Tex. Water Code § 26.178

All financial assistance from the board to a city having a population of 5,000 or more inhabitants shall be conditioned on the city submitting to the commission for review and in accordance with rules and submission schedules promulgated by the commission a water pollution control and abatement program as required by Section 26.177 of this code. The board may award grants from the research and planning fund of the water assistance fund to river authorities seeking such funds for purposes of performing regional water quality assessments described in Section 26.0135 of this code.