10/17 UPDATE: This weekend's northbound closure has been shortened. Northbound SR 99 will close Saturday, Oct. 20 at 6 a.m. and reopen Saturday afternoon by 5 p.m. The southbound closure remains unchanged.
This weekend, Oct. 19-22, brings the final scheduled inspection closure of the State Route 99/Alaskan Way Viaduct before the new SR 99 tunnel opens early next year. Both northbound and southbound SR 99 will be closed, including the Battery Street Tunnel.
- SR 99 closes southbound at 9 p.m. Friday, Oct. 19 and reopens by 5 a.m. Monday, Oct. 22. The closure is from the north end of the Battery Street Tunnel to South Spokane Street.
- SR 99 northbound closes at 6 a.m. Saturday, Oct. 20 and reopens by 5 p.m. the same day. This closure is from the north end of the Battery Street Tunnel to South Spokane Street.
- In addition to a final scheduled inspection, crews will be pouring concrete for the future highway at the SR 99 tunnel’s south portal.
Since 2001 WSDOT bridge inspectors have been closing the viaduct twice a year to inspect the structure. The 2001 Nisqually earthquake damaged the viaduct, prompting repairs and strengthening, and instigating a rigorous inspection program to make sure the structure remains safe for driving. This weekend will be the 33rd inspection since 2001.
The viaduct is scheduled to permanently close on Jan. 11th 2019, marking the start of three weeks of intensive roadwork to #realign99 into the new tunnel. WSDOT urges all drivers to make a plan for their commute during the closure, as it will be the longest major highway closure ever in the Seattle area.