Private Well Concerns

While most private wells in Wisconsin provide safe drinking water, some may be contaminated with bacteria and other pollutants.

Local health departments can learn more about private wells and other drinking water issues on our water resources page.

Flooded well? Be sure to follow these steps!

Test your well right away if you notice a change in color, look, taste, or smell.

Identify your water's symptoms to determine specific tests.

Bacteria: Test at least once a year

Contamination with bacteria can occur when work is done on the well; if the well was not built properly; or if nearby animal or septic system waste enters the groundwater.

Learn more about bacteria and manure in drinking water on our Bacteria and Manure in Private Wells page.

Nitrate: Test annually

Nitrate is one of the most common groundwater contaminants in Wisconsin and can enter groundwater from fertilizers and animal and human waste.

You can learn more about nitrate in drinking water on our Nitrate in Private Wells page.

Pesticides: Test if you have high nitrate levels

Several pesticides have been found in groundwater in Wisconsin. Normal field applications, spills, misuse, or improper storage and disposal can all lead to pesticide contamination in groundwater.

You can learn more about pesticides in drinking water on our Pesticides in Private Wells page.

VOCs: Test if you live near an old landfill or gas station

Volatile organic compounds (VOCs) are a group of chemicals that are used as solvents in many industrial and household products. Gasoline and fuel oil are mixtures of many VOCs. VOCs can enter wells from leaking underground storage tanks, landfills, and other sources, including rainwater and melting snow.

You can learn more about VOCs in drinking water on our VOCs in Private Wells page.

Other chemical concerns?

The chemical list has information on chemicals in water, along with how we come in contact to chemicals in the air or soil.


Questions? Can't find what you're looking for? Contact us!

Last Revised: March 4, 2019