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Environmental Hazards: Concentrated Animal Feeding Operations (CAFOs) and Public Health

Concentrated Animal Feeding Operations (CAFOs) are agricultural meat, dairy, or egg facilities where animals are kept and raised in confined situations. Feed is brought to the animals rather than the animals grazing or otherwise seeking feed in pastures, fields, or on rangelands. CAFOs concentrate animals, feed, waste (manure and urine), and production operations on a small area of land. In 2012, the U.S. Environmental Protection Agency (US EPA) reported that CAFOs make up approximately 15 percent of total animal feeding operations in the United States.

The US EPA defines CAFOs as livestock operations where the animals are confined for at least 45 days in a 12-month period and have no grass or other vegetation present in the confinement during the normal growing season. In Wisconsin, a CAFO generally means a livestock operation with 1000 animal units. Animal units are based on the weight of the animals.

Managing odors, noise, and waste at CAFOs

The concentrated design of CAFOs can pose many challenges, including how to handle the animal wastes produced by the CAFO, as well as the associated nuisance odors and noise.

If not properly managed, located, and monitored, CAFOs can cause problems both locally and for the surrounding community. Some concerns raised about the potential impacts of CAFOs include: changes in air quality; increased odor and noise complaints; changes in land use; groundwater and surface water quality changes; damage to local roads from increased heavy truck traffic; and impacts on quantity and quality of nearby drinking water wells.

Key messages in the Department of Health Services (DHS) fact sheet

  • The volume and concentration of animal waste produced by CAFOs requires careful planning of environmental, human health, and technological considerations.
  • CAFOs are regulated by federal, state, and local agencies.
  • Best management practices (BMPs) are engineered or agronomic systems to control, treat, or prevent pollution, nuisance, and other problems associated with CAFOs.

For more information on the roles that various Wisconsin state agencies play regarding CAFOs and best management practices, see the DHS fact sheet on CAFOs, P-00977 (PDF) or DATCP's fact sheet on "Understanding Local and State Regulations for New and Expanding Livestock Facilities" (PDF).

Last revised August 12, 2022