Virtually all drinking water and recreational use of water resources comes from groundwater or surface water. Many other uses, such as food processing and irrigation, dependent on abundant supplies of high-quality water. Effects of poor manure management Loss of fertilizer nutrients. Applying too much manure, at the wrong time, or improperly handling it in other ways releases nutrients into the air or into ground or surface waters. Thus, instead of nourishing crops, nutrients become pollutants.
Excess nitrogen can leach through soil into groundwater.
Manure contamination can increase nitrate levels in ground water and cause bacterial contamination and fish kills in surface waters. Excess phosphorus can be contained in erosion or runoff from fields and accumulate in surface water impoundments such as ponds and lakes. This phosphorus can stimulate unwanted plant growth, such as algae, which causes turbidity and other undesirable conditions in the water. A common misuse of manure is to spread it on a field and then, in addition, apply commercial fertilizer to supply a crop's nutrient needs with no consideration for the manure's nutrient value. An efficient manure management and application system meets, but does not exceed, nutrient needs of the crop.