10:30am

Sun October 14, 2012
Colorado Wonders

Happy 20th Anniversary To I-70's 'Modern Engineering Marvel'

Sunday marks the 20th anniversary of I-70 through Colorado’s Glenwood Canyon. That stretch of interstate often referred to as a “modern engineering marvel” took 13 years and nearly $500 million to construct.

According to the Colorado Department of Transportation, state-of-the-art techniques were used for rock excavation, traffic handling and re-vegetation. Engineers ultimately constructed two roadways, one elevated, greatly reducing the impacts, both environmental and aesthetic.

Construction of the Glenwood Canyon project involved:

  • 300 engineers and other project crewmembers
  • 40 bridges
  • 15 miles of retaining walls
  • (2) 4,000-foot-long tunnels
  • 150,000 new trees and shrubs
  • 30,000 tons of structural and reinforcing steel
  • 810,000 tons of concrete

Exiting Hanging Lake Tunnel, heading west on I-70
Credit Carl Berger / Flickr - Creative Commons

History of I-70

The Federal Highway Act of 1944 authorized Interstate 70 between Denver and the Kansas state line and there was no interstate mileage allotted west from Denver. This omission was later addressed under the 1956 Interstate Act. Initially, Colorado was not be able to build I-70 west of Denver because Utah was not interested in a connecting interstate route through eastern Utah.

But, officials with the Colorado Department of Highways negotiated with Utah officials and were able to agree on a route. Congress approved the additional mileage of I-70 from Denver west to U.S. 91, to become I-15, in south-central Utah in October, 1956.

If you've never traveled on I-70 through Glenwood Canyon, you're missing out on an experience. Here's an excellent guided video with annotations from YouTube user InterstateKyle heading east towards Eagle and Vail.

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