Building America's Longest Underground Highways

As land becomes more scarce and traffic gets progressively worse, Southern California's transit planners begin to look seriously at underground highways.

1 minute read

September 19, 2005, 9:00 AM PDT

By Chris Steins @planetizen


"But Los Angeles is in its 18th year as the nation's most congested metropolis, freeways have little or no space for new lanes and traffic experts are running out of time-shaving options.

So civic leaders are joining engineers to consider burrowing the longest highway tunnels in America.

...Three massive projects are under study in Southern California, each dwarfing any of the nation's 337 underground roadways, including the 2.6-mile tunnel in Boston's infamous "Big Dig," the most costly public works project in U.S. history.

...Southern California, with its mountainous terrain, underground aquifers and seismic vulnerabilities, may prove the ultimate testing ground for subterranean highways."

Monday, October 3, 2005 in The Los Angeles Times

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I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching. Mary G., Urban Planner

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching.

Mary G., Urban Planner

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