Tex. Gov't Code § 1501.051
(a) The governing body of a municipality may appropriate the net revenue from any municipal public utility system, service, or enterprise, in the amount that the governing body determines is in the best interest of the municipality, to:
(b) A governing body that makes an appropriation under Subsection (a) must make the appropriation:
Added by Acts 1999, 76th Leg., ch. 227, Sec. 1, eff. Sept. 1, 1999.