DOT: End is in sight for Seattle's aging Alaskan Way Viaduct
SEATTLE - The end is in sight for the aging Alaskan Way Viaduct on Seattle's waterfront.
The state Department of Transportation this week laid out a comprehensive plan and timeline for tearing down the structure when a new two-mile Highway 99 tunnel opens beneath downtown Seattle.
Experts say the viaduct, built in the 1950s, is beyond its useful lifespan and is vulnerable to failure or collapse during an earthquake.
The DOT's plans envision opening the new Bertha-built highway tunnel in early 2019 and demolishing the viaduct soon afterward. The Battery Street tunnel would be decommissioned and filled with dirt starting in spring or summer 2019.
Connections to the new Highway 99 route would be opened in stages during 2019 and 2020.
Watch a video presentation of the plans ...
The public now is being invited to provide feedback on those plans online at a DOT website that spells out the whole complex process.
In addition, an open house will be held Thursday night from 5 to 8 p.m. at 1400 Western Ave., Seattle.
According to the DOT:
- Bids will be solicited for demolishing the viaduct and decommissioning the Battery Street tunnel later this year, and a contract will be awarded by early next year.
- The winning bidder will be expected to submit a plan for demolishing the viaduct by summer 2018 and public input on the plan would be sought in fall 2018.
- Alaskan Way would be shifted west out from under the viaduct in fall 2018.
- The viaduct would close for about a month in late 2018 or early 2019 to build Highway 99 connections to the new tunnel.
- The new tunnel would open to traffic in early 2019. By fall 2019, viaduct demolition would be complete.
- In mid-2020, new connections to Aurora Avenue North would be complete.
- The north entrance of the new tunnel will be three blocks north of the Battery Street tunnel's north entrance, which means streets that were previous cut off by Highway 99 can be reconnected.
The DOT says much of the work on the massive new tunnel project has already has been completed, including boring of the future tunnel, construction of a mile-long stretch of the new Highway 99 south of the future tunnel and construction of a new overpass south of downtown that allows traffic to bypass train blockages near the Port of Seattle.
Meanwhile, crews are getting the new tunnel itself ready for traffic by constructing roadway decks and installing mechanical, electrical systems and fire protection systems.