About the Project

Project Sections

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.

What Drivers Can Expect

  • 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.
  • Starting the week of August 13, 2019, drivers traveling on I-66 West to Route 123 (Chain Bridge Road) North toward Oakton will use a new, temporary exit ramp for approximately three months. The temporary ramp will have two right-turn lanes and a traffic signal to allow drivers to access Route 123 North. The ramp from I-66 West to Route 123 South will continue to be in use during this time.
  • See project flyer for more details.
  • Drivers should expect additional changes as work progresses at the interchange. Sign up for project email updates to keep up to date.


Anticipated Schedule Dates
Clearing activities begin Spring 2018
Traffic pattern shifts begin April 2019
Ramp and bridge work begin Summer 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