Total Maximum Daily Load - Planning Process

Planning Process

Beneficial use determinations must have sufficient credible water quality data for TMDL planning.

Throughout the U.S., data are often lacking adequate spatial or temporal coverage to reliably establish the sources and magnitude of water quality degradation.

TMDL planning in large watersheds is a process that typically involves the following steps:

1. Watershed Characterization—understanding the basic physical, environmental, and human elements of the watershed.
2. Impairment Status—analyzing existing data to determine if waters fully support beneficial uses
3. Data Gaps and Monitoring Report—identification of any additional data needs and monitoring recommendations
4. Source Assessment—identification of sources of pollutants, and magnitude of sources.
5. Load Allocation—determination of natural pollutant load, and load from human activities (i.e. diffuse nonpoint sources and point discharges).
6. Set Targets—establishment of water quality targets intended to restore or maintain beneficial uses.
7. TMDL Implementation Plan—a watershed management strategy to attain established targets.