High inflows into Lake Okanagan are impacting flows in the Okanogan
OROVILLE – Water levels in Osoyoos Lake are rising as Canadian water managers in Penticton continue to release water from Lake Okanagan to prepare for expected high inflows into the lake from melting snows later this year.
Lake Osoyoos is fed by Canada’s Okanagan Lake to the north. Lake levels are regulated at Zosel Dam, which is managed by the Washington Department of Ecology. Operational activities on the Okanagan river system in British Columbia influence Osoyoos water levels, and making room for snow runoff in the upper watershed puts pressure on Lake Osoyoos.
“Once the Zosel Dam gates are wide open, as they are right now, Lake Osoyoos must seek its own level when runoff is high throughout the system,” according to Al Josephy, with Ecology’s water resources program.
With greater than 100 percent of average snow levels reported in all watersheds in the region, Ecology intends to manage to the usual summer target level at the Lake of between 911.5 and 912 feet from May 1 to Sept. 15.
“We’ll continue to coordinate with our Canadian partners in managing our end of the system as the spring weather progresses,” Josephy said. “This can cause inconvenience and occasional flooding to property owners along the lake and down the river itself.”
Lake levels are mandated by the International Joint Commission (IJC), a board made up of representatives from the United States and Canada. Osoyoos Lake is a source of irrigation water and summer recreation in both the U.S. and Canada.