(a) A municipality possesses exclusive authority to annex territory located within its approved urban growth boundaries; therefore, no municipality may annex by ordinance or by referendum any territory located within another municipality's approved urban growth boundaries. Within a municipality's approved urban growth boundaries, a municipality may use any of the methods in chapter 51 of this title to annex territory; provided, that if a quo warranto action is filed to challenge the annexation, the party filing the action has the burden of proving that:

(1) An annexation ordinance is unreasonable for the overall well-being of the communities involved; or

(2) The health, safety, and welfare of the citizens and property owners of the municipality and territory will not be materially retarded in the absence of such annexation.

(b) In any such action, the action shall be tried by the circuit court judge or chancellor without a jury.

(c)

(1) Prior to a municipality annexing by ordinance territory outside its existing urban growth boundary whether the territory desired for annexation is within another municipality's urban growth boundary or a county's planned growth area or rural area, it must first amend the growth plan by having its desired change to the urban growth boundary submitted to the coordinating committee and then receive a recommendation for or against the amendment from the coordinating committee, the coordinating committee then must submit the proposed amendment with its recommendation to all the legislative bodies for approval. If the amendment to the growth plan is approved by the legislative bodies or by the dispute resolution panel, it is then submitted to the local government planning advisory committee for its approval. This amendment process must follow the procedure as outlined in § 6-58-104 and the criteria for establishing an urban growth boundary as delineated in § 6-58-106.

(2) As an alternative to a municipality annexing in a county's planned growth area or rural area by first amending the growth plan as described in subdivision (c)(1), a municipality may annex within a county's planned growth area or rural area, but the annexation must be by referendum only and not by ordinance. The municipality must follow the referendum process as provided for in §§ 6-51-104 and 6-51-105.