Lake Hills and NW Lake Sammamish sewer upgrade
June 29, 2021
Construction expected to begin in 2023
Due to slowdown in the permitting process, construction has been delayed. We now expect construction to begin in 2023.
Over the past year, King County worked to update the design of the sewer upgrade project to meet permitting requirements from the City of Redmond and several local, state, and federal agencies. Coordination with our partner agencies is necessary to make sure we install the new pipe in the safest way possible, limit impacts and maximize improvements for people and the environment.
We expect construction of the 4.5-mile-long project will take about three years. The entire sewer will not be under construction at once. Once we hire a contractor, we will share more detailed information about when the contractor expects to build each part of the sewer. Thank you for your continued patience.
The plan for trees
King County is committed to the environment, and construction projects are no exception. Learn more about the County’s commitment to trees in this fact sheet about the plan for trees along the future sewer route. Many plants and trees have grown up around the sewer pipe since it was installed 50 years ago. While the design team works to protect sensitive environments and trees, impacts can’t always be avoided. Our team is working with Tribes, local jurisdictions, and permitting agencies to protect the existing trees, minimize removals, and develop restoration plans.
The goal is a future tree canopy that is equal to or better than what exists today. Read more in The Plan for Trees fact sheet .
- Project Summer newsletter , August 2020
- Sammamish River Trail preliminary detour routes and restoration , April 2019
- Project Overview fact sheet (updated December 2018)
- Glossary of terms: King County Wastewater 101
- Meeting calendar for locations and meeting materials
- Project library for updates, fact sheets and environmental documents
- To sign up for project text alerts, text KING REDMONDSEWER to 468-311
The Lake Hills and NW Lake Sammamish sewer pipe has been serving Redmond and Bellevue for 50 years. The water you use travels down your drain to City sewer systems. The City’s pipes send wastewater to King County’s sewer system where it is carried to the Brightwater Treatment Facility in Woodinville for treatment.
King County is working on a project to upgrade 4.5 miles of this sewer pipe. King County will build the new pipe in trails, roads and parks in Redmond. This project is necessary to meet the needs of your growing community. Construction is expected to begin in 2023 and may impact your daily routine. When complete, the new pipe will provide sewer service for 50 years or more.