I-124 Interchange

Tennessee Department of Transportation | Chattanooga, TN
interstate reconstruction

The I-124 interchanges located in downtown Chattanooga provide access to the central business district of the city. They also allow for access to various tourist attractions such as the Tennessee Aquarium, Chattanooga Convention Center, the Chattanooga Look-Outs baseball stadium and the corporate headquarters of Blue-Cross Blue-Shield of Tennessee. The existing system constructed in the late 1960s had several operational deficiencies and no longer provided an adequate level of service for the community.

Benesch worked closely with the Tennessee Department of Transportation to study and provide final design services for three urban interchanges along I-124. The design resulted in major improvements to increase the vehicular capacity of I-124 while improving the safety and ease of access to the downtown core of Chattanooga. For the project, Benesch conducted traffic data collection, as well as transportation planning and traffic modeling and analysis.

The design improvements included nine new bridges, 41 retaining walls and new ramp access points to 6th Street and Carter Street near the Chattanooga Convention Center. A project landscape committee worked closely with local stakeholders to develop an overall landscape plan for the hardscapes of the project. Benesch also created functional design plans, cost estimations and photo simulations for the project.

At the time of construction, this project was the single largest let project in TDOT’s history at $126 million. Benesch’s engineers are part of the project’s CEI team, working closely with the contractor and TDOT to construct the project.


  • 2021, Honor Award, American Council of Engineering Companies - Tennessee