We are continuing our discussion of South Carolina's growing reliance on roundabouts in road construction. Roundabouts are a safer alternative to a stop sign or traffic light intersection. They are smaller than the old traffic circles, and they have proven successful in reducing the number of car accidents, especially accidents with injuries.

The design improves safety by eliminating the possibility of the most dangerous accidents at traditional intersections: right-angle, left-turn and head-on collisions. At intersections, too, there are more accidents with injuries because drivers tend to go faster -- running a "pink" light or ignoring a stop sign can turn from a fender bender into a catastrophic crash with just the slightest increase in speed.

According to the Insurance Institute for Highway Safety, intersections converted to roundabouts see a 40 percent reduction in crashes and an 80 percent reduction in crashes with injuries. For merchants located near a busy intersection in Mount Pleasant, the planned installation of a roundabout would be welcome: "Hardly a day goes by that there's not a wreck out there somewhere," said one business owner.

Roundabouts can be more expensive than traffic lights -- they run from a modest $50,000 to as much as $400,000, while a signal costs $150,000 or so -- and that can be daunting to city planners. Roundabouts, though, offer a community a unique beautification opportunity. Cities usually landscape the centers of the roundabouts or use them as homes for monuments.

With more and more cars on the road these days, and more and more distractions for drivers, the risk of being involved in an accident has increased. In 2009, the IIHS reports, red light running claimed 676 lives in the U.S. About 113,000 people were injured, and the majority of them were not the drivers running the light; rather, they were passengers in those drivers' cars, occupants of other vehicles, pedestrians and bicyclists.

Communities in the Lowcountry and throughout South Carolina are giving the roundabouts a whirl. The savings in both human and property terms can more than compensate for the investment.

Source: Post & Courier, "Mount Pleasant's traffic loops help prevent accidents, gridlock," Prentiss Findlay, Nov. 28, 2011