3 Graphs That Explain Why 20 MPH Should Be the Limit on City Streets
Speed kills, especially on city streets teeming with pedestrians and cyclists.
The investigative news nonprofit ProPublica has produced an interactive graph that deftly conveys how just a few miles per hour can spell the difference between life and death when a person is struck by a motorist. ProPublica's Lena Groeger used data from the AAA Safety Foundation to chart the plummeting likelihood of survival as motorist speed increases.
The average pedestrian struck by a driver traveling at 20 mph has a 93 percent chance of surviving. For a 70-year-old, the chances are somewhat lower but still a robust 87 percent.
As Groeger puts it:
Once cars reach a certain speed (just above 20 mph), they rapidly become more deadly. According to [AAA's Brian] Tefft's data, a person is about 70 percent more likely to be killed if they’re struck by a vehicle traveling at 30 mph versus 25 mph.
In collisions at 30 miles per hour, about one in five pedestrians will not survive. For older pedestrians, the odds are significantly worse:
The risk of death continues to rise dramatically as speeds exceed 30 mph. At 40 mph, most older pedestrians will not survive:
In addition to much higher survival rates in the event of a collision, driving at slower speeds reduces stopping distances, making it easier for drivers to avoid hitting people in the first place.
These graphs are a compelling visualization of the data that undergirds campaigns like "20's Plenty" in the UK, where residents have demanded 20 mph streets to protect the most vulnerable. As of last fall, more than 14 million people in the UK lived on streets with 20 mph speed limits, according to 20's Plenty founder Rod King, and the campaign is now focused on extending the 20 mph limit to most streets in the country:
Stay in touch
Sign up for our free newsletter
More from Streetsblog USA
Car Crashes by City Workers Cost NYC Taxpayers $180M in Payouts Last Year: Report
A record number of victims of crashes involving city employees in city-owned cars filed claims in fiscal year 2023 — and settlements with victims have jumped 23 percent, a new report shows.
Tuesday’s Headlines Are Driving Inflation
Driving — specifically, the cost of car ownership — is one of the main factors behind inflation, according to the Eno Center for Transportation.
SEE IT: How Much (Or How Little) Driving is Going on in America’s Top Metros
Check it out: The lowest-mileage region isn't the one you'd think.
Monday’s Headlines Bring Another Setback
The Biden administration's new rule requiring states to report their greenhouse gas emissions from transportation was dealt another blow when the Senate voted to repeal it.
‘The Bike Is the Cure’: Meet New Congressional Bike Caucus Chair Mike Thompson
Meet the incoming co-chair of the congressional bike caucus — and learn more about how he's getting other legislators riding.
