**UPDATE** As of 3:55 p.m., Sunday, Oct. 19, all lanes of SR 99 are open from South Spokane Street to Valley Street.
State Route 99 will be closed through downtown Seattle this weekend for SR 99 tunnel construction and the semiannual inspection of the Alaskan Way Viaduct.
Starting Friday night, Oct. 17, crews will close a small section of SR 99 just north of the Battery Street Tunnel. This closure will give them the space they need to move underground utility lines. Additionally, the viaduct will close during the day on Saturday, Oct. 18, and Sunday, Oct. 19, to allow WSDOT bridge inspection teams to conduct a regularly scheduled inspection of the aging structure.
SR 99 closure details
10 p.m. Friday, Oct. 17 through 5 a.m. Monday, Oct. 20: SR 99 will be closed between the Battery Street Tunnel and Valley Street for utility and paving work.
6 a.m. to 6 p.m., Saturday, Oct. 18 and Sunday, Oct. 19: The SR 99 closure will be extended south to South Spokane Street to allow WSDOT bridge inspectors to conduct their semiannual inspection of the viaduct. Preliminary inspection results will be released once they are available.
8 a.m. to noon, Saturday, Oct. 18: The SR 99 closure will be extended north to North 39th Street in both directions for the 2014 Making Strides Against Breast Cancer walk.
Survey crews walk the viaduct during a previous inspection.
Other highway closures
SR 99 isn’t the only highway in town that will be affected by construction. Crews are taking advantage of an on-the-road weekend for Seattle’s sports teams to do other road work in the area. SR 520 will also be closed that weekend
Be sure to plan your trip in advance and be prepared for additional congestion. Drivers can get up-to-the minute information on closures and traffic on the web at WSDOT’s What’s Happening Now
page, on WSDOT’s mobile app
, on Twitter @wsdot_traffic
and by calling 5-1-1.