This is what the Virginia Department of Transportation will do to reduce the worst new construction zone congestion in the D.C. region: 1) Restore the Exit 49 ramp on the outer loop of the Capital Beltway at I-66 to two lanes, 2) add a fifth lane along westbound I-66 at the interchange.

This part of the 495 Express Lanes project is a tight work zone, where the obstacles include an old ramp from the inner loop that must be demolished, the Orange Line tracks and the Dunn Loring Metrorail station. To accomplish the ramp restoration and the I-66 widening, VDOT plans to reduce the lane widths on westbound I-66, remove the shoulders in the interchange area and shift traffic near the station.

If this goes as the planners hope, the new pattern will remain in place until the interchange reconstruction is complete this fall. The Express Lanes are scheduled to open by the end of the year.

To accomplish this latest traffic shift in the work zone, VDOT is planning some major work for this weekend.

Weather permitting, Exit 49 and several lanes on westbound I-66 will be closed from 9 p.m. Saturday till 9 a.m. Sunday. Drivers will be detoured. During those hours, workers will restripe the pavement markings and move barriers to install the new fifth lane and restore the ramp lane. All lanes will be reopened by 9 a.m. Sunday, VDOT said.

If bad weather interferes, the work will be rescheduled.

The initial change that narrowed the outer loop ramp to westbound I-66 was made to ease traffic congestion on the other side of the Beltway and along I-66 in the area of the interchange. But the traffic didn’t behave as the planners had predicted. Outer loop traffic sometimes backed up to the American Legion Bridge and beyond. Drivers on Route 7 and the Dulles Toll Road in the Tysons Corner area were among those affected.

Related stories:

VDOT looking to ease I-495/I-66 traffic

Express Lanes project closing Route 7 ramp