USGS Water-Year Summary 2020
11292700 Middle Fork Stanislaus River at Hells Half Acre Bridge, near Pinecrest, CA
LOCATION - Lat 38°14'50", long 120°02'01" referenced to North American Datum of 1927, in NW 1/4 NE 1/4 sec.31, T.5 N., R.18 E., Tuolumne County, CA, Hydrologic Unit 18040010, on left bank, 200 ft upstream from Donnell Powerplant, 800 ft downstream from Hells Half Acre bridge, 1.1 mi upstream from Cow Creek, and 4.7 mi northwest of Pinecrest.
DRAINAGE AREA - 287 mi².
PERIOD OF RECORD - February 1956 to current year. Prior to October 1965, published as "Middle Fork Stanislaus River at Hells Half Acre bridge."
WATER TEMPERATURE: Water years 1966-71, 1973-79.
GAGE - Water-stage recorder. Datum of gage is 3,418.31 ft above NGVD of 1929 (river-profile survey). Prior to Aug. 9, 1961, at site 1,600 ft upstream at different datum.
COOPERATION - Records, including diversion through Donnell Powerplant (station 11292610), were provided by Oakdale and South San Joaquin Irrigation District, under general supervision of the U.S. Geological Survey, in connection with Federal Energy Regulatory Commission project no. 2005.
EXTREMES OUTSIDE PERIOD OF RECORD - Maximum stage known since at least 1905, 23 ft, Dec. 23, 1955, from floodmarks, at present site, discharge, 26,600 ft³/s, by slope-area measurement.
EXTREMES FOR PERIOD OF RECORD - Maximum discharge, 24,600 ft³/s, Jan. 2, 1997, gage height, 18.02 ft, from rating curve extended above 5,200 ft³/s, on basis of slope-area measurement at gage height 12.20 ft; minimum daily, 3.3 ft³/s, Nov. 9, 10, 1957.