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Contact Pacific Southwest Animal Waste

Pacific Southwest, Region 9

Serving: Arizona, California, Hawaii, Nevada, Pacific Islands, Tribal Nations

What is EPA Doing About Animal Waste Management?

Despite tremendous progress since Congress passed the Clean Water Act in 1972, 40 percent of America's waterways remain too polluted for fishing and swimming. Although the Clean Water Act reduced the amount of pollution from factories and sewage, other sources of pollution, such as animal feeding operations (AFOs), continue to degrade our waters, threaten drinking water, and pollute the air.

pie chart of R9's CAFOs

Under the 1998 Clean Water Action Plan, EPA and the U.S. Department of Agriculture (USDA) developed the Unified National Strategy for Animal Feeding Operations. This strategy identifies key steps toward preventing water pollution associated with AFOs. The strategy targets the largest AFOs known as concentrated animal feeding operations (CAFOs) and encourages owners and operators to voluntarily develop Comprehensive Nutrient Management Plans (CNMPs) to prevent water pollution from manure. AFOs are regulated under the Clean Water Act through the National Pollutant Discharge Elimination System (NPDES). AFOs exceeding a population threshold (e.g., more than 700 mature cows) as defined in NPDES regulations are classified as CAFOs. As the result of a February 2005 decision by the United States Second Circuit Court, EPA proposed revisions in June, 2006 to the federal CAFO regulations.

EPA's Pacific Southwest Region is home to more than 4,700 AFOs. Approximately 1,700 of these can be considered CAFOs. EPA has identified dairy waste as the most pressing human health and environmental threat from AFOs in the region. This threat is primarily due to the great quantities of wastewater produced at dairies and recent increases in dairy size (cows per operation).

To comply with milk quality standards, large dairies use tremendous amounts of water to remove manure from their corrals. The sheer volume of wastewater produced at dairies makes them more susceptible to accidentally releasing untreated wastewater into the environment than other types of AFOs.

When combined with the documented human health and environmental impacts associated with animal waste, these factors make dairies a priority for EPA in the Pacific Southwest. Click on a state in the map (right) to learn what EPA and its state partners are doing to protect human health and the environment from animal waste generated by AFOs and CAFOs, particularly dairies.

Related Links

For more information on the regulation of animal waste and its environmental impacts, visit the following Web sites:


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