A. “Backflow” means the flow other than the intended direction of flow of any foreign liquids, gases or substances into the distribution system of a public water supply;

B. “Backflow prevention device” means a device (AWWA approved) to counteract back pressure or prevent back siphonage;

C. “Cross-connection” means any physical arrangement whereby a public water supply is connected, directly or indirectly, with any other water supply system, sewer, drain, conduit, pool, storage reservoir, plumbing fixture or other device which contains or may contain contaminated waste, sewage, or other waste or liquids of unknown or unsafe quality which may be capable of imparting contamination to the public water supply as a result of backflow;

D. “Superintendent” means the superintendent of the Everett water department, or any staff member of the Snohomish health district or the state of Washington Department of Social and Health Services qualified in protection of municipal water quality. (Prior code § 14.18.010.)