LOCATION.--Lat 42° 31'41", long 114° 01'04" (NAD27), in SW1/4 NE1/4 sec.29, T.10 S., R.21 E., Twin Falls County, Hydrologic Unit 17040212, Milner quad., on left bank 200 ft downstream from highway bridge at Milner, 0.4 mi downstream from Milner Dam, and at mile 638.7.

DRAINAGE AREA.--17,180 mi², approximately, excluding indeterminate nontributary area on Snake River Plain.

PERIOD OF RECORD.--May 1909 to current year. Monthly discharge only for some periods, published in WSP 1317.

REVISED RECORDS.--WSP l347: 1909-12, 1915-16, 1942-44, 1946-48.

GAGE.--Water-stage recorder. Datum of gage is 4,062.9 ft above NGVD of 1929. Prior to May 28, 1919, nonrecording gages at slightly different sites and datums.

REMARKS.--Flow regulated by American Falls Reservoir, Lake Walcott, Milner Lake, and other reservoirs having a combined usable capacity of about 4,700,000 acre-ft. The flow at this site represents combined flow to Snake River from 13087995 Snake River Gaging Station at Milner and 13087505 Lower Milner Power Plant, which began operation November 1992. Considerable water leaks into the Snake River Plain aquifer above station. Diversions above station for irrigation of about 1,990,000 acres, of which about 504,000 acres are irrigated by withdrawals from ground water, and about 436,000 acres are irrigated below station. Return flow in large part enters Snake River between Milner and King Hill stations. Prior to 1993 water year, at times, practically entire flow was diverted during irrigation season.

EXTREMES FOR PERIOD OF RECORD.-- UNREGULATED PERIOD (1909-1926): Maximum discharge prior to regulation by American Falls Dam, 40,000 ft³/s June 21, 1918, gage height, 19.9 ft, site and datum then in use; minimum daily, 8.0 ft³/s Aug. 22, 1924. REGULATED PERIOD (1927 to current year): Maximum daily discharge since regulation began in 1927, 31,200 ft³/s June 21, 1997; minimum daily, 0.16 ft³/s Oct. 23, 2008.