Highway 99 Tunnel
The contractors building a tunnel under Seattle have invited the media to a special viewing of Bertha, the world’s largest tunnel boring machine, as they prepare to pull it out of a pit for repairs.
A new highway tunnel through downtown Seattle won’t be open until August 2017, about 20 months behind schedule, state transportation officials said Monday.
Washington state archaeologists who took a look at shell deposits found by crews digging a 120-foot-deep pit that will provide access to a stalled Seattle tunneling machine have given the all-clear signal for work to proceed.
Bertha, the machine boring the State Route 99 tunnel in Seattle, will not resume digging until the end of March 2015 and that the tunnel will not open until November 2016, according to the Washington State Department of Transportation.
It seems that everything connected with the effort to dig a highway tunnel under downtown Seattle is big — from the tunneling machine that stopped working last December, to a large plywood wall planned to shield neighbors from the noise of repairing the machine.