FHWA: Making Our Roads Safer One Countermeasure at a Time

https://safety.fhwa.dot.gov/ provencountermeasures. INTERSECTIONS | PROVEN SAFETY COUNTERMEASURES 10. Roundabouts The modern roundabout is a type of circular intersection configuration that safely and eficiently moves trafic through an intersection. Roundabouts feature channelized approaches and a center island that results in lower speeds and fewer conflict points. At roundabouts, entering trafic yields to vehicles already circulating, leading to improved operational performance. Roundabouts provide substantial safety and operational benefits compared to other intersection types, most notably a reduction in severe crashes. Roundabouts can be implemented in both urban and rural areas under a wide range of trafic conditions. They can replace signals, two-way stop controls, and all-way stop controls. Roundabouts are an efective option for managing 82% speed and transitioning trafic from high-speed to low-speed environments, Reduction in severe crashes such as freeway interchange ramp terminals, and rural intersections along high-speed roads. FHWA encourages agencies to consider roundabouts during new construction and reconstruction projects as well as for existing intersections that have been identified as needing safety or operational improvements. Reduction in severe crashes TWO-WAY STOP- CONTROLLEDINTERSECTION TO A ROUNDABOUT Example of a single-lane roundabout. Source: FHWA SIGNALIZED INTERSECTION TO A ROUNDABOUT 78% Example of a multi-lane roundabout. Source: FHWA Source: Highway Safety Manual