LOCATION.--Lat 44° 41'23", long 114° 02'40" (NAD27) in SE1/4 NW1/4 sec.25, T.16 N., R.20 E., on Lemhi County, Ellis quad., Hydrologic Unit 17060202, on right bank on downstream side of old county road bridge approach, 0.2 mi southeast of Ellis, 10 mi northwest of May, and at mile 0.3.

DRAINAGE AREA.--830 mi², revised.

PERIOD OF RECORD.--October 1929 (monthly discharge only), November 1929 to September 1959, May 1971 to June 1972 (discontinued).

GAGE.--Nonrecording gage. Datum of gage is 4,638.29 ft above mean sea level. Prior to September 30, 1959, at slightly different locations at datum 1.34 ft lower.

REMARKS.--Diversions above station for irrigation of 27,000 acres, of which about 24,500 acres are irrigated with surface water (1971 determination).

EXTREMES FOR PERIOD OF RECORD.--Maximum discharge observed, 796 ft³/s June 8, 1957; maximum gage height observed, 5.71 ft, May 25, 1956, present datum (backwater from Salmon River); minimum discharge observed, 74 ft³/s May 19, 1955, gage height, 3.00 ft, present datum.