Ship Canal Water Quality project update 1/5/21

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Ship Canal logoPhoto of Ship Canal staff and their families with a message that says "Happy New Year from our Ship Canal family to yours"

Dear neighbors,
Happy New Year! We're reflecting on everything that we were able to accomplish during a challenging year. In 2020, the Ship Canal Water Quality project got underway in all five neighborhoods. The secant pile walls in Queen Anne and Fremont are complete, and we are breaking ground on this activity in Wallingford. Soil stabilization in East Ballard continues, and we just reached a huge project milestone in Ballard - completing the concrete pour for the 14-ft thick, 87-ft wide shaft floor (check out this video to learn more). 

Remember that intense rainstorm we had just before the holidays? Preliminary data indicates that, over 30 hours, four SPU combined sewer outfalls overflowed 12M+ gallons of polluted stormwater and sewage into the Ship Canal. If the Ship Canal Water Quality Project was operating today, none would have entered our waterways. That's why we're continuing to do this work and making this investment in the Puget Sound's health and the region's future.

We're excited for everything 2021 has in store, like meeting our tunnel boring machine (TBM)! Our TBM has left Germany on a ship and is on its way to Seattle! Watch this video to learn more about the machine as it begins its journey west!


Photo showing a crew member in the vertical shaft working on installing the permanent walls

Installing permanent shaft walls in Ballard

For the next few weeks, we'll be installing final concrete walls for the vertical shaft and electrical equipment. This work is anticipated to last through February. Additionally, we expect to receive and assemble equipment for tunneling between January and April. During this time, you can expect:

  • Trucks coming in and out of the site to deliver equipment.
  • More heavy equipment to arrive on site, such as cranes.
  • Over-sized deliveries arriving via Shilshole Ave NW. Some larger deliveries must be made overnight.
  • Intermittent days of large concrete pours. On these days there will be many trucks delivering concrete to the site, back to back. Work on these pour days may occur well beyond regular working hours due to the amount of concrete that needs to be placed. 

Working hours are expected to be 7 am - 5 pm Monday through Friday. However, night and weekend work will occur to maintain progress.

East Ballard

Crews will continue soil stabilization and ground improvement work in NW 45th St and will begin this activity in 11th Ave NW south of NW 45th St. These activities will help prepare the site for upcoming excavation and underground construction work, like tunneling. During these activities, you should anticipate:

  • NW 45th St closed to traffic; vehicles must detour onto NW 46th St.
  • Burke-Gilman Trail users remain detoured to the north side of NW 45th St; flaggers to help direct traffic during daytime working hours. Please follow all detour guidance on site. Bicyclists must cross train tracks at 90-degree angles. Please use extra caution in wet weather as ramps may be slippery.
  • 11th Ave NW, south of NW 45th, will be reduced to one lane beginning January 2021 and will remain so for most of the year.
  • Two-way traffic on 11th Ave NW will be maintained in the southbound lane (on the west edge of the roadway) via flaggers during working hours and an electronic signal overnight.
  • Noise and vibrations from drill rigs and pumps on site.

Regular work hours will be Monday through Friday, 7 am to 5 pm. Night and weekend work may occur to maintain progress.

See anticipated traffic impacts through 2021 on our website.


The secant pile wall is complete! Crews will dewater the site (pumps inside drilled wells are used to draw down groundwater levels) and will excavate the shaft. Over the next few weeks, you should anticipate:

  • Dump trucks and excavators working on site and an uptick in traffic in Leary Way NW as trucks haul away excavated material.
  • NW 36th St between Leary Way NW and 3rd Ave NW closed (through remainder of the project).
  • Pedestrians detoured to the north side of Leary Way NW.
  • A pump and bypass system running 24/7 to re-route an existing drainage line around the secant pile construction. This system is powered by a generator and will be in place for several more weeks.

Regular work hours will be Monday through Friday, 7 am to 5 pm. Night and weekend work may occur to maintain progress.


Over the next few weeks, crews will dewater the site (pumps inside drilled wells are used to draw down groundwater levels), bring in equipment, and begin secant pile wall construction. Secant pile wall construction will involve several months of intense, loud construction with long work days at the project’s Wallingford site.

You should anticipate:

  • Heavy equipment on site such as the drill rig, an oscillator, and a crane.
    Trucks coming in and out of the site to haul away excavated material and deliver concrete.
  • Noise from the drill rig. This rig is loud and work will start as early as 7 am as allowed by City of Seattle code. We start early in the morning to allow the contractor to complete more of the work during daylight hours to improve safety, to maximize the use of expensive, heavy machinery each day and, to complete work as efficiently and cost-effectively as possible.
  • Vibration from the drill rig. You may be able to feel the vibration in your home or business. This is expected. We are monitoring vibration levels on site to ensure they are within allowable levels.
  • Normal work hours are from 7am to 5pm, Monday through Friday, although work may extend into the early evening, on occasion to complete the concreting of a pile. It’s possible the contractor may also work on Saturdays as needed.

Learn more about the Wallingford secant pile wall in our December 2020 flyer.

Queen Anne

Crews have dewatered the site and are excavating the vertical shaft. During this time, you should anticipate:

  • Trucks coming in and out of the site to haul away excavated material.
  • Noise and vibrations typical of a construction site.
  • The West Ewing Mini Park parking lot closed. This closure is anticipated to last through mid-2023.
  • A localized Ship Canal Trail detour through summer 2022 (see map).

Regular work hours will be Monday through Friday, 7 am to 5 pm. Night and weekend work may occur to maintain progress.

Contact us

Please email with questions or comments or call (206) 701-0233. You can also find information online at


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