USGS Water-Year Summary 2024
08131200 Twin Buttes Reservoir near San Angelo, TX
LOCATION - Lat 31°22'55", long 100°32'17" referenced to North American Datum of 1927, Tom Green County, TX, Hydrologic Unit 12090102, in outlet control tower near left end of Twin Buttes Dam on Middle Concho River, Spring Creek, and South Concho River, 3.8 mi upstream from Lake Nasworthy Dam, 8.1 mi southwest of San Angelo, and 75.0 mi upstream from mouth.
DRAINAGE AREA - 3,868 mi² of which 1,055 mi² probably is noncontributing.
REVISIONS HISTORY - WDR TX-81-3: Drainage area.
SURFACE-WATER RECORDS
PERIOD OF RECORD - Oct. 1962 to Sept. 2003 (contents), Oct. 2003 to current year.
PERIOD OF RECORD, Water-Quality.--
CHEMICAL DATA: May 1965 to Nov. 1966 and July 1970 to Apr. 1984.
BIOCHEMICAL DATA: May 1965 to Nov. 1966 and July 1970 to Oct. 1973.
GAGE - Water-stage recorder and nonrecording gage on Middle Concho-Spring Creek pool and nonrecording gage on South Concho pool. Datum of gage is NGVD of 1929. To obtain elevations in NAVD88 add 0.48 ft. to NGVD29 values. Satellite telemeter at station.
COOPERATION - Texas Water Development Board (TWDB).
EXTREMES FOR PERIOD OF RECORD - Maximum contents, 205,200 acre-ft, May 12, 1975, elevation, 1,942.20 ft; minimum since first appreciable storage (period of daily mean contents), 2,120 acre-ft, Apr. 15, 1971. Minimum elevation, 1881.03 ft., Nov. 09, 2013.