Tex. Water Code § 5.175

(a) All information, documents, and data collected by the commission in the performance of its duties are the property of the state.

(b) Except as provided by Subsection (c) of this section, records, reports, data, or other information obtained relative to or from sources or potential sources of discharges of water pollutants shall be available to the public during regular office hours.

(c) If a showing satisfactory to the executive director is made by any person that those records, reports, data, or other information, other than effluent data, would divulge methods or processes entitled to protection as trade secrets, the commission shall consider those records, reports, data, or other information as confidential.

(d) This chapter may not be construed to make confidential any effluent data, including effluent data in records, reports, or other information, and including effluent data in permits, draft permits, and permit applications.

(e) Records, data, or other information considered confidential may be disclosed or transmitted to officers, employees, or authorized representatives of the state or of the United States with responsibilities in water pollution control. However, this disclosure or transmittal may be made only after adequate written assurance is given to the executive director that the confidentiality of the disclosed or transmitted records, data, or other information will be afforded all reasonable protection allowed by law by the receiving officer, employee or authorized representative on behalf of, and under the authority of, the receiving agency or political entity.

(f) The executive director may not disclose or transmit records, data, or other information considered confidential if he has reason to believe the recipient will not protect their confidentiality to the most reasonable extent provided by law.