Wisconsin´s Impaired Waters Program

The federal Clean Water Act (CWA) requires states to adopt water quality standards to protect waters from pollution. These standards define how much of a pollutant can be in the water and still allow it to meet designated uses, such as fishing and swimming.

The standards are set on a wide range of pollutants such as: phosphorus, sediment, bacteria (E.coli), PCBs and mercury. A water body is polluted or "impaired" if it fails to meet one or more water quality standards.

Wisconsin´s Impaired Waters Program is required by Section 303(d) of the Clean Water Act to identify and restore impaired waters by:

1. Evaluating and assessing all waters of the state to determine if they meet water quality standards.
2. Creating a list of waters, or Impaired Waters List, of those waters that do not meet water quality standards.
3. Conducting a TMDL analysis to set pollutant reduction goals needed to restore waters.

WDNR performs assessment and monitoring activities on Wisconsin waterbodies, lists impaired waters and conducts TMDL analyses on impaired waters. WDNR is committed to working with watershed partners to meet water quality restoration goals. Wisconsin´s waters are valuable resources and clean water can bring quality of life benefits to everyone.