What happens to old tires once they’ve been discarded? While many may end up in the landfill, in Dickinson County, they may just end up beneath your wheels.
If you’ve been to Dickinson County, there’s a chance you’ve driven on recycled tire asphalt. The Dickinson County Road Commission (DCRC) is the northernmost agency in Michigan to experiment with recycled tires, or engineered crumb rubber (ECR). According to Lance Malburg, PE, DCRC county highway engineer, the county “has a culture that is open to exploring new ways to do things.”
While warmer-climate states have used ECR in roads, the concept is relatively new. ECR-hot mix asphalt (HMA) has been proven to offer a smoother, quieter ride and last longer than traditional asphalt. It is also more economical and flexible in formula, and provides a use for old tires.
For Dickinson County, collaboration is key. The county’s proximity to Michigan Technological University has led to fruitful partnerships and advancements in road construction.
“Being so close to Michigan Tech, we try to take advantage of working with the University on new ideas,” Malburg said.
“This particular project came about because it was something a professor at Michigan Tech had been researching and wanted to study in the real environment. Dickinson put in $250,000, we received a $300,000 grant and Michigan Tech contributed $100,000. That’s relatively unheard of for the University.”
DCRC’s ECR-HMA project is on County Road 607, north of Iron Mountain. Composed of three half-mile sections, the project combines two segments of “dry mix” ECR with one segment of traditional asphalt as the experimental control.
CR 607 was completed this past June, although it will be months before the DCRC can analyze the results of the ECR HMA technology. However, Michigan Technological University completed early audio tests, which showed improvement in the road noise. Ultimately, this technology could provide UP residents with a better driving experience.
“With the process being more efficient, county residents can get out and enjoy improved roads more quickly than with traditional methods,” Malburg said.
For more about Dickinson County’s integration of ECR roads, read the latest edition of Crossroads, the quarterly journal of the County Road Association (CRA) of Michigan, which can be viewed digitally or downloaded at https://micountyroads.org/newsroom/crossroads/.
The 83 members of the County Road Association of Michigan represent the unified voice for a safe and efficient county transportation infrastructure system in Michigan, including appropriate stewardship of the public’s right-of-way in rural and urban Michigan. Collectively, Michigan’s county road agencies manage 75 percent of all roads in the state, including 90,000 miles of roads and 5,700 bridges. County road agencies also maintain the state’s highway system in 64 counties. Michigan has the nation’s fourth-largest local road system.
