Modern meat production, in which thousands of animals are packed into barns for concentrated feeding operations, has proven to be efficient and profitable, but comes with its own set of problems.
From Washington state to North Carolina, federal lawsuits are challenging the livestock industry to change its ways, basing arguments on studies that increasingly show the impact that phosphorous, nitrates and bacteria from fertilizer and accumulated manure have on lakes and rivers, as well as air pollution that can be harmful to respiratory health.
Livestock farmers insist they're trying to ameliorate the problem by installing grass strips, tilling less and using other techniques to keep manure and fertilizer from draining into waterways.
"I have a general care and concern for the state's water quality and I've personally invested my own dollars to install conservation nutrient retention practices on my farm," said Bill Couser, a fifth-generation Iowa farmer with 5,200 cows. "We realize this is not going to happen overnight or in two years. This could take up to 10 years as this technology comes along."
However, those who rely on rivers and lakes for drinking water or live near the large-scale operations — especially in the top two hog-producing states of Iowa and North Carolina — are growing impatient. Joined by environmental and animal rights groups in a growing number of lawsuits, they're highlighting the debate between the right to raise livestock and the right to clean water and air.
Des Moines' water utility, which serves a half-million people, recently filed a notice of intent to sue farmers in three counties populated by 1.2 million pigs and a million turkeys because it must run water sourced from two central Iowa rivers through a costly system to strip out nitrate, which at levels above a federal limit can reduce the amount of oxygen carried in the blood of children younger than 6.
A federal judge in eastern Washington ruled last month that an industrial dairy farm's manure management practices posed an "imminent and substantial endangerment" to the environment and thousands in the lower Yakima Valley who rely on well water. And on Jan. 28, a coalition of groups sued the EPA for what they said is a failure to address air pollution from cattle, hog and poultry farms in California, Wisconsin and Iowa.
"Pork is cheap and cheap to produce in large factories because they don't pay for cleaning up the Des Moines water supply and they don't pay for the asthma neighbors get, they don't pay for polluting downstream water that used to be potable and they don't pay for the loss of property values," said Steve Wing, a University of North Carolina at Chapel Hill epidemiologist.
About 68 percent of the nation's lakes, reservoirs and ponds and more than half of its rivers and streams are impaired, the U.S. Environmental Protection Agency says, meaning they don't meet one or more water-quality standards and are considered too polluted for the intended use. The main culprit: agriculture, including poorly located or poorly managed animal-feeding operations and misapplication of chemicals and fertilizer, EPA reports show.
The hog industry's shift from small family farms to large-scale farms is dramatic, going from more than 200,000 in the early 1990s to just over 21,600 in 2012.
A driving force behind some of the large-scale hog farms is Murphy-Brown LLC, which became part of the world's largest pork producer when China-based WH Group bought corporate parent Smithfield Foods in 2013. WH Group aims to feed China's appetite for meat with cheaper hogs from the United States, and that foreshadows increased production in the U.S., according to lawsuits filed in eastern North Carolina.
The water- and air-quality lawsuits are mostly driven by advocates of locally grown food as well as animal-rights and environmental activists. But in some cases, farmers are going after farmers.
Barb Kalbach has fought for more than a decade against the construction of huge hog operations, and joined a statewide nonprofit that argues such enterprises are ruining Iowa's waterways.
Pork is a $7 billion industry in Iowa, which is the nation's largest pork producer with about 21 million pigs — seven times the number of human residents — that create about 9 billion gallons of manure annually.
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"I have in the back of my mind this idea that we have thousands of miles of clean water, which is a gift in this state and we just throw manure in it," the 64-year-old said. She and her husband, who live about 40 miles west of Des Moines, once raised a few hogs, cattle and sheep, but quit primarily because it's difficult to compete with large-scale operations that have corporate meatpacking contracts.
About 200 miles north, Matt Schuiteman raises about 3,000 hogs plus some cattle. Since 2008, the 40-year-old farmer has worked with the city of Sioux Center, Dordt College and others to research how to keep nitrogen on the farmland and out of waterways.
Farmers care about the environment and are willing to work on improvements that will minimize impact, he said, adding that lawsuits aren't the course of action.
"Maybe we can all get to where we want to be together instead of drawing the battle lines ... You want to force some action but there are ways to do it and ways that don't work," he said.
In North Carolina, 10 million hogs produce as much fecal waste in a day as 100 million people, much of it stored in ponds as large as three football fields. The treated, liquefied manure and urine is then pumped to large sprinkler systems and flung on fields for fertilizer.
For people like Richard Brown, whose trailer is surrounded on three sides by fields that soak up effluent from 2,500 nearby hogs, the smell is a daily drag.
"It just stinks like the devil," said Brown, who lives in Duplin County — the nation's top county for hog production, according to the U.S. Agriculture Department's 2012 census.
Brown is one of about 500 who've joined the federal lawsuits against Murphy-Brown, alleging the farms deprive them of enjoying their property because of the strong odor — complaints first raised two decades ago that plaintiffs say have gone unanswered by legislators and regulators.
Gases and air particles from the manure affect residents' mental and physical health, Wing says, including breathing difficulty, sore throat, nausea, eye irritations and high blood pressure.
The putrid liquid rains down on 66-year-old Elsie Herring's property in nearby Wallace, and the odor makes her cough and her eyes burn. "Whenever they start spraying, we're held prisoners inside. ... If you're outside it will blow down on you," she said.
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Murphy-Brown encourages residents to express concerns about operations, but only a handful do in any given year, the company said in a statement. "We take these complaints seriously and seek swift resolution as part of our environmental management system," the company said. "We have a vested interest in the health and well-being of these communities and we work to maintain positive relationships with our neighbors."
The choice, according to Iowa State University economist Catherine King, may come down to consumers: Does the public pay to remove contaminants or shell out more for meat?
"We don't know how to produce food and fuel from this incredibly rich land without having nitrogen and nutrient pollution, so society has to figure out what balance it wants," Kling said. "Society needs to be engaged in a conversation about what trade-offs we are willing to make and who is going to bear the cost."