The Seattle Department of Transportation (SDOT) is nearing a major milestone in the SW Barton Street Layover Repaving Project, a critical infrastructure effort to permanently repair a failing stretch of roadway plagued by unstable soil and heavy bus traffic.

The project, which began in April 2026, involves a full-depth reconstruction of SW Barton St between 29th Ave SW and 26th Ave SW. For years, the area has suffered from severe cracking and sinking because it sits atop a peat bog. To address this, crews have excavated the sinking soil and are replacing it with lightweight cellular concrete (LCC)—a specialized material filled with tiny air bubbles that reduce density while maintaining the strength necessary to support heavy transit vehicles.

Current Progress and "Curing Break"

As of the week of June 30, crews are close to finishing the primary concrete work. Workers are scheduled to pour the north-side curb island tomorrow, and coordination is currently underway with Seattle City Light to reenergize streetlights in the area.

Following this push, residents will notice a temporary pause in activity. Construction will be suspended from July 2 until July 20 to allow the new high-strength concrete to cure entirely. SDOT officials noted that traffic cones and safety devices will remain in place during this period to keep the roadway clear. Work is expected to resume on July 20, focusing on striping removal and repainting.

Transit and Traffic Impacts

The reconstruction is vital for King County Metro, as the SW Barton layover serves as a critical staging area for the RapidRide C-Line and Route 21. These zones allow drivers to take required breaks and reset schedules to ensure downtown transit reliability.

While construction continues, the following impacts remain in effect:

• Traffic: Only the north half of SW Barton St is open; drivers should expect continued delays.
• Transit: RapidRide C-Line and Route 21 remain detoured to SW Trenton St, with temporary stops in place.
• Pedestrians: The south-side sidewalk is closed, though Roxhill Park remains accessible via SW Roxbury St or 29th Ave SW.

Looking Ahead

Once completed in Fall 2026, the project aims to provide a smoother, quieter ride for all commuters and more reliable operations for King County Metro. By replacing failing asphalt with a stable, long-term concrete surface, SDOT expects to significantly reduce future maintenance costs and improve safety near Westwood Village.

Residents with questions or concerns are encouraged to contact the project team at SWBartonLayover@seattle.gov or by calling (206) 400-7570