If the Federal Energy Regulatory Commission deems the fish passage survival rate through the new turbine acceptable, the utility district plans to replace the remaining nine units at a rate of one per year. Replacing the Kaplan turbines with minimum gap runner turbines could increase the electrical power rating of the Wanapum Dam from 895 megawatts to 940 megawatts.
In looking at indirect mortality, Cada and ORNL colleague Mike Ryon measure something called "C-start," or burst, swimming performance, a reflex behavior typically used by fish to escape predators. In this test, uninjured Chinook salmon that have passed through the turbine are rapidly transferred to shore, where their C-start behavior is filmed in the first minutes after exposure using a high-speed camera.
"This test allows us to evaluate whether a turbine-passed fish's predator avoidance behavior is compromised compared to the behavior of unstressed control fish," Cada said. "In addition, we are testing the hypothesis that the advanced turbine induces less sub-lethal stress than the conventional turbine."
A final report for the C-start behavior study will be complete by September.
In another ORNL-led study, Environmental Sciences Division researchers Mark Bevelhimer and Marshall Adams are examining blood and gill tissue from salmon that have passed through the turbine to determine the prolonged stress response to physical trauma experienced during passage through the turbine. Results will help researchers assess the level of general stress experienced by the juvenile salmon that have passed through the turbi
Contact: Ron Walli
DOE/Oak Ridge National Laboratory