Northern Virginia’s first Diverging Diamond Interchange (DDI) at Interstate 66 and Route 15 will be one step closer to completion once the new traffic signal mast arms are installed at Route 15 and Route 55, according to the Virginia Department of Transportation. Lane closures at the intersection, as well as intermittent full closures up to 15 minutes each will occur to facilitate the work.
Lane closures will occur between 9 p.m. Thursday, July 20 and 5 a.m. Friday, July 21. Total stoppages lasting no more than 15 minutes each will occur between midnight and 5 a.m. Prince William County Police will be on site to direct traffic.
Also, paving around the intersection is scheduled to occur the nights of Thursday, July 20 through Tuesday, July 25.
All work is weather permitting. More information is available on the project page.
The DDI’s innovative design shifts vehicles to the opposite side of the road and eliminates left turns that cross oncoming traffic. Two-phase traffic signals at each end of the interchange reduce time spent at red lights and move twice the number of vehicles as a traditional diamond interchange. VDOT has completed DDIs in Louisa and Roanoke, and has two more in the works in Blacksburg and Stafford.