A curving, 4-mile-long tunnel is proposed to run 610 feet beneath Washington state's Puget Sound with a 6% grade. The tunnel, the brainchild of University of Washington instructor and retired civil engineer Bob Ortblad, would link Mukilteo and Clinton and would provide an alternative to the ferry system.
Proposed tunnel would extend well below Puget Sound
Sign up for AGC SmartBrief
News and information for general contractors
Get the intelligence you need: news and information that is changing your industry today, hand-curated by our professional editors from thousands of sources and delivered straight to your inbox.