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More U.S. highways adopting alternative interchange designs

Prepare for the ‘diverging diamond’ revolution

High-traffic highway interchanges can be a mess. Drivers trying to get onto highway on-ramps typically have to make lefthand turns across traffic—which can increase traffic congestion and car crashes. Compound those issues with a rising number of U.S. motorists and record-high travel distances, and we’ve got a highway system in need of a hero: the Diverging Diamond Interchange (DDI).

First implemented in France in the 1970s and then “reinvented” in 2000 by an American engineer, the design of the Diverging Diamond has been shown to cut the number of vehicle crashes by up to 60 percent as well as dramatically reduce traffic congestion. It essentially routes all traffic to the “wrong” side of the road as it moves over the highway, so there’s no need to cross the opposing lane while turning onto the on-ramp. The drivers have already crossed it.

Another bonus? DDIs are roughly $7 million cheaper to build than conventional interchanges. The United States’ first DDI was finished in 2009 in Springfield, Missouri. Since then, at least 29 other states have built or planned to construct the innovative interchanges. Check out how DDIs work in the video below.

Via: Equipment World