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.

Currently, the Seattle Public Utilities is planning to continue with construction in your area. We are working closely with our Public Health – Seattle & King County partners, our construction management teams, and private contractors to ensure that everyone supporting this project is cautious and safe. If there are changes to the construction schedule or planned work, we will notify you once public information is available.

The City of Seattle and King County are taking steps to protect the health of our community by making recommendations that are meant to slow the spread of novel coronavirus and reduce the number of people infected. Please learn more about COVID-19 at www.kingcounty.gov/covid. Thank you.

We will continue to share updates about construction progress on this website, as they become available.

What’s happening now?

Getting ready for secant piles in Fremont and Queen Anne

In September, we’re planning to start shaft construction in Fremont and Queen Anne. Shaft construction will start with installing “secant pile” walls [links to project glossary]. A secant pile wall is a type of construction used to support underground excavations. It is made up of overlapping vertical concrete piles, which together hold back surrounding soil to allow for excavation and underground construction. To create a pile, a hole is bored into the ground using a drilling machine and is filled with concrete. During this phase of construction, you should anticipate:

More heavy equipment on site like the drilling machine, crane and rebar cages.
Noise and vibration from the drilling machine. If you live or work within a few blocks of a site, you may be able to feel the vibration in your building. This is expected. We are monitoring vibration levels on site to ensure they are within allowable levels.
Trucks in and out of the site to haul away excavated material and deliver concrete.

24th Ave NW pier to stay open for now

Ballard’s 24th Ave NW pier will remain open until further notice because our tunneling contractor does not currently need it for construction activities.

More art at our construction sites

Our first round of temporary art is now installed in four neighborhoods. Check out the new art tab on our website to learn more.

Murals placed along the Wallingford screen wall in late July 2020. The murals depict 4 killer whales and are drawn in form design. In the middle of the images is a white sign that states Protect the sacred, Missing Murdered Indigenous Women. — Mural was placed on the Wallingford screen wall in late July 2020 | Click to enlarge

View archived project announcements

Project Area (Click or tap image to enlarge)

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.

Learn more about the project

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.

In 2018, 84% of the city’s overflows came from the combined sewers in Crown Hill, Ballard, Fremont, Wallingford, Queen Anne, Downtown, and Capitol Hill. During a heavy storm, the new tunnel will capture and temporarily store more than 29 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.

During dry weather conditions, sewage flows directly to a treatment plant. (Click or tap image to enlarge)

During heavy rain, sewage and stormwater can overflow into a nearby body of water. (Click or tap image to enlarge)

Tunnel

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 will extend from Ballard to Wallingford. Tunneling operations will start in Ballard. The Ballard vertical access shaft will begin construction in 2020 and tunneling is planned to begin in 2021.

Learn more about the tunnel

Along the tunnel path, five large vertical shafts will be built (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 addition to the storage tunnel, SPU will build an 8-ft diameter microtunnel underneath the Ship Canal connecting the vertical shafts in Queen Anne and Fremont. SPU will install new pipes to connect the existing sewer system to the new drop shafts.

Diagram explains how the new Ship Canal Storage Tunnel works — How the new Ship Canal Storage Tunnel works. (Click or tap image to enlarge)

Learn about ground monitoring

Ballard

Construction in Ballard is underway

Work in Ballard began in late February 2020.

Throughout the summer, crews will be focused on slurry wall and vertical shaft construction.

aerial map of area between 24th avenue North West and Shilshole Avenue Northwest. Tunnel barging operations are southwest of the 24th avenue pier in Salmon Bay. Dotted lines along 24th Avenue Northwest and Northwest 56th Street indicate locations for conveyance pipe alignment and microtunnel placement. A dark blue line that runs through Shilshole Avenue Northwest denotes the storage tunnel. — Construction area map (Click or tap image to enlarge)

What to expect during near-term construction

projected construction schedule. Includes Construction methods and milestones, the year each construction milestone and method will take place. A blue star under the year 2025 denotes Storage tunnel operationa — Ballard construction schedule (Click or tap image to enlarge)

Crews will generally work from 7 a.m. to 5 p.m., Monday through Friday
- Possible weekend and nighttime work to maintain progress
Possible 1-day lane closure on Shilshole Ave NW and 24th Ave NW for pipe work
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
Parking restrictions along the east side of 24th Ave NW so construction trucks can exit the work site
24th Ave NW Pier may have intermittent closures throughout construction
Noise typical of a large construction site
Access to all buildings and businesses will be maintained

Learn more about the Ballard site

Ballard will be home to the western end of the tunnel and above-ground facilities supporting the tunnel. Tunnel boring will start at this site and move toward Fremont and Wallingford.

We started work at our site near 24th Ave NW and Shilshole Ave NW in 2018 to prepare for upcoming tunneling. This work includes soil remediation, utility relocation, 24th Ave Pier replacement, and replacing a sewer outfall pipe.

Project elements in Ballard include:

A new 100-ft deep, 90-ft diameter shaft to hold pump station equipment and carry sewage and stormwater into the new storage tunnel
New pipes along NW 56th St, 28th Ave NW and 24th Ave NW to connect the shaft to Ballard’s existing combined sewer system overflow pipe
A large pump station that will take the flows from the tunnel and send them to West Point for treatment
A new 24th Ave Pier contains art inlays by artist Christian French

After construction is completed at the Ballard site, you can expect to see:

Ballard Pump Station (not publicly accessible):
- 65-ft illuminated tower with above- and below-ground mechanical equipment and odor control
- Maintenance yard with vehicle access
- Landscaping
- Fencing
24th Ave NW Restoration (publicly accessible)
- Green stormwater infrastructure
- Pedestrian improvements
- Parking improvements
- Street-end improvements

About the Ballard Pump Station concept: 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.

Artist Jeffrey Veregge is working to create public art for the pump station.

To learn more about the Ballard project site, read our fact sheet.

An animated depiction of the future Ballard pump station during a sunset. The cylinder-shaped pump station contains an argyle-styled fence that encases the pump station itself. — Rendering of future Ballard Pump Station. (Click or tap image to enlarge)

East Ballard

Construction in East Ballard is underway

Construction in East Ballard at NW 45th St and 11th Ave NW started in June 2020.

For the remainder of 2020, crews will:

Stabilize soils for underground construction work
Begin diversion structure construction

aerial map shows area on Northwest 45th Street and is between 11th Avenue North West and 9th Avenue Northwest. Grey dotted lines along 45th Avenue Northwest and indicate the future missing link route, orange dotted lines along 45th Avenue Northwest indicate the proposed trail detour and green dotted lines indicate the Burke-Gilman Trail. The solid blue line on 11th Avenue Northwest indicates underground pipes.. — Construction area map (Click or tap image to enlarge)

What to expect during construction

Work hours will be from 7 a.m. to 5 p.m., Monday through Friday
- Possible weekend and nightwork to maintain progress
The Burke-Gilman Trail will be detoured to the north side of NW 45th St beginning as early as April 2020
Traffic impacts to 11th Ave NW and NW 45th St, including one-lane and full-road closures, will occur intermittently now through 2022. Please refer to and scroll through the East Ballard phasing diagram below to see what traffic impacts you should anticipate during a specific time period. Schedule is subject to change.

An aerial map of the Ship Canal Water Quality Project East Ballard site from now until Early August 2020. The base map shows the approximate work zone in a red box that runs from the intersection of 11th avenue Northwest and northwest 45th street. This box extends along one lane of Northwest 45th Street. A dotted line runs along Northwest 45th Street and depicts the Burke-Gilman trail detour. Parallel to the dotted blue line are black arrows that run east and indicate the traffic flow on impacted roadways. Black arrows also are located on 11th Avenue Northwest and go both directions to indicate traffic flow on impacted roadways. — Click to enlarge

Now - Early August 2020*

NW 45 th St closed to westbound traffic; westbound vehicles must detour onto NW 46 th St.
NW 45 th St allows eastbound traffic to travel in westbound lane.
11 th Ave NW allows two way traffic via one lane controlled by flaggers during work hours and an electronic signal overnight.
Trail users detoured to the north side of NW 45 th St; flaggers to help direct traffic during work hours.

*There will be no road closures Thanksgiving through New Years. Schedule is approximate and subject to change.

An aerial map of the Ship Canal Water Quality Project East Ballard site from August 2020 to Early December 2020. The base map shows the approximate work zone in a red box that runs from the intersection of 11th avenue Northwest and northwest 45th street. This box extends along both lanes of Northwest 45th Street. A dotted line runs along Northwest 45th Street and depicts the Burke-Gilman trail detour. Black arrows at the Northeast intersection of 11th Avenue northwest and northwest 45th Street two way-traffic will be allowed via one lane that will be controlled by flaggers. Black arrows also are located on 11th Avenue Northwest and go both directions to indicate traffic flow on impacted roadways. — Click to enlarge

Aug. - Early Dec. 2020*

Soil stabilization work

red box indicating approximate work zone Approximate work zone

blue dashed line indcating burke-gilman trail detour Burke-Gilman Trail detour

NW 45 th St closed to traffic; vehicles must detour onto NW 46 th St.
11 th Ave NW allows two way traffic via one lane controlled by flaggers during work hours and an electronic signal overnight.
Trail users detoured to the north side of NW 45 th St; flaggers to help direct traffic during work hours.

*There will be no road closures Thanksgiving through New Years. Schedule is approximate and subject to change.

An aerial map of the Ship Canal Water Quality Project East Ballard site from mid-December 2020 to early March 2021 The base map shows the approximate work zone in a red box that runs from the intersection of 11th avenue Northwest and northwest 45th street. This box extends along one lane of Northwest 45th Street. A dotted line runs along Northwest 45th Street and depicts the Burke-Gilman trail detour. Parallel to the dotted blue line are black arrows that run east and indicate the traffic flow on impacted roadways. Black arrows also are located on 11th Avenue Northwest and go both directions to indicate traffic flow on impacted roadways. Black hours on the right side of Northwest 45th street show that traffic will be closed westbound but will allow eastbound traffic to travel in the westbound lane. — Click to enlarge

Mid - Dec. 2020 Early March 2021*

Shoring installation, diversion structure excavation

red box indicating approximate work zone Approximate work zone

blue dashed line indcating burke-gilman trail detour Burke-Gilman Trail detour

NW 45 th St closed to westbound traffic; westbound vehicles must detour onto NW 46 th St.
NW 45 th St allows eastbound traffic to travel in westbound lane.
11 th Ave NW allows two way traffic via one lane controlled by flaggers during work hours and an electronic signal overnight.
Trail users detoured to the north side of NW 45 th St; flaggers to help direct traffic during work hours.

*There will be no road closures Thanksgiving through New Years. Schedule is approximate and subject to change.

An aerial map of the Ship Canal Water Quality Project East Ballard site from March 2021 to September 2021 The base map shows the approximate work zone in a red box that runs from the intersection of 11th avenue Northwest and northwest 45th This box extends along both lanes of Northwest 45th Street. A dotted line runs along Northwest 45th Street and depicts the Burke-Gilman trail detour. Black arrows on 11th Avenue Northwest indicate that traffic will be allowed two ways via one controlled lane. Black hours at the east side of Northwest 45th street indicate that traffic will be closed on that street. — Click to enlarge

March - Sept. 2021*

Diversion structure, vault and drop shaft installation

red box indicating approximate work zone Approximate work zone

blue dashed line indcating burke-gilman trail detour Burke-Gilman Trail detour

NW 45 th St closed to traffic; vehicles must detour onto NW 46 th St.
11 th Ave NW allows two way traffic via one lane controlled by flaggers during work hours and an electronic signal overnight. Note, 11 th Ave NW expected to fully open to traffic in July 2021.
Trail users detoured to the north side of NW 45 th St; flaggers to help direct traffic during work hours.

*Schedule is approximate and subject to change.

An aerial map of the Ship Canal Water Quality Project East Ballard site from September 2021 to January 2022. The base map shows the approximate work zone in a red box that runs from the intersection of 11th avenue Northwest and northwest 45th street. This box extends along one lane of Northwest 45th Street. A dotted line runs along Northwest 45th Street and depicts the Burke-Gilman trail detour. Parallel to the dotted blue line are black arrows that run east and indicate that Northwest 45th Street will be closed to westbound traffic. — Click to enlarge

Sept. 2021 - Jan. 2022*

Complete vault and drop shaft installation, install associated utilities

red box indicating approximate work zone Approximate work zone

blue dashed line indcating burke-gilman trail detour Burke-Gilman Trail detour

NW 45 th St closed to westbound traffic; westbound vehicles must detour onto NW 46 th St.
NW 45 th St allows eastbound traffic to travel in westbound lane.
11 th Ave NW fully open to two way traffic.
Trail users detoured to the north side of NW 45 th St; flaggers to help direct traffic during work hours.

*There will be no road closures Thanksgiving through New Years. Schedule is approximate and subject to change.

An aerial map of the Ship Canal Water Quality Project East Ballard site from late January 2022 to July 2022. The base map shows the approximate work zone in a red box that runs from the intersection of 11th avenue Northwest and northwest 45th street. This box extends partway along Northwest 45th Street. A dotted line runs along Northwest 45th Street and depicts the Burke-Gilman trail detour. — Click to enlarge

Late Jan. - July 2022*

Complete vault and drop shaft installation, install associated utilities

red box indicating approximate work zone Approximate work zone

blue dashed line indcating burke-gilman trail detour Burke-Gilman Trail detour

NW 45 th St fully open to two way traffic.
11 th Ave NW fully open to two way traffic; east sidewalk closed.
Trail users detoured to the north side of NW 45 th St; flaggers to help direct traffic during work hours.

*Schedule is approximate and subject to change.

An aerial map of the Ship Canal Water Quality Project East Ballard site from late July 2022 to November 2022 The base map shows the approximate work zone in a red box that runs from the intersection of 11th avenue Northwest and northwest 45th This box extends along both lanes of Northwest 45th Street. A dotted line runs along Northwest 45th Street and depicts the Burke-Gilman trail detour. Black arrows on 11th Avenue Northwest indicate that traffic will be allowed two ways via one controlled lane. Black arrows at the east side of Northwest 45th street indicate that traffic will be closed on that street. — Click to enlarge

Late July - Nov. 2022*

Adit excavation, vent shaft installation, final restoration

red box indicating approximate work zone Approximate work zone

blue dashed line indcating burke-gilman trail detour Burke-Gilman Trail detour

NW 45 th St closed to traffic; vehicles must detour onto NW 46 th St.
11 th Ave NW allows two way traffic via one lane controlled by flaggers during work hours and an electronic signal overnight.
Trail users detoured to the north side of NW 45 th St; flaggers to help direct traffic during work hours.

*There will be no road closures Thanksgiving through New Years. Schedule is approximate and subject to change.

Previous Next

Learn about the East Ballard site

Project elements in East Ballard include:

A new 60-ft deep, 10-ft diameter vertical shaft to carry sewage to the new storage tunnel
New pipe installation along NW 45th St to connect the current combined sewer system overflow pipe to the new vertical shaft and storage tunnel
A new below-grade structure to house mechanical and electrical equipment and odor control

To learn more about the East Ballard project site, read our fact sheet.

Fremont

Construction in Fremont is underway

Construction in Fremont, near the intersection of Leary Way NW, NW 36th St, and 2nd Ave NW, started in July 2020.

For the remainder of 2020, crews will:

Stabilize soils for underground construction work
Begin shaft and vault construction

aerial map of the project sitesituated between Leary Way Northwest and the Burke Gilman Trail. The dotted orange line along first avenue Northwest and Northwest 36th Street denotes the pedestrian detour. A small blue line that runs from the project area and across the Ship Canal represents the microtunnel placement. — Construction area map (Click or tap image to enlarge)

What to expect during construction

Crews will generally work between 7 a.m. and 5 p.m., Monday through Friday
- 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 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
Removal of some trees in the project area
Burke-Gilman Trail to remain open except temporary impact during conduit installation (likely one week)

Aerial map of planned road closures and impacts needed for constuction. Single lane or full road closures planned for NW 36th St, 2nd Ave NW, and Leary Way NW — Expected road closures needed for Fremont construction (Click or tap image to enlarge)

Learn more about the Fremont Site

Project elements in Fremont include:

A new 85-ft deep, 32-ft diameter vertical shaft to carry sewage and stormwater into the new storage tunnel
New pipe installation to connect the new shaft to the existing combined sewer system overflow pipe
A new 8-ft diameter tunnel under the Ship Canal to carry flows from Queen Anne to the storage tunnel
A new underground structure to house mechanical and electrical equipment and odor control

Artists Preston Singletary and David Franklin are collaborating on artwork for the Fremont and Queen Anne sites.

To learn more about the Fremont project site, read our fact sheet.

Queen Anne

Construction in Queen Anne is underway

Construction in North Queen Anne, near West Ewing Mini Park and along 3rd Ave W, started in July 2020.

For the first few months, crews will:

Remove trees onsite
Install wheel stops and bollards
Install stormwater control and soil monitoring equipment

aerial map of project site situated along Third Avenue West and West Ewing Street. Green boxes within the project area indicate the following: underground pipes, cabinet, underground facility and drop shaft. A small blue line that runs from the project area and across the Ship Canal to Northwest 36th Street in Fremont represents the microtunnel placement. — Construction area map (Click or tap image to enlarge)

What to expect during construction

Learn more about the Queen Anne site

Project elements in Queen Anne include:

A new 75-ft deep, 20-ft diameter vertical shaft to carry sewage and stormwater into the new tunnel under the Ship Canal
New pipe installation to connect the new shaft to the existing combined sewer system overflow pipe
A new 8-ft diameter tunnel under the Ship Canal to carry flows from Queen Anne to the storage tunnel

Artists Preston Singletary and David Franklin are collaborating on artwork for the Fremont and Queen Anne sites.

To learn more about the Queen Anne project site, read our fact sheet.

Wallingford

Construction activities resume in August 2020

Our contractor installed a screen wall on the northern and eastern sides of the project site at Interlake Ave N and N 35th St this spring. Additional construction activities will begin again in August.

Beginning as early as August 2020, crews will:

Excavate and remove contaminated soils
Install stormwater control and soil monitoring equipment
Remove the existing fence, gate, posts and stairs
Remove existing asphalt, concrete and some trees
Remove existing utilities

aerial map project site situated at the intersection of Interlake Avenue North and North 35th Street. A dark grey line that runs west from the project site along N 35th Street indicates the storage tunnel. — Construction area map (Click or tap image to enlarge)

What to expect during construction

Construction-related noise, traffic, dust, and vibrations
Staging of equipment and construction vehicles at the project site located at 3500 Interlake Avenue N
Sidewalk closure of the east side of Interlake Ave N
Parking restrictions and roadway detours
Northound lane impacts on Interlake Ave N with flaggers present to direct traffic
Single lane closures on N 35th St and Stone Way N for tieback removal and pipe installation
Removal of some trees in the project area

Learn more about the Wallingford site

Wallingford marks the eastern end of the Ship Canal Water Quality Project and the location where tunneling will end underneath N 35th St and Interlake Ave N. Construction will take place on Stone Way N, N 35th St and Interlake Ave N.

Project elements in Wallingford include:

A new 60-ft deep, 30-ft diameter vertical shaft near Stone Way N and N 35th St to convey stormwater and sewage into the tunnel
New pipe installation along Stone Way N and N 35th St to connect the current combined sewer system overflow pipe to the new vertical shaft
Removing tiebacks underneath N 35th St
A new small, above-ground maintenance and odor control building near 3500 Interlake Ave N
New underground structures to house mechanical and electrical equipment, and odor control
Restoration of impacted roadways

Artist Ryan! Feddersen is working to design an art installation at the project site.

To learn more about the Wallingford project site, read our fact sheet.

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.

Getting ready for secant piles in Fremont and Queen Anne

24th Ave NW pier to stay open for now

More art at our construction sites

Click on the project areas to learn more

About the project

Tunnel

Ballard

Construction in Ballard is underway

East Ballard

Construction in East Ballard is underway

Now - Early August 2020*

Aug. - Early Dec. 2020*

Soil stabilization work

Mid - Dec. 2020 Early March 2021*

Shoring installation, diversion structure excavation

March - Sept. 2021*

Diversion structure, vault and drop shaft installation

Sept. 2021 - Jan. 2022*

Complete vault and drop shaft installation, install associated utilities

Late Jan. - July 2022*

Complete vault and drop shaft installation, install associated utilities

Late July - Nov. 2022*

Adit excavation, vent shaft installation, final restoration

Fremont

Construction in Fremont is underway

Queen Anne

Construction in Queen Anne is underway

Wallingford

Construction activities resume in August 2020

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