From the Virginia Department of Transportation (VDOT):
The ramp from Route 123 (Chain Bridge Road) North to I-66 East will close temporarily beginning during the daytime hours on or about Friday, May 13. Drivers will travel about 500 feet farther north on Route 123 to make a right turn at the traffic signal, then use a temporary ramp to reach I-66 East. This traffic pattern is anticipated to be in place through summer 2022 while construction of the Route 123/I-66 Interchange advances as part of the Transform 66 Outside the Beltway Project.
When complete, the reconstructed Route 123/I-66 Interchange will provide direct access to and from the new Express Lanes for both eastbound and westbound travelers. A new shared-use path through the interchange will provide connection between the new I-66 corridor trail and planned trails in the City of Fairfax.