Ark. Code Ann. § 14-186-404: Powers generally

Any two (2) or more municipalities, any two (2) or more counties, or any one (1) municipality or more together with any one (1) county or more in the State of Arkansas, or in an adjoining state where a navigable river forms the boundary between the states and the county or municipality in the other state lies approximately opposite the county or municipality within the State of Arkansas may join to construct, purchase, establish, equip, and operate a port within or without the corporate limits of any such municipality and within or without the boundaries of any such county, as they are defined and laid out, or as they may in the future be enlarged, as provided in this subchapter.