A backflow issue exists if a lawn irrigation sprinkler malfunctions and a water main breaks at the same time. When the water pressure drops, it creates a vacuum that sucks some water, which may be contaminated, into the water supply.

A backflow issue exists if a lawn irrigation sprinkler malfunctions and a water main breaks at the same time. When the water pressure drops, it creates a vacuum that sucks some water, which may be contaminated, into the water supply.