Published on July 24, 2026
The treated water distributed to our customers remains safe to drink. Our water plant operators are adjusting ozone levels and making other changes to address the taste and odor concerns reported by some of our customers.
Changes in water quality in Lake Washington, including the presence of algae on the lake, have contributed to the changes in taste and odor. Our operators are aware of these changes and are continually adjusting our treatment process to resolve issues with taste and odor.
We do extensive testing of the water coming into our treatment plant and at multiple points throughout the distribution system to confirm it remains safe as it moves through the system. The city is required to regularly adjust the treatment process as necessary to match the quality of the raw water and to meet strict water quality permit requirements to ensure the safety of the water for our customers. Results for cyanotoxins testing in the distribution system were non-detect.