Ala. Code § 11-81-172.1

Any county or incorporated municipality in the State of Alabama may issue revenue bonds under the provisions of this article not only for the purposes specified in Section 11-81-166, but also for the purpose of refunding the principal of any outstanding general or limited obligation warrants of any such county or incorporated municipality that were issued (directly or indirectly) for the purpose of financing the acquisition, improvement, enlargement, extension or repair of any waterworks system, gas system, electric system or sanitary sewer system or that were issued to refund any general or limited obligation warrant or warrants initially issued by such county or incorporated municipality (directly or indirectly) for the purpose of financing the acquisition, improvement, enlargement, extension or repair of any waterworks system, gas system, electric system or sanitary sewer system, whether or not such principal shall have matured at the time of such refunding, and for the combined purpose of refunding the principal of any such general or limited obligation warrants and any other purpose or purposes specified in said Section 11-81-166.