Cal. Health and Safety Code § 6484

The members of the board elected at the election as a result of which the district was organized or, if the district is reorganized under this part, then the five members in office at the time of the reorganization shall, at their first meeting, or as soon thereafter as may be practicable, so classify themselves, by lot, that they shall go out of office as follows: (a) Two shall serve until the election held in the first even-numbered year after the year in which the district is formed or reorganized, and until the election and qualification of their successors. (b) Three shall serve until the second even-numbered year after the district is formed or reorganized, and until the election and qualification of their successors. Notwithstanding any other provision of this part, except in districts that consolidate the election of directors with the direct primary election, the terms of office of members of the board in all districts existing on January 1, 1967, shall be determined as provided in Section 10507 of the Elections Code, and the terms of office of members of the board in all new districts shall be determined as provided in Section 10505 of the Elections Code.