The Glenwood Canyon route of I-70 would be the final link of the interstate highway system running east and west through Colorado – part of an overall instate highway system proposed by President Dwight D. Eisenhower.
In the early '70s, the campaign for public support of the canyon route was in full swing. A pair of filmmakers produced a film for the chamber of commerce in support of the canyon route, and they screened their film far and wide, going as far as Washington, D.C., to show the film to the Federal Highway Administration and many other federal agencies.
Two other routes were considered as alternative possibilities: Cottonwood Pass and a route over the Flat Tops. But both were eventually rejected due to their higher elevations and costs.
The proposed project saw plenty of opposition from environmental groups and from those concerned about the design and cost of the Glenwood Canyon construction.
"The eruption of opposition that began in the 1960s intensified and persisted through the first half of the 1970s," wrote Conrad Schader in "Glenwood Canyon: From Origin to Interstate." "Protests ranged from fiery letters to newspaper editors to demonstrations within the canyon. There were lawsuits, hearings, additional surveys and the time-consuming involvement of scores of government agencies."
John Denver even joined the opposition camp, at one point attempting to prove a point about the canyon's narrowness by throwing a rock across the Colorado River in the canyon — though it apparently took him several tries.
"As of the end of 1975, over ($1 million) had been spent over a nine-year period in studies and design concepts for the stretch of interstate highway which might, or might not, be built through the canyon," wrote Jim Nelson in "Glenwood Springs: The History of a Rocky Mountain Resort."
The Federal Highway Administration recommended the canyon route in 1975, and the next year the U.S. Department of Transportation finalized the route. The Colorado Highway Commission approved construction of the interstate in 1977.
In 1980, "construction began on the interstate through Glenwood Canyon at No Name," wrote Nelson. "The project cost was estimated at close to $300 million. The plan was to begin the construction at both ends of the canyon, working toward the more difficult center sections. The construction of the canyon highway bolstered the economy of Glenwood Springs for the next 10 years or so." During construction on I-70 west of Glenwood Springs, crews stumbled upon dinosaur fossils, and the idea of turning the site into a state park was floated for a while.
Glenwood Canyon I-70 Final Link
Length: 12 miles
Cost: $490 million
Construction Began: 1980
Construction Completed: 1992
A road had existed through spectacular Glenwood Canyon , with its cliffs towering a maximum of 2,000 feet above the Colorado River , from pioneer times. Photos of teams and wagons negotiating a rough trail through the canyon date from the 1880s.
The Taylor State Road was completed between Denver and Grand Junction in 1902. It was the first improved vehicle road through Glenwood Canyon .
The final link of I-70 through Glenwood Canyon has been hailed as an engineering marvel because of the care taken to incorporate the interstate improvements into the fragile canyon environment while leaving as much of the flora and fauna intact as possible.
As many as 500 highway workers were employed in the canyon each day. The public driving through the area marveled at the new retaining walls, 40 viaducts and bridges, some of which were construction using unique and spectacular slip-form gantry imported from France . At traffic sometimes that sometimes approached 30 minutes or more, drivers had a chance to get out of their vehicles and watch first-hand at the construction activities going on around them.
Construction of three tunnels, 15 miles of retaining walls, and numerous other structures, comprised a challenging but very rewarding project. The Glenwood Canyon project required 30 million points of structural steel, 30 million pounds of reinforcing steel, and 400,000 cubic yards of concrete weighing 1.62 billion pounds.
The result of the Glenwood Canyon I-70 Final Link is much more than just a transportation facility. State-of-the-art rest areas at No Name, Grizzly Creek, Hanging Lake , and Bair Ranch provide opportunities for rest, education about the canyon and the project, and direct access to recreational pursuits such as river rafting and bicycling/jogging/walking along the canyon's recreation path.