|Location||Regional District of Okanagan-Similkameen, British Columbia, Canada / Okanogan County, Washington, United States|
|Coordinates||49°0′1.16″N 119°26′44.13″W / 49.0003222°N 119.4455917°W|
|Basin countries||Canada, United States|
|Settlements||Osoyoos, British Columbia; Oroville, Washington|
Osoyoos Lake is a lake located in British Columbia, Canada, and Washington state of the United States. Osoyoos is derived from the word sẁiẁs meaning "narrowing of the waters" in the local Okanagan language (Syilx'tsn).
Located on the lakeshore are the town of Osoyoos, British Columbia and city of Oroville, Washington. The lake's maximum elevation is 912.78 ft (278.22 m), while its minimum elevation is 909.46 ft (277.20 m). The 62-year average discharge into the Okanogan River at Oroville is 683 cu ft/s (19.3 m3/s). Maximum discharge in 2004 was 1,340 cu ft/s (38 m3/s). Oroville's Osoyoos Lake State Park is located on its shore.
Osoyoos Lake and its outlet and primary inflow, the Okanogan River (spelled in Canada as the Okanagan River), are subject to international water-sharing agreements governed by the International Joint Commission as part of the Columbia Basin. The authority responsible for overseeing the IJC agreements is the International Osoyoos Lake Board of Control, composed of appointees from Environment Canada, the BC Ministry of Water, Land Air Protection, the US Army Corps of Engineers, the US Geological Survey, and private consultants.
Inuksuk on Osoyoos Lake shore of Sẁiẁs Provincial Park in Osoyoos, looking south with Washington state near Oroville in the distance (July 2020)
- ^ a b "Annual Report to the International Joint Commission from the International Osoyoos Lake Board of Control, 2004" (PDF). Archived from the original (PDF) on 2016-03-03. Retrieved 2008-07-12.
- ^ "Complete information for Osoyoos Lake State Park". Washington State Parks. 2009. Archived from the original on 2009-12-09. Retrieved 2009-12-10.
- Lakes of the Okanagan
- Lakes of Washington (state)
- Lakes of Okanogan County, Washington
- Regional District of Okanagan-Similkameen
- Canada–United States border
- International lakes of North America
- Washington placenames of Native American origin
- Central Washington geography stubs
- British Columbia Interior geography stubs