Alaskan Way procurement - TunnelCast
Video courtesy of WSDOT

October 2010: A giant TBM bored tunnel of 54ft (16.5m) diameter or more will replace the earthquake-damaged elevated SR-99 highway across the waterfront of Seattle, Washington.

Alaskan Way mega-project procurement - TunnelTalk, Oct 2010
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Taking mega TBMs to greater limits - TunnelTalk, June 2010


Alaskan Way bored tunnel alignment

Seattle, Washington, USA
Single bore segmentally lined TBM tunnel of 54ft (16.5m) diameter or more, passing 9,100ft (2.7km) under downtown Seattle at depths ranging from 60ft to 200ft (18-60m)
Double-deck highway tunnel
Washington State Department of Transportation
Project Value:
An estimated $1.69-2.1 billion
Project procurement:
Proposals for a design-build construction contract are due on Friday 28 October
Specified closed-face pressurized TBM of minimum 54ft (16.4m) diameter
Contract Award:
Scheduled for January 2011
Project opening:
Targeted for 31 Dec 2015