A recent lawsuit brought about against the EPA has once again pushed large-scale livestock farms into the environmental spotlight. Long counted as a source of waste and fertilizer runoffs, Concentrated Animal Feeding Operations (CAFOs) are regulated under the Clean Water Act and must discharge waste under federal pollution permits. It’s the exceptions to the current regulations that have spurred the most recent lawsuit by Food & Water Watch, an environmental group. 

CAFOs typically hold thousands of hogs, chickens, or cattle, and the potential contaminants in their manure include nitrogen, phosphorous, pathogens, growth hormones, antibiotics, and insecticides. These constituents can be released to waterways from feedlot runoff, leakage/overflow of manure lagoons, and manure applied to cropland. The Gulf of Mexico and Lake Erie’s algae blooms and subsequent waterway hazards and dead zones have been traced to nutrient releases from livestock operations as well as cropland.

The EPA has not revised CAFO regulations since 2008 and in 2021 announced that it would not make changes. Based on the most recent lawsuit, however, “EPA has decided to gather additional information and conduct a detailed study on these issues in order to be able to make an informed decision as to whether to undertake rulemaking,” the agency said. 

CAFOs known to discharge waste are required to file federal pollution permits; only 6,266 CAFOs in the US’s 21,237 CAFOs currently have permits. While the EPA and states work with farm operators to develop practices to mitigate the runoff of these constituents into waterways, in some locations, these practices have been insufficient and have led to listings of impaired waterways and the development of Total Maximum Daily Loads (TMDLs). Food & Water Watch’s lawsuit stresses the exceptions made to the current regulations that allow for, amongst other issues, manure lagoon leaks and spreading waste on frozen ground where it often washes away during rainstorms or thaws.

As part of its rule review process, the EPA will look at current controls and how changing them would result in improved conditions. It will also look into new technologies and best practices that have been identified since its last revision. Per the EPA, any new requirements must be, “technologically available and economically achievable.”

Animal Feeding Operations (AFOs) that meet the regulatory definition of a CAFO are additionally regulated under the National Pollutant Discharge Elimination System (NPDES) permitting program. The NPDES program regulates the discharge of pollutants from point sources to waters of the United States.

Waterborne actively assists our agricultural clients to assess and mitigate pollutant discharges from AFOs and CAFOs through water quality monitoring, geospatial assessments of constituent sources, simulation models, and the development of regional and farm-specific management plans. We have various modeling tools, including APEX, SWAT, and a feedlot runoff module that we developed for the Pesticide Root Zone Model. We use these models to predict constituent runoff from feedlots, cropland, and pasture at the farm-level and watershed-scale and consequently the exposure levels of these constituents in the environment under alternate management practices.  

More information

Animal Feeding Operations (AFOs) | US EPA

Animal Feeding Operations (AFOs) are agricultural operations where animals are kept and raised in confined situations. AFOs that meet the regulatory definition of a concentrated animal feeding operation (CAFO) are regulated under the NPDES permitting program. The NPDES program regulates the discharge of pollutants from point sources to waters of the United States. CAFOs are point sources, as defined by the CWA [Section 502(14)] (PDF)(3 pp, 132 KB, About PDF). To be considered a CAFO, a facility must first be defined as an AFO, and meet the criteria established in the CAFO regulation.

National Pollutant Discharge Elimination System (NPDES) | US EPA

The NPDES permit program addresses water pollution by regulating point sources that discharge pollutants to waters of the United States.  Programs areas include animal feeding operations, aquaculture, industrial wastewater, municipal wastewater, national pretreatment program, pesticide permitting, stormwater, vessel discharges. 

Clean Water Act Section 303(d): Impaired Waters and Total Maximum Daily Loads (TMDLs) | US EPA

Section 303(d) of the Clean Water Act authorizes EPA to assist states, territories and authorized tribes in listing impaired waters and developing Total Maximum Daily Loads (TMDLs) for these waterbodies. A TMDL establishes the maximum amount of a pollutant allowed in a waterbody and serves as the starting point or planning tool for restoring water quality

Animal Feeding Operations |CDC

Pollutants from AFOs can be harmful to human and animal life. They can result in reduced biodiversity and death of fish populations. Nitrogen and phosphorus pollution can contribute to algal blooms which can potentially result in negative health effects in animals and humans. Nitrates, which are transformed from nitrogen in manure or from fertilizers, are the most commonly found contaminant in drinking water wells. Nearly 4.5 million people in the United States are exposed to high levels of nitrates from well sources (1). Microbes that affect animals, such as Cryptosporidium, can also affect humans and cause illness.

Harmful Algal Bloom (HAB) – Associated Illness | CDC 

Harmful algal blooms are the rapid growth of algae or cyanobacteria that can cause harm to people, animals, or the local ecology. Harmful algae or cyanobacteria can look like foam, scum, paint, or mats on the surface of water and can be different colors. These blooms can produce toxins that make people and animals sick. Blooms occur in fresh water, such as lakes and rivers, and salt water, such as oceans or bays.