SEATTLE — After recently completing construction milestones, the Seattle Department of Transportation (SDOT) announced Thursday morning that the West Seattle Bridge is expected to reopen to traffic on Sept. 18.
The department said all traffic restrictions on the Spokane Street Swing Bridge, also known as the West Seattle low bridge, will also end on Sept. 18.
The planned reopening is dependent on crews completing the remaining work on the bridge, which includes finishing epoxy injections, carbon fiber wrapping, paving and safety inspection platform installation. The SDOT said crews will also conduct “robust safety testing” of the bridge before reopening it to traffic.
"We recognize how painful this closure has been for so many people, businesses, and communities,” said Seattle Mayor Bruce Harrell. “Their safety has been at the core of this repair effort since the beginning. As we reopen the bridge and reconnect our city, we are bringing our communities together with the confidence that the bridge is now stronger and safer for everyone."
The SDOT said crews installed “an intelligent monitoring system inside the bridge made up of hundreds of movement sensors, cameras, and other instruments.” The department said the system will monitor the bridge 24/7 to detect “subtle movements” or any growth of existing cracks in the bridge.
The West Seattle Bridge closed in March 2020 after inspectors found cracks rapidly growing in the structure. The bridge was 40 years old at the time of the closure. Crews finished emergency repairs in 2020 to keep the bridge standing and to prevent further cracking.
Last month, the SDOT announced crews completed a “major construction milestone” and finished tightening steel post-tensioning cables inside the bridge. The steel cables help reinforce and support the bridge, prevent it from cracking, and helps the bridge “respond to environmental factors such as weather, vehicle loads, and other external forces.”
“This monumental effort has repaired the cracks and made the bridge stronger and safer,” said Heather Marx, director of the West Seattle Bridge Safety Program. “SDOT is confident that the bridge will now stand strong for decades to come, fulfilling its original intended lifespan. We appreciate the community’s resilience as we navigated the uncertainties of this challenging project.”
The city said post-tensioning is one of the three “key repair procedures” to bring the bridge back into service. The other repair procedures include epoxy injections to fill cracks in the bridge and carbon-fiber wrapping to add strength to the structure.
The bridge is opening a few months later than the initial estimate. Officials said the delay was caused by a months-long concrete strike, which prevented the contractor working on the bridge from receiving concrete deliveries for two months.