Why Roundabouts?

Roundabouts are designed to improve safety for all users, including pedestrians and bicyclists. The Federal Highway Administration Office of Safety identified roundabouts as a proven safety countermeasure because of their ability to substantially reduce the types of crashes that result in injury and loss of life. Most significantly reducing the types of crashes where people are seriously hurt or killed by 78-82% when compared to conventional stop-controlled and signalized intersections, per the AASHTO Highway Safety Manual.

Click on each graphic to view or print.

Roundabouts are a significantly safer type of intersection creating lower traffic speeds and fewer points of vehicle conflict. The diagram below illustrates the difference in conflict points between a conventional intersection and an equivalent single-lane roundabout. There are 32 conflict points in the conventional intersection (8 merging, 8 diverging, 16 crossing) and only eight total conflict points in an equivalent roundabout (4 merging, 4 diverging). Additionally, the type of conflicts in a roundabout are of the same-direction variety, which result in substantially less severe collisions with a lower likelihood of injury or death.

Studies have found roundabouts reduce vehicle emissions and fuel consumption by 30% or more. This is due to the reduction in idle time by vehicles waiting for the light to change.

Pedestrian-versus-vehicle conflict points are also significantly fewer in a roundabout (as shown in the below diagram) with only eight as opposed to 16 at a conventional intersection.

Roundabout Tips to Remember

  • Take it slow. Roundabouts are intentionally designed to slow vehicle speeds to 15-20 mph.
  • Look left and yield to all pedestrians and vehicles already inside the roundabout.
  • Stay in your lane. Do not change lanes within the roundabout. As with any other type of intersection, you must be in the proper lane before entering.
  • Keep moving. Once in the roundabout, you have the right-of-way. Always stop for pedestrians.
  • Clear the roundabout for emergency vehicles. Exit the roundabout, then pull to the right. Do not stop within the roundabout.

The Ohio Department of Transportation Videos

View the Ohio Department of Transportations’s roundabout rules videos, with the three levels of movement on roundabouts .