Create an Account - Increase your productivity, customize your experience, and engage in information you care about.
Show All Answers
A modern roundabout is a circular intersection where drivers travel counterclockwise around a center island. There are no traffic signals or stop signs in a modern roundabout. Drivers yield at entry to traffic in the roundabout, then enter the intersection and exit at their desired street. Studies by the Federal Highway Administration have found that roundabouts can increase traffic capacity by 30 percent to 50 percent compared to traditional intersections.
The Washington State Department of Transportation lists the following reasons roundabouts decrease the likelihood of a collision:
Roundabouts are designed for a travel speed of 15 – 20 miles per hour.
No, statistics show that roundabouts decrease the overall amount of crashes by 40% and reduce injury crashes by 75% at intersections where stop signs or signals were previously used. Pedestrian collisions are also reduced by 40%.
The roundabout will be designed to accommodate delivery trucks, buses, and emergency vehicles. A slightly elevated “truck apron” will be installed in the center to provide an area for larger vehicles to track when necessary.
Entering traffic yields to vehicles in the roundabout, the waiting vehicle enters the roundabout in a counterclockwise direction, and the vehicle exits the roundabout, using their turn signal, at the desired road. All traffic is expected to yield to pedestrians at the designated cross walks.
The Washington State Department of Transportation has some excellent information on roundabouts, including videos. This information can be found on the WSDOT website.
Neighborhood traffic calming circles are much smaller than modern roundabouts and often replace stop signs at four-way intersections. They are typically used in residential neighborhoods to slow traffic speeds and reduce accidents but are typically not designed to accommodate larger vehicles. Many drivers often turn left in front of the circles rather than turning around them.