WALLA WALLA, Washington – Walla Walla’s new water-treatment system is now online following the completion of testing the plant’s new ultraviolet disinfection system.
“The new UV process replaces ozonation as the primary disinfection system for the city’s surface water plant,” Brenden Koch, communications manager for the city of Walla Walla stated in a news release.
The new system’s disinfection technology uses ultraviolet energy generated by high-intensity, medium-pressure lamps to scramble the DNA of pathogens in the incoming water, thereby deactivating them.
Located on the 500 block of Mill Creek Road, the Walla Walla Water Treatment Plant’s UV and chlorine disinfection allows the city’s water supply to meet U.S Environmental Protection Agency regulations created to reduce illness linked to microorganisms in public drinking-water systems. The plant receives water from the protected Mill Creek watershed, which is located in the Blue Mountains just over 14 miles east of Walla Walla.
“Customers may notice a slight difference in the taste of the water as we switch away from 100 percent well water and back to 100 percent surface water,” Koch said.
According to Koch, funding for the new disinfection system came from $24 million in low-interest loans from the Washington State Department of Health. Repayment of the loans will be made by water utility ratepayers. This process will save ratepayers approximately $5 million over the life of the loans versus conventional open-market loans.