(a) The commission may:(1) agree with a county to operate, maintain, or contribute to the maintenance costs of a project if the agreement is not inconsistent with the rights of the bondholders;(2) lease a project from a county under terms that are agreed to by the county and that are not inconsistent with the bond instrument; and(3) declare or operate all or part of a project as part of the state highway system only if the property and contract rights in the project and in the bonds are not unfavorably affected.(b) The project shall become part of the state highway system and the commission shall maintain the project free of tolls when:(1) the principal and interest due on the bonds are paid; or(2) a sufficient reserve to pay the principal and interest due on the bonds until maturity has been deposited in an irrevocable trust fund for the benefit of the bondholders. Acts 1995, 74th Leg., ch. 165, Sec. 1, eff. Sept. 1, 1995.