CA Health & Safety Code § 40704.5 (2021)
2021 California Code|Health and Safety Code - HSC|DIVISION 26 - AIR RESOURCES|PART 3 - AIR POLLUTION CONTROL DISTRICTS|CHAPTER 6 - General Powers and Duties|Section 40704.5.

40704.5.  (a)  Notwithstanding any other provision of law, on and after July 1, 1994, the membership of the governing board of an air quality management district, including any district formed on or after that date, shall include (1) one or more members who are mayors, city council members, or both, and (2) one or more members who are county supervisors. (b)  The number of those members and their composition shall be determined jointly by the counties and cities within the district, and shall be approved by a majority of the counties, and by a majority of the cities which contain a majority of the population in the incorporated area of the district. (c)  The governing board shall reflect, to the extent feasible and practicable, the geographic diversity of the district and the variation of population between the cities in the district. (d)  The members of the governing board who are mayors or city council members shall be selected by the city selection committee if the district only contains one county, or a majority of the cities within the district if the district contains more than one county. The members of the governing board who are county supervisors shall be selected by the county if the district only contains one county or a majority of counties within the district if the district contains more than one county. (e)  If a district fails to comply with subdivisions (a) and (b), the composition of the governing board shall be determined as follows: (1)  In districts in which the population in the incorporated areas represents 35 percent or less of the total county population, one-fourth of the members of the governing board shall be mayors or city council members, and three-fourths shall be county supervisors. (2)  In districts in which the population in the incorporated areas represents between 36 and 50 percent of the total county population, one-third of the members of the governing board shall be mayors or city council members, and two-thirds shall be county supervisors. (3)  In districts in which the population in the incorporated areas represents more than 50 percent of the total county population, one-half of the members of the governing board shall be mayors or city council members and one-half shall be county supervisors. (4)  The number of those members shall be determined as provided in subdivision (b) and the members shall be selected pursuant to subdivision (d). (5)  For purposes of paragraphs (1) to (3), inclusive, if any number which is not a whole number results from the application of the term “one-fourth,” “one-third,” “one-half,” “two-thirds,” or “three-fourths,” the number of county supervisors shall be increased to the nearest integer, and the number of mayors or city council members decreased to the nearest integer. (f)  This section does not apply to a district if the membership of the governing board of the district includes both county supervisors and mayors or city council members on June 30, 1994. (Added by Stats. 1993, Ch. 961, Sec. 8. Effective January 1, 1994. Operative July 1, 1994, by Sec. 10 of Ch. 961.)