USGS Water-Year Summary 2020
11181000 San Lorenzo Creek at Hayward, CA
LOCATION - Lat 37°41'08", long 122°03'48" referenced to North American Datum of 1927, Alameda County, CA, Hydrologic Unit 18050004, in San Lorenzo Grant, on left bank, 300 ft downstream of Center Street Bridge, just outside city limits of Hayward, 0.6 mi downstream from Crow Creek, and 1.0 mi downstream from Don Castro Dam.
DRAINAGE AREA - 37.5 mi².
- WSP 1315-B: 1947 (instantaneous maximum discharge), 1949 (instantaneous maximum discharge). WSP 1345: 1940 (instantaneous maximum discharge). WSP 1715: 1947.
PERIOD OF RECORD - January 1940 to September 1940, October 1946 to April 1983, October 1997 to current year. Monthly discharge only for some periods, published in WSP 1315-B.
GAGE - Water-stage recorder and crest-stage gage. Datum of gage is 135.85 ft above NAVD of 1988 and 133.16 ft above NGVD of 1929. January to September 1940, nonrecording gage on bridge 0.1 mi upstream at present datum.
EXTREMES FOR PERIOD OF RECORD - Maximum discharge, 8,140 ft³/s, Feb. 3, 1998, gage height, 21.85 ft; no flow at times.