This Subpart and the laws providing for the creation and government of the levee districts and levee and drainage districts and their authority or power to levy and collect taxes and local contributions and to issue bonds shall not be repealed or modified to the detriment of the bonds authorized by this Subpart. This obligation not to repeal or modify these statutes is declared to be binding on the state and to be part of the contract of the bonds.
La. R.S. § 38:497