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Eisenhower Tunnel Official name Eisenhower/Johnson Memorial Tunnel [1] Carries 4 lanes of I-70 Crosses Continental Divide Locale Approx. 60 mi (97 km) west of Denver, Colorado Maintained by Colorado Department of Transportation
Design Twin-bore tunnel Total length 1.693 mi (2.72 km) westbound 1.697 mi (2.73 km) eastbound Width 40 ft (12.2 m) each AADT 32,260 vehicles (2007) Opening date 1973 (westbound) 1979 (eastbound) Toll None Coordinates 39°40'44?N 105°55'12?W? / ?39.67889°N 105.92°W? / 39.67889; -105.92 The Eisenhower Tunnel (sometimes called "The Ike") is a vehicular tunnel located on Interstate 70 approximately 60 mi (97 km) west of Denver, Colorado. The tunnel was built under the Continental Divide, and at a maximum elevation of 11,158 ft (3,401 m) above sea level, it is one of the highest vehicular tunnels in the world. It is also the longest mountain tunnel built under the Interstate highway program and one of the last major pieces of the system to be completed. Its full official name is the Eisenhower/Johnson Memorial Tunnel; the westbound bore is named after U.S. President Dwight D. Eisenhower (for whom the Interstate system is also named), the eastbound bore after Edwin C. Johnson, a former governor and U.S. Senator from Colorado who lobbied for an Interstate Highway to be built across Colorado.
Description
The tunnel is a two-bore tunnel with each bore approximately 1.7 mi (2.74 km) long. In 2002, over ten million vehicles passed through the tunnel, many of them driving between the Denver area and popular skiing locations west of the Continental Divide. The eastern end of the tunnel is under and surrounded by the Loveland ski area. Trucks that cannot safely pass through the tunnel (over 13' 6" (4.1 m) in height and/or carrying hazardous materials), and bicycles, pedestrians and those that wish to stop and view the scenery must take the longer and steeper climb and descent of the older U.S. Highway 6 across Loveland Pass, 834 ft (254 m) higher at 11,992 ft (3,655 m) above sea level. Other than the above exceptions, the tunnel has replaced the pass for general vehicular traffic. While less formidable than the older route, the approach to the tunnel on both sides is steep (up to 7% in places), and runaway truck ramps are available for truckers who lose control. The ascent and descent to the tunnel can also be dangerous in winter. During winter storms that require closing Loveland Pass, there is a procedure in place to allow Hazmat trucks to use the tunnel. Once per hour, one of the tunnel bores will be closed to regular traffic, and the trucks will be guided through the tunnel in a convoy with police escorts.
History
Eastern approach to the Eisenhower Tunnel The idea for a tunnel under Loveland Pass has existed, at least since the 1940s. Serious discussion began when the state of Colorado began lobbying for the Interstate Highway System to route a transcontinental interstate across Colorado, which was not originally included in the plans. After a round of negotiations with Utah officials, it was decided the best option was to follow the US 6 corridor. This would mean a way would have to be found to build across Loveland Pass that conformed to Interstate Highway standards. Construction on the first bore of the tunnel was started on March 15, 1968.[4] Construction efforts suffered many setbacks and the project went well over time and budget. One of the biggest setbacks was the discovery of fault lines in the path of the tunnel that were not discovered during the pilot bores. These faults began to slip during construction and emergency measures had to be taken to protect the tunnels and workers from cave-ins and collapses. Despite the best efforts of engineers, three workers would be killed boring the first tube, and six in boring the second. Further complicating construction was that the boring machines could not work as fast as expected at such high altitudes, and the productivity was significantly less than planned. The frustration prompted one engineer to comment, & We were going by the book, but the damned mountain couldn't read & . Though the project was supposed to take three years, the tunnel was not opened to traffic until March 8, 1973. Initially this tunnel (the Eisenhower bore) was used for two way traffic, with one lane for each direction. The amount of traffic through the tunnel exceeded predictions, and efforts soon began to expedite construction on the second tube (the Johnson bore). Construction began on the eastbound tunnel on August 18, 1975 and finished on December 21, 1979. The total construction cost of the project was $108 million.
