USGS Water-Year Summary 2023
12318500 KOOTENAI RIVER NR COPELAND ID
LOCATION - Lat 48°54'18", long 116°24'07" referenced to North American Datum of 1983, in NW 1/4 NE 1/4 NE 1/4 sec.13, T.64 N., R.1 W., Boundary County, ID, Hydrologic Unit 17010104,
SURFACE-WATER RECORDS
PERIOD OF RECORD - October 1927 to September 1992 (discontinued) (Elevation record prior to only to May 1929). Publish as "at Copeland" 1927-29. April 1925 to September 1927 (gage height only) as reports of Water Survey of Canada. April 2018 to present.
GAGE - Water-stage recorder and temperature sensor. Datum of gage is 1,700.00 ft above Topographic Division datum of 1928. Gage readings have been reduced to that datum. NGVD of 1929 is about 0.03 ft higher. Prior to September 30, 1975, water-stage recorder located 1 mi downstream at same datum. Oct 1927 to Nov. 20, 1929, nonrecording or recording gage at site downstream 0.2 mi; datum 40.77 ft higher Prior to April 18, 1929.
EXTREMES FOR PERIOD OF RECORD - UNREGULATED PERIOD (1929-71).--Maximum daily discharge, 124,000 ft/s May 30, 1948, maximum elevation, 1,772.55 ft, June 6, 1961; minimum daily discharge, 1,350 ft³/s Feb. 8, 1936; minimum elevation, 1,738.52, Apr. 2, 3, 1944. REGULATED PERIOD (1972-92).--Maximum daily discharge since regulation by Libby Dam, 56,700 ft³/s May 18, 1972; minimum daily discharge, 1,900 ft³/s Jan. 31, 1972.
WATER-QUALITY RECORDS
PERIOD OF RECORD - Water Temperature: July 2020 to current year.