If you manage a feedyard, you manage runoff.
Historically, a retention pond that captures and holds runoff from feedyard pens has been the way managers deal with the result of rain and snow. In fact, it's the only way, as far as the Environmental Protection Agency (EPA) is concerned. Up to now, that is.
Researchers with USDA's Agricultural Research Service at the U.S. Meat Animal Research Center at Clay Center, NE, have been looking at an alternative to the standard feedyard retention pond.
Under this system, runoff containing manure solids is channeled to a small, temporary storage basin at the base of the feedyard. This basin holds runoff long enough to let the solids settle to the bottom, which takes just a few minutes.
The remaining liquid is drained through distribution tubes that provide even dispersal over a vegetative treatment area, essentially a grassy field. The drainage pipes control the flow so that a full basin empties in 6-8 hours. In the fall, solids are removed from the basin and spread as organic fertilizer.
At the Clay Center research facility, the vegetative treatment areas are about twice the size of the feedyard pens, a size that efficiently handles runoff water and manure nutrients. The grassy area produces hay, and after eight years of data, the scientists are confident the technology is environmentally sustainable.
Tests on the hay harvested from the grassy fields show the nitrogen contained in the hay equaled or exceeded the amount of nitrogen they estimate would have entered the area from the runoff. And after four years, there's no evidence of water leaching from the field.
According to John Nienaber, project research leader, the vegetative treatment area system has been conditionally approved by the EPA. Among the system's benefits are that it requires minimal maintenance, eliminates the need for costly pumping, and significantly reduces waste storage time, which cuts out standing water and the odor problems that arise.
“Our objective was to design runoff-control systems that require minimal operator input and use standard equipment to manage,” says engineer Bryan Woodbury. “These systems can incorporate more sophistication, but each level adds costs and management time to ensure proper operation.”
In future studies, the researchers plan to compare the influence of basin size on a system's ability to separate solids when runoff pressure is higher, such as during a heavy downpour. But for feedyards looking to redesign their runoff-handling system, this low-cost, low-tech system might be an alternative.