What does backflow refer to in regards to water supply?

Backflow refers specifically to the unwanted reversal of the flow of water, which can occur when there is a significant change in water pressure. This phenomenon can lead to non-potable (contaminated) water entering the potable (clean) water supply system. When pressure in the supply system drops due to various reasons, such as a burst pipe or increased water demand, water from places where it shouldn't flow—like irrigation systems, toilets, or industrial plants—can be siphoned back into the clean water supply.

Understanding this concept is crucial for food safety and public health because backflow can introduce harmful contaminants into drinking water, posing significant risks. Thus, it is vital for food managers to implement backflow prevention methods to safeguard the integrity of the water supply system for food preparation and service.