Cal. Elec. Code § 7205
Notwithstanding this article, each county central committee by resolution may provide for the election of all or a portion of central committee members to represent individual central committee districts. The member shall reside in the district he or she represents but shall be elected at large within the Assembly district in which the county central committee district he or she represents is located.
The county central committee shall reapportion itself at least every 10 years, prior to the June primary election of that year. Each district shall be apportioned on the basis of the number of registered Democrats for the June primary in each even-numbered year, with no more than a 10-percent deviation from the average. Each district shall be compact, contiguous, and utilize any natural and neighborhood boundaries. The district boundaries shall not cut across any district lines of a precinct as drawn by the elections official for the last general or consolidated election.
Ca. Elec. Code § 7205