USGS Water-Year Summary 2023
11446200 Folsom Lake near Folsom, CA
LOCATION - Lat 38°42'29", long 121°09'22" referenced to North American Datum of 1927, in NW 1/4 NE 1/4 sec.24, T.10 N., R.7 E., Sacramento County, CA, Hydrologic Unit 18020111, near center of dam on American River, 0.7 mi downstream from South Fork American River, and 2.3 mi northeast of Folsom.
DRAINAGE AREA - 1,861 mi².
REVISIONS HISTORY - WSP 1931: Drainage area.
SURFACE-WATER RECORDS
PERIOD OF RECORD - February 1955 to current year. Prior to October 1959, published as "Folsom Reservoir near Folsom."
GAGE - Water-stage recorder. Datum of gage is NGVD of 1929 (levels by U.S. Bureau of Reclamation).
COOPERATION - Records provided by U.S. Bureau of Reclamation. Total evaporation provided by U.S. Bureau of Reclamation; not reviewed by U.S. Geological Survey.
EXTREMES FOR PERIOD OF RECORD - Maximum contents, 1,024,400 acre-ft, June 15, 1963, elevation, 467.23 ft; minimum since storage pool first filled, 140,600 acre-ft, Nov. 20, 21, 1977, elevation, 347.57 ft.