TRB sponsored the 5th International Conference on Roundabouts which took place on May 8-10, 2017, in Green Bay, Wisconsin. The conference focused on research, design, operation, safety, evaluation, and practical experience with the increasingly used roundabout form of an intersection. Visit the proceedings website to view the presentations, final program.
TRB's National Cooperative Highway Research Program (NCHRP) Synthesis 488: Roundabout Practices summarizes roundabout policies, guidance, and practices within state departments of transportation (DOTs) as of 2015. The synthesis may be used as a reference for state agencies that are creating or updating their roundabout and intersection control policies.
Project: Project Information
Well-designed Modern Roundabouts enhance the achievement of Access Management principles
Maintain Integrity of Arterials
Balance Mobility and Access
Extend the life of
Roundabout Operational & Safety Characteristics:
Driveway and intersection spacing versatility
Geometric flexibility (properly designed)
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.