The maintenance, including necessary repairs, of all backflow prevention assemblies and cross connection control devices required by this chapter shall be the responsibility of the consumer, and failure to adequately maintain any required equipment shall be a violation hereof. All installations and repairs of such equipment shall be completed by a certified journeyman plumber or other agent of the owner, provided he is a certified backflow technician as provided in Section 13.20.090 in either case. (Ord. 91-02 § 7)