Ship Canal Water Quality project update 1/28/21

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Photo showing the lower shield of the tunnel boring machine being unloaded in Ballard.

Dear neighbors,
It's here! Our tunnel boring machine arrived from Germany and is making its way to Ballard from the Port of Tacoma. Because the machine is so big, it is arriving in pieces via several oversized deliveries and will be assembled on our Ballard site over the next few months. The photo above shows crews unloading a section of the lower shield last week (see a video here), and the photo below shows what the machine will look like fully constructed.

Photo showing fully constructed tunnel boring machine in Germany.

See additional photos from recent construction activities on Flickr and on SPU's Instagram.


Over the next few weeks, we'll continue installing final concrete walls for the vertical shaft. Additionally, we'll receive and assemble the tunnel boring machine between now and early April. During this time, you can expect:

  • Trucks coming in and out of the site to deliver equipment and over-sized deliveries arriving via Shilshole Ave NW and 24th Ave NW from NW Market St. Some larger deliveries must be made overnight.
  • More heavy equipment to arrive on site, such as cranes.
  • 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. Over the next few weeks, crews will be working 7 am - 2:30 am on weekdays and most Saturdays to prepare for tunneling.

SPU issued a Final Supplemental Environmental Impact Statement (Final SEIS) for the Ship Canal project, including the Ballard Pump Station, in January 2017. After further refining the pump station design, SPU identified two proposed revisions to the Final SEIS:

  • electrical and ventilation elements that would increase the pump station height
  • additional street end improvements on 24th Ave NW

SPU has prepared a State Environmental Policy Act (SEPA) Addendum to document these proposed revisions and to assess how these revisions affect analyses in the Final SEIS. You can review the addendum and find instructions on how to provide public comment here.

East Ballard

Crews will continue soil stabilization and ground improvement work in NW 45th St and 11th Ave NW south of NW 45th St. 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 St, reduced to one lane 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.


Over the next few weeks, crews will dewater the site (pumps inside drilled wells are used to draw down groundwater levels) and excavate the shaft. In mid-February, crews will begin utility work in NW 36th St. 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.
  • Generators running constantly to power the dewatering pumps until permanent power is available on site.
  • As early as late February, crews will install a new water main in NW Leary Way. This work will close up to two travel lanes at a time, but two-way traffic will be maintained and assisted by flaggers. We will send more information about this work in our next update.

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


Secant pile wall construction is underway. 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.
  • Noise from 24/7 on-site generators currently used to power equipment. The generators were placed inside wooden enclosures to lessen noise impacts, and we will continue to look for additional noise-dampening measures while we work towards getting power on site.

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.

Queen Anne

Over the next few weeks, crews will excavate 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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