Cal. VEH § 21115

(a) If a local authority finds that a highway under its jurisdiction is located adjacent to, or provides access to, a golf course and between the golf course and the place where golf carts are parked or stored or is within or bounded by a real estate development offering golf facilities and is designed and constructed, so as to safely permit the use of regular vehicular traffic and also the driving of golf carts on the highway, the local authority may, by resolution or ordinance, designate the highway or portion of the highway for combined use and prescribe rules and regulations that shall have the force of law. No highway shall be so designated for a distance of more than one mile from the golf course if the highway is not located within a development or beyond the area of a development, provided, the finding of the local authority in this respect shall be conclusive. Upon the designation becoming effective it shall be lawful to drive golf carts upon the highway in accordance with the prescribed rules and regulations. The rules and regulations may establish crossing zones and speed limits and other operating standards but shall not require that the golf carts conform to any requirements of this code with respect to registration, licensing, or equipment, except that if operated during darkness the golf cart shall be subject to the provisions of Section 24001.5 regarding equipment.

The rules and regulations shall not be effective until appropriate signs giving notice thereof are posted along the highway affected.

A “real estate development offering golf facilities,” for purposes of this section, means an area of single-family or multiple-family residences, the owners or occupants of which are eligible for membership in, or the use of, one or more golf courses within the development by virtue of their ownership or occupancy of a residential dwelling unit in the development.

(b) For purposes of this section, a “golf cart” includes a low-speed vehicle.