Southbound I-5 mainline to close in downtown Seattle overnight July 11

Southbound Interstate 5 will close overnight on July 11 for maintenance, with all traffic rerouted through express lanes until 6 a. m. on July 12. The closure will affect lanes near the Seattle Convention Center, requiring all vehicles to exit at Stewart Street. Key ramp closures include the eastbound Mercer Street on-ramp and the Yale Avenue/Howell Street on-ramp, as well as the Union and James Street off-ramps.

The Washington State Department of Transportation (WSDOT) will conduct fire system testing under the Convention Center during this time. Travelers should anticipate delays and consider alternate routes to avoid congestion. WSDOT encourages the use of their traffic app for real-time updates. This maintenance work highlights ongoing efforts to ensure safety and functionality on key infrastructure. The express lanes will remain operational for southbound traffic, with northbound lanes closing early to facilitate the maintenance.