Dive into Success with Ken Tesh's 2025 Water Distribution Operator Exam 1 Practice – Make Waves in Your Career!

A check valve is a critical device used to prevent backflow in a water distribution system. It functions by allowing fluid to flow in only one direction, effectively blocking reverse flow that could cause contamination of the clean water supply. This is essential in maintaining water quality and safety, as backflow can introduce harmful substances and pollutants into the drinking water system.

Check valves operate mechanically, opening when the pressure from the supply side exceeds the pressure on the outlet side, thereby allowing flow. If the pressure changes, such as during a system failure or a sudden drop in pressure, the check valve closes automatically, preventing any backflow from occurring.

While other methods like air gaps can also prevent backflow effectively, a check valve is often preferred in many systems for its simplicity and reliability in various configurations. It does not require constant monitoring or adjustment, making it a widely used solution in maintaining the integrity of water distribution systems.