USGS Water-Year Summary 2024

13087995 SNAKE RIVER GAGING STATION AT MILNER, ID

LOCATION - Lat 42°31'41", long 114°01'06" referenced to North American Datum of 1983, in sec.29, T.10 S., R.21 E., Twin Falls County, ID, 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, excluding indeterminate nontributary area on Snake River Plain.

SURFACE-WATER RECORDS

PERIOD OF RECORD - November 1992 to current year (see REMARKS).

GAGE - Water-stage recorder and crest-stage gage. Datum of gage is 4,065.75 feet above NAVD 1988 (USGS).

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 discharge to Snake River passing through Milner Dam. Former station number for this gaging station, 13088000, represents combined flow to Snake River from this site and from 13087505 Lower Milner Power Plant, which began operation in 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 groundwater, 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 - Maximum discharge, 26,300 ft³/s June 22, 1997, gage height, 21.14 ft; minimum daily, 0.00 ft³/s on many days.