Does the manure generated by large dairy farms cause significant water pollution?
General Reference (not clearly pro or con)
[Editor's Note:Animal feeding operations (AFOs) and confined animal feeding operations (CAFOs) are animal farming operations where dairy cows (and other livestock aimals) are housed. Animals in AFOs and CAFOs are fed on site rather than being allowed to graze or otherwise find food in pastures, fields, or on rangeland. There are approximately 450,000 AFOs in the United States.
Peter Lane Taylor, a writer and TV producer, stated in his article "Florida Dairy Farms and Springs Protection: Got Solutions?," published on www.floridasprings.org (accessed June 17, 2008):
"Cows are prolific producers of manure and urine. In an average day of grazing, milking, and just mooing about, one dairy cow can generate over 100 pounds of manure and urine...
In areas and facilities where cows are milked, fed, and staged between the various phases of the milking process, wastes are removed through pressure-washing, and in some cases, even bulldozing. Once flushed from these facilities, the wastes - now a semi-solid sludge - are directed into holding ponds to await their final disposal through one of two techniques.
In the first of these techniques, the mixture is spread in a thin layer over a large field by truck so that the nutrients can be absorbed as fertilizer by a variety of nitrogen absorbing plants like alfalfa and other grasses. In the second, cow manure mixture is further diluted with water and sprayed over a large area by a center-pivot irrigation system. In reality, neither of the techniques is full proof; a percentage of the nutrients bypasses the root system and enters the underground aquifer."
The Congressional Research Service wrote in its Sep. 20, 2006 report "Animal Waste and Water Quality: EPA's Response to the Waterkeeper Alliance Court Decision on Regulation of CAFOs," that:
"The primary pollutants associated with animal wastes are nutrients (particularly nitrogen and phosphorus), organic matter, solids, pathogens, and odorous/volatile compounds. Animal waste also contains salts and trace elements, and to a lesser extent, antibiotics, pesticides, and hormones. Pollutants in animal waste can impact waters through several possible pathways, including surface runoff and erosion, direct discharges to surface waters, spills and other dry-weather discharges, leaching into soil and groundwater...
Although agricultural activities are generally not subject to requirements of environmental law, discharges of waste from large concentrated animal feeding operations (CAFOs) into the nation's waters are regulated under the Clean Water Act (CWA)."
The California Farm Bureau Federation wrote in its article "How Much Water Does It Take to Make a Glass of Milk?," published on www.cfbf.com (accessed Aug. 20, 2009):
"When you add together the amounts of water needed to provide food and water for the cows, to keep the dairy barns clean, and to process the milk, it takes 48.3 gallons of water to produce one eight-ounce glass of milk."
Does the manure generated by large dairy farms cause significant water pollution?
The US Environmental Protection Agency provided the following testimony on Sep. 6, 2007 during the Senate Environmental and Public Works Committee hearing "An Examination of the Potential Human Health, Water Quality and Other Impacts of the Confined Animal Feeding Operations Industry":
"AFOs [animal feeding operations] annually produce more
than 500 million tons of animal manure...
An ongoing trend toward fewer but larger farm operations,
together with greater emphasis on intensive production methods, increases
environmental and public health risks by concentrating more manure nutrients and
other animal waste impacts within smaller geographic areas. In addition, many
large operations do not have sufficient land to effectively use the manure they
generate as fertilizer. Animal waste and wastewater can enter water bodies from
spills or breaks of waste storage structures (due to accidents or excessive
rain), and over-application of manure to crop land…
Improperly managed manure has caused acute and chronic water
quality problems and is a significant component of water body impairments.
Manure and wastewater from CAFOs can contribute pollutants such as excessive
amounts of nitrogen and phosphorus, organic matter, sediments, pathogens, heavy
metals, hormones, and antibiotics to the environment."
People for the Ethical Treatment of Animals (PETA) published the following information on the homepage of its website, www.milksucks.com (accessed May, 20 2008):
"[N]ot only is milk a waste of energy and water, the production
of milk is also a disastrous source of water pollution. A dairy cow produces 120
pounds of waste every day -- equal to that of two dozen people, but with no
toilets, sewers, or treatment plants.
In Lancaster County, Pa., manure from dairy cows is destroying
the Chesapeake Bay, and in California, which produces one-fifth of the country's
total supply of milk, the manure from dairy farms has poisoned vast expanses of
underground water, rivers, and streams. In the Central Valley of California, the
cows produce as much excrement as a city of 21 million people, and even a
smallish farm of 200 cows will produce as much nitrogen as in the sewage from a
community of 5,000 to 10,000 people, according to a U.S. Senate report on animal
[Editor's Note: A 1998
EPA study showed that US dairy cows produced 54 billion pounds of manure (553KB)- 2.6 times the amount produced by the
The Pew Charitable Trusts' Commission on Industrial Farm Animal Production wrote in its Apr. 28, 2008 report "Putting Meat on the Table: Industrial Farm Animal Production in America," that:
"Application of untreated animal waste on cropland can
contribute to excessive nutrient loading, contaminate surface waters, and
stimulate bacteria and algal growth…
Beyond nitrogen and phosphorus, waterborne chemical
contaminants associated with ifap [industrial farm animal production]
facilities include pesticides, heavy metals, and antibiotics and hormones…
It is also recognized that ammonia emissions from livestock
contribute significantly to the eutrophication and acidification of soils and
The large concentration of animals on the typical industrial
farm presents a major waste management problem. The volumes of manure are so
large that traditional land disposal methods can be impractical and
environmentally threatening. Excess nutrients in manure contaminate surface and
groundwater resources. Today, over a million people are estimated to take their
drinking water from groundwater that shows moderate or severe contamination with
nitrogen-containing pollutants mostly due to the heavy use of agricultural
fertilizers and high rates of application of animal waste."
The Association of Metropolitan Water Agencies provided the following testimony on Sep. 6, 2007 before the United States Senate Committee on Environment and Public Works Hearing, "An Examination of the Potential Human Health, Water Quality, and Other Impacts of the Confined Animal Feeding Operation Industry":
"[C]oncentrated animal feeding operations [CAFOs] are
very different from small family farms…a CAFO is a large farm that generally
holds more than 700 dairy cattle…
[T]he typical manure disposal practices of CAFOs - which
commonly involve holding waste in huge leak-prone cesspools and field
application techniques that lead to increased runoff - pose serious dangers to
the quality of nearby drinking water supplies. Waste from family farms, on the
other hand, is usually generated and released in much smaller volumes, so it is
more readily controlled.
As the number of CAFOs in the United States continues to grow,
industry representatives have increasingly argued that they deserve an exemption
from pollution cleanup liability under CERCLA. Legislation has
been introduced in both houses of Congress that would specifically exclude
manure and its components from the law's definition of a 'hazardous substance'
under section 101(14) and from the definition of a 'pollutant or contaminant'
under section 101(33)…
For a number of years there have been cases of components of
untreated manure from CAFOs having harmful effects on public drinking water
supplies across the country…
[In one specific example] Dairy cows in CAFOs upstream
from Lake Waco created 5.7 million pounds of manure per day that was
over-applied to land and made its way into the lake. The state found that nearly
90% of the controllable phosphorus in the river came from CAFOs in the
watershed, and an independent researcher who conducted much of the state's
analysis found that dairy waste applied to fields supplied up to 44% of the
lake's phosphorus. From 1995 to 2005, the city spent $3.5 million on
phosphorus-related water pollution, and has spent a total of approximately $70
million to improve water treatment. To recoup costs the city filed suit against
14 large industrial dairies in 2003 and eventually reached a settlement with the
The American Farm Bureau Federation stated the following in a Sep. 6, 2007 statement, presented by Chris Chinn, to the Senate Committee on Environment and Public Works:
"Many people outside of agriculture and the livestock industry
have concerns about the environmental and health impacts of livestock
operations. Some have gone so far as to demonize livestock operations, calling
them factory farms and industrial livestock production…
It is often overlooked, but the vast majority of farmers who
operate CAFOs are involved in a family-based business, are highly educated
college graduates, community leaders, and experts in science and technology.
Most are trained in humane animal husbandry and environmental sciences and spend
great amounts of time, money and other resources ensuring that their operations
do not harm the environment…
CAFOs are regulated by the Clean Water Act. They must either
have zero discharges, or obtain a National Pollutant Discharge Elimination
System (NPDES) permit. Contrary to the assertions of some, it would be incorrect
to presume that all or even most CAFOs experience actual discharges to navigable
In particular, we note that any animal feeding operation (pork,
poultry, beef, dairy or horse) of almost any size faces potential enforcement
and severe penalties for even a single discharge from the operation to waters of
the United States…
Farmers and ranchers understand their roles in improving and
maintaining the health and safety of the nations' environmental resources.
Farmers are sensitive to the environment because they own and manage two-thirds
of the nation's land. They are doing their part to promote the principles of
environmental stewardship by being good caretakers of the nation's soil, air and
Dairy Farming Today, an organization that provides information about dairy production, stated the following in their "Being Green" article, posted on www.dairyfarmingtoday.org (accessed June 6, 2008):
"Dairy cows need to drink plenty of clean water to stay healthy
and produce quality milk, so farmers take water protection and conservation
The proper recycling of cow manure plays a central role in
protecting nearby lakes, rivers and streams. Farmers store manure and spread it
on their crop fields according to a Nutrient Management Plan that takes into
account the types of soil found on the farm, the terrain of the fields and the
amount of nutrients needed by the crops. Other water protection measures include
building fences along streams and planting trees along rivers."
Larry Serpa, Director of Member Relations and Milk Procurement for Land O'Lakes Dairy Foods, wrote in his Nov. 3-4, 2001 article "Dairies Can Coexist with Environment," published in the Visalia Times-Delta, that:
"We cannot allow…environmentalists to dictate their 'no impact
- no growth' mentality in our rural communities. Everything we do from driving a
car to a weekend backyard barbecue has some impact on the environment...
Local dairy farmers are doing their part...to minimize and
eliminate environmental impacts…
[P]lans call for storing waste more carefully to eliminate
runoff, and leaving sufficient land available for the safe field applications to
manure. At modern dairies, manure isn't waste at all - it's a vital crop
nutrient, used safely and efficiently to grow the feed crops necessary to
support the dairy…
No one wants to degrade the land, especially not the families
who live and work on their dairies."
[Editor's Note: In our effort to find additional "con" statements to the question we spent many hours researching online, and were unable to find suitable "con" responses.
We also directly contacted three major dairy industry organizations involved with environmental research. On June 12, 2008 we emailed the Community Alliance for Responsible Environmental Stewardship (CARES) and made a follow up telephone call a few days later. On June 13, 2008 we emailed the National Milk Producers Federation (NMPF) and made a follow up call the subsequent week. On June 17, 2008 we emailed Paul Martin, the Director of Environmental Services for the Western United Dairymen, and made two follow up telephone calls to his office.
As of July 3, 2008, none of these organizations have yet provided us with their response.]