The Debate about Farm Nitrates and Drinking Water

High nitrate levels in groundwater are impacting and restricting use of municipal water supplies in some locations. Nitrogen is a primary nutrient necessary for plant growth. Nitrogen is also a primary component of crop fertilizers, but when nitrogen is not used by crop plants, it can convert to nitrates and move with groundwater in the soil. Nitrates can contribute to pollution of lakes, rivers, and streams. Community groups and municipalities are filing citizen lawsuits under federal laws to restrict the use of manure and fertilizers that elevate nitrate concentrations in water supplies. While the federal water and pollution laws have exemptions for field application of livestock wastes and field runoff, the community groups and municipalities are charging that those exemptions do not apply in cases of nutrient application resulting in polluted drinking water. In new applications of federal law, their arguments are convincing courts to assess nitrate liability to farmers and restrict farming operations. When nitrate concentrations exceed the drinking water standard, community groups, and municipalities are looking to the courts for relief. A federal court in Washington State ruled that manure application that resulted in nitrates leaching into groundwater was the same as open dumping of garbage, holding the dairy farm liable for the nitrate contamination of ground water (United States District Court, Eastern District of Washington, 2015).