The conservancy shall commence to function upon the occurrence of either of the following events:
(a) Approval by a four-fifths vote of the governing bodies of the member agencies.
(b) Approval by a majority of the voters voting on the proposition of whether the conservancy should commence to function at an election called for that purpose by the Boards of Supervisors of Fresno and Madera Counties within those counties. The election may be consolidated with any other election within those counties.