CKC Closure to Support King County Eastside Interceptor Repair Project

The City of Kirkland is supporting King County’s urgent repair of the Eastside Interceptor (ESI), a large regional wastewater pipeline that runs along the Cross Kirkland Corridor (CKC). A section of the pipeline has developed leaks and structural issues that require immediate attention to protect public health, the environment, and community infrastructure.

Read the staff memo from the September 16, 2025 City Council Meeting(PDF, 5MB) related to this project more information. 

Why this work is happening

City water quality testing in 2024 revealed elevated bacteria levels in Houghton B1 Stream. Further investigation confirmed that the source was a leak in the Eastside Interceptor. King County engineers also found a sag in the ESI pipe that increases the risk of structural failure. If left unaddressed, the pipeline could fail, leading to uncontrolled wastewater reaching Lake Washington.

To prevent this, King County Wastewater Treatment Division is undertaking emergency repairs. The City of Kirkland issued an Emergency Proclamation to provide flexibility and ensure swift action in response to King County’s declaration of urgency.

What the project involves

The project includes:

• Installing a temporary above-ground bypass pipeline along the CKC to divert wastewater while repairs are made.
• Repairing up to six pipe joints in the sagging section of the ESI.
• Coordinating additional work to stabilize nearby slopes and repair a City-owned piped stream culvert.

Impacts to the Cross Kirkland Corridor

• The CKC will be fully closed from NE 52nd Street to 108th Ave NE throughout the month of November. 
• The City and King County will coordinate reopening of the trail once it is deemed safe for public access.
• Detour routes are provided to help trail users navigate around the closure. See the detour map below or download it as a PDF(PDF, 8MB).

What residents need to know

• Construction started on September 29, 2025. Major work is expected to occur throughout the month of November, followed by restoration activities and demobilization in December. 
• Nearby residents may notice construction equipment, pump operations running continuously, brighter lighting and odors near the diversion location, and limited tree removal in the work zone.
• Public health officials recommend avoiding direct contact with Houghton B1 Stream or its outfall in Yarrow Bay until repairs are complete and confirmed.

Staying informed

King County is leading the repair project in close coordination with the City of Kirkland. More information about King County’s Eastside Interceptor project can be found on King County's project webpage. Updates about trail closures and detour routes will be shared on this webpage as they are finalized.