Diverging Diamond Interchange (DDI)

A Diverging Diamond Interchange (DDI), also known as a double crossover diamond (DCD), is a diamond interchange that crosses traffic to the opposite side of the road across an interchange so vehicles have unimpeded movement onto the freeway ramps. Left-turn movements, which are a typical challenge with standard four-way interchanges, are eliminated with a DDI.

Why DDI?

The innovative DDI design reduced potential points of intersection traffic conflicts and improves traffic flow and safety.

 

Safety Benefits

  • Fewer conflict points
  • Wrong Way entry to ramps extremely difficult
  • Reduced speeds through intersections
  • Minimal driver confusion


UNDER DESIGN OR CONSTRUCTION

I-75 at SR 20/McDonough-Hampton Rd

Henry County

This project will convert the existing interchange into a Diverging Diamond Interchange.


SR 22/JR Allen Pkwy at Bradley Park Dr.

Muscogee County

This project will convert the existing interchange into a Diverging Diamond Interchange.


 

 

In Operation

ProjectLocationResources
I-285 at Ashford Dunwoody Road
DeKalb County
I‐85 at Pleasant Hill Road
Gwinnett CountyVIEW WEBPAGE
I‐85 at SR 140/Jimmy Carter Blvd
Gwinnett CountyVIEW WEBPAGE
I‐75 at Wade Green Road
Cobb County
I‐95 at SR 21
Chatham County
I‐75 at Windy Hill Road
Cobb County