Tex. Spec. Dist. Local Laws Code § 11007.208

Without depriving this state of its power to regulate and control the rates, fees, and charges assessed for water sold and waste collection and treatment services provided by the district, the state pledges to and agrees with the holders of district bonds that the state will not exercise its power to regulate and control the rates, fees, and charges in any way that would impair the rights or remedies of the holders of the bonds.