What is backflow in the context of water supply systems?

Backflow in the context of water supply systems refers to the situation where water that has already moved through the distribution system flows back into the public supply from another source, which can potentially lead to contamination. This typically occurs due to changes in pressure within the system, such as during maintenance or a break in the water line, which may cause a reversal of the normal flow of water.

Understanding backflow is crucial for maintaining water quality and safety, as it poses risks of contamination from non-potable sources, such as irrigation systems or industrial processes. Proper backflow prevention methods, such as installing backflow preventers and air gaps, are essential in water supply systems to protect the health of the public and ensure the integrity of the water supply network.