As the modern roundabout becomes a more popular intersection alternative in the United States, the ability of the roundabout to effectively manage traffic and to do so safely is on the forefront of engineering concerns. Despite decades of international success and credibility, regions throughout the U.S. have been hesitant to implement roundabouts in place of more traditional intersections. This case study of a series of intersections in Dublin, OH assesses the operational performance of roundabouts as it compares to that of their stop-controlled and signalized counterparts and analyzes historical crash data to evaluate the safety of the various intersection types. Operationally, roundabouts proved to operate better than their alternatives up to a certain capacity. While the roundabouts did not show significantly fewer crashes than other intersections, injury rates for crashes were lower at roundabouts. With further data regarding traffic volumes, this research can help U.S. engineers understand the operational and safety benefits of modern roundabouts
