Water Quality Challenges

Water quality can be degraded by contaminants contained in manure, from water used at milking centers, from silage leachate, and from open lot runoff. These potential pollutants typically follow one or more possible pathways to water.

Animal manures contain both organic and inorganic forms of phosphorus. When manure mineralizes, organic phosphorus becomes inorganic phosphorus in solution and is available to plants. Some organic phosphorus is transformed to inorganic form shortly after application but other phosphorus will remain in organic form

Nutrients in manure are potentially valuable resources for the management of soil fertility, but these nutrients are potential pollutants as well. Only 10 to 40 percent of the nutrients consumed by animals may end up in the marketed product; the rest is excreted in feces and urine. Manure contains all nutrients needed by plants, but nitrogen and phosphate generally have the most agronomic significance in Nebraska.

Pathogens, typically microbes (e.g., bacteria, viruses, protozoa, fungi) or parasitic worms, are organisms capable of causing infection or disease in other organisms, including humans, wild and domestic animals, and plants. Several pathogens naturally occur in livestock and poultry manure and under certain circumstances may pose a risk to human health.