Shredded Tires Under an Indiana Highway: A Recycling Experiment That Worked
What can you do with millions of old car tires? In 2001, engineers in Indiana tried an unusual answer. They buried shredded tires under a stretch of State Road 31 near Lakeville. Then they watched the road for a year. The results were surprisingly good.
What the Project Actually Did
The idea was simple. Old tires are a huge waste problem. They pile up in landfills and stockpiles. They can catch fire and are hard to get rid of. But shredded tires are light, springy and cheap. So engineers used them as fill material inside highway embankments. An embankment is the raised bank of earth that supports the road.
Instead of using only soil and gravel, the project mixed in shredded scrap tires. This gave the road a lighter base. It also found a useful second life for waste that would otherwise sit in a dump.
What One Year of Monitoring Showed
Officials tracked the road for a full year. They looked at two main risks.
The first risk was settlement. Settlement means the ground sinks or shifts under the weight of the road. If fill material compresses too much, the road surface can crack or dip. In this project, settlement was negligible. The road held its shape well.
The second risk was heat. Shredded tires can sometimes generate heat inside a large pile, and in the worst cases this can lead to smoldering or fires. Monitoring found no major heating problems. The tire fill stayed stable and cool.
So the experiment passed both tests. The road stayed solid, and the tire fill behaved itself.
Why This Matters for Waste and Roads
Every year, the world throws away enormous numbers of tires. Each one is tough, durable and hard to break down. That is bad for landfills but good for construction. A tire that lasts decades in a dump can also last decades as lightweight road fill.
Using shredded tires in embankments could cut waste and reduce the need for mined gravel and soil. It may also make roads lighter and more stable in some conditions. For taxpayers, that could mean lower material costs over time.
So Why Isn’t Everyone Doing It?
Here is the frustrating part. Even though the Indiana project worked, the technique has not spread widely. Two big barriers stand in the way.
The first barrier is regulation. Highway rules are often written years in advance and based on familiar materials. New methods face extra testing, paperwork and caution. Officials want to avoid risk, so proven but unfamiliar ideas can stall.
The second barrier is contractor bias. Builders and engineers tend to trust what they know. Shredded tires are still seen by some as risky or strange, even when studies show they work. Changing habits in construction is slow.
The Bigger Lesson
The Lakeville project is a small story with a large point. Green building ideas often work in the field but struggle to become standard practice. Good data is not always enough. Rules, habits and comfort with the old way can hold back change.
For investors, this is a useful reminder. Companies and projects tied to recycling and sustainable infrastructure may have real technical promise. But adoption can be slow because of policy and industry culture. Watching regulation and contractor behavior matters as much as watching the science.
The Indiana road shows that shredded tires can carry traffic safely. The next challenge is convincing the people who build roads to use them.
