Test your water for nitrate
Nitrate in groundwater is due largely to agricultural activity and is linked to negative health effects including cancer, birth defects, even infant death. Farm run-off that gets into our groundwater, lakes, and streams contains dangerous pathogens, bacteria, and chemicals. Nearly 100,000 homes in Wisconsin have wells contaminated with nitrate.
When and how to test
You should test your private well at least once a year for nitrate. More frequent testing may be useful if there are any known sources of nitrate nearby or if high nitrate concentrations are found in neighboring wells. The only way to know if your drinking water contains nitrate is to have a water sample from your private well tested by a certified laboratory.
There are many public and private labs that test well water. The Department of Natural Resources (DNR) maintains a list online here or you can contact your local health department. A test kit (including sampling instructions) may be obtained from any laboratory certified to test water for bacteriological and nitrate contamination. Make sure you carefully follow all instructions for sampling and handling.
If your water tests above the limits for nitrates, you should stop drinking your well water.
Read this informational sheet from UW Extension on ways to improve water quality in your home. Unfortunately, fixes like well replacement and whole-house filtration systems are often very expensive and are not foolproof.
The most reliable way to fix water quality issues is to prevent drinking water pollution in the first place.