Trap-and-haul project gives Okanagan sockeye a boost during drought years

WENATCHEE — Adult sockeye salmon migrating to Canada’s Okanagan River Basin may have a better chance of surviving drought conditions after a cross-border trap-and-haul pilot project carried out this summer by Grant County Public Utility District, Chelan County Public Utility District and the Okanagan Nation Alliance.

The project, conducted July 16, was designed to mitigate the “thermal barrier” that develops when high water temperatures in the Okanogan River meet the colder Columbia River. Elevated temperatures often cause sockeye to pause or halt their migration, increasing the risk of death before spawning.

“Obtaining the necessary approvals for this pilot was a complex process, but it shows what’s possible when agencies on both sides of the border work together with a shared commitment to restoring Okanagan Sockeye,” said Catherine Willard, senior fisheries biologist with Chelan PUD.

Tom Dresser, Grant PUD’s manager of Fish, Wildlife and Water Quality, said the effort underscores the benefits of long-standing collaboration. “This pilot study illustrates the strong partnership and commitment that has been forged among Chelan PUD, Grant PUD and the Okanagan Nation Alliance to restore sockeye populations to the Okanagan River Basin. We’re seeing the results of that collaboration,” he said.

During the pilot, 105 adult sockeye were trapped at Douglas County PUD’s Wells Dam and transported by tank truck across the Canadian border to the Okanagan Nation Alliance’s kł cp̓əlk̓ stim̓ Sockeye Hatchery near Penticton, British Columbia, for spawning. The project demonstrated that the trap-and-haul method can bypass the thermal barrier and secure enough broodstock to sustain hatchery production.

The Okanogan River, spelled “Okanagan” in Canada, is the salmon’s only natural route into Canadian spawning grounds from the Upper Columbia River. No fish passage exists at Chief Joseph and Grand Coulee dams, both upstream of Wells Dam.

Efforts to restore sockeye to the basin began in the early 2000s with fry releases into Skaha Lake in Canada, followed by projects to improve flows, restore habitat and remove barriers. Grant and Chelan PUDs funded the construction and operation of the hatchery to meet fish-survival requirements of their dam licenses. The hatchery currently has the capacity to rear up to 5 million sockeye, with potential upgrades to increase capacity to 8 million. Agreements with the Okanagan Nation Alliance extend funding and monitoring through 2060.

Other collaborators on the pilot included the Washington Department of Fish and Wildlife, U.S. Department of Agriculture and the Canadian Food Inspection Agency.