The next roundabout?

A new intersection design is being introduced at high volume highway interchanges in states across the U.S. The diverging diamond interchange (simulation), described by Tom Vanderbilt in a recent Slate article, reduces queue lengths and significantly reduces the number of conflict points where traffic streams intersect.

Although the design is expected to reduce wait time and improve safety, the new configuration, like the roundabouts that have been sprouting up around the U.S. over the last decade or so, has created some confusion among motorists unfamiliar with the design. In addition, the capacity improvements brought about by these new intersections will likely be cancelled out by increasing congestion and their impact on the communities that surround them. The Slate article ends with the lingering question: Can you ever truly design your way out of congestion?