Tunnel prep for Ship Canal Water Quality project is underway

The project to clean up water in the Ship Canal is moving to the next phase: tunnel construction preparation.

Ballard will be home to the western end of the 2.7-mile, 18-foot-wide tunnel that will extend from Wallingford to collect stormwater runoff. The Ballard site, located at 24th Ave NW and NW 54th St, will also include above-ground facilities that will support the tunnel. Tunnel boring will start at this site and move toward Fremont and Wallingford as the project continues.

This month, crews will begin building the vertical access shaft to prepare for tunnel construction in 2021. According to Seattle Public Utilities, for the next few months, crews will be:

• Installing a 12’ high sound containment wall to help mitigate construction noise
• Installing stormwater controls
• Installing dewatering equipment
• Removing trees onsite
• Preparing the site to support heavy machinery – this may include compacting soils, paving asphalt access roads, tree removal, and laying gravel

SPU says access to all buildings and businesses will be maintained, but that nearby businesses and residents should expect heavy equipment moving onto the site in April, with early stages of shaft construction starting in May.

In addition, SPU says to expect the following:

• Parking restrictions along the east side of 24th Ave NW so trucks can exit the work site (see map)
• Short interruptions on Shilshole Ave NW for trucks entering the work zone, and 24th Ave NW for trucks exiting the site; please pay attention to flaggers
• Possible one-day lane closures on Shilshole Ave NW and 24th Ave NW for pipe work
• 24th Ave NW Pier will remain closed through 2024

For more information, you can view the full construction notice online.