August 15, 2023

Partnering with the Colville Tribes to Save Okanogan Steelhead

Antoine Valley Ranch
Antoine Valley Ranch
Photography | Ellen Bishop

Western Rivers Conservancy has reached the final stages of its game-changing project on Antoine Creek, a critical spawning stream for threatened summer steelhead flowing through the ancestral homelands of the Colville Tribes. The Okanogan River is a major tributary of the Upper Columbia River, and its juvenile salmon and steelhead navigate a 500-mile journey, including nine Columbia mainstem dams, to reach the Pacific. Then they do it again—upstream—to return home to spawn in streams like Antoine Creek.

Persistence clearly pays in the Okanogan, and a healthy dose of it has helped WRC and its partner, the Confederated Tribes of the Colville Reservation, bring a project that’s been years in the making to the finish line.

WRC and the Colville Tribes are on the cusp of conserving the 2,524-acre Antoine Valley Ranch, which spans 2.5 miles of Antoine Creek. WRC purchased the ranch in 2020 and transferred half of it to the Colville that year with funding from the Washington Department of Ecology’s Streamflow Restoration Program. WRC then held the second half while working for three years to secure funding and transfer it to the tribes. Thanks to an additional grant from the Streamflow Restoration Program, we are now poised to permanently protect and revive this invaluable steelhead stream.

In the coming years, the Colville plan to conduct extensive in-stream, riparian and upland restoration, benefitting the full range of species found on the ranch. Some managed grazing, away from riparian areas, will keep select portions of the ranch in operation. But the project’s greatest impact, when it comes to fish, is returning water to Antoine Creek, which for decades has run too low and warm for steelhead to survive and spawn.

Under Colville ownership, tribal fishery managers can provide flow increases of up to 95 percent in Antoine Creek, calibrated to match seasonal needs of the steelhead that spawn there. Importantly, the flow improvements in Antoine Creek will continue downstream into the Okanagan River, carrying their benefits even further into the Upper Columbia system.

The keystone of restoring stream-flows to Antoine Creek is—paradoxically—an earthen dam high in the system, which the Colville Tribes can now manage as a tool to deliver more water for steelhead. The old diversion dam sits upstream of natural barriers to steelhead, so left in place, tribal fish managers can now use it to strategically pulse cold flows downstream when fish need water the most, without ever obstructing migration.

The Antoine Creek project should pay huge dividends among the lands, waters and tribal culture of the Okanogan River Valley and beyond for generations. WRC and the Colville Tribe’s innovative and even unconventional solution—using a dam designed to take water out of the creek as a tool for putting water back into it—confirm our belief that creativity, perseverance and great partners can deliver real, lasting results for fish and wildlife.

Stay on top of our work

Choose the news you want to receive, and we’ll keep you abreast of our conservation efforts around the West.