Ship Canal Water Quality Project update 11/2/2023

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Ready for some concrete answers to your heavily cemented questions on Ship Canal?

Concrete pour processes

At the Wallingford shaft site, crew members work from the scissor lift to set interior walls on the left; a worker secures rebar to the wall in preparation for concrete pour on top right; and workers place the first round of concrete for a wall on bottom right.

Concrete is one solid substance. It’s a common building material that's used in all kinds of construction, from sidewalks and driveways to buildings, bridges, and even large shafts. It’s made of cement, sand, gravel, and water. Wait, cement and concrete are different? Yes! Cement is one of the main ingredients in concrete, and it’s super important for strength and durability. Cement acts as a binding agent – like the glue that holds everything together. When you mix cement with water, it forms a paste that sticks to the tiny particles of sand and gravel (the aggregate) in the concrete mix. This paste hardens and binds the aggregate particles together, creating a solid and strong material.

We’ve been using concrete pours at our shaft sites to create strong, durable, and lasting cement shaft walls. First, our workers set up special molds, or “forms”, made from wood or a plastic material in an outline. Then the workers place the rebar inside the forms. Once the concrete is mixed, we pour it into the forms. We need to do many concrete pours because our sites are so big and one wall has to cure before an adjacent wall can be poured! After the concrete is poured, it takes up to a few weeks to cure, harden, and reach the design strength. Finally, when the concrete has solidified, workers will remove the forms, leaving behind a solid, vertical wall.

Visit our project website to learn more about the project and check out our Flickr albums for recent construction photos. Thank you!



Crews continue to dismantle, clean, and remove the equipment that was needed to build the tunnel.

You should anticipate:

  • Nighttime truck movements may be necessary to remove large equipment over the next few months
  • Noise and vibrations typical of a construction site

Crews continue working two shifts, 20 hours a day, six days a week. Some work may occur on Sundays.


East Ballard

Crews continue to build the adit from within the tunnel and are completing the isolation maintenance hole structure on 11th Ave NW. Starting next week, crews will begin replacing a segment of water main in NW 45th St between 11th Ave NW and 9th Ave NW.

Local closures and detours:

  • There continues to be a one-lane traffic configuration on 11th Ave NW at NW 45th St. Traffic signals and flaggers will direct traffic at the intersection during single lane closures.
  • NW 45th St remains closed to traffic between 11th Ave NW and 9th Ave NW. Vehicles must detour onto NW 46th St.
  • Burke-Gilman Trail (BGT) remains detoured to the north side of NW 45th St through the project area. For safety, bicyclists should either dismount or cross train tracks at a 90-degree angle. Please take extra caution in wet weather as ramps may be slippery.

You should anticipate:

  • Heavy equipment in the area
  • Noise and vibrations typical of a construction site

Regular work hours will be Monday through Friday, from 7 am to 6 pm. Night and weekend work may occur.



Crews continue building the permanent structure inside the shaft, constructing the adit, and installing conveyance pipes that connect to the storage tunnel. They also continue building the large underground mechanical and electrical vault.

Crews have begun work replacing a segment of water main in Leary Way NW.

Local closures and detours:

  • Leary Way NW is reduced to one lane each direction until early December for water main work
  • The water main work will also require short-term overnight work to connect the new water main to the existing system. Customers will be notified of any water service interruptions.
  • On 2nd Ave NW, between Leary Way NW and NW Canal St, the street remains closed to vehicle and pedestrian traffic through 2023
  • NW Canal St is open to two-way traffic during this closure
  • NW 36th St, between Leary Way NW and 3rd Ave NW, remains closed through 2023
  • Pedestrian detours are in place on Leary Way NW; please follow all detour guidance

You should anticipate:

  • Truck traffic on Leary Way NW as trucks bring materials and equipment to and from the site
  • Concrete trucks entering and leaving the site
  • Fans running during work hours to provide fresh air to crews working in the shaft
  • Heavy equipment in the area
  • Noise and vibrations typical of a construction site

Regular work hours will be Monday through Friday, from 7 am to 6 pm; and some Saturdays from 9 am to 6 pm.


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Our contractor installed maintenance hole structures and replaced a segment of sewer pipe, and is continuing installation of the conveyance pipe on N 35th St between Interlake Ave N and Stone Way N.

We understand that traffic is a challenge in this area. We continue to keep an eye on neighborhood impacts and add new signage for detours and safe access to businesses. Businesses are open and ready to serve the community. Please support local businesses and follow all detour signage and safety directions when traveling through the work area.

See our detour maps for cyclists and pedestrians.

N 35th St closure vehicle detour:

  • Check out the vehicle detour map
  • Traffic is detoured via N 40th St and Wallingford Ave N, and via Woodland Park Ave N and N 34th St
  • The all-way stops remain in place at Woodland Park Ave N at both N 35th St and N 34th St, and also at Wallingford Ave N and N 35th St
  • Stone Way N between N 34th St and N 35th St remains closed to vehicles and bicycles
  • Please adhere to the Road Closed, Local Access Only, and Traffic Revision Ahead signage and follow marked detour routes

N 35th St closure bicycle detour

  • Check out the bicycle and pedestrian detour map
  • Bicyclists are detoured to the west on N 35th St and to the south on Woodland Park Ave N
  • Access to the Burke Gilman Trail is on N 34th St at Stone Way N and at Troll Ave N
  • Please dismount and walk if you use the sidewalk

You should anticipate:

  • N 35th St between Stone Way N and Interlake Ave N and the intersection of N 35th St and Stone Way N are closed
  • Trucks coming in and out of the site
  • Heavy equipment in the area
  • Vibrations typical of a construction site
  • Road and periodic sidewalk closures
  • Temporary bus stop on Woodland Park Ave N is being relocated and Metro bus routes 31, 32, and 62 have been detoured. Please view service advisories on King County Metro’s website.

Regular work hours at the Wallingford shaft site will be Monday through Friday, from 7 am to 6 pm. Crews also work a second shift in the tunnel and there will be occasional surface work at the shaft site.

Regular work hours on N 35th St and Stone Way N will be Monday through Friday, 7 am to 6 pm. Night and weekend work may occur periodically.


Queen Anne

Crews continue to build walls for the permanent structure as well as pipes and utilities inside the shaft. Crews are also installing storm drainage utilities at the site.

Local closures and detours:

  • Localized Ship Canal Trail detour at least through 2023 (see map). Please continue to remain alert when moving through this area.
  • West Ewing Mini Park parking closure through 2023

You should anticipate:

  • Trucks coming in and out of the site
  • Heavy equipment in the area
  • Noise and vibrations typical of a construction site

Regular work hours will be Monday through Friday, from 7 am to 6 pm. Night and weekend work may occur.

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Contact Us

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

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