The State Route 99 tunnel in Seattle will be closed for inspections on the first two weekends of October, as announced by the Washington State Department of Transportation (WSDOT). This marks the first extensive inspection since the tunnel was opened to traffic in February 2019. During this period, both northbound and southbound lanes will be closed, prompting WSDOT to advise drivers to seek alternative routes. The inspections aim to assess the structural integrity and safety of the tunnel, which is vital for its ongoing operation. WSDOT has highlighted the significance of these regular evaluations in maintaining the infrastructure and ensuring public safety.

The agency is committed to transparency and will provide updates as necessary during the closure period. The first weekend closure will begin on October 5, while the second will follow on October 12. Motorists are encouraged to plan ahead and allow extra time for their travels.