This video segment adapted from FRONTLINE: “Poisoned Waters” describes the problem of water pollution from chicken waste. On the Chesapeake Bay’s Eastern Shore, large-scale chicken farms dominate the landscape. These factory farms produce a bountiful supply of cheap chicken, but also an excess of chicken manure. Runoff from these farms, which is largely unregulated, flows into rivers that pollute the bay. While chicken farmers and chicken companies debate who should be responsible for the waste, the industry has successfully resisted pollution control regulations, arguing that voluntary practices are better.
The agricultural industry is a major source of water pollution that endangers human health. Runoff from farms can carry contaminants such as toxic chemicals from pesticides, as well as pathogens and diseases from animal waste. In fact, the waste from factory farms, which raise a large number of animals in confined quarters, is a key problem with which farmers are struggling. Factory farms produce meat and animal products at relatively low cost, but because of the high density of animals, they also produce an excess of animal waste.
What can farmers do with their animal waste? Poultry litter—the bedding used on chicken farms to cover the floors—consists of dry materials such as wood shavings, straw, and peanut shells. After chickens have used the litter, it also contains manure, feathers, and feed. Because the litter contains agricultural nutrients such as nitrogen and phosphorous, this nutrient-rich litter has traditionally been used as fertilizer for crops. However, the concentrated number of animals on a factory farm produces far more fertilizer than the farmer can use. Chicken farmers can sell their litter to nearby farms, but it is not economical to ship the litter long distances. So in areas where poultry farms produce more fertilizer than is needed by farmlands, the soiled litter needs to be stored and disposed of in some way. However, litter stored in sheds and trenches can cause pollution as runoff from the storage areas contaminates local waterways.
Why not just put more litter on the crops as fertilizer? Too much fertilizer can lead to high amounts of nutrient runoff and water pollution. Farmers need better solutions to get rid of their waste.
There are some new options on the horizon. Some farmers turn chicken litter into dried fertilizer pellets that can be transported out of state; or they dry and bag it for gardening fertilizer. However, these strategies have not yet proven cost-effective. Another option is to use chicken litter as fuel. A poultry-litter-fired power plant in Minnesota, which opened in 2007, was the first of its kind in the United States. However, burning biomass like chicken litter has generated controversy because of the possibility of increased air pollution.
Academic standards correlations on Teachers' Domain use the Achievement Standards Network (ASN) database of state and national standards, provided to NSDL projects courtesy of JES & Co.
We assign reference terms to each statement within a standards document and to each media resource, and correlations are based upon matches of these terms for a given grade band. If a particular standards document of interest to you is not displayed yet, it most likely has not yet been processed by ASN or by Teachers' Domain. We will be adding social studies and arts correlations over the coming year, and also will be increasing the specificity of alignment.