While we have known the Alaskan Way Viaduct’s days have been numbered for quite some time, the exact timeline has been constantly in flux amid years-long tunneling delays and uncertain testing schedules. Now, the elevated stretch of State Route 99 has a date for its final closure, at least for now: January 11, 2019. At that point, crews will start rerouting 99 to the new tunnel set to replace it.
Last we heard, the Viaduct was scheduled to shut down this fall, the Washington State Department of Transportation (WSDOT) says the date was moved to avoid holiday rushes and weather issues, and to provide advance notice.
After the Viaduct closes down, it will take approximately three weeks to make the necessary connections from SR 99 to the tunnel—during which that whole stretch of the highway will close to traffic. According to WSDOT, it will be the longest major highway closure in Puget Sound history, and the effects could last up to six weeks; the southbound ramp to Atlantic will close a week earlier, and the northbound ramp to Dearborn won’t open until two weeks after the switch is finished.
Once the tunnel opens, the Viaduct will be demolished. Contractor Kiewit Infrastructure West Co. has been officially selected to complete the work. Kiewit bid the project at $93.7 million, which includes demolishing the Viaduct and the Battery Street Tunnel; reconnecting Harrison, Thomas, and John to the new tunnel; and replacing the Marion Street Pedestrian Bridge.
When all the connections are complete, the two-mile, tolled tunnel will carry cars from around the stadium district to Aurora Avenue North near Seattle Center. The current estimated cost of the project is $3.2 billion. Who’s on the hook for $149 million in cost overruns depends on the outcome of a couple of lawsuits.
The tunnel was initially projected to open in December 2015, but after a two-year delay halted the drill from completing work until April 2017, the projected opening date was moved to early 2019.