La. Stat. tit. 33 § 9039.26
It is hereby determined that the creation of the district and the carrying out of its public functions and corporate purposes is, in all respects, a public and governmental purpose for the benefit of the people of the state, and for the improvement of their health, safety, welfare, prosperity, and security, and that said functions and purposes are public purposes and that the district will be performing an essential governmental function in the exercise of the powers conferred upon it by this Chapter. All obligations authorized to be issued by the district pursuant to the provisions of this Chapter, together with interest thereof, income therefrom, and gain upon the sale thereof shall be exempt from all state and local taxes.
La. R.S. § 33:9039.26