Many developments have taken place since publication of the FHWA’s Roundabouts: An Informational Guide in 2000. Ongoing research (particularly NCHRP Project 3-65, Applying Roundabouts in the United States) will enhance guidelines on operational analysis, design characteristics, and safety analysis of roundabouts. Considering that the Guide has become an authoritative national publication, it would be of great benefit to update this Guide after critically reviewing available information. Furthermore, incorporating new research on non-motorized users will contribute significantly to improving roundabout applications for pedestrians, bicyclists, and users with special needs (visual and other physical impairments).
Some of the areas where revisions might be considered are geometric design (including triple-lane roundabouts); intersection sight distance; speed estimations; lane markings, signing, and other traffic control devices; construction and maintenance; safer accommodations of pedestrians; safety evaluation; access management considerations; applications at ramp terminals or interchanges; and mini-roundabouts.
Source: NCHRP Report 672: Roundabouts: An Informational Guide
Published: 2010
