About the Project

Route 123 Interchange

Major reconstruction is planned for the Route 123 Interchange as part of the Transform 66 project. The new interchange design:

  • Provides access to and from the future express lanes from I-66 East and West
  • Improves safety at the interchange
  • Connects the City of Fairfax and the planned George Snyder Trail with the new shared use path and neighborhoods in Oakton with a grade-separated trail through the 123 Interchange

Get a closer look at what’s planned through the Transform 66 Interactive Map.

What Neighbors Can Expect

  • Noisy construction activities such as bridge demolition and pile driving will be avoided at night, when possible. Noise to expect at night includes back-up alarms on equipment and trucks, which is necessary to protect worker safety.
  • Lighting of the construction work area will be directed to minimize light pollution for nearby residents.
  • Project emails and website will be used to communicate major traffic switches or nighttime work.

Route 123 Interchange Exit Ramp Demolition

The flyover ramp from I-66 West to Route 123 South is being demolished to make room for future Express Lanes ramps and shared-use path at the Route 123 Interchange. Nighttime demolition activity at this location finished on March 3. Remaining demolition activity is expected to occur during daytime hours.

The project team is taking steps to minimize demolition noise, but some loud noise is unavoidable. Project noise levels are monitored by VDOT during demolition activity.

Additional Traffic Pattern Change Beginning March 21, 2020

  • The Route 123 Interchange is being re-constructed to provide direct access to and from the future eastbound and westbound I-66 Express Lanes. These improvements require a series of traffic pattern changes during construction.
  • Beginning on or about Saturday night, March 21, 2020, drivers on southbound Route 123 will access I-66 East using two traffic signal-controlled left-turn lanes to reach a new ramp, then merge onto the current ramp from Route 123 North to I-66 East (see graphic)
  • Two travel lanes will continued through the interchange in each direction
  • Drivers traveling from northbound Route 123 to I-66 East should be alert for traffic merging onto the ramp from the left
  • The old loop ramp from Route 123 South to I-66 East is being demolished.
  • See traffic advisory for more details.


Anticipated Schedule Dates
Clearing activities begin Spring 2018
Traffic pattern shifts begin April 2019
Ramp and bridge work begin Summer 2019
Demolition of ramp from I-66 West to Route 123 South Winter 2019
Express lanes open December 2022


Concept plans (I-66) - PDF, 13.7MB
Concept plans (Rt. 123) - PDF, 12.6MB
Cross sections - PDF, 16.9MB
Plan and profile - PDF, 36.4MB
Planned I-66 trails near Route 123 - PDF, 1.5MB
Upcoming traffic changes (April 2019) - PDF, 424KB
Upcoming traffic changes (July 2019) - PDF, 396KB
Construction Update Meeting on September 4, 2019 Flyer - PDF, 1.3MB
Route 123 (Chain Bridge Road) South Flyover Ramp Demolition - Jan, 2020, - PDF, 5.6MB
Traffic Pattern Changes for I-66 East to Route 123 North on Feb. 21 - Website
Traffic Changes at Route 123/I-66 Interchange Starting on or about March 21 - Website
Flyer on Rose Forest Drive Closure and Detour (Sept. 2020) - PDF, 1.7MB