Reducing sewer overflows by 2025

Welcome to the Ship Canal Water Quality Project website! We’re happy you’re here. To learn about the project and work in your neighborhood, scroll down or click on a project area below.

What’s happening now?

Thank you!

Thank you to all who attended our Ballard drop-in session on Dec. 11, 2019, to learn more about construction in 2020. If you were not able to attend, we have uploaded a PDF version of the meeting boards for you to read at your leisure.

We appreciate the nearly 500 people who took time to fill out our survey on Ballard's 24th Ave NW street end designs. The survey is now closed. Stay tuned for next steps!

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 overlow 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-inch 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 early 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.

Image comparing the Ship Canal Storage Tunnel size with other tunnels around Seattle. (Click or tap image to enlarge)

Learn about ground monitoring

Ballard

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
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

Thank you!

We appreciate the nearly 500 people who took time to fill out our survey on Ballard's 24th Ave NW street end designs. The survey is now closed. Stay tuned for next steps!

Excavators and construction crews prepare the future Ballard construction site at Shilshole Avenue Northwest and 24th Avenue Northwest on a sunny day. — Future Ballard construction area at Shilshole Ave NW and 24th Ave NW. (Click or tap image to enlarge)

Stay in touch

Richard Fernandez, PE - Project Manager
richard.fernandez@seattle.gov
206-684-0285

Learn more about the Ballard site

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

Public engagement about the site design, especially the 24th Ave right of way, is expected to begin in November 2019. Stay tuned!

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)

Learn more about construction work in Ballard

Current work

Soil remediation
Utility relocation
Sewer outfall pipe replacement

Upcoming work

Shaft construction (Begin early 2020)
Tunneling (Begin mid-2021)
New pipe construction along NW 56th St, 28th Ave NW and 24th Ave NW (Begin 2022)
Pump station construction (Begin 2023)
Art installation (2024)

The timeline above is an estimate. As the tunneling contractor comes onboard and develops their schedule, the timing of upcoming work may change. We'll be sharing information soon. Stay tuned for updates!

Current construction impacts

Construction-related noise, traffic, dust and vibrations
Closure of 24th Ave NW Pedestrian Pier through 2024
Increased truck traffic along 24th Ave NW and Shilshole Ave NW
Parking restrictions along 24th Ave NW

An aerial map of the projected Ship Canal Water Quality Ballard Project site. The projected project site is situated between 24th avenue North West and Shilshole Avenue Northwest. Project areas are shown as purple boxes, and a yellow line within the box indicates the 24th avenue pier. 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. — Ballard project site. (Click or tap image to enlarge)

East Ballard

Construction in East Ballard will take place on NW 45th St between 11th Ave NW and 9th Ave NW and on 11th Ave NW just south of NW 45th St.

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 sewer system to the new vertical shaft and storage tunnel
A new below-grade structure to house mechanical and electrical equipment and odor control

A four-way intersection near the future site of East Ballard vertical shaft at Northwest 45th Street and 11th Avenue Northwest. — Future site of East Ballard vertical shaft at NW 45th St and 11th Ave NW. (Click or tap image to enlarge)

Stay in touch

Stephanie Secord, PE - Project Manager
stephanie.secord@seattle.gov
206-386-9778

Learn more about construction work in East Ballard

Upcoming work

Construction will begin as early as 2020. We are currently working with our contractor to determine the project’s construction schedule.

We’ll be sharing construction information soon. Stay tuned for updates!

What to expect during construction

Construction-related noise, traffic, dust and vibrations
One lane closure on 11th Ave NW between the Fred Meyer entrance on 11th Ave NW and NW 45th St for approximately 3 to 6 months
Full closure of NW 45th St between 9th and 11th Ave NW for approximately 15 months, including detours for vehicular traffic, pedestrians, and the Burke-Gilman Trail to the north side of NW 45th St
Possible nighttime work
Staging of construction vehicles and equipment in the right of way
Increased truck traffic
Parking restrictions

An aerial map of the projected Ship Canal Water Quality East Ballard Project site. The projected project site is situated along Northwest 45th Street and is between 11th Avenue North West and 9th Avenue Northwest. Project areas are shown as purple boxes, and a yellow line within the box indicates the 24th avenue pier. 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. — East Ballard project site. (Click or tap image to enlarge)

Fremont

Construction in Fremont will take place near the intersection of Leary Way NW, NW 36th St and 2nd Ave NW.

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 sewer system
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.

A red brick building beside a tree with orange leaves in the future site of Fremont vertical shaft at Leary Way Northwest and Northwest 36th Street. — Future site of Fremont vertical shaft at Leary Way NW and NW 36th St. (Click or tap image to enlarge)

Stay in touch

Stephanie Secord, PE - Project Manager
stephanie.secord@seattle.gov
206-386-9778

Learn more about construction work in Fremont

Upcoming work

Construction will begin as early as 2020. We are currently working with our contractor to determine the project’s construction schedule.

We’ll be sharing construction information soon. Stay tuned for updates!

What to expect during construction

Construction-related noise, traffic, dust and vibrations
Closure of NW 36th St between Leary Way NW and 3rd Ave NW for up to 15 months
Closure of 2nd Ave NW between Leary Way NW and Canal St for approximately 9 months
Temporary roadway detours on streets adjacent to the project area. Leary Way NW will remain open with one lane closed for construction.
Increased truck traffic
Parking restrictions near work zone
Removal of some trees in the project area

An aerial map of the projected Ship Canal Water Quality Fremont Project site. The projected project site is situated between Leary Way Northwest and the Burke Gilman Trail (which is denoted with a green dotted line). Project areas are shown as purple boxes, green boxes within the project area indicate the following: electrical generator with fence, underground facility and drop shafts. A grey square in the middle of the project area represents an existing King County Fremont Siphon building. 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. — Fremont project site. (Click or tap image to enlarge)

Queen Anne

Construction in North Queen Anne will take place near West Ewing Mini Park and along 3rd Ave W.

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 sewer system
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.

A yellow excavator surrounded by orange cones is situated next to trees at the future site of Queen Anne vertical shaft at the end of W Ewing St from across the Ship Canal in Fremont. — Future site of Queen Anne vertical shaft at the end of W Ewing St from across the Ship Canal in Fremont. (Click or tap image to enlarge)

Stay in touch

Stephanie Secord, PE - Project Manager
stephanie.secord@seattle.gov
206-386-9778

Learn more about construction work in Queen Anne

Upcoming work

Construction will begin as early as 2020. We are currently working with our contractor to determine the project’s construction schedule.

We’ll be sharing construction information soon. Stay tuned for updates!

What to expect during construction

Construction-related noise, traffic, dust and vibrations
Increased truck traffic along W Nickerson St and 3rd Ave W
Parking restrictions and roadway detours
Ship Canal Trail detours
Protection or removal of some trees
Temporary closures of West Ewing Mini Park

An aerial map of the projected Ship Canal Water Quality Queen Anne Project site. The projected project site is situated along Third Avenue West and West Ewing Street. Project areas are shown as purple boxes, and a green dotted line that runs through the project area indicates the Ship Canal Trail. 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. — Queen Anne project site. (Click or tap image to enlarge)

Wallingford

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 sewer system to the new vertical shaft
A new small, above-ground maintenance and odor control building near 3500 Interlake Ave N

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

A fence encases the future site of Wallingford vertical shaft at North 35th Street and Interlake Avenue North on a cloudy day. — Future site of Wallingford vertical shaft at N 35th St and Interlake Ave N. (Click or tap image to enlarge)

Stay in touch

Kelsey Hinsperger, PE - Project Manager
Kelsey.Hinsperger@seattle.gov
206-684-0411

Learn more about construction work in Wallingford

Current work

Development of the new pipe design that will connect the shaft to the existing sewer system

Upcoming work

Shaft construction (Begin early to mid-2021)
Temporary art installation (Late 2019)
Site remediation (Begin early to mid-2021)
New pipe installation (Begin early 2022)
Permanent art installation (Late 2022)

The timeline above is an estimate. As the tunneling contractor comes onboard and develops their schedule, the timing of upcoming work may change. We’ll be sharing construction information soon. Stay tuned for updates!

What to expect during construction

Construction-related noise, traffic, dust and vibrations
Potential parking restrictions
Lane closures on Stone Way N and detours of N 35th St
Potential wayfinding and detour signage for bicycles and pedestrians on Stone Way N and near adjacent intersections
Staging of equipment and construction vehicles in the right of way
Increased truck traffic
Possible tree removal and protection

An aerial map of the projected Ship Canal Water Quality Wallingford Project site. The projected project site is situated at the intersection of Interlake Avenue North and North 35th Street. The Project area also includes conveyance pipe alignment which runs along North 35th Street and Stone Way North and stops at the intersection of Stone Way North and North 34th Street. Project areas are shown as purple boxes, and green boxes in the project area indicate drop shaft and underground structure. An orange box in the project area denotes an electrical building. A dark blue line that runs west from the project site along N 35th Street indicates the storage tunnel. — Wallingford project site. (Click or tap image to enlarge)

An animated image of the projected Wallingford project site shows a person riding their bike along the intersection, two people chatting on the sidewalk and a person walking their dog on a sunny day. A black fence encases the project site. — Rendering of future Wallingford site. (Click or tap image to enlarge)

Learn more about the Wallingford site

Reducing sewer overflows by 2025

Thank you!

Click on the project areas to learn more

About the project

Tunnel

Ballard

Thank you!

Stay in touch

Current work

Upcoming work

Current construction impacts

East Ballard

Stay in touch

Upcoming work

What to expect during construction

Fremont

Stay in touch

Upcoming work

What to expect during construction

Queen Anne

Stay in touch

Upcoming work

What to expect during construction

Wallingford

Stay in touch

Current work

Upcoming work

What to expect during construction

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