According to a report from talkofthetown.com, a low-speed traffic circle, or “roundabout,” is slated to be installed at the end of Jackson Street Extension in Alexandria. The intersection links Jackson Street Extension with Twin Bridges Road, Lodi Road, and Horseshoe Drive. The initial plan called for a four-way stop sign, but Nick Verret, District 8 engineer-administrator with the Louisiana Department of Transportation and Development (DOTD), said a roundabout would offer better safety and efficiency than a four-way stop or a traffic light signal.
The debate over the most effective traffic control devices for intersections has been ongoing throughout the last century. As far back as 1934, a study published in the Journal of Social Psychology reported that approximately 25 percent of drivers who approached an intersection with visible cross traffic failed to come to a full stop at the stop sign. Another study revealed that when there was no approaching traffic, only 14 percent of drivers fully stopped their cars. This frightening figure comes from research conducted in 1968 in Berkeley, California, which was published in the Law & Society Review. For a recent discussion of these studies and the efficacy of stop signs generally, see this article from Slate.
Roundabouts on the other hand enjoy a significantly better reputation for safety. A study published in the American Journal of Public Health in 2001 looked at crash statistics for 24 intersections across the U.S. that were converted from stop sign or traffic light signal controls to roundabouts. Traffic accident rates at the intersections dropped dramatically following the conversion, including a 90 percent reduction in the number of crashes involving fatal or incapacitating injuries. Roundabouts also offer improvements to traffic flow. The DOTD’s Verret estimates that the Jackson Street Extension roundabout will result in a “50 percent increase in capacity” for the intersection,” which will help to reduce the long queues that occur during peak times. The trade-off is that roundabouts are typically more expensive to install and maintain than signs or signals. The Jackson Street Extension roundabout will cost $2.34 million, with $1.6 million funded with federal dollars and $740,000 funded by the city of Alexandria.