As an alternative to serving as the commissioners of the authority, the governing body of any county or city, at the time of the adoption of a resolution or ordinance pursuant to Section 52030 or at any time thereafter, may appoint other persons as commissioners of the authority. The governing body shall, in this case, specify the number and appointment of commissioners, except that there shall be not less than three commissioners. The governing body shall prescribe the powers and functions delegated to commissioners appointed under this article.