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The fastest path: Building on months of stabilization work, major repairs slated for West Seattle High-Rise Bridge

Mayor Durkan chooses repair over replacement, pushing for bridge reopening in 2022

Mayor Jenny Durkan, SDOT Director Sam Zimbabwe, CTF co-chairs Paulina Lopez and Greg Nickels, and SDOT engineer Kit Loo stand on the West Seattle Bridge and discuss.

The Decision

Today, Mayor Jenny A. Durkan announced that she has instructed the Seattle Department of Transportation (SDOT) to restore travel across the Duwamish by repairing the West Seattle High-Rise Bridge. SDOT has nearly completed Phase I of this two-part repair process, as the stabilization work concludes in December. She also directed SDOT to continue early design work for an eventual replacement of the bridge.

Watch this morning’s full announcement here.

“After weighing a number of factors and listening to the experts, neighbors, and small businesses in West Seattle and impacted communities, we will move forward with repairing the West Seattle Bridge to restore mobility as soon as possible. Safety, jobs, certainty, speed to resume mobility, costs, and community input were all key factors in my decision to repair. This corridor is critical to our economy and our residents and the other options could not realistically be done in a reasonable timeframe, would cost significantly more money and provided no more capacity for transit or other modalities. While all options have risks, repair will get West Seattle reconnected the fastest and funding is more certain.  In the last five months, SDOT has worked to stabilize the bridge through repairs, and work has already begun on the longer-term repair plan so traffic can resume by mid-2022.”  

Mayor Durkan

We are all still reeling from the impacts of COVID-19. As we fend off the virus and prepare to build back stronger than before, we need an equitable recovery. That requires mobility and connectivity for all of the City. We cannot leave West Seattle and the surrounding communities behind, which is why the speed and urgency that comes with repair are of the utmost importance.

From the beginning, the Mayor made clear that her goal was to identify the pathway that provides the highest degree of certainty for a safe and rapid restoration of travel with the lowest level of impact to communities in and around the Duwamish Valley, the city, region, and state. After close consultation and analysis from SDOT’s structural team, members of the Community Task Force, SDOT’s Technical Advisory Panel composed of leading experts in their fields, and countless others, it became clear that repair is the best way to safely restore this critical connection as quickly as possible.

The Mayor’s rapid decision to initiate stabilization repairs in March means we are already months down the repair pathway selected today, ensuring that not a moment of forward-progress has been lost. Today’s announcement continues work that has been happening on, under, and inside the bridge six- to seven-days-a-week.

“The Mayor’s decision to repair the West Seattle High-Rise Bridge continues work that has been happening on, under, and inside the bridge since March. Through these ongoing stabilization repairs, we are already months down this pathway. Not a moment has been lost to restore travel across the Duwamish for communities in and around West Seattle as the Mayor consulted our structural team at SDOT, members of the Community Task Force, our outside technical experts, and others to arrive at the best path forward to safely restore this critical connection as quickly as possible. SDOT stands ready to drive this repair forward and reconnect West Seattle by 2022. It will take partnership and courage at all levels of government to restore travel quickly and plan for an eventual replacement that leverages all opportunities for improved connectivity, but I know, together, we can continue on this path and on this timeline.”

Seattle Department of Transportation Director Sam Zimbabwe

SDOT and consultant WSP will continue stabilization efforts and design the final phase of the repair work in the coming months, with an eye toward reopening the West Seattle High-Rise Bridge in 2022. The design consultant, HNTB, will also move forward with a Type, Size & Location study that will lay the groundwork for future replacement.

Why Repair, not Replace

Mayor Durkan and engineers in a dark girder of the West Seattle High-Rise Bridge. People are wearing headlamps which light some of the girder made mostly of concrete.
Mayor Durkan visited the West Seattle High-Rise Bridge, and saw firsthand the stabilization work underway while hearing from bridge engineers. Photo Credit: Tim Durkan.

Urgency, speed, community voices, and the challenges of securing the full funding needed in record time led the Mayor to this critical repair decision.

So many technical factors shaped this decision through careful data collection and analysis, a comprehensive cost-benefit analysis, complex structural modeling, in-person inspections and monitoring. At the end of the day, however, it was the voice of community that truly shaped this outcome.

The Community Task Force is exactly what it sounds like – people from across the region showing up to voice and represent the many ways the High-Rise Bridge closure has impacted the lives of everyday people in their communities, what’s most important to them, and why. It’s not one voice or one opinion. It’s many. That is exactly what the Mayor asked for and heard, ensuring she did not lose the nuance and complexity she faced in making this decision and that the people – those whose lives have been upended by this closure – were at the very center of it all.

In every discussion it was clear that the community – from small business owners to families to industry – wanted a path forward that provided the safest, fastest solution to reconnect West Seattle that balanced the highest degree of certainty with the lowest level of impact to communities in and around the Duwamish Valley, the city, region, and state. Both pathways – repair now and replace later, or pivoting immediately to replacement – had strengths, weaknesses, risks, and opportunities when measured against those goals, and the Task Force brought them all into stark relief for the Mayor’s consideration.

For the Mayor, it initially seemed that the replacement pathway held the most promise. That only grew as new and innovative methods were introduced that could expedite the construction of a new center span replacement. In the end, however, it became clear that any replacement pathway might not provide the urgency and speed that our current context demands. Again, to build back stronger than before the pandemic, we need to restore this critical connection as quickly as possible.

Funding uncertainty was also a hurdle. We have incredible partners and representatives in Washington, DC, but they are fighting an uphill battle to fund the infrastructure maintenance backlog across the country.

We are making decisions and investments today for a better, stronger, and more resilient tomorrow. Selecting the repair pathway now gives us the mobility our recovery demands the soonest, while we also make progress for the future replacement of the High-Rise Bridge by pursuing the Type, Size & Location study. Repairing the West Seattle High-Rise Bridge now gives us time to be certain that when we do move towards replacement, that pathway truly is rapid and takes full advantage of any opportunities for improved mobility.

Not a moment lost in efforts to repair and reopen the West Seattle High-Rise Bridge

The Mayor and SDOT’s number one goal is to preserve public safety and protect lives. That is why we made the decision to immediately close the West Seattle High-Rise Bridge when cracking rapidly accelerated in March, and why we immediately began to implement the critical stabilization work that has been happening on, under and inside the bridge, six- to seven-days-a-week.

Through these ongoing stabilization repairs, the Mayor not only prevented significant potential harm to the public, but also preserved the integrity of the bridge so that a repair pathway remained viable and proactively moved us months down this pathway. We are now within weeks of completing the first phase of this critical repair work.

These efforts reached two key stabilization milestones in November: releasing damaged bridge bearings at the Pier 18 column and the installation and tightening of post-tensioning steel cables inside the bridge girders to further support the main bridge arch.

More detailed explanations of this work, along with images and videos, are available here:

To build on these stabilization efforts, SDOT has directed WSP to complete the design for the full bridge repair, work that could not be done until WSP could draw from – and have Part II of the repair work informed by – the nearly-complete stabilization work. The ability to complete this work is also contingent upon observing a winter thermal cycle to see how the newly-installed stabilization measures respond to the cold weather, particularly sub-freezing temperatures.  

Months of progress; a timeline of repair efforts completed since March 2020

What comes next for repair?

Repair of the West Seattle High-Rise Bridge is happening in two parts. The first part began early this year, through our stabilization efforts, which are expected to conclude at the end of this year. The second portion of the repair work is currently being designed by WSP, with implementation beginning in spring 2021.

Completing the final design for the West Seattle High-Rise Bridge repairs could not have happened before the current Phase I stabilization work is complete and we observe a winter thermal cycle.  SDOT and WSP need to understand how the High-Rise Bridge would respond to measures like additional post-tensioning strands, carbon-fiber wrapping, and releasing a jammed lateral bearing, and to see how cold weather impacts the bridge with newly-installed stabilization measures in place.

This type of bridge repair is an approach used around the world and both SDOT and a group of outside experts comprising our Technical Advisory Panel agree that repairing the bridge is feasible. To date, the bridge is responding positively to the stabilization work and in alignment with our modeling. These efforts have largely arrested crack growth.

Part II of the repair work will look similar to the work that’s already underway. It will include more post-tensioning work on other bridge spans, reviewing the seismic condition of the Pier 18 foundation, and completing a study that models how likely other parts of the bridge may be needing of future repairs before the bridge is eventually replaced.

We will continue to approach repair work methodically and carefully with ongoing monitoring and inspection. By the end of 2020, we expect to have a timeline for repair activities that provides more certainty on reopening and the funding needed for this pathway.

Repair durability and planning for future replacement

Though Mayor Durkan and SDOT are confident that repair is the right decision to most quickly reconnect this critical transportation link, this pathway remains a challenging engineering solution and we need to approach it carefully and diligently to manage the very real risks. SDOT will have a cost estimate and design for the bridge repairs in early 2021.

The success of the repair pathway depends on the West Seattle High-Rise Bridge’s reactions to stabilization measures and Phase II repairs. While we will do all we can to mitigate risk, there is the potential for another unplanned, future shutdown if the bridge does not perform as expected. Collectively, as a City, the repair pathway requires us to identify additional, ongoing bridge operations and maintenance resources, since a repaired High-Rise Bridge must be inspected and maintained into the future.

Above all else, however, repairing the bridge now requires a future long-term bridge closure for replacement, which will be challenging to fund and neatly sequence in a way that minimizes impacts.

Repairs will make it safe for traffic to resume using bridge once completed, and we anticipate successful repairs could allow continued use of bridge for many years to come. A more definitive understanding of how many years of service a repaired bridge is likely to provide will be developed through an assessment of how all bridge components are likely to age, to be completed later this winter in parallel with the repair design. Even then, however, that will only be an estimate based on our current understanding of the bridge and to inform the timing of eventual replacement. This will be work that continue to evolve and change as additional repair work is done and live load is restored.

We will take some action now to ensure we are prepared to replace the bridge when the time comes. That includes completing the first step of any bridge project, a study of various bridge types, sizes, and locations. We’ll also complete a traffic and revenue study as part of larger efforts to understand and develop a long-term funding and financing strategy for eventual replacement. 

No matter how long the High-Rise Bridge is closed, it still hurts. Reconnect West Seattle is the existing and growing framework focused on mitigating these impacts.

Reconnect West Seattle is an iterative, ongoing dialogue that envisions how we can achieve a reconnected West Seattle peninsula and healthier Duwamish Valley.

Street level view of East Marginal Way S with refreshed bike lane (including green driveway markings) on the right.
Back in September, on East Marginal Way S, we refreshed bike lane and driveway markings and replaced Tuff Posts along the bike lanes – both northbound and southbound. Photo Credit: SDOT,

We know this is not just another road closure or construction project. This is a human-centered emergency with profound impacts on equity, our families, on economic recovery. Though it’s the fastest path forward, repair still comes with a long-term emergency closure of the High-Rise Bridge that is disproportionately impacting communities of color in West Seattle and the Duwamish Valley as they absorb the vast majority of detour traffic in areas already facing higher levels of pollution, asthma, and environmental injustices.

Through our Reconnect West Seattle framework, we’re working closely with the community to support levels of travel that are similar to what they were before the High-Rise Bridge closure, while reducing environmental injustices that impact Duwamish Valley communities. The Reconnect West Seattle Implementation Plan, which we completed back in September, describes initial planned investments for neighborhood mitigation projects, bike projects, freight projects, and projects/services to support mobility.

Our Reconnect West Seattle framework has already implemented many traffic improvements, with lots more slated for 2021, but any efforts on the bridge come with double focus and effort on the ground to keep our communities safe. There are 55 projects 2020-2021 in the RWS Implementation Plan. We have completed 15 projects already and are planning to implement about 40 more projects by end of 2021.

As we work to repair the bridge, we will also continue to focus on the communities impacted by the closure – no matter how long. This starts with enabling increased transit ridership, more bicycle and pedestrian trips, and greater safety on our streets and sidewalks, especially in neighborhoods impacted most by detour route traffic.