There are over a million miles of public documented unpaved roads in the United States alone. That means there's a high chance you've driven on one yourself and have likely experienced one of the drawbacks of an untreated dirt road. We're talking about dust, mud, and rutting. Most people always think of dirt roads as having dust issues and have environmental issues, which is extremely common. Another massive issue with dirt roads is their reliability. Dirt roads are usually highly unreliable. If a rainstorm happens, the roadway could wash away, or if the snow melts, the roadway could wash away. When the road is unreliable, the citizens will have to allow for more time to travel on the road or, worse, not use the roadway because it is unsafe.
The main cause of dust in untreated dirt roads comes down to the soil that the road is constructed with. Dust is made up of many small particles in the soil being kicked up into the air from an interaction with the road, such as cars and wind. The higher the number of tiny particles in the soil, the more likely the road will have problems with road dust.
Clay soils have the smallest particle size, this is important because it explains why dirt roads with dust problems tend to have rutting problems as well. Clay loves to take in water, and when it does, the properties of the soil change. Specifically, the plasticity of the soil increases, making it more pliable. This change in plasticity is what makes the soil give way during heavy rain, leaving large ruts in the road from car tires. When the rain stops and the soil eventually dries, the clay particles shrink and become rigid, creating cracks in the dirt road's surface and leaving deep imprints from tires.
This plasticity feature in clay particles is also why most dirt roads become very muddy when it rains. Clay can only absorb so much water, and after it absorbs a certain amount, it reaches optimum moisture. At this point, the soil can't absorb any more water and begins to feel more like mud or liquid.
Road builders will use several soil stabilization treatments during the construction phase to reduce these symptoms. These techniques focus on building the strength of the road surface so that a variety of traffic weights and weathers can pass through without disturbing the road. Each method has its pros and cons, varying in environmental impact, effectiveness, and longevity. Some products even work better for specific soil types, such as Perma-Zyme, which works best on soils high in clay content.
If there are so many products out there that fix these problems, why do we still have dirt roads kicking up an immense amount of dust or completely washing away when it rains?
It's expensive to build a dirt road. Between the cost of the hauling, labor, and equipment, there just isn't enough budget to go around. Not only that but some soil stabilization products, like magnesium chloride, wear off in 6-12 months and dissolve away when it rains. That adds a significant additional annual cost for maintenance on each road the solution is applied to. For a small county road commission, that cost can be devastating.
That's where enzyme-based soil stabilizers, like Perma-Zyme, come in. Since the formula targets organic content already present in the soil, and clay is the most common soil type that produces significant issues in dirt roads, no hauling is needed. The construction can utilize the native soil on-site without bringing in or removing material. In addition, the treatment lasts over 10 years, eliminating maintenance costs. Overall, using Perma-Zyme for a dirt road reduces construction costs by up to 80%.