La. Stat. tit. 33 § 130.11
Subject to the written approval of fifty-one percent in interest of the landowners of the proposed industrial area, parish governing authorities may establish industrial areas composed of territory wholly within the parish boundaries and without the boundaries of any municipality. Such areas may be designated only after the feasibility therefor has been established by land use studies conducted by parish planning commissions, parish development boards or other similar recognized authorities. Cooperation and assistance in the preparation and evaluation of such studies may be rendered by state agencies equipped to conduct such studies when requested to do so by any parish governing authority provided that where municipal boundaries are co-extensive with parish boundaries, the municipal governing authorities may establish industrial areas within the municipal boundaries.
La. R.S. § 33:130.11