I-75/I-24 Interchange

The Challenge

The proposed TDOT I-75/I-24 Interchange design-build project was one of vast size and scope, featuring multiple bridge and ramp widenings and repairs, 14 new bridges, 21 new retaining walls and a noise wall, lighting, safety and mobility upgrades, and Welcome Center traffic modifications. Created for a densely traveled area, the design-build had to be the most cost-effective, fastest, and safest option for the contractor, owner, and community. During the project's design phase, virtual roadblocks tested Barge Design Solutions with right-of-way challenges, environmental concerns, and an earlier proposed bridge plan that exceeded the budget. It would take innovative solutions to secure the winning bid and move the project forward.

The Solution

The Barge team first addressed the initial TDOT proposed bridge plan at the I-75/I-24 split with a brilliant design flip. By moving the more heavily traveled I-75 roadway to the ground and designing concrete overpasses or new alignments in lieu of steel for new I-24 ramps, the contractor could deliver the project faster and more efficiently, minimizing cost, time, and safety risks.

The second challenge involved right-of-way, where new wider ramps would be built. Purchasing land for the ramps could take months to finalize, so the Barge Design Solutions team proposed to build new ramps right next to the old ones within the existing right-of-way to expedite the process. Barge also proposed that precast MSE retaining walls, a noise wall, and bridge beams be fabricated in an outside controlled setting for high-quality delivery to the site. By using precast elements in the design, it allowed for a reduction in time to the overall construction schedule.

For environmental concerns, eight wetlands had to be moved from the area of construction, requiring permitting and coordination with authorities. Instead of buying credits for rebuilds in the West Tennessee Wetland Mitigation Bank, Barge looked to move the wetlands nearby, finding a location directly outside the site's boundary.

The Result

Finishing the I-75/I-24 Interchange project ahead of schedule, Barge's experience and innovative planning maximized space, minimized traffic disruption for improved safety and timelines, and revised the number of proposed bridges from 14 to 12, reducing the budget. Wetlands and endangered plant species were preserved with minimized costs. And nearby resident requests were met with reduced road noise and improved aesthetics.