USGS Water-Year Summary 2020
12439500 OKANOGAN RIVER AT OROVILLE, WA
LOCATION - Lat 48°55'51", long 119°25'09" referenced to North American Datum of 1927, in SE 1/4 SW 1/4 sec.27, T.40 N., R.27 E., Okanogan County, WA, Hydrologic Unit 17020006, base gage on left bank in Oroville, 20 ft downstream from Burlington Northern trestle, 0.5 mi downstream from Tonasket Creek, 1.7 mi downstream from Osoyoos Lake, 3.2 mi upstream from Similkameen River, and at mile 77.3. The auxillary gage is located 0.5 mi downstream at mile 76.8.
DRAINAGE AREA - 3,195 mi².
- WDR WA-75-1: Drainage area.
PERIOD OF RECORD - October 1942 to current year.
GAGE - Water-stage recorder. Datum of gage is NGVD of 1929. Prior to Oct. 26, 1944, nonrecording gage at Zosel Mill dam 200 ft upstream, Oct. 26, 1944, to Mar. 6, 1948, water-stage recorder on railroad trestle 20 ft upstream, both at same datum. Auxiliary water-stage recorder 0.5 mi downstream used during high-water periods; May 15, 1946, to Apr. 9, 1948, nonrecording gage at same site, both at datum 900.00 ft above NGVD of 1929. To convert to 1947 joint adjustment of U.S. Coast and Geodetic Survey and Geodetic Survey of Canada, subtract 0.26 ft.
COOPERATION - This station is maintained by the United States under agreement with Canada.
EXTREMES FOR PERIOD OF RECORD - Maximum discharge, 4,340 ft³/s May 13, 2018; maximum elevation, 916.89 ft June 2, 1972, at datum then in use, backwater from Similkameen River; minimum daily discharge, -2,270 ft³/s reverse flow May 29, 1948; minimum elevation, 903.98 ft Mar. 1, 1948, at datum then in use.
PERIOD OF DAILY RECORD - WATER TEMPERATURE: April 1986 to September 1987 (at base gage), March 2005 to July 2007 (at auxiliary gage), July 2007 to current year (at base gage).
INSTRUMENTATION - Water temperature recorder with 15-minute logging interval since March, 2005.
EXTREMES FOR PERIOD OF DAILY RECORD - WATER TEMPERATURE: Maximum, 30.1°C, July 23, 2006; minimum, 0.0°C, occurs during most winters.