Roundabouts are a common form of intersection control used throughout the world and increasingly in the United States.  According to the National Cooperative Highway Research Program‘s Report 672, roundabouts have been demonstrated to be safer for motor vehicles and pedestrians than other forms of at-grade intersections. 

TA has analyzed and designed roundabouts incorporating features accommodating a particular set of circumstances.  Such designs have included:

• Channelized lanes
• Expandable design to accommodate a second circulatory lane
• Bike and pedestrian accommodations
• Diverging ramps to a shared bike/ped path
• Traversable central island to accommodate larger vehicles

TA helped design a roundabout near West Virginia University’s football stadium that can be converted during game days with an additional entry/exit accessing a parking lot.  The roundabout is somewhat unique in that it lies on a 7 percent grade.