USGS Water-Year Summary 2025

11295230 Beaver Creek below Diversion Dam, near Arnold, CA

LOCATION - Lat 38°13'59", long 120°16'46" referenced to North American Datum of 1927, in NW 1/4 NW 1/4 sec.01, T.4 N., R.15 E., Tuolumne County, CA, Hydrologic Unit 18040010, in Stanislaus National Forest, at Beaver Creek Diversion Dam, and 4.5 mi east-southeast of Arnold.

DRAINAGE AREA - 29.3 mi².

REVISIONS HISTORY - WDR CA-92-3: 1991 (instantaneous maximum discharge).

SURFACE-WATER RECORDS

PERIOD OF RECORD - February 1990 to current year.

GAGE - Acoustic-velocity meter on low-flow discharge, and water-stage recorder on Beaver Creek Diversion Reservoir (station 11295220). Datum of gage is NGVD of 1929 (levels by Calaveras County Water District).

COOPERATION - Records were collected by Northern California Power Agency, under general supervision of the U.S. Geological Survey, in connection with Federal Energy Regulatory Commission project no. 2409.

REMARKS - Entire flow of Beaver Creek in excess of 16.5 ft³/s required for stream maintenance can be diverted through tunnel and penstock to turbine at McKays Point Reservoir (station 11295260). Capacity of tunnel and penstock is 400 ft³/s and flow in excess of that amount is either released or spilled at Beaver Creek Diversion Dam to the creek. Discharge, including extremes, represents the combined flow of Beaver Creek and spill or release at diversion dam. See schematic diagram of Stanislaus River Basin available from the California Water Science Center.

EXTREMES FOR PERIOD OF RECORD - Maximum discharge, 6,020 ft³/s, Jan. 1, 1997; minimum daily, 0.48 ft³/s, estimated, Sept. 30, 2015.