Biological Systems Engineering


Date of this Version



Journal of Environmental Quality, Vol. 6, no. 3, July-August 1977.


Copyright 1977, ASA. CSSA. SSSA.


Collection, storage, and ultimate land disposal of livestock feedlot runoff is becoming a more common practice as a result of increasing state and federal regulations prohibiting uncontrolled discharge of runoff. As a result of chemical, physical, and biological actions during the storage phase, the runoff applied to land from storage is often greatly different from that entering storage directly from the feedlot. This study was designed to observe those changes in the runoff during storage, and to evaluate their effect on land disposal practices. Six concrete paved feedlots with runoff control systems were studied, with emphasis on variations in nitrogen, phosphorus, and potassium in holding ponds used for storing runoff. Seasonal variations in nutrient content of the holding ponds result from precipitation patterns, nutrient losses, and other factors. Early spring dewatering of the holding ponds, followed by frequent summer dewatering if possible, will result in the best conservation of nutrients. Large differences in nutrient content of holding ponds were observed for different species of livestock, with stored swine feedlot runoff containing nearly eight times as much nitrogen as stored beef feedlot runoff.