You're driving through Austin and come to an intersection with something unfamiliar in the middle. No stop sign. No traffic light. Just a giant concrete circle. Do you yield? Gun it? If you've wondered this, you're not alone.
More of Austin's intersections are being turned into roundabouts as part of a safety strategy. In theory, vehicles keep moving, if everyone knows what to do. (Hint: drivers must yield to traffic already in the circle. And yes, that includes cyclists or pedestrians in crosswalks.)
The city has built 47 roundabouts. The most recent one popped up in April at Pleasant Valley Road and Terri Road.
Construction is getting underway this month on roundabout number 48 at Evergreen Avenue and West Mary Street. The city's 49th roundabout is coming next year to Bluebonnet Lane at Del Curto Road. What could become the 50th is being designed for the intersection of Rutland Drive at Parkfield Drive.
Austin's growing embrace of roundabouts is part of a broader effort to reduce crashes, especially the most dangerous ones. Government engineers and transportation researchers say roundabouts reduce right-angle crashes — also known as T-bones — and eliminate head-on collisions entirely.
"The reduction in crashes is significant," said Ruth Steiner, a professor of urban and regional planning at the University of Florida. "Often, the reduction in severity is even more important, because ... you have slower traffic."
Traditional four-way intersections can have up to 32 points where cars cross paths. Roundabouts cut the number of these conflict points by 75%. They can benefit pedestrians, too, because drivers are forced to slow down.
But roundabouts can bewilder drivers who don't realize they're supposed to yield to those already in the traffic circle. That confusion can make it even more dangerous for cyclists. Some roundabouts are harder to cross for the visually impaired.
"One of the groups that's been concerned about safety around roundabouts has been blind pedestrians," Steiner said. "They depend upon hearing traffic stopping at an intersection. And in a roundabout, it never stops."
Roundabouts don't come cheap. The city dedicated $1,316,655 to design and build the roundabout at West Mary and Evergreen Avenue, according to a city bond document. The money is coming from a $720 million mobility bond approved by voters in 2016.
Installing a traffic signal, by comparison, typically costs about $500,000 in Austin. But they don't provide the same safety benefits or allow drivers to keep moving. Unlike traffic signals, roundabouts work without electricity.
Austin's flirtation with roundabouts goes back at least to 1999, with a few "traffic calming circles" installed in Hyde Park. But it wasn't until a roundabout evangelist rolled into town that things really got moving.
"When I came to Austin in April of 2010, along with having the interest in roundabouts, I was also on an international roundabout committee," said Gary Schatz, a former city traffic engineer who now runs his own consulting firm in Katy. "I kept seeing different intersections in Austin and thought, 'That kind of wants to be a roundabout.'"
At the time, Austin's circular intersections weren't designed to modern standards. Schatz said they often lacked features like small "splitter" traffic islands that route vehicles into the roundabout. So he started with working developers and other departments to change that.
"We knew that properly planned and implemented roundabouts were safer, more efficient, better served all roadway users and made great community gateways or focal points," he said.
Some of the first roundabouts Schatz helped bring about were at Todd Lane and St. Elmo Road and Davis Lane at Leo Street.
There was resistance. Schatz recalls one real estate developer took "an absolute beating" from city staff and even from his own company for including roundabouts in the design of a residential neighborhood.
"We fear the unknown or the unfamiliar," he said. "Oh my God, what if I screw this up? What if I get in there and I go the wrong way or I do the wrong thing? What if somebody runs into me?"
But Schatz says those internal fights helped shift the culture. The city's traffic engineering staff has come to embrace traffic circles.
"Basically around 2013 or '14 is when we started really pushing for roundabouts a little more," said Mario Porras, a supervising engineer at the city.
His colleague in the transportation department, Cody Stone, said the team started identifying problem intersections where people were getting hurt.
"Roundabouts show about an 80% reduction in fatal and injury crashes" compared to an intersection with stop signs or traffic signals, Stone said. "We're trying to speed them up."
The city still faces resistance, especially when roundabout design requires slicing off corners from private property. With bond dollars dwindling, only so many roundabouts can be built. But city engineers say support is growing as drivers get used to the design.
"We've gotten a lot of support for roundabouts, not only because of the safety benefits, ... but also some of them provide reduced congestion or less delay," said Stone. "We do hear from some residents where they'll reach out saying, 'Have you all looked at a roundabout here? I think it would be great.'"
