Colorado's I-70 through Glenwood Canyon Remains an Engineering Marvel

October 11, 2012 - Northwestern Colorado/CDOT Region 3 - Original project team gathers for a 20-year reunion.

STATEWIDE – This Sunday, October 14, 2012, the stretch of interstate often referred to as a “modern engineering marvel” celebrates its 20th anniversary. I-70 through Colorado’s Glenwood Canyon took 13 years and nearly $500 million to construct—and still, the elevated highway that was delicately sculpted through the 12.5-mile Colorado River gorge remains a vital transportation corridor, a popular attraction and an important link to world-class recreation.

In the planning stages, a citizen’s advisory group greatly influenced the design of a project that would “tread lightly” in the canyon. 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. The project received the 1994 ASCE Outstanding Civil Engineering Achievement award, as well as more than 30 other awards and recognitions.

To celebrate 20 years, some 50 project engineers, consultants, designers and others gathered at the historic Hotel Colorado in Glenwood on September 7 for an evening of reminiscing and a day of cycling along the canyon bike path they constructed.

In all, the Glenwood Canyon project involved:  300 engineers and other project crewmembers, 40 bridges, 15 miles of retaining walls, two 4,000-foot-long tunnels (including one that houses a traffic management and emergency service facility), 150,000 new trees and shrubs planted, 30,000 tons of structural and reinforcing steel, 810,000 tons of concrete, four full-service rest areas and much more.

“Like me, many cut their engineering teeth on this project,” says (current) CDOT Program Engineer Joe Elsen, who at 22 had just begun with the department as a surveyor. “And for many of us, this remains the project of our careers.”

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