Streets should be designed for the desired speed, using built-in traffic calming measures such as roundabouts, narrower street widths, chicanes, medians, etc.
In Lexington, speeding is a common complaint on wider streets, particularly those classified as collectors. These streets, which are wider by design, create faster vehicle speeds, regardless of the posted speed limit, due to the driver’s perception of a wide open space. In contrast, streets should be designed such that bicyclists, pedestrians, and mass transit riders feel comfortable and encouraged to freely share the space with automobiles. This can be accomplished through the appropriate use of traffic calming features such as roundabouts, medians, street trees, chicanes, reduced building setbacks, shorter block lengths, and narrower street widths.
Reductions in vehicle speed significantly decrease injuries and fatalities for both vehicular and non-vehicular users alike. Employing traffic calming techniques such as those listed above increases motorists’ attentiveness to the surrounding context, and if considered early in the design process, they carry the additional benefit of eliminating the need for costly traffic calming retrofits.
Studies have shown that each 1-mph reduction in average traffic speed reduces vehicle collision rates by 3 to 6 percent. Additionally, studies have shown that 80 percent of pedestrians struck by a car going 40 mph will suffer a fatality, while at 30 mph, the likelihood of death is reduced to 40 percent. At 20 mph, that figure drops to just 5 percent, illustrating the importance vehicle speed plays in pedestrian safety. The likelihood of a pedestrian collision occurring at lower speeds is also reduced due to shorter braking distances. Rather than addressing Lexington’s roadways after the fact, designs should be initiated at the development and planning phase to create the appropriate street width to restrict vehicle speed.