Under the federal Clean Water Act, the Total Maximum Daily Load, or TMDL, program provides a framework for identifying and cleaning up impaired waters. The state is required to develop a TMDL for all waters included on the 303(d) list. Water Quality Monitoring Section staff contribute much of the field work required for TMDL calculation.

Brush Creek
Impairment of water quality in Missouri streams can be attributed to many pollution sources, both point and non-point. To resolve these problems, a detailed field investigation is often required to define the nature and extent of impairment. These types of field investigations are commonly referred to as wasteload allocations or special stream studies. These studies are performed in localized areas to delineate water quality problems. Data acquired from wasteload allocation and special stream studies are utilized to determine TMDLs for Missouri streams that have been designated as impaired.

After management controls have been implemented on an impaired waterbody, it is often necessary to perform additional studies to reassess water quality or biotic integrity. This allows the Water Pollution Control Program to determine the success or failure of controls that were implemented.