Greater Trinity Region

The goal of this project is to reduce bacteria levels and protect recreational safety in waterways of the Dallas-Fort Worth Metroplex. The stakeholders and TCEQ developed total maximum daily loads (TMDLs) for several water bodies and a regional implementation plan (I-Plan), which together are the road map to improving water quality. TCEQ has adopted the TMDLs and approved the I-Plan.

Trinity River Segment 0841 at Collins Street

Watershed Counties: Dallas, Tarrant
Parameter: Bacteria
River Basin: Trinity
Segments: 0805, 0806E, 0822A, 0822B, 0841, 0841B, 0841C, 0841E, 0841F, 0841G, 0841H, 0841J, 0841K, 0841L, 0841M, 0841N, 0841R, 0841T, 0841U, 0841V

Background and Goal

Bacteria concentrations are occasionally elevated in portions of the Trinity River that flow through Dallas and Tarrant counties. High bacteria concentrations might pose a risk to people who swim or wade in natural waters. Swimming and wading are called “contact recreation” in the state’s standards for water quality; the term refers to all recreation in which people are likely to swallow natural waters.

The goal of this project is to reduce bacteria concentrations and protect recreational safety by implementing total maximum daily loads. A TMDL is like a budget for pollutants—it estimates the amount of a pollutant that a water body can receive from categories of sources and still support its designated uses.

Triangle right blue transparent TMDL Projects

Triangle right blue transparent TMDL News

Watershed Description

The watersheds for the Greater Trinity River I-Plan encompass an area of 406 square miles. The human population is 1.33 million as of 2013, with a population density of approximately 3,232 people per square mile.

Get Involved

In all its projects, TCEQ gathers opinions and information from people who represent government, permitted facilities, agriculture, business, environmental, and community and private interests in the watershed. Stakeholders are a key part of developing solutions for the Greater Trinity Region.

The North Central Texas Council of Governments (NCTCOG) is working with stakeholders to implement bacteria TMDLs throughout their region. Check back here for future meetings or NCTCOG's Upper Trinity River Basin Coordinating Committee meeting page for details.

Status and Activities

NCTCOG and entities in the watershed continued to address bacteria levels in the impaired waterways covered by the I-Plan. Highlights from 2024 include:

Drafted and distributed the annual TMDL Questionnaire to stakeholders regarding I-Plan efforts.
Hosted and facilitated the Avian Management & Water Quality Webinar, which had 22 attendees.
- Watch the Avian Management & Water Quality Webinar recording and view the presentation slides located under the Workshops and Webinars header.
Hosted and facilitated a Supplemental Environmental Projects Webinar, which had 24 attendees
- Watch the Supplemental Environmental Projects Webinar recording and view the presentation slides located under the Workshops and Webinars header
Completed multiple projects, including the
- SSO Stakeholder Slides
- TMDL Wastewater Educational Flyers Designated Towards Users
- TMDL Wastewater Educational Flyers for Carwashes, Daycares, Restaurants, and Senior Living Centers
Completed the Greater Trinity River Region TMDL Annual Program Summary and quarterly newsletters which include information on both current projects and activities completed during the year.
- The quarterly newsletters are available, under the Quarterly Newsletters header.
Coordinated two Upper Trinity River Basin Coordinating Committee meetings to provide a forum for watershed coordinators to communicate regarding current activities and ongoing efforts in the NCTCOG region.
Facilitated meetings with the TMDL Stormwater , Wastewater , and Monitoring Technical Subcommittees to plan and coordinate projects focused on reducing bacteria loading.
Facilitated the TMDL Coordination Committee meeting to give program updates, discuss upcoming projects, and to share information about an upcoming TMDL addition for North Fork Cottonwood Creek.

More details about the stakeholders' activities are available on the NCTCOG TMDL Project website and in the 2023 Greater Trinity River Region TMDL Annual Program Summary .

Technical Support Documents

Technical Support Documents for Greater Trinity Region Segments

Approved I-Plan

On Dec. 11, 2013, TCEQ approved the I-Plan developed by the stakeholders.

The stakeholders last revised their I-Plan in June 2020. It includes water bodies added by resolution.

Revised Implementation Plan, 2020

By resolution in June 2015, the stakeholder Coordination Committee added four tributary segments (0841F, 0841K, 0841N, and 0841V) of Mountain Creek Lake to this project.

Resolution Supporting the Addition of the Mountain Creek Lake Tributary Segments to the Implementation Plan

By resolution in June 2018, the stakeholder Coordination Committee added Sycamore Creek, Segment 0806E, to this project.

Resolution Supporting the Addition of the Sycamore Creek to the Implementation Plan

Adopted TMDLs

On the date of their approval by the Environmental Protection Agency (EPA), all these TMDLs become part of the state’s Water Quality Management Plan.

Addenda are created to add load allocations for assessment units that are impaired by the same pollutant or condition, within the same watershed as in the original TMDL report. Addenda are added via the State’s Water Quality Management Plan.

Updates are made to account for changing conditions in the watershed, such as new or revised wasteload allocations, permits that have been canceled or have expired, or changed facility names. Updates use the same units of measure as the original TMDL.

TMDLs	Addenda	Updates
Cottonwood Branch and Grapevine Creek On September 21, 2011, TCEQ adopted the TMDLs for Cottonwood Branch and Grapevine Creek. EPA approved them on May 30, 2012. Two TMDLs for Indicator Bacteria in Cottonwood Branch and Grapevine Creek Segments 0822A and 0822B; Assessment Units 0822A_02 and 0822B_01 Response to Public Comment on the TMDLs for Cottonwood Branch and Grapevine Creek		October 2019, Appendix III, pages 33-49 WQMP updates may be viewed in person at the TCEQ Library, Building A, 12100 Park 35 Circle, Austin, Texas. Electronic versions of updates published from 2014 through the present are available on the Texas State Library and Archives Commission website .
Lower West Fork Trinity River On September 24, 2013, TCEQ adopted these TMDLs. EPA approved them on November 7, 2013. Thirteen Total Maximum Daily Loads for Bacteria in Lower West Fork Trinity River and Tributaries Segments 0841, 0841B, 0841C, 0841E, 0841G, 0841H, 0841J, 0841L, 0841M, 0841R, 0841T, and 0841U; Assessment Units 0841_01, 0841_02, 0841B_01, 0841C_01, 0841E_01, 0841G_01, 0841H_01, 0841J_01, 0841L_01, 0841M_01, 0841R_01, 0841T_01, and 0841U_01 Response to Public Comment on the TMDLs for the Lower West Fork Trinity River and Tributaries	Addendum One: One TMDL for Indicator Bacteria in Dry Branch Creek Segment 0841I, Assessment Unit 084I_01 October 2023 WQMP Update, Approved by EPA Jan. 22, 2024
Mountain Creek Lake Upstream Watersheds On November 2, 2016, TCEQ adopted these TMDLs. EPA approved them on December 7, 2016. Four Total Maximum Daily Loads for Indicator Bacteria in the Cottonwood Creek, Fish Creek, Kirby Creek, and Crockett Branch Watersheds Upstream of Mountain Creek Lake Segments 0841F, 0841K, 0841N, and 0841V; Assessment Units 0841F_01, 0841K_01, 0841N_01, and 0841V_01 No public comments were received.	Addendum One: One TMDL for Bacteria in North Fork Fish Creek Segment 0841Q, Assessment Unit 0841Q_01 October 2019 WQMP Update, Approved by EPA March 11, 2020 Addendum Two: One TMDL for Indicator Bacteria in North Fork Cottonwood Creek Segment 0841P, Assessment Unit 0841P_01 April 2022 WQMP Update, Approved by EPA August 11, 2022
Sycamore Creek On January 16, 2019, TCEQ adopted this TMDL. EPA approved it on March 27, 2019. One Total Maximum Daily Load for Bacteria in Sycamore Creek Segment 0806E; Assessment Unit 0806E_01 Response to Public Comment on the TMDL for Sycamore Creek
Upper Trinity River On May 11, 2011, TCEQ adopted these TMDLs for the Upper Trinity River. EPA approved them on August 3, 2011. Two Total Maximum Daily Loads for Indicator Bacteria in the Upper Trinity River Segment 0805; Assessment Units 0805_03 and 0805_04 Response to Public Comment on the TMDLs for the Upper Trinity River

Dallas County Utility & Reclamation District
Dallas Downriver Club
Dallas Regional Chamber
Dalworth Soil and Water Conservation District
DFW International Airport
Fort Worth Chamber of Commerce
Greater Fort Worth Sierra Club
North Texas Tollway Authority
Park Cities Municipal Utility District (MUD)
Southwest Paddler
Tarrant County
Tarrant Regional Water District
Texas Department of Transportation (TxDOT)
Trinity River Authority (TRA)
Trinity River Environmental Education Society (TREES)

Contact the TMDL Program

Please email tmdl@tceq.texas.gov, and mention the Greater Trinity River plan in the subject line. Or call us at 512-239-6682.

Back to the top of the page Back to top