USGS Water-Year Summary 2021
11022480 San Diego River at Mast Road, near Santee, CA
LOCATION - Lat 32°50'25", long 117°01'30" referenced to North American Datum of 1927, San Diego County, CA, Hydrologic Unit 18070304, in Mission San Diego Grant, near right bank, at Mast Road Bridge, 0.7 mi upstream from Old Mission Damsite, 2.8 mi west of Santee, and 14.2 mi downstream from El Capitan Reservoir.
DRAINAGE AREA - 368 mi².
- WSP 1565: 1955-56. WSP 1635: 1922, 1926 (instantaneous maximum discharge), 1927. WSP 1928: Drainage area.
PERIOD OF RECORD - May 1912 to December 1915, April 1916 to current year. Monthly discharge only for some periods and yearly estimates only for 1924-25, published in WSP-1315-B. Prior to September 1981 published as "near Santee" (station 11022500).
GAGE - Water-stage recorder. Elevation of gage is 300 ft above NGVD of 1929, from topographic map. Prior to Nov. 10, 1920, nonrecording gage at site 0.7 mi downstream at different datum. Nov. 10, 1920, to Jan. 19, 1982, at site 2.6 mi downstream at different datum.
EXTREMES OUTSIDE PERIOD OF RECORD - Maximum discharge, 70,200 ft³/s, Jan. 27, 1916, gage height, 25.1 ft, site and datum in use prior to Nov. 10, 1920, from floodmarks, based on slope-conveyance computation of peak flow.
EXTREMES FOR PERIOD OF RECORD - Maximum discharge, 45,400 ft³/s, Feb. 16, 1927, gage height, 18.1 ft, site and datum then in use, from floodmarks, on basis of slope-area measurement of peak flow; no flow for many days some years.