Crews work from barges in the French Broad River, as well as the riverbank, to widen the southbound bridge of Tennessee Highway 66.
Driving to the Great Smoky Mountains from Interstate 40 in eastern Tennessee has often been a frustrating adventure for motorists looking to visit the most popular national park in the U.S.
The Smokies are the country’s most visited national park, with more than 9 million visits per year and at times, particularly in the summer, it seemed that all of those visitors were driving into the park at once down one of the area’s major arteries.
The trip from I-40 South down two-lane Tennessee Highway 66 to the foothills town of Sevierville, one of the gateways into the Smokies, is only a little more than 8 mi. (13 km) long but has been the scene of tremendous traffic congestion over the years.
The entire drive south from I-40 through Sevierville and the mountain vacation town of Pigeon Forge and on to Gatlinburg should normally take about 45 minutes, but during the summer and on weekends that can stretch to a two-hour, bumper-to-bumper headache.
Last Phase of Project Underway
The situation is getting better, as the stretch of Tennessee 66 from I-40 to Sevierville is being widened to a four-lane divided highway. Six of the 8 mi. of the route were transformed to four lanes during the first two phases of the project, with the final 2.2 mi. (3.5 km), known as phase III, now under construction.
Tentative plans call for the phase III work to be completed April 3, 2015, according to Mark Nagi, community relations officer of Tennessee DOT’s Region 1.
Besides the tourist traffic that streams up and down Tennessee 66, the area has seen a lot of economic growth in recent years with large retail developments opening close to the road’s intersection with I-40. Because of that growth, the widening effort there was known as phase II and done before the middle section of the work (phase III), which is now underway.
“This corridor of state Route 66 carries more than 41,000 vehicles per day and is forecasted to carry up to 91,000 daily by 2030,” Nagi said. “The first two phases provided the necessary additional capacity that the road needed, as well as updated safety and aesthetic features.”
Nagi said the widening effort for the southern half of the road (phase I), from Nichols Street in Sevierville north to Boyds Creek Highway, was finished in November 2011, while phase II was completed a year later. With their completion, he said, the improvements in traffic flow have been quite evident.
Now, all of the work is concentrated on phase III, where construction crews under the guidance of Simpson Construction Co. Inc. in Cleveland, Tenn., are working on grading, drainage, base, paving, signalization, sidewalk construction and utility relocation. Work also has progressed on widening the northbound and southbound bridges that carry Tennessee 66 over the French Broad River.
“Phase III work started in February 2012 and I would say that, overall, the contractor is about 50 percent complete,” Nagi said. “It was initially scheduled to be finished on Oct. 31, 2014. However, unexpected subsurface conditions in the river required modifications to the proposed bridge pier foundations of each bridge.”
Completion Date Flexible
Nagi said these modifications have added several months to the project and although the completion date is currently set for next spring, other problems may extend that date further. Nagi identified one of the problems as a complex replacement of a failing section of existing storm pipe.
In addition, abnormally cold and wet weather impacted the work over the past winter, according to Nagi.
“While weather is not a justification for a contract time extension, it still has an impact on the contractors’ operations,” Nagi said. “Additionally, the area is underlain with karst [a geologic formation shaped by the dissolution of soluble bedrock, such as limestone] and is prone to sinkholes. We have treated several sinkholes within the corridor and have included stabilization measures in some areas to reduce the potential of future fallouts and settlement.”
Furthermore, the two of the bridges on Tennessee 66 being widened are located just downstream of the Tennessee Valley Authority’s Douglas Dam. Because of that, Nagi said, the river stage can fluctuate as much as 10 ft. (3 m) throughout the day. As a result, the contractor has to plan its operations around the dam’s generating schedule and for days after persistent or heavy rainfall the flow is often too swift to safely work from the construction barges.
Still, Nagi expects the job to be complete sometime in 2015.
A wide variety of equipment is being used on phase III of the road project including Cat D4GXL, D6, D6H and D8N dozers; Hitachi EX270-1 and EX270LC-5 excavators; Shugart sectional barge; and a pair of Link-Belt L5338 100-ton (90.7) crawler cranes. Beyond that, a whole range of equipment made by companies as diverse as Peterbilt, Ingersoll-Rand, Hamm, Kawasaki and Komatsu, among others.
Federal Funds Paying for Project
The widening of Tennessee Highway 66 from two to four lanes had been planned for 20 years, but only became a reality when the state was able to secure funds from the American Recovery and Reinvestment Act (ARRA) in 2009.
Sevierville city officials pushed the state hard for the project for two decades before ARRA funneled the needed funds to the TDOT. Once that happened, the Route 66 was one of the first projects put on the table for funding.
The entire cost of all three phases of the work stands at $94 million, with phase III budgeted at $32.5 million.
Two-lane traffic along phase III is still being maintained during the work, with some temporary lane closures necessary to complete the project. Nagi said that those lane closures are being scheduled during off-peak travel times.