Access Management Near Modern Roundabouts: State of the Practice

Modern roundabouts have been shown to be a safe and efficient alternative to more traditional roadway intersection designs. They are much more efficient than signalized intersections in many situations in that traffic is allowed to remain in motion albeit at a slower speed. Safety is often improved since traffic speed through the roundabout is reduced and the most serious types of conflicts are reduced or eliminated. Like traditional intersections, the safety and operational efficiency of roundabouts can be compromised by inappropriate access to nearby land and land development, especially development that generates a large number of trips. A particular concern near roundabouts is the location, spacing, and configuration of driveways. However, other access management features and practices may also be of concern near modern roundabouts. These considerations may include things like alternative access, shared access, and cross access. This synthesis of practice should explore the state of the practice of access management near modern roundabouts. This synthesis will be of particular benefit for the planned update of the TRB Access Management Manual. It should also be of use for practitioners at the state and local level who need to manage land access near new and existing modern roundabouts. Sponsoring Committee: AHB70, Access Management Date Posted: 06/04/2007 Date Modified: 08/29/2007 Index Terms: Access control (Transportation), Roundabouts, Roundabout design, State of the practice, State departments of transportation, Intersections, Traffic circles, Highway safety, Highway design, Cosponsoring Committees: Subjects Highways Design Operations and Traffic Management Planning and Forecasting Safety and Human Factors