Suburban Residential Traffic Calming

In the Washington, D.C./Baltimore, Maryland, suburban areas, postwar residential development frequently featured long curving residential streets with numerous cul-de-sacs. Despite the 25 mph speed limits on the main residential corridors, a more common speed was 38 to 40 mph. This residential speeding led to public outcry, resulting in the development of traffic calming measures. Traffic engineers in the counties surrounding Baltimore and Washington formed the Maryland Traffic Engineers Council to share information on ways to reduce speed in suburban residential communities. This article presents the results of this information sharing, detailing vertical and horizontal alignment measures, such as speed humps (as opposed to bumps), traffic circles, and roundabouts. Other roadway restrictions are described as well.