USGS Water-Year Summary 2021
50027600 RIO GRANDE DE ARECIBO NEAR SAN PEDRO, PR
LOCATION - Lat 18°23'55.75", long 66°41'29.61" referenced to North American Datum of 1927, Arecibo Municipio, PR, 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 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.
PERIOD OF RECORD - February 1959 to February 1962; yearly measurements only. May 2001 to current year.
GAGE - Water-stage recorder, satellite telemetry at station. Elevation of gage is 49 ft (15 m) above National Geodetic Vertical Datum (NGVD) of 1929, from topographic map.