Roundabout Studies in Kansas

The Kansas Department of Transportation (KDOT) became interested in roundabouts in 1998 and started designing and building roundabouts on state highways in Kansas (KS). They sponsored three research projects to get before and after data at several Kansas roundabout locations. These studies are still on going at Kansas State University (KSU). Concurrently, the traffic engineer in the City of Manhattan, (City) when confronted with a high crash rate at the intersection of two residential collector streets with two-way stop control, chose a roundabout over other options. The City cosponsored a project with Mack Blackwell Transportation Center (MBTC) to compare the traffic operations of the roundabout with other options. The Insurance Institute for Highway Safety (IIHS) funded an additional project to get before and after data and analyze operation of roundabouts in Hartford County, MD, Hutchinson, KS and Reno, NV. The paper will review the data collection and analysis techniques and present results of several comparisons of roundabouts to other types of traffic control that show that the roundabout is superior to almost every other type of traffic control based on the (MOEs) used. The authors will present the results of their analysis that lead them to conclude that roundabouts are the safest and most effective type of intersection traffic control available today. The paper will also present a brief review of some, irrational public opposition. 1. THE MANHATTAN ROUNDABOUT STUDY The material in this section is exerpted from a report the authors wrote for Mack Blackwell National Rural Transportation Center: “Modeling Traffic Flows and Conflicts at Roundabouts”.(Russell, et al, 2000) The full report is available on the Mack Blackwell web site. Figure 1. Omnidirectional Video Camera Mounted to Street Light Pole 4 Conférence spécialisée en génie des transports de la Société canadienne de génie civil 4 Transportation Specialty Conference of the Canadian Society for Civil Engineering Montréal, Québec, Canada 5-8 juin 2002 / June 5-8, 2002