(1)    Any territory, constituting one or more municipalities contiguous to a district may be annexed to and become a part of such district to all intents and purposes and with like effect as though originally included therein upon such terms and conditions as the board of directors of the district shall fix by ordinance adopted by the affirmative vote of two-thirds of the directors-elect, provided that before such ordinance becomes effective the same shall be accepted and ratified by the affirmative vote of a majority of the qualified electors entitled to vote and voting in a special election called and held for that purpose in each municipality proposed in such ordinance to be annexed to the district. Such ordinance shall be published and such election shall be noticed, held and conducted, as nearly as may be, in the manner provided by this chapter for the noticing, holding and conduct of elections upon the organization of a municipal power district, except that the returns of such election and the ballots therein shall be delivered to the clerk of the district. The results of said election shall be canvassed publicly by the directors of the district.

   (2)   Upon the annexation of any territory to any district, each municipality so annexed shall be attached to and become a part of the subdistrict to which it may be contiguous or proximate, as shall be determined and declared by ordinance or resolution adopted by the board of directors of the district, and shall so remain until such time as the board shall form and establish new boundaries for subdistricts.