I-70 through the Glenwood Canyon, which required double-decking the existing two-lane highway, included over 40 bridges and viaducts, and five tunnels. The widening of this route has significantly improved safety, provides access to the river and tourist destinations, and has become a major thoroughfare for freight transportation across Colorado.
Project Type:Widening Project Mode:Highway Average Annual Daily Traffic:17,000 Length (mi):12.50
Economic Distress:1.41 Population Density (ppl/sq mi):17 Population Growth Rate (%):2.49
Employment Growth Rate (%):4.53 Market Size:14,621 Airport Travel Distance:56.15 Topography:17
Region:Rocky Mountain / Far West State:CO County:Garfield
City:Glenwood Springs Urban/Class Level:Rural Local Area:Glenwood Springs
Impact Area:County Transportation System:Highway GIS Lat/Long:39.557679 / -107.243950
Initial Study Date:1987 Post Constr. Study Date:1997
Constr. Start Date:1987 Constr. End Date:1992
Project Year of Expenditure (YOE): 1992 Planned Cost (YOE $):N/A
Actual Cost (YOE $):490,000,000 Actual Cost (curr $):873,365,953
NOTE: All pre/post dollar values are in 2013$
Select a region to display the conditions for that region:
NOTE: All impact dollar values are in 2013$
|Income (in $M's)||128.78||90.15||218.93|
|Output (in $M's)||408.42||285.89||694.31|
The completion of the last section of I-70 through the Glenwood Canyon in Colorado required double-decking the existing two-lane highway The highway spans a 12.5 mile long scenic gorge on the Colorado River. The project, which took 12 years to complete, consists of a series of over 40 bridges and viaducts, and five tunnels. The widening of this route has significantly improved safety, provides access to the river and tourist destinations, and has become a major thoroughfare for freight transportation across Colorado. The highway was completed on October 14, 1992 with a cost of $490 million ($737 million in 2007 dollars). It was one of the most environmentally sensitive, challenging, and expensive (per road mile) projects in the federal highway network. The net increase in jobs attributable to the highway is estimated at 2,400.
2.1 Location & Transportation Connections
I-70 in Glenwood Canyon is located in Western Colorado in Garfield 5 miles east of Glenwood Springs, 150 miles east of Grand Junction and 100 miles west of Denver. Highway 82 connects Glenwood Springs with Aspen, 40 miles southeast. Scheduled air service is available at Eagle airport, 35 miles away. Glenwood Springs is on the major rail route through western Colorado. Railroad lines owned by Union Pacific pass through Glenwood Springs and run along the south side of the Colorado River in Glenwood Canyon.
2.2 Community Character & Project Context
Glenwood Canyon is a rugged, scenic 12.5 mile long gorge on the Colorado River in western Colorado in the United States. Its canyon walls climb as high as 1,300 feet above the Colorado River. It is the largest such canyon on the Upper Colorado. Glenwood Springs is the closest town to the Canyon. The industries that drive the economy in Glenwood Springs are natural gas and oil shale extraction, construction of workforce housing (for ski resorts), services, and outdoor recreation. Many residents work in either Vail or Aspen.
The population of Glenwood Springsincreased by approximately 1,000 people from 1990 to 2000 and unemployment has stayed between 2% and 3% from 2000 to 2007. Garfield County increased its population from 26,975 in 1987 to 39,210 in 1997 and also had an unemployment rate between 2% and 3% from 2000 to 2008.
The highway through Glenwood Canyon was the final section of I-70 to be constructed. It replaced a dangerous, two-lane highway built in 1938. The project completed the original U.S. interstate highway system. With funding approved, the original plan was to blast into the canyon side to create a 4-lane highway. However, environmentalists lobbied to protect the natural surroundings and ultimately a new construction technique was used to deck the east and west bound lanes, minimizing disturbance to the canyon. This technique was called balanced cantilever construction and consists of pre-fabricating a section of the bridge and lowering it in from above instead of building it up from below. After the bridge column is built and put into place, a gantry crane is positioned atop the column and is used to fill in the gap between bridge sections outward from the column also using pre-cast segments.
Despite special efforts to minimize ecological impacts, several environmental groups actively sought to stop construction. The Supplemental Environmental Impact Statement (EIS) conduced in 1983-84 was challenged in local courts in 1984 when the Colorado Open Space Council and the Sierra Club sought a restraining order to stop construction, resulting in a temporary injunction. The case was brought to federal courts and was settled when federal judge rejected the plaintiff's arguments but required contractors to disturb as little of the canyon as possible. The project included construction of over 40 bridges and viaducts, five tunnel bores and 15 miles of retaining wall, for a total of 12 miles of roadway. The highway was completed in October 1992 at a cost of $737 million (2007 dollars). The federal government funded over 92% of the project.
One of the tunnels houses facilities for traffic management, maintenance, and emergency response services. The corridor also has four full-service rest areas, a bicycle path running the canyon's entire length, and special facilities for launching rafts, boats, and kayaks.
I-70 in Glenwood Canyon is a model of environmental preservation, safety, and mobility, aided by local citizen involvement and good planning. The community became involved during the early stages of planning and design in the 1970s, and encouraged CDOT to include recreational facilities in the project's overall design. Local residents now state that the canyon is safer, cleaner, and more accessible than before the highway was upgraded to an interstate. Several other government organizations were involved with the project, including the Army Corps of Engineers, the Colorado Division of Wildlife, the Bureau of Land Management, and the Forest Service. The project won more than 30 awards, including the 1993 Outstanding Civil Engineering Achievement Award from the American Society of Civil Engineers.
4.1 Transportation Impacts
Congestion along Highway 6 (the precursor to I-70) increased significantly between 1970 and 1979, when traffic volume nearly doubled from an average of 3,301 vehicles per day to 6,026 vehicles per day. By the time the project was completed in 1992, average daily traffic had increased to 10,762. Average daily traffic is now approaching 17,000 vehicles per day.
Since the upgrade to an interstate, the annual number of crashes in Glenwood Canyon has dropped nearly 40 percent, despite increases in traffic volume. From 1975 to 1980, the average number of annual crashes was 106. That has since decreased to 67 crashes annually during the 1997-2001 time period.
4.2 Demographic, Economic & Land Use Impacts
In the 1970's, Garfield County was a center of oil and natural gas extraction. On May 1982, Exxon announced it was dropping its $5 billion Colony oil shale project near Parachute in Garfield County and laid off 2,200 workers. Many of these workers got jobs on the highway construction in Glenwood Canyon, helping to reduce the economic impact from Exxon's departure.
Since the majority of the traffic that uses I-70 in Glenwood Canyon is pass-through, most of the economic impacts associated with the highway project are realized by the ski resorts (such as Vail and Aspen/Snowmass) to which it provides access, or by freight carriers that transport shipments through the region. The highway also has provided easier access to support a growing tourism and outdoor recreation industry in Glenwood Springs.
A significant amount of growth in Glenwood Springs and Garfield County can be attributed to I-70, which has been the only large highway access project in the area for decades. With several access points to the river now more easily reachable, fishing, rafting, and other recreational uses has grown considerably. The highway as led to estimated employment growth of 2,400 jobs.
Glenwood Springs has several attractions, such as vapor caves, hot springs, an adventure park, and winter sport activities that has attracted tourists year round for decades. Glenwood Springs is also an affordable bedroom community for employees that work in Vail or Aspen. Property values have more than doubled between 1990 and 2000 as additional employees have moved into the area. Natural gas extraction has returned to Garfield County, and in 2007 supported over 2,400 jobs (11% of the County's total employment.) There are currently 29 active rigs in the area and 65% of Garfield County's revenues come from an ad valorum tax on natural gas extraction. As the industry responds to fluctuations in energy prices, it will affect the economic well-being of the area.
City of Eagle
VP Tourism Marketing
Case Study Developed by Economic Development Research Group, Inc.