Total Maximum Daily Load Program: Communities Working Together to Improve Water Quality
A Total Maximum Daily Load is a scientifically-derived target for water quality that tells us the greatest amount of a particular substance that can be added to a water body without compromising its health. The TMDL gives us a measurable goal to protect and improve the quality of our streams, lakes, and bays.
Substances considered in a TMDL are not necessarily harmful in and of themselves. For example, phosphorus is an essential nutrient, but too much phosphorus can lead to an overgrowth of algae. Another example is bacteria, which occur naturally in both human and animal waste. But too much bacteria can make it more hazardous to swim in a creek, lake, or bay—activities called “contact recreation” in the state’s standards for water quality.
Projects of the TMDL Program
Find impaired or threatened water bodies where the TMDL program is protecting people and aquatic species by reducing pollution.
TMDLs and their Implementation
Learn what a TMDL is and how TCEQ and stakeholders make a difference in the quality of our water bodies.
Developing TMDL Projects
Read guidelines for organizations that develop or implement TMDLs in Texas.
All Impaired Waters, 2022
Review a list of water bodies with Category 4- and 5 impairments in the EPA-approved Texas Integrated Report of Surface Water Quality.
Segments with TMDLs
TCEQ must consider TMDLs in permits it issues under the Texas Pollutant Discharge Elimination System (TPDES). Permits identify the classified segment to which wastewater is discharged.
Summary of Completed TMDLs and I-Plans
After a TMDL is complete, I-Plan development or approval may be incomplete. The list includes dates of adoption or approval by the commission and EPA.
News
Read the latest about TMDLs, I-Plans, and water quality.
Calendar
Learn about upcoming stakeholder meetings.
Participating in TMDL Projects
Get involved in your watershed.
Get TMDL News Updates
Receive e-mail or text updates from the Total Maximum Daily Load program
Preserving and Improving Water Quality
Read an overview of how TCEQ defines, measures, evaluates, and manages the quality of surface waters in Texas.
Watershed Action Planning
Review strategies and plans for protecting and improving the quality of the state's streams, lakes, and estuaries.
Hydrography Data and Map-Based Data Viewers
Access GIS-based data viewers and GIS data for classified segments and other surface water information.
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