Split-level roundabout planned at 146th/Hazel Dell in Noblesville

A major change is coming to one of Hamilton County’s most heavily traveled and crash-prone intersections, but the long-term project is still three years from getting off the starting block.

County officials are in the design phase of a plan to convert the four-way stop at the intersection of East 146th Street and Hazel Dell Parkway in Noblesville to a $32 million split-level roundabout interchange. Construction is expected to begin in the summer of 2026.

“It’s really going to calm things down and create a safer environment for our constituents,” Hamilton County Commissioner Mark Heirbrandt said. “It’s expensive, but we want to make sure safety is the priority.”

Preliminary designs produced by Westfield-based Butler Fairman & Seufert Inc. and Indianapolis-based CHA Consulting Inc. depict a roundabout on Hazel Dell. Entrance and exit ramps would connect the roundabout to an overpass on 146th Street.

The plan is similar to a $44 million split-level roundabout currently under construction less than 3 miles east at East 146th Street and Allisonville Road. In that project, crews will also widen the bridge over the White River west of Allisonville Road. The 146th and Allisonville project is expected to be complete in 2025.

“There will be about a year gap there when one of them should be done and we’ll be starting, so we’ll be able to see for sure how well it works at Allisonville Road,” Hamilton County Highway Director Brad Davis said.

In the nearly 25 years since Hamilton County began a project to widen and extend 146th Street, the street has become one of its major east-west arteries.

The extension project culminated in 2007 with 146th Street reaching Interstate 69’s Exit 10 as Campus Parkway.

“We started looking at the whole corridor on 146th Street because traffic volumes don’t go down in Hamilton County,” Davis said. “As people continue to move here, they do travel on these heavily traveled corridors.”

Now, the effort is to make the thoroughfare safer with fewer delays.

“It’ll eventually turn out to be similar to State Road 37 or [Keystone Parkway],” Heirbrandt said. “We’ll have interchanges, and it’ll be free-flowing.”

About 50,000 motorists cross the 146th and Hazel Dell intersection each day, according to the Hamilton County Highway Department.

Planning for the roundabout interchange began about five years ago, the same time a study of traffic incidents from 2015 to 2018 found about 100 crashes happened at the intersection in that time frame.

The most common crashes occur because drivers speed through red lights and hit vehicles making left turns. Davis said the combination of congestion and crashes meant the intersection needed attention and change.

He said a traditional roundabout would not have worked at the location due to the high traffic volumes.

“It’s going to be considerably safer for the motorists but also for pedestrians because of the length of time to cross multiple lanes on 146th Street,” Davis said. “We’ll have much better, safer pedestrian movements through there. We’ll have multi-use paths and sidewalks to accommodate people better.”

Hamilton County will seek grants to pay for the $32 million project. The Indianapolis Metropolitan Planning Organization awarded Hamilton County $8.7 million last year for the project at 146th and Hazel Dell.

The IMPO is central Indiana’s federally designated regional planning organization, which creates short- and long-range plans related to transportation, economic development, housing, safety, sustainability and other quality-of-life issues, according to its website.

The organization receives most of its funding from the U.S. Department of Transportation. Davis said a reason the county received funding from the IMPO was because the project is expected to reduce vehicle emissions by reducing the time cars sit in traffic.

“There’s lots of benefits to what we’re doing, and air quality and congestion kind of go hand-in-hand,” he said.

Hamilton County unsuccessfully applied for a $30 million grant from the U.S. Department of Transportation’s Safe Streets and Roads for All program. Heirbrandt said the denial was a surprise because improving the 146th and Hazel Dell intersection is “one of the most-needed projects” in the metropolitan area.

The Safe Streets and Roads for All Program was established following the passage in 2021 of the Bipartisan Infrastructure Law. Projects in Carmel, Indianapolis, Fishers and Westfield also received denials from the federal government.

“Obviously, they look at what the income levels are in Hamilton County, and we get screwed. But that’s pretty typical,” Heirbrandt said. “The people, even down at the Statehouse, a lot of times, think our streets are made out of gold and we don’t need any funding. I feel like I need to work 10 times as hard down there at the Statehouse to convince people that we do need the funding.”

Heirbrandt said the county is still determining how much land it will need to purchase for the project, but he said the roundabout will be shifted north from the current intersection to avoid impacting homes, especially a neighborhood on the southwest corner.

Businesses in the area include Indiana University Health Urgent Care Noblesville on the northwest corner, the Hazel Dell Crossing shopping center on the northeast corner and Riverview Health and Emergency Room Carmel on the southeast corner.

“We’re trying to listen to everybody and trying to work with everybody that we possibly can on this,” Heirbrandt said. “Every project is complicated. It’s a pain, but like people say, no pain, no gain.”•