Why 12-Foot Traffic Lanes Are Disastrous for Safety and Must Be Replaced Now

By JEFF SPECK, City Lab

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"What's the number one most important thing that we have to fight for?" I said. "You mean, besides corporations being people and money being speech?"

"Besides that."

"Well that's easy: 10-foot lanes instead of 12-foot lanes."
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The classic American residential street has a 12-foot lane that handles traffic in two directions. And many busy streets in my hometown of Washington, D.C., have eight-foot lanes that function wonderfully. These are as safe and efficient as they are illegal in most of the United States, and we New Urbanists have written about them plenty before, and built more than a few.
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States and counties believe that wider lanes are safer. And in this belief, they are dead wrong.
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Here, the takeaway is clear: AASHTO says that 10-foot lanes are just fine—for what it's worth.
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http://www.citylab.com/design/2014/10/why-12-foot-traffic-lanes-are-disastrous-for-safety-and-must-be-replaced-now/381117/