In Defense of Traffic Circles
I have been reading up on traffic circles, and have come to the conclusion that they are pretty good idea. The ones I use most often in Chico are along West 8th Avenue. It has been recommended that the city add more in the upcoming decades. Here is why I think they should:
1) Studies show changing 4-way stops to traffic circles improves safety. A 2001 study of 23 intersections in the United States reported that converting intersections from traffic signals or stop signs to roundabouts reduced injury crashes by 80 percent and all crashes by 40 percent. Similar results have been reported in Europe and Australia.
2) Traffic circles reduce vehicle emissions and fuel consumption. Why? Because the traffic is kept moving, and is not required to come to a full stop (except to yield). Much of our fuel use and car exhaust comes as a result of idling (0 mpg) and then accelerating from a full stop. In one study, replacing a signalized intersection with a roundabout reduced carbon monoxide emissions by 29 percent and nitrous oxide emissions by 21 percent. In another study, replacing traffic signals and stop signs with roundabouts reduced carbon monoxide emissions by 32 percent, nitrous oxide emissions by 34 percent, carbon dioxide emissions by 37 percent, and hydrocarbon emissions by 42 percent. Constructing roundabouts in place of traffic signals can reduce fuel consumption by about 30 percent.
3) Traffic circles can be landscaped to look pretty. It is nice to see a small island of green in the middle of an intersection, a big improvement over a patch of asphalt.
You can read more about traffic circles and roundabouts from the Insurance Institute of Highway Safety.