990 35110 ANNUAL RUNOFF (CFSM) 2.78 3.75 2.63 ANNUAL RUNOFF (INCHES) 37.80 50.95 35.78 10 PERCENT EXCEEDS 99 133 87 50 PERCENT EXCEEDS 35 48 34 90 PERCENT EXCEEDS 16 23 16 e Estimated 151 RIO GRANDE DE ARECIBO BASIN 50028000 RIO TANAMA NEAR UTUADO, PR--Continued O N D 2001 J F M A M J J A S 2002 10 20 50 100 100 200 500 1000 DISCHARGE, IN CUBIC FEET PER SECOND 152 RIO GRANDE DE ARECIBO BASIN 50028000 RIO TANAMA NEAR UTUADO, PR WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1958 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED SEDIMENT DISCHARGE: January 1968 to current year. INSTRUMENTATION.--USDH-48 sediment sampler since October 1968. Automatic sediment sampler since 1990. REMARKS.--Sediment samples were collected by a local observer on a weekly basis. During high flow events sediment samples were collected with automatic sediment sampler. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATIONS: Maximum daily mean, 20,400 mg/L November 27, 1968; Minimum daily mean, 1 mg/L several days during several years. SEDIMENT LOADS: Maximum daily mean, 240,000 tons (218,000 tonnes) September 22, 1998; Minimum daily mean, <0.01 ton (<0.01 tonne) several days during several years. EXTREMES FOR CURRENT YEAR 2002.-- SEDIMENT CONCENTRATIONS: Maximum daily mean, 9,390 mg/L November 8, 2001; Minimum daily mean, 3 mg/L February 27, 28, 2002. SEDIMENT LOADS: Maximum daily mean, 36,000 tons (32,659 tonnes) November 8, 2001; Minimum daily mean, 0.17 ton (0.15 tonne) February 28, 2002. WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 TURBID- FECAL FECAL SPECIF. PH, ITY, DIS- COD, COLI- STREP- HARD- INSTAN- CONDUC- WATER, WAT UNF SOLVED HIGH FORM, TOCOCCI NESS, TANEOUS TANCE, UNFLTRD TEMPER- LAB, DIS- OXYGEN, LEVEL, M-FC KF WATER, CALCIUM DIS- WAT UNF FIELD, ATURE, HACH SOLVED PERCENT WATER, 0.7U MF MF, UNFLTRD WATER, DATE TIME CHARGE, US/CM STD WATER, 2100AN OXYGEN, OF SAT- UNFLTRD COL/ COL/ MG/L AS FLTRD, CFS 25 DEGC UNITS DEG C NTU MG/L URATION MG/L 100 ML 100 ML CACO3 MG/L (00061) (00095) (00400) (00010) (99872) (00300) (00301) (00340) (31625) (31673) (00900) (00915) DEC 13... 1115 62 154 6.8 22.2 69 8.3 100 10 5900 4800 54 13.6 FEB 21... 0910 24 176 7.1 19.0 26 7.8 87 <10 180 280 -- -- SEP 11... 0940 48 138 6.4 23.0 120 8.6 102 <10 5600 7900 51 12.8 ANC, RESIDUE RESIDUE WAT UNF WATER, TOTAL MAGNES- POTAS- FIXED CHLOR- FLUOR- FLTRD, AT 105 IUM, SODIUM, SODIUM SIUM, END PT, SULFIDE SULFATE IDE, IDE, SILICA, SUM OF RESIDUE DEG. C, WATER, WATER, ADSORP- WATER, FIELD, WATER WATER, WATER, WATER, WATER, CONSTI- WATER, SUS- DATE FLTRD, FLTRD, TION FLTRD, MG/L AS UNFLTRD FLTRD, FLTRD, FLTRD, FLTRD, TUENTS FLTRD, PENDED, MG/L MG/L RATIO MG/L CACO3 MG/L MG/L MG/L MG/L MG/L MG/L TONS/D MG/L (00925) (00930) (00931) (00935) (00410) (00745) (00945) (00940) (00950) (00955) (70301) (70302) (00530) DEC 13... 4.92 6.63 .4 2.11 44 <1.0 8.8 7.28 <.1 21.9 92 15.5 88 FEB 21... -- -- -- -- 52 -- -- -- -- -- -- -- 20 SEP 11... 4.64 6.63 .4 1.94 41 .2 9.1 6.97 <.10 20.8 87 11.4 74 NITRITE AMMONIA CHROM- + + BARIUM, BORON, IUM, COPPER, IRON, LEAD, NITRITE NITRATE AMMONIA ORG-N, PHOS- WATER, WATER, WATER, WATER, WATER, WATER, WATER, WATER WATER, WATER, PHORUS, ARSENIC UNFLTRD UNFLTRD CADMIUM UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD WATER, WATER RECOV- RECOV- WATER, RECOV- RECOV- RECOV- RECOV- DATE MG/L MG/L MG/L MG/L UNFLTRD UNFLTRD ERABLE, ERABLE, UNFLTRD ERABLE, ERABLE, ERABLE, ERABLE, AS N AS N AS N AS N MG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L (00615) (00630) (00610) (00625) (00665) (01002) (01007) (01022) (01027) (01034) (01042) (01045) (01051) DEC 13... <.01 .550 .03 E.30 E.04 <2 37.1 E20 <.1 1.8 M 1500 M FEB 21... <.01 1.10 <.01 <.20 .05 -- -- -- -- -- -- -- -- SEP 11... .01 .920 .02 .40 .08 <2 38.5 E20 <.1 2.5 E10 1570 1 MANGAN- PHEN- ESE, MERCURY SILVER, ZINC, OLIC WATER, WATER, SELEN- WATER, WATER, COM- UNFLTRD UNFLTRD IUM, UNFLTRD UNFLTRD CYANIDE POUNDS, MBAS, RECOV- RECOV- WATER, RECOV- RECOV- WATER WATER, WATER, DATE ERABLE, ERABLE, UNFLTRD ERABLE, ERABLE, UNFLTRD UNFLTRD UNFLTRD UG/L UG/L UG/L UG/L UG/L MG/L UG/L MG/L (01055) (71900) (01147) (01077) (01092) (00720) (32730) (38260) DEC 13... 96.3 <.01 <2 <.3 E10 <.01 <16 <.05 FEB 21... -- -- -- -- -- -- -- -- SEP 11... 95.6 .01 <2 <.3 E30 <.01 <16 <.05 < -- Less than E -- Estimated value M -- Presence verified, not quantified 153 RIO GRANDE DE ARECIBO BASIN 50028000 RIO TANAMA NEAR UTUADO, PR--Continued WATER-QUALITY RECORDS SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) OCTOBER NOVEMBER DECEMBER 1 42 36 4.1 105 288 176 61 7 1.2 2 40 32 3.5 89 181 58 61 7 1.1 3 48 96 14 81 82 22 108 204 115 4 41 134 15 72 19 3.7 116 525 634 5 38 51 5.3 70 18 3.4 75 139 35 6 37 39 3.9 74 18 3.6 61 39 6.3 7 37 39 3.8 119 498 283 57 36 5.6 8 44 59 7.9 841 9390 36000 54 33 4.8 9 37 38 3.8 333 1340 1310 53 29 4.1 10 215 2010 5550 189 412 212 52 25 3.6 11 133 801 581 150 222 91 84 249 138 12 62 107 19 133 60 22 85 202 60 13 56 87 17 120 29 9.4 63 96 17 14 48 62 8.5 243 918 1460 59 75 12 15 49 57 9.2 138 332 133 54 70 10 16 42 51 5.7 114 162 50 120 722 865 17 42 34 3.8 105 109 31 67 136 27 18 46 48 7.0 96 57 15 56 60 9.4 19 41 45 5.1 90 14 3.5 53 43 6.2 20 37 34 3.4 86 10 2.3 48 29 3.9 21 35 26 2.5 83 10 2.2 104 535 592 22 100 466 508 79 10 2.1 54 84 13 23 171 1360 2170 76 10 2.1 72 144 35 24 202 1530 3120 81 10 2.2 69 121 23 25 127 514 248 72 11 2.1 54 80 12 26 78 145 32 70 12 2.3 50 54 7.3 27 173 1490 2050 68 13 2.3 47 31 4.0 28 150 861 665 67 11 2.1 44 24 2.9 29 108 223 83 75 10 2.0 43 21 2.4 30 81 32 7.2 65 8 1.4 42 17 2.0 31 73 17 3.3 --- --- --- 42 13 1.5 TOTAL 2433 --- 15160.0 3984 --- 39909.7 2008 --- 2654.3 154 RIO GRANDE DE ARECIBO BASIN 50028000 RIO TANAMA NEAR UTUADO, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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 FEBRUARY MARCH 1 41 10 1.2 27 7 0.50 20 4 0.23 2 42 8 0.93 26 7 0.48 20 6 0.30 3 41 8 0.90 26 7 0.47 19 7 0.35 4 41 9 0.97 26 6 0.46 19 8 0.41 5 50 10 1.3 27 6 0.46 19 9 0.46 6 56 10 1.6 25 6 0.43 19 10 0.52 7 45 11 1.4 25 6 0.41 19 11 0.57 8 42 12 1.3 24 6 0.40 22 6 0.38 9 44 12 1.4 24 7 0.43 20 6 0.32 10 40 12 1.3 24 7 0.46 55 357 195 11 39 10 1.1 24 8 0.49 60 294 104 12 36 8 0.78 23 9 0.52 39 55 6.9 13 35 6 0.55 22 11 0.66 29 25 2.1 14 35 4 0.39 22 12 0.73 23 13 0.80 15 34 4 0.38 23 9 0.53 22 13 0.79 16 34 4 0.40 22 8 0.48 31 35 4.7 17 34 5 0.45 21 8 0.46 42 90 12 18 33 5 0.47 22 8 0.48 23 41 2.6 19 33 6 0.52 43 50 7.0 24 26 1.7 20 31 6 0.53 26 17 1.3 21 18 1.0 21 32 7 0.57 23 5 0.30 20 11 0.58 22 31 7 0.60 21 5 0.27 20 10 0.53 23 31 8 0.64 21 4 0.25 20 11 0.56 24 33 8 0.71 21 4 0.24 19 11 0.58 25 30 9 0.69 21 4 0.22 18 12 0.60 26 30 9 0.73 21 4 0.21 20 12 0.64 27 30 10 0.77 21 3 0.19 22 12 0.70 28 29 10 0.78 20 3 0.17 26 12 0.84 29 29 9 0.70 --- --- --- 23 11 0.70 30 28 8 0.61 --- --- --- 23 10 0.62 31 27 7 0.52 --- --- --- 117 1220 1470 TOTAL 1116 --- 25.19 671 --- 19.00 874 --- 1811.48 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) APRIL MAY JUNE 1 121 1130 763 181 748 475 63 11 1.9 2 72 239 67 225 1420 1790 62 14 2.3 3 46 41 5.3 147 189 80 64 16 2.7 4 40 21 2.2 125 55 19 66 15 2.6 5 209 1860 3980 113 37 11 63 14 2.4 6 240 2140 2640 115 86 34 61 13 2.1 7 136 753 317 104 30 8.5 58 11 1.7 8 279 2410 2390 97 20 5.2 55 9 1.4 9 109 90 29 265 2060 5250 54 7 1.1 10 80 39 8.5 173 796 405 52 6 0.86 11 68 33 6.1 132 75 30 53 6 0.85 12 60 30 4.8 115 20 6.2 60 63 14 13 55 27 3.9 108 17 4.8 55 38 6.1 14 51 24 3.2 101 14 3.8 47 15 1.9 15 54 21 3.1 166 1440 1540 47 11 1.4 16 78 190 64 e182 e1230 e1250 46 8 0.98 17 71 171 36 e103 e382 e147 46 5 0.67 18 148 1270 1540 e94 e51 e13.0 45 6 0.75 19 217 1560 2510 e90 e11 e2.8 46 7 0.89 20 231 1730 1990 e88 e11 e2.6 44 8 0.97 21 149 586 255 e84 e11 e2.4 41 9 1.0 22 107 68 20 e81 e10 e2.3 38 10 1.1 23 229 1850 3060 e78 e10 e2.1 37 11 1.1 24 271 1690 3450 e75 e10 e2.0 35 12 1.1 25 277 1980 4010 e74 e9 e1.8 43 65 12 26 195 968 870 e71 e9 e1.6 45 59 11 27 305 2570 3740 e69 e8 e1.5 42 44 5.0 28 199 1020 660 e67 e7 e1.3 36 31 3.0 29 235 1300 1730 e65 e7 e1.2 33 27 2.4 30 212 1170 1080 e65 e6 e1.1 33 22 2.0 31 --- --- --- e62 e8 e1.4 --- --- --- TOTAL 4544 --- 35238.1 3515 --- 11096.6 1470 --- 87.27 155 RIO GRANDE DE ARECIBO BASIN 50028000 RIO TANAMA NEAR UTUADO, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) JULY AUGUST SEPTEMBER 1 33 19 1.7 64 112 24 37 8 0.82 2 31 18 1.5 77 238 132 98 541 687 3 33 23 2.3 48 51 6.5 217 1990 5670 4 31 17 1.4 55 90 17 102 353 135 5 29 16 1.3 48 122 15 92 262 120 6 37 36 4.8 43 32 3.7 62 92 16 7 34 16 1.6 36 7 0.61 50 30 4.2 8 37 14 1.4 34 6 0.54 47 10 1.2 9 50 65 14 66 207 128 45 9 1.1 10 46 54 7.1 53 73 18 62 83 20 11 55 121 33 71 192 89 51 102 14 12 80 258 103 50 56 8.1 43 75 8.6 13 45 62 8.0 86 427 427 41 72 7.8 14 62 184 63 58 81 13 40 71 7.8 15 48 142 19 43 35 3.8 52 88 14 16 38 109 11 37 31 2.9 60 90 15 17 37 97 9.6 35 30 2.8 43 49 5.6 18 35 80 7.6 78 296 214 162 1260 1980 19 34 41 3.8 42 44 4.9 78 171 43 20 34 8 0.75 46 51 7.8 68 136 36 21 34 7 0.61 39 18 1.9 50 66 9.0 22 40 33 4.5 41 26 3.4 46 61 7.7 23 36 16 1.7 45 33 4.9 44 58 6.8 24 34 8 0.71 47 50 8.6 45 54 6.7 25 33 7 0.65 39 46 4.8 43 51 6.0 26 31 7 0.59 61 178 114 40 48 5.2 27 30 7 0.58 39 28 3.0 40 44 4.7 28 58 122 42 35 9 0.85 39 41 4.2 29 42 52 6.4 35 8 0.76 38 37 3.8 30 33 7 0.63 44 46 10 37 34 3.3 31 44 45 9.1 48 51 7.3 --- --- --- TOTAL 1244 --- 363.32 1543 --- 1278.16 1872 --- 8844.52 YEAR 25274 116487.64 e Estimated WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT Sus- Suspnd. pended Sus- sedi- Instan- sedi- pended ment, taneous ment sedi- sieve dis- concen- ment diametr Date Time charge, tration load, percent cfs mg/L tons/d <.062mm (00061) (80154) (80155) (70331) OCT 22... 1900 698 4570 8610 93 APR 24... 1825 675 2820 5130 89 156 RIO GRANDE 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 house at Charco Hondo, 1.5 mi (2.4 km) upstream from mouth, and 4 mi (6 km) south of Arecibo. DRAINAGE AREA.--22.2 mi2 (57.5 km2). 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. Gage-height and precipitation satellite telemetry at station. Discharge, cubic feet per second WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 75 172 100 86 53 39 167 384 83 e53 92 168 2 72 159 97 86 56 40 173 361 95 e52 111 195 3 75 142 138 83 54 39 77 269 80 e55 106 358 4 98 130 169 80 55 40 59 204 e83 e53 94 244 5 74 117 265 83 54 40 197 172 e86 e50 147 225 6 67 113 121 102 53 41 358 153 e80 e57 99 167 7 65 189 103 95 53 42 241 144 e76 e53 76 e112 8 71 1620 95 122 50 41 541 125 e74 e57 75 97 9 73 850 91 89 50 46 276 261 e73 e70 93 93 10 331 560 85 78 51 56 179 211 e72 e66 141 104 11 298 408 94 75 53 74 139 157 e71 e90 174 127 12 267 314 127 69 51 87 100 127 e82 e120 172 105 13 174 242 126 71 50 57 81 115 e74 e80 106 81 14 130 318 103 66 47 46 78 109 e68 e100 136 79 15 104 248 93 71 47 43 76 146 e66 e78 90 95 16 106 201 134 72 45 45 87 227 e65 e70 71 124 17 91 188 208 71 47 68 98 237 e65 e64 70 107 18 97 177 152 65 46 48 119 133 e64 e60 e107 204 19 91 158 129 e63 66 46 328 110 e66 e58 157 234 20 82 143 154 57 72 42 351 101 e63 e56 130 218 21 77 139 242 e60 48 40 292 97 e60 e56 119 174 22 97 132 235 e58 44 40 189 93 e58 e68 77 114 23 228 123 189 e58 42 39 287 90 e57 e62 79 102 24 291 122 203 e62 41 40 336 84 e56 e60 99 98 25 203 111 148 e60 41 39 381 82 e64 56 148 105 26 150 110 119 e57 42 40 265 85 e70 52 102 97 27 195 108 107 e58 43 40 313 87 e63 52 111 98 28 262 107 97 e59 41 44 383 89 e56 66 84 94 29 249 113 94 e57 --- 56 314 88 e54 96 83 89 30 192 110 89 e56 --- 47 462 86 e53 57 97 89 31 158 --- 87 e55 --- 83 --- 86 --- 52 134 --- TOTAL 4543 7624 4194 2224 1395 1488 6947 4713 2077 2019 3380 4197 MEAN 147 254 135 71.7 49.8 48.0 232 152 69.2 65.1 109 140 MAX 331 1620 265 122 72 87 541 384 95 120 174 358 MIN 65 107 85 55 41 39 59 82 53 50 70 79 AC-FT 9010 15120 8320 4410 2770 2950 13780 9350 4120 4000 6700 8320 CFSM 6.60 11.4 6.09 3.23 2.24 2.16 10.4 6.85 3.12 2.93 4.91 6.30 IN. 7.61 12.78 7.03 3.73 2.34 2.49 11.64 7.90 3.48 3.38 5.66 7.03 STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1969 - 2002, BY WATER YEAR (WY) MEAN 168 142 87.9 63.1 51.3 45.0 72.8 128 92.5 67.1 85.8 141 MAX 335 260 219 167 106 76.1 232 371 236 120 168 448 (WY) 1990 1982 1982 1997 1996 1999 2002 1986 1999 1969 1998 1998 MIN 72.1 50.4 36.4 22.3 16.8 16.6 25.9 15.8 23.3 22.0 35.1 44.9 (WY) 1983 1995 1989 1989 1989 1988 1989 1989 1989 1989 1994 1994 SUMMARY STATISTICS FOR 2001 CALENDAR YEAR FOR 2002 WATER YEAR WATER YEARS 1969 - 2002 ANNUAL TOTAL 37454 44801 ANNUAL MEAN 103 123 94.1 HIGHEST ANNUAL MEAN 133 1999 LOWEST ANNUAL MEAN 46.9 1994 HIGHEST DAILY MEAN 1620 Nov 8 1620 Nov 8 6400 Sep 22 1998 LOWEST DAILY MEAN 30 Apr 2 39 Mar 1 4.2 May 28 1989 ANNUAL SEVEN-DAY MINIMUM 32 Mar 12 40 Mar 21 5.4 May 22 1989 MAXIMUM PEAK FLOW 6730 Nov 8 not determined Sep 22 1998 MAXIMUM PEAK STAGE 14.67 Nov 8 24.56 Sep 22 1998 ANNUAL RUNOFF (AC-FT) 74290 88860 68140 ANNUAL RUNOFF (CFSM) 4.62 5.53 4.24 ANNUAL RUNOFF (INCHES) 62.76 75.07 57.57 10 PERCENT EXCEEDS 189 241 180 50 PERCENT EXCEEDS 71 90 66 90 PERCENT EXCEEDS 36 48 30 e Estimated 157 RIO GRANDE DE ARECIBO BASIN 50028400 RIO TANAMA AT CHARCO HONDO, PR--Continued O N D 2001 J F M A M J J A S 2002 10 20 50 100 100 200 500 1000 1000 2000 5000 10,000 DISCHARGE, IN CUBIC FEET PER SECOND 158 RIO GRANDE DE ARECIBO BASIN 50029000 RIO GRANDE DE ARECIBO AT CENTRAL CAMBALACHE, PR LOCATION.--Lat 18°27'20", long 66°42'10", Hydrologic Unit 21010002, at bridge on unimproved road, about 500 ft (152 m) upstream from Central Cambalache, near Highway 2, 13.9 mi (22.4 km) downstream from Dos Bocas Reservoir, 1.9 mi (3.1 km) downstream from Río Tanamá junction, and 1.6 mi (2.6 km) southeast of Arecibo. DRAINAGE AREA.--200 mi2 (520 km2). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--January 1963 to January 1965 (monthly measurements only), February 1965 to April 1969 (occasional measurements only), May 1969 to September 1983, October 1996 to September 1997. GAGE.--Water-stage recorder. Datum of gage is 3.73 ft (1.14 m) above mean sea level. REMARKS.--Records poor. Flow regulated by Lago Dos Bocas dam, 13.9 mi (22.4 km) upstream. Gage-height satellite telemetry at station. Discharge, cubic feet per second WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 453 543 e270 230 67 43 196 1630 257 193 167 251 2 462 463 e330 120 63 43 257 e1590 134 165 163 272 3 199 214 384 228 75 41 96 e1470 141 223 230 1000 4 134 281 450 272 105 e89 197 e1210 150 224 273 773 5 197 278 655 229 76 e38 259 700 285 176 284 724 6 98 277 586 165 57 38 899 777 458 171 344 541 7 111 532 416 346 52 101 1010 687 327 181 203 354 8 456 5050 359 301 45 e90 985 e607 204 203 214 330 9 600 5270 442 237 43 e140 e820 e599 199 215 165 266 10 543 1780 446 218 e60 e177 e800 789 199 358 147 272 11 371 977 e500 183 e230 236 532 529 227 330 269 370 12 580 766 e400 147 42 197 e520 589 257 381 567 306 13 479 510 e340 235 89 163 e510 e330 362 240 565 226 14 339 596 e300 293 131 150 e480 e315 368 213 394 425 15 333 739 e200 274 101 153 e600 e477 225 277 208 663 16 337 513 e330 201 90 66 e700 e753 192 264 359 263 17 266 436 e520 139 136 189 e800 e770 351 199 178 289 18 173 278 e560 233 43 63 e700 480 293 291 191 354 19 208 365 e650 e217 48 95 e900 312 247 377 269 574 20 114 397 446 e205 57 55 e1000 325 235 205 296 686 21 188 523 458 e180 156 50 e2000 507 182 156 363 489 22 132 454 583 e193 157 53 e1100 524 112 175 284 266 23 329 558 486 e201 147 120 e1200 489 148 227 311 466 24 467 424 597 e212 124 168 1590 443 158 168 236 553 25 448 332 382 e260 83 185 1930 363 150 145 405 255 26 268 472 381 e212 165 150 1770 297 169 213 296 142 27 159 473 415 e170 132 90 1330 328 139 99 365 195 28 227 e411 320 e195 132 49 2530 256 197 78 375 294 29 439 e253 253 e110 --- 68 e1810 311 185 240 393 253 30 588 e300 248 e160 --- 54 3140 347 149 229 266 323 31 555 --- 260 106 --- 54 --- 315 --- 154 287 --- TOTAL 10253 24465 12967 6472 2706 3208 30661 19119 6700 6770 9067 12175 MEAN 331 816 418 209 96.6 103 1022 617 223 218 292 406 MAX 600 5270 655 346 230 236 3140 1630 458 381 567 1000 MIN 98 214 200 106 42 38 96 256 112 78 147 142 AC-FT 20340 48530 25720 12840 5370 6360 60820 37920 13290 13430 17980 24150 CFSM 1.65 4.08 2.09 1.04 0.48 0.52 5.11 3.08 1.12 1.09 1.46 2.03 IN. 1.91 4.55 2.41 1.20 0.50 0.60 5.70 3.56 1.25 1.26 1.69 2.26 STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1969 - 2002, BY WATER YEAR (WY) MEAN 782 745 524 340 277 291 386 543 441 359 428 677 MAX 1577 1529 1327 651 425 627 1022 1192 1220 854 1269 1866 (WY) 1971 2000 1982 1997 1997 1972 2002 1980 1979 1979 1979 1979 MIN 331 201 150 108 85.4 95.4 89.7 188 139 189 218 271 (WY) 2002 1998 1998 2001 2001 2001 2001 1977 1977 1997 1974 1997 SUMMARY STATISTICS FOR 2001 CALENDAR YEAR FOR 2002 WATER YEAR WATER YEARS 1969 - 2002 ANNUAL TOTAL 104821 144563 ANNUAL MEAN 287 396 489 HIGHEST ANNUAL MEAN 691 1979 LOWEST ANNUAL MEAN 261 2001 HIGHEST DAILY MEAN 5270 Nov 9 5270 Nov 9 15900 Aug 31 1979 LOWEST DAILY MEAN 42 Apr 15 38 Mar 5 38 Mar 5 2002 ANNUAL SEVEN-DAY MINIMUM 56 Mar 14 56 Mar 1 56 Mar 14 2001 MAXIMUM PEAK FLOW 10300 Nov 8 Not determined Sep 22 1998 MAXIMUM PEAK STAGE 12.05 Nov 8 19.28 Sep 22 1998 ANNUAL RUNOFF (AC-FT) 207900 286700 354500 ANNUAL RUNOFF (CFSM) 1.44 1.98 2.45 ANNUAL RUNOFF (INCHES) 19.50 26.89 33.25 10 PERCENT EXCEEDS 516 700 951 50 PERCENT EXCEEDS 214 270 344 90 PERCENT EXCEEDS 59 97 131 e Estimated 159 RIO GRANDE DE ARECIBO BASIN 50029000 RIO GRANDE DE ARECIBO AT CENTRAL CAMBALACHE, PR--Continued O N D 2001 J F M A M J J A S 2002 10 20 50 100 100 200 500 1000 1000 2000 5000 10,000 DISCHARGE, IN CUBIC FEET PER SECOND 160 RIO GRANDE DE ARECIBO BASIN 50029000 RIO GRANDE DE ARECIBO AT CENTRAL CAMBALACHE, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°27'20", long 66°42'10", Hydrologic Unit 21010002, at bridge on unimproved road, about 500 ft (152 m) upstream from Central Cambalache, near Highway 2, 8.3 mi (13.4 km) downstream from Lago Dos Bocas, 1.9 mi (3.1 km) downstream from Río Tanamá, and 1.6 mi (2.6 km) southeast of Arecibo. DRAINAGE AREA.--200 mi2 (520 km2), approximately, and excludes 6.0 mi2 (15.6km2) above Lago Garzas. PERIOD OF RECORD.--Water years 1963-66, 1969 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 TURBID- FECAL FECAL SPECIF. PH, ITY, DIS- COD, COLI- STREP- HARD- INSTAN- CONDUC- WATER, WAT UNF SOLVED HIGH FORM, TOCOCCI NESS, TANEOUS TANCE, UNFLTRD TEMPER- LAB, DIS- OXYGEN, LEVEL, M-FC KF WATER, CALCIUM DIS- WAT UNF FIELD, ATURE, HACH SOLVED PERCENT WATER, 0.7U MF MF, UNFLTRD WATER, DATE TIME CHARGE, US/CM STD WATER, 2100AN OXYGEN, OF SAT- UNFLTRD COL/ COL/ MG/L AS FLTRD, CFS 25 DEGC UNITS DEG C NTU MG/L URATION MG/L 100 ML 100 ML CACO3 MG/L (00061) (00095) (00400) (00010) (99872) (00300) (00301) (00340) (31625) (31673) (00900) (00915) DEC 20... 0930 -- 271 7.4 24.1 43 7.0 84 10 2600 964 110 36.3 MAR 07... 0945 147 273 7.4 23.8 5.9 7.4 88 <10 340 340 -- -- SEP 06... 1115 -- 230 6.7 26.6 170 6.4 80 <10 3000 2200 94 29.8 ANC, RESIDUE RESIDUE WAT UNF WATER, TOTAL MAGNES- POTAS- FIXED CHLOR- FLUOR- FLTRD, AT 105 NITRITE IUM, SODIUM, SODIUM SIUM, END PT, SULFIDE SULFATE IDE, IDE, SILICA, SUM OF DEG. C, WATER, WATER, WATER, ADSORP- WATER, FIELD, WATER WATER, WATER, WATER, WATER, CONSTI- SUS- UNFLTRD DATE FLTRD, FLTRD, TION FLTRD, MG/L AS UNFLTRD FLTRD, FLTRD, FLTRD, FLTRD, TUENTS PENDED, MG/L MG/L MG/L RATIO MG/L CACO3 MG/L MG/L MG/L MG/L MG/L MG/L MG/L AS N (00925) (00930) (00931) (00935) (00410) (00745) (00945) (00940) (00950) (00955) (70301) (00530) (00615) DEC 20... 5.21 7.76 .3 1.84 105 <1.0 10.0 9.37 <.1 17.1 151 38 <.01 MAR 07... -- -- -- -- 108 -- -- -- -- -- -- <10 <.01 SEP 06... 4.79 9.63 .4 2.11 77 <.1 10.5 10.6 E.09 15.6 129 112 .02 NITRITE AMMONIA CHROM- MANGAN- + + BARIUM, BORON, IUM, COPPER, IRON, LEAD, ESE, NITRATE AMMONIA ORG-N, PHOS- WATER, WATER, WATER, WATER, WATER, WATER, WATER, WATER WATER, WATER, PHORUS, ARSENIC UNFLTRD UNFLTRD CADMIUM UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD WATER, WATER RECOV- RECOV- WATER, RECOV- RECOV- RECOV- RECOV- RECOV- DATE MG/L MG/L MG/L UNFLTRD UNFLTRD ERABLE, ERABLE, UNFLTRD ERABLE, ERABLE, ERABLE, ERABLE, ERABLE, AS N AS N AS N MG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L (00630) (00610) (00625) (00665) (01002) (01007) (01022) (01027) (01034) (01042) (01045) (01051) (01055) DEC 20... .890 .05 .50 .08 M 34.4 E20 E.1 1.1 <10 700 M 77.2 MAR 07... .500 .01 <.20 <.02 -- -- -- -- -- -- -- -- -- SEP 06... .660 .03 .50 .09 <2 48.6 20 .1 3.7 E10 2870 3 155 PHEN- MERCURY SILVER, ZINC, OLIC WATER, SELEN- WATER, WATER, COM- UNFLTRD IUM, UNFLTRD UNFLTRD CYANIDE POUNDS, MBAS, RECOV- WATER, RECOV- RECOV- WATER WATER, WATER, DATE ERABLE, UNFLTRD ERABLE, ERABLE, UNFLTRD UNFLTRD UNFLTRD UG/L UG/L UG/L UG/L MG/L UG/L MG/L (71900) (01147) (01077) (01092) (00720) (32730) (38260) DEC 20... E.01 <2 <.3 <20 <.01 -- <.05 MAR 07... -- -- -- -- -- -- -- SEP 06... .02 <2 <.3 <20 <.01 <16 <.05 161 RIO GRANDE DE ARECIBO BASIN 50029000 RIO GRANDE DE ARECIBO AT CENTRAL CAMBALACHE, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 PESTICIDE ANALYSES CHLOR- DI- CARBO- DANE, ALPHA- CHLOR- PHENO- TECH- CHLOR- TRIBU- DIAZI- DIEL- DISUL- ENDO- PROP, 2,4,5-T 2,4-D ALDRIN, THION, NICAL, PYRIFOS PHOS, NON, DRIN, FOTON, SULFAN, WATER, WATER WATER WATER, WATER, WATER, WATER WATER, WATER, WATER, WATER, WATER, DATE TIME UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L (82183) (39740) (39730) (39330) (39786) (39350) (38932) (39040) (39570) (39380) (39011) (39388) SEP 06... 1115 <.02 <.01 .05 <.01 <.02 <.1 <.01 <.02 <.02 <.006 <.10 <.02 P,P'- HEPTA- METH- METHYL CHLOR HEPTA- MALA- OXY- PARA- P,P'- P,P'- P,P'- ENDRIN, ETHION, FONOFOS EPOXIDE CHLOR, LINDANE THION, CHLOR, THION, MIREX, DDD, DDE, DDT, WATER, WATER, WATER WATER WATER, WATER, WATER, WATER, WATER, WATER, WATER, WATER, WATER, DATE UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L (39390) (39398) (82614) (39420) (39410) (39340) (39530) (39480) (39600) (39755) (39360) (39365) (39370) SEP 06... <.01 <.01 <.01 <.009 <.01 <.006 <.10 <.020 <.01 <.006 <.007 <.006 <.009 PARA- TOXA- THION, PCBS, PHORATE SILVEX, PHENE, WATER, WATER, WATER WATER, WATER, DATE UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UG/L UG/L UG/L UG/L UG/L (39540) (39516) (39023) (39760) (39400) SEP 06... <.01 <.1 <.02 <.02 <1 < -- Less than E -- Estimated value M -- Presence verified, not quantified 162 THIS PAGE IS INTENTIONALLY BLANK 163 Figure 14. Río Grande de Manatí basin. 164 RIO GRANDE DE MANATI BASIN 50030460 RIO OROCOVIS AT OROCOVIS, PR LOCATION.--Lat 18°13'25", long 66°23'34", Hydrologic Unit 21010001, on right bank, 0.4 mi (0.6 km) south of junction of Highways 155 and 156 in Orocovis, 2.1 mi (3.4 km) upstream from Río Botijas, and 250 ft (76 m) upstream from bridge on Highway 599. DRAINAGE AREA.--5.03 mi2 (13.0 km2). PERIOD OF RECORD.--April 1981 to September 1982, October 1988 to current year. GAGE.--Water-stage recorder. Elevation of gage is 500 ft (152 m), from topographic map. REMARKS.--Records poor. Low flow affected by diversions for water supply. Gage-height and precipitation satellite telemetry at station. Discharge, cubic feet per second WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 2.2 1.1 7.6 8.1 5.0 6.0 4.7 11 5.2 2.7 6.8 2.0 2 2.4 8.3 104 8.0 4.9 6.2 3.2 12 5.0 2.8 2.2 7.5 3 1.9 5.2 32 8.1 6.4 5.1 2.3 12 5.2 2.4 1.8 14 4 2.0 2.1 18 7.9 6.0 5.4 2.9 11 5.2 2.4 1.6 5.9 5 2.6 7.3 10 9.9 5.3 4.6 4.9 11 18 2.6 2.2 3.4 6 2.4 10 7.3 15 5.2 4.1 12 10 9.6 2.9 1.7 2.8 7 2.0 4.8 5.8 9.4 5.1 4.2 8.9 10 4.6 3.3 1.5 2.8 8 2.0 340 5.8 8.1 4.6 4.8 38 8.8 4.5 3.1 1.4 2.6 9 3.4 67 6.3 7.8 4.9 4.4 30 6.8 4.0 2.4 1.2 2.7 10 3.6 38 7.2 7.0 4.3 5.9 18 5.5 3.2 2.2 2.5 2.3 11 3.1 25 7.7 6.9 4.3 5.7 11 5.2 3.5 2.2 3.7 2.4 12 2.0 19 8.2 7.7 4.0 4.3 8.0 e6.2 3.5 7.1 1.9 2.3 13 1.7 15 7.5 7.8 4.2 4.6 4.4 e6.8 2.9 2.2 1.5 2.2 14 1.6 14 7.3 7.2 4.2 4.4 3.8 e6.5 3.5 2.2 1.3 3.5 15 2.7 14 7.9 6.1 3.6 4.1 5.8 e6.3 2.8 2.3 1.4 4.8 16 3.1 12 14 6.0 3.4 3.8 10 e6.4 3.2 1.9 1.2 10 17 2.3 11 11 6.1 3.2 4.1 6.7 e5.3 3.2 1.8 1.1 3.1 18 2.2 11 10 5.9 3.9 4.3 18 e4.6 4.3 2.3 1.3 5.7 19 1.7 10 11 5.9 20 5.4 11 e4.5 3.7 2.3 1.5 4.5 20 1.5 8.9 8.7 6.8 9.3 4.0 39 e5.0 3.4 2.2 1.2 29 21 1.3 8.4 13 6.2 4.5 3.7 36 e4.4 3.8 2.3 1.3 12 22 1.3 8.7 20 6.3 4.6 3.3 14 e4.4 3.5 2.3 1.7 4.1 23 1.3 8.5 41 6.0 4.4 3.4 57 e4.1 2.5 2.1 1.8 2.4 24 1.3 9.0 41 6.7 3.9 3.4 70 e3.0 3.4 2.0 1.6 8.6 25 1.3 9.3 20 6.3 4.8 3.3 116 3.7 3.7 2.1 1.7 7.2 26 1.1 8.9 13 6.0 6.7 3.2 43 3.9 2.9 2.0 1.8 5.0 27 1.2 8.3 10 5.9 5.8 3.6 25 3.8 3.3 1.9 1.8 3.4 28 2.7 8.6 9.8 6.4 5.3 3.0 16 4.0 3.0 2.1 2.0 10 29 1.8 11 9.1 5.2 --- 20 13 5.3 3.1 2.2 2.1 7.2 30 1.3 8.0 8.4 5.2 --- 9.1 12 6.5 3.0 1.6 2.5 4.0 31 1.1 --- 8.3 5.3 --- 4.1 --- 5.4 --- 2.0 2.9 --- TOTAL 62.1 712.4 490.9 221.2 151.8 155.5 644.6 203.4 130.7 75.9 60.2 177.4 MEAN 2.00 23.7 15.8 7.14 5.42 5.02 21.5 6.56 4.36 2.45 1.94 5.91 MAX 3.6 340 104 15 20 20 116 12 18 7.1 6.8 29 MIN 1.1 1.1 5.8 5.2 3.2 3.0 2.3 3.0 2.5 1.6 1.1 2.0 AC-FT 123 1410 974 439 301 308 1280 403 259 151 119 352 CFSM 0.40 4.72 3.15 1.42 1.08 1.00 4.27 1.30 0.87 0.49 0.39 1.18 IN. 0.46 5.27 3.63 1.64 1.12 1.15 4.77 1.50 0.97 0.56 0.45 1.31 STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1981 - 2002, BY WATER YEAR (WY) MEAN 16.4 11.9 7.05 6.33 4.31 2.16 6.08 12.7 4.70 3.05 4.53 22.5 MAX 58.0 39.9 17.9 34.3 15.7 5.02 21.5 45.9 17.1 9.07 12.3 83.0 (WY) 1990 2000 2000 1992 1996 2002 2002 1995 1999 1996 1989 1998 MIN 1.95 0.93 0.53 0.77 0.96 0.90 0.93 0.86 0.88 0.88 1.03 0.88 (WY) 1994 1998 1998 1995 1995 1994 1995 1997 1994 1994 1982 1994 SUMMARY STATISTICS FOR 2001 CALENDAR YEAR FOR 2002 WATER YEAR WATER YEARS 1981 - 2002 ANNUAL TOTAL 2244.22 3086.1 ANNUAL MEAN 6.15 8.46 8.39 HIGHEST ANNUAL MEAN 13.3 1999 LOWEST ANNUAL MEAN 1.49 1994 HIGHEST DAILY MEAN 340 Nov 8 340 Nov 8 1570 Sep 10 1996 LOWEST DAILY MEAN 0.76 Jun 20 1.1 Oct 26 0.20 Oct 4 1992 ANNUAL SEVEN-DAY MINIMUM 0.80 Jun 19 1.3 Oct 21 0.33 Oct 11 1992 MAXIMUM PEAK FLOW 1450 Dec 2 8890 Sep 10 1996 MAXIMUM PEAK STAGE 10.23 Dec 2 17.38 Sep 10 1996 ANNUAL RUNOFF (AC-FT) 4450 6120 6080 ANNUAL RUNOFF (CFSM) 1.22 1.68 1.67 ANNUAL RUNOFF (INCHES) 16.60 22.82 22.67 10 PERCENT EXCEEDS 11 13 14 50 PERCENT EXCEEDS 2.2 4.6 2.2 90 PERCENT EXCEEDS 1.1 1.8 0.86 e Estimated 165 RIO GRANDE DE MANATI BASIN 50030460 RIO OROCOVIS AT OROCOVIS, PR--Continued O N D 2001 J F M A M J J A S 2002 1 2 5 10 10 20 50 100 100 200 500 1000 DISCHARGE, IN CUBIC FEET PER SECOND 166 RIO GRANDE DE MANATI BASIN 50030700 RIO OROCOVIS NEAR OROCOVIS, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°14'20", long 66°22'58", at flat low bridge about 300 ft (91 m) northwest of Highway 568, 1.0 mi (1.6 km) north of Orocovis Plaza. DRAINAGE AREA.--10.1 mi2 (26.2 km2). PERIOD OF RECORD.--Water year 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 TURBID- FECAL FECAL SPECIF. PH, ITY, DIS- COD, COLI- STREP- HARD- INSTAN- CONDUC- WATER, WAT UNF SOLVED HIGH FORM, TOCOCCI NESS, TANEOUS TANCE, UNFLTRD TEMPER- LAB, DIS- OXYGEN, LEVEL, M-FC KF WATER, CALCIUM DIS- WAT UNF FIELD, ATURE, HACH SOLVED PERCENT WATER, 0.7U MF MF, UNFLTRD WATER, DATE TIME CHARGE, US/CM STD WATER, 2100AN OXYGEN, OF SAT- UNFLTRD COL/ COL/ MG/L AS FLTRD, CFS 25 DEGC UNITS DEG C NTU MG/L URATION MG/L 100 ML 100 ML CACO3 MG/L (00061) (00095) (00400) (00010) (99872) (00300) (00301) (00340) (31625) (31673) (00900) (00915) NOV 26... 0915 11 282 7.4 20.4 2.1 8.3 97 <10 2000 430 110 27.6 MAR 18... 1320 8.1 321 7.8 23.2 2.4 8.1 101 <10 230 E36 -- -- AUG 29... 0830 7.6 313 7.0 23.5 3.0 8.2 101 <10 5100 710 150 38.1 ANC, RESIDUE RESIDUE WAT UNF WATER, TOTAL MAGNES- POTAS- FIXED CHLOR- FLUOR- FLTRD, AT 105 IUM, SODIUM, SODIUM SIUM, END PT, SULFIDE SULFATE IDE, IDE, SILICA, SUM OF RESIDUE DEG. C, WATER, WATER, ADSORP- WATER, FIELD, WATER WATER, WATER, WATER, WATER, CONSTI- WATER, SUS- DATE FLTRD, FLTRD, TION FLTRD, MG/L AS UNFLTRD FLTRD, FLTRD, FLTRD, FLTRD, TUENTS FLTRD, PENDED, MG/L MG/L RATIO MG/L CACO3 MG/L MG/L MG/L MG/L MG/L MG/L TONS/D MG/L (00925) (00930) (00931) (00935) (00410) (00745) (00945) (00940) (00950) (00955) (70301) (70302) (00530) NOV 26... 10.9 12.2 .5 1.64 109 <1.0 6.8 15.9 <.1 32.7 173 5.34 <10 MAR 18... -- -- -- -- 133 -- -- -- -- -- -- -- <10 AUG 29... 13.0 13.2 .5 1.29 140 <.1 7.0 15.7 E.09 34.7 207 4.22 <10 NITRITE AMMONIA CHROM- + + BARIUM, BORON, IUM, COPPER, IRON, LEAD, NITRITE NITRATE AMMONIA ORG-N, PHOS- WATER, WATER, WATER, WATER, WATER, WATER, WATER, WATER WATER, WATER, PHORUS, ARSENIC UNFLTRD UNFLTRD CADMIUM UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD WATER, WATER RECOV- RECOV- WATER, RECOV- RECOV- RECOV- RECOV- DATE MG/L MG/L MG/L MG/L UNFLTRD UNFLTRD ERABLE, ERABLE, UNFLTRD ERABLE, ERABLE, ERABLE, ERABLE, AS N AS N AS N AS N MG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L (00615) (00630) (00610) (00625) (00665) (01002) (01007) (01022) (01027) (01034) (01042) (01045) (01051) NOV 26... <.01 1.10 .03 <.20 E.09 <2 45.4 30 <.1 <.8 <10 50 <1 MAR 18... .01 .700 .02 <.20 .06 -- -- -- -- -- -- -- -- AUG 29... <.01 .740 .01 .30 .13 <2 47.7 30 E.1 E.4 <10 130 <1 MANGAN- PHEN- ESE, MERCURY SILVER, ZINC, OLIC WATER, WATER, SELEN- WATER, WATER, COM- UNFLTRD UNFLTRD IUM, UNFLTRD UNFLTRD CYANIDE POUNDS, MBAS, RECOV- RECOV- WATER, RECOV- RECOV- WATER WATER, WATER, DATE ERABLE, ERABLE, UNFLTRD ERABLE, ERABLE, UNFLTRD UNFLTRD UNFLTRD UG/L UG/L UG/L UG/L UG/L MG/L UG/L MG/L (01055) (71900) (01147) (01077) (01092) (00720) (32730) (38260) NOV 26... 6.0 <.01 <2 <.3 <20 <.01 E107 <.05 MAR 18... -- -- -- -- -- -- -- -- AUG 29... 14.1 <.01 <2 <.3 E20 <.01 <16 <.05 < -- Less than E -- Estimated value 167 RIO GRANDE DE MANATI BASIN 50031200 RIO GRANDE DE MANATI NEAR MOROVIS, PR LOCATION.--Lat 18°17'45", long 66°24'47", Hydrologic Unit 21010001, on right bank, 0.1 mi (0.2 km) downstream from Quebrada Perchas, 0.8 mi (1.3 km) upstream from Río Sana Muerto, and 2.2 mi (3.5 km) south of Morovis. DRAINAGE AREA.--55.2 mi2 (143.0 km2). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--January 1965 to current year. GAGE.--Water-stage recorder and concrete control. Elevation of gage is 440 ft (134 m), from topographic map. February 2, 1966, to April 27, 1967, staff gage read twice daily. REMARKS.--Records fair except those for estimated daily discharges, which are poor. Public water-supply pumpage, about 1,000 ft (305 m) upstream from the station, influences low-flow discharges. Gage-height and precipitation satellite telemetry at station. Discharge, cubic feet per second WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 9.7 9.8 41 71 50 33 37 142 39 17 e109 39 2 8.5 10 200 67 45 35 34 126 38 17 e148 71 3 9.2 59 155 65 45 31 27 139 38 20 e62 317 4 9.7 26 121 63 63 31 25 121 40 22 e69 193 5 11 25 100 77 47 30 31 98 55 21 e65 76 6 16 57 73 163 46 27 70 108 69 22 e37 44 7 11 46 59 131 44 27 108 99 43 25 e27 31 8 10 4030 59 100 41 30 279 133 38 22 e31 27 9 17 e1300 50 83 41 31 186 87 37 21 e39 23 10 72 381 47 74 39 36 118 74 35 21 e67 22 11 44 158 47 69 39 45 81 68 35 21 e122 22 12 41 81 71 67 36 33 59 64 32 42 e207 21 13 20 75 72 65 35 30 47 61 29 65 e55 19 14 16 62 87 64 35 30 41 60 26 24 e44 28 15 57 62 72 62 33 25 44 56 25 23 e39 46 16 76 58 94 65 30 27 103 56 23 21 e26 103 17 40 59 171 60 29 24 118 54 26 21 e30 46 18 27 52 136 58 29 24 89 52 50 20 19 88 19 19 62 114 59 98 42 111 52 35 19 24 120 20 15 48 89 54 82 29 230 49 30 16 19 106 21 12 45 81 56 53 24 338 47 25 17 16 115 22 12 42 166 53 41 23 143 45 27 17 15 51 23 11 38 437 58 39 22 151 44 22 17 21 39 24 11 43 347 74 37 21 285 44 21 18 22 49 25 9.8 43 178 59 35 22 515 44 21 16 15 93 26 9.5 41 134 51 38 21 494 44 21 16 14 83 27 9.1 42 112 49 40 21 342 44 21 21 13 108 28 11 43 95 54 34 24 168 44 21 26 13 57 29 14 53 85 60 --- 58 129 41 19 31 14 111 30 11 57 78 53 --- 104 116 46 18 e24 21 61 31 9.8 --- 74 50 --- 43 --- 43 --- e24 58 --- TOTAL 649.3 7107.8 3645 2134 1224 1003 4519 2185 959 707 1461 2209 MEAN 20.9 237 118 68.8 43.7 32.4 151 70.5 32.0 22.8 47.1 73.6 MAX 76 4030 437 163 98 104 515 142 69 65 207 317 MIN 8.5 9.8 41 49 29 21 25 41 18 16 13 19 AC-FT 1290 14100 7230 4230 2430 1990 8960 4330 1900 1400 2900 4380 CFSM 0.38 4.29 2.13 1.25 0.79 0.59 2.73 1.28 0.58 0.41 0.85 1.33 IN. 0.44 4.79 2.46 1.44 0.82 0.68 3.05 1.47 0.65 0.48 0.98 1.49 STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1965 - 2002, BY WATER YEAR (WY) MEAN 145 148 111 81.3 63.2 60.9 100 147 58.9 43.6 52.1 108 MAX 1037 491 522 228 179 226 412 915 173 157 435 432 (WY) 1971 1971 1966 1997 1969 1972 1969 1985 1987 1979 1979 1996 MIN 20.9 11.4 8.65 10.4 15.3 12.7 8.80 15.7 6.75 5.54 9.70 6.87 (WY) 2002 1995 1995 1995 1994 1984 1995 1994 1994 1994 1984 1994 SUMMARY STATISTICS FOR 2001 CALENDAR YEAR FOR 2002 WATER YEAR WATER YEARS 1965 - 2002 ANNUAL TOTAL 18579.0 27803.1 ANNUAL MEAN 50.9 76.2 93.0 HIGHEST ANNUAL MEAN 248 1971 LOWEST ANNUAL MEAN 24.2 1994 HIGHEST DAILY MEAN 4030 Nov 8 4030 Nov 8 17100 May 18 1985 LOWEST DAILY MEAN 7.5 Jul 17 8.5 Oct 2 3.5 May 1 1995 ANNUAL SEVEN-DAY MINIMUM 8.6 Jul 11 10 Oct 22 4.0 Jul 22 1994 MAXIMUM PEAK FLOW 12800 Nov 8 48000 May 18 1985 MAXIMUM PEAK STAGE 10.37 Nov 8 17.89 May 18 1985 ANNUAL RUNOFF (AC-FT) 36850 55150 67360 ANNUAL RUNOFF (CFSM) 0.92 1.38 1.68 ANNUAL RUNOFF (INCHES) 12.52 18.74 22.89 10 PERCENT EXCEEDS 75 121 169 50 PERCENT EXCEEDS 21 44 48 90 PERCENT EXCEEDS 9.8 17 19 e Estimated 168 RIO GRANDE DE MANATI BASIN 50031200 RIO GRANDE DE MANATI NEAR MOROVIS, PR--Continued O N D 2001 J F M A M J J A S 2002 1 2 5 10 10 20 50 100 100 200 500 1000 1000 2000 5000 10,000 DISCHARGE, IN CUBIC FEET PER SECOND 169 RIO GRANDE DE MANATI BASIN 50031200 RIO GRANDE DE MANATI NEAR MOROVIS, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1968 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: October 2001 to September 2002. INSTRUMENTATION.--USDH-48 and automatic sediment sampler since 2001. REMARKS.--Sediment samples were collected by a local observer on a weekly basis. During high flow events sediment samples were collected with automatic sediment sampler. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATION: Maximum daily mean, 4,350 mg/L November 8, 2001; Minimum daily mean, 10 mg/L several days. SEDIMENT LOADS: Maximum daily mean, 60,000 tons (54,432 tonnes) November 8, 2001; Minimum daily mean, .59 ton (.54 tonne) March 26, 27, 2002. EXTREMES FOR CURRENT YEAR 2002.-- SEDIMENT CONCENTRATION: Maximum daily mean, 4,350 mg/L November 8, 2001; Minimum daily mean, 10 mg/L several days. SEDIMENT LOADS: Maximum daily mean, 60,000 tons (54,432 tonnes) November 8, 2001; Minimum daily mean, .59 ton (.54 tonne) March 26, 27, 2002 . WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 TURBID- FECAL FECAL SPECIF. PH, ITY, DIS- COD, COLI- STREP- HARD- INSTAN- CONDUC- WATER, WAT UNF SOLVED HIGH FORM, TOCOCCI NESS, TANEOUS TANCE, UNFLTRD TEMPER- LAB, DIS- OXYGEN, LEVEL, M-FC KF WATER, CALCIUM DIS- WAT UNF FIELD, ATURE, HACH SOLVED PERCENT WATER, 0.7U MF MF, UNFLTRD WATER, DATE TIME CHARGE, US/CM STD WATER, 2100AN OXYGEN, OF SAT- UNFLTRD COL/ COL/ MG/L AS FLTRD, CFS 25 DEGC UNITS DEG C NTU MG/L URATION MG/L 100 ML 100 ML CACO3 MG/L (00061) (00095) (00400) (00010) (99872) (00300) (00301) (00340) (31625) (31673) (00900) (00915) NOV 26... 1145 41 270 7.8 24.3 2.1 9.8 119 <10 270 E136 110 25.9 MAR 18... 1510 24 282 7.9 27.5 4.5 8.7 112 <10 E40 E30 -- -- AUG 29... 1025 14 274 7.6 27.7 4.2 10.1 129 <10 270 E80 120 29.4 ANC, RESIDUE RESIDUE WAT UNF WATER, TOTAL MAGNES- POTAS- FIXED CHLOR- FLUOR- FLTRD, AT 105 IUM, SODIUM, SODIUM SIUM, END PT, SULFIDE SULFATE IDE, IDE, SILICA, SUM OF RESIDUE DEG. C, WATER, WATER, ADSORP- WATER, FIELD, WATER WATER, WATER, WATER, WATER, CONSTI- WATER, SUS- DATE FLTRD, FLTRD, TION FLTRD, MG/L AS UNFLTRD FLTRD, FLTRD, FLTRD, FLTRD, TUENTS FLTRD, PENDED, MG/L MG/L RATIO MG/L CACO3 MG/L MG/L MG/L MG/L MG/L MG/L TONS/D MG/L (00925) (00930) (00931) (00935) (00410) (00745) (00945) (00940) (00950) (00955) (70301) (70302) (00530) NOV 26... 10.8 12.3 .5 2.48 106 <1.0 7.8 15.9 <.1 23.4 162 18.1 <10 MAR 18... -- -- -- -- 116 -- -- -- -- -- -- -- <10 AUG 29... 12.5 12.9 .5 1.54 123 <.1 6.8 15.4 E.10 28.8 181 6.94 <10 NITRITE AMMONIA CHROM- + + BARIUM, BORON, IUM, COPPER, IRON, LEAD, NITRITE NITRATE AMMONIA ORG-N, PHOS- WATER, WATER, WATER, WATER, WATER, WATER, WATER, WATER WATER, WATER, PHORUS, ARSENIC UNFLTRD UNFLTRD CADMIUM UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD WATER, WATER RECOV- RECOV- WATER, RECOV- RECOV- RECOV- RECOV- DATE MG/L MG/L MG/L MG/L UNFLTRD UNFLTRD ERABLE, ERABLE, UNFLTRD ERABLE, ERABLE, ERABLE, ERABLE, AS N AS N AS N AS N MG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L (00615) (00630) (00610) (00625) (00665) (01002) (01007) (01022) (01027) (01034) (01042) (01045) (01051) NOV 26... .01 .450 <.01 <.20 E.03 <2 45.3 30 <.1 <.8 <10 50 <1 MAR 18... <.01 .390 .02 <.20 .04 -- -- -- -- -- -- -- -- AUG 29... <.01 .130 .02 .30 .06 <2 47.8 30 <.1 <.8 <10 110 M MANGAN- PHEN- ESE, MERCURY SILVER, ZINC, OLIC WATER, WATER, SELEN- WATER, WATER, COM- UNFLTRD UNFLTRD IUM, UNFLTRD UNFLTRD CYANIDE POUNDS, MBAS, RECOV- RECOV- WATER, RECOV- RECOV- WATER WATER, WATER, DATE ERABLE, ERABLE, UNFLTRD ERABLE, ERABLE, UNFLTRD UNFLTRD UNFLTRD UG/L UG/L UG/L UG/L UG/L MG/L UG/L MG/L (01055) (71900) (01147) (01077) (01092) (00720) (32730) (38260) NOV 26... 10.9 <.01 E1 <.3 <20 <.01 E35 <.05 MAR 18... -- -- -- -- -- -- -- -- AUG 29... 12.8 <.01 <2 <.3 <20 <.01 <16 <.05 < -- Less than E -- Estimated value M -- Presence verified, not quantified 170 RIO GRANDE DE MANATI BASIN 50031200 RIO GRANDE DE MANATI NEAR MOROVIS, PR--Continued WATER-QUALITY RECORDS SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) OCTOBER NOVEMBER DECEMBER 1 9.7 51 1.3 9.8 56 1.5 41 224 25 2 8.5 50 1.2 10 55 1.6 200 838 1130 3 9.2 50 1.2 59 290 52 155 745 330 4 9.7 50 1.3 26 138 9.9 121 588 203 5 11 49 1.4 25 128 8.8 100 469 128 6 16 73 3.1 57 274 44 73 368 73 7 11 58 1.7 46 231 30 59 289 46 8 10 49 1.3 4030 4350 60000 59 268 43 9 17 86 4.1 e1300 e2870 e6830 50 221 30 10 72 334 127 381 1430 1550 47 220 28 11 44 207 26 158 743 328 47 232 29 12 41 205 26 81 330 73 71 337 68 13 20 116 6.4 75 304 62 72 347 68 14 16 82 3.6 62 299 50 87 415 99 15 57 270 63 62 295 49 72 357 70 16 76 361 80 58 289 45 94 437 137 17 40 200 22 59 270 43 171 805 380 18 27 144 11 52 249 35 136 641 235 19 19 103 5.4 62 236 40 114 536 166 20 15 84 3.4 48 230 30 89 431 104 21 12 78 2.6 45 224 27 81 379 84 22 12 72 2.3 42 219 25 166 750 392 23 11 66 2.0 38 215 22 437 1700 2850 24 11 60 1.8 43 211 25 347 1570 1570 25 9.8 54 1.4 43 208 24 178 862 419 26 9.5 54 1.4 41 204 22 134 651 236 27 9.1 55 1.4 42 200 23 112 535 162 28 11 56 1.7 43 196 23 95 419 107 29 14 57 2.1 53 257 39 85 304 69 30 11 58 1.7 57 297 47 78 188 40 31 9.8 57 1.5 --- --- --- 74 73 15 TOTAL 649.3 --- 410.3 7107.8 --- 69559.8 3645 --- 9336 171 RIO GRANDE DE MANATI BASIN 50031200 RIO GRANDE DE MANATI NEAR MOROVIS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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 FEBRUARY MARCH 1 71 15 2.8 50 49 6.6 33 18 1.6 2 67 14 2.6 45 48 5.9 35 19 1.8 3 65 14 2.4 45 48 5.8 31 19 1.6 4 63 13 2.3 63 47 8.0 31 19 1.6 5 77 156 41 47 47 5.9 30 20 1.6 6 163 773 345 46 46 5.7 27 20 1.4 7 131 630 226 44 46 5.4 27 19 1.4 8 100 473 127 41 45 5.0 30 19 1.5 9 83 358 80 41 45 4.9 31 18 1.5 10 74 244 49 39 44 4.7 36 97 14 11 69 129 24 39 44 4.7 45 85 13 12 67 29 5.3 36 43 4.2 33 33 2.9 13 65 14 2.5 35 43 4.1 30 30 2.3 14 64 14 2.4 35 42 4.0 30 26 2.1 15 62 24 4.1 33 42 3.7 25 23 1.6 16 65 40 7.0 30 41 3.4 27 20 1.4 17 60 36 5.9 29 41 3.2 24 16 1.1 18 58 32 4.9 29 40 3.1 24 13 0.85 19 59 27 4.3 98 427 151 42 166 22 20 54 22 3.2 82 234 65 29 32 2.8 21 56 17 2.5 53 243 35 24 11 0.72 22 53 12 1.7 41 189 21 23 11 0.69 23 58 10 1.6 39 136 15 22 11 0.65 24 74 22 4.5 37 90 9.0 21 11 0.60 25 59 26 4.1 35 43 4.1 22 10 0.63 26 51 25 3.4 38 15 1.6 21 10 0.59 27 49 23 3.1 40 14 1.6 21 10 0.59 28 54 23 3.3 34 16 1.5 24 10 0.67 29 60 26 4.2 --- --- --- 58 136 83 30 53 31 4.4 --- --- --- 104 475 146 31 50 39 5.3 --- --- --- 43 228 27 TOTAL 2134 --- 979.8 1224 --- 393.1 1003 --- 339.19 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) APRIL MAY JUNE 1 37 168 17 142 674 292 39 166 18 2 34 155 14 126 594 206 38 157 16 3 27 141 10 139 656 252 38 147 15 4 25 128 8.6 121 564 187 40 139 15 5 31 157 14 98 467 124 55 201 33 6 70 403 137 108 501 147 69 336 66 7 108 543 193 99 473 136 43 213 25 8 279 1250 1070 133 632 241 38 174 18 9 186 853 432 87 414 97 37 167 17 10 118 555 182 74 364 73 35 202 19 11 81 381 83 68 340 63 35 203 19 12 59 293 47 64 323 56 32 204 18 13 47 254 32 61 306 51 29 206 16 14 41 222 25 60 296 48 26 208 15 15 44 220 26 56 283 43 25 240 17 16 103 430 122 56 277 42 23 282 18 17 118 557 182 54 272 40 26 278 19 18 89 433 126 52 266 38 50 201 27 19 111 532 173 52 261 36 35 174 17 20 230 1050 1090 49 255 33 30 145 12 21 338 1530 1620 47 249 32 25 119 8.2 22 143 665 261 45 244 30 27 123 8.9 23 151 753 759 44 238 29 22 136 8.1 24 285 1140 1750 44 233 28 21 149 8.7 25 515 1850 3630 44 227 27 21 165 9.3 26 494 1770 3280 44 221 26 21 183 10 27 342 1530 1730 44 215 25 21 201 12 28 168 813 372 44 206 24 21 217 12 29 129 601 211 41 196 22 19 189 9.8 30 116 556 178 46 186 23 18 145 7.2 31 --- --- --- 43 176 20 --- --- --- TOTAL 4519 --- 17774.6 2185 --- 2491 959 --- 514.2 172 RIO GRANDE DE MANATI BASIN 50031200 RIO GRANDE DE MANATI NEAR MOROVIS, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) JULY AUGUST SEPTEMBER 1 17 104 4.9 e109 e190 e34 39 202 22 2 17 109 5.2 e148 e364 e82 71 333 157 3 20 126 6.8 e62 e227 e32 317 1240 1730 4 22 143 8.5 e69 e213 e28 193 875 547 5 21 160 9.1 e65 e142 e9.8 76 343 71 6 22 177 11 e37 e131 e9.1 44 225 27 7 25 194 13 e27 e121 e6.6 31 164 14 8 22 199 12 e31 e112 e6.3 27 137 9.9 9 21 172 9.8 e39 e128 e8.8 23 126 7.9 10 21 144 8.5 e67 e109 e6.1 22 116 6.9 11 21 116 6.5 e122 e149 e13 22 106 6.5 12 42 185 38 e207 e219 e29 21 102 5.7 13 65 309 67 e55 e122 e7.9 19 97 4.9 14 24 130 8.6 e44 e110 e7.6 28 142 14 15 23 123 7.6 e39 e106 e8.0 46 238 31 16 21 135 7.6 e26 e103 e5.8 103 482 153 17 21 151 8.9 e30 e102 e7.3 46 234 31 18 20 168 8.9 19 102 5.3 88 424 186 19 19 186 9.4 24 101 6.5 120 564 192 20 16 216 9.3 19 96 4.9 106 507 189 21 17 249 11 16 91 4.0 115 548 189 22 17 280 13 15 86 3.6 51 256 36 23 17 268 13 21 82 4.5 39 195 21 24 18 240 12 22 79 4.7 49 238 36 25 16 212 9.3 15 75 3.2 93 445 116 26 16 184 7.9 14 72 2.7 83 399 106 27 21 156 8.8 13 69 2.5 108 509 158 28 26 166 12 13 70 2.5 57 290 45 29 31 168 14 14 72 2.8 111 518 167 30 e24 e101 e5.3 21 109 7.6 61 289 48 31 e24 e89 e3.9 58 286 47 --- --- --- TOTAL 707 --- 370.8 1461 --- 403.1 2209 --- 4327.8 YEAR 27803.1 106899.69 e Estimated WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 SILT AND CLAY PERCENT OF SUSPENDED SEDIMENT Sus- Suspnd. pended Sus- sedi- Instan- sedi- pended ment, taneous ment sedi- sieve dis- concen- ment diametr Date Time charge, tration load, percent cfs mg/L tons/d <.063mm (00061) (80154) (80155) (70331) APR 24... 1855 1150 6870 21300 96 26... 2255 1580 5470 23300 93 173 RIO GRANDE DE MANATI BASIN 50032290 LAGO EL GUINEO AT DAMSITE NEAR VILLALBA, PR LOCATION.--Lat 18°09'41", long 66°31'36", Hydrologic Unit 21010001, at damsite on Río Toro Negro, 3.0 mi (4.8 km) northwest from Villalba Plaza and 1.9 mi (3.1 km) northeast of Cerro Maravillas. The reservoir itself fixes the territorial limits between the municipality of Ciales and Orocovis. DRAINAGE AREA.--1.64 mi2 (4.25 km2). ELEVATION RECORDS PERIOD OF RECORD.--May 1988 to current year. Prior to October 1994, published as Lago El Guineo at Damsite. GAGE.--Water-stage recorder. Datum of gage is mean sea level. REMARKS.--Lago El Guineo was completed in 1931. It provides a maximum storage of approximately 2,180 acre-ft (2.688 hm3) for power and irrigation. Waters are discharged through an outlet power tunnel into the Río Toro Negro and conveyed to the head water works of Toro Negro Hydroelectric Plant No. 2, for energy generation at Toro Negro Hydroelectric plant No. 1, and are discharged into the Guayabal Reservoir to be later used for irrigation at South Coast Irrigation System. The dam is rockfill with a vertical concrete corewall, rock toes, and riprap facing of upstream slope, with a total length of 565 ft (172 m), a maximum structural height of 125 ft (38 m) to top of corewall. At a maximum reservoir water surface elevation the uncontrolled morning-glory tunnel spillway crest has an elevation of 2,960 ft (902 m) above mean sea level and a design capacity of 7,000 ft3/s. 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 2,964.40 ft (905.55 m), September 22, 1998; minimun elevation, 2,919.79 ft (899.95 m), May 27, 1988. EXTREMES OBSERVED FOR CURRENT YEAR.--Maximum elevation, 2,961.84 ft (902.77 m), April 25; minimun elevation, 2,948.63 ft (896.74 m), October 10. 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 2,872 0 2,950 1,308 2,919 361 2,961 1,852 2,925 491 2,966 2,180 2,943 1,029 Elevation above NGVD 1929, feet WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 DAILY OBSERVATION AT 2400 HOURS DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 2953.59 2956.30 2959.17 2960.79 2955.75 2954.45 2956.15 2960.74 2960.71 2960.68 2960.71 2960.71 2 2953.35 2957.72 2959.53 2960.48 2955.83 2954.49 2956.05 2960.80 2960.73 2960.67 2960.67 2960.71 3 2953.13 2958.08 2960.01 2960.22 2955.96 2954.54 2956.00 2960.73 2960.79 2960.68 2960.67 2960.76 4 2952.73 2958.44 2959.85 2959.81 2955.43 2954.57 2955.94 2960.73 2960.81 2960.67 2960.24 2960.60 5 2952.37 2958.75 2960.02 2959.98 2954.60 2954.04 2956.43 2960.73 2960.91 2960.67 2960.34 2960.51 6 2951.64 2959.42 2960.17 2960.13 2954.67 2953.71 2956.61 2960.71 2960.84 2960.73 2960.41 2960.40 7 2950.78 2959.42 2960.30 2960.25 2954.73 2953.44 2956.75 2960.73 2960.76 2960.67 2960.50 2960.47 8 2949.84 2960.86 2960.46 2959.93 2954.80 2953.51 2956.78 2960.70 2960.76 2960.67 2960.32 2960.53 9 2949.19 2960.71 2960.58 2959.92 2954.87 2953.55 2956.76 2960.69 2960.74 2960.68 2959.97 2960.39 10 2951.85 2960.74 2960.33 2959.93 2954.93 2953.60 2956.66 2960.69 2960.56 2960.66 2960.06 2960.28 11 2951.61 2960.73 2960.13 2959.54 2954.98 2954.09 2956.57 2960.70 2960.71 2960.66 2960.78 2960.14 12 2951.87 2960.72 2959.89 2959.64 2954.44 2953.60 2956.53 2960.70 2960.51 2960.66 2960.51 2960.20 13 2951.39 2960.63 2959.63 2959.75 2953.78 2953.44 2956.62 2960.65 2960.43 2960.66 2960.22 2960.24 14 2950.89 2960.49 2959.35 2959.85 2953.84 2953.28 2956.70 2960.65 2960.57 2960.70 2959.92 2960.29 15 2950.90 2960.37 2959.47 2959.42 2953.89 2953.16 2956.85 2960.65 2960.70 2960.66 2959.60 2960.73 16 2951.12 2960.21 2959.68 2959.09 2953.95 2953.81 2956.90 2960.65 2960.70 2960.66 2959.29 2960.62 17 2951.53 2960.47 2959.93 2958.77 2954.00 2953.93 2956.89 2960.63 2960.35 2960.66 2959.34 2960.49 18 2951.83 2960.68 2960.02 2958.47 2954.06 2953.83 2959.14 2960.68 2960.07 2960.66 2959.39 2960.42 19 2951.98 2960.72 2959.98 2958.56 2954.24 2953.61 2959.35 2960.67 2960.28 2960.66 2959.41 2960.28 20 2952.19 2960.72 2960.13 2958.65 2954.28 2953.41 2960.58 2960.67 2960.37 2960.66 2959.45 2960.12 21 2952.40 2960.73 2960.83 2958.74 2954.33 2953.29 2960.77 2960.56 2960.41 2960.66 2959.47 2960.19 22 2952.59 2960.73 2960.75 2958.82 2954.14 2953.33 2960.72 2960.25 2960.53 2960.68 2959.61 2959.89 23 2952.78 2960.74 2960.75 2958.91 2954.18 2953.37 2960.80 2960.26 2960.68 2960.66 2959.79 2959.67 24 2952.97 2960.73 2960.74 2958.56 2954.23 2953.41 2960.80 2959.84 2960.69 2960.65 2960.03 2959.63 25 2953.12 2960.73 2960.75 2958.26 2954.27 2952.77 2960.86 2959.93 2960.69 2960.66 2960.15 2959.52 26 2953.43 2960.00 2960.72 2958.34 2954.32 2952.54 2960.81 2960.02 2960.69 2960.66 2960.21 2959.32 27 2953.76 2959.65 2960.47 2958.41 2954.36 2952.34 2960.79 2960.16 2960.69 2960.67 2960.25 2959.13 28 2954.67 2959.44 2960.44 2957.99 2954.40 2952.39 2960.75 2960.26 2960.68 2960.67 2960.31 2959.22 29 2955.59 2959.26 2960.58 2957.60 --- 2955.59 2960.85 2960.61 2960.68 2960.66 2960.35 2958.96 30 2955.88 2959.02 2960.73 2956.99 --- 2955.98 2960.71 2960.84 2960.69 2960.66 2960.48 2958.75 31 2956.10 --- 2960.78 2956.39 --- 2956.23 --- 2960.73 --- 2960.66 2960.66 --- MAX 2956.10 2960.86 2960.83 2960.79 2955.96 2956.23 2960.86 2960.84 2960.91 2960.73 2960.78 2960.76 MIN 2949.19 2956.30 2959.17 2956.39 2953.78 2952.34 2955.94 2959.84 2960.07 2960.65 2959.29 2958.75 174 RIO GRANDE DE MANATI BASIN 50032290 LAGO EL GUINEO AT DAMSITE NEAR VILLALBA, PR--Continued O N D 2001 J F M A M J J A S 2002 2948 2950 2952 2954 2956 2958 2960 2962 ELEVATION, IN FEET 175 RIO GRANDE DE MANATI BASIN 50032590 LAGO DE MATRULLAS AT DAMSITE NEAR OROCOVIS, PR LOCATION.--Lat 18°12'46", long 66°28'50", Hydrologic Unit 21010001, in shelter house at damsite, and 5.8 mi (9.3 km) southwest of Orocovis. DRAINAGE AREA.--4.46 mi2 (11.6 km2). ELEVATION RECORDS PERIOD OF RECORD.--May 1988 to current year. Prior to October 1994, published as Lago de Matrullas at Damsite. 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 acre-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 PREPA. 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 Díaz Canal. Gage-height and precipitation satellite telemetry at station. EXTREMES OBSERVED FOR PERIOD OF RECORD.--Maximum elevation 2,419.90 ft (737.58 m), September 10, 1996; minimum elevation, 2,375.55 ft (724.06 m), September 24 and 25, 1994. EXTREMES OBSERVED FOR CURRENT YEAR.--Maximum elevation, 2,416.43 ft (736.54 m); November 15; minimum elevation, 2,404.72 ft (732.95 m) October 30. 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 2,338 2 2,399 1,845 2,360 302 2,420 3,331 Elevation above NGVD 1929, feet WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 DAILY OBSERVATION AT 2400 HOURS DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 2409.31 2405.04 2415.13 2415.24 2414.55 2413.51 2413.94 2415.41 2415.25 2415.37 2414.63 2414.35 2 2409.04 2405.56 2415.16 2415.23 2414.56 2413.47 2413.99 2415.41 2415.25 2415.37 2414.60 2414.39 3 2409.84 A 2415.16 2415.00 2414.57 2413.44 2414.05 2415.41 2415.25 2415.34 2414.58 2414.42 4 2408.58 2405.39 2415.17 2415.19 2414.57 2413.38 2414.11 2415.41 2415.28 2415.32 2414.56 2414.44 5 2408.38 2405.97 2415.17 2415.27 2414.55 2413.38 2414.19 2415.41 2415.29 2415.30 2414.53 2414.45 6 2408.05 2406.84 2415.18 2415.25 2414.54 2413.40 2414.25 2415.41 2415.30 2415.28 2414.50 2414.47 7 2407.70 A 2415.17 2415.24 2414.49 2413.43 2414.32 2415.41 2415.29 2415.26 2414.47 2414.50 8 2407.36 A 2415.19 2415.24 2414.44 2413.45 2414.39 2415.38 2415.30 2415.21 2414.44 2414.53 9 2407.06 A 2415.19 2415.09 2414.40 2413.49 2414.46 2415.36 2415.31 2415.20 2414.41 2414.55 10 2407.32 2415.41 2415.18 2415.00 2414.36 2413.54 2414.52 2415.36 2415.30 2415.17 2414.40 2414.56 11 2407.33 2415.45 2415.18 2414.93 2414.32 2413.60 2414.58 2415.36 2415.31 2415.16 2414.39 2414.59 12 2407.58 2415.50 2415.18 2415.12 2414.26 2413.63 2414.64 2415.35 2415.30 2415.12 2414.35 2414.61 13 2407.34 2415.50 2415.18 2415.23 2414.22 2413.66 2414.69 2415.35 2415.31 2415.10 2414.31 2414.63 14 2407.05 2415.56 2415.19 2415.23 2414.19 2413.68 2414.76 2415.35 2415.32 2415.08 2414.28 2414.65 15 2406.94 A 2415.19 2415.06 2414.12 2413.70 2414.81 2415.35 2415.32 2415.05 2414.23 2414.70 16 2406.79 A 2415.20 2414.98 2414.08 2413.75 2414.87 2415.34 2415.32 2415.02 2414.21 2414.72 17 2406.72 A 2415.18 2414.91 2414.05 2413.78 2414.92 2415.34 2415.31 2415.01 2414.20 2414.75 18 2406.54 A 2415.19 2414.76 2413.99 2413.81 2415.00 2415.32 2415.33 2414.99 2414.18 2414.81 19 A A 2415.18 2414.75 2413.98 2413.83 2415.06 2415.32 2415.33 2414.95 2414.15 2414.72 20 2406.38 A 2415.19 2414.88 2413.94 2413.83 2415.14 2415.31 2415.33 2414.91 2414.11 2414.54 21 A A 2415.20 2414.97 2413.89 2413.80 2415.17 2415.31 2415.34 2414.90 2414.07 2414.39 22 A A 2415.20 2414.81 2413.84 2413.77 2415.24 2415.29 2415.34 2414.87 2414.06 2414.30 23 A 2415.31 2415.21 2414.67 2413.80 2413.73 2415.31 2415.29 2415.36 2414.85 2414.08 2414.91 24 A A 2415.22 2414.58 2413.78 2413.71 2415.37 2415.28 2415.36 2414.81 2414.12 2414.92 25 2405.75 A 2415.21 2414.42 2413.72 2413.68 2415.42 2415.30 2415.35 2414.79 2414.15 2414.92 26 2405.54 A 2415.20 2414.57 2413.68 2413.64 2415.42 2415.29 2415.36 2414.76 2414.19 2414.78 27 2405.15 A 2415.09 2414.57 2413.62 2413.60 2415.41 2415.28 2415.36 2414.75 2414.20 2414.90 28 2404.87 A 2415.03 2414.58 2413.56 2413.64 2415.41 2415.27 2415.36 2414.72 2414.23 2414.92 29 A A 2415.23 2414.57 --- 2413.77 2415.42 2415.28 2415.36 2414.69 2414.25 2414.86 30 A 2415.14 2415.24 2414.56 --- 2413.83 2415.42 2415.27 2415.36 2414.68 2414.27 2414.65 31 2404.88 --- 2415.24 2414.55 --- 2413.89 --- 2415.25 --- 2414.65 2414.29 --- MAX --- --- 2415.24 2415.27 2414.57 2413.89 2415.42 2415.41 2415.36 2415.37 2414.63 2414.92 MIN --- --- 2415.03 2414.42 2413.56 2413.38 2413.94 2415.25 2415.25 2414.65 2414.06 2414.30 A No gage-height record 176 RIO GRANDE DE MANATI BASIN 50032590 LAGO DE MATRULLAS AT DAMSITE NEAR OROCOVIS, PR--Continued O N D 2001 J F M A M J J A S 2002 2404 2406 2408 2410 2412 2414 2416 ELEVATION, IN FEET Gap indicates missing record 177 RIO GRANDE 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 mi2 (43.3 km2). 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. Gage-height and precipitation satellite telemetry at station. Discharge, cubic feet per second WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 11 8.8 15 23 14 12 23 47 21 10 62 11 2 11 71 285 22 14 12 17 52 22 11 21 60 3 13 45 145 21 14 12 13 47 27 10 21 87 4 13 17 100 21 16 11 12 38 33 10 16 48 5 12 42 58 29 14 11 40 33 167 10 14 22 6 13 72 37 45 14 11 47 30 91 11 12 15 7 10 55 29 30 13 11 34 36 43 12 12 12 8 10 1150 24 25 13 12 159 33 28 10 12 11 9 13 308 21 22 13 11 131 30 22 9.9 13 10 10 33 125 20 21 12 12 61 26 20 9.7 14 9.7 11 24 70 19 20 12 23 37 24 18 9.5 32 9.4 12 17 46 20 19 12 20 27 24 17 12 27 9.1 13 12 34 18 19 12 12 21 22 16 12 15 8.7 14 11 32 20 18 12 11 17 22 16 9.4 13 10 15 12 67 17 18 12 11 18 21 15 11 12 14 16 16 56 30 18 12 11 24 21 14 9.4 14 35 17 16 39 29 17 11 10 19 20 17 9.1 12 14 18 12 29 25 17 22 10 152 19 18 8.9 12 42 19 10 25 26 16 92 13 130 20 15 8.6 13 28 20 9.3 21 21 16 44 10 259 18 13 8.3 11 80 21 8.8 19 110 16 19 9.8 291 17 13 8.4 11 61 22 8.5 17 95 17 15 9.6 111 17 13 8.4 12 22 23 8.3 16 138 16 13 9.2 218 18 12 8.6 11 16 24 8.1 17 165 21 13 9.1 335 18 12 8.6 11 28 25 7.7 17 84 16 12 9.0 525 17 12 8.1 10 34 26 7.5 15 52 15 15 8.9 399 17 11 7.8 9.7 23 27 8.0 15 39 15 13 9.2 221 19 11 8.4 9.1 18 28 22 15 32 16 12 15 109 18 11 e8.9 9.2 16 29 15 28 28 15 --- 130 74 19 11 8.5 12 23 30 9.5 20 26 15 --- 68 58 43 11 7.9 14 16 31 8.4 --- 25 15 --- 27 --- 28 --- 8.5 13 --- TOTAL 390.1 2491.8 1753 614 490 550.8 3582 814 750 293.9 480.0 792.9 MEAN 12.6 83.1 56.5 19.8 17.5 17.8 119 26.3 25.0 9.48 15.5 26.4 MAX 33 1150 285 45 92 130 525 52 167 12 62 87 MIN 7.5 8.8 15 15 11 8.9 12 17 11 7.8 9.1 8.7 AC-FT 774 4940 3480 1220 972 1090 7100 1610 1490 583 952 1570 CFSM 0.75 4.97 3.39 1.19 1.05 1.06 7.15 1.57 1.50 0.57 0.93 1.58 IN. 0.87 5.55 3.90 1.37 1.09 1.23 7.98 1.81 1.67 0.65 1.07 1.77 STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1969 - 2002, BY WATER YEAR (WY) MEAN 80.7 58.0 30.4 21.6 17.0 15.2 29.7 48.7 20.4 15.2 21.3 109 MAX 392 205 108 83.4 43.5 59.9 119 179 78.6 104 152 1104 (WY) 1971 1971 1971 1992 1998 1972 2002 1981 1979 1979 1979 1996 MIN 12.6 7.12 4.29 3.66 5.70 4.18 4.92 4.24 3.59 3.22 3.97 3.55 (WY) 2002 1995 1995 1995 1994 1994 1995 1994 1994 1994 1994 1994 SUMMARY STATISTICS FOR 2001 CALENDAR YEAR FOR 2002 WATER YEAR WATER YEARS 1969 - 2002 ANNUAL TOTAL 10687.1 13002.5 ANNUAL MEAN 29.3 35.6 39.0 HIGHEST ANNUAL MEAN 117 1996 LOWEST ANNUAL MEAN 6.56 1994 HIGHEST DAILY MEAN 1150 Nov 8 1150 Nov 8 19500 Sep 10 1996 LOWEST DAILY MEAN 6.7 Aug 13 7.5 Oct 26 2.8 Jul 23 1994 ANNUAL SEVEN-DAY MINIMUM 7.0 Aug 10 8.1 Oct 21 2.8 Jul 23 1994 MAXIMUM PEAK FLOW 2560 Apr 25 28200 Sep 22 1998 MAXIMUM PEAK STAGE 12.61 Apr 25 25.93 Sep 22 1998 INSTANTANEOUS LOW FLOW 7.1 Oct 25 2.6 Jul 26 1994 ANNUAL RUNOFF (AC-FT) 21200 25790 28250 ANNUAL RUNOFF (CFSM) 1.75 2.13 2.33 ANNUAL RUNOFF (INCHES) 23.81 28.96 31.72 10 PERCENT EXCEEDS 59 64 68 50 PERCENT EXCEEDS 12 16 14 90 PERCENT EXCEEDS 8.1 9.4 5.7 e Estimated 178 RIO GRANDE DE MANATI BASIN 50034000 RIO BAUTA NEAR OROCOVIS, PR--Continued O N D 2001 J F M A M J J A S 2002 1 2 5 10 10 20 50 100 100 200 500 1000 1000 2000 5000 10,000 DISCHARGE, IN CUBIC FEET PER SECOND 179 RIO GRANDE DE MANATI BASIN 50035000 RIO GRANDE 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 Highway 145 bridge, 0.8 mi (1.3 km) downstream from Quebrada Saliente, 0.9 mi (1.4 km) upstream from Quebrada Cojo Valés, and 1.2 mi (1.9 km) southeast of Ciales. DRAINAGE AREA.--128 mi2 (332 km2), excludes 6.0 mi2 (15.5 km2), the runoff from which is diverted through El Guineo and 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, 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 Río Grande de Manatí at Highway 145 at Ciales at site 1.6 mi (2.6 km) downstream, drainage area 132 mi2 (342 km2). GAGE.--Water-stage recorder. Elevation of gage is 140 ft (43 m), from topographic map. Prior to April 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. Since October 1, 1997, 2.0 ft (0.6 m) were added to gage 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 2001 TO SEPTEMBER 2002 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 e47 e50 118 164 113 83 164 442 141 93 154 102 2 e41 e52 362 158 105 86 122 472 140 93 186 319 3 e43 e172 431 148 104 82 104 403 188 92 115 1090 4 e45 e75 340 143 126 81 84 316 191 91 122 595 5 e51 e72 300 175 108 80 96 267 542 90 118 223 6 e72 e166 198 340 105 77 261 255 323 94 95 138 7 e53 e133 161 278 104 75 247 224 186 104 85 113 8 e47 e11600 149 209 97 80 697 284 144 92 89 103 9 e79 e3800 134 181 95 83 526 210 138 90 96 96 10 e130 e1100 129 161 96 86 303 194 129 90 120 94 11 e110 426 125 149 94 122 200 185 117 93 164 91 12 e100 302 157 142 90 167 157 183 113 136 234 88 13 e58 241 160 137 89 90 129 177 110 137 109 85 14 e47 206 172 136 88 83 117 168 107 94 100 102 15 e120 211 156 136 87 76 118 166 104 94 97 123 16 e140 203 224 132 84 76 186 164 107 89 85 193 17 e100 176 401 129 82 142 212 161 110 89 89 124 18 e80 167 288 124 82 81 455 155 128 87 82 256 19 e65 170 239 122 253 92 531 156 120 85 83 360 20 e60 150 187 117 268 81 829 151 109 82 82 263 21 e55 137 291 119 135 e83 1360 141 102 82 77 296 22 e52 129 418 117 104 e81 527 137 104 84 76 138 23 e52 128 646 126 94 e77 965 135 102 85 91 115 24 e50 143 806 150 89 e73 1360 132 101 84 88 116 25 e49 140 425 131 85 e75 2540 131 101 81 85 164 26 e47 129 291 115 91 e73 2280 133 99 79 78 182 27 e45 122 232 114 99 e73 1460 135 102 85 75 194 28 e47 123 200 115 85 e83 682 138 100 92 73 128 29 e70 145 180 129 --- 319 716 129 96 98 76 154 30 e60 156 172 118 --- 351 616 206 95 84 91 118 31 e52 --- 171 112 --- 189 --- 222 --- 84 119 --- TOTAL 2067 20824 8263 4627 3052 3300 18044 6372 4249 2853 3234 6163 MEAN 66.7 694 267 149 109 106 601 206 142 92.0 104 205 MAX 140 11600 806 340 268 351 2540 472 542 137 234 1090 MIN 41 50 118 112 82 73 84 129 95 79 73 85 AC-FT 4100 41300 16390 9180 6050 6550 35790 12640 8430 5660 6410 12220 CFSM 0.52 5.42 2.08 1.17 0.85 0.83 4.70 1.61 1.11 0.72 0.82 1.60 IN. 0.60 6.05 2.40 1.34 0.89 0.96 5.24 1.85 1.23 0.83 0.94 1.79 e Estimated 180 RIO GRANDE DE MANATI BASIN 50035000 RIO GRANDE DE MANATI AT CIALES, PR--Continued STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1946 - 2002, BY WATER YEAR (WY) MEAN 417 360 264 193 164 133 252 394 155 103 147 310 MAX 2422 1029 1296 679 1393 477 1174 2293 512 438 1212 1295 (WY) 1971 2000 1966 1952 1950 1969 1969 1985 1999 1979 1979 1996 MIN 66.7 34.7 29.7 26.2 41.6 29.7 28.5 29.6 17.8 14.1 27.0 23.9 (WY) 2002 1995 1995 1995 1957 1994 1984 1994 1994 1994 1994 1994 SUMMARY STATISTICS FOR 2001 CALENDAR YEAR FOR 2002 WATER YEAR WATER YEARS 1946 - 2002 ANNUAL TOTAL 55384 83048 ANNUAL MEAN 152 228 242 HIGHEST ANNUAL MEAN 520 1971 LOWEST ANNUAL MEAN 47.3 1994 HIGHEST DAILY MEAN 11600 Nov 8 11600 Nov 8 42700 May 18 1985 LOWEST DAILY MEAN 36 Aug 14 41 Oct 2 8.5 Jul 28 1994 ANNUAL SEVEN-DAY MINIMUM 37 Aug 11 49 Oct 22 9.5 Jul 24 1994 MAXIMUM PEAK FLOW Unknown Nov 8 128000 Sep 10 1996 MAXIMUM PEAK STAGE Unknown Nov 8 25.20 Sep 10 1996 INSTANTANEOUS LOW FLOW 8.5 Jul 27 1994 ANNUAL RUNOFF (AC-FT) 109900 164700 175200 ANNUAL RUNOFF (CFSM) 1.19 1.78 1.89 ANNUAL RUNOFF (INCHES) 16.10 24.14 25.67 10 PERCENT EXCEEDS 227 330 443 50 PERCENT EXCEEDS 73 122 115 90 PERCENT EXCEEDS 43 76 50 O N D 2001 J F M A M J J A S 2002 10 20 50 100 100 200 500 1000 1000 2000 5000 10,000 10,000 20,000 50,000 100,000 DISCHARGE, IN CUBIC FEET PER SECOND 181 RIO GRANDE DE MANATI BASIN 50035000 RIO GRANDE DE MANATI AT CIALES, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--September 1946 to September 1953, May 1956 to December 1957 (unpublished, available in files of Caribbean District Office), 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 Río Grande de Manatí at Highway 145 at Ciales at site 1.6 mi (2.6 km) downstream, drainage area 132 mi2 (342 km2). PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: December 2001 to September 2002. INSTRUMENTATION.--USDH-48 sediment sampler and automatic sediment sampler since 2001. REMARKS.--Sediment samples were collected by a local observer on a weekly basis. During high flow events sediment samples were collected with automatic sediment sampler. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATION: Maximum daily mean, 2,890 mg/L April 25, 2002; Minimum daily mean, 1 mg/L several days. SEDIMENT LOADS: Maximum daily mean, 35,300 tons (32,024 tonnes) April 25, 2002; Minimum daily mean, .26 ton (.24 tonne) July 16, 2002. EXTREMES FOR CURRENT YEAR 2002.-- SEDIMENT CONCENTRATION: Maximum daily mean, 2,890 mg/L April 25, 2002; Minimum daily mean, 1 mg/L several days. SEDIMENT LOADS: Maximum daily mean, 35,300 tons (32,024 tonnes) April 25, 2002; Minimum daily mean, .26 ton (.24 tonne) July 16, 2002. SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) OCTOBER NOVEMBER DECEMBER 1 e47 --- --- e50 --- --- 118 35 11 2 e41 --- --- e52 --- --- 362 359 748 3 e43 --- --- e172 --- --- 431 431 562 4 e45 --- --- e75 --- --- 340 301 300 5 e51 --- --- e72 --- --- 300 224 193 6 e72 --- --- e166 --- --- 198 111 60 7 e53 --- --- e133 --- --- 161 65 28 8 e47 --- --- e11600 --- --- 149 59 24 9 e79 --- --- e3800 --- --- 134 53 19 10 e207 --- --- e1100 --- --- 129 47 16 11 e128 --- --- 426 --- --- 125 41 14 12 e118 --- --- 302 --- --- 157 64 29 13 e58 --- --- 241 --- --- 160 76 33 14 e47 --- --- 206 --- --- 172 74 34 15 e166 --- --- 211 --- --- 156 69 29 16 e221 --- --- 203 --- --- 224 182 172 17 e116 --- --- 176 --- --- 401 401 444 18 e80 --- --- 167 --- --- 288 201 159 19 e65 --- --- 170 --- --- 239 130 84 20 e60 --- --- 150 --- --- 187 94 48 21 e55 --- --- 137 --- --- 291 243 305 22 e52 --- --- 129 --- --- 418 415 492 23 e52 --- --- 128 --- --- 646 645 1400 24 e50 --- --- 143 --- --- 806 827 1850 25 e49 --- --- 140 --- --- 425 452 532 26 e47 --- --- 129 --- --- 291 250 200 27 e45 --- --- 122 --- --- 232 135 85 28 e47 --- --- 123 --- --- 200 111 60 29 e70 --- --- 145 --- --- 180 88 43 30 e60 --- --- 156 --- --- 172 70 32 31 e52 --- --- --- --- --- 171 66 30 TOTAL 2323 --- --- 20824 --- --- 8263 --- 8036 182 RIO GRANDE DE MANATI BASIN 50035000 RIO GRANDE DE MANATI AT CIALES, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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 FEBRUARY MARCH 1 164 62 27 113 12 3.6 83 6 1.4 2 158 58 25 105 11 3.3 86 6 1.4 3 148 55 22 104 11 3.1 82 6 1.3 4 143 51 20 126 10 3.6 81 6 1.2 5 175 101 53 108 10 2.9 80 5 1.1 6 340 317 296 105 9 2.7 77 5 1.1 7 278 240 184 104 9 2.5 75 5 1.1 8 209 113 64 97 8 2.1 80 6 1.2 9 181 89 44 95 7 1.8 83 6 1.3 10 161 77 33 96 6 1.6 86 11 2.9 11 149 64 26 94 6 1.5 122 51 19 12 142 52 20 90 6 1.5 167 65 38 13 137 45 17 89 6 1.4 90 25 6.2 14 136 44 16 88 5 1.1 83 22 5.0 15 136 43 16 87 4 0.90 76 19 3.8 16 132 41 15 84 3 0.73 76 17 3.6 17 129 40 14 82 4 0.86 142 63 32 18 124 39 13 82 5 1.0 81 19 4.2 19 122 38 12 253 203 207 92 22 5.6 20 117 36 12 268 196 158 81 12 2.7 21 119 35 11 135 66 25 e83 e8 e1.6 22 117 34 11 104 26 7.3 e81 e5 e1.1 23 126 33 11 94 14 3.7 e77 e5 e1.1 24 150 55 23 89 5 1.2 e73 e5 e1.1 25 131 43 15 85 5 1.2 e75 e5 e1.1 26 115 16 5.0 91 6 1.5 e73 e5 e1.1 27 114 14 4.4 99 7 1.8 e73 e5 e1.1 28 115 14 4.3 85 7 1.6 e83 e6 e1.3 29 129 13 4.7 --- --- --- 319 277 839 30 118 13 4.1 --- --- --- 351 323 411 31 112 12 3.8 --- --- --- 189 120 67 TOTAL 4627 --- 1026.3 3052 --- 444.49 3300 --- 1460.6 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) APRIL MAY JUNE 1 164 46 23 442 337 483 141 7 2.7 2 122 21 7.0 472 395 636 140 7 2.5 3 104 18 5.2 403 200 253 188 72 66 4 84 16 3.6 316 27 23 191 83 44 5 96 29 11 267 20 15 542 494 1170 6 261 191 146 255 14 9.4 323 296 292 7 247 226 176 224 13 8.6 186 33 18 8 697 780 1640 284 188 155 144 9 3.5 9 526 566 816 210 8 4.4 138 6 2.3 10 303 115 106 194 7 3.5 129 3 1.2 11 200 43 23 185 7 3.4 117 2 0.54 12 157 28 12 183 11 5.2 113 2 0.69 13 129 16 5.6 177 15 7.0 110 3 0.75 14 117 15 4.7 168 17 7.8 107 3 0.80 15 118 15 4.9 166 15 6.5 104 3 0.82 16 186 78 40 164 12 5.1 107 3 0.75 17 212 109 64 161 9 3.8 110 2 0.68 18 455 457 1770 155 6 2.5 128 2 0.74 19 531 638 1100 156 5 2.2 120 3 0.83 20 829 923 3210 151 5 1.9 109 3 0.91 21 1360 1600 7070 141 4 1.5 102 4 0.99 22 527 627 918 137 3 1.3 104 4 1.1 23 965 1080 5330 135 3 1.1 102 3 0.89 24 1360 1460 7370 132 2 0.87 101 3 0.70 25 2540 2890 35300 131 2 0.81 101 2 0.55 26 2280 2390 21400 133 3 1.2 99 2 0.47 27 1460 1610 7760 135 5 1.8 102 2 0.43 28 682 776 1530 138 6 2.2 100 1 0.37 29 716 668 3120 129 6 2.1 96 1 0.30 30 616 714 1310 206 79 79 95 1 0.31 31 --- --- --- 222 124 99 --- --- --- TOTAL 18044 --- 100276.0 6372 --- 1827.18 4249 --- 1615.82 183 RIO GRANDE DE MANATI BASIN 50035000 RIO GRANDE DE MANATI AT CIALES, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) JULY AUGUST SEPTEMBER 1 93 2 0.54 154 66 61 102 23 6.4 2 93 3 0.79 186 75 48 319 303 963 3 92 4 0.98 115 30 10 1090 1080 4350 4 91 4 0.98 122 37 13 595 651 1250 5 90 4 0.97 118 26 9.0 223 137 90 6 94 5 1.2 95 10 2.6 138 57 21 7 104 7 2.1 85 8 1.7 113 41 12 8 92 7 1.7 89 7 1.7 103 27 7.4 9 90 6 1.4 96 12 3.9 96 22 5.7 10 90 5 1.1 120 26 9.4 94 18 4.6 11 93 8 2.5 164 93 84 91 15 3.6 12 136 72 36 234 179 175 88 11 2.6 13 137 43 18 109 32 9.7 85 7 1.7 14 94 2 0.63 100 10 2.7 102 17 6.4 15 94 2 0.42 97 5 1.4 123 6 2.0 16 89 1 0.26 85 5 1.1 193 89 54 17 89 1 0.29 89 4 1.0 124 9 3.4 18 87 1 0.32 82 4 0.78 256 207 339 19 85 2 0.35 83 3 0.69 360 336 494 20 82 2 0.37 82 3 0.70 263 217 207 21 82 2 0.41 77 3 0.69 296 250 271 22 84 2 0.46 76 3 0.71 138 30 12 23 85 2 0.51 91 4 0.88 115 13 4.0 24 84 2 0.55 88 4 0.89 116 20 6.2 25 81 3 0.57 85 4 0.89 164 67 30 26 79 3 0.60 78 4 0.81 182 98 68 27 85 3 0.69 75 3 0.65 194 100 58 28 92 3 0.80 73 3 0.51 128 36 13 29 98 3 0.90 76 2 0.45 154 61 27 30 84 4 0.82 91 5 1.3 118 27 8.8 31 84 4 0.86 119 36 12 --- --- --- TOTAL 2853 --- 78.07 3234 --- 457.15 6163 --- 8321.8 e Estimated 184 RIO GRANDE DE MANATI BASIN 50035500 RIO GRANDE DE MANATI AT HIGHWAY 149 AT CIALES, PR 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 Río Cialitos, 0.5 mi (0.8 km) north of Ciales Plaza. DRAINAGE AREA.--136 mi2 (352 km2) this excludes the 6 mi2 (15.5 km2) upstream from Lago El Guineo and Lago de Matrullas, flow from which is diverted to Río Jacaguas. PERIOD OF RECORD.--Water years 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 TURBID- FECAL FECAL SPECIF. PH, ITY, DIS- COD, COLI- STREP- HARD- INSTAN- CONDUC- WATER, WAT UNF SOLVED HIGH FORM, TOCOCCI NESS, TANEOUS TANCE, UNFLTRD TEMPER- LAB, DIS- OXYGEN, LEVEL, M-FC KF WATER, CALCIUM DIS- WAT UNF FIELD, ATURE, HACH SOLVED PERCENT WATER, 0.7U MF MF, UNFLTRD WATER, DATE TIME CHARGE, US/CM STD WATER, 2100AN OXYGEN, OF SAT- UNFLTRD COL/ COL/ MG/L AS FLTRD, CFS 25 DEGC UNITS DEG C NTU MG/L URATION MG/L 100 ML 100 ML CACO3 MG/L (00061) (00095) (00400) (00010) (99872) (00300) (00301) (00340) (31625) (31673) (00900) (00915) NOV 27... 1215 154 234 7.2 23.3 2.0 9.5 111 <10 590 730 92 24.3 MAR 14... 0810 100 238 7.2 23.8 2.2 7.5 89 <10 310 250 -- -- MAY 13... 1130 -- -- -- -- 2.9 -- -- <10 -- -- 91 22.9 ANC, RESIDUE RESIDUE WAT UNF WATER, TOTAL MAGNES- POTAS- FIXED CHLOR- FLUOR- FLTRD, AT 105 IUM, SODIUM, SODIUM SIUM, END PT, SULFIDE SULFATE IDE, IDE, SILICA, SUM OF RESIDUE DEG. C, WATER, WATER, ADSORP- WATER, FIELD, WATER WATER, WATER, WATER, WATER, CONSTI- WATER, SUS- DATE FLTRD, FLTRD, TION FLTRD, MG/L AS UNFLTRD FLTRD, FLTRD, FLTRD, FLTRD, TUENTS FLTRD, PENDED, MG/L MG/L RATIO MG/L CACO3 MG/L MG/L MG/L MG/L MG/L MG/L TONS/D MG/L (00925) (00930) (00931) (00935) (00410) (00745) (00945) (00940) (00950) (00955) (70301) (70302) (00530) NOV 27... 7.59 10.7 .5 1.87 90 <1.0 7.7 12.1 E.1 22.1 140 58.4 <10 MAR 14... -- -- -- -- 93 -- -- -- -- -- -- -- <10 MAY 13... 8.18 10.4 .5 1.71 -- <.1 7.0 11.1 <.1 23.0 140 -- <10 NITRITE AMMONIA CHROM- + + BARIUM, BORON, IUM, COPPER, IRON, LEAD, NITRITE NITRATE AMMONIA ORG-N, PHOS- WATER, WATER, WATER, WATER, WATER, WATER, WATER, WATER WATER, WATER, PHORUS, ARSENIC UNFLTRD UNFLTRD CADMIUM UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD WATER, WATER RECOV- RECOV- WATER, RECOV- RECOV- RECOV- RECOV- DATE MG/L MG/L MG/L MG/L UNFLTRD UNFLTRD ERABLE, ERABLE, UNFLTRD ERABLE, ERABLE, ERABLE, ERABLE, AS N AS N AS N AS N MG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L (00615) (00630) (00610) (00625) (00665) (01002) (01007) (01022) (01027) (01034) (01042) (01045) (01051) NOV 27... .01 .350 .03 <.20 E.03 <2 42.7 20 <.1 <.8 M 50 <1 MAR 14... <.01 .460 .01 <.20 .06 -- -- -- -- -- -- -- -- MAY 13... <.01 .190 <.01 .30 .02 <2 41.1 E20 <.1 E.5 <10 150 <1 MANGAN- PHEN- ESE, MERCURY SILVER, ZINC, OLIC WATER, WATER, SELEN- WATER, WATER, COM- UNFLTRD UNFLTRD IUM, UNFLTRD UNFLTRD CYANIDE POUNDS, MBAS, RECOV- RECOV- WATER, RECOV- RECOV- WATER WATER, WATER, DATE ERABLE, ERABLE, UNFLTRD ERABLE, ERABLE, UNFLTRD UNFLTRD UNFLTRD UG/L UG/L UG/L UG/L UG/L MG/L UG/L MG/L (01055) (71900) (01147) (01077) (01092) (00720) (32730) (38260) NOV 27... 14.9 <.01 <2 <.3 <20 <.01 E1 <.05 MAR 14... -- -- -- -- -- -- -- -- MAY 13... 17.3 <.01 <2 <.3 <20 <.01 <16 <.05 < -- Less than E -- Estimated value M -- Presence verified, not quantified 185 RIO GRANDE DE MANATI BASIN 50035950 RIO CIALITOS AT HIGHWAY 649 AT CIALES, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°20'18", long 66°28'28", 100 ft (30 m) upstream from bridge on Highway 649, 0.7 mi (1.1 km) upstream from mouth, and about 0.4 mi (0.6 km) west of Ciales Plaza. DRAINAGE AREA.--17.0 mi2 (44.0 km2). PERIOD OF RECORD.--Water years 1969-71, 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 TURBID- FECAL FECAL SPECIF. PH, ITY, DIS- COD, COLI- STREP- HARD- INSTAN- CONDUC- WATER, WAT UNF SOLVED HIGH FORM, TOCOCCI NESS, TANEOUS TANCE, UNFLTRD TEMPER- LAB, DIS- OXYGEN, LEVEL, M-FC KF WATER, CALCIUM DIS- WAT UNF FIELD, ATURE, HACH SOLVED PERCENT WATER, 0.7U MF MF, UNFLTRD WATER, DATE TIME CHARGE, US/CM STD WATER, 2100AN OXYGEN, OF SAT- UNFLTRD COL/ COL/ MG/L AS FLTRD, CFS 25 DEGC UNITS DEG C NTU MG/L URATION MG/L 100 ML 100 ML CACO3 MG/L (00061) (00095) (00400) (00010) (99872) (00300) (00301) (00340) (31625) (31673) (00900) (00915) NOV 21... 0830 31 240 7.6 22.1 3.0 8.2 95 <10 330 350 94 28.0 MAR 14... 0935 16 213 7.4 21.8 13 8.4 96 <10 E793 880 -- -- AUG 29... 1315 13 208 7.5 28.5 5.8 8.7 113 <10 360 210 94 26.4 ANC, RESIDUE RESIDUE WAT UNF WATER, TOTAL MAGNES- POTAS- FIXED CHLOR- FLUOR- FLTRD, AT 105 IUM, SODIUM, SODIUM SIUM, END PT, SULFIDE SULFATE IDE, IDE, SILICA, SUM OF RESIDUE DEG. C, WATER, WATER, ADSORP- WATER, FIELD, WATER WATER, WATER, WATER, WATER, CONSTI- WATER, SUS- DATE FLTRD, FLTRD, TION FLTRD, MG/L AS UNFLTRD FLTRD, FLTRD, FLTRD, FLTRD, TUENTS FLTRD, PENDED, MG/L MG/L RATIO MG/L CACO3 MG/L MG/L MG/L MG/L MG/L MG/L TONS/D MG/L (00925) (00930) (00931) (00935) (00410) (00745) (00945) (00940) (00950) (00955) (70301) (70302) (00530) NOV 21... 5.95 10.1 .5 1.86 90 <1.0 6.2 12.1 E.1 27.7 146 12.0 <10 MAR 14... -- -- -- -- 74 -- -- -- -- -- -- -- <10 AUG 29... 6.75 10.0 .5 1.54 84 <.1 5.4 10.1 E.09 29.1 140 4.98 <10 NITRITE AMMONIA CHROM- + + BARIUM, BORON, IUM, COPPER, IRON, LEAD, NITRITE NITRATE AMMONIA ORG-N, PHOS- WATER, WATER, WATER, WATER, WATER, WATER, WATER, WATER WATER, WATER, PHORUS, ARSENIC UNFLTRD UNFLTRD CADMIUM UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD WATER, WATER RECOV- RECOV- WATER, RECOV- RECOV- RECOV- RECOV- DATE MG/L MG/L MG/L MG/L UNFLTRD UNFLTRD ERABLE, ERABLE, UNFLTRD ERABLE, ERABLE, ERABLE, ERABLE, AS N AS N AS N AS N MG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L (00615) (00630) (00610) (00625) (00665) (01002) (01007) (01022) (01027) (01034) (01042) (01045) (01051) NOV 21... <.01 .900 .02 <.20 E.04 <2 44.3 20 <.1 <.8 <10 50 <1 MAR 14... <.01 1.10 <.01 <.20 .08 -- -- -- -- -- -- -- -- AUG 29... <.01 .350 .02 .40 .07 <2 45.1 E20 E.1 <.8 <10 130 <1 MANGAN- PHEN- ESE, MERCURY SILVER, ZINC, OLIC WATER, WATER, SELEN- WATER, WATER, COM- UNFLTRD UNFLTRD IUM, UNFLTRD UNFLTRD CYANIDE POUNDS, MBAS, RECOV- RECOV- WATER, RECOV- RECOV- WATER WATER, WATER, DATE ERABLE, ERABLE, UNFLTRD ERABLE, ERABLE, UNFLTRD UNFLTRD UNFLTRD UG/L UG/L UG/L UG/L UG/L MG/L UG/L MG/L (01055) (71900) (01147) (01077) (01092) (00720) (32730) (38260) NOV 21... 6.9 <.01 <2 <.3 <20 <.01 <16 <.05 MAR 14... -- -- -- -- -- -- -- -- AUG 29... 13.6 <.01 <2 <.3 E10 <.01 <16 <.05 < -- Less than E -- Estimated value 186 RIO GRANDE DE MANATI BASIN 50038100 RIO GRANDE DE MANATI AT HIGHWAY 2 NEAR MANATI, PR LOCATION.--Lat 18°25'52", long 66°31'37", Hydrologic Unit 21010002, at bridge on Highway 2, and 2.3 mi (3.7 km) west of Manatí. DRAINAGE AREA.--197 mi2 (510 km2), approximately, of which about 38 mi2 (98 km2) is partly or entirely noncontributing, excludes 6.0 mi2 (15.5 km2) 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. Possible water extraction about 500 ft (152.4 m) upstream of gage by unknown source affecting low flow. EXTREMES OUTSIDE PERIOD OF RECORD.--Approximate gage heights to gage datum of major floods, pointed out by local residents, are as follows: September 13, 1928, 36.6 ft (11.16 m), September 27, 1932, 36.3 ft (11.06 m), and August 4, 1945, 34.3 ft (10.45 m). Discharge, cubic feet per second WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 117 112 195 244 146 105 162 1120 183 114 119 126 2 111 355 495 232 140 106 137 1070 173 111 257 114 3 108 356 862 225 137 105 120 978 170 112 178 1380 4 113 212 420 217 147 104 106 622 264 111 163 1470 5 125 178 427 234 147 101 105 505 530 110 189 581 6 116 226 298 409 135 101 362 447 554 108 126 290 7 114 287 238 390 140 101 315 399 251 123 112 185 8 e110 43500 222 285 131 104 1030 427 192 116 107 155 9 e130 17300 203 243 128 108 958 347 179 109 111 140 10 e200 2180 192 213 128 105 596 302 167 118 149 131 11 e140 1030 188 188 127 128 394 284 153 110 141 126 12 e130 680 197 179 124 192 269 269 145 132 391 124 13 e115 522 238 173 121 129 228 249 141 211 153 119 14 e110 408 253 170 120 111 210 233 137 127 114 117 15 e170 373 251 168 119 104 211 224 133 111 126 186 16 220 355 241 165 117 99 268 250 130 111 104 258 17 177 314 748 164 116 138 325 223 132 107 96 224 18 155 289 572 156 114 112 279 212 149 109 94 372 19 142 e277 368 153 168 102 1260 207 156 104 89 932 20 128 e255 301 149 341 112 835 204 139 101 88 846 21 120 e242 489 148 173 98 2730 188 130 99 85 577 22 115 e227 805 147 131 94 920 183 126 100 81 251 23 113 e212 1080 156 118 92 1120 177 126 105 90 191 24 111 e273 2020 171 112 89 2340 177 128 104 100 174 25 108 e300 846 177 108 87 4290 170 127 102 94 225 26 105 e212 500 155 108 86 6810 169 121 97 87 227 27 104 e200 377 152 119 85 4430 169 123 99 80 362 28 111 e190 324 151 111 90 1790 175 123 109 77 219 29 171 e202 285 163 --- 126 982 163 120 119 76 214 30 137 232 268 157 --- 613 2030 179 116 114 92 184 31 119 --- 262 150 --- 204 --- 300 --- 101 131 --- TOTAL 4045 71499 14165 6084 3826 3931 35612 10622 5318 3504 3900 10500 MEAN 130 2383 457 196 137 127 1187 343 177 113 126 350 MAX 220 43500 2020 409 341 613 6810 1120 554 211 391 1470 MIN 104 112 188 147 108 85 105 163 116 97 76 114 AC-FT 8020 141800 28100 12070 7590 7800 70640 21070 10550 6950 7740 20830 CFSM 0.66 12.1 2.32 1.00 0.69 0.64 6.03 1.74 0.90 0.57 0.64 1.78 IN. 0.76 13.50 2.67 1.15 0.72 0.74 6.72 2.01 1.00 0.66 0.74 1.98 STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1970 - 2002, BY WATER YEAR (WY) MEAN 701 648 420 267 206 178 359 620 238 152 208 605 MAX 2958 2383 1717 879 444 521 1187 3178 815 577 1644 3732 (WY) 1971 2002 2000 1997 1988 1972 2002 1985 1999 1979 1979 1998 MIN 130 71.0 55.1 59.1 72.0 56.2 49.9 93.7 63.8 53.0 67.9 67.4 (WY) 2002 1995 1998 1995 1994 1994 1995 1989 1994 1994 1984 1994 e Estimated 187 RIO GRANDE DE MANATI BASIN 50038100 RIO GRANDE DE MANATI AT HIGHWAY 2 NEAR MANATI, PR--Continued SUMMARY STATISTICS FOR 2001 CALENDAR YEAR FOR 2002 WATER YEAR WATER YEARS 1970 - 2002 ANNUAL TOTAL 128927 173006 ANNUAL MEAN 353 474 382 HIGHEST ANNUAL MEAN 756 1971 LOWEST ANNUAL MEAN 96.5 1994 HIGHEST DAILY MEAN 43500 Nov 8 43500 Nov 8 80400 Sep 22 1998 LOWEST DAILY MEAN 62 May 5 76 Aug 29 31 Jan 24 1995 ANNUAL SEVEN-DAY MINIMUM 67 Jun 10 86 Aug 23 33 Jul 23 1994 MAXIMUM PEAK FLOW 104000 Nov 8 198000 Sep 10 1996 MAXIMUM PEAK STAGE 34.01 Nov 8 36.39 Sep 10 1996 INSTANTANEOUS LOW FLOW 75 Aug 28 28 Jan 23 1995 ANNUAL RUNOFF (AC-FT) 255700 343200 276900 ANNUAL RUNOFF (CFSM) 1.79 2.41 1.94 ANNUAL RUNOFF (INCHES) 24.35 32.67 26.36 10 PERCENT EXCEEDS 355 579 676 50 PERCENT EXCEEDS 115 163 165 90 PERCENT EXCEEDS 75 104 82 O N D 2001 J F M A M J J A S 2002 10 20 50 100 100 200 500 1000 1000 2000 5000 10,000 10,000 20,000 50,000 100,000 DISCHARGE, IN CUBIC FEET PER SECOND 188 RIO GRANDE DE MANATI BASIN 50038100 RIO GRANDE DE MANATI AT HIGHWAY 2 NEAR MANATI, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1969 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 TURBID- FECAL FECAL SPECIF. PH, ITY, DIS- COD, COLI- STREP- HARD- INSTAN- CONDUC- WATER, WAT UNF SOLVED HIGH FORM, TOCOCCI NESS, TANEOUS TANCE, UNFLTRD TEMPER- LAB, DIS- OXYGEN, LEVEL, M-FC KF WATER, CALCIUM DIS- WAT UNF FIELD, ATURE, HACH SOLVED PERCENT WATER, 0.7U MF MF, UNFLTRD WATER, DATE TIME CHARGE, US/CM STD WATER, 2100AN OXYGEN, OF SAT- UNFLTRD COL/ COL/ MG/L AS FLTRD, CFS 25 DEGC UNITS DEG C NTU MG/L URATION MG/L 100 ML 100 ML CACO3 MG/L (00061) (00095) (00400) (00010) (99872) (00300) (00301) (00340) (31625) (31673) (00900) (00915) NOV 27... 1510 201 282 7.5 26.6 5.2 8.5 106 <10 2200 630 120 35.7 MAR 07... 1230 101 319 7.7 26.0 5.7 10.7 132 <10 E12000 980 -- -- MAY 13... 1400 -- -- -- -- 6.5 -- -- <10 -- -- 110 33.5 ANC, RESIDUE RESIDUE WAT UNF WATER, TOTAL MAGNES- POTAS- FIXED CHLOR- FLUOR- FLTRD, AT 105 IUM, SODIUM, SODIUM SIUM, END PT, SULFIDE SULFATE IDE, IDE, SILICA, SUM OF RESIDUE DEG. C, WATER, WATER, ADSORP- WATER, FIELD, WATER WATER, WATER, WATER, WATER, CONSTI- WATER, SUS- DATE FLTRD, FLTRD, TION FLTRD, MG/L AS UNFLTRD FLTRD, FLTRD, FLTRD, FLTRD, TUENTS FLTRD, PENDED, MG/L MG/L RATIO MG/L CACO3 MG/L MG/L MG/L MG/L MG/L MG/L TONS/D MG/L (00925) (00930) (00931) (00935) (00410) (00745) (00945) (00940) (00950) (00955) (70301) (70302) (00530) NOV 27... 7.42 10.2 .4 1.91 120 <1.0 8.2 12.8 E.1 18.8 167 90.5 <10 MAR 07... -- -- -- -- 133 -- -- -- -- -- -- -- <10 MAY 13... 7.49 10.2 .4 1.83 -- <.1 7.2 10.9 <.1 21.2 160 -- <10 NITRITE AMMONIA CHROM- + + BARIUM, BORON, IUM, COPPER, IRON, LEAD, NITRITE NITRATE AMMONIA ORG-N, PHOS- WATER, WATER, WATER, WATER, WATER, WATER, WATER, WATER WATER, WATER, PHORUS, ARSENIC UNFLTRD UNFLTRD CADMIUM UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD WATER, WATER RECOV- RECOV- WATER, RECOV- RECOV- RECOV- RECOV- DATE MG/L MG/L MG/L MG/L UNFLTRD UNFLTRD ERABLE, ERABLE, UNFLTRD ERABLE, ERABLE, ERABLE, ERABLE, AS N AS N AS N AS N MG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L (00615) (00630) (00610) (00625) (00665) (01002) (01007) (01022) (01027) (01034) (01042) (01045) (01051) NOV 27... .01 .510 .02 <.20 E.04 <2 44.3 30 <.1 <.8 <10 230 <1 MAR 07... <.01 .450 .05 .20 .08 -- -- -- -- -- -- -- -- MAY 13... <.01 .500 .02 .40 .06 <2 48.1 E10 <.1 1.0 M 640 <1 MANGAN- PHEN- ESE, MERCURY SILVER, ZINC, OLIC WATER, WATER, SELEN- WATER, WATER, COM- UNFLTRD UNFLTRD IUM, UNFLTRD UNFLTRD CYANIDE POUNDS, MBAS, RECOV- RECOV- WATER, RECOV- RECOV- WATER WATER, WATER, DATE ERABLE, ERABLE, UNFLTRD ERABLE, ERABLE, UNFLTRD UNFLTRD UNFLTRD UG/L UG/L UG/L UG/L UG/L MG/L UG/L MG/L (01055) (71900) (01147) (01077) (01092) (00720) (32730) (38260) NOV 27... 49.3 <.01 <2 <.3 <20 <.01 E18 <.05 MAR 07... -- -- -- -- -- -- -- -- MAY 13... 60.5 <.01 <2 <.3 <20 <.01 <16 <.05 189 RIO GRANDE DE MANATI BASIN 50038100 RIO GRANDE DE MANATI AT HIGHWAY 2 NEAR MANATI, PR--Continued WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 PESTICIDE ANALYSES CHLOR- DI- CARBO- DANE, ALPHA- CHLOR- PHENO- TECH- CHLOR- TRIBU- DIAZI- DIEL- DISUL- ENDO- PROP, 2,4,5-T 2,4-D ALDRIN, THION, NICAL, PYRIFOS PHOS, NON, DRIN, FOTON, SULFAN, WATER, WATER WATER WATER, WATER, WATER, WATER WATER, WATER, WATER, WATER, WATER, DATE TIME UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L (82183) (39740) (39730) (39330) (39786) (39350) (38932) (39040) (39570) (39380) (39011) (39388) MAY 13... 1400 <.02 <.01 <.02 <.01 <.02 <.1 <.01 <.02 <.02 <.006 <.10 <.02 P,P'- HEPTA- METH- METHYL CHLOR HEPTA- MALA- OXY- PARA- P,P'- P,P'- P,P'- ENDRIN, ETHION, FONOFOS EPOXIDE CHLOR, LINDANE THION, CHLOR, THION, MIREX, DDD, DDE, DDT, WATER, WATER, WATER WATER WATER, WATER, WATER, WATER, WATER, WATER, WATER, WATER, WATER, DATE UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L (39390) (39398) (82614) (39420) (39410) (39340) (39530) (39480) (39600) (39755) (39360) (39365) (39370) MAY 13... <.01 <.01 <.01 <.009 <.01 <.006 <.10 <.020 <.02 <.006 <.007 <.006 <.009 PARA- TOXA- THION, PCBS, PHORATE SILVEX, PHENE, WATER, WATER, WATER WATER, WATER, DATE UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UG/L UG/L UG/L UG/L UG/L (39540) (39516) (39023) (39760) (39400) MAY 13... <.01 <.1 <.02 <.02 <1 < -- Less than E -- Estimated value M -- Presence verified, not quantified 190 LAGUNA TORTUGUERO BASIN 50038200 LAGUNA TORTUGUERO 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 Manatí, and 4.4 mi (7.1 km) northwest of Vega Baja Plaza. DRAINAGE AREA.--Indeterminate. PERIOD OF RECORD.--Water years 1964-66, 1969-71, 1974 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 FECAL FECAL ANC, RESIDUE SPECIF. PH, DIS- COD, COLI- STREP- WAT UNF TOTAL INSTAN- CONDUC- WATER, SOLVED HIGH FORM, TOCOCCI FIXED AT 105 NITRITE TANEOUS TANCE, UNFLTRD TEMPER- DIS- OXYGEN, LEVEL, M-FC KF END PT, SULFIDE DEG. C, WATER, DIS- WAT UNF FIELD, ATURE, SOLVED PERCENT WATER, 0.7U MF MF, FIELD, WATER SUS- UNFLTRD DATE TIME CHARGE, US/CM STD WATER, OXYGEN, OF SAT- UNFLTRD COL/ COL/ MG/L AS UNFLTRD PENDED, MG/L CFS 25 DEGC UNITS DEG C MG/L URATION MG/L 100 ML 100 ML CACO3 MG/L MG/L AS N (00061) (00095) (00400) (00010) (00300) (00301) (00340) (31625) (31673) (00410) (00745) (00530) (00615) NOV 19... 1015 40 996 7.3 27.8 5.2 66 30 E48 E34 113 <1.0 <10 .02 MAR 06... 0930 7.9 933 7.7 25.6 7.0 86 30 100 92 132 -- <10 .01 MAY 06... 1115 -- -- -- -- -- -- 30 -- -- -- <1.0 <10 .01 SEP 03... 0840 -- 1100 7.1 28.7 5.8 75 30 E73 E64 110 <.1 <10 .01 NITRITE AMMONIA TOTAL MANGAN- PHEN- + + NITRO- BORON, COPPER, IRON, ESE, ZINC, OLIC NITRATE AMMONIA ORG-N, GEN, PHOS- WATER, WATER, WATER, WATER, WATER, COM- WATER WATER, WATER, WATER, PHORUS, UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD CYANIDE POUNDS, MBAS, UNFLTRD UNFLTRD UNFLTRD UNFLTRD WATER, RECOV- RECOV- RECOV- RECOV- RECOV- WATER WATER, WATER, DATE MG/L MG/L MG/L MG/L UNFLTRD ERABLE, ERABLE, ERABLE, ERABLE, ERABLE, UNFLTRD UNFLTRD UNFLTRD AS N AS N AS N AS NO3 MG/L UG/L UG/L UG/L UG/L UG/L MG/L UG/L MG/L (00630) (00610) (00625) (71887) (00665) (01022) (01042) (01045) (01055) (01092) (00720) (32730) (38260) NOV 19... .460 .31 E1.1 -- E.02 50 <10 100 7.2 <20 <.01 <16 .06 MAR 06... .550 .12 .80 6.0 <.02 -- -- -- -- -- -- -- -- MAY 06... .280 .12 1.1 6.1 <.02 60 M 40 3.9 M M <16 .12 SEP 03... .560 .26 1.5 9.1 <.02 60 <10 M E1.5 <20 <.01 <16 .13 < -- Less than E -- Estimated value M -- Presence verified, not quantified 191 Figure 15. Río Cibuco basin. 192 RIO CIBUCO BASIN 50038320 RIO CIBUCO BELOW COROZAL, PR LOCATION.--Lat l8°21'13", long 66°20'07", Hydrologic Unit 21010001, on right bank, 150 ft (46 m) downstream from junction with Río Corozal and 1.4 mi (2.3 km) northwest of Corozal. DRAINAGE AREA.--15.1 mi2 (39.1 km2). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--May 1969 to current year. GAGE.--Water-stage recorder. Elevation of gage is 195 ft (59 m), from topographic map. REMARKS.--Records fair except those for estimated daily discharges, which are poor. Gage-height and precipitation satellite telemetry at station. Daily discharge affected by sewage treatment plant about 0.6 mi (1.0 km) upstream from station. Discharge, cubic feet per second WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 5.6 5.7 14 12 18 12 18 440 14 9.1 6.4 16 2 5.4 5.9 27 12 15 12 18 138 15 9.3 14 55 3 6.0 5.7 58 13 28 12 15 53 14 9.0 15 223 4 13 5.8 159 12 30 10 11 46 15 8.8 12 91 5 10 6.1 100 19 18 11 18 57 15 8.5 7.4 23 6 7.2 7.0 39 82 21 8.8 100 50 14 11 7.1 15 7 6.1 67 32 48 23 9.0 160 36 14 11 6.5 13 8 18 3190 24 20 20 14 146 31 13 8.8 6.5 12 9 11 248 20 15 18 9.3 41 28 13 8.6 6.3 12 10 55 89 26 14 17 12 25 26 12 8.4 5.7 11 11 16 43 40 13 21 14 21 25 12 8.3 5.6 11 12 8.8 29 95 12 17 11 18 24 14 99 5.5 11 13 8.1 26 54 12 18 9.2 17 23 12 18 5.7 11 14 40 23 63 12 18 9.0 16 22 11 9.8 14 80 15 170 21 47 12 17 8.9 38 21 11 8.4 9.3 43 16 24 18 52 15 17 8.5 48 21 10 8.5 10 56 17 15 17 191 15 16 8.3 29 20 14 8.0 6.9 21 18 11 17 64 14 16 8.4 24 20 18 6.8 7.2 21 19 9.4 16 30 12 60 8.9 19 18 14 6.3 6.5 41 20 8.1 15 18 12 21 7.5 164 18 15 6.4 5.5 316 21 7.7 15 18 11 12 7.1 98 17 12 6.7 5.7 81 22 7.4 15 17 13 11 7.3 37 17 12 7.0 5.8 41 23 8.1 14 294 12 11 6.4 27 17 11 7.4 19 33 24 7.0 16 89 24 10 5.8 63 16 11 8.1 8.1 81 25 6.8 17 34 13 10 5.5 103 16 10 7.3 6.7 47 26 7.4 14 22 13 13 5.7 277 16 11 6.5 6.5 38 27 6.3 14 16 14 13 6.2 121 17 11 12 6.3 34 28 6.2 14 14 27 11 62 44 16 10 13 7.3 27 29 7.4 19 13 e16 --- 30 35 16 9.6 9.1 7.5 25 30 6.2 15 13 e51 --- 14 77 22 9.4 7.0 38 22 31 5.5 --- 13 27 --- 13 --- 16 --- 6.4 21 --- TOTAL 523.7 4008.2 1696 597 520 366.8 1828 1303 377.0 362.5 295.0 1511 MEAN 16.9 134 54.7 19.3 18.6 11.8 60.9 42.0 12.6 11.7 9.52 50.4 MAX 170 3190 294 82 60 62 277 440 18 99 38 316 MIN 5.4 5.7 13 11 10 5.5 11 16 9.4 6.3 5.5 11 AC-FT 1040 7950 3360 1180 1030 728 3630 2580 748 719 585 3000 CFSM 1.12 8.85 3.62 1.28 1.23 0.78 4.04 2.78 0.83 0.77 0.63 3.34 IN. 1.29 9.87 4.18 1.47 1.28 0.90 4.50 3.21 0.93 0.89 0.73 3.72 STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1969 - 2002, BY WATER YEAR (WY) MEAN 41.2 51.8 40.1 24.9 21.2 20.1 31.1 41.8 14.9 12.2 15.9 33.6 MAX 135 155 169 69.6 51.3 65.1 111 157 44.4 35.6 50.8 191 (WY) 1991 1971 1971 1992 1988 1981 1973 1986 1987 1999 1979 1996 MIN 8.05 5.63 1.94 6.93 7.75 4.36 3.32 3.20 1.63 2.19 3.44 3.88 (WY) 1979 1998 1998 1995 1994 1984 1984 1977 1994 1994 1978 1994 SUMMARY STATISTICS FOR 2001 CALENDAR YEAR FOR 2002 WATER YEAR WATER YEARS 1969 - 2002 ANNUAL TOTAL 8792.4 13388.2 ANNUAL MEAN 24.1 36.7 29.2 HIGHEST ANNUAL MEAN 56.5 1971 LOWEST ANNUAL MEAN 7.47 1994 HIGHEST DAILY MEAN 3190 Nov 8 3190 Nov 8 3190 Nov 8 2001 LOWEST DAILY MEAN 3.9 Jul 15 5.4 Oct 2 0.91 Jul 17 1994 ANNUAL SEVEN-DAY MINIMUM 4.2 Jul 11 5.8 Oct 30 1.2 Jun 21 1994 MAXIMUM PEAK FLOW 21400 Nov 8 21400 Nov 8 2001 MAXIMUM PEAK STAGE 22.68 Nov 8 22.68 Nov 8 2001 ANNUAL RUNOFF (AC-FT) 17440 26560 21120 ANNUAL RUNOFF (CFSM) 1.60 2.43 1.93 ANNUAL RUNOFF (INCHES) 21.66 32.98 26.24 10 PERCENT EXCEEDS 26 57 52 50 PERCENT EXCEEDS 7.6 14 13 90 PERCENT EXCEEDS 5.3 6.6 5.2 e Estimated 193 RIO CIBUCO BASIN 50038320 RIO CIBUCO BELOW COROZAL, PR--Continued O N D 2001 J F M A M J J A S 2002 1 2 5 10 10 20 50 100 100 200 500 1000 1000 2000 5000 10,000 DISCHARGE, IN CUBIC FEET PER SECOND 194 RIO CIBUCO BASIN 50038320 RIO CIBUCO BELOW COROZAL, PR WATER-QUALITY RECORDS PERIOD OF RECORD.--Water years 1969-76, 1979 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 TURBID- FECAL FECAL SPECIF. PH, ITY, DIS- COD, COLI- STREP- HARD- INSTAN- CONDUC- WATER, WAT UNF SOLVED HIGH FORM, TOCOCCI NESS, TANEOUS TANCE, UNFLTRD TEMPER- LAB, DIS- OXYGEN, LEVEL, M-FC KF WATER, CALCIUM DIS- WAT UNF FIELD, ATURE, HACH SOLVED PERCENT WATER, 0.7U MF MF, UNFLTRD WATER, DATE TIME CHARGE, US/CM STD WATER, 2100AN OXYGEN, OF SAT- UNFLTRD COL/ COL/ MG/L AS FLTRD, CFS 25 DEGC UNITS DEG C NTU MG/L URATION MG/L 100 ML 100 ML CACO3 MG/L (00061) (00095) (00400) (00010) (99872) (00300) (00301) (00340) (31625) (31673) (00900) (00915) NOV 20... 1020 15 391 7.4 23.9 2.1 8.2 98 <10 5200 460 150 39.9 MAR 21... 0910 8.8 393 7.6 23.7 2.1 8.1 96 <10 2700 590 -- -- MAY 08... 1200 -- -- -- -- 6.8 -- -- <10 -- -- 160 44.6 ANC, RESIDUE RESIDUE WAT UNF WATER, TOTAL MAGNES- POTAS- FIXED CHLOR- FLUOR- FLTRD, AT 105 IUM, SODIUM, SODIUM SIUM, END PT, SULFIDE SULFATE IDE, IDE, SILICA, SUM OF RESIDUE DEG. C, WATER, WATER, ADSORP- WATER, FIELD, WATER WATER, WATER, WATER, WATER, CONSTI- WATER, SUS- DATE FLTRD, FLTRD, TION FLTRD, MG/L AS UNFLTRD FLTRD, FLTRD, FLTRD, FLTRD, TUENTS FLTRD, PENDED, MG/L MG/L RATIO MG/L CACO3 MG/L MG/L MG/L MG/L MG/L MG/L TONS/D MG/L (00925) (00930) (00931) (00935) (00410) (00745) (00945) (00940) (00950) (00955) (70301) (70302) (00530) NOV 20... 13.1 19.0 .7 3.76 138 <1.0 16.7 28.3 <.1 28.8 232 9.58 <10 MAR 21... -- -- -- -- 138 -- -- -- -- -- -- -- <10 MAY 08... 10.7 17.7 .6 2.79 -- .3 13.3 24.5 .1 18.2 209 -- <10 NITRITE AMMONIA CHROM- + + BARIUM, BORON, IUM, COPPER, IRON, LEAD, NITRITE NITRATE AMMONIA ORG-N, PHOS- WATER, WATER, WATER, WATER, WATER, WATER, WATER, WATER WATER, WATER, PHORUS, ARSENIC UNFLTRD UNFLTRD CADMIUM UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD WATER, WATER RECOV- RECOV- WATER, RECOV- RECOV- RECOV- RECOV- DATE MG/L MG/L MG/L MG/L UNFLTRD UNFLTRD ERABLE, ERABLE, UNFLTRD ERABLE, ERABLE, ERABLE, ERABLE, AS N AS N AS N AS N MG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L (00615) (00630) (00610) (00625) (00665) (01002) (01007) (01022) (01027) (01034) (01042) (01045) (01051) NOV 20... .03 2.10 .02 <.20 E.16 <2 57.5 30 <.1 <.8 <10 50 <1 MAR 21... .02 2.30 .04 .40 .26 -- -- -- -- -- -- -- -- MAY 08... <.01 1.80 .02 <.20 .13 <2 57.0 30 <.1 E.5 <10 210 <1 MANGAN- PHEN- ESE, MERCURY SILVER, ZINC, OLIC WATER, WATER, SELEN- WATER, WATER, COM- UNFLTRD UNFLTRD IUM, UNFLTRD UNFLTRD CYANIDE POUNDS, MBAS, RECOV- RECOV- WATER, RECOV- RECOV- WATER WATER, WATER, DATE ERABLE, ERABLE, UNFLTRD ERABLE, ERABLE, UNFLTRD UNFLTRD UNFLTRD UG/L UG/L UG/L UG/L UG/L MG/L UG/L MG/L (01055) (71900) (01147) (01077) (01092) (00720) (32730) (38260) NOV 20... 35.1 <.01 <2 <.3 <20 <.01 E58 <.05 MAR 21... -- -- -- -- -- -- -- -- MAY 08... 33.4 <.01 <2 <.3 <20 <.01 <16 E.04 < -- Less than E -- Estimated value 195 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 Highway 2, 0.6 mi (1.0 km) downstream from Río Indio and 0.8 mi (1.3 km) east of Vega Baja. DRAINAGE AREA.--99.1 mi2 (256.7 km2), of which 25.4 mi2 (65.8 km2), does not contribute directly to surface runoff. WATER-DISCHARGE RECORDS PERIOD OF 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 OF RECORD.--Flood of December 11, 1965, reached a stage of 26.2 ft (7.99 m), datum unknown, discharge about 28,000 ft3/s (793 m3/s). Discharge, cubic feet per second WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 19 18 56 145 113 51 61 778 54 29 e26 e45 2 17 19 62 134 85 52 52 854 73 29 e44 e39 3 16 e22 137 127 77 53 72 309 95 29 44 e91 4 16 e29 273 122 145 52 48 238 83 29 36 e319 5 60 e21 525 163 83 50 104 195 68 29 28 151 6 31 e28 313 298 75 48 260 239 57 30 26 137 7 23 e41 155 330 88 46 402 175 50 42 26 59 8 20 e4010 144 179 73 69 696 171 46 32 29 48 9 91 e911 e92 146 68 60 287 128 43 28 30 42 10 80 e355 e78 128 66 51 143 114 43 28 28 38 11 190 e224 e81 119 70 70 102 104 40 28 29 36 12 56 e162 e163 111 63 64 83 104 40 143 29 34 13 38 e139 328 102 64 e60 70 87 47 195 33 33 14 192 e124 320 97 64 e55 63 83 39 54 38 36 15 351 e109 320 95 60 49 77 79 37 61 57 265 16 297 e89 285 95 57 51 369 76 35 38 32 228 17 91 e87 978 95 55 51 241 73 36 51 37 89 18 68 e83 763 101 54 52 137 69 65 35 29 125 19 54 e94 353 93 108 58 109 67 58 32 29 141 20 39 79 250 80 121 58 321 64 47 30 25 271 21 32 72 216 80 65 52 763 63 49 29 24 446 22 41 66 295 80 56 53 260 60 40 49 24 119 23 33 61 825 79 54 51 308 58 36 40 24 87 24 24 80 869 129 51 52 265 56 34 31 48 167 25 26 87 408 93 51 46 273 52 33 e29 e28 e243 26 25 67 299 79 54 42 593 49 33 e26 e26 e111 27 23 60 246 79 61 42 905 50 34 e44 e25 125 28 24 62 211 95 52 53 304 52 35 e50 e25 87 29 23 78 184 110 --- 169 192 48 32 e35 e27 86 30 23 73 166 104 --- 77 402 99 30 e28 e27 58 31 20 --- 157 146 --- 58 --- 111 --- e26 e67 --- TOTAL 2043 7350 9552 3834 2033 1795 7962 4705 1412 1359 1000 3756 MEAN 65.9 245 308 124 72.6 57.9 265 152 47.1 43.8 32.3 125 MAX 351 4010 978 330 145 169 905 854 95 195 67 446 MIN 16 18 56 79 51 42 48 48 30 26 24 33 AC-FT 4050 14580 18950 7600 4030 3560 15790 9330 2800 2700 1980 7450 CFSM 0.67 2.47 3.11 1.25 0.73 0.58 2.68 1.53 0.47 0.44 0.33 1.26 IN. 0.77 2.76 3.59 1.44 0.76 0.67 2.99 1.77 0.53 0.51 0.38 1.41 STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1973 - 2002, BY WATER YEAR (WY) MEAN 157 205 206 106 88.0 78.2 141 175 70.4 56.2 75.5 142 MAX 559 523 1316 339 190 339 667 655 239 235 461 690 (WY) 1986 1980 1982 1997 1988 1990 1987 1985 1987 1999 1979 1996 MIN 45.9 28.3 12.9 30.2 27.2 20.5 16.2 24.7 12.5 14.0 21.2 26.7 (WY) 1974 1998 1998 1995 1994 1994 1984 1977 1994 1994 1978 1994 SUMMARY STATISTICS FOR 2001 CALENDAR YEAR FOR 2002 WATER YEAR WATER YEARS 1973 - 2002 ANNUAL TOTAL 31807 46801 ANNUAL MEAN 87.1 128 124 HIGHEST ANNUAL MEAN 236 1982 LOWEST ANNUAL MEAN 38.5 1994 HIGHEST DAILY MEAN 4010 Nov 8 4010 Nov 8 14600 Dec 13 1981 LOWEST DAILY MEAN 15 Jun 12 16 Oct 3 7.2 May 3 1995 ANNUAL SEVEN-DAY MINIMUM 16 Jun 9 21 Oct 28 8.1 Apr 28 1995 MAXIMUM PEAK FLOW 2240 May 1 34000 Apr 12 1987 MAXIMUM PEAK STAGE 12.71 May 1 19.10 Apr 12 1987 INSTANTANEOUS LOW FLOW 14 Oct 3 7.2 May 2 1995 ANNUAL RUNOFF (AC-FT) 63090 92830 89760 ANNUAL RUNOFF (CFSM) 0.88 1.29 1.25 ANNUAL RUNOFF (INCHES) 11.94 17.57 16.99 10 PERCENT EXCEEDS 170 286 239 50 PERCENT EXCEEDS 34 64 57 90 PERCENT EXCEEDS 19 28 22 e Estimated 196 RIO CIBUCO BASIN 50039500 RIO CIBUCO AT VEGA BAJA, PR--Continued O N D 2001 J F M A M J J A S 2002 10 20 50 100 100 200 500 1000 1000 2000 5000 10,000 DISCHARGE, IN CUBIC FEET PER SECOND 197 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 2001 TO SEPTEMBER 2002 TURBID- FECAL FECAL SPECIF. PH, ITY, DIS- COD, COLI- STREP- HARD- INSTAN- CONDUC- WATER, WAT UNF SOLVED HIGH FORM, TOCOCCI NESS, TANEOUS TANCE, UNFLTRD TEMPER- LAB, DIS- OXYGEN, LEVEL, M-FC KF WATER, CALCIUM DIS- WAT UNF FIELD, ATURE, HACH SOLVED PERCENT WATER, 0.7U MF MF, UNFLTRD WATER, DATE TIME CHARGE, US/CM STD WATER, 2100AN OXYGEN, OF SAT- UNFLTRD COL/ COL/ MG/L AS FLTRD, CFS 25 DEGC UNITS DEG C NTU MG/L URATION MG/L 100 ML 100 ML CACO3 MG/L (00061) (00095) (00400) (00010) (99872) (00300) (00301) (00340) (31625) (31673) (00900) (00915) NOV 19... 1400 102 475 7.5 26.2 8.1 7.0 88 <10 530 730 200 66.8 MAR 06... 1100 37 445 7.7 24.5 5.0 6.9 83 <10 460 290 -- -- MAY 06... 1330 -- -- -- -- 80 -- -- <10 -- -- 160 50.3 SEP 03... 1110 185 265 6.7 26.1 300 6.0 75 10 E19000 E17000 120 37.0 ANC, RESIDUE RESIDUE WAT UNF WATER, TOTAL MAGNES- POTAS- FIXED CHLOR- FLUOR- FLTRD, AT 105 IUM, SODIUM, SODIUM SIUM, END PT, SULFIDE SULFATE IDE, IDE, SILICA, SUM OF RESIDUE DEG. C, WATER, WATER, ADSORP- WATER, FIELD, WATER WATER, WATER, WATER, WATER, CONSTI- WATER, SUS- DATE FLTRD, FLTRD, TION FLTRD, MG/L AS UNFLTRD FLTRD, FLTRD, FLTRD, FLTRD, TUENTS FLTRD, PENDED, MG/L MG/L RATIO MG/L CACO3 MG/L MG/L MG/L MG/L MG/L MG/L TONS/D MG/L (00925) (00930) (00931) (00935) (00410) (00745) (00945) (00940) (00950) (00955) (70301) (70302) (00530) NOV 19... 8.69 14.4 .4 3.16 194 <1.0 17.6 25.9 .1 17.5 271 74.6 <10 MAR 06... -- -- -- -- 174 -- -- -- -- -- -- -- <10 MAY 06... 8.15 14.4 .5 3.17 -- <.1 14.8 19.8 E.1 18.2 220 -- 50 SEP 03... 7.74 12.5 .5 2.89 93 <.1 12.0 16.1 .14 17.4 162 80.7 238 NITRITE AMMONIA CHROM- + + BARIUM, BORON, IUM, COPPER, IRON, LEAD, NITRITE NITRATE AMMONIA ORG-N, PHOS- WATER, WATER, WATER, WATER, WATER, WATER, WATER, WATER WATER, WATER, PHORUS, ARSENIC UNFLTRD UNFLTRD CADMIUM UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD WATER, WATER RECOV- RECOV- WATER, RECOV- RECOV- RECOV- RECOV- DATE MG/L MG/L MG/L MG/L UNFLTRD UNFLTRD ERABLE, ERABLE, UNFLTRD ERABLE, ERABLE, ERABLE, ERABLE, AS N AS N AS N AS N MG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L (00615) (00630) (00610) (00625) (00665) (01002) (01007) (01022) (01027) (01034) (01042) (01045) (01051) NOV 19... .02 1.50 .04 E.20 E.08 E2 57.1 30 <.1 E.5 <10 360 M MAR 06... .01 1.60 .02 <.20 .18 -- -- -- -- -- -- -- -- MAY 06... .04 1.20 .04 .60 .14 <2 56.7 20 <.1 2.4 E10 1770 1 SEP 03... .04 .960 .07 1.1 .32 <2 79.0 30 <.1 11.8 20 5810 3 MANGAN- PHEN- ESE, MERCURY SILVER, ZINC, OLIC WATER, WATER, SELEN- WATER, WATER, COM- UNFLTRD UNFLTRD IUM, UNFLTRD UNFLTRD CYANIDE POUNDS, MBAS, RECOV- RECOV- WATER, RECOV- RECOV- WATER WATER, WATER, DATE ERABLE, ERABLE, UNFLTRD ERABLE, ERABLE, UNFLTRD UNFLTRD UNFLTRD UG/L UG/L UG/L UG/L UG/L MG/L UG/L MG/L (01055) (71900) (01147) (01077) (01092) (00720) (32730) (38260) NOV 19... 47.1 <.01 <2 <.3 <20 <.01 <16 <.05 MAR 06... -- -- -- -- -- -- -- -- MAY 06... 88.4 .01 <2 <.3 <20 <.01 <16 <.05 SEP 03... 354 .03 <2 <.3 50 <.01 <16 <.05 < -- Less than E -- Estimated value 198 THIS PAGE IS INTENTIONALLY BLANK 199 Figure 16. Río de la Plata basin. 200 RIO DE LA PLATA BASIN 50039990 LAGO CARITE AT GATE TOWER NEAR CAYEY, PR 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 Hidroeléctrica de Carite Num. 1 and 1.8 mi (2.9 km) northeast from Escuela Segunda Unidad. DRAINAGE AREA.--8.20 mi2 (21.2 km2). ELEVATION RECORDS PERIOD OF RECORD.--May 1989 to current year. Prior to October 1994, published as Lago Carite at Gate Tower. 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 length 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 1,789.62 ft (545.48 m), September 21, 1998; minimum elevation, 1,761.22 ft (536.81 m), May 28, 1995. EXTREMES FOR CURRENT YEAR.--Maximum elevation 1,778.20 ft (541.99 m), September 29; minimum elevation, 1,765.88 ft (538.14 m), May 29. 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 1,746 0 1,775 6,194 1,760 2,471 1,780 7,704 1,769 4,561 1,790 11,048 Elevation above NGVD 1929, feet WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 DAILY OBSERVATION AT 2400 HOURS DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 1768.50 1770.40 1772.56 1773.43 1772.20 1770.29 1767.50 1768.18 1767.75 1776.11 1775.95 1776.66 2 1768.42 1770.33 1772.49 1773.37 1772.14 1770.20 1767.39 1768.09 1767.75 1776.12 1775.90 1776.70 3 1768.38 1770.29 1772.44 1773.32 1772.22 1770.09 1767.37 1768.00 1767.73 1776.13 1775.85 1776.71 4 1768.29 1770.26 1772.43 1773.25 1772.19 1770.00 1767.34 1767.93 1768.41 1776.13 1775.78 1776.68 5 1768.49 1770.32 1772.43 1773.24 1772.14 1769.90 1767.28 1767.87 1771.11 1776.13 1775.74 1776.65 6 1768.46 1770.51 1772.37 1773.24 1772.08 1769.80 1767.20 1767.79 1771.50 1776.17 1775.69 1776.65 7 1768.41 1770.74 1772.32 1773.18 1772.04 1769.69 1767.46 1767.74 1771.61 1776.26 1775.68 1776.63 8 1768.41 1772.86 1772.25 1773.12 1771.98 1769.66 1767.48 1767.66 1771.65 1776.26 1775.65 1776.64 9 1768.67 1773.18 1772.18 1773.06 1771.90 1769.57 1767.53 1767.59 1771.71 1776.25 1775.60 1776.63 10 1768.89 1773.25 1772.11 1772.99 1771.85 1769.46 1767.49 1767.51 1771.70 1776.23 1775.54 1776.63 11 1768.87 1773.26 1772.13 1772.93 1771.77 1769.36 1767.43 1767.43 1771.69 1776.20 1775.47 1776.54 12 1768.80 1773.25 1772.30 1772.87 1771.69 1769.27 1767.35 1767.34 1771.70 1776.18 1775.46 1776.49 13 1768.76 1773.29 1772.31 1772.80 1771.60 1769.23 1767.27 1767.24 1771.68 1776.14 1775.40 1776.46 14 1768.70 1773.29 1772.23 1772.74 1771.53 1769.11 1767.18 1767.15 1771.63 1776.35 1775.38 1776.43 15 A 1773.28 1772.26 1772.67 1771.46 1769.02 1767.20 1767.05 1771.59 1776.36 1775.36 1777.42 16 A 1773.25 1772.82 1772.60 1771.37 1768.91 1767.65 1766.96 1771.55 1776.34 1775.48 1777.61 17 A 1773.22 1772.90 1772.52 1771.30 1768.80 1767.69 1766.86 1771.69 1776.35 1775.45 1777.63 18 A 1773.20 1773.06 1772.49 1771.23 1768.71 1767.68 1766.77 1772.78 1776.32 1775.89 1777.61 19 A 1773.18 1773.32 1772.44 1771.20 1768.59 1767.64 1766.66 1772.98 1776.28 1775.88 1777.58 20 A 1773.13 1773.51 1772.37 1771.11 1768.48 1767.95 1766.56 1773.06 1776.25 1775.85 1777.57 21 A 1773.10 1773.56 1772.30 1771.01 1768.37 1768.49 1766.52 1775.18 1776.21 1775.81 1777.54 22 A 1773.04 1773.61 1772.30 1770.92 1768.24 1768.54 1766.42 1775.58 1776.17 1775.74 1777.53 23 A 1772.99 1773.68 1772.25 1770.84 1768.17 1768.51 1766.33 1775.72 1776.17 1775.71 1777.53 24 A 1772.98 1773.72 1772.24 1770.75 1768.08 1768.49 1766.23 1775.83 1776.15 1775.66 1777.98 25 A 1772.93 1773.71 1772.18 1770.66 1767.98 1768.48 1766.13 1775.91 1776.12 1775.66 1778.14 26 A 1772.88 1773.68 1772.11 1770.58 1767.84 1768.46 1766.04 1775.94 1776.06 1775.57 1778.18 27 A 1772.80 1773.65 1772.03 1770.48 1767.77 1768.42 1766.00 1776.02 1776.04 1775.51 1778.16 28 A 1772.75 1773.61 1772.21 1770.39 1767.68 1768.36 1765.98 1776.06 1776.09 1775.48 1778.14 29 1770.44 1772.70 1773.57 1772.21 --- 1767.73 1768.28 1766.21 1776.08 1776.07 1775.46 1778.13 30 1770.49 1772.62 1773.54 1772.19 --- 1767.66 1768.22 1767.60 1776.10 1776.04 1775.74 1778.14 31 1770.44 --- 1773.49 1772.18 --- 1767.56 --- 1767.69 --- 1775.99 1776.33 --- MAX --- 1773.29 1773.72 1773.43 1772.22 1770.29 1768.54 1768.18 1776.10 1776.36 1776.33 1778.18 MIN --- 1770.26 1772.11 1772.03 1770.39 1767.56 1767.18 1765.98 1767.73 1775.99 1775.36 1776.43 A No gage-height record 201 RIO DE LA PLATA BASIN 50039990 LAGO CARITE AT GATE TOWER NEAR CAYEY, PR--Continued O N D 2001 J F M A M J J A S 2002 1764 1766 1768 1770 1772 1774 1776 1778 1780 ELEVATION, IN FEET Gap indicates missing record 202 RIO DE LA PLATA BASIN 50043000 RIO DE LA PLATA AT PROYECTO LA PLATA, PR WATER-QUALITY RECORDS LOCATION.--Lat 18°09'37", long 66°13'44", Hydrologic Unit 21010005, at upstream side of bridge on Highway 173, 0.4 mi (0.6 km) northeast of Proyecto La Plata, and 2.5 mi (4.0 km) upstream from Río Usabón. DRAINAGE AREA.--63.0 mi2 (163.2 km2), excludes 8.2 mi2 (21.1 km2) upstream from Lago Carite, the flow of which is diverted to Río Guamaní. PERIOD OF RECORD.--Water years 1958 to current year. WATER-QUALITY DATA, WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 TURBID- FECAL FECAL SPECIF. PH, ITY, DIS- COD, COLI- STREP- HARD- INSTAN- CONDUC- WATER, WAT UNF SOLVED HIGH FORM, TOCOCCI NESS, TANEOUS TANCE, UNFLTRD TEMPER- LAB, DIS- OXYGEN, LEVEL, M-FC KF WATER, CALCIUM DIS- WAT UNF FIELD, ATURE, HACH SOLVED PERCENT WATER, 0.7U MF MF, UNFLTRD WATER, DATE TIME CHARGE, US/CM STD WATER, 2100AN OXYGEN, OF SAT- UNFLTRD COL/ COL/ MG/L AS FLTRD, CFS 25 DEGC UNITS DEG C NTU MG/L URATION MG/L 100 ML 100 ML CACO3 MG/L (00061) (00095) (00400) (00010) (99872) (00300) (00301) (00340) (31625) (31673) (00900) (00915) NOV 28... 1415 20 436 7.7 24.7 2.6 9.6 119 10 E118 E140 -- -- MAR 13... 0940 18 469 7.6 24.4 4.6 6.3 79 <10 360 390 -- -- SEP 04... 0935 40 242 6.7 26.8 41 7.0 88 10 280 320 87 21.3 ANC, RESIDUE RESIDUE WAT UNF WATER, TOTAL MAGNES- POTAS- FIXED CHLOR- FLUOR- FLTRD, AT 105 IUM, SODIUM, SODIUM SIUM, END PT, SULFIDE SULFATE IDE, IDE, SILICA, SUM OF RESIDUE DEG. C, WATER, WATER, ADSORP- WATER, FIELD, WATER WATER, WATER, WATER, WATER, CONSTI- WATER, SUS- DATE FLTRD, FLTRD, TION FLTRD, MG/L AS UNFLTRD FLTRD, FLTRD, FLTRD, FLTRD, TUENTS FLTRD, PENDED, MG/L MG/L RATIO MG/L CACO3 MG/L MG/L MG/L MG/L MG/L MG/L TONS/D MG/L (00925) (00930) (00931) (00935) (00410) (00745) (00945) (00940) (00950) (00955) (70301) (70302) (00530) NOV 28... -- -- -- -- 146 <1.0 -- -- -- -- -- -- <10 MAR 13... -- -- -- -- 152 -- -- -- -- -- -- -- <10 SEP 04... 8.08 19.0 .9 1.98 80 <.1 9.7 18.9 E.10 19.8 147 15.7 17 NITRITE AMMONIA CHROM- + + BARIUM, BORON, IUM, COPPER, IRON, LEAD, NITRITE NITRATE AMMONIA ORG-N, PHOS- WATER, WATER, WATER, WATER, WATER, WATER, WATER, WATER WATER, WATER, PHORUS, ARSENIC UNFLTRD UNFLTRD CADMIUM UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD UNFLTRD WATER, WATER RECOV- RECOV- WATER, RECOV- RECOV- RECOV- RECOV- DATE MG/L MG/L MG/L MG/L UNFLTRD UNFLTRD ERABLE, ERABLE, UNFLTRD ERABLE, ERABLE, ERABLE, ERABLE, AS N AS N AS N AS N MG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L UG/L (00615) (00630) (00610) (00625) (00665) (01002) (01007) (01022) (01027) (01034) (01042) (01045) (01051) NOV 28... .02 2.90 .02 E.30 E.11 -- -- -- -- -- -- -- -- MAR 13... .06 3.30 .08 .40 .20 -- -- -- -- -- -- -- -- SEP 04... .05 1.40 .04 .50 .14 <2 16.4 50 <.1 E.5 <10 850 <1 MANGAN- PHEN- ESE, MERCURY SILVER, ZINC, OLIC WATER, WATER, SELEN- WATER, WATER, COM- UNFLTRD UNFLTRD IUM, UNFLTRD UNFLTRD CYANIDE POUNDS, MBAS, RECOV- RECOV- WATER, RECOV- RECOV- WATER WATER, WATER, DATE ERABLE, ERABLE, UNFLTRD ERABLE, ERABLE, UNFLTRD UNFLTRD UNFLTRD UG/L UG/L UG/L UG/L UG/L MG/L UG/L MG/L (01055) (71900) (01147) (01077) (01092) (00720) (32730) (38260) NOV 28... -- -- -- -- -- -- <16 -- MAR 13... -- -- -- -- -- -- -- -- SEP 04... 43.5 E.01 <2 <.3 <20 <.01 <16 E.04 < -- Less than E -- Estimated value 203 RIO DE LA PLATA BASIN 50043800 RIO DE LA PLATA AT COMERIO, PR LOCATION.--Lat 18°13'23", long 66°13'30", Hydrologic Unit 21010005, on right bank 50 ft (15 m) upstream from bridge off Highway 167 in the Town of Comerío, 0.4 mi (0.6 km) southwest of Comerío High School, and 0.2 mi (0.3 km) northeast of Plaza de Comerío. DRAINAGE AREA.--109 mi2 (282 km2). WATER-DISCHARGE RECORDS PERIOD OF RECORD.--December 1988 to current year. GAGE.--Water-stage recorder and crest-stage gage. Datum of gage is 604.2 ft (184.160 m) above mean sea level. REMARKS.--Records fair. Filtration plant more or less 500 feet upstream from station. Gage-height and precipitation satellite telemetry at station. Discharge, cubic feet per second WATER YEAR OCTOBER 2001 TO SEPTEMBER 2002 DAILY MEAN VALUES DAY OCT NOV DEC JAN FEB MAR APR MAY JUN JUL AUG SEP 1 23 34 57 59 185 41 120 411 74 35 105 641 2 21 270 1150 54 124 45 173 322 47 34 80 323 3 23 1170 414 53 101 48 62 225 37 33 49 309 4 31 496 134 53 195 41 49 151 38 32 31 258 5 43 144 398 58 117 44 44 122 1690 30 29 149 6 180 248 332 154 81 41 49 92 1080 28 28 66 7 74 235 119 129 72 38 48 84 296 31 30 49 8 37 11800 84 84 64 45 227 132 142 32 31 49 9 71 3570 71 68 60 52 565 77 100 27 38 45 10 112 974 61 61 58 44 259 60 149 24 32 37 11 187 421 70 58 53 45 119 50 78 21 25 37 12 212 248 155 56 47 39 72 49 60 74 23 34 13 57 177 328 54 47 38 54 40 56 50 23 30 14 59 147 160 54 46 43 43 40 52 31 24 28 15 244 124 118 58 45 39 42 39 44 123 32 1140 16 902 231 454 55 47 36 422 37 36 84 44 2140 17 540 323 939 54 42 36 402 34 54 47 138 274 18 178 155 703 56 45 29 154 36 666 36 60 233 19 106 107 647 61 250 33 148 36 429 34 239 123 20 73 97 360 57 234 30 742 33 175 30 69 81 21 55 76 230 56 90 28 2470 32 851 28 42 105 22 43 68 246 57 57 29 615 29 1950 31 33 61 23 39 63 1030 75 49 28 383 29 235 37 29 48 24 34 66 1150 114 43 27 905 29 98 34 29 91 25 31 61 389 91 39 25 679 29 67 33 27 350 26 29 56 180 68 43 27 504 27 56 29 23 231 27 27 54 119 58 48 28 292 30 52 27 26 146 28 25 55 93 66 45 31 162 45 52 41 25 85 29 24 63 75 208 --- 734 108 55 44 75 27 76 30 28 69 69 151 --- 483 100 239 39 42 68 57 31 29 --- 63 130 --- 101 --- 188 --- 30 533 --- TOTAL 3537 21602 10398 2410 2327 2348 10012 2802 8747 1243 1992 7296 MEAN 114 720 335 77.7 83.1 75.7 334 90.4 292 40.1 64.3 243 MAX 902 11800 1150 208 250 734 2470 411 1950 123 533 2140 MIN 21 34 57 53 39 25 42 27 36 21 23 28 MED 43 146 180 58 55 39 158 45 70 33 31 88 AC-FT 7020 42850 20620 4780 4620 4660 19860 5560 17350 2470 3950 14470 CFSM 1.05 6.64 3.09 0.72 0.77 0.70 3.08 0.83 2.69 0.37 0.59 2.24 IN. 1.21 7.41 3.57 0.83 0.80 0.81 3.43 0.96 3.00 0.43 0.68 2.50 STATISTICS OF MONTHLY MEAN DATA FOR WATER YEARS 1989 - 2002, BY WATER YEAR (WY) MEAN 220 265 132 133 91.8 47.5 71.0 84.0 84.6 79.9 130 403 MAX 866 1264 457 732 268 75.7 334 263 292 291 563 1433 (WY) 1991 2000 1999 1992 1998 2002 2002 1992 2002 1993 2000 1996 MIN 40.6 19.0 17.1 21.3 24.4 20.6 22.3 19.7 13.2 10.4 12.7 26.2 (WY) 1992 1995 1995 1995 1990 1993 1991 1994 1994 1994 1994 1997 SUMMARY STATISTICS FOR 2001 CALENDAR YEAR FOR 2002 WATER YEAR WATER YEARS 1989 - 2002 ANNUAL TOTAL 51775 74714 ANNUAL MEAN 142 205 144 HIGHEST ANNUAL MEAN 267 2000 LOWEST ANNUAL MEAN 35.3 1994 HIGHEST DAILY MEAN 11800 Nov 8 11800 Nov 8 32400 Sep 10 1996 LOWEST DAILY MEAN 12 Jul 22 21 Oct 2 5.8 Jun 25 1994 ANNUAL SEVEN-DAY MINIMUM 15 Jul 18 27 Aug 23 7.3 Jul 31 1994 MAXIMUM PEAK FLOW 25600 Nov 8 127000 Jan 5 1992 MAXIMUM PEAK STAGE 15.53 Nov 29.22 Jan 5 1992 ANNUAL RUNOFF (AC-FT) 102700 148200 104200 ANNUAL RUNOFF (CFSM) 1.31 1.89 1.33 ANNUAL RUNOFF (INCHES) 17.75 25.62 18.01 10 PERCENT EXCEEDS 230 412 214 50 PERCENT EXCEEDS 34 59 42 90 PERCENT EXCEEDS 21 29 17 204 RIO DE LA PLATA BASIN 50043800 RIO DE LA PLATA AT COMERIO, PR--Continued O N D 2001 J F M A M J J A S 2002 10 20 50 100 100 200 500 1000 1000 2000 5000 10,000 10,000 20,000 50,000 100,000 DISCHARGE, IN CUBIC FEET PER SECOND 205 RIO DE LA PLATA BASIN 50043800 RIO DE LA PLATA AT COMERIO, PR--Continued WATER-QUALITY RECORDS PERIOD OF RECORD.--Water year 1989 to current year. PERIOD OF DAILY RECORD.-- SUSPENDED-SEDIMENT DISCHARGE: October 1989 to current year. INSTRUMENTATION.--USD-77 sediment sampler since 1989. Automatic sediment sampler since 1989. REMARKS.--Sediment samples were collected by a local observer on a weekly basis. During high flow events sediment samples were collected with automatic sediment sampler. EXTREMES FOR PERIOD OF DAILY RECORD.-- SEDIMENT CONCENTRATION: Maximum daily mean, 8,800 mg/L January 05, 1992; Minimum daily mean, 1 mg/L several years. SEDIMENT LOADS: Maximum daily mean, 950,000 tons (862,000 tonnes) January 05, 1992; Minimum daily mean, 0.04 tons (0.04 tonne) November 28, 1994. EXTREMES FOR WATER YEARS 2001.-- SEDIMENT CONCENTRATION: Maximun daily mean, 883 mg/L November 2, 2000; Minimun daily mean, 3 mg/L June 23, 2001. SEDIMENT LOADS: Maximun daily mean, 14,500 tons (13,154 tonnes) November 2, 2000; Minimun daily mean, 0.18 ton (0.16 tonne) June 23, 2001. EXTREMES FOR WATER YEARS 2002.-- SEDIMENT CONCENTRATION: Maximun daily mean, 2,130 mg/L November 8, 2001; Minimun daily mean, 4 mg/L January 8, 2002. SEDIMENT LOADS: Maximun daily mean, 85,300 tons (77,384 tonnes) November 8, 2001; Minimun daily mean, 0.33 ton (0.30 tonne) August 13, 2002. SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2000 TO SEPTEMBER 2001 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) OCTOBER NOVEMBER DECEMBER 1 379 109 255 2300 581 11500 317 81 76 2 1120 237 1170 3420 883 14500 111 38 12 3 1010 222 713 1000 224 669 69 28 5.3 4 311 91 80 334 94 88 56 20 3.1 5 173 54 26 180 53 26 52 19 2.6 6 121 42 14 135 42 15 49 19 2.5 7 98 31 8.2 301 65 86 50 19 2.5 8 121 32 11 391 91 101 53 19 2.7 9 282 80 67 150 55 23 55 19 2.8 10 116 38 12 109 35 10 56 19 2.9 11 88 25 6.0 93 32 8.2 55 19 2.8 12 75 24 4.8 84 30 6.8 55 19 2.8 13 90 29 7.2 102 28 7.6 57 19 2.9 14 61 20 3.3 83 25 5.7 61 19 3.2 15 62 17 2.8 79 24 5.2 90 21 5.1 16 72 18 3.4 76 24 4.9 86 23 5.4 17 136 30 24 71 23 4.5 81 25 5.5 18 210 58 42 66 23 4.1 85 30 7.3 19 414 105 306 66 22 4.0 155 50 21 20 301 87 89 63 22 3.7 126 41 15 21 126 38 14 66 21 3.8 137 46 17 22 335 81 129 84 21 4.9 223 61 61 23 573 128 331 99 22 5.8 458 111 154 24 450 124 187 76 22 4.5 146 46 19 25 140 54 21 69 23 4.2 96 34 8.9 26 123 40 13 94 23 5.9 84 27 6.1 27 88 28 6.8 82 24 5.2 77 22 4.6 28 70 26 4.9 78 24 5.0 83 21 4.7 29 96 25 6.4 66 24 4.3 58 20 3.1 30 114 34 15 74 27 5.5 52 18 2.6 31 329 83 92 --- --- --- 49 17 2.2 TOTAL 7684 --- 3664.8 9891 --- 27121.8 3182 --- 466.6 206 RIO DE LA PLATA BASIN 50043800 RIO DE LA PLATA AT COMERIO, PR--Continued SEDIMENT DISCHARGE, SUSPENDED (TONS/DAY), WATER YEAR OCTOBER 2000 TO SEPTEMBER 2001 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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 FEBRUARY MARCH 1 44 16 1.9 39 18 1.9 67 17 6.9 2 42 16 1.8 33 16 1.5 129 32 13 3 44 16 1.9 36 14 1.4 56 12 1.8 4 40 16 1.7 32 12 1.1 46 9 1.1 5 40 15 1.7 27 10 0.74 42 8 0.92 6 40 15 1.7 25 9 0.62 42 7 0.84 7 36 15 1.5 24 9 0.58 39 9 0.94 8 35 15 1.4 24 9 0.58 36 11 1.1 9 37 15 1.5 25 9 0.59 29 13 1.0 10 36 15 1.5 31 9 0.72 26 14 0.94 11 36 15 1.4 32 9 0.75 24 13 0.85 12 34 15 1.3 43 9 1.0 27 13 0.93 13 34 14 1.3 54 9 1.2 30 12 1.0 14 33 14 1.3 36 8 0.81 25 12 0.81 15 31 14 1.2 32 8 0.72 24 12 0.76 16 33 14 1.3 31 8 0.71 29 11 0.90 17 39 14 1.5 32 8 0.72 31 11 0.92 18 42 14 1.6 27 8 0.60 24 12 0.75 19 34 13 1.2 23 8 0.51 21 13 0.72 20 32 13 1.2 24 8 0.52 23 14 0.85 21 32 13 1.1 24 8 0.53 41 15 1.6 22 30 13 1.0 73 41 10 81 15 3.3 23 31 12 1.0 53 49 7.1 162 41 20 24 31 12 1.0 90 32 7.8 328 411 434 25 28 12 0.91 118 21 7.0 101 46 14 26 27 12 0.85 59 11 1.8 54 13 2.0 27 26 11 0.80 44 9 1.0 e46 e9 e1.1 28 32 11 0.97 40 10 1.0 e39 e6 e0.53 29 97 33 22 --- --- --- e34 e6 e0.53 30 370 102 145 --- --- --- 29 5 0.43 31 53 21 3.0 --- --- --- 27 6 0.45 TOTAL 1499 --- 207.53 1131 --- 53.50 1712 --- 514.97 MEAN MEAN MEAN MEAN CONCEN- SEDIMENT MEAN CONCEN- 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) APRIL MAY JUNE 1 23 14 0.85 e22 e14 e0.85 27 7 0.50 2 23 22 1.4 e21 e14 e0.85 29 6 0.47 3 25 24 1.6 e21 e14 e0.85 25 5 0.36 4 26 23 1.6 e21 e14 e0.85 22 6 0.37 5 26 23 1.6 e20 e14 e0.85 27 14 1.2 6 208 71 48 e162 e41 e20 40 72 7.8 7 63 49 8.4 e207 e71 e48 26 56 3.9 8 34 41 3.8 e98 e53 e22 24 39 2.5 9 45 35 4.3 e58 e49 e8.4 22 30 1.7 10 29 29 2.3 e38 e13 e1.4 19 24 1.3 11 e25 24 1.8 e33 e14 e1.2 17 19 0.86 12 e23 e14 e0.85 e31 e6 e0.47 18 13 0.62 13 e23 e14 e0.85 e28 e8 e0.62 18 7 0.36 14 e23 e14 e0.85 e28 e8 e0.62 18 5 0.25 15 e22 e14 e0.85 e27 e7 e0.50 18 4 0.21 16 e22 e14 e0.85 e27 e7 e0.50 19 5 0.24 17 e22 e14 e0.85 e26 e7 e0.50 25 8 0.68 18 e20 e14 e0.85 e28 e6 e0.47 70 24 5.0 19 e20 e14 e0.85 e28 e6 e0.47 33 14 1.2 20 e21 e14 e0.85 e25 e5 e0.36 23 10 0.66 21 e56 e35 e4.3 e25 e5 e0.36 20 7 0.39 22 e68 e49 e8.4 e25 e5 e0.36 18 4 0.19 23 e71 e49 e8.4 e22 e6 e0.38 19 3 0.18 24 e33 e41 e3.8 e23 e6 e0.38 21 4 0.23 25 e