Tex. Nat. Res. Code § 51.297
Acts 1977, 65th Leg., p. 2439, ch. 871, art. I, Sec. 1, eff. Sept. 1, 1977.
Amended by Acts 1985, 69th Leg., ch. 923, Sec. 12, eff. Aug. 26, 1985;
Acts 1987, 70th Leg., ch. 208, Sec. 12, eff. Aug. 31, 1987.
Acts 2007, 80th Leg., R.S., Ch. 387 (S.B. 654), Sec. 9, eff. June 15, 2007.