King County Sewerline Upgrade

North Mercer - Enatai Sewer Upgrade Project

King County is upgrading four miles of sewer pipeline across north Mercer Island and south Bellevue. In addition to the new sewer pipeline, King County will upgrade the County’s North Mercer Pump Station, as well as the City of Mercer Island’s Lift Station 11 at Fruitland Landing. The pipes, installed in the 1970s, are aging and reaching capacity. They serve north Mercer Island, southwest Bellevue near Enatai Beach Park, and the town of Beaux Arts. (Click map for a larger version)

The sewer upgrade is a big project that’s been years in the making and will involve years of construction. We expect construction to begin in early 2022 and be complete in 2025. Some of the work will be in heavily used public spaces, and some will be in residential areas. The end product will provide great public benefit, but the work to get there will involve inconveniences to residents and users of public spaces. The City of Mercer Island and King County are committed to keeping you informed about what’s happening and why.

Get a visual look at the project by taking an interactive tour online.

To learn more or get the latest updates on this project, visit King County’s website: www.kingcounty.gov/mercerenataisewer

If you have specific questions or concerns about this project, contact the County’s community services leads by email: NMEsewer@kingcounty.gov. For urgent issues or emergencies, contact the 24-hour construction hotline: 425-305-3578.