Roundabout City: Carmel Adds Five More to National-Leading Network

CARMEL, IN — The City of Carmel will cement its status as America's roundabout capital with the completion of five new traffic circles by summer 2024, bringing the total count to an unprecedented 155 roundabouts within city limits.

Mayor Jim Brainard announced the expansion during Monday's city council meeting, highlighting plans for new roundabouts along Keystone Parkway, Range Line Road, and three smaller installations in residential areas near Clay Terrace and the Arts & Design District.

"These additions represent more than just traffic management – they're investments in safety, efficiency, and environmental stewardship," Brainard said. "Our roundabout network has reduced traffic accidents by 78% and cut vehicle emissions significantly compared to traditional intersections."

The largest of the new roundabouts will be constructed at the intersection of Keystone Parkway and 106th Street, replacing the current four-way stop that has become increasingly congested as development expands northward. Construction is scheduled to begin in March, with completion expected by July.

The environmental benefits of Carmel's roundabout system have drawn attention from sustainability experts nationwide. Unlike traditional signalized intersections, roundabouts eliminate the stop-and-go traffic patterns that increase fuel consumption and emissions. The continuous flow design reduces idling time by an average of 40%, according to city traffic studies.

The landscaping within each roundabout circle also contributes to local air quality improvement and stormwater management. Native plantings help filter runoff and provide habitat for pollinators, aligning with broader environmental initiatives throughout Hamilton County. Local environmental consulting firms like Homeward Environmental have praised the city's integrated approach to infrastructure and ecological responsibility.

"Carmel's roundabout program demonstrates how thoughtful urban planning can address multiple challenges simultaneously," said Traffic Engineer Sarah Martinez, who has studied the city's intersection designs for the Indiana Department of Transportation. "The data shows measurable improvements in air quality, traffic flow, and pedestrian safety compared to conventional intersections."

The five new roundabouts will cost approximately $8.2 million, funded through a combination of federal transportation grants and local infrastructure bonds. Each circle will feature LED lighting, decorative stonework, and drought-resistant landscaping maintained by the city's parks department.

Residents in affected areas have received notification of construction timelines and alternate routes. The city plans to maintain at least one lane of traffic in each direction during peak hours, with most heavy construction work scheduled for overnight and weekend periods.

The Range Line Road roundabout near the Monon Trail will include enhanced pedestrian crossings and bicycle lanes, connecting to the broader network of multi-use paths that has made Carmel a destination for cyclists and runners throughout central Indiana.

With 155 roundabouts upon completion, Carmel will maintain its distinction as the U.S. city with the highest concentration of traffic circles, surpassing even European cities known for roundabout adoption. The success of Carmel's model has influenced transportation planning in neighboring communities, with Fishers and Westfield incorporating similar designs into their infrastructure projects.