La. Stat. tit. 33 § 4259
The governing body of any municipality which has heretofore issued or hereafter issues bonds payable from utility revenues under the provisions of this Sub-part or any other law may authorize the issuance of bonds for the purpose of refunding, extending and unifying the whole or any part of the principal, interest and redemption premiums on the outstanding bonds. The refunding bonds may either be sold and the proceeds applied to or deposited in escrow for the retirement of the outstanding bonds, or may be delivered in exchange for the outstanding bonds. The refunding bonds shall be authorized in all respects as original bonds are herein required to be authorized, except that no election shall be necessary in the event the refunding bonds are sold at public sale after advertisement in the manner provided by R.S. 39:570 and the annual principal and interest on the refunding bonds is less than the combined annual principal and interest on the bond issue or issues being so refunded, extended and unified. The governing body, in authorizing the refunding bonds, shall provide for the security of the bonds, the sources from which the bonds are to be paid and for the rights of the holders thereof in all respects as herein provided for other bonds issued under the authority of this Sub-part. The governing body may also provide that the refunding bonds shall have the same priority of lien on the revenues pledged for their payment as was enjoyed by the bonds refunded.
La. R.S. § 33:4259