Submitted to: American Society of Agri Engineers Special Meetings and Conferences Papers
Publication Type: Other
Publication Acceptance Date: July 28, 2002
Publication Date: N/A
Interpretive Summary: Precipitation runoff from beef cattle feedlots is typically collected and retained in large volume ponds. These ponds are relatively expensive to construct and may leak after a few years. A runoff control system was designed and built that eliminated the need for traditional long-term storage ponds. The system featured a temporary storage basin for settled solids. Liquid was drained by gravity to a grass hay field where water and nutrients were utilized. Up to 80% of solids carried in the runoff were settled in the basin. No runoff was discharged from the grass field during a 3-year period, indicating all runoff was used by the crop. Also, total nitrogen removed by the hay crop equaled or exceeded the amount released from the settling basin. The passive beef cattle feedlot runoff control and treatment system appeared to adequately treat runoff and protect the environment.
Technical Abstract: Research has shown that nutrients from feedlot runoff can infiltrate beneath long-term storage ponds. Pond embankments' wetting and drying cycles and weed growth form root channels that facilitate infiltration. A passive runoff control system was designed and constructed to collect and store suspended solids, provide temporary liquid storage, and evenly distribute nutrient-laden discharge water across a vegetative filter strip. The objectives of this project were to evaluate the suspended solids and nutrient removal efficiency of a passive runoff control system. The system effectively reduced the mass of total and volatile suspended solids, and chemical oxygen demand by 80, 67, 59%, respectively. Significant reductions of these constituents in the runoff water as it passed through the system were measured for most precipitation events. No water was measured exiting the vegetative filter strip during the three-year period of this study. Therefore, the discharge water was effectively used for hay crop production. The estimated total nitrogen load in the discharge water entering the vegetative filter strip was equivalent to or less than the total nitrogen removed by the crop. The system robustness was demonstrated during feedlot pen renovation when significant reductions in contaminant concentrations were measured for almost all precipitation events during the sampling period. It was concluded that the passive runoff control and treatment system adequately removed contaminants from feedlot runoff while effectively using the discharge water for hay production.