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This Series

Our Water Watch Wisconsin project examines water quality and supply issues. This series, Failure at the Faucet, investigates threats to drinking water across Wisconsin.
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Going organic: One farmer’s fight against contaminants in the groundwater

Cost of most drinking water pollution borne by consumers

What is nitrate?

Safeguarding your drinking water: What you can do

What’s in your water? Bridgit Bowden, investigative reporting fellow for the Wisconsin Center for Investigative Journalism and Wisconsin Public Radio, explains how nitrate pollutes drinking water in a video for Harvest Public Media.
On the Radio

Investigative reporting fellow Bridgit Bowden reports on the extent of nitrate pollution for Wisconsin Public Radio and the Wisconsin Center for Investigative Journalism.

Born a month early in the spring of 1999, Case 8 had been thriving on formula. But at three weeks old, when her family ran out of bottled water and started using boiled water from the household well at the dairy farm where they lived, she got sick.

She was just 4 pounds, 10 ounces, when her parents brought her to a Grant County emergency room. Cold, pale and “extremely blue,” she was rushed by helicopter to a regional intensive care unit.

Nearly all of her red blood cells had lost the ability to carry oxygen, according to medical records Wisconsin public health officials summarized in the Wisconsin Medical Journal.

Two days after she fell ill with methaemoglobinaemia, or “blue baby syndrome,” water tests turned up the most likely culprit — high levels of nitrate.

According to state estimates, nitrate is at unsafe levels in an estimated 94,000 Wisconsin households. One in five wells in heavily agricultural areas is now too polluted with nitrate for safe drinking, according to data from the state Department of Agriculture, Trade and Consumer Protection.

And public water systems recorded 57 violations of health-based standards for nitrate in 2014. Those systems were required to post notices, provide bottled water, replace wells, install treatment or take other corrective actions to reduce nitrate. More than 120 of the 11,420 systems failed either to monitor or report nitrate levels.

“Nitrate that approaches and exceeds unsafe levels in drinking water is one of the top drinking water contaminants in Wisconsin, posing an acute risk to infants and women who are pregnant, a possible risk to the developing fetus during very early stages of pregnancy, and a chronic risk of serious disease in adults,” according to the 2015 Wisconsin Groundwater Coordinating Council report to the Legislature.

The multi-agency council also reported that nitrate — one of the most pervasive groundwater contaminants in Wisconsin — is “increasing in extent and severity.”

Despite the signs of trouble, Wisconsin’s most recent in-depth look at blue baby syndrome is more than a decade old.

State health officials identified eight cases in the 1990s. All recovered — including Case 8, who was released from the hospital after 17 days. Generally, a baby can recover in one or two days once given clean water.

New studies have suggested even the current health standard for nitrate may be too high.

Yet blue baby syndrome is rare. That is probably because private well owners have been warned for decades to test their water, especially if they have a baby. But over the past four decades, the contamination has been worsening in extent and severity.

Katie Kowalsky / Wisconsin Center for Investigative Journalism

Among those with water contaminated by nitrate are Sherryl and Doug Jones of rural Spring Green.

About eight years ago, water from their private well tested at 20 milligrams of nitrate per liter of water — twice the health limit. Sherryl Jones said the couple initially switched to bottled water and, since 2012, they have been using a reverse osmosis system to remove nitrate at a cost of about $25 a month. Reverse osmosis removes nitrate and other contaminants by using high pressure to push water through a semipermeable membrane.

“We had children, we had babies in our house, we had a pregnant daughter, we had pregnant daughters-in-law. What was this (water) doing? There was no way we could let them drink this water,” Sherryl Jones recalled.

Jones said she urged neighbors to get their water tested, too. The result: Some of them had been drinking water with four times the health limit of nitrate. In fact, testing by the University of Wisconsin-Stevens Point’s Center for Watershed Science and Education found 31 percent of the private well samples collected in the Spring Green area had nitrate levels above the health standard.

Sherryl Jones said the DNR never warned them about high nitrate levels in the beautiful area along the Wisconsin River where they built their dream home. State officials have been studying dangerous nitrate levels private water wells in the Lower Wisconsin River Valley at least since the early 1990s.

Ian Torkelson runs a test for the presence of nitrate and phosphorous in water at the University of Wisconsin-Stevens Point’s Center for Watershed Science and Education. Nitrate from fertilizers, including animal manure, and human waste has polluted numerous wells in Wisconsin. Debra Sisk / University of Wisconsin-Stevens Point

“They’ve known about it. Now, what have they done?” she said. “They haven’t even educated the residents of this area.”

Rules no match for nitrate

At least 90 percent of nitrate inputs into groundwater come from artificial fertilizers and manure from farming operations, according to the 2015 report of the Groundwater Coordinating Council. Nitrate in drinking water systems is increasing, the council found, and “current management activities to limit nitrate pollution have questionable effectiveness.”

In addition to blue baby syndrome, researchers are studying other possible health effects from nitrate in drinking water, including several cancers, thyroid problems, birth defects and diabetes. Nitrate can convert to compounds that are “some of the strongest known carcinogens,” according to the state groundwater council.

Nutrient management plans are the state’s main tool for addressing the problem. They help farmers apply nitrogen and phosphorus at the right rate to keep nutrients out of surface and groundwater.

“(But) nutrient management plans clearly don’t protect groundwater if we mean anything close to maintaining the drinking water standard,” said George Kraft, a professor of water resources at UW-Stevens Point who is the governor’s representative to the council.

Last year, the groundwater council made protecting groundwater from nitrate and other agricultural contaminants one of three top-priority recommendations for the state.

The state DNR, which is responsible for protecting groundwater, declined to provide anyone for an interview with the Wisconsin Center for Investigative Journalism about nitrate in Wisconsin’s drinking water. Former agency spokesman Bill Cosh also refused to answer questions about what strategy DNR was pursuing to reduce nitrate, directing a reporter instead to previously published reports.

But DNR drinking water chief Jill Jonas acknowledged at a 2014 scientific conference on nitrogen’s environmental impacts held in Madison that Wisconsin has “a worsening problem that we need to tackle.”

In October, 16 Wisconsin residents, including the Joneses of rural Spring Green, filed a petition with the U.S. Environmental Protection Agency seeking to force the DNR to correct deficiencies in its enforcement of the federal Clean Water Act.

Katie Kowalsky / Wisconsin Center for Investigative Journalism

The petitioners allege DNR has failed to adequately protect ground and surface waters that provide drinking water to the state. The agency has responded by saying it takes its responsibilities under the law seriously.

As bad as it is now, Wisconsin’s groundwater nitrate contamination overall is likely to increase long before it stabilizes, Kraft and other groundwater experts said, due to the lag time between when nitrogen is applied to the surface and when it reaches the water.

A team of researchers led by the EPA estimated in 2008 that agricultural nitrate may cost the nation $157 billion per year. Nitrate’s direct damage to drinking water supplies was estimated at $19 billion, with some of the greatest costs borne by Upper Midwest states including Wisconsin, Minnesota, Iowa, Illinois, Ohio, Michigan and Indiana. Much of the cost was attributed to a projected increase in colon cancer among those drinking contaminated water.

Jonas told the scientific conference last year that the costs of testing and treatment to remove nitrate pollution are growing statewide, “and it certainly is unsustainable.”

Dairy’s role scrutinized

In a handful of recent court cases, nitrate pollution has come front and center as rural residents have challenged large livestock operations. A Wisconsin judge in 2014 cited Kewaunee County’s widespread pollution of drinking water by nitrate and bacteria as evidence of “massive regulatory failure” by both federal and state agencies — a view that the DNR refutes.

Some residents there have pointed to the large dairy farms, known as concentrated animal feeding operations, as the most likely culprits for their polluted water. They have filed a separate petition asking the EPA to provide them with emergency safe drinking water and to investigate the sources of the nitrate pollution. Many also want tighter regulation of the dairies to protect the area’s vulnerable karst topography, where aquifers lie underneath shallow bedrock filled with cracks and holes.

In a case that all sides agree could set a national model, a federal judge in Washington state in May sided with environmental groups in ruling that several large Yakima dairies’ manure had polluted drinking water supplies with nitrate and posed an imminent threat to human health. The dairies were ordered to provide clean drinking water to hundreds of neighbors with contaminated wells.

Manure from dairy operations is blamed in part for nitrate that pollutes the drinking water in some parts of Wisconsin. Kate Golden / Wisconsin Center for Investigative Journalism

Giant dairy farms have mushroomed as Wisconsin’s industry has consolidated. The Wisconsin Dairy Business Association, an industry group, has fought the notion that the large farms have tainted drinking water by citing the looser regulation of small farms and the presence of human, as well as animal, waste in wells.

The group acknowledges agriculture’s role in the overall problem — and potential solutions.

“If anything, these dairies will be a big part of any improvements going forward,” said the association’s representative John Holevoet, adding that such farms “have embraced regular soil testing and detailed nutrient management planning in a way that others have not,” and pointing to research and technologies to improve the efficiency of nitrogen use.

“The reality is, manure management has never been better or more sophisticated than it currently is. It will only get better,” Holevoet said.

However, even farmers who are following best farming practices set out by federal or state agencies may pollute the groundwater, particularly in areas with geologically vulnerable aquifers such as northeastern Wisconsin’s karst areas or the Central Sands region.

Kevin Masarik, a groundwater education specialist at UW-Stevens Point’s Center for Watershed Science and Education, said some of the factors are beyond farmers’ control.

“We don’t have a lot of tools in the toolbox to address nitrate in groundwater,” he said.

Blue babies and birth defects

Nitrate in drinking water poses a “serious health risk to infants and pregnant women,” said Roy Irving, a state Department of Health Services toxicologist. Those who are most at risk are babies who drink formula made with nitrate-contaminated well water; breastfed infants appear to be fine even if their mothers drink polluted water.

Wisconsin’s public health officer, Henry Anderson, said his department typically finds one or two cases of blue baby syndrome per year through scanning hospital discharge and emergency-room databases.

But the department does not follow up to find out if the cases were water-related, he said, as the illness can also be triggered by medications or a rare congenital disorder. Anderson and other experts said they believed outreach by pediatricians and public health officials has been effective.

Dick Swanson of Algoma carries dolls painted blue to highlight “blue baby syndrome,” a condition caused when infants drink water polluted by nitrate. Swanson, a member of the advocacy group Kewaunee Cares, attended a “stink-in” with about 50 others on the steps of the Wisconsin State Capitol on Nov. 7 to protest pollution from concentrated animal feeding operations. Activists blame large-scale farming operations for contaminating drinking water in Kewaunee County and elsewhere. Abigail Becker / Wisconsin Center for Investigative Journalism

“Every visit, we ask, ‘What kind of water do you use? Do you have a well?’ ” said Dr. Beth Neary, an environmental health advocate whose longtime Madison pediatric practice included many mothers from rural areas. “But there’s got to be people who don’t go to the doctor.”

Last year, the Department of Health Services updated its health advice to warn women who may become pregnant to stay away from water with high nitrate levels, based on emerging research linking the chemical to birth defects.

In one 2013 study of 3,300 Iowa and Texas case mothers and 1,121 control mothers, those whose babies had spina bifida, cleft palate or lip, or a limb deficiency were all more likely to have drunk at least 5.4 milligrams of nitrate a day, which is under the health standard.

Some of those health effects, researchers have written, may be caused not by the nitrate itself but by contaminants, including pesticides, that often occur with it.

Dismaying statewide trend

In 2014, Masarik and a group of UW-Madison and state of Wisconsin collaborators analyzed a decade’s worth of data for more than 8,500 churches, bars and other “transient non-community water systems” that are required to test at least annually for nitrate.

They projected that given the rising or falling nitrate levels among those wells, about 687 non-community systems, or 8 percent of the total, would eventually need to invest in a new well or a treatment system.

Because nitrate can take time to make its way down to aquifers, some recent trends may be the result of land use practices from decades ago. Improvements made now may take years to bear fruit.

Kevin Masarik, a groundwater education specialist at the University of Wisconsin-Stevens Point’s Center for Watershed Science and Education, is seen here at Wisconsin Farm Technology Days near Sun Prairie in August. “I don’t think we have fully realized what the extent of nitrate (in groundwater) is throughout Wisconsin yet,” he said. Ron Seely / Wisconsin Center for Investigative Journalism

“I don’t think we have fully realized what the extent of nitrate is throughout Wisconsin yet,” Masarik said. “I think there’s areas where we’re going to continue to see wells exceeding the standard that maybe in the past have not been.”

Masarik described how the Joneses saw their well water creep up over 20 milligrams per liter of nitrate — twice the safe limit. Doug Jones wondered if a 15-acre field he was renting out, on which corn and soy was growing, could be to blame. Would taking land out of production improve his well water?

“I don’t know,” Masarik told Jones, offering to monitor the water.

Two years later, the nitrate levels had decreased. But, Masarik acknowledged, it is not a strategy that most well owners have the “luxury” to employ.

People always ask him: What about septic systems?

In some areas they are to blame. Human waste is rich with nitrogen, just like animal waste. Septic systems that are improperly constructed or placed in areas with vulnerable geology can lead to polluted wells.

Statewide, septics account for about 9 percent of the nitrate inputs to groundwater. Lawn care contributes another 1 percent. Artificial fertilizer and manure contribute the remaining 90 percent.

Masarik estimates that to match the water quality impact of a 20-acre field of corn, those 20 acres would have to have 36 normally functioning septic systems on them.

“Nobody really wants to think that it’s because of them,” Masarik said, but added, “If you want to have an intelligent debate about where it’s coming from and how you can fix it, it’s important to really understand the source.”

Nutrient management no fix

Fertilizer usage has about quadrupled since 1960 nationwide, according to U.S. Department of Agriculture figures. The state Department of Agriculture, Trade and Consumer Protection estimates that farmers applied over 200 million pounds of nitrogen in excess of UW-Extension crop recommendations in 2007.

Masarik said the nitrate problem is not mainly about farmers heedlessly polluting the landscape by over-applying nitrogen. The trouble is that no plant is perfect at soaking up nutrients.

The state agriculture department says nutrient management planning is one of the best ways to prevent excess nutrients from tainting the water. Wisconsin’s current standards are among the most stringent in the nation, agency spokeswoman Donna Gilson said, and revisions currently underway will require “substantially stronger restrictions” on spreading nutrients for certain soil types, in winter and near conduits to surface or groundwater.

The porous soil of Wisconsin’s Central Sands region allows manure and other fertilizers from farming operations to make their way into the aquifer, sometimes polluting the groundwater and drinking water with nitrate. Kate Golden / Wisconsin Center for Investigative Journalism

But state agriculture officials’ view of these plans’ effectiveness in addressing nitrate is rosier than that of groundwater experts Kraft and Masarik. Masarik, who was involved in research examining the effectiveness of such nutrient management planning, said the strategy may still result in contaminated wells unless farmers rotate their crops.

Even revisions to the nutrient management standards are unlikely to dramatically improve water quality, Masarik said. The benefits of such plans “may have been oversold in some cases — or misunderstood in terms of what’s actually realistic,” he said.

For one thing, such plans sometimes increase the use of nutrients. A survey of 259 Wisconsin farmers, most of whom grow corn and soybeans with livestock, found that 51 percent increased their nitrogen applications after implementing nutrient management planning.

Well testing is rare

Private well owners in Wisconsin are not required to test their wells, and very few have done so, let alone on the annual schedule that public officials recommend. In some areas, even annual tests may not be often enough to guarantee safe water because pollution can spike one month and disappear the next.

Petitioners Sherryl and Doug Jones feel the state Department of Natural Resources has left residents to fend for themselves when it comes to ensuring the quality of their water.

What do the Joneses want?

“We all are entitled to clean water, drinking water,” Doug Jones said. “There’s no reason why with this day and age and all the science and technology that something can’t be done to improve the situation because it just seems to be getting worse.”

Others favor a change in state law, including mandatory testing of private wells.

“Leaving it up to the individual citizen is just not good public health policy,” pediatrician Neary said.

Masarik, who spends much of his time encouraging people to test their wells, cautions that such a requirement could add a layer of bureaucracy without making the public any safer. What would well owners whose tests found nitrate be required to do?

In some situations, “you kind of have to weigh your options,” he said. “The government is not going to be able to make those decisions for them.”

Masarik believes the government’s most helpful role is educating health care providers, local health departments and rural well owners about their responsibility to test their water, especially when buying a piece of property or when a baby is on the way.

Short-term fixes costly

The cost of solving a nitrate problem for a household can run from hundreds of dollars a year for bottled water or water treatment systems to thousands of dollars to drill a new well. Treatment systems, in particular, require maintenance — and are no guarantees of safety, as another case from the Wisconsin Medical Journal illustrates.

Case 4 was a baby girl from Eau Claire County weighing 6 pounds and 10 ounces. She had been healthy for the first month of life. But she started to throw up after feedings and had loose stools. She was treated for dehydration and went home the next day.

Six days later she was readmitted and was described as “wasted and dusky,” or in other words, blue.

She had drunk formula made with well water. The family knew the water was contaminated and was filtering it with a reverse osmosis system.

A water sample taken while Case 4 was hospitalized showed nitrate at 9.9 milligrams, right near the health standard, with later samples at 12.5 and 23.5 milligrams per liter.

It turned out the family’s solution — a filter — was no solution at all.

Reporter Bridgit Bowden contributed to this report. Portions of the series were produced in collaboration with journalism classes participating in The Confluence, a project involving the Wisconsin Center for Investigative Journalism and the University of Wisconsin-Madison School of Journalism and Mass Communication. The nonprofit Wisconsin Center for Investigative Journalism ( collaborates with Wisconsin Public Radio, Wisconsin Public Television, other news media and the UW-Madison School of Journalism and Mass Communication. All works created, published, posted or disseminated by the Center do not necessarily reflect the views or opinions of UW-Madison or any of its affiliates.

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Kate GoldenMultimedia director and reporter

Kate Golden, multimedia director and reporter, specializes in environmental stories and data visualizations.