Information from the Seattle Department of Transportation

We’ll be one step closer to reopening a stronger, safer West Seattle Bridge on September 18 when we meet a major milestone this weekend: completing all final phase carbon-fiber wrapping! We initially applied epoxy crack injections and carbon fiber wrapping before post-tensioning the bridge. This latest round of epoxy and carbon-fiber wrapping is our final round after we successfully tensioned the bridge. Epoxy and carbon-fiber wrapping work in tandem to first seal cracks and then apply a strengthening layer of protection that helps prevent cracks from forming in the future.

This weekend, we’re removing one of the two work platforms we needed for the carbon-fiber work. We’ll begin lowering the west work platform on Saturday. After we remove the west platform, we’ll immediately begin disassembling it. We expect to lower the east platform later this month.

This week we also finished sealing the post-tensioning system. We injected a grout compound into the post-tensioning ducts that contain the tightened cables. By filling the ducts with grout, we protect the steel cables from air and moisture to prevent them from rusting.

While we complete the West Seattle Bridge repairs, we made more progress on maintenance work and other activities needed to reopen the bridge. This work including concrete pours on the bridge deck, continued rewiring work for the bridge lighting, expansion joint plate installation, and overhead roadway sign installation.

West Seattle Bridge Final Repairs Checklist

• Completed: Let the post-tensioning concrete set and cure
• Completed: Install post-tensioning ducts
• Completed: Pre-tensioning epoxy injections and carbon-fiber wrapping
• Completed: Install post-tensioning strands
• Completed: Tension post-tensioning strands
• Completed: Complete final epoxy injections and carbon-fiber wrapping
• Completed: Complete cure time for the carbon-fiber wrapping
• To do: Remove work platforms
• To do: Load test and inspect the repairs
• To do: Restore the bridge deck
• To do: Demobilize the site

Construction in West Seattle and South Park this weekend

As part of our Reconnect West Seattle program and ongoing street maintenance, we will be completing several projects this Saturday. Work is expected to begin as early as 6 AM and conclude by 5 PM. Please expect delays, drive safely in work zones, and follow directions from signs and flaggers.

• We’re paving 8th Ave S from S Kenyon St to S Portland St in South Park. We will restrict parking and maintain one driving lane of traffic in each direction.
• We’ll be working in south Delridge at 16th Ave SW and SW Cambridge Stto update curb bulbs and curb ramps. We’ll maintain one driving lane of traffic in each direction.
• We’ll be replacing concrete panels as part of necessary maintenance work on 16th Ave SW and SW Myrtle St. We’ll maintain one lane of traffic in each direction.
• To improve visibility due to overgrown landscaping, we’ll be on SW Roxbury St at Olson Place SW to clean the median islands located at the intersection. We will close a driving lane in both directions on either side of the median, so people driving can expect delays.

On Saturday and Sunday, our traffic signal crews will be replacing overhead signs and complete signal wiring activities on 14th Ave S and S Cloverdale St. The work is anticipated to begin as early as 7 AM and conclude by 3 PM. During this work, we’ll need to turn off the signal for a period of time. We’ll have a uniformed police officer directing traffic at the intersection to make sure traffic is moving efficiently. Please navigate the area with caution. A detour will be set up for people using the sidewalk.

On Sunday, to help keep West Seattle Bridge traffic moving efficiently, we will be paving a median island on West Marginal Way SW, just north of the Highland Park Way SW intersection. Work is anticipated to begin as early as 7 AM and will conclude by 3 PM. Please anticipate delays while driving through the area.

Question of the week: How is SDOT ensuring safety of the West Seattle Bridge repairs?

Safety is our #1 priority. To ensure the safety of the bridge repairs, we will complete comprehensive testing before reopening the West Seattle Bridge. We have a robust monitoring system in place with instruments that provide real-time details 24/7 and alerts to staff overseeing the performance of the bridge.

Bridge repairs included three key procedures: epoxy injections to fill cracks, carbon-fiber wrapping to add strength, and post-tensioning with steel cables to compress the concrete. Together, these methods rehabilitated the entire structure and will keep the bridge safe for decades to come. To learn more about the bridge repairs, watch our full collection of repair videos on the SDOT YouTubepage.