Chris Doty, P.E.
Assistant City Engineer
Public Works Department
City of Redmond, Oregon
The modern roundabout is an excellent traffic control device. When designed appropriately, the modern roundabout provides the primary need of additional intersection capacity, coupled with many positive features such as improved intersection safety and aesthetics. However, before constructing a modern roundabout in your community, the ever-present hurdle of public misconception must be overcome. While the benefits of modern roundabout installation can be effectively communicated to those of us in the industry, communicating those benefits to our public is a challenge unto itself.
The traditional roundabout, or traffic circle, suffers from a poor reputation in the United States. The word "roundabout" frequently conjures up memories of a bad driving experience abroad. However, modern roundabout design has been greatly improved from previous adaptations in Europe and along the East Coast. The large diameter, high-speed, multi-lane roundabout has evolved into a smaller diameter, slow-speed, one- or two-lane design that provides similar capacity to that of a traffic signal. Consequently, educating the public about the differences between a traditional roundabout and a modern roundabout is the first misconception that must be overcome in order to obtain public approval and acceptance.
The most common misconception of the general public regarding roundabouts is pedestrian safety. As the modern roundabout is usually substituted in place of a traffic signal, the public perceives the modern roundabout as unsafe when compared to the exclusive pedestrian crossing phase provided by a traffic signal. However, this perceived safety provided by a traffic signal as opposed to a modern roundabout is generally not the case for several reasons. Modern roundabouts deal with pedestrians by providing pedestrian crossings that are separated approximately one car length from the intersection. The splitter island, or median installed on each intersection approach, also provides a staging area for pedestrians so that only one lane of traffic needs to be crossed at a time. A pedestrian at a signalized intersection will need to cross three, four, or sometimes five lanes of traffic (50 to 75 feet in width), all the while being aware of vehicles approaching from four directions while crossing the intersection. A pedestrian at a modern roundabout crosses only one or two travel lanes (18 to 30 feet in width) at a time, and will only need to be concerned with traffic approaching from a single direction. Furthermore, the slower speeds encountered at a modern roundabout significantly reduce the severity of any vehicle-pedestrian collisions that may occur.
The general public is initially confused regarding bicycle use within the modern roundabout. A bicyclist approaching a modern roundabout has two options on how to use the intersection. A bicyclist may choose to merge with vehicular traffic and enter the intersection similar to a vehicle (the slow circulating speeds permit simultaneous bicycle-vehicle use) or dismount at an appropriately placed bicycle ramp and use the intersection as would a pedestrian. Wider sidewalks are installed adjacent to a modern roundabout to allow for walking bicycles.
Another common public misconception is the inability of roundabouts to serve truck traffic, or other large vehicles such as emergency vehicles or school buses. However, the serviceability of truck traffic in a modern roundabout is easily accomplished by use of a truck apron. A truck apron provides a mountable surface in the interior of the modern roundabout to accommodate the off-tracking of the rear wheels of large trucks. The truck apron is designed with a contrasting surface to that of the roadway to discourage use by passenger cars, and is frequently unnoticed by many drivers.
In addition to addressing public misconception, emphasizing additional benefits provided by modern roundabout installation is extremely effective in gaining public support. Aside from the technical benefits of increased intersection capacity and reduced vehicle delay, the modern roundabout provides an aesthetic improvement to an intersection and a community via the landscaped center island and other landscaped amenities. A landscaped center island helps break up the large monotonous lanes of asphalt that tend to dominate our streetscape. Landscape features within a modern roundabout can be sources of community pride and help the driver transition into adjacent neighborhoods.
It is surprising how quickly public opinion can change with a presentation that addresses the common misconceptions and emphasizes the unknown or unrealized benefits of the modern roundabout. I have seen detractors turned into supporters within minutes.
Regardless of how effective a presentation may be, there will always be members of the public who will find a negative aspect of your modern roundabout proposal. After a recent presentation, I was approached by a gentleman who was convinced that a proposed modern roundabout installation would not work because the headlights of the circulating traffic would disrupt the Friday night football game at the local high school located a quarter of a mile away. I had to punt on that one.
To reach Chris Doty, call (541) 504-2015 or send e-mail to firstname.lastname@example.org.