Contaminated groundwater concerns mount in Minnesota

Contact: Risikat Adesaogun, 651-757-2056

St. Paul, Minn.--Groundwater contamination is a growing concern that should be on everyone’s radar, according to scientists at the Minnesota Pollution Control Agency (MPCA). Three out of four Minnesotans get their drinking water from groundwater sources. However, unlike our lakes, rivers and streams, groundwater is largely out of sight.

Up to 60 percent of groundwater monitoring wells sampled in central Minnesota are contaminated with nitrate well beyond the safe drinking water standard. Drinking water contaminated with nitrate can lead to illnesses such as Blue Baby Syndrome, a fatal blood disorder in infants.

Nitrate enters groundwater from sources like animal manure and agricultural fertilizers. Some of the affected cities include Becker, Clear Lake, Cold Spring, Hastings, Goodhue, Adrian and Park Rapids. City officials in those areas test their wells more frequently and have taken steps to ensure safe tap water for residents,  sometimes at great expense.  Options include distributing bottled water to residents, blending water from multiple wells prior to distribution, or spending millions to drill new wells or build reverse-osmosis water treatment plants. 

The Groundwater Protection Recommendations report highlights the current state of Minnesota’s groundwater and provides recommendations for ways to reduce and prevent groundwater contamination. Minnesota lawmakers requested the report during the 2013 legislative session.

“This report underscores the urgent need to ensure that all Minnesotans have clean water," said Governor Mark Dayton. "I look forward to discussing this report, and our state's serious water quality challenges, at the Governor's Water Summit this weekend.”

Some Minnesota cities have already experienced the cost burden of treating contaminated groundwater.  A 2014 Drinking Water report from the Minnesota Department of Health (MDH) put cost estimates for treating contaminated drinking water in Minnesota in the billions of dollars. The estimated cost for cleaning up contaminated water in Hastings was a staggering $9 million; estimated costs for Park Rapids were upwards of $11 million.

“Groundwater is one of our most precious resources. This report is another warning indicator about our water quality challenges,” said MPCA Commissioner John Linc Stine. “We know that prevention is key. It costs between 10 to 30 times more to fix contaminated groundwater than to prevent contamination in the first place.” 

Many harmful groundwater contaminants are caused by human activity. Those contaminants come from sources like urban runoff, road de-icing salt, antibiotics, pharmaceuticals, viruses and agricultural practices.

One contaminant, chloride, enters Minnesota’s groundwater from salt use during winter. While chloride is not believed to be very toxic to humans, high concentrations give drinking water a taste many people dislike. Additionally, contaminated groundwater can make its way to lakes and streams, harming fish and other aquatic life. Scientists recommend reducing the amount of road salt used during the winter months. Many local governments have already decreased their use of road salt, but more work needs to be done to reduce use on roads, parking lots, and sidewalks.

The report also includes information about naturally-occurring contaminants like arsenic, manganese and radium. Long term exposure to these can contribute to illnesses such as bladder, liver and prostate cancer. Infants are also at risk. For example, infants relying on powdered formula mixed with drinking water that contains high concentrations of manganese are at risk of developing neurological problems.

The MPCA, in collaboration with other state agencies that share groundwater responsibilities, provided 30 recommendations that will aid in protecting Minnesota’s groundwater. One recommendation includes continuing to fund programs that support clean and safe groundwater, like the MPCA’s Superfund Program. Another recommendation in the report calls for more research to better understand the impacts of contaminants on human health, especially for newer contaminants of concern like pharmaceuticals and antibiotics.

The Governor’s Water Summit in St. Paul on Saturday, Feb. 27th will focus public attention on the serious challenges facing Minnesota’s water supplies, including groundwater. The Groundwater Protection Recommendations report is available on the MPCA's contaminated groundwater webpage.