There shall be a Board of Zoning Appeals consisting of five (5) members who shall be electors of the City, who are not employed by the City and hold no other office of the City except on the Board of Site Arrangement. The members shall be selected by the Council for overlapping terms of five (5) years, so arranged that one (1) member's term shall expire on July 1st of each year. Alternate members may be appointed as determined by Council. The Board shall adopt its own rules and elect its own officers annually. It shall have all the power, authority and duty conferred upon it by ordinance.