In the event of any vacancy in the office of port commissioner, such vacancy shall be filled at the next general election, and in the interim the vacancy shall be filled by appointment by a majority vote of the remaining port commissioners, and if said port commissioners shall fail to make such appointment within thirty (30) days after such vacancy occurs, then such appointment shall be made by the county commissioners of the county in which the vacant commissioner district exists.
If there should be at the same time, such number of vacancies that there are not in office a majority of the full number of commissioners fixed by law, the county commissioners of the county of each district in which such vacancy exists shall within thirty (30) days of such vacancy make appointments to fill the vacancies ad interim through the next general election.