The giant Highway 99 tunnel-boring machine left Osaka harbor, Japan, at 1:40 a.m. Seattle time on Tuesday.
It should reach Terminal 46 in Seattle around April 1, the state Department of Transportation announced. Departure was delayed a few weeks to repair damage to its drive unit, at the assembly site.
The vessel Jumbo Fairpartner is one of the few ships on earth capable of bringing this load across the sea. The rotary cutting head, painted green, is fastened to the aft deck:
The cylindrical machine, the world’s largest at 57.5 feet in diameter, will depart from a pit in Sodo this summer, burrow beneath downtown, then emerge late next year at South Lake Union. The $2 billion, four-lane tunnel, the largest piece of the $3.1 billion viaduct replacement, is to open for traffic in early 2016.
The boring machine is nicknamed Bertha in honor of mayor of Seattle from 1926-28.
WashDOT has created a Bertha website and Twitter account to help the public monitor the voyage and arrival.