USGS Water-Year Summary 2023
11525400 Trinity Lake near Lewiston, CA
LOCATION - Lat 40°48'05", long 122°45'44" referenced to North American Datum of 1927, in NW 1/4 SW 1/4 sec.15, T.34 N., R.8 W., Trinity County, CA, Hydrologic Unit 18010211, Trinity National Forest, Whiskeytown-Shasta-Trinity National Recreation Area, on side of intake structure of Trinity Dam on Trinity River, and 9 mi north of Lewiston.
DRAINAGE AREA - 692 mi².
SURFACE-WATER RECORDS
PERIOD OF RECORD - November 1960 to current year. From October 1963 to September 1997 published as "Clair Engle Lake near Lewiston".
GAGE - Water-stage recorder. Datum of gage is NGVD of 1929 (levels by U.S. Bureau of Reclamation). Prior to Jan. 4, 1962, nonrecording gage at same site and datum. Contents based on capacity table provided by U.S. Bureau of Reclamation, dated April 1962.
COOPERATION - Records were provided by U.S. Bureau of Reclamation, not rounded to U.S. Geological Survey standards.
EXTREMES FOR PERIOD OF RECORD - (at 2400 hours) Maximum contents, 2,588,000 acre-ft, Jan. 19, 1974, elevation, 2,378.32 ft; minimum since first filling, 222,400 acre-ft, Nov. 9, 1977, elevation, 2,120.22 ft.