Tunneling machine arriving for big Seattle dig
SEATTLE (AP) — The world's widest tunnel boring machine arrives in Seattle in pieces Tuesday aboard a ship from Japan.
The $80 million machine called Bertha was built at a factory in Osaka. It will be reassembled in a pit to begin the year-long dig to create a two-mile tunnel under downtown Seattle.
The new section of Highway 99 replacing the Alaskan Way Viaduct will have a diameter of nearly 58 feet.