Issue link: http://digital.canadawide.com/i/118157
HotTopics Circle of Life Where safety and traffic roundabouts intersect by Ian MacNeill IMAGINE IF ROAD-SAFETY engineers could wave a magic wand that would not only improve traffic flow at intersections but reduce the number of collisions that occur within them – and, significantly reduce the severity and number of injuries and fatalities resulting from those collisions. Well, as it happens, road engineers don't need a magic wand. They just need to by some drivers – increases driver attention. In other words, motorists pay attention when everyone entering a roundabout shares the responsibility of yielding. What's more, the dangerous practice of running red lights is eliminated when there are no red lights to run. The research shows that pedestrians also benefit from roundabouts, as crossing a roadway means navigating only one direction of traffic at a time, crossing distances are shorter and traffic speeds slower. And drivers in a hurry are pleased to find that, despite slowing traffic down as it moves in a circular direction, roundabouts enhance overall traffic flow efficiency, typically allowing motorists to get where they want to go in less Shanghai, China: vehicle and pedestrian roundabout. time. How much less depends on the situation. But studies indicate that traditional interDYNAMIC DUO sections replaced by roundreplace signal-controlled • IN THE SINGLE-LANE abouts reduce navigation intersections with multi-lane roundabout, drivers yield time of such "intersections" roundabouts. In fact, a 2004 to traffic already in the by as much as 75 per cent. study of 35 intersections concircle, travel counterclockwise until reaching Currently, B.C. has only ducted by the U.S. Departtheir roadway of choice, one- and two-lane roundment of Transportation shows signal, then exit. abouts, but engineers say that when intersections conthree-lane models are feasitrolled by traffic signals are • IN THE TWO-LANE ble, as popularized in Europe. converted into roundabouts, version, drivers intending to turn right enter using Indeed, it was France that piocollision rates drop by 47 per the right lane; those makneered the circular interseccent. Also, studies in Europe ing a left turn enter using tion as early as 1768. And that and Australia show that the left lane. Those headcountry is still home to the "severe accident" rates at coning straight through use world's largest: the six-lane verted intersections decrease either lane, unless signage indicates otherwise. Place de l'Étoile encircling the by as much as 75 per cent. Arc de Triomphe in Paris, These advantages are the result of several design elements. Mainly, where as many as six lanes channel traffic though, the roundabout's circular design entering from no fewer than 12 avenues. All of which explains why B.C. has slows traffic, then channels it in more or less the same direction. The result: collisions bumped up its number of roundabouts, and resulting in injury or death are almost elim- will continue to add more at "new and retroinated, particularly the kind resulting from fitted" intersections. Meanwhile, through drivers turning left across oncoming traffic. driver education, traffic safety experts are In addition, eliminating stop signs – which focused on improving traffic navigation of research shows are seen only as suggestions the roundabouts already in place. istock, (sidebar graphic) B.C. Ministry of Transportation p50-51_HotTopics.indd 51 Coming Soon to an Intersection Near You? ED MISKA, a senior traffic engineer with the Ministry of Transportation, explains why more B.C. drivers are going to see an increasing number of multi-lane roundabouts on provincial roadways. WW Circular intersections have been around for a century. Most were removed in Canada, and now they're making a comeback. Why? EM: There's a substantial difference in the design and operating philosophy of the modern, multi-lane roundabout. In the old days, they were generally larger and the circulating speeds were much higher. Today's roundabouts are smaller. Other design changes have reduced speeds significantly and changed the angle of entry, so that all vehicles are travelling in more or less the same direction — eliminating T-bone and head-on collisions. Now, when drivers do make mistakes, we see low-speed, side-swipe collisions that typically result in little more than property damage. WW Most drivers understand the rules for signal or sign-controlled intersections. Are we in for a big learning curve with multi-lane roundabouts? EM: Less than you'd think. A well-designed roundabout is a like a good computer interface: it just makes sense. Also, there will be sufficient signage so that drivers will know what lane they should be in and what they can or cannot do in terms of entering and exiting. Of course, these roundabouts are still going to be new to some drivers. But there's good info on the Internet about how to use them, and we advise drivers to make use of it. WW An increasing number of jurisdictions are incorporating roundabouts as part of their traffic plans. Is this trend likely to continue? EM: Considering the safety benefits, you're definitely going to see a lot more. WESTWORLD >> S U M M E R 2 0 1 2 51 4/19/12 9:58:43 AM