It is unlawful for any person, firm, or corporation, at any time to make or maintain or cause to be made or maintained, temporarily or permanently, for any period of time whatsoever, any cross- connection between plumbing pipes or water fixtures being served with water by the city water department and any other source of water supply or to maintain any sanitary fixture or other appurtenances or fixtures which, by reason of their construction, may cause or allow backflow of water or other substances into the water supply system of the city and/or the service of water pipes or fixtures of any consumer of the city.
(Ord. 88-11 § 1 (part))