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Overview of the Impaired Waters and TMDLs Program under CWA Section 303(d)

Learn about identifying and restoring impaired waters under Section 303(d) of the Clean Water Act (CWA). Below is information about what Section 303(d) authorizes, how the listing and restoration processes works, and what TMDLs are.

Section 303(d) of CWA
Listing Impaired Waters
Total Maximum Daily Loads (TMDL)