Apr 20, 2020

Private Wisconsin Well Water Study Finds Contamination

A study of private well water quality in three southwestern Wisconsin counties has found contamination

drinking water

An ongoing two-year study of private well water quality in three southwestern Wisconsin counties has found contamination from human and livestock waste and pathogens.

New and better wells will not be enough to produce safer drinking water, according to one of the study’s lead researchers.

“You just can’t construct yourself out of contamination,” said Mark Borchardt, a microbiologist for the U.S. Agricultural Research Service.

The study also produced findings that echoed a similar study in Kewaunee County from 2015 to 2017, according to the Wisconsin State Journal. 

27 of 34 wells previously found to be contaminated turned up evidence of human or livestock fecal matter or both. These results are from samples taken in November as part of the Southwest Wisconsin Groundwater and Geology study of Grant, Iowa and Lafayette counties.

Samples taken a year ago showed 32 of 35 contaminated wells and samples in August showed 25 of 34 contaminated wells. The samples were drawn from a subset of wells that had already tested positive for contamination, out of a total of more than 800 wells tested in 2018 and 2019, according to the Wisconsin State Journal.

Contaminants in the samples include: Cryptosporidium, rotaviruses and salmonella and other bacteria.

Samples taken from 301 wells in November 2018 found 42% were contaminated with coliform bacteria found in feces or levels of nitrate. 539 wells in April 2019 showed 27% of them were contaminated.

SWIGG researchers plan to issue one more set of test results for samples taken in early March from another set of contaminated wells. A final report on the study is expected by the end of 2020.

In December, the state’s then-agriculture secretary canceled a vote on farm-siting rules, which would have extended setbacks for manure and livestock structures and required odor-management plans

In 2018, former Gov. Scott Walker approved stricter standards for disposal of manure in 15 eastern Wisconsin counties that have vulnerable groundwater.

The Department of Natural Resources kicked off a 30-month process to create new restrictions on manure and fertilizer use in certain parts of the state in December. The restrictions would be modeled on those approved for the 15 counties in 2018, reported the Wisconsin State Journal.

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