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This information can help you learn more about contaminants in drinking water, make decisions about water testing, assess your personal health situation and understand options for water supply or treatment if needed.

Bacteria and Nitrate

Potential drinking water contaminants

    • May be found in groundwater, wells or drinking water
    • Health effects occur over time or affect individuals differently
    • Federal or state standards are set or a state health advisory level has been determined.

Some common contaminants are:

Contaminants that can occur in Wisconsin:

A - C
D - F
G - I
J - M
N - P
Q - T
U - Z

Look up contaminants in drinking water supplies

More information