Traffic volume reduced an average of 12 percent. Collisions reduced by 45 percent. Increased pedestrian visibility and the likelihood that drivers will yield to pedestrians. Raised crosswalks are generally preferred by fire departments over traditional speed bumps and generally slow emergency vehicles less than three seconds per hump. Neighborhood Traffic Circles involve raised islands placed in intersections, around which traffic circulates.
Motorists yield to motorists already in the intersection.
Islands require drivers to slow to a speed that allows them to comfortably maneuver around them. Traffic circles have been found to reduce speed by about 10 percent, about 100 feet on each side of the island. Intersection collisions have been reduced on average by 70 percent and overall collisions on the street by 28 percent. Emergency vehicles generally have to slow to about 13 mph, a delay of approximately five to eight seconds per circle, per truck. Neighborhood Speed Watch Program involves citizens in addressing speeding concerns in their neighborhoods.