Sammamish Plateau Diversion

Project update

October 9, 2024

King County’s Sammamish Plateau Diversion Project has had a slight delay in scheduled work due to equipment issues. Work is expected to begin as early as Thursday, October 10 at 9 a.m. 

On Thursday morning, crews plan to begin work by closing a single lane of East Lake Sammamish Parkway Northeast near Northeast 26th Place.

During this work, the project team will be drilling along East Lake Sammamish Parkway Northeast to sample soil and install groundwater monitoring wells. This will help us better understand the conditions under the road.

This work requires temporary single-lane and turn-lane closures on East Lake Sammamish Parkway Northeast between Northeast 49th Place and Northeast Inglewood Hill Road between 9:00 a.m. and 3:00 p.m. Work hours are between 9 a.m. and 4 p.m., Monday through Friday. If you live nearby or travel through the area, you can expect minor traffic delays.

During this work, flaggers will direct travel throughout the area. The contractor will maintain local and emergency access. Flaggers will treat school buses as an emergency vehicle to reduce delays.

We expect this work to take about two to three weeks, depending on field conditions. We will send listserv updates to keep you updated on the progress once the work begins, and let you know about any changes to the project schedule.

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