Public Safety

Private wells may pose health risks

Good-tasting water sometimes belies high nitrate levels

Craig Melvin talked about his well, located in a field a short distance from his house near Farragut, Iowa, on Aug. 19,
Craig Melvin talked about his well, located in a field a short distance from his house near Farragut, Iowa, on Aug. 19, 2016, as a storm rolled in. When Melvin and his family first moved into the house around Easter, they had to treat the water with chlorine to address some bacteria issues. The well, built in 1980, also had high levels of nitrogen and trace levels of arsenic and lead. (Lauren Mills Shotwell/IowaWatch)

Roughly 288,000 Iowans rely on private water supplies but may not know just what they’re drinking because their wells’ water quality is unregulated.

Moreover, many well owners IowaWatch spoke with during an investigation this past year in southwest Iowa said they largely were unconcerned, even though tests revealed high levels of nitrates and bacteria in some of their wells.

That could put their health and the health of their families at risk.

IowaWatch spent the past year researching wells and testing samples looking at four common contaminants: nitrogen, bacteria, arsenic and lead. Similar to a number of scientific studies, the IowaWatch review found a large percentage of wells with high nitrate and bacteria levels.

Nitrate levels in 28 wells that IowaWatch, a nonprofit news organization, tested in May and June ranged from the acceptable level of less than 1 milligrams per liter to, at one rural home, 168 milligrams per liter.

The State Hygienic Lab measures nitrogen levels using nitrate. The acceptable level for that under U.S. Environmental Protection Agency health standards is 45 milligrams per liter.

Eleven of the wells IowaWatch tested had nitrate levels above 45 milligrams per liter. Two more tested at 43. Fifteen wells showed unsafe bacteria levels. A handful also had trace amounts of arsenic and lead.

Many county sanitarians who test well water for common contaminants like bacteria and nitrogen said they struggle to get owners to understand the importance of testing their water regularly.


“I have so many people with hand-dug wells that say they’ve got the best-tasting water, the clearest water, the coldest water,” said Sherry Storjohann, an environmental health specialist who’s been testing wells in Crawford and Carroll counties for 25 years. “Yet, what they realize after they test is just how unsafe that water is.”

While some contaminants may not be a health concern by themselves, they are an indicator of susceptibility to contamination from the outside — like runoff from agricultural fields, septic system leaks and animal infestations.

High levels of nitrogen pose a health risk to infants in the form of blue-baby syndrome, in which an infant becomes lethargic or worse. Some studies have shown increased risks for some types of cancers, reproductive issues, diabetes, and thyroid conditions.

The risk of low levels of arsenic and lead are largely unknown, but the EPA puts maximum contaminant level goals for both at zero.

Infants and children exposed to elevated levels of lead could experience delays in physical or mental development and adults could face higher risks of kidney problems and high blood pressure. Elevated levels of arsenic increase risks of skin damage or problems with circulatory systems, and may increase risks of cancer.

Iowans who wish to test their wells may so through a number of different channels, including requesting a kit from a laboratory like the State Hygienic Lab at the University of Iowa. Or, in 98 of Iowa’s 99 counties, they can go through their county sanitarian.


When Jenny and Craig Melvin moved to their home near Farragut, they tested their well through a sanitarian. They found a high nitrogen level of 74 milligrams per liter, with total coliform bacteria present.

They shocked the well, which cleared up the bacteria, but the nitrates remained. With one infant in the house, Jenny Melvin and the newborn used bottled water.


“He was a preemie, so I just wanted to be extra careful,” Jenny Melvin said. “And whatever I take in, he takes in.”

Although the two previously lived in town, with town water, they grew up in the country with well water. They said they’ve enjoyed not having a monthly bill and being able to do things like fill up an aboveground pool for their kids without worrying about the cost.

The water from their well comes straight into the house without filtration. Craig Melvin pointed to the location of the well as cause for some concern. It’s about 800 feet from the house in a low point, surrounded by fields, near a ditch.

“It doesn’t smell bad or taste bad, so I’m not too worried about it, which isn’t necessarily the best thing,” he said. “We should probably be more concerned about what’s in it.”


Iowa’s Grants to Counties Program, established in 1987 when the Legislature passed the Iowa Groundwater Protection Act, provides funds for county health departments to be used for well-related services. All Iowa counties but Marshall participate.

“In public health, we prevent a lot of things and so we can’t necessarily see the impact because prevention means it never happens, right?” said Carmily Stone, chief of the Bureau of Environmental Health Services in the Iowa Department of Public Health. “But for this one, you can see the water tests being done. You can see the results that come back. You can see the wells that are plugged. You can see all of that good work happening.”

The amount of money available through a grant, which comes from pesticide and fertilizer taxes, varies each year and is split evenly among counties. The funding can be used to cover private well water tests and administrative costs for, at minimum, total coliform bacteria and total nitrate tests, with an option added in 2015 that allows counties to perform arsenic testing.

Services such as well plugging for up to $575, cistern plugging up to $375 and well reconstruction up to $1,330 also are covered under the grant.


Storjohann, the specialist with Crawford and Carroll counties, said quite a few people still are unaware of the available services despite her efforts to get the word to well owners — including visiting fairs and advertising in the newspaper.

“I’ve gotten to the point now in the last number of years where I actually send out a personal letter to homeowners trying to explain our services, hoping to generate that interest and make them understand the good service this is and what we can provide and that this is all for their benefit,” she said.

Mills County Sanitarian Mike Sukup said he tests about 150 to 200 wells a year. A portion of those are for people who get their wells tested regularly, but he said sometimes people are spurred to act when a family member gets sick or when they have kids.

Connie Schroder, who lives in Pottawattamie County near Avoca, has had the water tested periodically in her well, built in 1920 and only about 40 feet deep, since the 1990s.

She watched the nitrate results slowly tick upward — from a safe 33 milligrams per liter, to 71 milligrams in 1995 and 63 milligrams in 1997. In 1998, Schroder installed a reverse osmosis system on the kitchen tap and has used one ever since. IowaWatch tests at Schroder’s well this past summer indicated no coliform bacteria or e.coli.

“I was having babies and wondering if we could use that water for formula. That’s what caused me to test it,” she said.


Risks can depend on the region where the well is located.

Northeast Iowa, for example, has areas of karst bedrock, which State Geologist Bob Libra called “an extra kicker.”

In karst areas, the bedrock has cracks, fissures and sinkholes that provide direct connections between the surface and underground water.


Shallow wells in these areas have a higher risk for contaminants because water doesn’t filter through layers of soil.

Other areas of Iowa, including in the Des Moines Lobe, which reaches from north-central Iowa into the center of the state, are known to have naturally occurring high arsenic. Recent research and sampling have shown arsenic hot spots throughout the state, which can be hard to predict.

Different areas of the state also have inherently different water quality in the available aquifers, with generally good quality water in the northeast, hit-and-miss water quality in the northwest and poorer water quality in southern Iowa, Libra said. However, within each of those areas, depending on the lay of the land, spots of relatively good- or poor-quality water can exist.


Several well owners IowaWatch spoke with talked about switching to rural water utilities, which pipe water to areas previously not served by municipal water and are required to test their water frequently.

But for many, not having to pay a water bill is a strong incentive to stick with well water.

Even for those wanting to switch, that choice may not be available.

Ben Schaben and his wife, Jena, moved into their house in Defiance along with their three kids a little more than a year ago and found the well has both high nitrate levels and bacteria.

He said they had plans to put in a reverse osmosis system and a UV light, although a new well might be in the cards in the future.

“Rural or town water doesn’t quite come close enough,” he said. “We wish it was an option.”

This story was produced by the Iowa Center for Public Affairs, a nonprofit, online news website that collaborates with Iowa news organizations and which received a Fund for Investigative Journalism grant for this report.

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