The Total Maximum Daily Loads Program

Purpose of the Program

Where water's of the nation are not meeting appropriate water quality standards after implementation of technology-based effluent limits or other pollution control programs, the Federal Clean Water Act requires that Total Maximum Daily Loads (TMDL) be established for the pollutants of concern.

The quality of our nation's waters is protected through States' development of pollution control strategies. These strategies are constructed in cooperation with a broad array of stakeholders and are designed to achieve the Water Quality Standards (WQS) established for the nation's rivers, lakes, estuaries and coastal waters.

View a diagram of the water quality management process and a companion document to that diagram.

To view a more in depth discussion on TMDLS, please read Dr. Wesley Jarrell's paper "Getting Started with TMDLs", a YSI Inc. publication.

In addition, please see the America's Clean Water Foundation Report by Walt Poole "The TMDL Opportunity: Up-Front Involvement vs. End-Of-Pipe Headache", published by Business & Legal Reports, Inc.

The Total Maximum Daily Loads (TMDLs) program is one of those,
which are required by the 1972 Clean Water Act in Section 303(d).

Under this program States must:

• Identify waters that do not meet WQS after application of existing control requirements, and prioritize those listed waters.

• For each waterbody, a TMDL must be determined for each pollutant causing a WQS violation.

For an example of a state program see: Oklahoma: Water Quality Management 101.

TMDLs provide a framework, which strengthens efforts to improve water quality. TMDLs identify pollutant reduction goals needed to meet water quality standards.

Therefore, a TMDL is comprised of the maximum load of a pollutant that a waterbody can receive and continue to be able to meet the WQS.

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