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Pacific Southwest, Region 9

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

California Animal Waste Management

Regulatory Resources

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California is the nation's number one dairy state. Its 1.4 million dairy cows produced 3.2 billion gallons of milk in 1998, generating 18% of the national supply and over $3.6 billion in sales.

However, these cows generate approximately 30 million tons of manure each year, so proper management of dairy waste on California's 2,700 dairy farms is one of the state's most pressing environmental issues. The California State Water Resources Control Board Exiting EPA (disclaimer) and nine Regional Water Quality Control Boards are responsible for protection of surface and ground water.

The California Agricultural Statistics Service (CASS) tracks county-by-county information on agriculture.

In the 1990s, California's dairy industry experienced significant growth and concentration. In 1993, California's 4000 dairies produced 2.7 billion gallons of milk. Of these dairies, 40% had less than 30 cows. By 1998, the total number of dairies dropped to 2700, yet the state produced 20% more milk. During the same time period, the average number of cows per dairy increased from 367 to 624. The reduction in number of dairies and the increase in milk production and cows per dairy reflect the increasing concentration of dairies and their waste.

California dairies are not only growing in average size, they are also highly concentrated in specific geographic areas. The Central Valley is home to more than 1,600 dairies. The Chino Basin has 300 dairies with more than 325,000 cows in and around a 50-square-mile Dairy Preserve. Considered to be the largest concentration of dairies in the world, the Preserve is adjacent to the Santa Ana River and lies upstream from heavily-populated Orange County. According to the 1997 Census of Agriculture, 8 of the top 11 dairy producing counties in the nation are in these two regions of California: Tulare (1), Merced (2), San Bernadino (3), Stanislaus (4), Riverside (5), Kings (6), San Joaquin (9), and Fresno (11).

Dairies are also located in Marin and Sonoma counties. While the size of the dairies in Marin and Sonoma are small compared to those in Chino and the Central Valley, they are often located on hills that slope toward creeks and streams. These water bodies are vulnerable to manure runoff, especially during the rainy season.

EPA and the State of California work together to use both voluntary compliance assistance and regulatory approaches, as well as demonstration projects to reduce water pollution from California dairies.

Voluntary Approach

This meeting between EPA staff & DQAP stakeholders demonstrates the importance of co-operation to acheive environmental goals
Former Regional Administrator Felicia Marcus addresses Dairy Quality Assurance Partnership stakeholders.

On September 9, 1999, state and federal agencies, the University of California, and the California dairy industry signed a partnership agreement, "Dairy Waste Management: An Integrated Approach to Education and Compliance." The Dairy Quality Assurance Partnership is a collaborative effort to address issues that California dairies face, including environmental regulations and compliance. The Partnership has developed a program to help dairy producers understand environmental regulations and learn ways to prevent surface water and ground water pollution.

The program involves an environmental stewardship certification program. To receive certification, dairy producers attend environmental stewardship workshops, develop stewardship farm management plans, and participate in on-site evaluation of their dairies. As more and more dairy producers voluntarily participate in the Partnership and learn what they can do to protect our environment, EPA is confident that water quality near dairies will improve. This fact sheet summarizes the partnership agreement.

In another voluntary compliance effort, California egg producers are considering participating in an EPA XL (eXcellence in Leadership) project with United Egg Producers.

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Regulatory Approach

EPA also uses its regulatory authority under the Clean Water Act and the Safe Drinking Water Act to prevent animal waste pollution. In California, EPA and state regulatory agencies send inspectors to dairies to determine if they are in compliance with the Clean Water Act, including National Pollutant Discharge Elimination System (NPDES) requirements. Inspectors also assess whether an operation's practices endanger ground water.

EPA and state agencies may issue warning letters/notices of violation, administrative orders to correct violations, and, depending on the violation, administrative penalties with monetary fines. The laws also allow EPA and state agencies to pursue civil or criminal enforcement actions against persons found violating requirements and endangering the health of the public or the environment.

The Northern Valley Central Dairy Waste Task Force, consisting of local, state, and federal agencies led by the U.S. Attorney's Office, has been prosecuting such actions over the past several years.

California's nine Regional Water Quality Control Boards also have authority under state laws to protect ground and surface water from animal waste pollution. Regional Water Quality Control Board 8, which oversees the Chino Basin, is one example. Due to the contamination of the Santa Ana Region's ground water supplies (SWRCB 1988:18), Regional Board 8 developed a general permit restricting dairies from applying their waste to land areas. This fact sheet (29K PDF) summarizes the general permit.

Regional Water Quality Control Board 5, has posted documents and background information addressing animal waste management in California's Central Valley background information home to the largest numbers of CAFOs within EPA Region 9. The site includes explanations of California and federal water quality laws.

Demonstration Projects

In addition to the Partnership Agreement and their enforcement responsibilities, EPA and the regional water boards also sponsor demonstration projects in cooperation with dairy producers. These projects identify best management practices and techniques for addressing the environmental issues faced by California dairies (see example at right).

USDA's Natural Resources Conservation Service (NRCS) sponsors dairy outreach and education projects under the 1996 Farm Bill's Environmental Quality Incentives Program (EQIP). Recent projects included eight that were relevant to California animal feeding operations.

State Links

The following links provide helpful information on state, county and local efforts to manage animal waste effectively:
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