Here’s a fascinating chart making the rounds today, from a meta-study looking at how lane width impacts speed and (thus) crashes, injuries, and safety on streets:
The trough of the curve (the place with the least severe crashes) seems to be right between 10.5′ and 11′. That’s something that cities should keep in mind, because the default assumption in many planning conversations is that wider lanes are saver (see also: forgiveness). As it turns out, some research disputes that notion, especially in urban areas.
The report goes on to mention the potential uses of that extra couple of feet you might get from narrowing travel lanes. You could increase room for bikes, parking, pedestrians, or transit, all while making the road safer. Seems like a ‘win-win.’
