PROVISIONAL DATA SUBJECT TO REVISION

LOCATION.--Lat 43° 40'05", long 115° 43'31" (revised) (NAD83), in 
   NW1/4 NW1/4 SE1/4 sec.22, T.4 N., R.6 E., Boise County, Twin Springs quad., 
   Hydrologic Unit 17050112, Boise National Forest, on right bank 1.5 mi 
   upstream from Birch Creek, 2.6 mi upstream from maximum flow line of 
   Arrowrock Reservoir, 2.4 mi downstream from Twin Springs, 14 mi upstream 
   from Arrowrock Dam, and at mile 89.5.

DRAINAGE AREA.--831 mi2 (revised), approximately. Mean elevation, 6,350 ft.

PERIOD OF RECORD.--March 1911 to current year.

GAGE.--Elevation of gage is 3,310 ft above NGVD of 1929. March 1911 to Apr. 3, 1915, 
   nonrecording gage, Apr. 4, 1915 to Sept. 30, 1965, water-stage recorder at 
   site 0.3 mi downstream at datum 5.26 ft lower, and Oct. 1, 1965 to 
   Aug. 26, 2009, at site 0.8 mi downstream at different datum.

EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 18,800 ft3/s Dec. 23, 1964, 
   gage height, 12.20 ft, from floodmark (site and datum then in use); 
   minimum, 105 ft3/s Nov. 28, 1976, gage height, 2.64 ft; 
   minimum gage height, 1.48 ft, Dec. 6, 7, 1960 (site and datum then in use).

Current shift-adjusted rating in tab-separated format.
These are updated daily and can change often! If you use these ratings it is important that you update often so that you have the most current version.
What is a shift-adjusted rating?

Station operated in cooperation with Idaho Department of Water Resources .

Realtime Gage Height data is provided by U.S. Bureau of Reclamation telemetry.