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Protecting Water Quality from Agricultural Runoff

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Protecting Water Quality from Agricultural Runoff Protecting Water Quality EPA 841-F-05-001 from AGRICULTURAL R UNOFF Clean Water Is Everybody’s Business he United States has more than T330 million acres of agricultural What Is Nonpoint Source Pollution? land that produce an abundant supply Nonpoint source (NPS) pollution, unlike pollution from point sources of food and other products. Ameri- such as industrial and sewage treatment plants, comes from many can agriculture is noted worldwide for its high productivity, quality, and diffuse sources. Polluted runoff is caused by rainfall or snowmelt efficiency in delivering goods to the moving over and through the ground. As the runoff moves, it picks consumer. When improperly managed up and carries away natural and human-made pollutants, finally however, activities from working farms depositing them into watersheds through lakes, rivers, wetlands, and ranches can affect water quality. coastal waters, and even our underground sources of drinking water. In the 2000 National Water Quality Inventory, states reported that agricul- Did you know that runoff from farms is the leading source of tural nonpoint source (NPS) pollution impairments to surveyed rivers and lakes? is the leading source of water quality impacts on surveyed rivers and lakes, to reduce pollution also increase In addition, other pollutants like the second largest source of impair- productivity and save farmers and fertilizers, pesticides, and heavy metals ments to wetlands, and a major ranchers money in the long run. are often attached to the soil particles contributor to contamination of sur- and wash into the water bodies, causing There are many government programs veyed estuaries and ground water. algal blooms and depleted oxygen, available to help farmers and ranchers Agricultural activities that cause NPS which is deadly to most aquatic life. design and pay for management pollution include poorly located or Farmers and ranchers can reduce approaches to prevent and control managed animal feeding operations; erosion and sedimentation by 20 to NPS pollution. For example, over 40 overgrazing; plowing too often or at the 90 percent by applying management percent of section 319 Clean Water wrong time; and improper, excessive, or practices that control the volume and Act grants have been used to control poorly timed application of pesticides, flow rate of runoff water, keep the soil NPS pollution from working farms irrigation water, and fertilizer. in place, and reduce soil transport. and ranches. Also, many programs Pollutants that result from farming and funded by the U.S. Department of Nutrients ranching include sediment, nutrients, Agriculture and by states provide pathogens, pesticides, metals, and salts. cost-share, technical assistance, and Farmers apply nutrients such as Impacts from agricultural activities on economic incentives to implement NPS phosphorus, nitrogen, and potassium surface water and ground water can pollution management practices. Many in the form of chemical fertilizers, be minimized by using management local organizations and individuals have manure, and sludge. They may also practices that are adapted to local come together to help create regional grow legumes and leave crop residues conditions. Many practices designed support networks to adopt technologies to enhance production. When these and practices to eliminate or reduce sources exceed plant needs, or are water quality impacts caused by applied just before it rains, nutrients agricultural activities. can wash into aquatic ecosystems. There they can cause algae blooms, Sedimentation which can ruin swimming and boating opportunities, create foul taste and The most prevalent source of odor in drinking water, and kill fish by agricultural water pollution is soil removing oxygen from the water. High that is washed off fields. Rain water concentrations of nitrate in drinking carries soil particles (sediment) water can cause methemoglobinemia, and dumps them into nearby lakes a potentially fatal disease in infants, or streams. Too much sediment also known as blue baby syndrome. can cloud the water, reducing the To combat nutrient losses, farmers can amount of sunlight that reaches implement nutrient management plans aquatic plants. It can also clog the that help maintain high yields and save gills of fish or smother fish larvae. money on fertilizers. Animal Feeding Operations alternative sources of water and shade, and Pesticides By confining animals in small areas or lots, promote revegetation of ranges, pastures, Insecticides, herbicides, and fungicides farmers and ranchers can efficiently feed and riparian zones. are used to kill agricultural pests. These and maintain livestock. But these confined Irrigation chemicals can enter and contaminate water areas become major sources of animal waste. through direct application, runoff, and An estimated 238,000 working farms and Irrigation water is applied to supplement atmospheric deposition. They can poison ranches in the United States are considered natural precipitation or to protect crops fish and wildlife, contaminate food sources, animal feeding operations, generating against freezing or wilting. Inefficient and destroy the habitat that animals use for about 500 million tons of manure each irrigation can cause water quality problems. protective cover. To reduce contamination year. Runoff from poorly managed facilities In arid areas, for example, where rainwater from pesticides, farmers should use can carry pathogens such as bacteria and does not carry minerals deep into the Integrated Pest Management (IPM) tech- viruses, nutrients, and oxygen-demanding soil, evaporation of irrigation water can niques based on the specific soils, climate, organics and solids that contaminate concentrate salts. Excessive irrigation can pest history, and crop conditions for a shellfishing areas and cause other water affect water quality by causing erosion, particular field. IPM encourages natural quality problems. Ground water can also transporting nutrients, pesticides, and barriers and limits pesticide use and be contaminated by waste seepage. Farmers heavy metals, or decreasing the amount manages necessary applications to minimize and ranchers can limit discharges by storing of water that flows naturally in streams pesticide movement from the field. and managing facility wastewater and and rivers. It can also cause a buildup of runoff with appropriate waste management selenium, a toxic metal that can harm systems. waterfowl reproduction. Farmers can Farm Bill Conservation Funding reduce NPS pollution from irrigation by Livestock Grazing improving water use efficiency. They can In May 2002 President Bush signed the Overgrazing exposes soils, increases measure actual crop needs and apply only Farm Bill, providing up to $13 billion for erosion, encourages invasion by undesirable the amount of water required. Farmers may conservation programs for six years. plants, destroys fish habitat, and may also choose to convert irrigation systems to This Farm Bill represents an 80 percent destroy streambanks and floodplain higher efficiency equipment. increase above current levels of funding vegetation necessary for habitat and water available for conservation programs quality filtration. To reduce the impacts designed to prevent polluted runoff. of grazing on water quality, farmers and For more information, visit www.usda. ranchers can adjust grazing intensity, keep gov/farmbill. livestock out of sensitive areas, provide Related Publications and Web Sites Funding Sources National Management Measures to Control Nonpoint Searchable Catalog of Federal Funding Sources for Source Pollution from Agriculture Watershed Protection epa.gov/nps/agmm epa.gov/watershedfunding This technical guidance and reference document is for use Agricultural Management Assistance Database by state, local, and tribal managers in the implementation of www.nrcs.usda.gov/programs/ama nonpoint source pollution management programs. It contains information on effective, readily available, and economically Clean Water Act Section 319(h) funding (epa.gov/nps/ achievable means of reducing pollution of surface and ground 319hfunds.html) is provided to designated state and tribal agencies water from agriculture. to implement approved nonpoint source management programs. Agricultural Nonpoint Source Pollution Management Environmental Quality Incentives Program (www.nrcs.usda. Web Site gov/programs/eqip) offers financial, technical, and educational epa.gov/nps/agriculture.html assistance to install or implement structural, vegetative, and management practices designed to conserve soil and other natural This web site features a collection of links to helpful documents, resources. federal programs, partnerships and nongovernmental orrganizations that convey advice and assistance to farmers and Conservation Reserve and Conservation Reserve ranchers for protecting water quality. Enhancement Programs (www.fsa.usda.gov/dafp/cepd/default. htm) implemented by the U.S. Department of Agriculture National Agriculture Compliance Assistance Center provide financial incentives to encourage farmers and ranchers to epa.gov/agriculture or call toll-free: 1-888-663-2155 voluntarily protect soil, water, and wildlife resources. EPA’s National Agriculture Compliance Assistance Center is the “first stop” for information about environmental requirements that For More Information affect the agricultural community. U.S. Environmental Protection Agency Nonpoint Source Control Branch (4503T) Animal Feeding Operations (AFO) Web Sites 1200 Pennsylvania Avenue, NW AFO Virtual Information Center: epa.gov/npdes/afovirtualcenter Revised Washington, DC 20460 March 2005 Overview of regulations and helpful links: epa.gov/npdes/afo epa.gov/nps .
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