With the opening of Seattle’s SR-99 tunnel underway, the Alaskan Way Viaduct’s numbered days are coming to a close. The project gained notoriety when the tunneling machine, nicknamed Bertha, broke down and had to be repaired in the tunnel. With the viaduct decommission date approaching, Curbed Seattle answered some pressing commuter questions in a recent article.
According to the article, demolition of the viaduct will begin shortly after the new SR-99 tunnel opens on February 2 and 3. The first few weeks of opening will give WSDOT a chance to reroute the freeway through the tunnel, including moving the Battery Street Tunnel out of use to make connections from the new tunnel to Aurora Avenue North.
Demolition will start in sections near Seattle’s Pike Place Market, then move toward a sport close to the Seattle Aquarium.
Kiewit Infrastructure West Co. will demolish the viaduct. The company will begin demolition at the upper road deck first and work downward, with crews removing cross beams, then columns. Discarded concrete will also be moved to Terminal 25 where it will be used for the Battery Street Tunnel.
During demolition, some traffic will be directed through the tunnel, while others will move down a temporary surface street.
According to Curbed, the full scope of the project—including demolishing, reconnecting, and replacing roadways—is bid at $93.7 million. The project is expected to take up to two years to complete.
Source: Curbed Seattle