The Arkansas Highway and Transportation Department plans to hire a consultant to study whether the state could convert Interstate 40 from North Little Rock to Memphis into a toll road.

 The Arkansas Highway and Transportation Department plans to hire a consultant to study whether the state could convert Interstate 40 from North Little Rock to Memphis into a toll road.

The study was authorized this week by the Arkansas Highway Commission, which says more revenue is needed to pay for road improvements. The Arkansas Democrat-Gazette reports (http://is.gd/MYHW9R ) that the state would still need to gain federal approval to convert the interstate into a toll road.

A federal program allows interstates in up to three states to collect tolls to fund necessary road improvements. Interstate 95 in Virginia and Interstate 70 in Missouri participate in the program, while South Carolina has received approval under a separate federal program.