This Innovative Highway Design Decreases Traffic Collisions by 60%

It's tempting to think of technological advancement in terms of radical new materials or near-magical computer science--for example, the way driverless cars promise to teach artificial intelligence to drive better than humans. But just as often, new technology just makes smarter use of things we already have--for example, the way the novel "diverging diamond" interchange, or DDI, helps keep all-too-human drivers from ramming each other at high speed. By flipping two opposing lanes of traffic under a highway, the DDI design eliminates left-hand turns through opposing traffic. Left-hand turns of this sort, according to a traffic engineer speaking with Wired, are particularly dangerous and inefficient. The DDI design also makes it very hard for drivers to enter ramps going the wrong way, which, believe it or not, is a rather serious problem on the nation's highways.