La. Stat. tit. 48 § 1305
Before any such consolidated district shall be finally created, the governing authority of the parish shall publish in the official journal of the parish at least once not less than fifteen days prior to the date of hearing a notice of its intention to create such district and fixing a date for the holding of a public hearing in which all persons interested may be heard on the question of the advisability of creating the district. Such notice of hearing shall set forth the proposed name and boundaries of the district, list the districts to be so consolidated, and set forth the rate and duration of taxes authorized to be levied in each such underlying district, and shall state the date, time and place fixed for the hearing. Following the creation of any such district, the resolution creating the district and setting forth the boundaries thereof shall be published one time in the official journal of the parish. Thirty days after such publication, the creation of the district shall become incontestable, and no court shall have any right to entertain litigation questioning the legality of the creation of such district.
La. R.S. § 48:1305