All water utilities have a responsibility to provide water to their customers that meet quality standards. Cross-connections within the customer's plumbing system or within the utilities distribution system can cause contamination of our water's system. A cross-connection is any actual or potential physical connection, between a potable water (drinking water) system and any source of non-potable liquid, solid, or gas that could contaminate the potable water supply by backflow. Backflow is an undesirable reversal of water flow or other substances into the public water system or consumer's potable water system.
The City of Moses Lake Water Division administers a cross-connection program that requires backflow preventers on water services serving properties that have potential for high health hazards as listed in Table 9 in the State WAC 246-290-490(4)(b). Backflow prevention assemblies are installed to prevent backflow of contaminates into potable water through cross-connections. Cross-connection control within the property lines of a premise is the responsibility of the property owner. In accordance with the State WAC 51-56-0603.3.3, the premise owner or responsible person shall have a backflow prevention assembly tested by a Washington State Department of Health certified backflow assembly tester at least once per year.
Video: American Backflow Prevention Association.