Tex. Government Code § 1471.028: USE OF SURPLUS SINKING FUND.

An amount remaining in the sinking fund after the principal of and interest on the bonds are fully paid may be used by a political subdivision:

(1) for the construction, maintenance, and operation of macadamized, graveled, or paved roads or turnpikes;

(2) to aid a purpose described by Subdivision (1); or

(3) for a permanent improvement authorized by law as determined by the officials of the political subdivision.

Added by Acts 1999, 76th Leg., ch. 227, Sec. 1, eff. Sept. 1, 1999.