Tex. Water Code § 51.318: CHARGES FOR MAINTENANCE EXPENSES.

(a) If maintenance charges are based on the quantity of water used, a fixed minimum charge may be made on all land, water connections, or other service entitled to receive and use water. An additional charge may be made for the use of more water than that covered by the minimum charge.

(b) The board may install proper measuring devices or require that they be installed.

Acts 1971, 62nd Leg., p. 327, ch. 58, Sec. 1, eff. Aug. 30, 1971.