California Code, Public Resources Code - PRC § 5785.1

(a) In the case of a board of directors elected by divisions or from divisions, the board of directors shall adjust the boundaries of the divisions before November 1 of the year following the year in which each decennial census is taken.  If, at any time between each decennial census, a change of organization or reorganization alters the population of the district, the board of directors shall reexamine the boundaries of its divisions.  If the board of directors finds that the population of any division has varied so that the divisions no longer meet the criteria specified in subdivision (f) of Section 5785, the board of directors shall adjust the boundaries of the divisions so that the divisions shall be as nearly equal in population as possible.  The board of directors shall make this change within 60 days of the effective date of the change of organization or reorganization.

(b) In the case of a board of directors that has been appointed by more than one county board of supervisors or city council, the board of directors shall adjust the proportionate distribution of the appointments before November 1 of the year following the year in which each decennial census is taken.  If at any time between each decennial census, a change of organization or reorganization alters the population of the district, the board of directors shall reexamine the proportionate distribution of appointments.  If the board of directors finds that the population of the district has varied so that the distribution of appointments is no longer proportionate, the board of directors shall adjust the proportionate distribution of appointments accordingly.  The board of directors shall make this change within 60 days of the effective date of the change of organization or reorganization.  The county board of supervisors or city council shall appoint members to the board of directors as vacancies occur.