Ala. Code § 11-81-14: Presumption as to Validity of Issuance, Sale, Etc.; Limitation Period for Actions to Contest Validity Thereof.

Any bonds reciting that they are issued pursuant to this chapter shall in any action or proceeding involving their validity be conclusively deemed to be fully authorized by this chapter and to have been issued, sold, executed, and delivered in conformity herewith and with all other provisions of statutes applicable thereto and shall be incontestable, anything in this chapter or in other statutes to the contrary notwithstanding, unless such action or proceeding is begun before or within 30 days after the day upon which the bonds are delivered and paid for.