La. Stat. tit. 38 § 454
The board of commissioners shall set aside and deduct out of the taxes, local contributions, and other revenues of the levee board or levee and drainage board, by preference over all other claims, an amount sufficient to pay the bonds as they mature, as provided in the resolution authorizing the issuance of the bonds, and the amount set aside shall be used to pay and discharge the bonds at maturity. This Subpart shall not be construed so that bonds issued under the provisions of this Subpart shall constitute a charge upon the revenues prior to the charge of any outstanding bonds, notes, or certificates of indebtedness heretofore issued by the levee district or levee and drainage district, pursuant to authority conferred by law, except that bonds issued under the provisions of this Subpart shall be accorded the same rank and priority in the application and distribution of the taxes and revenues which were originally accorded to the bonds, notes, or certificates of indebtedness paid, refunded, or refinanced.
La. R.S. § 38:454