Multiple lane closures are scheduled on the inner loop this week at Route 123 as part of the effort to extend Metrorail to Dulles International Airport and Loudoun County.

Crews plan to close three right lanes of northbound I-495 Wednesday, Thursday and Friday, from 11 p.m. to 5 a.m. each night. The closures are due to the construction of an overhead bridge that will carry Metro trains.

The closure of two right lanes on southbound 495 is scheduled for Sunday from 10 p.m. to 5 a.m.

Project officials warn that drivers should expect delays in the area during the closures.

All ramps to route 123 will be open, and police will be on site, officials said.