Roundabouts in the United States Module 3 Safety

Roundabouts in the United States Module 3 Safety Considerations Safety benefits of roundabouts Research has shown there are many safety benefits associated with roundabout intersection design.

Safety is a major consideration on our highways and roadways PHOTOGRAPHY SOURCE: Fred Ranck In the year 2003 there were an average of 6, 850 motor vehicle crashes per day at intersections in the United States. For transportation professionals, safety is a major concern. Roundabouts in the United States Module 3—Safety Considerations

Intersections are the scene of many accidents. PHOTOGRAPHY SOURCE: Fred Ranck Transportation professionals are always looking for ways to reduce the number and severity of crashes. Roundabouts in the United States Module 3—Safety Considerations

What is the effect on crash rates after an intersection is converted to a roundabout? Conventional 4 -way Intersection Roundabout Data from 55 intersections with at least 2 years of crash data before and after conversion of the intersection to a roundabout. Roundabouts in the United States Module 3—Safety Considerations

What is the effect on severe injury rates after an intersection is converted to a roundabout? Conventional 4 -way Intersection Roundabout Data from 55 intersections with at least 2 years of crash data before and after conversion of the intersection to a roundabout. Roundabouts in the United States Module 3—Safety Considerations

How do typical types of crashes compare between conventional intersections and roundabouts? Urban Signalized Intersection Roundabouts in the United States Roundabout Module 3—Safety Considerations

How do typical types of crashes compare between conventional intersections and roundabouts? Suburban Signalized Intersection Roundabouts in the United States Roundabout Module 3—Safety Considerations

How do typical types of crashes compare between conventional intersections and roundabouts? AWSC intersection Roundabouts in the United States Roundabout Module 3—Safety Considerations

How do typical types of crashes compare between conventional intersections and roundabouts? Rural TWSC intersection Roundabouts in the United States Roundabout Module 3—Safety Considerations

How do typical types of crashes compare between conventional intersections and roundabouts? Suburban TWSC intersection Roundabouts in the United States Roundabout Module 3—Safety Considerations

How do typical types of crashes compare between conventional intersections and roundabouts? Urban TWSC intersection Roundabouts in the United States Roundabout Module 3—Safety Considerations

Typical types of crashes at roundabouts Entering Roundabouts in the United States Module 3—Safety Considerations

Typical types of crashes at roundabouts Exiting Roundabouts in the United States Module 3—Safety Considerations

Typical types of crashes at roundabouts Examples of Loss of Vehicle Control Roundabouts in the United States Module 3—Safety Considerations

Typical types of crashes at roundabouts Roundabouts in the United States Module 3—Safety Considerations

Bicycle and Pedestrian Considerations PHOTOGRAPHY SOURCE: Lee Rodegerdts Intersections also introduce concerns for transportation professionals on the safest way to accommodate pedestrians and cyclists. Roundabouts in the United States Module 3—Safety Considerations

Pedestrian Considerations at Roundabouts PHOTOGRAPHY SOURCE: Lee Rodegerdts Data on pedestrian/motor vehicle crashes is very limited. Roundabouts in the United States Module 3—Safety Considerations

How do typical types of pedestrian/motor vehicle crashes compare between conventional intersections and roundabouts? PHOTOGRAPHY SOURCE: Lee Rodegerdts Motor vehicles conflict with pedestrians in the crosswalk areas and can occur as the vehicles enter or leave the intersection from several different directions. A roundabout allows a pedestrian to observe motor vehicles from one direction at a time as they cross the travel lanes. Roundabouts in the United States Module 3—Safety Considerations

PHOTOGRAPHY SOURCE: Lee Rodegerdts Pedestrian Considerations at Roundabouts “Personally, I love them, . . . you only have to stop one lane of traffic, then go to the middle and wait. The cars can’t go much faster than 20 mph through the roundabout so the crossing aspect is great” From the Howard-Suamico—Denise Haltom, School Crossing Guard, Suamico, Wisconsin Roundabouts in the United States Module 3—Safety Considerations

PHOTOGRAPHY SOURCE: Lee Rodegerdts Bicycle Considerations Roundabouts in the United States Module 3—Safety Considerations

Cyclist Movements at Roundabouts – Circulating as a Vehicle. Bike lanes are not recommended within a roundabout. Instead, cyclists merge with traffic before entering the roundabout, circulate with traffic, and then re-enter the bike lane after exiting. Bikes re-enter bike lane Fewer conflict points with motor vehicles Lower motor vehicle speeds (15 -20 mph) Bikes merge with motor vehicles Roundabouts in the United States Module 3—Safety Considerations

Cyclist Movements at Roundabouts – Circulating as a Pedestrian. If a cyclist is uncomfortable riding with traffic, a cyclist can choose to travel instead as a pedestrian. Bikes return to bike lane Bicyclists cross as pedestrians Bikes join shared path with pedestrians Roundabouts in the United States Module 3—Safety Considerations

Summary of the Safety Features of Roundabouts PHOTOGRAPHY SOURCE: Lee Rodegerdts • Travel speeds generally reduced by traffic calming effects • In almost all cases, the total number of crashes is reduced when a conventional intersection is replaced with a roundabout • And more importantly, the number of severe injury crashes is dramatically reduced due to the roundabout’s common direction of travel and similar speeds Roundabouts in the United States Module 3—Safety Considerations