What does the term "backsiphonage" refer to?

The term "backsiphonage" specifically refers to a situation where negative pressure occurs in a plumbing system, causing water to flow in the reverse direction. This can happen when there is a drop in pressure within the distribution system, often due to events like a broken water main, excessive water withdrawal from a nearby source, or even fire fighting activities that reduce pressure.

In this condition, contaminants from the surrounding environment or from connected fixtures can be sucked back into the clean water supply due to the created negative pressure. Therefore, understanding backsiphonage is crucial for preventing potential health hazards, as it poses a risk of contaminating potable water supplies. Being aware of how this phenomenon occurs helps inform safe plumbing practices and the design of backflow prevention systems, which are essential to maintain water quality and safety in municipal systems.