This spill and other mishaps from hog confinement operations have fueled controversy about large-scale livestock farming. However, from a water quality perspective, large operations are just a part of the picture. There are thousands of small and medium-sized livestock operations employing a variety of waste management practices, with varying effects on water quality. Livestock operations are tremendously important to the state from an economic standpoint - and they have tremendous capability for environmental damage as well. Water quality can be affected by a variety of common manure management practices.
Many operators keep their animals in open feedlots.
Without protective measures, when it rains manure runs off into surrounding ditches, streams, and rivers. Manure may also infiltrate soils to reach the groundwater. In other operations, manure is kept in earthen or cement-lined storage structures or lagoons. Leakage or spills from these structures can also move into surface waters, soils, and groundwater. In addition, when manure storage facilities are emptied and too much manure is applied to cropland, or it is applied incorrectly, excess nutrients from the waste may contaminate surface waters and groundwater.