WASHINGTON — For drivers along Route 50, congestion relief is another step closer to reality as the Route 50 widening project hits a milestone. But the promise of congestion relief comes with growing pains — delays due to lane closures Sunday evening into early Monday morning.

Drivers might want to make alternate plans from 7 p.m. Sunday until 5:30 a.m. Monday, when westbound traffic on Route 50 will shift to the three new lanes between Lee Road and Pleasant Valley Road. That means there will be lane closures during the transition work to the new and permanent lanes.

The Virginia Department of Transportation officials said traffic signals would be adjusted to help ease the traffic flow during those hours.  Access to any of the side streets would not be impacted during the work.

The nearly $95 million project to widen Route 50 from four lanes to six lanes (3.7 miles) from Poland Road in Loudoun County to Route 28 in Fairfax County is expected to be completed in November.

Before the widening project, just west of Route 28, Route 50 went from six lanes down to four lanes and caused major traffic congestion for most of the day, especially during the rush hours.

WTOP’s Kathy Stewart contributed to this report.