FAQs

What is a roundabout?

A roundabout is a one-way circular intersection engineered to reduce congestion and maximize safety. The “yield at entry” rule reduces delay by eliminating unnecessary stopping. Vehicles yield to traffic in the roundabout and enter only when there is a safe gap in traffic. Modern roundabouts have design features that improve traffic flow and reduce delay, fuel consumption, and air pollution. That’s why roundabouts are often a better solution at sites where we typically see traffic signal lights or stop signs.

Are roundabouts safe?

Yes. Roundabouts can carry more traffic than a traffic signal, but with one fourth as many injuries, and one tenth as many fatalities. This is because vehicles in a roundabout are moving slowly, in the same direction. So, instead of head-on and broadside crashes, crashes that do occur are mostly lowspeed side swipes. Injuries are rare. That is why roundabouts are important  Each year, about 7,500 Americans are killed at intersections and many more are injured or disabled. Roundabouts can save lives.

Aren't traffic signals safer for pedestrians?

No. Pedestrians are safer at roundabouts because a roundabout crosswalk is split into two shorter crossings of low-speed, one-way traffic. At traffic lights, pedestrians can spend more than twice as much time in the road and they need to look in four different directions: for traffic turning right or left on green, or right on red, or running the red light. With roundabouts, traffic is slower and crosswalks are shorter. Roundabouts have about one fourth as many pedestrian
injuries as a typical “crossroad” type intersection.

Why are so many communities building roundabouts?

Roundabouts are an economical way to solve serious safety and congestion problems. They can reduce congestion without the high cost of adding a signal and widening the entire roadway. Roundabouts reduce fuel consumption and air and noise pollution, and many people think landscaped roundabouts are
more attractive than signals.

Are roundabouts safe near schools?

More than 50 roundabouts have been built near schools in the U.S. Speeding is reduced in the school zone and safety reports are favorable.

Some roundabouts look awfully tight for trucks.  Will trucks fit?

Yes. Roundabouts are designed for trucks. Trucks proceed slowly and sometimes use the paved “truck apron” around the central island. As at other intersections, trucks make wide turns; therefore, other drivers should give them plenty of space.

How about bicycles in a roundabout?

Depending on their experience riding in traffic, cyclists can circulate as a vehicle or use the sidewalk as a pedestrian. As always, make sure drivers see you.

Are roundabouts suitable everywhere?

No. The selection of a roundabout, traffic light, or stop sign is complicated and depends entirely on the situation. Expert traffic analysis can determine whether a roundabout, traffic signal light, or two- or all-way stop is the most-effective solution.