Slow Zones Will Save Your Life, and Will NOT Dump Traffic in Your NIMBY Backyard

Streetsblog New York City just accused the The Brooklyn Paper of manufacturing controversy over slow zones in Brooklyn with one of its “trademark neighbor-vs.-neighbor stories.”  In covering weekend public workshop on a potential 20 mph zone in Park Slope, the Paper focused on “Greenwood Heights activists”  who apparently stated that a Park Slope slow zone would divert unsafe driving from one neighborhood to another.

In fact, when London adopted 20 mph slow zones (see graphic), traffic injuries and deaths declined–not only in the zones, but even a little bit on streets right outside the zones. Moreover, there was no increase in deaths or injuries outside the slow zones. So there was no “casualty migration” to nearby roads.

“It would be great to see a blanket 20 mph speed limit — pioneered by NYC DOT in the Bronx neighborhood of Claremont — extend to many neighborhoods at once,” Ben writes. “But if Park Slope gets a slow zone before Greenwood Heights, or if Greenwood Heights gets a slow zone before Park Slope, research suggests both neighborhoods will still be better off.”

Image: Effect of 20 mph traffic speed zones on road injuries in London, 1986-2006: controlled interrupted time series analysis | BMJ.