The joy of roundabouts might draw the comment that you should probably think about “getting a life!” if you derive joy from so mundane a traffic function. However, they do considerably improve traffic flow and reduce accidents compared with regular traffic intersections. So, we should feel a little less concerned if we draw joy from them.
Much to my surprise when I started investigating the topic for this blog, the origins of the traffic roundabout appear to be the design of Pierre L’Enfant for Dupont Circle in Washington DC in the 1790s. However, the idea didn’t catch on too well in the U.S. They seemed to prefer stop signs and traffic lights.
The first modern roundabout was built in northern England in 1907. This, if you think about it, was obviously driven by the advent of the motor car. Horses didn’t really need that much traffic control except, maybe in the centers of large cities.
The UK was the first country to standardize roundabouts and how they operate. The US version came with the regulation that vehicles on the roundabout had to give way to those entering the roundabout. If you think about it, that’s a predictable log jam once any sort of volume uses the roundabout. Waiting to enter the roundabout creates far less congestion than waiting on the roundabout. The UK found that this simple design, together with the “yield” regulation, created a 10% increase in throughput and a 40% reduction in accidents on intersections. As one expert noted, in a 4-way stop situation, you have to worry about vehicles that could hit you coming from three different directions whereas, on a roundabout, you only have to worry about one vehicle from one direction.
There are other advantages as well. Roundabouts eliminate the possibilities of head-on collisions and T-Bone collisions. They eliminate the costs of purchase, installation and maintenance of traffic lights. They also permit the execution of U-Turns without endangering anyone. Altogether, a far better concept provided the driving public is disciplined enough to follow the “yield” concept.
After the UK standardization exercise in 1966, countries seemed to fall over themselves to build roundabouts. By 1990, France was building 1,000 roundabouts a year. The Netherlands, in the 1980s alone, build 400 roundabouts in six years. Again, to my surprise, and because most Americans I have met have little idea of what a roundabout is, apart from the fact that they don’t seem to like them, by 2014, the US boasted 10,341 roundabouts. But, then, it’s a big country.
This blog was prompted by an article in the Economist about the development of the town of Carmel, Indiana. One politician, Jim Brainard, decided in 1995, when he was running for mayor, to study urban planning. He walked around a large number of his future neighborhoods and asked questions. He discovered that people wanted things closer. They didn’t want to drive for miles for a pint of milk. They wanted to walk and wanted to see their neighbors. Large, single-family, lots virtually eliminated that possibility, so he decided, virtually single-handedly, to change his city. Underground parking, high-rise buildings and roundabouts, among other ideas meant less miles of road, and more compact communities that could receive better and more efficient services.
Roundabouts have allowed Carmel to grow without needing to widen roads. In a few places, they have even allowed them to be narrowed. The city’s road death-rate is one fifth of the national average and roundabouts have allowed the city to shrink the main thoroughfare through the center from five lanes to two lanes.
The city now has 145 roundabouts. Mt Brainard has stated that “sprawl kills cities” and roundabouts have helped him prove that to be true.
We should definitely celebrate the lowly roundabout and get rid of the menace and costs of Stop Signs and Traffic Lights where they are not at all necessary.