| NWSLI | Location Description |
| ABRP4 | CANAL AGUADILLA BELOW LAGO RAMEY AT AGUADILLA |
| ADJP4 | LAGO GARZAS NEAR ADJUNTAS 2SW |
| AGAP4 | RAMEY RESERVE CENTER RAIN GAUGE AT AGUADILLA |
| AGBP4 | CANAL MOCA (M 216) ABOVE AGUADILLA PLANT NEAR AGUADILLA |
| AGRP4 | CANAL DE AGUADILLA ABOVE LAGO RAMEY NEAR AGUADILLA 3NE |
| AIBP4 | RIO DE LA PLATA AT HIGHWAY 17 NEAR AIBONITO 3NE |
| ANAP4 | RIO CASEI ABOVE HACIENDA CASEI NEAR MAYAGUEZ 3NE |
| ANBP4 | RIO GRANDE DE ANASCO AT BARRIO GUACIO NEAR LAS MARIAS 2NW |
| ANMP4 | LAGO ANA MARIA AT HACIENDA ANA MARIA NEAR COTO LAUREL |
| ARCP4 | LAGO CAONILLAS AT DAMSITE NEAR UTUADO 3ENE |
| ARDP4 | RIO TANAMA AT CHARCO HONDO NEAR ARECIBO 4S |
| AREP4 | RIO GRANDE DE ARECIBO NEAR SAN PEDRO NEAR ARICEBO 5SSE |
| ARFP4 | RIO GRANDE DE ARECIBO AT CENTRAL CAMBALACHE NEAR ARECIBO 2SE |
| ARGP4 | LAGO DOS BOCAS AT DAMSITE NEAR UTUADO 5NNE |
| ARHP4 | RIO LIMON ABOVE LAGO DOS BOCAS 3E |
| BAUP4 | RIO BAUTA NEAR OROCOVIS 4W |
| BAYP4 | RIO DE BAYAMON NEAR BAYAMON 5S |
| BCAP4 | QUEBRADA SANTA CATALINA NEAR GUAYNABO |
| BZAP4 | JAGUEYES ABAJO RAIN GAUGE NEAR CAGUAS 5NW |
| BZBP4 | BAIROA ARRIBA RAIN GAUGE NEAR CAGUAS 4NW |
| BZCP4 | VAQUERIA EL NIMO NEAR CAGUAS 3SW |
| BZDP4 | BARRIO BEATRIZ RAIN GAUGE NEAR CAGUAS 5SW |
| CABP4 | RIO BAIROA ABOVE BAIROA NEAR CAGUAS 4E |
| CAGP4 | RIO GRANDE DE LOIZA NEAR CAGUAS 2E |
| CAHP4 | CANABONCITO RAIN GAUGE NEAR CAGUAS 6WSW |
| CAIP4 | LA PLAZA RAIN GAUGE NEAR CAGUAS 8S |
| CAKP4 | RIO TURABO ABOVE BORINQUEN NEAR CAGUAS 5S |
| CAMP4 | RIO CAGUAS AT VILLA BLANCA NEAR CAGUAS 1N |
| CAPP4 | RIO CANAS AT RIO CANAS |
| CDPP4 | CANAL DE PATILLAS AT INTAKE 113 NEAR SALINAS |
| CEIP4 | STORMWATER STATION AT NSRR NEAR CEIBA 3SE |
| CIAP4 | RIO GRANDE DE MAMATI AT CIALES 1SE |
| CIEP4 | RIO DE BAYAMON BELOW LAGO DE CUGRA NEAR CIDRA 2NW |
| CIFP4 | RIO DE BAYAMON AT ARENAS NEAR CIDRA 3E |
| CJDP4 | CANAL DE JUANA DIAZ AT PIEDRA AGUZADA NEAR JUANA DIAZ |
| CMAP4 | RIO CAMUY (HIGHWAY 488) NEAR CAMUY 7S |
| CMRP4 | REPRESA COMERIO 2 BLW COMERIO 4NNE |
| CNAP4 | RIO CANOVANAS NEAR CAMPO RICO 4.5S |
| COAP4 | RIO COAMO AT COAMO |
| COMP4 | RIO DE LA PLATA AT COMERIO |
| CORP4 | RIO CIBUCO BELOW COROZAL 1NW |
| CPFP4 | CANAL DE PATILLAS AT FOREBAY AT PATILLAS |
| CRRP4 | CABO ROJO RAWS AT LAS ARENAS |
| CRSP4 | LATERAL MSL, CANAL DE RIEGO DE LAJAS NEAR SABANA GRANDE |
| CSAP4 | CAMP SANTIAGO RAWS NEAR SALINAS |
| DAGP4 | LAGO DAGUEY ABOVE ANASCO |
| DEXP4 | FORT ALLEN RESERVE CENTER RAIN GAUGE NEAR JUANA DIAZ 2S |
| DRAP4 | LAGO DE CIDRA AT DAMSITE NEAR CIDRA 2NE |
| ELPP4 | RAIN GAUGE AT EL PORTAL IN EL YUNQUE NEAR LUNQUILLO 4SW |
| FAEP4 | RIO FAJARDO AT PARAISO NEAR FAJARDO 5SW |
| FAJP4 | RIO FAJARDO AT HIGHWAY 976 NEAR FAJARDO 3SW |
| FLAP4 | FLORIDA 7 WELL AT FLORIDA |
| GARP4 | GURABO ABAJO RAINGAUGE NEAR GURABO 5E |
| GCAP4 | GUANICA RAWS |
| GCRP4 | RIO GUAYANES AT CENTRAL ROIG NEAR YABUCOA 1N |
| GMNP4 | CANAL DE GUAMANI OESTE AT HWY 15 IN GUAYAMA |
| GRPP4 | RIO GRANDE DE PATILLAS BELOW LAGO PATILLAS NEAR PATILLAS |
| GSGP4 | RIO GUANAJIBO AT HIGHWAY 119 NEAR SAN GERMAN 1E |
| GUAP4 | RIO GUAJATACA BELOW LAGO GUAJATACA NEAR GUAJATACA |
| GUBP4 | CANAL DE DIVERSION LAGO GUAJATACA NEAR QUEBRADILLAS |
| GURP4 | RIO GURABO AT HIGHWAY 181 AT GURABO |
| GUSP4 | PUEBLITO DEL RIO RAIN GAUGE NEAR LAS PIEDRAS NEAR JUNCOS 7ENE |
| GUTP4 | RIO GURABO BELOW EL MANGO NEAR CAGUAS 6 ESE |
| GUVP4 | LAS PIEDRAS CONSTRUCTION RAIN GAUGE NEAR JUNCOS 6ESE |
| GYAP4 | RIO GUAYANILLA NEAR GUAYANILLA 2NNW |
| HORP4 | RIO GUANAJIBO AT HIGHWAY 100 NEAR HORMIGUEROS 1W |
| IANP4 | RIO INABON AT HACIENDA LA CONCORDIA NEAR PONCE 6NE |
| ISCP4 | CANAL MOCA BELOW FOREBAY NEAR ISABELLA |
| JABP4 | RAIN GAUGE AT BARRIO MAMEYES ABAJO NEAR JAYUYA 6N |
| JAMP4 | RAINGAUGE AT BARRIO COLLORES NEAR JAYUYA 3SSW |
| JAXP4 | RIO CAONILLAS AT PASO PALMA |
| JAYP4 | RIO SALIENTE AT COABEY NEAR JAYUY |
| JDCP4 | CANAL DE JUANA DIAZ AT BO. PENUELES NEAR SALINAS |
| JDZP4 | CANAL DE JUANA DIAZ AT PASO SECO NEAR SANTA ISABEL |
| JLGP4 | RIO JACAGUAS ABOVE LAGO GUAYABAL NEAR VILLALBA |
| JOBP4 | NERRS WATER QUALITY SITE AT JOBOS BAY - STATION 9 |
| JOQP4 | NERRS WATER QUALITY SITE AT JOBOS BAY IN AGUIRRE |
| JOXP4 | NERRS METEOROLOGICAL SITE JOBOS BAY IN AGUIRRE |
| JUAP4 | RIO JACAGUAS AT JUANA DIAZ |
| JUBP4 | LAGO GUAYABAL AT DAMSITE NEAR JUANA DIAZ 2NE |
| LADP4 | LAGO ADJUNTAS NEAR ADJUNTAS |
| LAFP4 | LATERAL M37L AT CANAL DE RIEGO AT SABANA GRANDE |
| LAGP4 | CANAL DE RIEGO DE LAJAS BELOW LAJAS |
| LARP4 | RIO GUAJATACA AT LARES |
| LCOP4 | LAGO COAMO NEAR LOS LLANOS |
| LCSP4 | LAGO CARITE AT SPILLWAY NEAR GUAYAMA |
| LGUP4 | LAGO GUAYO AT DAMSITE NEAR CASTANER 2N |
| LICP4 | LAGO ICACOS AT DAMSITE NEAR RIO BLANCO |
| LLUP4 | LAGO LUCHETTI AT DAMSITE NEAR YAUCO 4NNW |
| LLYP4 | RIO YAUCO ABOVE DIVERSION MONSERRATE NEAR YAUCO 1NNE |
| LOCP4 | LAGO LOCO AT DAMSITE NEAR YAUCO 3NW |
| LOEP4 | LAJAS IRRIGATION CANAL BELOW LAGO LOCO NEAR YAUCO 3NW |
| LOGP4 | RIO LOCO AT LAS LATAS NEAR LA JOYA NEAR GUANICA |
| LOPP4 | CANAL DE RIEGO DE LAJAS AT BO PALMAREJO NEAR LAJAS 1WSW |
| MANP4 | RIO GRANDE DE MANATI AT HWY 2 NEAR MANATI 2W |
| MAOP4 | MARICAO RAWS |
| MAUP4 | RIO MAUNABO AT LIZAS NEAR MAUNABO 3NW |
| MAYP4 | RIO ROSARIO NEAR HORMIGUEROS NEAR MAYAGUEZ |
| MBLP4 | CANAL MOCA BELOW HWY 112 AT ISABELA |
| MELP4 | LAGO MELANIA NEAR GUAYAMA 2WSW |
| MIRP4 | CERRO LA MIRA NEAR UTUADO RAIN |
| MJAP4 | CANAL DE RIEGO DE LAJAS ABOVE MAJINAS FILTER PLANT AT SANANA GRANDE |
| MJBP4 | CANAL DE RIEGO DE LAJAS BELOW MAJINAS FILTER PLANT AT SABANA GRANDE |
| MLRP4 | CANAL MOCA ABOVE LAGO REGULATOR AT ISABELA |
| MOCP4 | RIO CULEBRINAS AT HWY 404 NEAR MOCA 3SE |
| MODP4 | RIO CULEBRINAS AT MARGARITA DAM |
| MORP4 | RIO GRANDE DE MANATI NEAR MOROVIS 2S |
| MSAP4 | RIO MAMEYES NEAR SABANA NEAR LUQUILLO 4SW |
| NAMP4 | RIO GUADIANA AT GUADIANA NEAR NARANJITO 1E |
| NARP4 | LAGO DE LA PLATA AT DAMSITE NEAR NARANJITO 3NNE |
| NASP4 | RIO DE LA PLATA BELOW LA PLATA DAM NEAR NARANJITO 3NE |
| NGIP4 | RIO ICACOS NEAR NAGUABO 5NW |
| NGKP4 | RIO BLANCO NEAR NAGUABO 4WNW |
| OROP4 | LAGO DE MATRULLAS AT DAMSITE NEAR OROCOVIS 6SW |
| PANP4 | RIO MARIN NEAR PATILLAS |
| PARP4 | RAIN GAUGE AT B.O. MARIN NEAR PATILLAS 4N |
| PASP4 | LAGO PATILLAS AT DAMSITE NEAR PATILLAS 1NE |
| PATP4 | RIO GRANDE DE PATILLAS AT HWY 184 NEAR PATILLAS 2NW |
| PAXP4 | CANAL DE PATILLAS ABOVE GUAYAMA FILTRATION PLANT NEAR GUAYAMA 1SE |
| PBTP4 | CANAL DE PATILLAS ABOVE EL LEGADO INTAKE NEAR PATILLAS |
| PCEP4 | RIO CERRILLOS ABOVE LAGO CERRILLOS NEAR PONCE 9N |
| PCTP4 | CANAL DE PATILLAS ABOVE AES INTAKE AT GUAYAMA |
| PCXP4 | LAGO CERRILLOS AT DAMSITE NEAR PONCE 5NNE |
| PCYP4 | RIO CERRILLOS BELOW DAM NEAR PONCE 5NNE |
| PCZP4 | RIO PORTUGUES AT PARQUE CEREMONIAL TIBES NEAR PONCE |
| PIEP4 | RIO HUMACAO AT LOS PEIDROS 1S |
| PLOP4 | LAGO LOIZA AT DAMSITE NEAR TRUJILLO ALTO 2SSW |
| PRIP4 | LAGO PRIETO NEAR ADJUNTAS |
| PRNP4 | RIO PORTUGUES AT PARQUE CEREMONIAL TIBES NEAR PONCE |
| PRTP4 | RIO PORTUGUES NEAR TIBES NEAR PONCE 7N |
| QUEP4 | LAGO GUAJATACA AT DAMSITE NEAR QUEBRADILLAS |
| REGP4 | LAGO REGULADOR DE ISABELA NEAR HWy 112 NEAR MORA |
| RLCP4 | CANAL DE RIEGO DE LAJAS ABOVE LAJAS FILTER PLANT NEAR LAJAS |
| RPAP4 | LAS CURIAS RAIN GAUGE NEAR CUPEY 3SW |
| RPBP4 | QUEBRADA LAS CURIAS BELOW LAS CURIAS DAM NEAR RIO PIEDRAS 5S |
| RPCP4 | LAGO LAS CURIAS AT DAMSITE NEAR RIO PIEDRAS NEAR GUAYNABO 4ESE |
| RPEP4 | RIO PIEDRAS AT EL SENORIAL NEAR GUAYNABO 3E |
| RPOP4 | RIO PIEDRAS AT HATO REY, PR |
| SALP4 | RIO LAPA NEAR RABO DEL BUEY 6SW |
| SAMP4 | RIO MAJADA AT LA PLENA |
| SEBP4 | RIO GRANDE DE ANASCO NEAR SAN SEBASTIAN 5SW |
| SLEP4 | QUEBRADA SALVATIERRA NEAR SAN LORENZO 3WSW |
| SLGP4 | QUEBRADA BLANCA NEAR SAN LORENZO 3SSW |
| SLKP4 | RIO CAYAGUAS AT CERRO GORDO NEAR SAN LORENZO 2S |
| SLLP4 | RIO GRANDE DE LOIZA AT QUEBRADA ARENAS NEAR SAN LORENZO 7SW |
| SLMP4 | QUEBRADA ARENAS RAIN GAUGE NEAR SAN LORENZO 6S |
| SLNP4 | RIO GRANDE DE LOIZA AT HIGHWAY 183 NEAR SAN LORENZO |
| TOAP4 | RIO DE LA PLATA AT HIGHWAY 2 NEAR TOA ALTA 2NW |
| TOVP4 | RIO TOA VACA ABOVE LAGO TOA VACA 2SE |
| TOXP4 | LAGO TOA VACA AT DAMSITE NEAR VILLALBA |
| TRJP4 | QUEBRADA GRANDE AT DOS BOCAS NEAR TRUJILLO ALTO 1NE |
| TRUP4 | RIO GRANDE DE LOIZA BELOW LAGO LOIZA DAM AT TRUJILLO ALTO |
| USAP4 | RIO USABON AT HWY 162 NEAR BARRAN |
| USGP4 | BLDG 651 METEOROLOGICAL STATION AT GUAYNABO |
| UTHP4 | RIO TANAMA NEAR UTUADO 6WNW |
| UTKP4 | RAIN GAUGE AT BARRIO RONCADOR NEAR UTUADO 3W |
| UTUP4 | RIO GRANDE DE ARECIBO ABOVE UTUADO 2SW |
| UTXP4 | RIO GRANDE DE ARECIBO BELOW UTUADO 3N |
| VALP4 | RIO VALENCIANO NEAR JUNCOS 1S |
| VAMP4 | BARRIO MONTONES RAIN GUAGE NEAR JUNCOS 5S |
| VEDP4 | RIO ESPIRITU SANTO NEAR RIO GRANDE 2SE |
| VEGP4 | QUEBRADA SONADORA NEAR EL VERDE 1SE |
| VERP4 | RIO GRANDE NEAR EL VERDE NEAR RIO GRANDE 2S |
| VGBP4 | RIO CIBUCO AT VEGA BAJA |
| VIEP4 | VIEQUES RAWS NEAR ISABEL SEGUNDA 2SE |
| VILP4 | LAGO EL GUINEO AT DAMSITE NEAR VILLALBA 3NW |
| VINP4 | BARRIO APEADERO RAINGAGE NEAR VILLALBA 3NE |
| VIVP4 | LAGO VIVI NEAR UTUADO 4SSE |
| YAHP4 | LAGO YAHUECAS NEAR ADJUNTAS 6NW |
| YBUP4 | RIO GUAYANES NEAR HWY 918 NEAR YABUCOA 2WNW |