I-64 Interchange at Route 15, Zion Crossroads
|Construction of a diverging diamond interchange (DDI)|
Project at a Glance
Design work October 2012; construction June 2013
Est Completion Date
April 15, 2014
$6.883 million design-build contract
Lengths and Limits
Corman Construction Inc. of Colonial Heights
During the week of May 20, Corman Construction, Inc., contractor for the Virginia Department of Transportation, will install message boards and other signs, construction fencing and erosion controls in the project area, with no impact to traffic.
Motorists will encounter lane closures on Route 15 beginning Wednesday, May 29, as construction gets under way on the project. Work will begin in the Route 15 median, requiring closure of the northbound and southbound left lanes. The traveling public is encouraged to drive with caution through the work zone.
The purpose of this project is to improve the I-64 interchange on Route 15 at Zion Crossroads (exit 136).
In 2007, VDOT identified a need to increase the capacity of the I-64 off-ramps at the Route 15 interchange, which—combined with a forecasted increase of traffic due to the area’s commercial growth—prompted a study of potential interchange options.
In addition to the diverging diamond interchange (DDI), VDOT analyzed the construction of a single-point urban interchange, improvements to the existing diamond interchange, and a no-build alternative. The clover-leaf interchange was not included based on the amount of land acquisition it would require.
Overall, the diverging diamond interchange produced the best results based on today’s traffic volumes as well as those projected for 2035.
What is Proposed?
VDOT proposes to reconstruct the 0.49-mile stretch where Route 15 meets I-64 (exit 136) as a diverging diamond interchange (DDI). By briefly shifting vehicles to the opposite side of the road, this innovative interchange design eliminates traditional left turns that must cross over oncoming traffic. The DDI improves safety by reducing the number of spots where vehicles could collide and can handle more than 600 left-turn movements per hour, twice the capacity of a conventional interchange.
The diverging diamond interchange is new to the U.S. Though the design originally appeared in the 1970s in Versailles, France, America’s first DDI was built in 2009 in Springfield, Missouri. Since that time, two others have been completed in Missouri, as well as one each in Utah and Tennessee.
News release: Zion Crossroads Construction Begins May 29
News release: Construction to Start at Zion Crossroads in May
YouTube video simulation of proposed interchange design
Diagram of proposed interchange design (321 KB)