Alaskan Way Viaduct Replacement Program News

Washington State Department of Transportation


SR 99/Aurora Avenue North closures near South Lake Union, Aug. 21 – 24

Crews will close State Route 99/Aurora Avenue North near South Lake Union over the weekend of August 21 – 24. Travelers should plan ahead and prepare for additional local street congestion during the weekend.

The closure will result in a noticeable shift in traffic patterns on SR 99. Crews will move both directions of SR 99 near Harrison Street onto a new, curved structure west of the existing highway. This new structure is actually a bridge which will pass over roads leading from the future SR 99 tunnel.

Visit the program website for a diagram of this traffic shift, and visit WSDOT’s YouTube channel for a video explaining the shift and how it fits into the larger project.

SR 99 Closure Details – SR 99/Aurora Avenue North closed between the south end of the Battery Street Tunnel and Valley Street


Southbound lanes
  • Closed from 10 p.m. Friday, Aug. 21 to 5 a.m. Monday, Aug. 24
Northbound lanes
  • Closed Friday, Aug. 21 starting two hours after the end of the Mariners game. Will reopen by 5 a.m. Monday, Aug. 24
Aurora Bridge
  • WSDOT crews will also close up to two lanes of northbound SR 99 across the Aurora Bridge for bridge maintenance work between 5 a.m. and 5 p.m. Saturday, Aug. 22
Harrison Street at SR 99 – changes beginning Monday, August 24
  • Drivers will no longer be able to enter northbound SR 99 via westbound Harrison Street due to necessary work. Access to northbound SR 99 from Thomas and John streets will remain open.
  • Northbound drivers on SR 99 will be able to exit at Harrison Street as they do today.