Times: Work nearly complete on assembling Highway 99 tunnel drill
SR 99 Tunnel Boring Machine Assembly
Credit: WSDOT
Workers stand in the shadow of what will become the world’s largest-diameter tunnel boring machine. Currently being assembled in Japan, the machine will dig the SR 99 tunnel beneath downtown Seattle starting in summer 2013. Scheduled to open to traffic in late 2015, the tunnel will replace the central waterfront section of the Alaskan Way Viaduct.