Upon receipt of a duly certified petition or a valid resolution calling for an election on the formation of a metropolitan municipal corporation, the board of commissioners of the central county shall fix a date for a public hearing thereon which shall be not more than sixty nor less than forty days following the receipt of such resolution or petition. Notice of such hearing shall be published once a week for at least four consecutive weeks in one or more newspapers of general circulation within the metropolitan area. The notice shall contain a description of the boundaries of the proposed metropolitan area, shall name the initial metropolitan function or functions and shall state the time and place of the hearing and the fact that any changes in the boundaries of the metropolitan area will be considered at such time and place. At such hearing or any continuation thereof, any interested person may appear and be heard on all matters relating to the effect of the formation of the proposed municipal metropolitan corporation. The commissioners may make such changes in the boundaries of the metropolitan area as they shall deem reasonable and proper, but may not delete any portion of the proposed area which will create an island of included or excluded lands, may not delete a portion of any city, and may not delete any portion of the proposed area which is contributing or may reasonably be expected to contribute to the pollution of any water course or body of water in the proposed area when the petition or resolution names metropolitan water pollution abatement as a function to be performed by the proposed metropolitan municipal corporation. If the commissioners shall determine that any additional territory should be included in the metropolitan area, a second hearing shall be held and notice given in the same manner as for the original hearing. The commissioners may adjourn the hearing on the formation of a metropolitan municipal corporation from time to time not exceeding thirty days in all. At the next regular meeting following the conclusion of such hearing the commissioners shall adopt a resolution fixing the boundaries of the proposed metropolitan municipal corporation, declaring that the formation of the proposed metropolitan municipal corporation will be conducive to the welfare and benefit of the persons and property therein and providing for the calling of a special election on the formation of the metropolitan municipal corporation to be held not more than one hundred twenty days nor less than sixty days following the adoption of such resolution.