National Roundabouts Week – The Benefits of Modern Roundabouts

September 24, 2021

The Federal Highway Administration has made the third week in September National Roundabouts Week to highlight modern roundabouts’ safety and traffic moving abilities. Not only do modern roundabouts help improve traffic flow, but they are also great in reducing accidents and injury, in turn helping reduce the likelihood of needing to make an accident claim.


In honor of our headquarters being in the city with the most roundabouts in America, we wanted to celebrate this special holiday with some quick facts.


What is a roundabout? 

A roundabout is a type of circular intersection with yield control of entering traffic, islands on the approaches and appropriate roadway curvature to reduce vehicle speeds.


Modern roundabouts are different from rotaries and other traffic circles. For example, roundabouts are typically smaller than the large, high-speed rotaries still in use in some parts of the country. In addition, roundabouts are generally larger than neighborhood traffic circles used to calm traffic.


Roundabouts are a proven safety countermeasure because they can substantially reduce crashes that result in serious injury or death.


There are a wide array of benefits to roundabouts, including:

  • Improve safety
    • More than 90% reduction in fatalities
    • 76% reduction in injuries
    • 35% reduction in all crashes
    • Slower speeds are generally safer for pedestrians
    • Head-on-head high-speed right-angle collisions are virtually eliminated
  • Reduce congestion
    • Efficient during both peak hours and other times
    • Typically fewer delays
  • Reduce pollution and fuel use
    • Fewer stops and accelerations
    • Less time idling
  • Save money
    • Often no signal equipment to install, power and maintain
    • Smaller roundabouts may require less right-of-way than traditional intersections
    • Often less pavement needed
  • Complement other common community values
    • Quieter operation
    • Functional and aesthetically pleasing.
  • Meet a wide range of traffic conditions because they are versatile in size, shape and design


With Carmel, Indiana being the city with the most roundabouts in the US and where our home office is located, here are some facts specific to Carmel and their roundabouts:

  • The double-teardrop design that Carmel, Indiana, installed at busy intersections slashed injury crashes by 84 percent and reduced all crashes at these locations by nearly two-thirds.
  • Analysis shows that the conversion to roundabouts resulted in a 47 percent reduction in injury crashes overall.
  • Single-land roundabouts reduced total crashes and property-damage-only crashes by 51 percent and 50 percent.
  • Injury crashes dropped 50 percent at single-lane roundabouts and 15 percent at multilane roundabouts.


Roundabouts may seem unnecessary or tough to navigate at first, but once you get used to them and realize the immense impact they have had on vehicle safety and reduction of injuries, it’s hard not to love them.