Local Information

Seattle drivers take note: SR 99 - Alaskan Way Viaduct closes for a scheduled inspection, Oct. 6-9

Monday, October 2, 2017 - 11:23

Northbound SR 99 closure starts earlier and lasts longer than usual for tunnel-related work

Laura Newborn, Alaskan Way Viaduct Replacement Program communications,
206-805-2871; 206-639-8577 (mobile)
SEATTLE – The Alaskan Way Viaduct through Seattle closes this weekend, Oct. 6 – 9, for a twice-yearly inspection designed to keep the aging roadway safe for everyday use.
Both directions of State Route 99 will close between South Spokane Street and the north end of the Battery Street tunnel, but the timing of this semiannual closure is different from past inspections.
The northbound roadway closes at 11 p.m. Friday, Oct. 6 and reopens at 5 a.m. Monday, Oct. 9. This will allow the SR 99 tunnel contractor Seattle Tunnel Partners to complete tunnel-related work.  The southbound roadway closes from 5 a.m. to 6 p.m. on Saturday, Oct. 7 and Sunday Oct. 8.
Engineers from the Washington State Department of Transportation closely inspect the elevated portion of SR 99 every October and March. The viaduct was strengthened and reinforced (pdf 3 mb) after the 2001 Nisqually earthquake and will be replaced by a 2-mile-long tunnel, scheduled to open by early 2019.
Closure Details

  • The SR99/Alaskan Way Viaduct will be closed between South Spokane Street and the north end of the Battery Street Tunnel
  • Northbound SR 99 closes from 11 p.m. Friday, Oct. 6 through 5 a.m. Monday, Oct. 9
  • Southbound SR 99 closes from 5 a.m. to 6 p.m. Saturday, Oct. 7 and Sunday, Oct. 8

Tunnel Progress
Seattle Tunnel Partners is currently building the tunnel’s double-deck highway, installing and testing systems in the tunnel. 

The tunneling machine Bertha completed the outer walls of the tunnel in April 2017. The dismantling and removal of Bertha concluded in August 2017.

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