Investing in the Health of the Sound and the Future of Our Region
Welcome to the Ship Canal Water Quality Project website! We’re happy you’re here.
We will continue to share updates about construction progress on this website, as they become available.
There's a lot going on at each site. For more information, please read our latest project email posted in the project library.
Wallingford
Closures in Wallingford:
- Stone Way N between N 34th and N 35th St is closed and is anticipated to re-open October/November 2024
- N 34th St at Stone Way N, including the left turn lane from N Northlake Way onto westbound N 34th St is closed and is anticipated to re-open October/November 2024
- The crosswalk on the north side of N 34th St across Stone Way N is also closed and is anticipated to re-open October/November 2024
- Interlake Ave N is closed to through-traffic for utility installation for several more weeks and will remain closed for final pavement restoration through November. During this period, vehicle traffic on Interlake Ave N south of N 36th St will be local access only down to N 35th St.
Work is weather dependent. We will continue to keep the website updated with the most current schedule information and provide updates in the project email we send out every two weeks. Sign up to receive our email to the right. See our updated detour map for more information about detours.
Ballard
Later this fall, work will begin on the Ballard conveyance project and the Ballard pump station. The Ballard conveyance project includes the installation of a 2000-ft long, 60-in diameter pipeline in Ballard along 24th Ave NW, NW 56th St, and 28th Ave NW. The pump station will be built at the 107-ft deep, 80-ft diameter vertical shaft that was used for tunneling.
We will continue to keep the website updated with the most current schedule information.
East Ballard
NW 45th St and 11th Ave NW are expected to be fully reopened the week of October 7 and the Burke Gilman Trail (BGT) will be moved back to it’s original location at the same time. Some landscaping, fencing, and commissioning work remains.
Fremont
Lane restrictions in Leary Way NW will continue through October for final paving. The contractor has started final restoration along Leary Way NW.
Queen Anne
Crews have completed site restoration. The Ship Canal Trail is currently open in its original configuration. There may be localized trail detours in coming months as needed for crews to work.
Support our local businesses
We understand the challenges of living and working in a construction area. We continue to keep an eye on neighborhood impacts across our project areas 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.
Click on the project areas to learn more
About the project
Seattle Public Utilities and King County Wastewater Treatment Division are building an underground storage tunnel to significantly reduce the amount of polluted stormwater (from rain) and sewage that flows into the Lake Washington Ship Canal, Salmon Bay, and Lake Union from our sewer system.
In some parts of Seattle, sewage and stormwater (rain) share a set of pipes; this is called a combined sewer. During heavy rains (What? Rain? Here?) the water often exceeds the pipes’ capacity (known as an overflow to us sewer nerds), sending untreated sewage (yep, that means poop) and stormwater into the Ship Canal. These overflows can harm fish, wildlife, and the environment, and can contain pollution.
During a heavy storm, the new tunnel will capture and temporarily store more than 30 million gallons of untreated stormwater and sewage until the treatment plant is ready for it. The tunnel will improve water quality regionally by keeping more than 75 million gallons of polluted stormwater (from rain) and sewage on average each year from flowing into the Lake Washington Ship Canal, Salmon Bay, and Lake Union. Based on data from the last five years, the Ship Canal Water Quality Project would have removed about 70% of SPU’s total combined sewer overflow volume.
This storage tunnel (completed) and the conveyance pipes in Wallingford (under construction) are two of several components that comprise the Ship Canal Water Quality Project. The total cost for the overall Ship Canal Water Quality Project is around $710 million dollars.
Check out this video, made in 2020, for an overview of the project.
Tunnel
MudHoney, the 18-ft diameter tunnel boring machine, completed its journey from Ballard to Wallingford in June 2023!
Since the 1800s, 150 tunnels spanning over 70 miles have been constructed in Seattle for sewers, utility corridors, and transportation needs. The Ship Canal Water Quality Project includes a 2.7-mile, 18-ft and 10-in internal-diameter tunnel that extends from Ballard to Wallingford. Tunneling operations started in Ballard. The Ballard vertical access shaft construction started in 2020 with tunneling completion in 2023.
The purpose of the tunnel is to collect and hold stormwater and sewage flows which would normally overflow into the Ship Canal. Along the tunnel path, there are five vertical shafts (in Ballard, East Ballard, Fremont, Queen Anne, and Wallingford). They will collect stormwater and sewage flows from each basin and send them approximately 40 – 80 ft below ground into the new storage tunnel. In order to bring flows from Queen Anne into the storage tunnel, SPU built an 8-ft diameter conveyance tunnel underneath the Ship Canal connecting the vertical shafts in Queen Anne and Fremont. For the final piece of the SCWQP, SPU will install new pipes to connect the existing sewer systems to the new shafts.
In addition to MudHoney, our roughly 18-ft diameter tunnel boring machine that constructed the storage tunnel, did you know that our project is also building a couple of other, smaller tunnels? We are using smaller tunneling machines for two conveyance tunnels, one went under the Ship Canal between Fremont and Queen Anne, and the other one will be used in Ballard. Both of these smaller conveyance tunnels will be used to carry flows to the storage tunnel. The Ballard tunnel will begin construction in 2024.
See the table below to learn more about the differences between these TBMs and check out our storage tunnel TBM factsheet for more information!
Tunnel Boring Machine Comparison
MudHoney, 18-ft Storage Tunnel TBM | 8-ft Conveyance Tunnel TBM *Note that we do not yet have information about the Ballard TBM | |
---|---|---|
Type of Machine | Earth Pressure Balance Pressurized face TBM | Slurry pressurized face TBM |
Manufacturer | Germany | Germany |
Age | Newly manufactured in 2020 | Manufactured in 2014 and refurbished from King County's Fremont Siphon Project |
Length | 14,256-ft | 646-ft |
Length of TBM shield This is the part of the machine that isolates the TBM equipment from the surrounding ground |
31-ft 2-in | 22-ft 7-in |
Number of cutterhead tools | 18 double-disc cutters 48 scrapers 16 bucket cutters |
12 double-disc cutters 16 scrapers 14 chisels |
How do we operate the TBM? | Operated by crews in a control room inside the front of the TBM | Operated remotely by crews above ground |
Number of staff needed to operate | 10-15 people | 6-10 people |
Diameter of TBM The TBM has to drill a hole larger than the final tunnel size to have space to build the concrete tunnel liner |
21-ft 8-in | 9-ft 10-in |
Finished tunnel diameter | 18-ft 10-in | 8-ft 0-in |
Tunnel construction | 6 concrete segments combined to form a ring | Concrete reinforced pipe |
In early 2021, we asked the community to help us name the 18-ft storage tunnel boring machine (TBM). We received over 1,200 TBM name submissions and over 30,000 votes! MudHoney was the ultimate winner. The name was painted on the front of the TBM by Devin Finley in April 2021.
Devin Finley is a muralist who specializes in large scale inspired murals. He started as a graffiti artist at age 15 because he loved street accessible art. He became a professional muralist in 2013 and works on both private and public projects. He likes working with clients and audiences to develop engaged and meaningful concepts. His project “MUDHONEY” was painted onto the project’s tunnel boring machine on April 5, 2021. The TBM was named "MudHoney" and Devin used lettering and water droplets to connect the enormous machine, one of Seattle’s famous grunge bands, and rain-- which is part of the reason for the project.
While no significant ground movement is anticipated, as a precaution, crews will be monitoring over 200 structures along the tunnel path before, during, and after tunnel construction. To learn more about ground monitoring, read our fact sheet.
Ballard
Learn more about the Ballard site
Ballard is home to the western end of the tunnel and above-ground facilities supporting the tunnel. Tunnel boring started at this site before it made its way to Wallingford.
We started work at our site near 24th Ave NW and Shilshole Ave NW in 2018 to prepare for tunneling. This work included soil remediation, utility relocation, 24th Ave Pier replacement, and replacing a sewer outfall pipe.
Project elements in Ballard include:
- A new pipe in Ballard that will convey polluted stormwater and sewage from the Ballard neighborhood into the storage tunnel. This pipe will run along 24th Ave NW, NW 56th St, and 28th Ave NW.
- A new 80-ft tall pump station at the 107-ft deep, 80-ft diameter vertical shaft that was used for tunneling. The pump station will take flows from the tunnel to the West Point Treatment Plant.
- A new 24th Ave NW Pier containing art inlays by artist Christian French (This pier is completed, publicly accessible, and managed by Seattle Department of Transportation.)
After construction is completed at the Ballard site, you can expect to see:
- Ballard Pump Station (not publicly accessible):
- 80-ft illuminated tower with above- and below-ground mechanical equipment and odor control
- Maintenance yard with vehicle access
- An urban tree farm
- Landscaping
- Fencing
- 24th Ave NW Restoration
- Green stormwater infrastructure
- Pedestrian improvements, including seating and bike racks
- Parking improvements
- Street-end improvements
- Public art by artist Jeffrey Veregge
To learn more about the Ballard project site, read our fact sheet.
Our designers have been inspired both by our underground infrastructure and the Ballard community. The cylindrical shape mirrors the pump station and below-ground equipment space. The frame around the building echoes the industrial feel and scaffolding of Ballard's shipyards. Near the tower will be smaller buildings for equipment as well as parking for our amazing maintenance crews.
Artwork developed byJeffrey Veregge, from the Port Gamble S'Kallam Tribe, celebrates the Coast Salish heritage and historical use of the area.
To learn more about the Ballard project site, read our fact sheet or check out this introductory video. For more details about future site improvements, take a look at our Ballard Pump Station Flickr album.
Now that the new storage tunnel has been built, crews will install a 2,000-ft long, 60-in diameter pipeline in Ballard along 24th Ave NW, NW 56th St, and 28th Ave NW to convey polluted stormwater and sewage from the Ballard neighborhood into the storage tunnel.
During work in this area, you can expect single-lane and full-street closures, intersection closures, and parking restrictions on impacted blocks. We will provide more updates and information about these impacts as we get closer to the start of this work.
Ballard schedule
- Crews will generally work Monday through Friday from 7 am to 5 pm
- Possible weekend and nightwork to maintain progress
- Parking restrictions along the east side of 24th Ave NW, NW 56th St, and 28th Ave NW so construction trucks can exit the work site
- Trucks and large equipment moving in and out of the work zone
- Short interruptions on Shilshole Ave NW for trucks entering the work zone, and on 24th Ave NW for trucks exiting the site; please pay attention to flaggers
- Noise typical of a large construction site
- Access to all buildings and businesses will be maintained
East Ballard
Learn about the East Ballard site
Project elements in East Ballard include:
- A new 55-ft deep, 10-ft diameter vertical shaft, also called a drop shaft, near the intersection of 11th Ave NW and NW 45th St to carry sewage to the new storage tunnel
- A new below-grade structure to house mechanical, electrical, and odor control equipment
- A new diversion structure, gate vault, and conveyance pipes to connect the existing sewer and stormwater overflow pipe to the storage tunnel
To learn more about the East Ballard project site, read our fact sheet.
East Ballard schedule
- Crews will generally work Monday through Friday from 7 am to 5 pm
- Possible weekend and nightwork to maintain progress
- Construction-related noise, traffic, dust, and vibrations
- The Burke-Gilman Trail will be detoured to the north side of NW 45th St
- Periodic traffic impacts to 11th Ave NW and NW 45th St, including one-lane and full-road closures, now through 2024
- Flaggers will help direct traffic during work hours
- Removal of some trees in the project area
- Increased truck traffic
- Parking restrictions
Fremont
Learn about the Fremont site
The 8-ft diameter conveyance tunnel boring machine reached its destination in Queen Anne in early February 2023! Crews are installing piping and an air duct inside the 8-ft diameter tunnel casing and working on the diversion structure.
Project elements in Fremont include:
- A new 85-ft deep, 32-ft diameter vertical shaft, also called a drop shaft, to carry sewage and stormwater into the new storage tunnel
- A new diversion structure and conveyance pipe to connect the existing sewer and stormwater overflow pipes to the storage tunnel
- A new 8-ft diameter conveyance tunnel under the Ship Canal to carry flows from Queen Anne to the storage tunnel
- A new underground structure to house mechanical, electrical, and odor control equipment
Artists Preston Singletary and David Franklin collaborated on artwork for the Fremont and Queen Anne sites. This artwork is planned to be installed in 2024.
To learn more about the Fremont project site, read our fact sheet.
Fremont schedule
- Crews will generally work Monday through Friday from 7 am to 5 pm
- Possible weekend and nightwork to maintain progress
- Full closure of NW 36th St between Leary Way NW and 3rd Ave NW
- Closure of 2nd Ave NW between Leary Way NW and NW Canal St
- Temporary roadway detours on streets adjacent to the project area. Leary Way NW will remain open to traffic, but several lanes will be temporarily closed for construction.
- Pedestrian sidewalk detour on north side of Leary Way NW
- Increased truck traffic
- Parking restrictions near work zone
- Burke-Gilman Trail to remain open except temporary impact during conduit installation (likely one week)
Queen Anne
Learn about the Queen Anne site
Project elements in Queen Anne include:
- A new 8-ft diameter tunnel under the Ship Canal to carry stormwater and sewage from Queen Anne to the new storage tunnel
- A new 74-ft deep, 20-ft diameter vertical shaft, also called a drop shaft, to direct flows into the new 8-ft diameter tunnel
- New structures and conveyance pipes to connect the existing sewer and stormwater overflow pipe to the new vertical shaft
Artists Preston Singletary and David Franklin have collaborated on artwork for the Fremont and Queen Anne sites. This artwork is planned to be installed in 2024.
To learn more about the Queen Anne project site, read our fact sheet.
Queen Anne schedule
- Construction-related noise, traffic, dust, and vibrations
- Vehicle, pedestrian, and bicycle wayfinding and detour signage
- Increased truck traffic along W Nickerson St and 3rd Ave W
- Parking restrictions and roadway detours
- Ship Canal Trail detour through May 2024
- Closure of West Ewing Mini Park and associated parking lot through May 2024
Wallingford
Learn about the Wallingford site
Wallingford marks the eastern end of the Ship Canal Water Quality Project and the location where tunneling ended underneath N 35th St and Interlake Ave N in June 2023. Construction will continue to take place on Stone Way N, N 34th St, N 35th St, and Interlake Ave N.
Project elements in Wallingford include:
- A new 56-ft deep, 32-ft diameter vertical shaft, also called a drop shaft, near Stone Way N and N 35th St to convey stormwater and sewage into the tunnel
- New conveyance pipe installation along Stone Way N and N 35th St to connect the existing sewer and stormwater overflow pipe to the storage tunnel
- A new small, above-ground electrical building near 3500 Interlake Ave N
- New underground structures to house mechanical, electrical, and odor control equipment
- Site and roadway restoration
- Public art by Ryan! Feddersen
Once construction at the Wallingford site is complete, SPU will retain ownership of the southern portion of the site. The site will be mostly fenced to secure utility equipment. The fenced area will house an aboveground electrical building, and several large, underground structures attached to the storage tunnel.
The design for the Wallingford site is complete. During design, our landscape architects reviewed the planting schemes for the North Transfer Station and the Carr Place Play Area. Their goal was to create a site that was unique to the neighborhood but still complemented the aesthetic of nearby open spaces.
Artist Ryan! Feddersen will design and install the artwork at this project site.
To learn more about the Wallingford project site, read our fact sheet.
As part of the Ship Canal Water Quality project, SPU needs to build new pipes (and very deep trenches for them) to connect Wallingford’s existing combined sewer outfall pipe to the storage tunnel. This new pipe will move polluted stormwater and sewage into the storage tunnel to prevent overflows into Lake Union. Crews are installing a 213-ft-long, 36-in diameter pipe along Stone Way N; a 412-ft-long, 42-in diameter pipe along N 35th St; and a diversion structure near the intersection of Stone Way N and N 34th St. We expect the project to be completed by the end of 2024.
The work taking place requires street closures and parking restrictions. As of February 2023, Stone Way N, between N 35th St and N 34th St, is closed. The intersection at Stone Way N and N 34th St, including the left turn lane onto N Northlake Way, will be closed intermittently. As of September 2023, N 35th St is closed between Stone Way N and Interlake Ave N. N 35th St and N 34th St will not be closed at the same time. During construction, you can expect traffic detours and detours of Metro bus routes 31, 32 and 62.
Is SPU closing Stone Way N completely?
Yes, between N 35th St and N 34th St. To put a pipe under Stone Way N, our contractor must install an underground structure that takes up most of the street and dig extremely deep trenches – 25 ft deep! The road remains closed to vehicular traffice in order to maintain a safe working environment for our crews and the community. Sidewalks on the east and west sides of Stone Way N remain open when possible and crosswalks may be affected. Bicycles are detoured via Wallingford Ave N, N 36th St, and Troll Ave N.
Stone Way N closure area map - updated Dec 2022 (click or tap image to enlarge)
How should I get to (insert favorite business here)?
Businesses remain open and accessible during construction. SPU has been working closely with businesses in the area to ensure that we can meet their access needs.
How will this affect my commute?
New vehicle, bicycle, and pedestrian detour maps will help you navigate the area. A note to people riding bicycles, please remember to dismount and walk your bike for safety on sidewalks. These detours are expected to remain in place until late 2024.
Wallingford schedule
- Construction-related noise, traffic, dust, and vibrations
- Sidewalk closure on the east side of Interlake Ave N
- Long-term road closures on Stone Way N and N 35th St
- Parking restrictions and roadway detours
- Temporary closures and impacts on Interlake Ave N and N 34th St with flaggers present to direct traffic
- Removal of some trees in the project area