RICHLAND, Miss. (AP) — Mississippi officials have started on a $150 million project to rebuild and widen a congested suburban highway.

The Mississippi Department of Transportation will expand an 8-mile (13-kilometer) section of U.S. 49 in Richland and Florence from four lanes to six lanes. Utilities have already been moving power poles, but construction started this week on removing old curbs and gutters and widening shoulders to maintain four lanes of traffic during construction.

After that, contractors will install new culverts and improve intersections. Finally, the existing pavement will be rebuilt.

Department of Transportation Executive Director Melinda McGrath says lane closures will be timed to take place overnight and avoid holidays.

The project is expected to conclude within three years.