State agencies pledge new steps to reduce nitrate in southeast Minnesota

Cows graze in a heavily used pasture
Cows graze in a heavily used pasture in rural Winona County. The Minnesota Pollution Control Agency says cropland agriculture is the major source of nitrate contamination in southeastern Minnesota.
Kirsti Marohn | MPR News

State agencies told the U.S. Environmental Protection Agency on Friday they will do more to address nitrate contamination in southeast Minnesota’s karst region.

Earlier this year, environmental groups petitioned the EPA, saying nitrate in eight southeast Minnesota counties’ drinking water poses an imminent health risk. 

Last month, EPA regional administrator Debra Shore said state agencies need to develop a comprehensive plan to tackle the problem. She gave them 30 days to respond.

In a Dec. 1 letter, commissioners of the departments of health, agriculture and the Pollution Control Agency agreed nitrate in drinking water is an “acute health risk for some Minnesotans,” particularly more than 1 million who get their drinking water from private wells.

They said the state already is working to reduce nitrate pollution, but promised to do more — but said they may need more federal or state money to do so.

That includes launching a public outreach and education campaign, and identifying and notifying affected residents with private wells with nitrate levels above the health risk limit. For those vulnerable to health impacts from nitrate — pregnant people and infants — the agencies said they will provide vouchers for bottled water through clinics and faith communities.

The agencies also pledged to investigate long-term strategies to reduce nitrate in the state’s waters. They cited efforts already underway — including a plan to manage nitrogen fertilizer by working with local farmers to adopt better practices, and a rule prohibiting farmers in sensitive areas from applying fertilizer in the fall, when it’s more likely to run off or leach into groundwater.

Environmental groups have criticized Minnesota’s largely voluntary approach to addressing nitrate, saying it has failed to yield results despite decades of effort and millions of dollars spent.

Most of the nitrate contamination in southeast Minnesota comes from commercial fertilizer or manure applied to cropland. The region’s karst geology allows water and contaminants to travel quickly from the surface to the groundwater below.

Drinking water with high nitrate levels poses a health risk to humans, especially infants that can develop a sometimes-fatal condition called blue baby syndrome.