What is backflow?

Backflow refers specifically to the unwanted reversal of the flow of water in a plumbing system. This phenomenon can occur due to changes in pressure within the piping system, which may result in contaminated water flowing back into clean water supplies. It poses a significant health risk because it can introduce pollutants or pathogens into potable water sources.

Understanding backflow is crucial for water system professionals because preventing it is essential for maintaining the safety and quality of the water supply. Effective measures, such as installing backflow preventers and maintaining pressure in the system, are employed to mitigate this risk.

The other options describe different processes related to water treatment and plumbing but do not accurately define backflow. For example, moving water through treatment facilities, filtering solid particles, and adding chemicals pertain to water treatment and purification processes, rather than the critical issue of reversed flow in a plumbing context.