SEATTLE — Seattle's busiest bridge is on track to open in mid-September, two-and-a-half years after it closed for emergency repairs, the Seattle Department of Transportation announced Thursday. SDOT plans to reopen the bridge to regular traffic on Sunday, Sept. 18, restoring a key route across the Duwamish River and ending detour routes.

"It is a relief to be so close to the end of this difficult closure," said Seattle Mayor Bruce Harrell. "We recognize how painful this closure has been for so many people, businesses, and communities. 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 city closed the 40-year-old bridge span in March 2020 after routine inspections found cracks rapidly growing along the concrete structure. Crews began emergency repairs that year to shore up the bridge and prevent more damage and began work last year on a permanent fix. The city initially targeted a summer reopening, but a prolonged concrete labor dispute pushed the timeline into September.

"This monumental effort has repaired the cracks and made the bridge stronger and safer," said Heather Marx, SDOT's West Seattle Bridge Program Director. "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 project."

The extensive list of repairs includes a new "post-tensioning system" inside the bridge, which required contractors to install dozens of miles of steel cables to bolster the "backbone" of the structure. Crews also wrapped carbon fiber sheets inside and outside the bridge and filled the cracks with epoxy.

The project also features a new monitoring system comprised of hundreds of sensors and cameras designed to detect subtle movements in the structure and any growth in cracks, providing inspectors real-time information around the clock.

SDOT said meeting the Sept. 18 target will depend on completing a few remaining tasks, including:

Officials said work went smoothly through the summer, but the final stretch involves complex work that could present unforeseen challenges. Drivers can track any changes and learn more about the comprehensive repair project on SDOT's blog.

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