SEATTLE -- The world’s largest tunneling machine is about to start burrowing under downtown Seattle.
The machine the state Transportation Department calls Bertha should begin by the end of the month and spend the next 14 months carving out a new route for Highway 99.
The $80 million machine is part of the $3.1 billion project to replace the 60-year-old Alaskan Way Viaduct, the double deck highway along the downtown waterfront.
Bertha was built in Japan and arrived by ship in April in 41 pieces. It has been reassembled in a pit near the CenturyLink Field and Safeco Field stadiums.
The Transportation Department and the contractor, Seattle Tunnel Partners, are holding a dedication ceremony on Saturday July 20 to give the public on last look before Bertha digs in.