They are around (slowly!) eating the suburbs ( News Washington )

Hillsboro, Va., recently added detours on both sides of town to improve the flow of commuters heading from West Virginia to DC.
Hillsboro, Va., recently added detours on both sides of town to improve the flow of commuters heading from West Virginia to DC (Michael S. Williamson/The Washington Post)


A quiet round of revolution is sweeping America’s suburbs. And it can continue unbounded and unsigned, except for Lee Rodgerdts.

It turns out that the best nations in the US Bureau of Transportation Statistics do not track the nation’s roundabouts, roundabouts or traffic circles. I did not bow to him. But that heavy responsibility fell on the shoulders of the late Rodegerdts in the quarter century, an engineer and talented amateur photographer and musician in Portland, Ore.

In the late 1990s, the Federal Highway Administration Rodgerdts composed a modest but stealthily cheerful plan to write a book about the turnstiles. The issue is “Ringabouts: An Informational Guide.” In the course of his research, Rodegerdts was surprised to discover that none of the new intersections were holding mushrooms across the country.

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So he began to count. And he counted through another edition of the guide, through dozens of interviews and conversations, through research projects and through endless research projects. Earl soon migrated online, where he still spent his time combing through submissions from a small army of amateur enthusiasts around him, examining new twists and turns and using published rumors and historic satellite photography to date their manufacture.

When Rodegerdts started, he counted about three hundred national tours. As of 25 years later, it counts about 9,000. And that doesn’t include 160-plus roundabouts or 700-plus circles of traffic (which is very different from roundabouts).

Compared to the hundreds of thousands of sections peppered with the normal American landscape, controlled by stop signs and traffic lights, the surrounding animals are rare. But, unlike the rulers, they frequently confound and lie down, and fast all around.

People doubted that we could hold on,” Rodegerdts told us. “But I think we have as much.”

Today’s roundabout is based on a geometric design that enforces traffic, a slow and simple innovation born in Britain in the 1960s: as a rule, people already have the right to go in a roundabout. In organized roundabouts and traffic circles, which are still hidden in many East Coast cities, traffic moves faster and vehicles already in the circle often have to yield to newcomers.

In the United States, the first circuits were often built in major cities. In general, our analysis shows, they are most likely to be built in well-educated and tax-rich towns. These days, the fastest growth is in the suburbs and villages.

“It’s difficult to fit a roundabout into our dense urban environment,” says Rodegerdts. “So many intersections are either going into new parts or retrofits of existing ones, often suburban or rural intersections.”

what’s going on, you ask? Because the circuits offer impressive safety gains. In general, patrols will reduce fatal crashes by 90 percent and cut all vehicle injuries by at least 75 percent, even when adjusting for the higher volume of cars.

In a rural two-way stop, the gain can be even more dramatic. The circuit can detect nearly 90 percent of all traffic injuries, both fatal and nonfatal. After all, it’s hardly possible to blow through a circuit at 60 miles an hour, and T-bone a minivan — all too common at typical rural intersections.

“This is the beauty of the circuit,” Rodegerdts told us. “It’s geometry. It is the work of the curves. And don’t rely on a marketing strategy to be the only thing stopping you from hitting the top speed.

So what is the status quo? Florida boasts the largest population, but it also has the third largest population in the nation. Nebraska has its fair share of hikers, but they are spread over one of the most sparse (and often the most scenic) road networks in the country. By a mile, Maryland is emerging as the all-around champion.

But there are almost no states that are trivially easy. Cut to almost any date, the Indianapolis suburb of Carmel is as exclusive as the nation’s surrounding capital. And, as in Rodegerdt’s data, Carmel’s network of roundabouts is largely the work of one man’s visionary — in this case, seven-term Republican mayor and legendary cornerback Jim Brainard.

A lawyer by training, Brainard’s experience on the rounds since he started on the job in 1996 is clear that he has seen many in the United States. But those intersections have moved to newer ones, and since the city was demanding a safer and more walkable city, he thought he had a solution.

After all, vanishing circles were rare in the United States at the time. As one of the highest-income, most educated cities in the country, Carmel was fertile ground for commercial innovation. However, it took some effort and a weekend research trip to Purdue University to convince the city’s architect, who was skeptical. (Several hundred intersections later, Brainard said, there was one time incredulously asking the leader in a roundabout way and the commander in a roundabout way).

The surrounding cities and counties moved cautiously, but Brainard was carefully constructed by sheer force of will and some public debt.

Brainard’s idea is that if Paris can build a world-class, wrap-around urban area on a flat, unsightly but fertile site, then Carmel (pronounced CAR-MULL) can. He is anxious but bold, describing his goals in epochal terms, referring to European empires and monarchs, while explaining the need to build infrastructure to last for the next thousand years.

A monarch is almost a suitable description for Brainard in this place. Carmel became a city in 1976, as White Flight and other suburbs began to swell. Brainard has already served longer than all other mayors in state history combined (fun fact borrowed from Indianapolis Star columnist James Briggs). During that time, Brainard saw the city grow from 38,000 residents to more than 100,000.

As a major, more than a hundred patrols have been built, the carnage traffic is so shocking that the local fire department rarely uses its jaws of life-extracting equipment anymore. But the twists and turns are just one pillar in Brainard’s larger plan to build a dense, European-style city in central Indiana. To this end he also added winding, leafy paths and a glittering concert hall that hosts everything from Carmel Symphony Orchestra performances to Michael Bolton’s special holiday.

Why does the Midwest love orchestras so much?

Around the linchpin in Brainard’s walkable downtown vision. Not only that because they are often more pedestrian-friendly, but also because they can reduce pollution and allow designers to fit more traffic into a smaller space. On its key north-south stretch, Carmel replaced five lanes of traffic with only two lanes and multiple roundabouts. Green space and sidewalks have grown where streets used to be, and overall traffic on the road has increased.

In all of Carmel, as many as nine regular traffic signals remain, Brainard said. And during the term of his office the following year the city will be left on the track to have only one. Ironically, as a nearby billboard notes, it is the site of one of the first automatic traffic lights in the United States. And now in Carmel, at least, it will be the last.

“It’s in the middle of a small town that’s always been there, and it’s being built on all four corners, so it’s just going to stay,” Brainard said, explaining that there’s no room for a roundabout at that point.

But it is quite safe, the mayor informed us. “You can’t drive it fast across the field.”

Why? Because, he says, “we have placed a circuit on both sides.”

Hello! The Department of Data would be nothing without your driven questions! We want to know what you are curious about. What are the worst streaming cities? Which countries export the most human hair? How many jobs did the Paycheck Protection Program deal with? to save? Just ask!

To get every question, answer and factoid in your inbox as soon as we publish it, Check it out here. If you are looking for an inspiring column, we will send you an official Department of Data button and ID card. This week, one button goes to our colleague Shira Ovide, who will be your friend if you sign up for her new newsletter. Shira’s questions about revolving doors got us thinking about other circular things that are much more sinister, which are actually just more effective. Another boss goes to Rob DeRocker, a New York public relations professional who represents Carmel and who last year published the most powerful six words in the English language: “We’re doing a story about turns.”


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