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?

Construction in Ballard will begin as early as February 20

Starting the week of February 20, crews wil begin installing a 12’ high sound wall, stormwater controls, and dewatering equipment at the Ballard site. For more information, please see a copy of the construction flyer that went out to more than 2,100 businesses and residents near the work site.

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 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

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

Upcoming work

Work is anticipated to start in Ballard in late February 2020. For more details about this upcoming work, please see a copy of the construction flyer that went out to more than 2,100 businesses and residents near the work site.

For the first few months, crews will be:

Installing a 12’ high sound wall
Installing stormwater controls
Installing dewatering equipment
Preparing the site to support heavy machinery. This may include compacting soils, paving asphalt access roads, tree removal, and laying gravel
Installing artwork along the Shilshole Ave NW wall

Heavy equipment will move onto the site in April with the early stages of shaft construction starting in May.

What to expect during construction

Possible one-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 will remain closed through 2024
Trucks and large equipment moving in and out of the work zone
A track-mounted drill to install steel beam fenceposts
Noise typical of a large construction site
Access to all buildings and businesses will be maintained

Future work

Shaft construction (Begin May 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)
Permanent art installation (2024)

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

Work is anticipated to start in East Ballard as early as April 2020.

For the first few months, crews will be:

Removing trees and curbs onsite
Demolishing the sidewalk on NW 45th St
Installing stormwater control and soil monitoring equipment
Excavating and re-locating the Ballard Terminal Railroad tracks
Re-locating an existing waterline
Removing existing asphalt

What to expect during construction

Construction-related noise, traffic, dust and vibrations
Lane closures on NW 45th St between 9th and 11th Ave NW beginning May 2020
Vehicle and pedestrian detours. The Burke-Gilman Trail will temporarily move to the north side of NW 45th St
Some 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

Work is anticipated to start in Fremont as early as April 2020.

For the first few months, crews will be:

Removing trees onsite
Removing an existing sidewalk on NW 36th St and existing utilities
Installing stormwater control and soil monitoring equipment
Removing existing asphalt
Installing a temporary storm drain bypass

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
Vehicle and pedestrian detours. Leary Way NW will remain open with one lane closed for construction
The Burke-Gilman trail will remain open
Increased truck traffic
Parking restrictions
Removing trees onsite

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

Work is anticipated to start in north Queen Anne in July 2020.

For the first few months, crews will be:

Removing trees onsite
Installing wheel stops and bollards
Installing stormwater control and soil monitoring equipment
Re-routing the Ship Canal trail
Removing existing asphalt, concrete and gravel
Removing existing storm drain pipe

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 detour
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

Work is anticipated to start in Wallingford in March 2020.

Crews will be:

Securing the site
Installing the sound wall along the north and east sides of the site

Starting around July 2020

Installing stormwater control and soil monitoring equipment
Removing and replacing the existing fence, gate, posts and stairs
Removing existing asphalt, concrete, and some trees
Removing existing utilities
Excavating and hauling off contaminated soils

What to expect during construction

Public parking restricted onsite by the end of February
Construction-related noise, traffic, dust and vibrations
Potential parking restrictions
Increased truck traffic

Future work

Shaft construction (Late 2020)
New pipe installation (Begin early 2022)
Permanent art installation (Late 2022)

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

Construction in Ballard will begin as early as February 20

Thank you!

Click on the project areas to learn more

About the project

Tunnel

Ballard

Thank you!

Stay in touch

Upcoming work

What to expect during construction

Future work

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

What to expect during construction

Future work

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