Work on improving the bottleneck and dangerous "Split" of I-24 and I-75 is expected to start in the summer of 2019.
Jennifer Flynn of TDOT said it will be a Design-Build project and the contract is not expected to be awarded until later this year.
Then the work would have to be designed before it could get underway, she said.
Ms. Flynn said, "Design-Build means a project delivery method that combines all or some portions of the design and construction phases of a project - including without limitations design, right-of-way acquisition, regulatory permit approvals, utility relocation, and construction – into a single contract. TDOT will clearly define the standards and general specifications they expect for a project, and the Design-Builder works to satisfy those requirements. The Department is utilizing the Design-Build concept to expedite project delivery and streamline design processes.
"The Department is currently developing a 30 percent plan for the project that gives basic design information on how the Department thinks the project should be built. The procurement phase will begin this summer (2018) with a Design-Builder selected for the project later this year. The successful Design-Builder prepares all engineering drawings to define cost/function (during/after construction).
"The public will probably not see work on this project until summer of 2019 because the Design-Builder will have to finish designing the project, acquire any necessary right-of-way and obtain all necessary permits."
She said the project consists of widening existing roads and ramps, increasing ramp radii to provide 55 mph design speed, reconfiguring I-24 ramps to enter and exit I-75 from the right side, shifting the interchange to the west and modifing the Welcome Center area traffic circulation.
The project will also include new bridges for Spring Creek Road, McBrien Road and Moore Road over I-24 as well as Interstate bridges. Retaining walls will be required along I-24 and between I-75 and the Welcome Center Area.
Only minor design work, such as resurfacing and restriping, is anticipated on North and South Terrace with the exception of slope mediation on North Terrace near the Belvoir Road Intersection.
Ms. Flynn said, "The project’s primary purpose is to provide present and future congestion relief, reduce the high crash rate and to address the deficiencies of the existing interchange."
The I-75 North Exit 1 reconfiguration project currently underway by the city of East Ridge was designed with the future I-75/I-24 interchange project in mind, so it will not be affected.