Study: Private Wells Contaminated with Nitrate

By Benjamin Cox on July 5, 2021 at 8:49am

A new study has found that thousands of private drinking-water wells in the state may not be safe. A report by the Prairie Rivers Network issued on Wednesday says that many of wells may be contaminated with dangerous levels of nitrate. Clean-water advocates say more data is needed to help determine what steps need to be taken to reduce the contamination.

Nitrates have links to specific birth defects and has links to particular cancers, thyroid disease, and various other problems for adults with prolonged exposure.

The report says Illinois’ nutrient pollution is responsible for 20% of the nitrate that has resulted in a dead zone in the Gulf of Mexico. The federal limit for nitrate levels in drinking water is 10 milligrams per liter, and many well logs in rural Central Illinois show levels well above that, according to data collected by various agencies including the Illinois Department of Agriculture. The highest nitrate concentrations are shown to appear along the Mississippi and Illinois Rivers.

Locations in Morgan & Cass County sampled by the Illinois Department of Public Health show they are at the threshold of 10 milligram threshold. Northern portions of Cass show that the 10 mg level had been exceeded. Nitrate levels are higher the further north in the state.

Prairie Rivers Network recommends farmers modify edge-of-field practices and plant cover crops to reduce nitrate runoff. The network also recommends further testing and education to private well owners by the state to further reduce the problem.