North Mercer Island/Enatai sewer upgrade
Project update
January 20, 2023
Construction activity in Mercer Island*
At the North Mercer Pump Station: Crews are pouring concrete for the temporary pump station. See the notification for details and what to expect .
In north-central Mercer Island: While crews work in the right-of-way, temporary signals or driveway assist devices move traffic through the work area safely. See the notification for details and what to expect .
On 90th PL SE: Crews continue installing the new sewer line. See the notification for details and what to expect .
On the I-90 Trail: Crews are installing pipe using an “open cut” trenching construction technique. The trail is closed from Shorewood Dr to SE 35th PL. The trail will remain closed around the clock until it has been repaved. Additionally, you may see crews in orange vests preparing for landscape restoration and tree replanting. See the notification for detours and what to expect .
On Southeast 35th Place: Crews are preparing to install a new sewer line that will run underneath streets and through the wooded area between 97th Ave SE and the cul-de-sac on SE 35th Pl. To support future operations, below-ground structures will be built in the cul-de-sac. Parking will be restricted with resident access maintained. See the notification for details and what to expect .
Construction activity in Bellevue*
At Enatai Beach Park and the Sweyolocken Pump Station: Crews finished installing the pipe between Enatai Beach Park and the Sweyolocken Pump Station on December 19. See the notification for details .
Recent notifications:
- Pipe installation progresses to 78th Avenue Southeast
- The North Mercer Island/Enatai construction hotline is transitioning to 425-305-3578
- Saturday work will ramp up across the project corridor
- Construction schedules often change – check our website for the most up to date information!
Construction status
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North Mercer Island project area
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Project description
With over four hundred miles of pipes moving wastewater to one of our award-winning treatment plants, King County WTD works hard to maintain our system. We inspect and monitor our regional system and update plans for needed upgrades.
King County WTD needs to replace sewer pipes that serve areas in North Mercer Island, the southwest portion of Bellevue near Enatai Beach, and the Town of Beaux Arts Village. This pipeline carries wastewater from the North Mercer Island Pump Station to the Sweyolocken Pump Station in Bellevue.
To learn more about what we are building, construction, and what to expect, click on the StoryMap below.
Schedule
Project design began in 2016 and was completed in 2021. Construction began in early 2022 and will extend until 2025. View March 2022 project newsletter for latest schedule .
Contact us
Contact Kristine Cramer, community services lead at:
NMEsewer@kingcounty.gov
206-477-5415
24-hour construction hotline:
425-305-3578
Project location
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Lets Talk Mercer Island!
The City of Mercer Island and King County are collaborating to ensure Mercer Island residents get timely, accurate construction information. In addition to the County’s website, Let’s Talk Mercer Island will feature the project with monthly updates and will monitor for resident questions and comments.
Related information
Local municipalities: