Cal. Veh. Code § 35791

The Department of Transportation and any local authority may, with respect to such highways as may be agreed upon under their respective jurisdictions which traverse any area within the boundaries of the local authority, contract for the issuance by either authority of a single permit authorizing the operation or movement of a vehicle or a combination of vehicles or special mobile equipment in the same manner as if each authority had issued separate permits pursuant to Section 35780.