(1) A single county may create a regional mobility authority by adoption of an ordinance.
(2) A combination of contiguous counties may create a regional mobility authority by each county: Adopting an ordinance that provides for the county's participation in the regional mobility authority; and
(3) Entering into a joint agreement with the other participating counties that states the jurisdictional boundaries of the regional mobility authority.
(4) This section shall not limit additional contiguous counties or municipalities from becoming a member in the regional mobility authority as provided under § 27-76-203.