soil in these areas turns to mud, creating an unhealthy environment for optimal livestock production, poor traction for farm equipment, and potentially poor surface water quality. Once these areas dry, they may provide rough and possibly hazardous footing for the animals.

After the vegetation in these concentrated areas is destroyed, the soil is bare and subject to erosion. In addition, once wet soil that has been trampled by livestock dries, it has a greatly reduced infiltration rate, and thus a much higher potential for producing runoff of soil and manure. Both of these conditions are conducive to creating a water quality problem.

The installation of geotextile fabric combined with gravel can help provide a proper surface that animals, humans, vehicles, and equipment can travel on, and can also provide an erosion control benefit. Usually, the cost for the fabric and gravel will be 25 to 33% of the cost of concrete but with today’s escalating cement and steel rebar prices, expect an even better bargain.

Geotextile fabric applications are designed to keep soil and gravel (or other earthen materials) separate. By keeping the soil and gravel separated, the fabric improves the stability, load bearing capacity, and drainage of the site. A geotextile fabric installed as a layer between gravel and soil layers forms a barrier against the movement or intermixing of the soil and gravel . In applications where gravel is placed on top of a soil layer, as in conventional driveways, farm roads, or graveled areas, the separation provided by the fabric helps the gravel maintain its position load bearing capacity throughout its life. When properly installed, the fabric can help distribute loads from animal and vehicular traffic by reducing the impact of a load, and redistributes the localized pressures over a larger area of subgrade material (soil or other earthen material in the lower layer). Overall, there is great improvement in the support properties of the system. Subsequently, the need for additional gravel each spring is greatly reduced, if not eliminated.

Drainage is enhanced when the gravel and soil are kept separate and the soil is not allowed to fill in the voids in the gravel layer. Water movement within the surrounding soil or earthen materials can be improved and managed since the fabric allows water to pass through it, and thus does not impede the vertical or horizontal movement of water. Also, if the soil layer above or below the geotextile is impermeable, the fabric may act as a conduit for water flow.

The original development of geotextiles focused largely on non-agricultural uses such as roadbed and parking lot construction. However, there are many related agricultural applications including lanes to pasture paddocks, feedlots, and barnyards; livestock watering areas; silage bag and round bale storage and feeder areas; driveways for farmsteads and other farm roads; drainage ditch and stream crossing areas; subsurface drainage tubing connections; aprons for open-side livestock barns; and to extend existing concrete, paved, or graveled areas.

Selecting the proper gravel to use on top of the geotextile fabric is very important. Larger stone alone will not pack easily, will contain large open voids, and will not allow ease of travel by livestock. Gravel that is too small will not provide sufficient structural support. When the gravel layer is saturated, animals and equipment can sink into the layer.

For livestock operations, a minimum of six inches of gravel should be placed on top of the fabric. A 411 grade of gravel (gradation of gravel sizes from 1.75 to 0.5 inch with fines) works well for livestock traffic. In areas where round bales are fed to livestock, and in feedbunk areas, the gravel depth should be increased to eight inches. For driveways with heavy truck or tractor traffic, a minimum gravel depth of eight inches is recommended.

Gravel grade 304 (gradation of sizes from 1.25 to 0.5 inch) is recommended for driveways or bale and silage bag storage areas. Although grade 310 is sometimes recommended for these applications, the size gradation can be highly variable and inconsistent. Check with your local gravel supplier about the quality of the 310 grade. Approximately 110 tons of gravel will cover one 500 square yard roll of geotextile fabric with a six-inch thick layer of gravel. Once properly placed on the fabric, smoothed and packed, the gravel mixture forms a hard packed surface that supports both equipment and animal traffic.

Proper installation of geotextile fabric with gravel, soil or other earthen material as a topcoat is best accomplished when the soil at the site is dry. The following is a series of tips to ensure proper site preparation, geotextile fabric installation, and cover material application at the site.

• Clear the area of any sharp objects, stumps, and debris.

• Grade the existing soil surface to provide adequate, but not excessive, surface drainage.

• Unroll the geotextile fabric over the application area. On a windy day, the fabric will need to be secured with pins, sod, stones, etc.

• Place the gravel on the fabric. It is best to back dump when unloading and spreading the gravel on the fabric with a truck. Then complete the final spreading and smoothing with earthmoving equipment like a dozer, front-end loader, skid loader, or scraper.

• Care should be taken when backfilling and compacting the gravel. Geotextile fabric is tough, so it can be driven on. However, truck tires may pull the fabric, causing it to wrinkle. This condition may affect the proper installation and performance of the system since less area may actually be covered by the fabric.

• If it is necessary to overlap the fabric in order to cover a larger area, a minimum of a one foot overlap is required for proper use. In order to ensure a minimum of one foot of overlay after the placement of the gravel or other topcoat, it is recommended that the fabric be laid out with a two-foot overlap before placing the gravel on the fabric. Once placed, the gravel should be spread in the same direction as the geotextile fabric overlap to avoid separation between the two pieces of fabric. Staples are available to help hold the fabric in place.

Since geotextile fabric provides separation between soil and gravel, or other earthen materials, the annual addition of gravel is usually not necessary as with conventional driveways and farm roads. If the area where the geotextile fabric was installed receives manure, it can be scraped periodically with a skid loader or box scraper. Gravel is sometimes removed during this process, and it should be replaced. The original depth of gravel should be maintained throughout the life of the system. Repairs should be made on an as needed, but timely, basis.