A City That Chose an Unconventional Path
Carmel, Indiana made a bold transportation decision by replacing traditional intersections with roundabouts, reshaping traffic safety, fuel efficiency, and long-term urban costs.
Why Traditional Intersections Cause More Crashes
Traffic lights and stop signs create conflict points where high-speed collisions, especially T-bone crashes, are more likely to occur.
The Decision to Embrace Roundabouts
Since 1996, Carmel invested in roundabouts as a long-term safety strategy rather than relying on short-term traffic signals.
What Makes Roundabouts Safer by Design
Roundabouts force slower speeds and eliminate head-on and right-angle crashes, significantly reducing collision severity.
Crash Reduction Results in Carmel
Studies show Carmel reduced total crashes by around 40 percent after installing roundabouts citywide.
Dramatic Drop in Injury Crashes
Even more impressive, injury-related crashes fell by nearly 80 percent, saving lives and preventing serious harm.
Why Slower Traffic Saves Lives
Lower speeds mean drivers have more reaction time and crashes occur with far less force.
Fuel Savings Add Up Every Year
Each roundabout saves approximately 24,000 gallons of fuel annually by reducing idling and stop-and-go traffic.
Cutting Carbon Emissions Through Design
Less idling directly reduces vehicle emissions, helping create cleaner urban air quality.
Economic Benefits Beyond Safety
Every roundabout saves roughly $180,000 in long-term operational and maintenance costs compared to traffic signals.
Lower Maintenance Than Traffic Lights
Roundabouts require no electricity, fewer repairs, and minimal ongoing maintenance.
Keeping Traffic Moving Smoothly
Continuous flow improves commute times and reduces driver frustration during peak hours.
Emergency Vehicle Efficiency
Roundabouts allow emergency vehicles to pass through intersections faster than signal-controlled roads.
Adapting Drivers to a New System
Initial resistance faded as residents became comfortable navigating roundabouts safely.
Public Education Played a Key Role
The city invested in driver education to ensure smooth adoption of roundabout traffic rules.
Improved Pedestrian Safety
Shorter crossing distances and slower vehicle speeds improve safety for pedestrians and cyclists.
Urban Aesthetics and Community Appeal
Many roundabouts feature landscaping and public art, enhancing neighborhood appearance.
Why Carmel Built So Many Roundabouts
The city focused on consistency, making roundabouts the standard rather than an exception.
Long-Term Urban Planning Vision
Carmel prioritized sustainable infrastructure that delivers benefits for decades.
Lessons for Other Cities
Carmel proves infrastructure choices can dramatically impact safety, cost, and environmental health.
Conclusion
By building about 150 roundabouts, Carmel, Indiana created a safer, cleaner, and more cost-effective city, demonstrating how smart road design saves lives, fuel, and public money.