3 Alerts From the DDI Tag


NMA E-Newsletter #281: Members Share Thoughts on Emerging Transportation Designs

In last week’s newsletter (#280: Can it really be Safer to Drive on the Wrong Side of the Road?) we discussed several emerging, “alternative” interchange and intersection designs: the Diverging Diamond Interchange, the Displaced Left Turn Intersection and the U-Turn Intersection. We asked if you’ve ever driven one and what you thought about them overall. […]

NMA E-Newsletter #280: Can it really be Safer to Drive on the Wrong Side of the Road?

They’re rebuilding the main intersection here in Waunakee, transforming a traditional signalized intersection into a roundabout. Our office is about block away from the action, so we can hear them working, and much of the traffic is getting diverted onto our street for the duration of the project. The roundabout is a relatively new fixture […]

NMA Email Newsletter: Issue #69

The Diverging Diamond Interchange The concept was developed in France. (Insert joke here.) Only one such interchange exists in the United States: Springfield, MO activated a diverging diamond interchange (DDI) last June, and says it has seen a 60 …