A contract has been signed for the $72 million project to widen Interstate 10 between Highland Road and La. Hwy. 73 in suburban Ascension Parish, Louisiana's transportation chief announced Thursday.

"I-10 is not only an important route for freight, but it's also a major artery for commuters who use it daily to travel between East Baton Rouge and Ascension parishes," Shawn Wilson, secretary for the state Department of Transportation and Development, said in a statement.

The work will convert the corridor from four to six lanes and take about 2 1/2 years to finish.

Construction is set to begin in early 2018 and will be done by James Construction Group, LLC.

About 80,000 motorists use the roughly seven-mile stretch daily.

The project was announced in September, well before efforts to boost state aid for roads and bridges died in the Legislature.

"This is yet another project that highlights the necessity of having a well-funded transportation system and shows this administration's dedication to using innovative means, such as design-build, to fund and construct meaningful projects," Wilson said.

"However, additional reliable, long-term funding will be needed to complete the expansion of the I-10 corridor or the construction of a new bridge," he said. The bridge is construction of a new structure across the Mississippi River in Baton Rouge.

Gov. John Bel Edwards, who backed efforts to boost state aid for transportation, echoed Wilson's comments.

"Until state lawmakers decide to make the necessary investments to help address the needs of our crumbling infrastructure, future projects like this one will be severely limited," Edwards said, also in a statement.

Design-build allows a designer and contractor to bid and work on the plan together, which speeds the process.

The widening will be funded with state and federal dollars, including more than $40 million in onetime federal money originally meant  for other work.

The project includes replacing the La. 42 overpass structures.

Follow Will Sentell on Twitter, @WillSentell.