Maintaining a Healthy Water Supply While Growing a Healthy Food Supply: Legal Tools for Cleaning Up Agricultural Water Pollution
40 Pages Posted: 8 Oct 2015 Last revised: 9 Dec 2015
Date Written: May 1, 2014
Although agriculture is one of the most significant and pernicious causes of water pollution in the U.S., federal environmental laws designed to protect water resources exclude or exempt most agricultural activities. State efforts to address water quality impacts from agriculture have met with little success. The challenge of finding a way to reduce agricultural water pollution without causing severe economic harm to farmers is one of the greatest environmental challenges of our time.
Large scale industrialized agriculture, with its heavy reliance on fertilizer, pesticide and water inputs, is a major contributor to water pollution. Agricultural practices can cause serious adverse impacts to the quality of both groundwater and surfacewater. Rain or irrigation water that falls on farm fields, picks up water soluble pesticides such as atrazine and nutrients such as nitrites found in fertilizers, causing them to leach into groundwater. Rain and irrigation water that is not absorbed into the soil runs off of agricultural fields carrying with it a variety of pollutants which ultimately end up in surface water bodies. Run-off from farm fields frequently contains high levels of sediments from soil erosion from tilled fields, pesticides and fertilizers. Pesticides that enter waterbodies can adversely impact aquatic life. Nutrients from fertilizers can cause waterbodies to be hypereutrophied, which can severely impact submersed plants and aquatic animals. Run-off of sediments from soil erosion due to tilling can clog streams and fill in shallow areas in water bodies, thereby reducing habitat and light availability to submersed plants. A report by the National Water Quality Inventory identified agricultural nonpoint source (NPS) pollution as “the leading source of water quality impacts on surveyed rivers and lakes, the second largest source of impairments to wetlands, and a major contributor to contamination of surveyed estuaries and ground water.”
The federal Clean Water Act (CWA), the primary federal authority for addressing water pollution, has been largely successful at reducing water pollution from point sources such as wastewater treatment plants and industrial discharges through the National Pollutant Discharge Elimination System (NPDES). A major shortcoming of the NPDES program, however is that it does not apply to NPS discharges, including most agricultural runoff. Although most pollutant discharges to waterbodies from agriculture are not subject to NPDES regulation, the federal CWA does require states to establish water quality standards and total maximum daily loads (TMDLs) that can be used by the states to address agricultural water pollution through regulatory or non-regulatory mechanisms. A TMDL tells you how much of a particular pollutant a particular water body can assimilate without a violation of a water quality standard. Thus, the establishment of TMDL’s is an important step in ensuring that state water quality standards are met. The greatest challenge, however, is the allocation of TMDLs among all point and nonpoint source dischargers, and the implementation of the TMDLs. For point source discharges, TMDLs are allocated and implemented through the NPDES permit program and may require pollution reductions beyond what would be required using only technology-based standards. For nonpoint sources such as agricultural, the allocation and implementation of TMDLs is much more daunting.
This Article will explore a number of legal mechanisms that could play a role in ensuring that discharges from agricultural activities do not cause or contribute to violations of water quality standards. Specifically, this article will evaluate the relative effectiveness of: 1) narrative nutrient criteria and numeric nutrient criteria, 2) TMDL implementation through regulatory and nonregulatory mechanisms; and 2) Design-based standards such as Best Management Practices (BMPs) and performance-based standards in reducing water pollution form agriculture. The Article will draw on experiences from the State of Florida, including Everglades’s restoration efforts, and efforts to reduce agricultural pollution in the Chesapeake Bay basin to demonstrate the efficacy of a variety of approaches and will suggest a multifaceted, watershed-based approach comprised of a combination of regulatory and nonregulatory federal and state efforts.
Keywords: water law, TMDLs, Water Quality Trading, agriculture
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