What’s road lasagna and how could it benefit Michigan?

Aug 17, 2023

Construction workers use a stacking technique, nicknamed "road lasagna," to re-build Bellevue Road in Ingham County, Michigan using scrap tires. (Courtesy photo | EGLE)

A section of road between Lansing and Jackson had been sinking for years.

Adding more layers of asphalt to the stretch of Bellevue Road only sped up the problem. So the Ingham County Road Department turned to a new strategy, dubbed “road lasagna” by the Rieth Riley Construction crew renovating the road.

Named by after the Italian dish, the technique involves layering materials to offer stability beneath the surface. In this case, the layers included old tires filled with aggregate -- particulate like sand, gravel and stone -- along with shredded scrap tire and geotextile fabric.

“There are several places that have successfully used this,” said Kirsten Clemens, the scrap tire program coordinator for the Michigan Department of Environment, Great Lakes and Energy. “As far as I know, this is the first application of this in Michigan.”

For the Bellevue project, the process worked like this: The tires are placed in two rows in the bottom of the trench and filled with aggregate. A layer of aggregate is put over top, then a layer of scrap tire aggregate followed by a layer of geotextile fabric. The process is repeated three times before the road is eventually prepared and paved.

In total, the project used about 30,000 scrap tires and was complete in less than a week.

Since its completion last year, the 325 lineal feet of Bellevue Road near Onondaga has shown positive results, according to Clemens. She’s optimistic it could not only hold up for upwards of 20 years, but inspire other road commissions to incorporate the strategy for roads near wetland areas.

“There’s certainly a lot of application for this across the state in these areas where you have water going under the road in these wide sections,” Clemens said. “I would say probably every county in Michigan has a section of road that could use this.”

EGLE offers grant money to projects that aim to advance the use of scrap tires in the state. Funds can reimburse up to 50% of the cost to purchase scrap tires.

Ingham County received about $80,000 in grant funds for its Bellevue Road fix. It’s also been awarded almost $488,000 from the state to help fund a repair of Fitchburg Road in Bunker Hill Township. The latter project will use about 5,510 cubic yards of tire-derived aggregate, or the equivalent of about 250,000 passenger tires, to rehab Fitchburg in 2024.

Using recycled tires in road projects isn’t a new concept nationally, though it hasn’t been tried much in Michigan. Clemens said she hopes success of the Bellevue Road project may inspire more use around the state.

“What’s very interesting with my involvement with county road folks is if they have a successful project, they are the best advertising folks you’ll get,” she said. “They’ll talk about their successful projects and other county road commissions are always looking for these new tools and new methods.”

Michigan produces an estimated 10 million scrap tires annually. When recycled, the old tires can be used in road projects, or broken down and used to make mulch, fuel, aggregate for drain fields, or new tires and plastics.

It’s illegal to dispose of tires in landfills because of the hazardous impacts they can have on the environment and public health, such as become breeding grounds for mosquitos. Tire retailers will often take back old tires for a recycling fee, and the state organizes community cleanup events to collect used tires.

To find a registered tire recycler, visit Michigan.gov/scraptires or call 800-662-9278. Many retailers also accept used tires for a small fee, and there are community tire collection events, which can be found at Michigan.gov/recyclingdirectory.