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Water-Year Summary for Site 11525400

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Available Parameters
00054 Reservoir storage(Obs.)  

Water year 2020: 2020-10-01 to 2021-09-30

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USGS Water-Year Summary 2020
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.
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.
REMARKS - Lake is formed by an earth-fill dam completed in November 1960. Storage began Nov. 23, 1960. Usable capacity, 2,437,700 acre-ft, between elevations 1,995.5 ft, elevation of invert of river outlets, and 2,370.0 ft, crest of glory hole spillway. Dead storage, 10,000 acre-ft. Operating pool is from elevation 2,145.0 ft, capacity, 312,621 acre-ft, to 2,370.0 ft, capacity, 2,447,700 acre-ft. Figures given represent total contents at 2400 hours. Lake is used for power generation, flood control, and recreation. See schematic diagram of Klamath River and Trinity River Basins available from the California Water Science Center.
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.