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Total Maximum Daily Load (TMDL) Development

TMDL Background Information

Section 303(d) of the Clean Water Act (CWA) requires states to submit a list (303(d) List) of surface waters that do not meet applicable water quality standards (impaired waters) for which implementation of technology-based effluent limitations alone do not ensure attainment of applicable water quality standards. The list of impaired waters includes priority rankings for establishment of Total Maximum Daily Loads (TMDLs) for these waters.