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Project update

December 2022

Major construction expected to begin in 2024

King County plans to begin work to upgrade one mile of aging sewer pipe in Seattle’s Interbay neighborhood in 2024. Previously, construction was estimated to begin in mid-2022. The County pushed construction out to allow more time to acquire the necessary permits to complete the work.

King County expects to hire a contractor as early as Fall 2023. Major construction, including excavation, pipe installation, and pipe relining, will begin as soon as January 2024 and ramp up during the summer months through early fall 2024. After we hire a contractor, we will be in touch with more information on what you can expect during pre-construction and major construction.

Project description

King County plans to upgrade an aging sewer pipe in Seattle’s Interbay neighborhood. The existing pipe was built in 1967 and is nearing the end of its service life. New odor control technology will be added to the system while the sewer pipe upgrade is underway. When complete, the sewer will provide reliable service for another 50 years or more.

project site map

Project Timeline for Full Project

Project timeline for the Interbay Sewer and Odor Control Upgrade

planning phase

Contact us

Contact Ryan Harlow at:

If you’d like to receive email or text updates on the Interbay sewer and odor control upgrade:

Project location

Interbay-Sewer-location-mapView higher resolution version.

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