Dust is a price many of us pay to live in the country. Some 70% of U.S. roads are unpaved, and the EPA says about 40% of dust particles come from these unpaved roads right in front of our homes.
All gravel roads give off dust. The U.S. Forest Service estimates that one vehicle traveling one mile each day down an unpaved country road will generate nearly a ton of dust over the course of a year. Multiply that by the number of vehicles that pass over the dirt road each day and you'll get an idea of the tremendous amount of dust that enters the atmosphere. This dust will travel up to 500 feet before it finally settles down.
The resulting problems are more than just a nuisance. Driving on dusty roads offers poor visibility, and thus a greater risk of accidents. Dust particles from nearby roads can also creep into adjacent homes where it can cause breathing problems such as asthma, bronchitis and coughing spells. Animals kept close to the road are also vulnerable.
If dust is a problem on the road in front of your farmstead, here are some ideas to help control the problem.
Plant a windbreak to block the movement of dust. Driving habits also make a difference. Keep vehicles in the driving lanes and off the road shoulders where dust tends to accumulate. Driving slowly, less than 15 mph, reduces the amount of dust kicked up by vehicles.
Spreading water over unpaved roads tames dust but results are only temporary. In years past, it was common to spread used engine oil to hold down dust, but this threatens the environment and is now illegal. Keep in mind that anything sprayed on a road surface can enter water supplies through wind or water erosion.
Today, chloride salts are among the most widely used dust suppressants. They work by pulling water from the atmosphere and binding it to road dirt. Calcium and magnesium chloride are the most popular. Sodium chloride, or table salt, is less effective. Chloride salts are corrosive to metals and can also result in slippery coatings on the road surface. After initial application, a follow-up treatment at a lower rate is usually needed to ensure long-term dust control.
Lignin sulfonate, more commonly called tree sap, is a by-product of pulpwood processing and is another widely used dust suppressant. This biodegradable product is used in many commercial dust suppressants because it acts as a binder to seal road surfaces and tends to work best when incorporated into gravel on the road surface.
The soybean industry offers soy soapstock, a by-product of soybean oil extraction. One application should provide three to four months of dust control. This noncorrosive and environmentally friendly solution works by penetrating road surfaces and bonding the gravel together.
It's best for neighbors to work together and with local road departments. The payoffs include safer roads, cleaner homes and fresh air. Also, road surfaces kept free of dust require less frequent blade maintenance by motor graders. That's a savings to taxpayers.
The ultimate solution? Pave the dirt roads. As much as elected officials would like to do so, they also know that paving every dirt road would cost a fortune and likely bankrupt the local government. If paving is the solution for your dirt road, it helps if you are on good terms with your county commissioners.