The event was attended by Governor John Bel Edwards and DOTD secretary Shawn Wilson along with other state and local officials.
James Construction Group was the successful bidder.
The actual construction works of the $72m project, which also includes the replacement of the LA 42 overpass structures, are set to take place soon.
Edwards said: “We continue to move Louisiana forward with roadway projects like this one that, once completed, will benefit private and commercial transportation.
“Major projects such as this one will be limited in the near future because of the undeniable need for infrastructure funding, but my administration is accountable to our citizens and will use all possible means to continue investing in our infrastructure.”
The project is being financed from federal and state funds, including a $40m in congressionally authorised repurposed earmarks.
Wilson said: “Over 95,000 motorists travel this segment of I-10 every day, and the new lanes will help to increase safety and reduce travel times.
“This project has major benefits to the state and is another step in improving our residents’ quality of life.”
The project is expected to be completed in 2.5 years. After completion, it is set to optimise the future utility of Highland Road by reducing congestion.
Highland Road upgrade works are unfunded and do not form a part of the project.