Operators at King County’s West Point Treatment Plant credit the new onsite battery system for providing reliable power during its first year of service, ensuring critical pumps operated during 78 power disruptions.

Engineers estimate that 15 of those power disruptions were severe enough to potentially cause an emergency bypass of untreated wastewater into Puget Sound had the onsite batteries not been activated in June 2024. Pumps at the state’s largest treatment plant were powered exclusively by the 16.8-megawatt battery system during each of those disruptions.

King County Executive Shannon Braddock praised the West Point employees who successfully built and are now operating this first-of-its-kind battery power system.

“What began as an award-winning engineering marvel is now an operational success,” said Executive Braddock. “The onsite battery system we installed at West Point Treatment Plant is delivering exactly what we promised: providing reliable power that protects Puget Sound, even when our region experiences catastrophic weather events.” Read more.