Gravel Substitutes

Chip Sealing

• Small city or county governments often use gravel for rural roads, but when these roads get more traffic, they often need an upgrade to accommodate increasing traffic flow. The website for Washington County, Oregon reported that in the summer of 2010 it planned to use "chip sealing" to improve some of its roads. Chip sealing places a thin layer of asphalt over crushed rock and is a relatively inexpensive road improvement in comparison to pure asphalt.

Asphalt

• While paving over a gravel road or driveway with pure asphalt is a significant financial investment, it may be the best decision in the long run. In 2006, "Road Business," a newsletter for highway and transportation officials, recommended that gravel roads with traffic of 100 vehicles a day or more receive an upgrade. It further suggested that paved asphalt roads would reduce dust, provide safer driving and improve vehicle efficiency.

Coal Ash

• Many people rely on gravel to make their driveways and walks less slippery, but there are other materials that can cut through ice to provide foot traction. Coal ash is a toxic byproduct of coal mining that often requires storage, but some businesses have found applications for the ash and in the process save storage space. A March 2009 article on the CNN Tech website reported that coal producers were using the byproducts of coal for a variety of reasons. In some cases coal ash became "a gravel substitute" as a means of covering ice.

Rubber Chips

• Homeowners with septic tanks or similar waste disposal systems often use gravel in the drain fields. Drain fields are typically trenches dug about 3 feet below the surface of the ground where gravel or other substances filter wastewater. While gravel is somewhat absorbent and hospitable to organisms that break down human waste, shredded tires provide an environmentally friendly alternative to use in drain fields. West Virginia University's "Pipeline," a newsletter that focuses on wastewater issues, suggests using shredded rubber. Shredded tire "chips" do not break down into harmful elements, are light and easy to work with and are much cheaper than gravel.