Supervisor Eric Mar requested a city study last week about how lower speed limits could benefit San Francisco. Although lowering speed limits without implementing physical traffic calming measures isn’t a panacea for safer streets, the measure does hold promise as a first step toward saving lives and implementing Vision Zero. San Francisco would follow in the footsteps of New York City, Paris, and the United Kingdom in looking at major speed limit reductions.
“We must do all that we can do to make sure that our streets are safer for our residents, and a speed limit reduction may have a significant impact on achieving this,” said Mar.
The study requested by Mar would add to a growing body of research showing how lower speed limits would reduce fatal crashes and save money. The UK Department of Transportation, which instituted a “20’s Plenty” campaign that set 20 mph speed limits as the default for residential streets, found that the chances of survival for a person hit by a car at 40 mph are half that of being hit at 30. Fatalities increase six-fold from 20 to 30 mph.
“Getting hit at 20 mph is like falling off a one-story building, but getting hit by a car at 40 mph is like falling off the fifth-floor,” said Walk SF Executive Director Nicole Schneider, who called major speed limit reductions “one of the most important next steps we can take in achieving Vision Zero.”
“We need to look towards our partner cities that have done this successfully, and model our efforts on the best practices,” she said.
Last month, New York City Mayor Bill de Blasio signed legislation requiring the installation of 20 mph “Slow Zones.” The New York State Legislature also passed a bill to lower New York City’s default speed limit from 30 to 25 mph. The default speed limit for city streets in California, unless signed otherwise, is already set at 25 mph.