OSAKA, JAPAN — Leaders from the Washington State Department of Transportation (WSDOT) and its contractor, Seattle Tunnel Partners, spent Thursday, Dec. 20, at the Sakai Works factory in Osaka, Japan, watching major components of the $80 million machine rotate, extend, retract, and move. Seattle Tunnel Partners will authorize shipment of the machine, dubbed Bertha, after testing is completed next month. Crews will then prepare the machine for its eventual departure to Seattle.
“This machine is incredibly innovative,” said Linea Laird, WSDOT’s administrator for the Alaskan Way Viaduct Replacement Program. “Using technology like this allows us to create a new highway 99 while keeping the viaduct open to traffic.”
Crews in Japan will spend the early part of next year disassembling Bertha into 41 separate pieces — the largest weighing up to 900 tons — and loading them onto a single ship. After a month-long trip across the Pacific Ocean, Bertha will land at the Port of Seattle’s Terminal 46, to the west of CenturyLink Field. Crews in Seattle will transport the pieces a few hundred yards east to an 80-foot-deep pit where the machine will be reassembled and launched beneath downtown next summer.
“Every last component was designed and built specifically for the soils beneath Seattle and the needs of this project,” said Chris Dixon, Seattle Tunnel Partners project manager, who like Laird attended Thursday’s ceremony. “It’s truly one of a kind.”
Hitachi Zosen Corporation was selected ahead of three other firms to manufacture the machine based on overall technical requirements, support capabilities, price, and schedule. Based in Osaka, Japan, the firm has successfully built more than 1,300 tunnel boring machines, a number of them for large-diameter tunnel projects. They supplied the tunnel boring machines for Sound Transit’s Capitol Hill Station to Pine Street segment and the Bay Tunnel near San Francisco, Calif.
Bertha’s size and complexity limited the number of firms that were qualified to manufacture her, Laird said.
“She was built in Japan, but the tunnel project has brought plenty of jobs to Washington,” Laird said. “All you have to do is drive by the construction zone to see how many people this project has put to work in Seattle.”