Philadelphia Is Expanding its Network of Roundabouts

Philadelphia is expanding its system of roundabouts, becoming one of a growing number of U.S. cities to introduce the intersection design widely popular in the rest of the world.

As Leo Miranda explains in an article for WHYY, “Traffic safety data and experts say roundabouts are safer and more efficient than traditional intersections. The round shape slows traffic and creates a simpler flow, reducing the chance of serious accidents by eliminating complex turns and merging.” Roundabouts also create smoother traffic flow and increase cars’ fuel efficiency while improving safety. Miranda explains the differences between roundabouts and larger traffic circles or rotaries, which have merging lanes and often have signals or stop signs.

Philadelphia’s newest roundabout, the Penrose Roundabout, will replace a large signalized intersection. “The intersection is included in Philadelphia’s ‘High Injury Network’ of dangerous roads — part of Vision Zero, the city’s effort to target streets with many traffic crashes.”

The wider adoption of roundabouts may just be a matter of time: “A nationwide study found that the longer a roundabout is in place, the more supportive drivers become; around a third of drivers surveyed said they did not like roundabouts, but support jumped to over 50% after roundabouts were installed.”