The project team studied all types of intersections to determine which treatments would work best. While a traffic signal may help direct all the directions of traffic and turns, installing new traffic signals can result in an increase in rear-end crashes.
In rural areas, new traffic signals are associated with a 77 percent reduction in angle crashes, but also a 58 percent increase in rear-end crashes, which can be severe and fatal in high-speed areas. Traffic signals do not address speed at an intersection – roundabouts do reduce speeds. Often, drivers accelerate through an intersection to try to make it through before the signal turns red, which is dangerous.