Wednesday, March 12, 1997

Stephenville dairy project sets good example

By J.T. SMITH / Farm Editor

Erath County is the No. 1 dairy county in Texas for production.

Modern dairies in the Stephenville area also are setting the trend in adapting to strict guidelines regarding any discharge from dairies. Producers are looking at various ways of protecting water quality.

At Stephenville, some local state, and federal agencies are working together for water quality improvement in a three-year project.

The project demonstrates the benefits of using constructed wetlands in a small agricultural watershed to reduce nonpoint source water pollution.

NPS pollution comes from several sources - urban runoff, construction activities, agricultural, and silvicultural (forestry) activities.

Surface and ground water can become contaminated when sediments, nutrients, pesticides, debris, oil and other elements enter local waterways and travel downstream into areas such as the North Bosque River.

These pollutants can cloud the water, reduce the water's vital oxygen supply and disrupt stream habitat, which in turn, affects plants and animals as well as humans who rely on the North Bosque River for water.

Project beneficial

"What we are concentrating on are areas that are not controlled or regulated, such as a grassed pasture or loafing areas, where runoff is naturally going to occur," says Dr. Ann Kenimer, Texas A&M assistant professor of agricultural engineering. "We are demonstrating a practice that is meant to be used with current on-farm management as an extra benefit for improving water quality."

Texas A&M faculty, working with the Texas State Soil and Water Conservation Board, installed constructed wetlands in a tributary of the North Bosque River called "Smith's Spring Creek."

The creek runs through the Texas Agricultural Experiment Station land and drains a small watershed of 1,750 acres.

What are constructed wetlands?

Constructed wetlands are created by altering the landscape to create man-made units that simulate natural wetlands. They provide benefits such as improved water quality and wildlife habitats.

The constructed wetlands were created by building berms in three ponds on Smith's Spring Creek and planting native plants - such as cattails and water primrose.

Since installing the berms and native plants, the team has begun monitoring the constructed wetlands' effect on the creek's water quality and aquatic life.

"Wetlands have a natural capacity to clean up water by biological, chemical, and physical means," Kenimer notes. "The water flows slowly through the wetlands due to plants. Solid material falls out, and there is a biological breakdown of organic matter and a transformation of nutrients."

Potential goes beyond dairies

"The project will also reduce the pollution potential from other activities such as row-crop operations, nutrient loadings from rural subdivisions from septic systems, and lawn care - as well as from natural sources such as ducks using the surface water," says Dr. Joe McFarland, TAES resident director.

"It is a total watershed approach that doesn't really address any one contributor of nutrients, but regardless of source, this methodology should result in better water quality for the entire watershed."

For more information about this program, contact Richard Egg, program manager, Statewide Management Program, TSSWCB, at (817) 773-2250.