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This is not the current EPA website. To navigate to the current EPA website, please go to www.epa.gov. This website is historical material reflecting the EPA website as it existed on January 19, 2021. This website is no longer updated and links to external websites and some internal pages may not work. More information »

Water Quality Criteria

The Clean Water Act requires EPA to develop criteria for surface water quality that accurately reflect the latest scientific knowledge on the impacts of pollutants on human health and the environment.  Basic Information on Water Quality Criteria.