Roundabout Information

A roundabout is a one-way, circular intersection in which traffic flows around a center island with yield control.All vehicles are required to travel in a counterclockwise direction, to the right of the central island. Roundabouts cause slower speeds which allow drivers more time to react to a situation, and it is generally safer for pedestrians because they only need to cross in the direction of traffic at a time at each approach.Studies on roundabouts have shown the following safety improvements:

  • Improve safety by reducing fatalities, injuries, all crash types, and the severity of a crash if it does occur.
  • Reduces congestion by allowing for more efficient driving with less delays during regular peak driving times.
  • Reduces pollution and fuel use by having fewer stops, accelerations, and less idling time.
  • Saves money because a traffic signal purchase/installation is not generally required, as well as less power and maintenance needed to fix said traffic signal.
  • Improved community quality of life because roundabouts create quieter environments that are both functional and aesthetically pleasing.
  • Roundabouts may not be applicable to all intersections.

Roundabouts are designed specifically to accommodate large vehicles. Truck trailers may drag over the special apron around the central island – it was designed for this purpose.Bicyclists can choose to enter the roundabout and circulate as a vehicle or use the sidewalk around the roundabout.Pedestrians should walk around the perimeter of the roundabout and should not cross the circulatory roadway to the central island. Pedestrians should use the crosswalks on the legs of the roundabout.

How to Navigate a Roundabout:

  • Slow down and yield to traffic already in the roundabout.
  • Look to your left to see if there is an appropriate gap in traffic; if one is not available be prepared to stop.
  • Always enter the roundabout to the right and proceed on the right side of the central island.
  • Maintain slow speeds through the roundabout, generally 15 mph to 25 mph.
  • Do not attempt to pass other vehicles or bicyclists.
  • Yield to pedestrians and bicyclists.
  • Always assume trucks need all available space.
  • When emergency vehicles are approaching with their lights and sirens on, completely clear the roundabout and then pull to the right to allow the emergency vehicles to pass.

Additional Information:

Below is a visual aide comparing traffic between a roundabout (left) and a traditional intersection (right).
Roundabout Intersection Images.jpg
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