Archived Project Updates
Our 8-foot diameter tunnel boring machine has finished its journey to Queen Anne!
On Groundhog Day (2/2/23), our 8-ft diameter tunnel boring machine (TBM) reached its destination in Queen Anne. To prepare for the TBM breakthrough, our engineers filled the Queen Anne shaft with water to maintain the pressure balance of the TBM face and the surrounding groundwater. Our TBM operators successfully drove toward and broke through a predetermined circular target in the shaft wall with an extremely high level of precision, down to the millimeter. Check out our Flickr albums for more pictures of the TBM breakthrough and recovery.
The Wallingford Conveyance Project: Coming to you Soon!
SPU needs to install new pipes along Stone Way N and N 35th St to connect Wallingford’s existing combined sewer outfall pipe to the future storage tunnel. To install these new pipes, there will be full and partial road closures and parking restrictions in the area. The first phase of work will close Stone Way N starting in early 2023 for at least one year.
Detours will shift over the course of the project. As early as January 23, Puget Sound Energy will be removing parking spots on Stone Way N, between N 34th St and N 35th St, to complete necessary utility work. As early as January 30, there will be a full closure of Stone Way N between N 34th St and N 35th St to vehicle traffic. A two-way bike lane and the sidewalk on the east side of Stone Way N will be maintained.
How to get around during the full closure of Stone Way N:
The Wallingford Conveyance Project: Coming to you Soon!
As soon as January 2023, crews will begin installing a large pipe along Stone Way N and N 35th St, and a deep diversion structure near the intersection of Stone Way N and N 34th St. This pipeline will divert polluted stormwater and sewage into the storage tunnel. This work will entail some long-term and intermittent road closures. Learn more about the Wallingford Conveyance project and its impacts in the Wallingford neighborhood section below.
Connect with your Ship Canal through the Saltwater Soundwalk
Our friends over at the Seattle Office of Arts & Culture, in collaboration with artists Jenny Asarnow and Rachel Lam (Anigiduwagi enrolled Cherokee Nation), have been thoughtfully curating a podcast. Saltwater Soundwalk is a new podcast that explores our relationships and responsibilities toward the Salish Sea and connecting waters, centering on Indigenous Coast Salish voices and language. Learn more about the Saltwater Soundwalk via this blog post or on the Ship Canal Water Quality art page, and listen to the full collection wherever you get your podcasts.
MudHoney has arrived in East Ballard!
It’s an exciting moment in the world of the Ship Canal Water Quality Project: MudHoney, our 18-ft diameter tunnel boring machine (TBM), officially arrived at the East Ballard project site in early August! MudHoney has been grinding along for a while now, and this is one of several planned maintenance stops to check MudHoney’s cutterhead along the route.
MudHoney will be paused for several weeks while this inspection and maintenance takes place. Check out our listserv for more information about what takes place during these maintenance stops.
11th Ave NW is down to one lane
Crews are building the diversion structure and conveyance pipes on 11th Ave NW that will eventually connect the existing sewer and stormwater pipe to the storage tunnel. To allow crews to perform this work,11th Ave NW, just south of NW 45th St, has been reduced to a single, narrow lane. Flaggers are directing northbound and southbound traffic as well as bicyclists during daytime working hours, and traffic signals will direct traffic during non-working hours. Directional signage is also in place. For safety, bicyclists should either dismount or cross train tracks at a 90-degree angle. Please use extra caution in wet weather as ramps may be slippery.
The single lane with flaggers will be in place until late November and likely need to resume in early 2023. We are hoping to open it up for the busy holiday season.
As a reminder, NW 45th St remains closed to traffic between 11th Ave NW and 9th Ave NW. Burke-Gilman Trail users continue to be detoured to the north side of NW 45th St through the project area.
Ship Canal Trail detour changing course for the summer
Hello Ship Canal Trail users, the current Ship Canal Trail detour that has been in place for the past two years near Ewing Park, adjacent to Seattle Pacific University, will be temporarily removed as early as late May 2022. The trail will move back to its original location for the summer of 2022. Our contractor will be working on both sides of the trail so please be aware of your surroundings.
The current detour route will be reinstated this fall. After being reinstated, this detour will remain for the duration of construction in this location, likely until mid-2023.
MudHoney v. Megaboulder
In early May, MudHoney, our 18-foot diameter TBM, was tunneling eastward and ran into an enormous boulder. Although our designers and engineers had planned for a few boulders along the route, this one was exceptionally large for our area—about 10-feet tall. We’re not-so-fondly calling it Megaboulder.
We paused tunneling to check on MudHoney and get more information about boulder size and strength. MudHoney passed the overall health check, but we did have to replace and repair some cutterhead tools to better equip it for grinding through a solid piece of rock—a difficult task to complete while under 70 feet of water pressure, and in a space only 3 feet wide inside the very front of the TBM.
On Friday, May 27, we successfully broke through. Tunneling has resumed at its original pace.
Long story, short: We persevered. MudHoney beat Megaboulder. For more information, check out our June 2 program email.
Intermittent lane reductions on Leary Way NW through approximately May 2022 [updated on 4/12/22]
Any new built structures need to have solid ground to live on. Jet grouting, one of many effective ways to stabilize and strengthen soil, is the way we will prepare the soil for upcoming Fremont construction.
To complete this work, we will need to close some traffic lanes on Leary Way NW from November through May 2022. Two lanes will always remain open (one lane in each direction), and when work is not taking place, we will leave all lanes open when possible. Access to all businesses will be maintained. If you are commuting through this area, consider taking our optional detour during this work.
April 12, 2022 update:
The work related to soil stabilization in Leary Way NW is complete and the contractor has completed pavement restoration on the south half of the roadway. Starting Monday April 18, the contractor plans to shift traffic to the south half of the roadway to begin utility restoration work in the north half of NW Leary Way. This work will include intermittent closures over the next few weeks. NW Leary Way is expected to be fully reopened by mid-May.
MudHoney has resumed tunneling
After a planned pause, MudHoney, our 18-ft diameter tunnel boring machine (TBM), resumed tunneling on February 7. Before starting MudHoney, we sent our engineers and workers inside the excavation chamber under compressed air to check on the condition of the cutting tools. Pressurized air allows workers to safely enter the cutterhead chamber without groundwater entering the TBM. The pressure here is equivalent to recreational scuba diving at an 80-ft water depth. There are several more maintenance stops planned along the way.
For more information about how we keep MudHoney on track when we can’t “see” where we are going, take a look at one of our previous listservs.
Building underground structures throughout the project corridor
Most of our city’s wastewater system is underground, which means a lot of digging during a project like this. To build a system that will keep sewage mixed with stormwater from entering the Ship Canal during heavy rains, there are supporting structures we need to construct in addition to our large and awesome storage tunnel (thanks for all the work so far, MudHoney!). In 2022, we’ll be building these supporting structures at our East Ballard, Queen Anne, and Fremont sites. They include vaults, drop shafts and diversion structures.
Check out our glossary for a deep dive into these structures and other more technical elements of our project!
MudHoney pausing while crews build a rail system
MudHoney, the 18-ft storage tunnel boring machine (TBM), has tunneled approximately 880 feet. MudHoney has reached a planned pause to switch from the conveyor belt system of removing spoils to the rail system (see previous listserv for more information) and for trailing gear installation.
Keeping water service going during construction
Through the end of the year, crews will be installing temporary water pipes at our East Ballard and Fremont sites. These temporary pipes will be above ground or in a shallow trench near the project site. Crews will be working underground around the existing water pipes and installing the temporary bypass pipe allows them to do the work needed without shutting off water service. Check out this video to find out more about how a bypass pipe is connected.
Ballard Pump Station: Construction to start in 2023
The Ballard Pump Station will hold mechanical and electrical equipment to pump flows out of the storage tunnel and send it to treatment at King County’s West Point Wastewater Treatment Plant. The 90% design was approved by the Seattle Design Commission in early October. Construction will begin in 2023.
The pump station building will be an 80-ft tall, illuminated tower, inspired by Ballard's shipyards and maritime industry. The site includes artwork by Jeffrey Veregge, from the Port Gamble S’Klallam Tribe, that celebrates the Coast Salish heritage and historical use of the area. Interested in knowing more about the pump station? Watch our introductory video below and learn more about these future improvements through our Flickr album.
Check out our latest artwork!
The latest temporary artworks from FLOW are now on display in Fremont, Ballard, Wallingford and East Ballard. Enjoy the start of Fall with a stroll through your neighborhood to look for these pieces and learn about their stories. You can learn more about the artists and their art on our art page.
Our tunnel boring machines have launched!
We are so excited to announce that both of our tunnel boring machines (TBMs) have begun tunneling. MudHoney, our 18-ft storage tunnel TBM, began its 2.7-mile journey to construct a storage tunnel from Ballard to Wallingford. Our 8-ft conveyance tunnel TBM will take a little over three months to dig from Fremont to Queen Anne and connect Queen Anne’s wastewater basin to the larger storage tunnel being built by MudHoney.
If you want to take a break and get out some coloring pencils or markers, check out our coloring sheets!
In East Ballard 11th Ave NW reduced to single-lane this summer
As early as Tuesday, July 20, 11th Ave NW will reduce to single lane traffic. Traffic will be controlled by flaggers during the day and traffic lights at night. During this time, crews will excavate for pipe and structure work in 11th Ave NW.
June and July 2021
Our 8-ft conveyance tunnel boring machine has arrived in Fremont!
Our 8-ft conveyance tunneling boring machine (TBM) has arrived in Fremont. This smaller TBM will dig from Fremont to Queen Anne, connecting Queen Anne’s wastewater basin to the larger storage tunnel. It will sit in the Fremont shaft until tunneling begins this month. To learn more, check out the Fremont section of our website.
Water main work in East Ballard in July
Crews will perform a water main bypass this summer that will require a short, temporary water outage. If your service will be impacted, you'll receive a door hanger with more information.
MudHoney is getting ready to dig!
In April, our crews lowered MudHoney, our 18-ft diameter storage tunnel boring machine, into the shaft in Ballard, where its tunneling journey will begin later this summer. Check out our new video, showing what it takes to lower MudHoney into the tunnel shaft in different pieces. Each piece can weigh between 25 and 150 tons!
2nd Ave NW closure between Leary Way NW and Canal St in Fremont coming up
Starting as early as mid-May, 2nd Ave NW will be closed to vehicle and pedestrian traffic to conduct sewer and diversion structure work. This closure is expected to last until the end of the year. For more information, please take a look at our construction flyer.
Meet our Tunnel Boring Machine (TBM), MudHoney!
We received over 1,200 TBM name submissions from the community, and over 30,000 votes! After tallying all the votes, we are thrilled to announce that our TBM is now named MudHoney!
Thank you for helping us #NameThatTBM!
This summer MudHoney will begin digging a 2.7-mile long, 18-ft 10-in diameter storage tunnel to reduce Seattle’s sewer overflow by 2025! Sign up for our project email list to learn how to follow along as MudHoney digs under our feet. MudHoney has already had a chance to meet the band it was named after, take a look at this video to see how that went!
Devin Finley - Tunnel Boring Machine
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.
We are assembling the Tunnel Boring Machine in Ballard!
We're busy assembling the tunnel boring machine (TBM) on our Ballard site, which will begin its 2.7-mile journey later this summer. Keep an eye out for its official name, informed by community input, this spring!
New art installations are being added to our construction sites!
In February and March 2021, four new artists will install temporary art installations along our construction sites. Check out the art tab to learn more.
Stormwater permit request for Wallingford Conveyance project
We have requested a Construction Stormwater General Permit for the Wallingford Conveyance project, which will install a 213-ft long, 36-in diameter pipeline along Stone Way and a 412-ft long, 42-in diameter pipeline along N 35th St to convey polluted stormwater and sewage from the Wallingford neighborhood into the storage tunnel. Stormwater from construction sites can carry debris and chemicals to close-by waterways and this permit will specify mitigation requirements to be implemented at our construction site to help reduce water pollution. Department of Ecology will monitor the performance of our mitigation measures through inspections and water quality assessments.
The 30-day public comment period for Department of Ecology began on February 23, 2021.
Thank you for submitting Tunnel Boring Machine (TBM) naming ideas!
Due to the overwhelming response (we received over 1,200 submissions!), we are pushing back the voting start a few days to allow for more time to be thoughtful in our selection process. Ship Canal team members will select their favorite submissions and put them to a public vote! Stay tuned for more information.
Be sure to check back in or sign up for our project email list for updates!
Pieces of the Tunnel Boring Machine have started to arrive in Ballard
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 at our Ballard site over the next few months. The photos below show crews unloading a section of the lower shield last week, and then what the machine will look like fully constructed.
Construction progress in 2020
Construction is underway at all five project sites. As of December 2020, the secant pile wall in Queen Anne is complete, Fremont’s is nearing completion, and we are breaking ground on this activity in Wallingford. Soil stabilization in East Ballard continues, and we just reached a huge project milestone in Ballard - completing the concrete pour for the 14-ft thick, 87-ft wide shaft floor. We are thankful for your patience and support as we continue this essential work to reduce combined sewer overflows in our waterways by 2025.
Visit our Flickr page to see photos of recent construction activities.
The Tunnel Boring Machine is headed to Seattle and will arrive in early 2021!
Our Tunnel Boring Machine has left Germany on a ship and is on its way to Seattle! Over the next few months this machine will make its way to the shores of the Puget Sound where it will be prepped to start boring a 2.7-mile tunnel from Ballard to Wallingford. Watch this video to learn more about the machine as it begins its journey west!
Seattle artist taking T-shirt donations through Dec 31
In Spring 2021 we will be installing a new round of temporary art installations along our construction sites. Interested in participating? Seattle artist Janelle Abbott is taking t-shirt donations now through Dec. 31 to create her piece in Wallingford. Learn about how you can donate t-shirts for the installation.
Secant pile wall construction begins in Queen Anne
Starting November 9, 2020, crews began construction on the secant pile wall at the Queen Anne site. This work is expected to be complete in late-December. A secant pile wall is 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, rebar cages and trucks traveling and out of the site.
- Noise and vibration from the drilling machine. You may be able to feel the vibration which is expected. We are monitoring vibration levels on site to ensure they are within allowable levels.
- The West Ewing Mini Park parking lot to be closed. This closure is anticipated to last through mid-2023.
- A localized Ship Canal Trail detour through summer 2022. You can view the detour here.
Vertical shaft excavation started in Ballard
In early October, crews began excavation of the 120-ft deep, 87-ft wide vertical shaft at the Ballard site (see photo from the week of Oct. 5). This work is expected to be complete in mid-November. Once excavation is complete, the contractor will construct the interior walls with reinforced concrete, including the 14-ft thick base slab. The shaft will be the launch site for the tunnel boring machine in 2021.
This shaft will ultimately be part of the future Ballard pump station. The pump station will be used to drain water from the storage tunnel and send the water to the West Point treatment plant. It will also be used to provide maintenance access to the storage tunnel.
Meet the artists for our construction sites
Our first round of temporary art is now installed in four neighborhoods. Check out the new videos from our artists, sharing their background and inspiration for their installations, on the art tab.
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. 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.
We’re on Flickr!
Seattle Public Utilities is now on Flickr! Check out albums uploaded this week highlighting temporary art and recent construction activities.
Queen Anne trail detour update
We heard some community concerns about our previously proposed trail detour, so we worked with our contractor to move it. As early as mid-August, the trail will be moved just south of the existing trail, through the adjacent parking lot near Seattle Pacific University and West Ewing Mini Park.
The detour will be about 200 feet long and will be on a fully paved, 8-ft wide asphalt path that allows for two-way bike traffic. Trail users will be expected to yield to traffic on 3rd Ave W (same as now). This detour will remain in place until mid- to late 2022.
Keep a look out for signs on the trail. We will continue to update you on detour timing and any changes to detours via our project email list.
Bringing art to our construction sites
Did you know that there are both temporary and permanent artworks as part of the Ship Canal Water Quality Project?
There are two temporary artworks currently on display, including new art by Kalee Nelson and Crystal Christopherson that was installed on our Wallingford screen wall in late July. Elevating awareness of Missing Murdered Indigenous Women is the key goal of this temporary installation that includes a large-scale mural featuring traditional formline design of orcas.
Two more temporary artworks will be installed later this summer. Learn more about these pieces and the others that will be installed on our new Art page!
Construction underway in all neighborhoods!
As you scroll down this page, you’ll note that construction is going on in all five neighborhoods. For more detailed information, take a look at the fact sheets in our Project Library. We also encourage you to sign-up to our project email for any updates or changes to these schedules.
Heads up trail detours coming!
The weather has been perfect for enjoying the trail and we want to make sure your trip goes as smoothly as possible. Here are some things you should know about upcoming trail detours.
East Ballard detour: As early as July 6, the Burke-Gilman Trail will be detoured from the south side of NW 45th St to the north side of NW 45th St between 11th Ave NW and 9th Ave NW, next to Fred Meyer. Two-way traffic will be maintained and flaggers will be on-site during the daytime. You will be directed to cross at a 90-degree angle to safely traverse the railroad tracks. This detour will remain in place until early 2023.
Queen Anne detour: As early as July 20, the Ship Canal Trail will be detoured onto 3rd Ave W, W Nickerson St and W Cremona St. This detour will remain in place until mid-2022.
Keep a look out for signs on the trail. As work progresses we will continue to update you on detour timing and any changes to detours will be shared via our project email list. Also, feel free to give us a call with any comments or suggestions on how to get the word out.
Construction starting in East Ballard and Fremont
In May and June, work will begin in the following locations:
- East Ballard: Work 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 (near Fred Meyer)
- Fremont: Work will take place near the intersection of Leary Way NW, NW 36th St and 2nd Ave NW
Work at both sites will involve above- and below-ground construction to build new pipes and vertical shafts to connect the current combined sewer system overflow pipes to the new storage tunnel. During the first few months of work, crews will set up fencing, remove trees, curbs and existing asphalt, and stabilize soils to prepare for underground construction.
Slurry wall construction begins in Ballard!
The slurry wall is a reinforced-concrete circular structure that will allow for safe excavation of the vertical shaft, which will ultimately bring stormwater and sewage flows into the new storage tunnel. The vertical shaft will also be the starting point for the tunnel boring machine that will begin its journey next year.
This work includes putting rebar steel cages inside 210-ft deep trenches and filling them with concrete. You can expect a large uptick in equipment and trucks going in and out of the work site to support this construction.
It's a bird! It's a plane! It's a ...crane!
If you’re passing by our Ballard site, take a look up and check out the 250-ton crane towering over the work zone! The crane arrived from the mid-west in early April and crews have been busy assembling this massive piece of equipment.
The crane’s first assignment is to assist with slurry wall construction, one of the earliest phases for vertical shaft construction. It will be an 87-ft diameter, 210-ft deep, 4-ft thick reinforced concrete circular structure which will keep walls from collapsing during shaft excavation. You may experience additional noise and vibrations associated with this work.
Eventually, when the shaft is complete, we'll launch our tunnel boring machine through it!
Ballard’s 24th Ave NW Pier is open to the public!
We are pleased to share that the 24th Ave NW Pier has been temporarily re-opened to the public!
It will close again in late August to support construction activities, so we hope you get a chance to enjoy it while the sun is out this summer. Next year, crews will use the pier to carry tunnel spoils away by barge, which will reduce the number of truck trips needed and help mitigate traffic impacts.
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 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!
Take our survey on Ballard's 24th Ave NW street end designs through Jan. 10 2020
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 would also love to hear your thoughts on the designs for the 24th Ave NW street end in Ballard. Please complete this survey available through Jan. 10, to provide feedback. We appreciate you taking the time to help us learn more about what you want to see once construction is complete!
View archived survey page.
November Public art update
Over the summer, our Wallingford artist, RYAN! Feddersen, asked community members what water means to them. Their responses inspired her to create temporary artwork along the Ship Canal alignment that is activated by rain. Next time you’re walking along the tunnel alignment, take a look at the sidewalk and learn about why your neighbors value water. The installations are expected to last between four and six months.
Early work at our Ballard site is underway!
Crews are preparing our Ballard site for tunneling. Here are the activities they’re working on:
- Replacing the 24th Ave NW Pier to prepare for removing tunnel spoils by barge
- Replacing the outfall pipe under the pier
- Relocating utilities
- Removing contaminated soils from the shaft site
Local artist Vaughn Bell is leading several artists to install permanent artwork along the storage tunnel alignment across all five neighborhoods. Artists will use a wide variety of mediums, materials and techniques to make our underground infrastructure and regional water quality improvements more visible.
Some goals of the Ship Canal public art include:
- Increasing public awareness of the function of water quality projects and infrastructure
- Making an invisible system more visible
- Connecting people to the flow of water in their city, their home and local ecology
- Creating meaningful, inspiring and thought-provoking art experiences in the public realm
Artwork will include both permanent and temporary installations.