Department of Ecology News Release - August 29, 2016

Canada releases pulse flows to the Okanagan River

OROVILLE – Dam operators in Penticton, British Columbia are raising flows in the Okanagan River to improve conditions for salmon in Lake Osoyoos.

Beginning Aug. 29 and continuing for approximately eight days, Canadian authorities will be ramping up flows from Lake Okanagan from current late summer levels to about 1,250 cubic feet per second.

According to the Washington Department of Ecology, which manages Osoyoos Lake levels at Zosel Dam, recent flows in the Okanogan River at Oroville have been typically low for late summer, at about 250 cubic feet per second. These flows will rise over the next several days to over 1,000 cubic feet per second as more water is released from Lake Okanagan. This “pulse” is planned to last for just over a week, after which the river will subside to its usual low conditions for late summer.

During this pulse, residents at Osoyoos Lake can expect to see the lake rise about 3 to 4 inches as dam operators work to “feather” increases in flows in the river below Oroville so as to not put too much water into the river suddenly. You can watch this work develop by watching the river gauge at Oroville at

Osoyoos Lake levels are mandated by the International Joint Commission, a board made up of representatives from the United States and Canada. Ecology’s target is to maintain Osoyoos Lake at a level of between 911.5 and 911.8 feet until Sept. 15. After that, the lake will slowly be brought down to winter operations by November.

More information on the International Osoyoos Lake Board of Control can be found at

To track the progress of lake levels in “real-time,” as well as find additional information, go to the U.S. Geological Survey web page for Osoyoos Lake.


Joye Redfield-Wilder, communications, 509-575-2610; @ecyCentral