Developing TMDL Projects
Overview
The goal of a TMDL is to restore the full use of a water body that has limited quality in relation to one or more of its uses. The TMDL defines an environmental target by determining the extent to which a certain pollutant must be reduced in order to attain and maintain the affected use. Based on this environmental target, the state develops an implementation plan to mitigate sources of pollution within the watershed and restore full use of the water body.
The TCEQ and the Texas State Soil and Water Conservation Board (TSSWCB) work closely on the preparation and approval of TMDLs when one or more of the sources of pollution are from agriculture or silviculture. A Memorandum of Agreement between the TCEQ and the TSSWCB provides the framework for collaboration between the two agencies to develop and implement TMDLs. For additional information or questions about TMDLs managed by the TSSWCB, see the TSSWCB’s TMDL Program web page. 
For an overview of the TCEQ’s approach to defining and managing the quality of surface waters in Texas, see Preserving and Improving Water Quality. Read Texas Surface Water Quality: What Is It, and How Is It Measured? (PDF) for a brief overview of water quality standards and the means by which surface water quality is evaluated.
Return to topHydrography
- Data and Maps
Texas stream segments, 303(d)-listed waters, and river basins, including GIS data. - Atlas of Texas Surface Waters
The Atlas depicts the state’s surface waters according to the TCEQ’s system for classifying river basins and water body segments, including lakes, bays, ponds, reservoirs, streams, rivers, estuaries and wetlands. Order printed copies by phone, fax, or mail. Be sure to reference publication number GI-316.
Guidance for Project Lead Organizations
A lead organization accepts primary responsibility for guiding a TMDL project. Often, the TCEQ is the lead organization. However, the TSSWCB, other state agencies, consultants, universities, river authorities, communities, or private consortiums may lead the development of TMDLs. Ultimately, the TCEQ is responsible for ensuring that all TMDLs developed for Texas water bodies conform with state and federal law; therefore, the TCEQ participates in all TMDL projects, regardless of who leads them.
The June 1999 guidance for the state's TMDL program is no longer applicable to the TCEQ's TMDL projects. Guides and procedures provided on this Web page supercede all similar topics addressed in the June 1999 publication. For guidance on topics not addressed on this Web page, please contact the TMDL Program at tmdl@tceq.texas.gov or 512-239-6682.
Collecting Data
Guides and procedures for collecting surface water quality data under the state’s quality-assured program.
Managing Data
Guidance, forms, and contact information for people who monitor and manage surface water quality under the state’s assessment program.
Quality Assurance
Quality assurance project plans (QAPPs) and quality assurance plans (QAPs) are required for all TMDL projects. You can obtain shell documents from your TCEQ project manager on the TMDL Team.
The EPA provides tools and guidance for quality management on their website. All approved TCEQ QAPPs are consistent with EPA guidance.
See the TSSWCB’s Environmental Data Quality Management Web page for their quality assurance documents.
Federal Regulations and EPA Guidance
The U.S. Environmental Protection Agency (EPA) administers the federal TMDL program.
Text of Section 303(d) of the Clean Water Act
For More Information
E-mail us at tmdl@tceq.texas.gov or call us at 512-239-6682.
