(1) An irrigation district may increase the number of its board of directors from three to five members when:
(a) In the judgment of the board of directors, it is necessary or beneficial to the welfare of the district; or
(b) Fifty or more qualified electors within the district file with the board a petition requesting an election for the purpose of increasing the number of directors.
(2) Upon the determination of the board or upon the filing of a petition requesting the increase, the board shall submit the question to the district electors at the next regular election or at a special election ordered by the board for such purpose. At the same election, two persons shall be elected to serve as directors if the electors, by a majority of votes cast at the election, increase the number of the board.