Cumberland Gap Tunnel (US 25E)
The Cumberland Gap Tunnel carries four-lanes of U.S. Route 25E under Cumberland Mountain between Kentucky and Tennessee.Planning
Engineers on the Cumberland Gap Tunnel project hoped to facilitate safer travel along U.S. Route 25E, to restore and preserve one of the nation's most historic routes, enhance recreational opportunities along the Gap and return time to the days when Daniel Boone blazed a new trail, later called the Wilderness Road, for settlers. (5)The 2.3-mile modern-day highway was formed in 1916 and modernized in the 1960s, (1)(8) however, by the 1950s, it was becoming obvious the 2.3-mile crossing over Cumberland Gap, linking Middlesboro, Kentucky to Cumberland Gap, Tennessee, was becoming a death trap. "Massacre Mountain" was one of the more popular and grisly nicknames, in part because of the number of motorists killed along it. (5)(11) The first discussion of a tunnel under Cumberland Gap was first initiated by the National Park Service in 1956. During the next decade, studies were conducted that recommended a tunnel to improve the roadway without damaging the scenic and historic significance of the Cumberland Gap.
In 1979, geologists examined exposed rock on the surface of the mountain and identified the different rock types. (1) Next, a small-diameter horizontal core hole, 2000-feet long, was drilled to provide even more geologic detail. Afterwards, a pilot tunnel, 10-feet high, 10-feet wide and 4100-feet long was excavated. This revealed many characteristics of the mountain that would later pose challenges to the Cumberland Tunnel project. Thick clay infillings, limestone formations, caves and a lake were encountered. Numerous underground streams were a major challenge as well. This was the first year that Congress appropriated money for the project before most of the funding was removed by the Carter administration. (11)
The battle to improve the deadly U.S. Route 25E crossing, however, would drag on for two decades. Battles were raging in Congress over the appropriation funding, followed by an all-out funding freeze by the Executive Branch in 1984 during the Reagan administration. (11) An annual vote was taken on whether to continue paying for the design and construction of highway projects. At the urging by U.S. Rep. Hal Rogers, a member of the House Appropriations Committee, the Cumberland Gap Tunnel project eventually became part of a highway budget that did not require annual reauthorization. Another boost was the commitment of at least $2 million by the states of Kentucky and Tennessee to operate and maintain the finished tunnels, which received Reagan's approval. (11)
Construction
Engineers began drilling a smaller "pilot" tunnel in 1985 to better understand the layers of rock that formed Cumberland Mountain, (11) which measured 10 feet high, 10 feet wide, and 4100 feet long. (2) On June 21, 1991, construction began on the actual Cumberland Gap Tunnel project with the blasting of the northbound tunnel. (3) This was one of the most important, and expensive public works projects that was ever carried out in the state of Kentucky, as it replaced a narrow, deadly and winding road through the historic Cumberland Gap. (11) The estimated cost was anywhere from $250 million to $270 million, a probable range as the project was so large that even federal highway officials couldn't pinpoint an exact dollar amount. By the time construction began, the two-lane route over the Gap was carrying twice as much traffic as it was designed to handle, and carried an accident rate six times higher than on similar federal highways. (11)Excavation then began on the main tunnel tubes, on-going from both sides of the mountain, and was met with some obstacles. While constructing a drainage system for the huge caverns that lie just outside of the tunnel walls, workers discovered that one of the ca ves had become clogged with rock. The blockage forced water to blow out a small chunk of the northbound tunnel. (11) The discovery of numerous caves, some of which were only big enough for a slim worker with no hardhats and belts to fit through, slowed the tunnel excavation from the estimated 2.5 year job it was expected to take to three years.
On July 9, 1992, the two sides of the tunnel met in precise alignment in the center. (3) The project was completed 1,947 days after the initial blast at a cost of $280 million, more than twice an original early-1980's estimate of $156 million. (8)(9) On October 18, 1996, a ceremony involving officials from Virginia, Kentucky and Tennessee celebrated the opening of the Cumberland Gap Tunnel. (11)
Seventeen years in the making, the Cumberland Gap tunnel project has spurred highway expansion in three states, hopes for tourism in small communities near the Gap, and dreams of restoring the wilderness trail that Daniel Boone blazed in the 1700s. The tunnel is "the most significant thing that has happened there since Daniel Boone began to bring settlers through the Gap." (9)
- U.S. Rep. Hal Rogers
- U.S. Rep. Hal Rogers
The tunnels, each carrying two-lanes of traffic, were bored through 4600-feet of solid rock. (11) The tunnels, at the tallest point, are 30-feet high. (2) Cross passages located every 300-feet connect the two tunnels; each are equipped with fire extinguishers and phones for emergency use. Since the mountain releases 450 gallons of water every minute, thick PVC liner around the tunnels ensures that the bores stay dry. There are also 32 jet-powered fans every 600-feet that keep the air circulating in the tunnel; air quality is monitored constantly by electronic sensors. Variable message board signs are posted in the Cumberland Gap vicinity to warn drivers of weather conditions that could rapidly change, or of any restrictions in the tunnel. AM and FM stations can be overridden with emergency messages as well. (1)(2)(4)
Along with that, the Cumberland Gap Tunnel has dedicated fire, rescue and towing crews on-call 24-hours a day. (1)(2) Separate water storage tanks were constructed for use in the event of a fire in the tunnel as well. Portal buildings at tunnel entrances house state-of-the-art ventilation, lighting and communications equipment, as well as closed-circuit cameras and magnetic loop detectors for traffic control.
Included in the project were five-miles of new four-lane approaches to the tunnels, two interchanges, one for the Cumberland Gap park entrance and another with US 58, seven roadway bridges (four in Kentucky, three in Tennessee), a 200-ft. railroad steel box girder bridge, two pedestrian bridges on hiking trails, three parking areas and the repair of an abandoned railroad tunnel under old U.S. Route 25E that later hosted electrical, telephone, cable and water lines under the new U.S. Route 25E and US 58 interchange. (1)(2) Vehicular crossovers at tunnel entrances were constructed to allow for two-way traffic through the tunnel if one tube has to be closed.
The use of sandstone masonry, Cor-Ten weathering steel, concrete blended with earth-tone elements and many native trees that were planted help mix the modern with the natural beauty of Cumberland Gap. As an offshoot of the Cumberland Gap Tunnel project, Kentucky spent nearly $70 million to complete upgrades to U.S. Route 25E into a four-lane highway from Barboursville to Pineville. Tennessee is completing upgrades to U.S. Route 25E.
Also of note, while the former U.S. Route 25E alignment crossed the Cumberland Gap from Kentucky to Tennessee, it briefly touched Virginia. With the new tunnels completed, however, it no longer traverses through three states, coming within yards of the Virginia state border. According to Kentucky transportation historian, H.B. Elkins, US 58 had a major rerouting in the Gap area as well. A portion of old U.S. Route 25E in Tennessee was resigned as US 58 so that it could make a proper connection to the new U.S. Route 25E alignment. (6)
The asphalt on U.S. Route 25E's alignment through Cumberland Gap was all but demolished in 2002, with the earth re-contoured to resemble a wagon trail at a cost of $5 million. The National Park Service used tons of rock excavated from the tunnel to contoured the topography to what it resembled in the 1700s. This is to simulate its appearance when settlers crossed the Cumberland Gap into Kentucky from Tennessee when the crossing was known just as the Wilderness Trail. (10)(11)
Sources
1. "Bridging the Gap." News-Sentinel (Knoxville) 14 Oct. 1996. Aug. 2004: A6.
2. "The Cumberland Gap Tunnel." Eastern Federal Lands Highway Division. Federal Highway Administration. 21 June 2005 Article.
3. "The Cumberland Gap Tunnel." National Park Service 10 May 1999. 21 June 2005 Article.
4. "Cumberland Gap Tunnel ITS Project Home." Kentucky Transportation Center. 20 June 2005 Article.
5. Droz, Robert V. "Old US 25E: Crossing the Cumberland Gap." U.S. Highways 20 June 2002. 20 June 2005 Article.
6. Elkins, H.B. "Cumberland Gap Tunnel Opening Ceremony." Online posting. 21 Oct. 1996. 19 June 2005 Post.
*7. "Parkway System & Cumberland Gap Tunnel Project Selected Kentucky's Top Transportation Infrastructure Projects of 20th Century." 6 Dec. 2002. 19 June 2005 Article.
8. "Touch of the unknown makes mountain tunnel risky." Miami Herald 7 Mar. 1986. 20 June 2005 Post.
9. "A tunnel to the future." Herald-Leader 13 Oct. 1996. August 2004: A1.
10. "Will underground passageway boost tourism in the area? Officials say yes." News-Sentinel (Knoxville) 14 Oct. 1996. August 2004: A6.
11. Dias, Monica. "Cutting through the Gap." Kentucky Post 13 July 1996. 28 Nov. 2007: 1K.
tractor trailer accident lawyer nashville tn | July 23, 2009, 12:03
The Cumberland Gap Tunnel is a great example of civil engineering marvels in the history of United States. This was a humongous effort that involved lots of coordination, time and quality labor before it could be successfully completed. As a result of it, the U.S. Route 25E lanes facilitated easy travel between Kentucky and Tennessee. |
My brother was involved in this project and he told me what an intense project it was.