Nighttime drivers are likely to encounter delays over the next three weeks on southbound Interstate 95 where the Virginia Department of Transportation plans to close lanes for pavement work.

From 9 p.m. to 5 a.m each night through Thursday, three lanes between Exits 161 and 163 in the Lorton area will close. The I-95 High Occupancy Vehicle lanes will be open southbound to all traffic from 6 p.m. to midnight each night. The closings will be repeated Aug. 15-18 and Aug. 22-25.

This weekend, all lanes of the Capital Beltway’s outer loop (I-495 south) are scheduled to be closed overnight at the Dulles Toll Road (Route 267). Crews working on the high occupancy toll lanes project will be placing steel beams on Friday and Saturday nights.

The beams are part of the Jones Branch Drive connection for the HOT lanes.

Starting at 9:30 each night, one lane of the outer loop will close at Exit 45, the Dulles Toll Road,. That will progress to a complete closing of the outer loop after 11 p.m. All lanes will reopen by 8 a.m. each morning.

Drivers will be detoured to Exit 45B, the Dulles Connector Road (Route 267) east toward I-66 to Exit 19B, southbound Chain Bridge Road (Route 123). Drivers will then stay right and follow detour signs back to I-495 south.

The detour may add 15 to 20 minutes to a trip during the peak overnight hour between 11 p.m. and midnight, the Virginia Department of Transportation said.

The Dulles Toll Road ramp to the outer loop also will close overnight, and drivers will be directed to continue east on the Dulles Toll Road and follow the above detour.