June 14, 2023NCHRP Releases the New Guide for Roundabouts

After five years of research and development, we are so excited to see NCHRP Research Report 1043: Guide for Roundabouts published and ready to be implemented on projects. NCHRP Research Report 1043 supersedes NCHRP Report 672: Roundabouts: An Informational Guide—Second Edition, which has been the nation’s go-to guide for the planning and design of roundabouts since 2010.

Why create a new roundabout guide? In short, much has changed in the past 13 years! Since the publication of NCHRP Report 672, a significant amount of roundabout research has been conducted. Our nation has also constructed many roundabouts in that time period (see the Roundabouts Database for the latest counts!), providing practical knowledge that has fueled additional research. NCHRP sought a new guide that would bring together the latest in roundabout research, best practices from the field, and advancements in transportation technology.

To do this, Kittelson & Associates, Inc. reviewed the latest existing planning and design guidance at the state and national level, connected with practitioners across the country to learn from their experiences, and conducted additional research, particularly around serving large trucks and designing for bicycles at roundabouts. The new guide synthesizes what we learned and presents a performance-based approach to the design of roundabouts. It includes guidance for mini-roundabouts and compact roundabouts, pedestrian crossings, traffic control devices, illumination, retrofitting existing roundabouts, and many other aspects of roundabout planning, design, and implementation.

After playing key roles in the development of preceding roundabout guides (FHWA’s Roundabouts: An Informational Guide in 2000 and NCHRP Report 672, Roundabouts: An Informational Guide Second Edition in 2010), it was meaningful for our friends at Kittelson to have the opportunity to lead the development of this latest guide. We have many strong partners to thank, including Sunrise Transportation Strategies, Texas A&M Transportation Institute, Kimley-Horn, and Accessible Design for the Blind.

NCHRP Research Report 1043 is available to be downloaded here on TRB’s website. After years of working hard toward the release of this guide, we’re excited to see it out in the world and hope it proves useful in your next projects! To learn more, contact Julia Knudsen, who managed the guide’s development, or Lee Rodegerdts, who served as a key author and as Principal Investigator for the early stages of the project.