Summary of Completed TMDLs and Implementation Plans
Summary of completed load allocations and plans to improve water quality in surface waters that do not meet one or more standards for their use, as identified in the state's Texas Water Quality Inventory and 303(d) List.
Table: Summary of Completed TMDLs and Implementation Plans (IPs)
(In alphabetical order by name of water body or region)
| TMDL Allocation | Implementation Plan | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| TMDL Project (Click on the project for more information.) Parameter—Segments |
Impairments Addressed in Project | Water Body Segments Addressed in Project | TCEQ Date of TMDL Adoption | TMDLs Adopted | EPA Date of Action on TMDLs |
TMDLs Approved | TCEQ Date of Approval for I-Plans |
TMDLs Addressed by I-Plan | ||
| Aquilla Reservoir Atrazine—1254 |
1 | 1 | Original 3/23/01; Revised 6/14/02 | 1 | 10/30/02 |
1 | 01/18/02 | 1 | ||
| Arroyo Colorado Legacy Pollutants: DDE, Chlordane, Toxaphene—2202 PCBs—2202A |
4 | 2* | 1/17/01 | 4 | 6/14/01 | 4 | 9/14/01 | 4 | ||
| Arroyo Colorado Legacy Pollutants: DDT, DDD, dieldrin, endrin, lindane, hexachlorobenzene, heptachlor, heptachlor epoxide—2202 |
8 | 1* | 07/25/03 | 8 | 05/13/04 | 8 | ||||
| Buffalo and Whiteoak Bayous Bacteria—1013, 1013A, 1013C, 1014, 1014A, 1014B, 1014E, 1014H, 1014K, 1014L, 1014M, 1014N, 1014O, 1017, 1017A, 1017B, 1017D, and 1017E |
23*^ | 23*^ | 04/08/09 | 23*^ | 06/11/09 | 23*^ | ||||
| Clear Creek Above and Below Tidal Chlordane—1101, 1102 |
2 | 2* | 1/17/01 | 2 | 6/14/01 | 2 | 9/14/01 | 2 | ||
| Clear Creek Above and Below Tidal Trichloroethane, Dichloroethane—1101, 1102 |
4 | 2* | Original 2/9/01; Revised 6/14/02 | 4 | 05/09/03 | 4 | 10/12/01 | 4 | ||
| Clear Creek Above Tidal TDS, chloride—1102 |
2 | 1* | 08/10/05; Revised 04/12/06 |
2 | 06/26/06 | 2 | 08/23/06 | 2 | ||
| Clear Creek and Tributaries Bacteria—1101, 1101B, 1101D, 1102, 1102A, 1102B, 1102C, 1102D, 1102E |
18*^ | 18*^ | 09/10/08 |
18*^ | 03/06/09 | 18*^ | ||||
| Colorado River Below E.V. Spence Reservoir Chloride, Total Dissolved Solids—1426 |
2 | 1 | 02/07/07 | 2 | 04/09/07 | 2 | 10/10/07 | 2 | ||
| Dallas Legacy Chlordane—805, 841 DDD, DDE, DDT, PCBs, Chlordane, Dieldrin, Heptachlor epoxide - 841A |
9 | 3 | 12/20/00 | 9 | 6/27/01 |
9 | 8/10/01 | 9 | ||
| E.V. Spence Sulfate, TDS—1411 |
2 | 1 | Original 11/17/00; Revised 6/14/02 | 2 | 05/09/03 | 2 | 8/10/01 | 2 | ||
| Fort Worth Legacy Chlordane—806, 829 DDE, PCBs, Chlordane, Dieldrin—806A DDE, PCBs, Chlordane, Dieldrin—829A PCBs—806B |
11 | 5 | 11/17/00 | 11 | 5/24/01 | 11 | 7/13/01 | 11 | ||
| Gilleland Creek Bacteria—1428C |
1 | 1 | 08/08/07 | 1 | 04/21/09 | 1 | ||||
| Guadalupe River Above Canyon Lake Bacteria—1806 |
1 | 1 | 07/25/07 | 1 | 09/25/07 | 1 | ||||
| Houston Ship Channel Nickel Nickel—1001, 1005, 1006, 1007, 1013, 1014, 1016, 1017, 2426, 2427, 2428, 2429, 2430, 2436 |
14 | 14 | Original 8/11/00; Revised 6/14/02 | 14 | 05/09/03 | 14 | 7/13/01 | 14 | ||
| Lake Austin DO DO—1403 |
1 | 1 | 11/17/00 | 1 | 12/05/01 EPA declined to take action on this TMDL |
0 | 7/13/01 | 1 | ||
| Lake O’ the Pines DO—0403 |
1 | 1 | 04/12/06 | 1 | 06/07/06 | 1 | 7/9/08 | 1 | ||
| Lake Worth PCBs—0807 |
1 | 1 | 08/10/05 | 1 | 10/13/05 | 1 | 08/23/06 | 1 | ||
| Lower Sabinal River nitrate-nitrogen—2110 |
1 | 1 | 08/10/05 | 1 | 10/13/05 | 1 | 08/23/06 | 1 | ||
| Lower San Antonio River Bacteria—1901 |
1 | 1 | 08/20/08 | 1 | 10/20/08 | 1 | ||||
| North Bosque River Nutrients (narrative)—1226, 1255 |
2 | 2 | 2/9/01 | 2 | 12/13/01 |
2 | 12/13/02 | 2 | ||
| Nueces Bay Zinc in Oyster Tissue—2482 |
1 | 1 | 11/01/06 | 1 | 12/15/06 | 1 | 10/24/07 | 1 | ||
| Orange County Watersheds Bacteria, Dissolved Oxygen, pH—0508, 0508A, 0508B, 0508C, 0511, 0511A, 0511B, 0511C, and 0511E |
17 | 9 | 06/13/07 | 17 | 08/28/07 | 17 | ||||
| Oso Bay Bacteria—2485 |
1 | 1 | 08/22/07 | 1 | 06/08/08 | 1 | ||||
| Petronila Creek Above Tidal Chloride, Sulfate, Total Dissolved Solids—2204 |
3 | 1 | 01/10/07 | 3 | 03/14/07 | 3 | 10/10/07 | 3 | ||
| Salado Creek DO—1910 |
1 | 1* | 10/12/01 | 1 | 08/08/03 | 1 | Creek is supporting the aquatic life use, so an IP is not needed. |
N/A | ||
| Upper San Antonio River Bacteria—1910, 1910A, 1911 |
3 | 3* | 07/25/07 | 3 | 9/25/07 | 3 | ||||
| Upper Oyster Creek Bacteria—1245 |
1 | 1 | 08/08/07 | 1 | 09/28/07 | 1 | ||||
| Upper Gulf Coast Oyster Waters Bacteria—2421, 2422, 2423, 2424, 2432, 2439 |
7^ | 7^ | 08/20/08 | 7^ | 02/04/09 | 7^ | ||||
| # of Impairments Addressed in Project | # of Water Bodies Addressed in Project | # TMDLs Adopted | # TMDLs Approved | # TMDLs Addressed by I-Plan | ||||||
| Totals | 143 Impairments | 83 water bodies | 143 TMDLs for 83 water bodies | 142 TMDLs for 82 water bodies | 61 TMDLs for 35 water bodies (17 Plans) |
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*More than one project addresses the water body or bodies.
^Due to a change in requirements from the EPA, the TCEQ now develops and reports one TMDL for each assessment unit considered in a project. An assessment unit is a further subdivision of a water quality segment. This change in EPA reporting requirements was made after the TCEQ's report of this project was completed; consequently, the number of TMDLs reported in the summary table is greater than the number shown in the title of the TMDL report.
Understanding How TMDLs Are Counted
The EPA requires one TMDL for each impairment listed in each water body. An impairment is the combination of the use that is affected (such as support of aquatic life) with the pollutant or condition of concern (such as mercury or low dissolved oxygen). For example, if Jones Creek was listed as not meeting the aquatic life use because of low dissolved oxygen concentrations, and not meeting the fish consumption use because of mercury in fish tissue, two TMDLs would be required for Jones Creek.
Prior to 2009, a water body was defined as a water quality segment. A segment is a geographic portion of a river, lake, or bay that has relatively homogeneous chemical, physical, and hydrological characteristics. A segment is assigned a unique number for the purpose of categorization and provides a basic unit for managing water quality. In some cases, a segment may be the same as the entirety of the water body; for example, a small lake may not be divided into multiple numbered segments.
In 2009, the EPA began requiring the state to develop a TMDL for each assessment unit within a project area. An assessment unit is a further geographic subdivision of a segment. For example, if Segment 0200 has bacteria concentrations higher than the allowable criteria, and Segment 0200 has five assessment units, the TCEQ will develop and report 5 TMDLs, when formerly it would have reported only one TMDL.
To be most efficient with resources of time and money, the TMDL Program may conduct one project that addresses the same pollutant in multiple water bodies, or may conduct a project that addresses multiple similar pollutants (such as three different pesticides) in one water body. So a single project may produce many TMDLs.
Federal law requires that the EPA take formal action to approve or disapprove any TMDLs adopted by the states. So, on any particular date, the number of TMDLs adopted by the Commission may differ from the number approved by the EPA. Similarly, there is a lag time between the completion of a TMDL and the Commission’s approval of the plan to implement the TMDLs. That means that the number of TMDLs and I-Plans will not usually match, since TMDLs and I-Plans are being completed all the time.

