Slow speeds, tight turns, the loud suspension shudder as yet another hump blocks the road - a school bus tries to navigate the maze of traffic calming measures. It does not easily succeed. With the introduction of concrete barriers, raised crossings, and chicanes comes a negotiation of awkward angles; and simply trying to reach the parking lot is an everyday ordeal.
In 1993 the Kent County Council conducted an extensive trial test of buses (mini, single-decker, and double-decker). With each raised hump and junction slow speeds were experienced, with the vehicles having to reduce acceleration by 5 MPH to avoid jostling passengers with too much force. Increased gradients caused excessive braking (which impacted mechanical performance and part longevity), and damage from suspension grounding was also seen.
Additionally, the Federal Highway Administration identifies buses as being specifically affected by traffic calming because of their longer wheelbases. Its research found that these vehicle can experience losses of up to 9.4 seconds per speed hump, 9.2 seconds per speed table, and 10.7 seconds at traffic circles; and, with humps often spaced just 153 metres apart on long streets, repeated slowdowns can significantly accumulate over a school route.
This creates a longer, less comfortable ride - with students paying the price.
Sources
Kent County Council, Road Humps and Buses
Federal Highway Administration, Traffic Calming
Federal Highway Administration, Traffic Calming
Traffic Calming Effects In East Vancouver
School Bus Slowdowns: Are Traffic Calming Measures Delaying East Vancouver Commutes?
