The Current of Innovation
PrintNew Hydropower Turbines Generate More Electricity & Help Fish
By K.C. Mehaffey
The Columbia Basin dams have withstood the test of time, bringing clean, reliable energy to homes and businesses for generations. Behind these powerhouses are highly trained U.S. Army Corps of Engineers employees who implement cutting-edge technology to adapt to the growing electricity demand in the Pacific Northwest.
A turbine replacement project at Ice Harbor Dam on the lower Snake River combined efficiency, increased energy production, and fish protection with state-of-the-art turbine design. The project generates more carbon-free power using the same amount of water to energize thousands of homes.
The multiyear project to replace Ice Harbor Dam’s 3 massive turbines is nearing completion. By this time next year, the final turbine will be installed and online.
When all 3 turbines are operational, the dam will have the potential to produce an additional 30 to 44 gigawatt-hours annually, assuming additional projects are completed at the plant, says Rachel Dibble, Bonneville Power Administration’s vice president of generation asset management.
BPA is the ratepayer-funded federal agency that supplies power to many electric cooperatives and public utility districts throughout the Pacific Northwest. Most of that power comes from dams in the Columbia Basin—including Ice Harbor Dam.
Ice Harbor Dam was built by the U.S. Army Corps of Engineers in the late 1950s, and its first turbine units started operating in 1961. In addition to the dam and powerhouse, the facility includes a spillway, navigation lock, 2 fish ladders, a removable spillway weir, and a juvenile fish bypass facility.
In 2022, after the first new turbine was installed and tested, the Corps reported increased efficiency of 3-4%, and juvenile salmon that passed through the turbine had a direct survival rate of more than 98%. The second installed turbine— which has an adjustable blade design instead of a fixed blade—tested with a fish passage survival rate of nearly 97%.
To come up with the design, the Corps’ Walla Walla District collaborated with the Hydroelectric Design Center and the Engineering Research and Design Center. The process combined the Corps’ fish passage design and modeling expertise with Voith Hydro Inc.’s experience in manufacturing hydroelectric turbines. The new turbine design streamlines water flow, resulting in safer passage for fish and more efficient generation.
In addition to increased efficiency, the new turbines reduce maintenance costs, says Dylan Peters, public affairs specialist at the U.S. Army Corps of Engineers’ Walla Walla District.
“Due to their materials and construction, these turbines are more resistant to corrosion and cavitation,” Dylan says.
The Ice Harbor Dam turbine replacement’s success leads the way for efficiency projects at other dams in the Columbia Basin. Many hydroelectric facilities in the area are more than 50 years old and have turbines approaching their life expectancy.
Dylan says the Corps plans to replace all 14 turbine units at McNary Dam on the lower Columbia River. Turbine replacement is also under consideration at other Columbia Basin dams.
“As the United States’ premier civil works and engineering organization, USACE is constantly assessing how to improve our projects and the services they deliver to the nation,” Dylan says.
