USGS Water-Year Summary 2021
11078000 Santa Ana River at Santa Ana, CA
LOCATION - Lat 33°45'04", long 117°54'27" referenced to North American Datum of 1927, in NW 1/4 SE 1/4 sec.10, T.5 S., R.10 W., Orange County, CA, Hydrologic Unit 18070203, on right bank, 850 ft upstream from Fifth Street Bridge in Santa Ana, and 1.6 mi downstream from Santiago Creek.
DRAINAGE AREA - 1,700 mi². excludes 768 mi² above Lake Elsinore.
- WSP 1635: 1940 (instantaneous maximum discharge), 1944. WDR CA-74-1: Drainage area. WDR CA-79-1: 1978 (instantaneous maximum discharge).
PERIOD OF RECORD - January 1923 to September 1989, October 1990 to current year. Discharge measurements only, October 1989 to September 1990.
GAGE - Water-stage recorder and concrete-lined flood-control channel. Elevation of gage is 70 ft above NGVD of 1929, from topographic map. October 1990 to Feb. 12, 1991, at site 900 ft downstream at different datum. Feb. 13, 1991, to Apr. 4, 1994, at datum 3 ft lower. See WDR CA-90-1 for complete history of location and datum changes.
EXTREMES FOR PERIOD OF RECORD - Maximum discharge, 46,300 ft³/s, Mar. 3, 1938, gage height, 10.20 ft, site and datum then in use, on basis of slope-area measurement of peak flow; no flow for many days each year.
PERIOD OF RECORD
DISCRETE WATER-QUALITY DATA:
CHEMICAL DATA: Water year 1998.
SEDIMENT DATA: Water years 1968-2003.
CONTINUOUS WATER-QUALITY DATA:
WATER TEMPERATURE: Water years 1969, 1971, 1973-1979, 1982-1987.
SEDIMENT DATA: Water years 1968-1971, 1973-1980, 1982-1987, 1989.