SW Admiral Way Bridge Seismic Retrofit

Updated May 14, 2024

Project overview

Earthquakes could have a major impact on Seattle’s infrastructure. To address seismic risks to city infrastructure, the City of Seattle established a bridge seismic program to assess how vulnerable the City’s bridges were to earthquakes, and to retrofit bridges to better withstand the potential impacts of an earthquake.  ion joints, which help the bridge expand and contract during seasonal temperature changes.   

As part of the Levy to Move Seattle, 16 bridges were selected for seismic retrofits, including the Admiral Way North and South Bridges. The Admiral Way North and South Bridges are older bridges built prior to modernizing the seismic design code.

The bridges are on SW Admiral Way between 39th Ave SW and Walnut Ave SW, above Fairmont Ave SW. While it seems like one bridge when you’re traveling on it, the Admiral Way North and South Bridges are two bridges, side-by-side. Both bridges will be retrofitted, making them stronger and safer in the event of an earthquake. 

We’re not planning on changing the current use and operation of the bridge. The planned seismic retrofits to the Admiral Way North and South Bridges include several modifications to strengthen existing bridge components and reduce the bridge’s vulnerability to earthquakes. The following are major construction elements: 

• Installing carbon fiber wrapping to strengthen the bridge's crossbeams, columns, and arches 
• Strengthening the existing arch with a concrete infill wall 
• Installing concrete blocks and supportive shells for the bridge's columns and crossbeams 
• Repairing cracks and damaged concrete 
• Replacing the expansion joints at both ends of the bridge   

What to expect during construction

Construction will begin as soon as spring 2024 and is anticipated to last approximately 7-8 months. Once construction begins, we will continue to share information on our webpage and through regular email updates. You can sign up online to receive email updates.    
 
To complete the work as safely and efficiently as possible, the bridge will be closed to all people walking, biking, rolling, and driving for the duration of construction. We understand this closure will impact everyone who uses the bridge regularly and will do what we can to minimize impacts. We will share information about detours prior to the start of construction. 

We currently anticipate the following construction impacts:    

• Work in the public right-of-way near your home or business  
• Temporary on-street parking restrictions, with "no park" signs placed 72 hours in advance 
• A temporary bridge closure. We will notify nearby homes at least two weeks in advance and again 72 hours before the closure. 
• Staged construction equipment and materials as well as noise, dust, and vibrations in the work area 
• Typical weekday work hours of 7 AM – 5 PM, Monday through Friday   

Project Schedule 

_{* The schedule is subject to change.}

Once construction begins it is scheduled to last approximately 7-8 months. Construction schedules are also subject to change and depend on factors such as weather and availability of crews and materials.  

Funding

The project is funded through the Levy to Move Seattle. Approved by voters in 2015, the 9-year, $930 million Levy to Move Seattle provides funding to improve safety for all travelers, maintain our streets and bridges, and invest in reliable, affordable travel options for a growing city. In addition, this project has received federal funding. 

Get Involved

We're committed to keeping you informed and working with neighbors to limit construction impacts to the extent feasible. Here are some ways to get more information about the project:  

• Sign up for our project listserv to receive weekly project updates 
• Email the project team at BridgeSeismicRetrofit@seattle.gov  
• Leave a voicemail at (206) 775-8734. A project representative will return your call.   

Project Materials

We’ll update you with project materials such as mailings, flyers, and fact sheets as they are created throughout the construction phase of the project.