Road construction begins Wednesday to improve the flow of traffic on Virginia Route 9 through historic Hillsboro, Virginia, with work expected to take at least a year and a half to complete.

More than 17,000 commuters take Va. 9 through the tiny town of Hillsboro, Virginia, every day. In late November, Loudoun County allocated $7.5 million for a $14.3 million contract, which will start out building roundabouts on either end of the road’s 0.7-mile stretch through town.

The roundabouts are critical, because they will help keep traffic moving toward detours when more intrusive one-lane operations and partial closures begin later this year.

Drivers commuting from Virginia, Maryland and West Virginia won’t be affected by road closures for several months — until late summer or early fall — but flagging operations and movement of heavy construction equipment will temporarily slow traffic on Va. 9.

The contract calls for the work to be completed within 428 days, but Hillsboro Mayor Roger Vance said there are significant financial incentives for Archer Western Construction to minimize the number of road closures and complete the project sooner.