A 330-foot-long concrete walking path is more than a safe route through the parking lot adjacent to the Paynesville Area High School addition. Under the path is a unique stormwater management system designed with tire-derived aggregate (TDA).

During construction of the parking lot, the existing path was dug down six feet, lined with a special fabric and filled with TDA. Approximately 46,000 tires were used to manufacture the TDA. Voss Plumbing and Heating installed the TDA in one day, using their heavy equipment to compact the material. Workers new to the material commented it was like driving on marshmallows, but there were no issues with the project.

Water running off from the building and parking lot will collect in the TDA. From there, water will slowly infiltrate into the soil. Should there be a large storm, there is an overflow into an existing storm sewer system.

The stormwater management plan was designed by Stantec. Jeremy Mathiasen, project manager, said TDA was the right choice for several reasons. “The biggest factor was space,” Mathiasen said. The alternative would have been to create a large open water feature, which would’ve reduced the parking area or green space. Being underground, we were able to maintain more parking area and keep the feature centrally located on the project. TDA helped us maintain green space and meet parking requirements."

Cost savings are also a consideration; alternative water management plans would’ve been more expensive.

TDA performs well. Mathiasen says there is a high void space with lots of room for water. The material is lightweight. It compacts well. It serves multiple purposes and meets multiple civil engineering needs. Maintenance is minimal. There is a clean out system that allows sediment to be flushed out if it builds up, but that isn’t expected to be an issue.

National studies on TDA show environmental benefits, Mathiasen explained. “Testing points to tire shreds and the steel in the shreds help treat nutrients in the water,” he said.

Monte Niemi, CEO of TDA Manufacturing, has been a champion of educating the construction and environmental industries on the benefits of using TDA. “TDA is an invisible workhorse in civil engineering applications,” Niemi said. “Across the country, it’s getting recognition for solving problems in the most cost-effective, environmentally friendly and technically sound ways.”