California Code, Health and Safety Code - HSC § 13848

(a) If a majority of the voters voting upon the question at a general district or special election are in favor, a district that has an appointed district board shall have an elected district board or a district that has an elected district board shall have an appointed district board.

(b) The district board may adopt a resolution placing the question on the ballot. Alternatively, upon receipt of a petition signed by at least 25 percent of the registered voters of the district, the district board shall adopt a resolution placing the question on the ballot.

(c) If the question is submitted to the voters at a general district election, the notice required by Section 12112 of the Elections Code shall contain a statement of the question to appear on the ballot. If the question is submitted to the voters at a special election, the notice of election and ballot shall contain a statement of the question.

(d) If a majority of voters voting upon the question approves of changing from an appointed district board to an elected district board, the members of the district board shall be elected at the next general district election. If a majority of voters voting upon the question approves of changing from an elected district board to an appointed district board, members shall be appointed to the district board as vacancies occur.