The U.S. Army Corps of Engineers has completed a fish collection and sorting facility on the South Fork McKenzie River just below Cougar Dam to support the recovery of endangered salmon and bull trout populations in the Willamette River basin.
Last year the Corps awarded a $9.7 million contract to Natt McDougall Company of Tualatin, Ore., to reestablish upstream fish passage at Cougar Dam for adult spring chinook and bull trout. Fisheries biologists believe that reconnecting fish to this high-quality habitat will substantially support recovery of imperiled fish populations in the Willamette River subbasin.
The facility includes a fish ladder leading from the base of the dam up to a fish collection and sorting facility. From there, adult salmon and bull trout will be loaded onto trucks for transport to release locations above Cougar Dam.
The Corps built Cougar Dam, located about 42 miles east of Eugene on the South Fork McKenzie River, in the 1960s. Original construction included both adult and juvenile fish passage facilities to help move fish past the dam. However, adult fish no longer migrated to its base due to downstream changes in river temperature resulting from the dam. The Corps abandoned the original adult and juvenile fish passage facilities because they were ineffective.
The Willamette Temperature Control Facility, completed in 2005, replicates pre-reservoir temperatures in the river below Cougar Dam to benefit fish and water quality. Today, salmon return to this area at the same time of the year that they did before dam construction.
The adult collection facility completes the Cougar component of the Willamette River Temperature Control project, which originally included temperature control at both Cougar and Blue River dams. The Corps determined in 2007 that it would defer work at Blue River and construct and operate a permanent facility at Cougar, which provides greater biological benefit at less cost.
The collection facility meets the terms and conditions of recent federally issued biological opinions that support the recovery of fish protected under the Endangered Species Act.
In February, 2009 a long-sought, and the first ever, "biological opinion" for federal multi-purpose dams in Oregon's Willamette River basin was released that outlines actions NOAA Fisheries Service says will avoid jeopardy to imperiled fish stocks and spur their recovery.
The document culminated a federal Endangered Species Act consultation process that began following the 1999 listing of Upper Willamette spring chinook salmon and steelhead stocks and Lower Columbia chinook and steelhead stocks as threatened.
A 2000 biological assessment, and a 2007 supplemental BA, determined that the "Willamette Project" adversely affects Upper Willamette River chinook and Upper Willamette River steelhead by blocking access to a large amount of their historical habitat upstream of the dams and by contributing to degradation of their remaining downstream habitat.
The 2007 BA proposed numerous actions for improving flow management; constructing, operating, and maintaining fish collection and passage facilities at priority sites above and below dams; improving management of mitigation hatcheries and carrying out a series of research, monitoring, and evaluation measures to develop appropriate actions and evaluate their effectiveness.
In the BiOp, NOAA Fisheries concludes that the Willamette chinook and steelhead would be jeopardized by the proposed action. But it adds measures beyond those proposed by the action agencies that it felt would avoid jeopardizing the survival of the listed fish.
In the document's "reasonable and prudent alternative," the agency lists additional measures to reduce the projects' effects and timelines for implementation of each action.
They include providing fish passage at three dams, temperature improvements downstream of another dam, improvements in downstream flows, screening of irrigation diversions, improving hatchery practices and facilities and habitat improvement projects.
In releasing the BiOp, NOAA listed "major" actions to help recover listed salmon and steelhead in the Willamette Basin:
-- Reduce the impacts of altered water temperatures in the North Santiam by actively managing releases from Detroit Dam and reservoir to benefit listed fish survival in 2009 and beyond;
-- Achieve long-term temperature improvements at Detroit Dam through operational changes or structural modifications by 2018.
-- Construction and operation of downstream passage facilities to safely pass emigrating listed fish at Cougar Dam by 2014, at Lookout Point Dam by 2021 and at Detroit Dam by 2023.
-- Reconstruction and operation of the collection facilities at various Willamette Project dams to facilitate safe collection and transport of listed fish for outplanting above the dams and for hatchery broodstock purposes.
-- Construction of a sorter/separator at Leaburg Dam on the McKenzie River by 2014 to create a natural fish sanctuary.