Roundabouts are becoming more popular in Arizona as the state tries to figure out how to reduce traffic fatalities on our city streets.
What is a Roundabout?
According to the Arizona Department of Transportation ("ADOT"), a roundabout is a one-way circular intersection without traffic signal equipment in which traffic flows around a center island. The modern roundabout functions with yield control at the entry points, and gives priority to vehicles within the roundabout.
Is a Roundabout the Same as a Rotary or a Traffic Circle?
No. Modern roundabouts have a smaller diameter than most traffic circles, resulting in safer conditions and lower speeds. Vehicles can enter modern roundabouts much easier than traffic circles due to flared approaches, entry angles, slower speeds on the circulating roadway and the fact that vehicles entering roundabouts always yield to circulating traffic. Some larger traffic circles are downright scary! They are large in diameter, often have many lanes, have high circulating speeds and can require some merging and weaving between lanes to exit.
Why Not Install a Traffic Signal?
Roundabouts keep traffic moving through an intersection, so the potential for crashes in the center are diminished. Drivers move at a slower speed, usually 25 mph. According to ADOT, modern roundabouts reduce accidents by 40% to 60%, reduce injury accidents by 80% and fatal accidents by as much as 90%. In addition, eliminating a traffic signal saves the city money on installations, maintenance, and electricity.
Don't Like Roundabouts?
They take a bit of getting used to, but don't assume they are bad or don't work because you have experience driving near Prospect Park in Brooklyn, or Dupont Circle in Washington D.C. Modern roundabouts are slower, easier to maneuver, less complicated, and also prettier than all those ugly traffic lights!