CA Gov't Code Section 53109

Every local public agency within its respective jurisdiction shall establish and have in operation by December 31, 1985, a basic system as provided in this article, or be part of such a system.

The establishment of such systems shall be centralized to the extent feasible. Nothing in this article shall be construed to prohibit or discourage in any way the formation of multijurisdictional or regional systems, and any system established pursuant to this article may include the territory of more than one public agency or may include a segment of the territory of a public agency.