In an effort to deter fish from entering hydroelectric turbines at the Grand Coulee Dam, the Confederated Tribes of the Colville Reservation have started a five-week study to test an underwater strobe light system.NESPELEM, Washington, US, 2001-08-23 [SolarAccess.com] In an effort to deter fish from entering hydroelectric turbines at the Grand Coulee Dam, the Confederated Tribes of the Colville Reservation have started a five-week study to test an underwater strobe light system. Scientists from the Tribe, Pacific Northwest National Laboratory, U.S. Geological Survey and the Bureau of Reclamation are conducting the work. “This is an important study for the Tribe and the entire region,” says project manager Richard LeCaire. “This project is an important first step in testing what could be an extremely effective tool for enhancing resident fish stocks without affecting power generation—both at Grand Coulee and at other dams as well.” Construction of Grand Coulee Dam in the late 1930s blocked fish runs to the Upper Columbia watershed, and efforts by the Northwest Power Planning Council and Bonneville Power Administration to mitigate losses have continued since then. One form of mitigation is resident fish programs, but prior research by the Colville Tribes estimates that 402,000 fish pass through the dam each year. Of these, 85 percent pass through the third power plant’s turbine. The system includes three powerful strobe lights manufactured by Flash Technology and loaned to the Bureau of Reclamation. These will be suspended below a barge in front of the dam’s third powerhouse. Also attached to the light array are multi/split beam hydro-acoustic transducers, which track fish movement so scientists from Pacific Northwest National Labs can observe how fish react to the strobe lights. A number of hatchery reared kokanee salmon and rainbow trout will have sonic tags surgically implanted, and these tags will be tracked by sensors near the forebay area and allow scientists to understand how resident fish specifically react to the lights. The study will run 24 hours per day, 7 days per week until mid September. Bob Johnson, the PNNL fisheries biologist leading the field tests, hopes the system will keep kokanee and rainbow trout away from the turbines, keeping them in Lake Roosevelt where they will be accessible to fishermen. The study is a collaboration by a number of organizations, including the Colville Tribes and PNNL. BPA will fund the research, while the U.S. Geological Survey, Spokane Tribe, Bureau of Reclamation and Washington State Fish & Wildlife will be involved in the strobe light study.