Texas Water Code
§ 26.179 — DESIGNATION OF WATER QUALITY PROTECTION ZONES IN CERTAIN AREAS
WA § 26.179Title 2. WATER ADMINISTRATION · Part D. WATER QUALITY CONTROL · Ch. 26. WATER QUALITY CONTROL · Art. E. AUTHORITY OF LOCAL GOVERNMENTS
Statute text
View on source(a)In this section, "water quality protection" may be achieved by:
(1)maintaining background levels of water quality in waterways; or
(2)capturing and retaining the first 1.5 inches of rainfall from developed areas.
(b)For the purpose of Subsection (a)(1), "maintaining background levels of water quality in waterways" means maintaining background levels of water quality in waterways comparable to those levels which existed prior to new development as measured by the following constituents: total suspended solids, total phosphorus, total nitrogen, and chemical and biochemical oxygen demand. Background levels shall be established either from sufficient data collected from water quality monitoring at one or more sites located within the area designated as a water quality protection zone or, if such data are unavailable, from calculations performed and certified by a registered professional engineer utilizing the concepts and data from the National Urban Runoff Program (NURP) Study or other studies approved by the commission for the constituents resulting from average annual runoff, until such data collected at the site are available. Background levels for undeveloped sites shall be verified based on monitoring results from other areas of property within the zone prior to its development. The monitoring shall consist of a minimum of one stage (flow) composite sample for at least four storm events of one-half inch or more of rainfall that occur at least one month apart. Monitoring of the four constituents shall be determined by monitoring at four or more locations where runoff occurs. A minimum of four sample events per year for each location for rainfall events greater than one-half inch shall be taken. Monitoring shall occur for three consecutive years after each phase of development occurs within the Water Quality Protection Zone. Each new phase of development, including associated best management practices, will require monitoring for a three-year period. The results of the monitoring and a description of the best management practices being used throughout the zone shall be summarized in a technical report and submitted to the commission no later than April 1 of each calendar year during development of the property, although the commission may determine that monitoring is no longer required. The commission shall review the technical report. If the performance monitoring and best management practices indicate that background levels were not maintained during the previous year, the owner or developer of land within the water quality protection zone shall:
(1)modify water quality plans developed under this section for future phases of development in the water quality protection zone to the extent reasonably feasible and practical; and
(2)modify operational and maintenance practices in existing phases of the water quality protection zone to the extent reasonably feasible and practical. Water quality monitoring shall not be required in areas using the methodology described by Subsection (a)(2).
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Legislative history
Acts 2023, 88th Leg., R.S., Ch. 644 (H.B. 4559), Sec. 278, eff. September 1, 2023. Acts 2025, 89th Leg., R.S., Ch. 986 (S.B. 766), Sec. 80, eff. September 1, 2025.