Operational and Safety Performance of Modern Roundabouts and Other Intersection Types

This project was focused on learning about the safety and operational performance of roundabouts in the United States. Operational and accident data were collected through a nationwide survey. The responses were analyzed for evidence of before-versus-after trends in operational and safety performance and tendencies in design practice. RODEL datasets were prepared from several of the survey responses to create estimates of roundabout performance. A public information brochure was prepared so that the New York State Department of Transportation is better equipped to tell the traveling public about the advantages of using roundabouts where appropriate. The report contains eight chapters and an appendix. Chapter 1 provides an introduction. Chapter 2 describes the survey effort, while Chapter 3 summarizes the survey responses. Chapter 4 shows the results of an operational analysis of the survey responses. Chapter 5 does the same for a broad-brush safety analysis. Chapter 6 presents accident rate models that have been developed based on the survey data. Chapter 7 talks about pedestrian issues. Chapter 8 presents the result of the RODEL analysis. Chapter 8 talks about the informational brochure. Finally, Chapter 9 discusses conclusions, recommendations, and additional work that would be a natural outgrowth of this effort.