The nature of water pollutants has changed in recent decades, but regulators have not kept pace, and the public and the environment are vulnerable to new kinds of contamination.
In contrast to the obvious “point-source” pollutants of last century—the classic industrial pipe spewing brown filth into pristine waterways such as Newtown Creek or the Housatonic River—the greatest source of water pollution today is the more diffuse “nonpoint-source” pollution known as storm-water runoff. This term describes pollutants of many kinds, from many sources—motor oil, paint, sewage, fertilizers, insecticides, pharmaceuticals, and other contaminants—that are washed off the land by rain, snow, or mist and into water supplies.
This represents a reversal. In 1970, the EPA estimated that 85 percent of water pollution came from obvious point sources, such as factories or wastewater treatment plants; only 15 percent came from nonpoint sources, such as poultry farms, suburban lawns, or city streets. By 2010, point-source pollution had been significantly reduced, thanks largely to the Clean Water Act (CWA). Now point-source pollution accounts for only 15 percent of water contamination, while nonpoint sources account for 85 percent.
But EPA regulations have not adapted to this shift. The traditional top-down regulations of the CWA are not well suited to control runoff across a watershed. Storm-water runoff is especially difficult to identify and remediate because it is so diffuse, washes across wide swaths of landscape, and pollutes water in myriad ways. This holds as true for rural citizens who draw water from a single well as it does for urban dwellers who rely on vast systems of pipes, pumps, and reservoirs.
It was long assumed that well water was better protected from contamination than surface water. But that is not always the case. Ninety-six percent of all health violations occur at small water systems, according to the EPA, and those who use private wells are most vulnerable to contamination.
While wells are relatively cheap to build, they can be polluted by impurities, such as bacteria, viruses, parasites, fungi, fertilizers, volatile organic compounds (such as methane or formaldehyde), and naturally occurring arsenic or uranium. Frequently they are polluted by agricultural runoff, such as manure, pesticides, and nutrients.
Approximately 43 million Americans—15 percent of the population—get their drinking water from “self-supplied sources,” which usually means wells. But the Safe Drinking Water Act does not protect wells that serve twenty-five or fewer people; in those cases, homeowners are responsible for the quality of their own water (and should test it). The quality of that water depends on what is happening around the well, which homeowners cannot always control.
In February 2004, just after Samantha Treml turned six months old, her doctor suggested that her parents, Scott and Judy Treml, test their well water. The Tremls live in a rural area near the town of Luxemburg, about fifteen miles east of Green Bay, Wisconsin. Using a testing kit, they sent a sample to a state lab. A few days later they received the results: the water was free of harmful bacteria and chemicals, and perfectly safe for Samantha to drink.
Three weeks later, on the evening of February 22, Glen Stahl, who runs a large feedlot nearby, with about nine hundred cows—a so-called CAFO, or concentrated animal feeding operation—began to spread liquid manure on the field across the road from the Tremls’ house. Stahl wasn’t spreading the manure as fertilizer; his large storage pits had filled to nearly overflowing, and he was spreading the manure simply to get rid of it. At the time, this was a common and legal practice.
That day, eighteen inches of snow lay on the ground, but the temperature had risen to forty degrees and the snow was melting. As the snow melted into water, it carried Stahl’s manure into a ditch, where it pooled and seeped through cracks in the bedrock into the groundwater, which flowed west, toward the Tremls’ well. When Scott Treml asked Stahl to stop spreading manure, the farmer cursed and said he had permission to spread from the Wisconsin Department of Natural Resources (WDNR), the state environmental regulatory agency. Stahl continued to spray for three days, eventually coating the field with eighty thousand gallons of liquid feces.
On February 29, Judy Treml filled her bathtub for six-month-old Samantha; the water looked clear and was odorless. The following evening Judy turned on her kitchen tap. Instead of clear water, a thick brown liquid that smelled of fresh cow dung sputtered out. Repulsed, she jumped back and asked her husband to call the WDNR.
“Judy, I already tried,” he said. “They don’t care.”
Scott had called David Bougie, the WDNR enforcement agent responsible for Stahl Farms. Bougie visited the field across from Treml’s house and judged that there was no evidence of manure runoff. Calling other DNR officers, Scott was told by one, “I’m a very busy man … call someone else,” and by another, “If you think that’s bad, I’ve actually seen straw coming out of someone’s kitchen tap.” At a public meeting, Bougie would say only, “Glen Stahl’s spreading met the conditions of his permit” and refused to take regulatory action. Feeling “utterly helpless,” the Tremls walked away. Just then, a man who worked for the local government pulled them into his office and showed them a map of the field Stahl had sprayed. A shallow, fractured bedrock, known as karst, lay just beneath the surface of much of the field. Karst is porous and allows water, and the things it carries, to seep underground. State guidelines now restrict the spreading of manure on fields overlying karst.
On March 5, Scott Treml opened the door to Samantha’s room to discover that the baby’s hair, face, ears, body, and crib were coated in vomit and diarrhea. By the following evening, Samantha was growing listless, and the Tremls rushed her to the emergency room. The ER doctor judged that Samantha had been infected by E. coli from her Sunday-night bathwater.
E. coli is the common abbreviation for Escherichia coli, a rod-shaped bacterium that originates in the lower intestines of warm-blooded organisms. It is transmitted by animal or human feces. Some strains of E. coli can be beneficial to the host, but virulent forms, such as the O157:H7 strain, can cause painful cramps, diarrhea, kidney failure, or even death. Coliforms are a family of bacteria including E. coli; they are also associated with animal or human excrement and cause gastroenteritis. According to the EPA, the safe limit for both E. coli and other coliforms is zero. In Wisconsin, E. coli bacteria present in water at 1,000 parts per milliliter are sufficient to close a public beach. The manure flowing from the Tremls’ tap had an E. coli count of 2,800 parts per milliliter and coliform at 9,800 parts per milliliter. Tests of the Tremls’ well by the state hygiene labs confirmed that the water was contaminated by both E. coli and other coliform bacteria (which can be present even in clean-looking water).
“I was devastated,” Judy recalled. “I had unwittingly exposed my baby to E. coli because I didn’t have any knowledge that manure applied to the land could contaminate our drinking water.”
In the hospital, the doctor explained that Samantha faced four possible outcomes: she could be sick for a few days, then recover; she could suffer kidney damage, then recover; she could suffer permanent kidney damage, which would require a transplant; or she could die.
As Judy Treml considered this, she suddenly felt woozy and was admitted to the ER, infected by the same bacteria that had sickened her daughter. At home, her two older daughters and Scott had also been stricken.
Every member of the Treml family eventually recovered, but in April 2004, with the help of Midwest Environmental Advocates, Wisconsin’s only pro bono environmental law firm, they filed a notice of their intent to sue Stahl Farms for violating the Clean Water Act. The state Department of Justice also filed suit against Stahl, who had allowed manure to leak from his feedlot for twenty years while receiving more than $10,000 in state assistance to prevent environmental pollution. In January 2006, a US federal court judge approved a settlement under which Stahl’s insurance company paid the Tremls $80,000 in damages. Stahl agreed not to spread manure on the field across from the Tremls’ house from December through March, the period of highest risk for groundwater contamination.
Testifying before Congress about water quality in the fall of 2009, Judy Treml asked, “What’s it going to take for the WDNR to enforce the Clean Water Act? I hope for our state that a death, or several deaths, isn’t what it takes!”
Regulating and stopping agricultural runoff is not easy. In tight-knit farm communities, confronting neighbors is socially awkward. State regulators are torn between maintaining water quality and being sensitive to farmers, who provide food, jobs, and community leadership, while Congress has allowed large farms to “self-police,” a rule that has proven ineffective.
Most farmers care deeply about the land and do not intentionally pollute. But, according to the EPA, agricultural runoff is now the single biggest source of water pollution in America. Pathogens such as E. coli are responsible for 35 percent of the nation’s impaired waterways, and large “factory farms” are one of the most common sources of pathogens.
An estimated 19.5 million Americans are sickened each year from waterborne bacteria, viruses, or parasites, including those from animal and human sewage, according to a 2008 study by the scientific journal Reviews of Environmental Contamination and Toxicology.
In the United States, farmed animals produce more than 1 billion tons of manure per year. As the population, and its demand for food, continues to rise, the amount of cow, pig, goat, and poultry excrement continues to grow and to infiltrate water supplies.
The problem is not limited to Wisconsin. The Chesapeake Bay and the Gulf of Mexico—two of the most ecologically rich aquasystems in the world—have been badly contaminated by agricultural runoff. In California, up to 15 percent of wells in farming regions have water pollution above federal thresholds. In Arkansas, Maryland, and Oklahoma, residents and regulators have charged that poultry farmers have polluted important drinking supplies. Runoff from dairies and farms had such a devastating effect on Lake Okeechobee and the Everglades that the South Florida Water Management District has spent $2 billion to build forty-five thousand acres of “filter marshes” to remove some of the phosphorus flowing into the water.
Under the ideal cycle, manure is used to fertilize crops, which are in turn used to feed the cows. This was the traditional, holistic model used on small family farms. But the number of small family farms has steadily declined since the Second World War—as of 2002, only 25 percent of US farms were considered family farms—while the number of CAFOs has steadily risen, due largely to their economies of scale.
Farming is a significant industry. In 2008, US farms held 96 million head of cattle, 68 million pigs, 9 billion broiler chickens, and 446 million laying hens. Cattle farming was a $48.6 billion business, while milk production was valued at $34.8 billion, broiler production at $23.1 billion, and poultry egg production at $8.2 billion. The incentive to expand these profit centers is large, but they have a significant health and environmental cost.
Cows are relentless eaters, and a cow’s digestive system, with its series of four stomachs, produces a steady stream of manure. Dairy cows are often fed a high-protein diet, which increases milk production and results in liquid manure that is easier to spray than solid manure. A single lactating Holstein emits 150 pounds of waste every day—usually two-thirds wet manure and one-third urine. This is equivalent to the daily waste of eighteen people. A large farm with four thousand cows will produce some 200 million pounds of manure a year.
Wisconsin had 19 CAFOs in 1992; by 2009, the number had leaped to 185, and the WDNR had 50 new applications under review. In January 2010, state regulators green-lit Wisconsin’s biggest CAFO yet: Rosendale Dairy, a $70 million operation that will house eight thousand cows and produce 92 million gallons of manure a year—which is more biological waste than every city in the state other than Madison and Milwaukee produce in a year.
The largest dairy in the world is Threemile Canyon Farms, a few miles from the Columbia River, near Boardman, Oregon. The farm promotes itself as “sustainable” and “green” and claims it contains forty-one thousand head of cattle, though news reports say the farm contains fifty-five thousand cows and is permitted to contain ninety thousand. This industrial-scale operation is jointly owned by A. J. Bos, of Bakersfield, California, who runs one of the largest dairy operations in the country, and R. D. Offutt, of Fargo, North Dakota, one of the largest potato growers in the United States. Threemile Canyon produces an estimated half a million tons of manure per year.
At times, CAFOs produce so much liquid manure that it overwhelms a farmer’s ability to store it; in that case, he will usually spread it on fields to get rid of it. Not infrequently, this excess manure is washed off the land by precipitation. Glen Stahl apparently faced this situation when he sprayed eighty thousand gallons of liquid cattle feces on the field next to the Tremls’ house.
Aside from pathogens such as E. coli, manure also contains nutrients, such as phosphorus and nitrogen, that, in excess, can create havoc in the ecosystem. Phosphorus is a common supplement used to stimulate milk production; but many farmers add more phosphorus than necessary, just to “make sure” their cows lactate productively. Nitrogen originates in cattle feed, such as distillers’ grains, the waste let over from corn fermentation, which supplies dairy cows with protein. (Distillers’ grains cause cows to produce greenhouse gases—including ammonia, methane, and other volatile compounds—which has stirred a debate over agricultural air pollution.) Cattle in the United States excrete some 3 million pounds of phosphorus and 8 million pounds of nitrogen a day.
When manure is spread on fields, crops absorb some of these nutrients, but the majority is washed off the land into waterways. This can cause human health problems, such as cyanosis, in which the hemoglobin in blood is deoxygenated (commonly known as the blue baby syndrome, because tissues low on oxygen fill with dark, deoxygenated blood, which gives the skin a blue cast). Moreover, excess nutrient flows in agricultural regions—from the Great Lakes to the Sacramento Delta—have caused vast algal blooms, which block sunlight and absorb oxygen, creating lifeless underwater deserts known as dead zones.
While researchers look for new ways to use manure, such as converting it into gas to produce electricity (Threemile Canyon has built a pilot manure “digester” that traps methane gas for use as fuel), water experts say the best way to reduce agricultural runoff is to strengthen pollution laws and empower regulators to enforce them. As the law stands now, the EPA cannot shut down a farm or block it from expanding, even when its manure runoff threatens water supplies.
Despite its known hazards, agricultural runoff is poorly regulated. The Clean Water Act is focused on the quality of water in pipes and ditches and does not address more complex scenarios, such as when manure sprayed onto a field seeps into groundwater. This type of nonpoint-source pollution is governed by state laws, which are often weak or not well enforced. What’s more, many farmers do not file the requisite paperwork and are rarely fined for polluting water. Under President George W. Bush, regulations were loosened to allow farms to “self-certify” that they would not pollute; many experts were not surprised when this resulted in an increase in agricultural runoff.
The EPA has instituted special rules to regulate runoff from the thousands of large CAFOs (defined by the EPA as a farm that keeps more than 700 dairy cows, 1,000 cattle, 2,500 swine, 55,000 turkeys, or between 30,000 and 125,000 chickens) that are cropping up across the country. Yet those rules have done little to stem the tide of manure that is infiltrating water supplies.
Moreover, the agricultural lobby has blocked efforts to regulate runoff that causes water pollution. In Brown County, Wisconsin, for example, officials instituted new rules to limit dairy operations and prohibit the spraying of manure during high-runoff months. But farm lobbyists inserted a provision requiring the state to finance up to 70 percent of the cost for some farms to follow the regulations, which made the program prohibitively expensive.
Other nations have grappled with these issues, and some have pioneered tough regulation. Holland instituted policies in the 1980s to limit the size of livestock farms, capping the amount of manure allowed per hectare; if a Dutch farmer wants to produce more manure than his allotment, he must buy more land to accommodate extra cows. While such an approach could theoretically work in the United States, in practice the agricultural lobby would certainly oppose it.
In the 1970s, Congress identified CAFOs as polluters to be regulated under the Clean Water Act. But the biggest facilities were able to avoid government regulation by claiming they do not discharge pollutants into waterways protected by the CWA. Incensed, a coalition of environmental groups sued the EPA in 2009 to force regulators to monitor the effects of factory farms on waterways more closely. Gathering more—and higher-quality—data, the environmentalists hope, will eventually lead to tougher regulations and better water protection. The EPA has settled the suit and committed to finalizing new rules by 2012.
Urban dwellers hear of these battles over manure and assume that they don’t affect them; after all, they don’t draw water from wells, don’t live next to CAFOs, and don’t understand how agricultural runoff could possibly impact their water supplies. But it does.
When she testified about water pollution before Congress in 2009, Judy Treml pointed out that Stahl’s manure runoff was not simply her problem: the creek he polluted flows into the Kewaunee River, which supplies Lake Michigan, the third largest of the Great Lakes. Twelve million people live along the shores of the lake, including in major cities such as Milwaukee and Chicago. Lake Michigan was badly polluted during the Industrial Age but has recently been the focus of intensive cleanup efforts. This has put the states around it—Wisconsin, Illinois, Indiana, and Michigan—in an ironic predicament: while they have made costly and largely successful efforts to clean up the lake, they have simultaneously provided incentives for farms to grow, which creates more agricultural runoff.
“It makes no sense to clean up a lake only to have all the water that drains into it polluted,” Treml told Congress. She added that as a homeowner, a taxpayer, and a mother, she was astounded by the lack of regulation for agricultural runoff: “It’s not a matter of convenience,” she said. “We need water to survive.”
Cities face another set of runoff problems even more daunting than those faced by rural communities. With much of their surface area paved, cities do not absorb precipitation well. The thousands of pipes, valves, and pumps of city sewers are often old, leaky, and overwhelmed, especially during an intense storm burst or a prolonged rain. Furthermore, the demand on city systems to separate water from human and industrial effluent is much higher than on rural systems. Sewage treatment requires enormous amounts of energy, which is costly and adds to climate change—which ultimately creates more runoff. Most of the nation’s sewer network was built in the nineteenth and twentieth centuries and has been compared to a ruptured appendix—an overburdened system that is struggling to function and remain clean.