Traffic calming promises safe streets. When a neighbourhood becomes a maze of speed humps and forced turns, however, that safety is often undermined - specifically in how police officers can respond to emergencies.
The Federal Highway Administration notes that police vehicles (despite being able to bypass some traffic-calming measures) remain susceptible to reduced speeds from vertical deflection and radial turning - resulting in less effective responses.
This impact can be measured in lost emergency-service coverage. In Montgomery County, Maryland, researchers found that speed humps along an emergency-response route reduced the distance that could be reached within five minutes from 2 miles to 1.3 miles—a 35% loss. Individual treatments also produced measurable delays: FHWA reports 1.0 to 9.4 seconds per speed hump and 1.3 to 10.7 seconds per traffic circle for police cars.
Full closures create an even more fundamental problem: they eliminate a route altogether. Alameda County explicitly lists increased response times as a disadvantage of these measures, noting less efficient deployments. FHWA likewise emphasizes these sites may transfer traffic volumes by an average of 44% to side-streets and indirect routes, leaving first responders to battle heavy surges in environments that were not meant to accommodate them.
By interfering with the infrastructure, traffic calming limits an officer's ability to quickly react to an emergency situation. We must ask: where is the safety in that?
Sources
FHWA Traffic Calming ePrimer — Module 5: Emergency Services — police, fire and ambulance response impacts, including measured delays and the Montgomery County coverage study.
FHWA Traffic Calming ePrimer — Module 3, Part 3 — guidance on routing-restriction measures including full and half closures.
Alameda County Public Works — Traffic Calming Measures — identifies increased emergency response times as a disadvantage of full roadway closures.
Traffic Calming Effects In East Vancouver
Police Response, Interrupted: Traffic Calming in Vancouver
