Heavy lift: Massive, aging turbine shutoff valve replaced at Round Butte hydro dam; two more to go in complex project
MADRAS, Ore. (KTVZ) -- Portland General Electric and The Confederated Tribes of Warm Springs said Thursday they are undertaking a complex project to replace the original turbine shutoff valves at their jointly owned Round Butte Hydroelectric Facility.
"This critical infrastructure upgrade demonstrates PGE's and CTWS’s commitment to maintaining reliable, clean hydroelectric power generation while supporting the continued safe operation of this critical regional resource," the two organizations said in a joint news release that continues below:
"These are the original turbine shut off valves that were installed when the facility was first built in 1964," said Jordan Messinger, PGE's principal project manager. "After more than six decades of reliable service, we are replacing the valves to support the facility's continued safe and efficient operation for decades to come."
Located about eight miles southwest of Madras, the Round Butte facility forms Lake Billy Chinook with its 440-foot-tall earthen dam. The powerhouse contains three Francis turbine units with a combined capacity of 350 megawatts and supplies water to the Deschutes River.
The 140 ton, 15-foot-wide turbine shutoff valves are the primary safety mechanism for controlling water flow to the turbines. These critical components enable emergency shut off capabilities and make it possible for operators to let water out of the turbines during maintenance operations.
The project's journey began in early 2019 with initial funding and the selection of an engineering consultant. Phase 1 of construction kicked off this July, and Messinger said the replacement project should be completed by February.
Next July, the team will begin installing the other two turbine shutoff valves, and that will be completed the following February. The project budget is about $55 million.
"We've assembled a team of specialized engineers and industry professionals with the expertise needed to handle every aspect of this project," said Messinger. "From installation to operation, we're going to make sure everything we do meets our rigorous standards for safety and reliability."
Messinger and his team have overcome several significant challenges in the years leading up to construction. First and foremost are the valves themselves – the valve body and disc alone weigh about 140 tons and must be lowered into the powerhouse as a single unit. When fully installed, the total system weight reaches about 250 tons.
Another challenge is an incredibly limited pool of global manufacturers capable of designing and fabricating valves of this size. It took two years to design, fabricate and test the new valves in Europe before they could be transported to the dam.
Despite the challenges, Messinger and his team successfully installed the first of three turbine shutoff valves in November.
“This upgrade represents a significant investment in PGE's renewable generation resources and the local economy,” said Messinger. “Together with CTWS, we're supporting native fish populations through science-backed initiatives, providing clean electricity to over 150,000 homes, and maintaining a certified low-impact facility that employs 33 local residents across central Oregon communities.”
With a 60-year lifespan, these new valves will help lower operations and maintenance costs – savings that will benefit all PGE customers – while enabling Round Butte Dam to continue generating carbon-free energy well into the future.
