California Code, Public Utilities Code - PUC § 130259

(a) Not later than February 1, 1978, the commissions in Riverside County and San Bernardino County shall, and the commissions in Los Angeles County and Orange County may, in cooperation with the Department of Transportation, the multicounty designated transportation planning agency, public transit operators, the county, and the cities involved, establish local transportation zones and adopt guidelines for their establishment and operation.

(b) It is particularly important that the county, cities, and other local public entities be involved in establishing local transportation zones.

(c) In adopting the guidelines, the commission shall take into account, among other things, the geographical shape of proposed local transportation zones, economies of scale of transit systems, and established and projected subregional patterns of travel.

(d) The guidelines shall provide for a method of governing each local transportation zone; shall provide for the establishment of multicounty local transportation zones; and shall authorize each board, under specified conditions, to provide transit services itself, through joint powers agreement or any other cooperative arrangement, or by contract with a public transit operator or a private common carrier.