Which of the following describes backsiphonage?

Backsiphonage is accurately described as a condition where backflow occurs due to negative pressure in the water system. This phenomenon typically arises when there is a significant drop in pressure in the main water supply line, which can be caused by events such as a water main break or excessive water usage, creating a vacuum that pulls water from another source into the drinking water supply. This can lead to potential contamination, as unwanted substances can enter the potable water.

Understanding backsiphonage is essential for water treatment operators because it highlights the importance of maintaining proper water pressure and implementing safeguards, such as air gaps or backflow preventers, to protect the public water supply from contamination.