The West Seattle Bridge, which opened in 1984, was suddenly closed on March 23 after cracks in several locations on the span were found to have been growing faster than expected. In the ensuing three weeks, the Seattle Department of Transportation (SDOT) has done daily inspections and scrambled to learn more about what caused the cracks and what to do about it. Now it looks as if it will remain closed through 2021 and beyond if repairs are even possible. If not, it means a new bridge would need to be built far sooner than expected.

SDOT Director Sam Zimbabwe said, "We're at the beginning of a difficult conversation" as he briefed the media on the situation. 

The cracks that were increasing at an alarming rate continue to grow, even without traffic, but their growth has now slowed. It's not in danger of imminent failure or collapse and they have determined it's safe for crews to work on it.

If they are able to repair the bridge it would only have an estimated 10 year additional life. That means a replacement for the existing bridge would need to get funded, designed and the work started sometime prior.

But before they can repair the cracked sections, they plan to address a support on the west side of the river, Pier 18. That support structure has what is called a "locked bearing" though Bridge Engineer Matt Donohue said it may only be partially locked. The design for Pier 18 restraint is now underway and bridge shoring and repair design will begin shortly.

That process will be aided by the recruitment of a Technical Advisory panel for peer review. The panel will be comprised of experts in bridge design, marine construction and others who will  look at and help adjust the planning and design process. In late fall the shoring construction will begin and be complete by early Spring 2021.

Many questions remain including whether or not the bridge can be stablized before further deterioration makes repair infeasible. It's unclear if any repairs will require federal permits since they might impact the navigation channel under the bridge.  Repairs might require special fabrication and equipment. And the big question, how will repairs (or replacement) get funded?

Traffic has been an issue of course even during the pandemic caused "stay home" order but the lower bridge which for the first three weeks of closure had seen up to 15,000 cars daily, is now seeing much less traffic because enforcement of the restrictions to freight, transit and emergency vehicles is being enforced. New signage is up, tickets are being written and drivers are getting the message.

The low bridge is also in need of a $5,000,000 fix to address issues with the hydraulics that permit it to lift and swing ou of the way for marine traffic. 

SDOT has also installed a new traffic signal at Highland Park Way SW and SW Holden, improved detour route signage to the 1st Ave South Bridge, connected the signals at the five way intersection for remote monitoring adjustment, and repaved that intersection. They are also looking at additional measures.

A preliminary budget of estimated costs looks like this:

Monitoring $2,000,000

Design $6,000.000

Pier 18 repair construction $1,000.000

Shoring construction $15,000,000

Traffic control and mitigation $3,000,000

Project Management, communications and outreach $1,000,000

Swing Bridge Maintenance $5,000,000

TOTAL  $33,000,000

and this is before any repairs to the bridge are made. Those costs are at this point, unknown.

The full SDOT Powerpoint Presentation can be seen here

King County Councilmember Joe McDermott released a statement about the matter: 

“I am utterly stunned. The City owes us all an explanation on how on earth it let this much deterioration to Seattle’s most used arterial slip by and reach this point.

“The West Seattle bridge plays a vital role not only to the 100,000 people who live on the west side of the Duwamish, but to our entire state’s economy as a thoroughfare for trade and agriculture. This must be every state legislator’s top priority after dealing with the COVID-19 crisis, beginning in any special session that occurs this year. Economic recovery at a state, regional and local level after this pandemic requires a functional West Seattle transportation connection.

“Planning for a full replacement must begin right now, with the state and federal government stepping up to help expedite the process and funding. I’ll be working at the County, through regional collaboration and transit planning, to sort through the pieces this has left us to ease the burden on residents as best we can. This is an all hands on deck situation for leaders in Washington state.”

Both Mayor Jenny Durkan and District 1 City Councilmember Lisa Herbold said they favored some virtual town halls going forward.

Durkan said, "We're going to have to do more of everything," regarding a variety of transportation alternatives for getting into and out of West Seattle.

Seattle City Councilmembers Herbold and Pederson reacted to the news as well. 

“Today we learned from the Seattle Department of Transportation (SDOT) that, while the rate of cracking of concrete under the West Seattle Bridge has slowed, new cracking continues even with no vehicles.  Unfortunately, SDOT now estimates the bridge cannot be made safe for traffic for at least the next 21 months (through the end of 2021). Safety will continue to be the top priority during this infrastructure emergency. SDOT is developing plans to shore up the bridge in advance of the likely extensive repairs. SDOT believes, however, that repairs would extend the life of the bridge for only 10 years.

“The impact of this long-term closure on West Seattle cannot be understated. We will need additional work to manage traffic and mobility for residents. Ensuring access to emergency services and transit will be critical as well. What we are doing now to provide alternate routes will not be sufficient once traffic resumes normal levels.

“We look forward to working with our State and federal governments to identify the funding for both the repairs and the eventual replacement of the bridge, including an expected stimulus package for infrastructure from Congress. This situation also reinforces the importance of renewing the Seattle Transportation Benefit District to provide additional bus service.

“It’s good that SDOT is creating a technical advisory panel to leverage engineering expertise. The City Council’s Transportation & Utilities Committee will require timely updates from both SDOT and the technical advisory panel.  We will also pursue Legislative Department participation on the technical advisory panel to increase oversight of the complex solutions.”