Total Maximum Daily Load Program
The Total Maximum Daily Load (TMDL) program, established under Section 303(d) of the Clean Water Act, focuses on identifying and restoring polluted Kentucky waterbodies such as rivers, lakes and streams.
What is a Total Maximum Daily Load (TMDL)?
TMDLs are a requirement of the Clean Water Act
. A TMDL is a calculation of the maximum amount of a pollutant that a waterbody can receive while still meeting water quality standards
for each designated use. All Kentucky waterbodies have assigned designated uses
(e.g. Primary Contact Recreation, a use that includes swimming and wading).
States must develop a TMDL calculation
for each pollutant causing a waterbody to be placed on the 303(d) list of impaired waters. TMDL calculations are found in TMDL reports
. A TMDL Report is a water quality restoration plan that describes how pollutant loads can be reduced to meet water quality standards. read more
Impaired Waters Restoration Process
The TMDL program coordinates with several other Clean Water Act programs such as permitting, monitoring
and the 319 Nonpoint Source Pollution Control Program
to accomplish water quality restoration goals in Kentucky. We are an integral part of the Impaired Waters Restoration Process.
Waterbodies identified as impaired by pollutants are placed on the 303(d) list in the 305(b)/303(d) Integrated Report. Once these waters are 303(d)-listed, water quality restoration planning can begin.
Kentucky is required to develop a TMDL calculation for each pollutant causing a waterbody to be placed on the 303(d) list. These calculations can be found in water quality restoration plans called TMDL reports. TMDL reports describe how pollutant loads can be reduced to meet water quality standards. TMDL implementation plans and watershed management plans can be incorporated into TMDL reports or prepared separately. Under some circumstances, other types of water quality restoration plans may be developed for waterbodies on the 303(d) list called TMDL Alternative Approaches.
After the planning phase, pollution control practices from the water quality restoration plan are implemented to reduce the amount of pollutants entering a waterbody. Discharge of pollutants can be limited by setting permit limits for point sources or implemented best management practices for non-point sources pollution.
Once the pollution control practices have had time to take effect, the impaired waterbodies will be monitored and tracked to determine if water quality is improving.
An impaired waterbody is considered fully recovered or restored when water quality standards have been met and designated uses have been achieved. This generally occurs many years after a plan was put in place.
The goal of the TMDL program and other Clean Water Act programs within the Division of Water is to manage, protect, and enhance all of Kentucky’s waterbodies so that Kentuckians will have healthy water for present and future generations to come.