Ecolution SERIES: Diving Deep Into Minnesota Waters (Part 1)

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As our Changemakers Alliance (CALL) newsletter reported in May, we visited Lewiston in southeastern Minnesota for a town hall forum about the water quality issues there. In this deep dive story, we will offer details about statewide water quality issues — such as runoff from agriculture and cancerous toxicity dangers.


As the Lewiston forum revealed, when streams have been polluted with toxic chemicals — from high use of pesticides, metals, ammonia — and bacteria, large numbers of fish die.

Monta Hayner, a fly fishing guide, talked about the importance of clean water to the tourism economy of Minnesota, and wrote a story for our Rivers issue in August. As she wrote: “The rivers and topsoil of this region were heavily damaged by row farming on hills; a massive amount of soil was eroded and buried the town of Beaver in the early 20th century. Farmers now contour-farm these hills with grasses planted where the water runs off, but the current regulations and laws do not prevent the runoff of nitrates into the water.”

Drinking Water

City water quality can be affected by high levels of nitrates, as has happened in Lewiston, Utica, Bethany, and Aurora in southeastern Minnesota. High levels of nitrate can cause cancers, thyroid issues, and an inability to carry oxygen throughout the body, which especially is dangerous to babies.

Properties that have private wells, which often happens in rural areas — impacting more than 1 million people — are impacted by chemicals from livestock and crop fields that seep into the watershed. In the karst landscape of Winona County, where groundwater and surface water more easily intermingle, this is particularly dangerous — and expensive to treat: 19 percent of wells tested there so far have nitrate concentrate greater than the EPA safety standard of 10ppm, with 55 percent of wells in Fremont and 47 percent in Utica testing over the recommended limit. Most wells are not tested.

Organic compost can relieve some of the toxicity seepage, as can the use of cover crops that reduce nitrogen levels.

Paul Wotzka (right) is a hydrologist who lives in the area and co-founded the Minnesota Well Owners Organization to host water testing clinics and advocate for policy changes. Some farm owners in the area have seen their nitrate levels climb to 22ppm in a few years. He and other advocates are seeking Clean Water funds to help pay for solutions for private well owners, who tend to have low incomes and unsafe drinking water.

Advocates and government sources say some well owners are afraid to have their water tested and then be required to do something about it. Many renters do not know if their water has been tested by the owner.

Aleta Borrud, who has a master’s degree in public health and epidemiology, shared a talk at the forum titled “Do dying fish tell us something about the risk to us from our drinking water?” The short answer: yes. She indicated there are particularly dangers to pregnant women who are exposed to high levels of nitrates, increasing risks of birth defects, spinal cord abnormalities, and more.

An Iowa Women’s Health Study worked with the University of Minnesota and Mayo Clinic on research with 40,000 women, followed for 25 years, measuring dietary nitrate coming from those who were drinking from public water sources — not private wells or bottled water. Findings suggested elevated risks of bladder, ovarian, and thyroid cancers with higher levels of nitrates, Borrud said.

Other studies find that nitrate levels are increasing in the urine samples of people across the country, which is one reason screenings for colon cancer are now recommended at younger ages.

Cancer and 3M

As Deena Winter of Minnesota Reformer reported in December 2022, 3M had been sued in 2010 for failing to report to regulators and scientists, for decades, that its chemicals could be toxic to humans and the wider environment. In 2018, 3M agreed to pay $850 million to help mediate issues with Minnesota’s drinking water.

The Reformer reviewed some of the 27 million pages of documents and depositions from 200 witnesses over seven years that were gathered by Minnesota’s former attorney general Lori Swanson, who publicly released thousands of the 3M documents. Among the findings, wrote Winter:

  • By the early 1960s, 3M knew the chemicals didn’t degrade in the environment.
  • A 1970 study of fish had to be abandoned because, after being exposed to a chemical, the fish kept crashing into the fish tank and dying.
  • By 1976, 3M knew chemicals were in its plant workers’ blood at higher levels than normal.
  • In 1979, 3M lawyers advised the company to conceal a 3M chemical compound found in human blood.
  • When someone who knew about the findings resigned in the 1990s, he wrote in his resignation letter that researchers were told not to write down their thoughts or have email discussions because of how their “speculations” might be viewed in legal discovery.

Winter also wrote the story of Amara Strande, from Oakdale in the 3M area, who died in 2023 at age 20 after dealing with headaches, nausea, frequent nosebleeds, abdominal pain, and fatigue. A rare cancer in her liver led to the removal of a nearly 15-pound tumor; later tumors were found in her kidneys, intestine, lung.

A 2017 study, Winter wrote, found that a child who died between 2003 and 2015 in the region of perfluorochemical dumps (roughly Cottage Grove, Oakdale, Woodbury, Lake Elmo) was 171 percent more likely to have had cancer than a child who died in the surrounding area.

What Advocates Want to See

Although the urban and rural watershed issues are different, they are part of the network not only of interconnected waterways but of advocates trying to get more attention paid to the health of Minnesota’s rivers and drinking water.

Kelley Stanage, an advocate who organizes southeastern Minnesota forums, is frustrated with the years of studies about best management practices that Minnesota agencies have invested in, without improving the contamination of local groundwater. “Nitrate levels in our groundwater are increasing, not decreasing,” she told us. “This is quickly becoming a public health crisis for folks with a private well, as well as those living in small municipalities throughout the region.”

She says the Winona County Clean Water Coalition has met with Environmental Quality Board staff and will be meeting with the Minnesota Pollution Control Agency. Another “Resource in Crisis” forum is planned in Winona this fall. For details:

Carly Griffith (right), the water program director for the Minnesota Center for Environmental Advocacy (MCEA), spoke at the May Lewiston forum about why the MCEA petitioned the EPA to address the nitrate concentration of southeastern Minnesota groundwater with an emergency measure. “The position we take in the petition is that these industrial scale agricultural advantages practices have not been effectively regulated by state and local government authorities,” she says. “To give you a sense of scale, in this eight-county area, there are approximately 500,000 dairy cattle units, and another 260,000 swine units — an extremely high density of those animal units on the landscape in addition to row crop activity.

Griffith said that the Clean Water Act includes exemptions for agricultural stormwater runoff, which “we think are a big part of the problem.”

A farmer with healthy soil practices — cover cropping, rotational grazing, grazers on the land, perennials — can make a difference, but Griffith says the state needs to offer more incentives to adopt those needs to build on these incentives with targeted regulation and consistent enforcement. Counties like Olmstead — with a $3 million investment and soil health experts — have been able to encourage farmers to lower runoff dangers, but it is not widespread in the region.

Water advocates seek increased public support from all communities, as well as from science, legal, and health perspectives. Specific asks in the petition to the EPA include:

  • Require polluters to provide a free and safe alternative source of drinking water for impacted communities
  • Prohibit consolidated animal feed operations from expanding until contaminated wells reach safe levels
  • Provide public notice of potential contamination events, such as manure land applications
  • Identify public water systems, private wells, or groundwater monitoring wells near potentially contaminated areas
  • Clean up contaminated soils endangering underground sources of drinking water
  • Encourage widespread adoption of cover crops and other remediation methods

Next Steps

Since the May forum (slide from presentation above), the EPA has reached out to state officials to talk about issues raised in the MCEA petition. The Olmstead Soil and Water Conservation District passed a local resolution that seeks cooperative federal, state, and local approaches to tackle nitrate contamination.

The MCEA has defined and identified vulnerable groundwater areas in Minnesota, Griffith says, with “intent to look for remedies that can help address nutrient pollution from agriculture in all vulnerable areas.” She says southeastern Minnesota has some of the highest rates of well contamination, according to state data.

“The drinking water issue in areas like the karst is tied to groundwater contamination, but we also have a huge problem with surface water contamination by nitrates,” she says. “The Minnesota Pollution Control Agency has said that 70 percent of the nitrate in our surface waters comes from cropland sources, and that water ends up downstream. It ends up in places like Lake Pepin, which has an incredible amount of both sediment and nutrient pollution, because it’s downstream of all these agricultural areas of the Minnesota and Mississippi river basins.”

Karst educational video released August 25

Advocates working to meet environmental safety goals