Passing Fish Through Hydraulic Turbines
Army Corps of Engineers, California, design, design criteria, engineering, fish passage, Francis turbine, hydraulics, hydroelectric, Kaplan turbine, mortality, prototype, prototype test, Shasta, survival, tailwater level, turbines
Journal or Book Title
Transactions of the American Fisheries Society
Beginning in 1959, the Walla Walla District, U.S. Army Corps of Engineers, under auspices of the Corps of Enginners' Fisheries Engineering Research Program, has conducted extensive tests on downstream passage of fish through hydraulic turbines, utilizing both model and prototype installations. Purposes of the test were (1) to establish design criteria for high-head Francis-type turbines that will provide optimum fish passage, and (2) to establish the best method of operating existing Kaplan- and Francis-type turbines that will provide maximum survival of fish under prevailing conditions. Tests at Allis-Chalmers' Hydraulic Laboratory, York, Pennsylvania, using 12-inch diameter model turbines, demonstrated that mortality among fish passing through a model was of appropriate magnitude to allow comparative studies of mortality in various model installations, that mortality was greatly influenced by turbine operating conditions (efficiency) and relationship of tailwater elevation to runner setting, and that increased clearances in the water passageways reduced mortality if turbine efficiency could be maintained. Prototype tests at Cushman No. 2 hydroelectric plant, Skokomish River, Washington, and Shasta hydroelectric plant on Sacramento River, California, verified model findings, with survival rates ranging from 45 to 77 percent at Cushman and reaching 91 percent in some instances at Shasta, depending upon turbine operating conditions and tailwater levels. These studies have given hope that through proper design, setting, and operation, successful fish passage through high-head turbines can be achieved.