Eliminating the Dreaded Left Turn

The FHWA says that 40% of all traffic accidents happen at intersections, and many of those are caused by left turns. A new type of intersection called the "diverging diamond" takes left turns out of the picture.

1 minute read

October 12, 2011, 12:00 PM PDT

By Tim Halbur


Slate's Tom Vanderbuilt looks at the left-turn problem, and the solution proposed by Gilbert Chlewicki. Here's how it works:

"As the eastbound driver approaches the highway interchange (whose lanes run north-south), traffic lanes "criss cross" at a traffic signal. The driver will now find himself on the "left" side of the road, where he can either make an unimpeded left turn onto the highway ramp, or cross over again to the right once he has gone under the highway overpass."

Monday, August 1, 2011 in Slate

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