MY SCOUT TROOP once spent a day counting cars at intersections in our old town center, so the traffic lights could be correctly timed for the volume going in each direction. And I guess I’ve had a keen appreciation for the traffic planner’s job ever since.
In the little beach town where I live now, which is subject to very heavy weekend and summertime tourist traffic, it’s often easy to catch a red light every half-mile or less, turning a five mile cross-town distance in 20 minutes or more of stop-and-go aggravation. This naturally encourages speeding by the locals who’ve seen all the sights before, mounting frustration with dawdlers, and occasional attempts to beat the yellows—not good for safety. And, of course, none of the lights are “smart” enough to know when there are no drivers waiting at one or more directions, so we all wait while the light goes through its preprogrammed sequence, clearly timed for heavy traffic flow, oblivious to reality.
Worse, the downtown light that controls the heaviest traffic will regularly lose its synchronization with another light just a block away, so that block fills with cars, the intersection jams up and the resulting backup can extend down the canyon for nearly a mile. Too bad the CalTrans officials responsible can’t hear the resulting shouting and honking, but I now have their names and phone numbers (call your city officials). Tip: After weeks of repeated pleas for help, saying you’re going to call the Mayor if they don’t fix it immediately got a same-day response.
I’m sure we each have personal examples of traffic light headaches, like sensors that can’t recognize a motorcycle, greens that only last for seconds, etc., but consider that a superior alternative to “dumb” traffic lights already exists—roundabouts.
First, a word about what is and what isn’t a roundabout. Although much larger “rotaries” and “traffic circles” (think Paris’ Place L’Etoile, around the Arc de Triomphe, Thomas Circle in Washington, D.C., or Columbus Circle in Central Park) have been built since 1877, the “modern roundabout,” as the DOT defines it, was designed by Frank Blackmore of the UK’s Transportation Research Laboratory in the 1960s. Distinguished by its much smaller size and radial entry roads, these mini roundabouts require traffic to slow to 15–25 mph, circle counter-clockwise (in countries where people drive on the right), and give priority to vehicles already in the roundabout, in contrast to traffic circles, where traffic enters at high speed on a tangent to a large circle, changing lanes to exit, which can be very chaotic. In fact, accident statistics show that large traffic circles are not particularly safe, and the UK-style mini roundabout has become the favored design worldwide. The town of Summerlin, Nevada, built the first one in America in 1990, but they have quickly proliferated across the country.
Consider the advantages: The basic roundabout controls traffic without requiring vehicles to come to a stop. Remember, a car idling at a light is getting exactly zero mpg, making heat and smog, and while stopping completely uses more brake pad material, acceleration from a stop requires more fuel than simply slowing. As a result, studies show that pollution is greatly reduced: CO by 15–45%, CO2 by 23–37%, NOx by 21–44%, and hydrocarbons by as much as 42%. And because roundabouts don’t create unnecessary delays, studies show they improve fuel consumption by 23–34%, while speeding traffic flow by 13–89%. Is there a less painful or less expensive way to reduce our collective “carbon footprint?”
And if those statistics aren’t impressive enough, consider that roundabouts have an even greater benefit on safety. Every MCN reader knows how dangerous traditional intersections can be and how left turns across a rider’s path create the most serious accidents. Imagine a light-controlled intersection with just a single lane in each direction: With left turns, right turns and straight ahead traffic possible in each direction, there are 32 potential contact points, many of which are head-ons and T-bones at high speed. By comparison, the roundabout has only eight, and most accidents are side-impacts at shallow angles. A U.S. statistical sample shows that roundabouts generate 39% fewer collisions, 76% fewer injuries, and 90% fewer serious injuries and fatalities than traditional junctions.
Plus, there are additional benefits: U-turns are easily accomplished, roundabouts are quieter in operation as the need for heavy acceleration is reduced, they can be cheaper to build and maintain than a traffic light-controlled intersection, and they don’t need any more space to construct (multi-lane roundabouts are typically less than 250 ft. in diameter).
Pedestrians are also safer. Crosswalks are usually placed at least one car-length outside the circle, to reduce slowing inside the circle, and pedestrian islands positioned between the inbound and outbound lanes add visual clues for drivers as well as provide a safe place for pedestrians to stop mid-crossing, so they only need to keep an eye on traffic in one direction.
There are two other effects that get my personal approval, although you can’t find statistics on them. One is that roundabouts don’t force traffic to stop and line-up, so that if you happen to be at the back of the pack, your progress is not determined by the driver ahead with the slowest reaction times or most distractions. This bunching effect makes traffic much more dangerous as well, as everyone is more vulnerable to the mistakes of a single driver, and accordion-type impacts that can catch trailing drivers unaware are common. By comparison, roundabouts allow traffic to spread out, and every motorcyclist knows they are safer when they have space around them to maneuver, rather than play the potential meat in a metal sandwich. Although California motorcyclists can take advantage of lane-sharing, slipping to the front of the line at lights to gain this advantage, everywhere else, riders don’t have this option and are at the mercy of surrounding drivers.
Lastly, roundabouts are fun on a motorcycle. The brief slowing, quick flicks of the steering and burst of acceleration make negotiating a roundabout even faster and easier on a bike than it is in a car, and isn’t that what riding is all about?
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