Tex. Loc. Gov't Code § 252.023
The referendum provisions prescribed by Section 252.045 do not apply to expenditures that are payable:
(3) by time warrants unless the amount of the time warrants issued by the municipality for all purposes during the current calendar year exceeds:
Acts 1987, 70th Leg., ch. 149, Sec. 1, eff. Sept. 1, 1987.
Amended by Acts 1991, 72nd Leg., ch. 109, Sec. 1, eff. Aug. 26, 1991.