LOCATION.--Lat 43° 35'13", long 115° 59'07"(Rev.)(NAD83), in NW1/4 NE1/4 sec.21, T.3 N., R.4 E., Boise County, Arrowrock Dam quad., Hydrologic Unit 17050112, on right bank 150 ft downstream from bridge on Boise-Arrowrock highway, 0.25 mi upstream from mouth, and 3 mi southwest of Arrowrock.

DRAINAGE AREA.--424 mi², revised.

PERIOD OF RECORD.--December 1915 to March 1955 (discontinued). October 1914 to November 1915, periodic discharge measurments only.

GAGE.--Staff gage. Datum of gage is 2,896.11 ft above mean sea level, unadjusted. Prior to July 15, 1921, staff gage at site 1,100 ft upstream at different datum. July 15 to Oct. 24, 1921, staff gage at site 400 ft upstream at datum 0.87 ft higher. Oct. 25, 2921 to Sept. 30, 1948, staff gages at site 200 ft upstream at datum 0.50 ft higher prior to Aug. 3, 1935, and at datum 0.23 ft higher thereafter.

REMARKS.--Diversions above station for irrigation of about 900 acres.

COOPERATION.--Some gage readings furnished by Water District No.12-A and US Corps of Engineers.

EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 6,610 ft³/s Apr. 8, 1943, gage height, 7.1 ft, site and datum then in use, from floodmark; minimum observed, 7.9 ft³/s Aug. 13-15, 17, 18, 1924, gage height, 0.09 ft.