“Some Communities Use 'Speed Bumps’, Why Can't We?”

A speed bump is a bump of asphalt about a foot wide, 3 to 4 inches high, and placed laterally across the traveled portion of the road. The speed bump poses an increased hazard to the unwary....A challenge to the daredevil....A disruption of the movement of emergency vehicles.... The cause of an undesirable increase in noise....And a real problem for snow removal.

Because speed bumps have considerable potential for liability suits, Michigan has officially rejected them as a standard traffic control device on public streets.

Tests of various experimental designs have demonstrated the physical inability of a speed bump to successfully control the speeds of all types of vehicles. The purpose of a speed bump is to make the ride over it uncomfortable for drivers, thus encouraging them to reduce their speed. The driver of a softsprung sedan can experience a more comfortable ride over a speed bump at a low or high speed, because of the vehicles' suspension system. On the other hand, a vehicle with tighter suspension (school bus, fire engine, moving van, etc.) must virtually stop before going over a speed bump.

Often these devices are suggested to combat speeding or "through" vehicles. If speeding is the alleged problem, studies must be conducted to determine the extent of the problem. Other, more effective steps can be taken to decrease the speeds of vehicles or number of speeders. Often, there are a few speeders who cause most of the problems. If "through" traffic is the problem, it is often the symptom of a traffic related problem on a nearby major street. The real problem should be determined, analyzed and corrected.

The control of speeding in residential neighborhoods is a widespread concern which requires resident compliance and patience, and persistent law enforcement efforts....Not speed bumps.


* This information is provided by the TIA (Traffic Improvement Association).