Iowa private well water often goes untested, presenting unknown health risks

Lauren Mills Shotwell, originally posted on December 26, 2016


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

Moreover, many well owners IowaWatch spoke with during an investigation this past year in counties across southwest Iowa said they largely were unconcerned about their wells, 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 found while researching and testing wells in a 10-month investigation a large percentage of wells with high nitrate and bacteria levels. Nitrate levels in 28 wells IowaWatch, a nonprofit, nonpartisan 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 (NO3) and the acceptable level for that under U.S. Environmental Protection Agency health standards is 45 milligrams per liter, although the level usually referenced for nitrogen is 10 milligrams per liter.

Eleven of the wells IowaWatch tested in May and June had nitrate levels above 45 milligrams per liter. Two more tested at 43. Fifteen wells showed unsafe bacteria levels but 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 well owners to understand the importance of testing their water regularly, even if it looks, smells and tastes fine.

“What’s out of sight is out of mind,” said Sherry Storjohann, an environmental health specialist who has been testing wells in Crawford and Carroll counties for the past 25 years.

“I have so many people with hand-dug wells that say they’ve got the best tasting water, the clearest water, the coldest water,” she said. “Yet what they realize after they test is just how unsafe that water is.”

While some contaminants — like bacteria — may not necessarily be a health concern, they are an indicator of a well susceptible to contamination from the outside. Outside contaminants can include runoff from agricultural fields, septic system leaks and animal infestations, such as when mice, snakes or other creatures crawl into an unsealed well. In some cases, natural events like flooding can also pose a risk to a well.

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

Arsenic and lead both pose a largely unknown risk at low levels. The Environmental Protection Agency puts maximum contaminant level goals, at which there is no known or expected health risk, at zero for both arsenic and lead.

Iowans who wish to test their well 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, taking a sample and sending it in. Or, in 98 of Iowa’s 99 counties, they can go through their county sanitarian and use a program called the Iowa Grants to Counties Program.




When Jenny and Craig Melvin moved into their home outside Farragut, they tested their well through their local county sanitarian. Results came back with high nitrogen levels — 74 milligrams per liter — and total coliform bacteria present. They shocked the well, which cleared up the bacteria, but the nitrates still were there. With one infant in the house both 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.”

IowaWatch testing also showed the Melvins had slightly elevated levels of arsenic and lead in their water — 0.002 milligrams per liter for both contaminants. Although the goal would be to have these contaminant levels at zero, the action level for lead in regulated, public water supplies is 0.015 milligrams per liter, and for arsenic the maximum contaminant level is 0.010 milligrams per liter.

Water from their well comes straight into the house without filtration. Craig Melvin said he’s not the type to get too concerned about the water, although he pointed to the location of the well as cause for some concern. It’s about 800 feet from the house in a low point in the landscape, surrounded by fields, near a runoff ditch.

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




Iowa’s Grants to Counties Program, established in 1987 when the state Legislature passed the Iowa Groundwater Protection Act, provides funds for local county health departments to be used for an array of well-related services.

The program has several players, including the Bureau of Environmental Health Services in the Iowa Department of Public Health, which takes care of the financial administration, and the Iowa Department of Natural Resources, which takes care of some of the technical aspects like well contractor certification and maintaining a database of wells and water test results.

All but one of Iowa’s 99 counties — Marshall County — participate. Carmily Stone, bureau chief of the Bureau of Environmental Health Services in the Iowa Department of Public Health, said the program was among her favorites of the services she oversees.

“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?,” she said. “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.”

Counties also can use a grant to cover well-related training expenses up to $1,000, up to $500 for the cost of supplies and up to $1,000 for advertising and promotions to let people know about the availability of the well services. The grant does not cover expenses for water treatment systems.

Some counties may choose to put all of the money into testing and services like plugging or reconstruction, while some divvy up the funds for supplies, training and promotional expenses as well.

As science has yielded a better understanding of the potential for contaminants in wells and the impact those contaminants can have on health, the challenge is keeping people updated and informed on the importance of testing.

Storjohann said both her parents and her grandparents followed the common practice of never testing their wells. “They were of the adage: ‘We’ve been drinking it this long, you know. It’s never harmed us,” she said.

As kids, Storjohann and she and others used to drink from the hydrant of the shallow well on her grandparent’s farm.

“I can’t imagine what we probably drank,” she said.

Richard and Ruth Miller said they’d heard about other people with contaminated wells and thought they should get their well checked, especially since they have grandkids coming over every week. The Millers live near Silver City in Mills County. IowaWatch tests this past summer showed bacterial unsafe levels of coliform bacteria at their home but barely a trace of nitrogen and no e.coli.

Although they test, they said they don’t worry much about their water.

“Nothing beats good old country water,” Ruth Miller said.

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