First, for those choosing to cycle, the reduction of risk is significant, as shown in the National Institute of Transportation and Communities study, a Canadian study, and several other studies.
The actual measured reduction in risk ranges from 50% to 90% depending on pre-existing conditions and the particular road configuration and traffic context. The chart below, from the Canadian study, says it all quite clearly.
For those choosing to drive, the traffic calming smooths traffic flows and reduces speeding, lessening both risk of collision and severity of damages in a collision. See the Benefits post for more information.
For those choosing to walk, traffic calming also reduces vehicular speed, lessening conflict at crossings. Should a collision occur, lower vehicle speed implies less severe injuries.
A memo from the New York City Mayor’s Office way back in 2011 summed up early experiences quite well. “When protected bike lanes are installed, injury crashes for all road users (drivers, pedestrians, cyclists), typically drop by 40 percent and by more than 50 percent in some locations.”
The defense rests.