(2) The board of trustees of a metropolitan water district may not collect property tax revenue in a tax year beginning on or after January 1, 2015, that would exceed the certified tax rate under Section 59-2-924 unless:

1. (a) the members of the board of trustees are all elected officials; or

2. (b) the proposed tax levy has previously been approved by:

   1. (i) a majority of the metropolitan water district voters at an election held for that purpose on a date specified in Section 20A-1-204; or
   2. (ii) the legislative body of each municipality that appoints a member to the board of trustees under Section 17B-2a-604.