With the aim of improved safety and access for residents and commuters along a busy section of I-40 near Jackson that’s home to one of the state’s top tourist destinations, Gresham Smith delivered on a critical widening and interchange reconstruction design project for the Tennessee Department of Transportation (TDOT). The resulting reconstruction and intersection improvements allows the local community to better manage current and future traffic demands.
Opened to the public in 2021, the roadway project features a widening of a 2.9-mile section of I-40 from four to six lanes from west of the U.S. 45 Bypass to east of North Highland Avenue (U.S. 45). Additional improvements include:
- New eastbound and westbound auxiliary lanes on I-40 to reduce weaving conflicts
- Two new bridges along I-40
- Intersection reconstruction at U.S. 45 Bypass and at SR 5 (North Highland Avenue)
- A reconstructed intersection at U.S. 45 Bypass and Casey Jones Village
For the local community, the highlight of the project is a new single point urban interchange (SPUI) that will provide a new gateway entrance into the historic city center in Jackson.
single-point urban interchange
widening of I-40
The Future Starts TodayThe U.S. 45 Bypass is an important north-south connector in the City of Jackson as well as regionally. It’s the primary route from the Jackson Central Business District to I-40, and it carries a large portion of truck and through traffic coming from Mississippi and Tennessee counties south of Jackson. The route is densely commercial, including Casey Jones Village, which is one of the state’s top 10 tourist attractions.
Increased development along U.S. 45 Bypass has resulted in steadily increasing traffic volumes along I-40 for many years that’s expected to increase to 70,290 vehicles per day by 2033. To make way for this future growth, the design team realigned the intersection of the U.S. 45 Bypass at Casey Jones Lane and added turn lanes to allow left turns from Casey Jones Lane to more easily access I-40. Left turns from Casey Jones Lane were not allowed in the existing intersection layout.
Slide to see the proposed intersection improvements at US 45 Bypass/SR 186 at Casey Jones and Carriage House Road vs. the completed intersection in July 2021.
Time on the Mind
The new interchange at I-40 and SR 5 (Exit 82) is a key feature of this project as it provides a new access route to the city of Jackson as well as an innovative approach to a busy interchange. After weighing all the alternatives, TDOT gave approval to design a Single Point Urban Interchange (SPUI), a creative solution that’s designed for situations where there is a need to move large volume of traffic efficiently through an area with limited amounts of space. With a SPUI, all the opposing traffic comes to one single point, and it’s maneuvered through that one point more efficiently and faster. Before, it was estimated that it would take about 10 minutes to go through the intersection. With our innovative approach in place, that travel time has been cut down to 2 minutes, according to WBBJ TV report.
Slide to see the proposed rendering of the I-40/N. Highland Ave. SPUI vs. the completed SPUI and exit ramp.
On the Fly
The development of construction plans for the section of I-40 west of the U.S. 45 Bypass interchange to east of the North Highland Avenue interchange was done on an extremely fast-track schedule to meet TDOT’s funding obligations. We were given notice to proceed in November of 2016, and final construction plans were turned in June of 2017.
Simultaneously with the I-40 project, we also prepared the preliminary, right-of-way and construction plans for the improvement of the intersection of SR 186 at Casey Jones Drive/Carriage House Lane, which tied into the ramps for the reconstructed interchange for I-40 at SR 186. The two projects were bundled in TDOT’s August 2017 letting.
For the PeopleThroughout the design process, Gresham Smith engaged with the community every step of the way to explain the value that this project could have on the future growth of the local community. In the initial planning for the project, the project team weighed a number of alternatives for the interchange modification configuration. During the process, then-Jackson Mayor Jerry Gist wrote a letter to TDOT expressing his support for the SPUI concept, stating the following:
“The existing interchange at Exit 82 is currently burdened with traffic capacity issues and vehicular crashes due to its current cloverleaf 1964 design. … The proposed widening of I-40 through Jackson will have a dramatic, positive impact on the city. … Not only will improvements along I-40 positively impact the city, the modifications of I-40/US 45 interchange will also dramatically improve the operations and safety of these two state and city routes through Jackson.”