(a) TCEQ rules shall:
  (1) comply with the requirements of the Clean Water Act, 33 United States Code Annotated, §§1251 et seq, and implementing regulations at Code of Federal Regulations, Title 40, which include establishing surface water quality standards in order to protect designated uses of coastal waters, including the protection of uses for water supply, recreational purposes, and propagation and protection of terrestrial and aquatic life, and establishing water-quality-based effluent limits, including toxicity monitoring and specific toxicity or chemical limits as necessary to protect designated uses of coastal waters;
  (2) provide for the assessment of water quality on a coastal watershed basis as required by the Texas Water Code, §26.0135(d);
  (3) to the greatest extent practicable, provide that all permits for the discharge of wastewater within a given watershed or region of a single watershed contain the same expiration date in order to evaluate the combined effects of permitted discharges on water quality within that watershed or region;
  (4) identify and rank waters that are not attaining designated uses and establish total maximum daily pollutant loads in accordance with those rankings using scientifically valid models calibrated and validated with monitored data and with public input from affected stakeholders; and
  (5) require that increases in pollutant loads to coastal waters shall not:
    (A) impair designated uses of coastal waters; or
    (B) result in degradation of coastal waters that exceed fishable/swimmable quality except in cases where lowering coastal water quality is necessary for important economic or social development.
(b) Discharge of municipal and industrial wastewater in the coastal zone shall comply with the following policies.
  (1) Discharges shall comply with water-quality-based effluent limits.
  (2) Discharges that increase pollutant loadings to coastal waters shall not impair designated uses of coastal waters and shall not significantly degrade coastal water quality unless necessary for important economic or social development.
  (3) To the greatest extent practicable, new wastewater outfalls shall be located where they will not adversely affect critical areas.
(c) The TCEQ shall comply with the policies in this section when adopting rules and authorizing wastewater discharges under Texas Water Code, Chapter 26.
(d) The TCEQ shall consult with the Texas Department of State Health Services when reviewing permit applications for wastewater discharges that may significantly adversely affect oyster reefs.

Source Note: The provisions of this §26.21 adopted to be effective October 6, 2004, 29 TexReg 9407; amended to be effective October 29, 2006, 31 TexReg 8840; transferred effective December 1, 2022, as published in the Texas Register October 28, 2022, 47 TexReg 7301; amended to be effective July 10, 2023, 48 TexReg 3671