What is a cross-connection? It is any connection between your drinking water and an unapproved source of water or any other contaminant. With a cross-connection, your drinking water can become contaminated when a backflow condition occurs. So, what is backflow? Backflow is when the water in your pipes (the pipes after the water meter) goes backward (the opposite direction from its normal flow). There are two situations that can cause the water to go backward (backflow): Backpressure – the pressure in your pipes is greater than the pressure coming in; and, Backsiphonage – a negative pressure in one of the pipes.
What is considered a potential hazard? ANY possibility of pollutants, contaminants, and system or plumbing hazards is considered a potential hazard. Examples may include: underground sprinklers utilizing potable water, water softener, swimming pool, etc. Putting the garden hose in a swimming pool to fill it; putting a garden hose in a pet's water bucket or fish tank can unwittingly create a cross-connection. So you may ask …What's the big deal? Well, the big deal is that backflows due to cross connections can cause sickness and death.
In order to protect the City of West Richland water supply the City, in accordance with the Washington Administrative Code (WAC) 246-290-490, established a Cross-Connection Control Program through Ordinance 7-08, codified in the West Richland Municipal Code 13.50.
These state and local laws require the City to have all premises surveyed by a licensed cross connection specialist to assess any hazards that may be present. We may protect the City water supply by having a premise owner install a backflow assembly. In most cases we rely on "in-premise fixture protection", as we do on your underground sprinkler system. In-premise fixture protection protects the water users as well as the City water system. In rare instances we use "premise isolation" to completely separate the water system from any possible cross connections. Premise isolation protects the City water system but not the water users in that premise and is used when frequent plumbing changes may endanger the water system.
For more information, you may also contact the Washington State Department of Health web site www.doh.wa.gov/ehp/dw/default.htm