Identifying and Restoring Wisconsin's Impaired Waters

Section 303(d) of the federal Clean Water Act requires states to develop a list of impaired waters, commonly referred to as the "303(d) list." A water body is considered impaired if

a) the current water quality does not meet the numeric or narrative criteria in a water quality standard or
b) the designated use that is described in Wisconsin Administrative Code is not being achieved.

1998 Impaired Waters List

In 1998, the WDNR substantially updated its Impaired Waters List.

Approved 1998 List (PDF 4.5 MB)

Last Revised: Monday February 18 2008