Backsiphonage is the reversal of normal flow in a system caused by a vacuum or partial vacuum within the water supply piping. Backpressure is the reversal of normal flow in a system due to pressure higher than the supply pressure. This program is enforced by law. The program has only changed in the fact that it is now up to you, the property owner, to have your backflow preventers tested annually and repaired or replaced as necessary. It has become your responsibility to ensure safe drinking water for yourself, your family, your friends, your customers, your venders, for everyone.
Backflow situations can happen anywhere, anytime, and under any condition or circumstance.
These backflow preventers are the only thing preventing severe contamination in our potable water supply. Situations have occurred. Some have been quite severe. Ironically, the ordinary garden hose is the most common offender as it can be easily connected to the potable water supply and used for a variety of potentially dangerous applications.