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Backflow Prevention & Cross Connection Control

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Backflow is the reversal of water’s normal direction of flow. When water passes through a water meter into a customer’s home or business it should not flow back into the County water main. If it does, the condition is referred to as “backflow.” Backflow prevention is keeping the unintentional reversal of water flow from occurring.


How Does Backflow Take Place?

pictureThere are two types of backflow conditions back pressure and back-siphonage.  The first is a back pressure that occurs when the pressure in the consumer's line is greater than the pressure in the public water system's supply line. Examples, when using well water, gray water, and rainwater pump to irrigate and being dually connected to the public water supply: pumping at a higher pressure creates backflow pressure, possibly pumping into the public supply.  The second is a back siphonage. This occurs when the pressure in the public water system drops and backflow occurs, causing water to flow backward in a reverse direction or back siphonage condition.  The backflow device is designed to prevent and protect our water system from both of these conditions.

Prevention of backflow is critical to a water utility because of the potential for contamination of the water system. In the absence of backflow prevention devices and assemblies, reversed water can be drawn back into the distribution system and it may be accessed by other users.

If a backflow incident results from industrial customers who may handle hazardous materials, the public system can become contaminated.

picture Cobb Water is serious about our mission to protect customers, water resources, and the environment. Our objective is to monitor assemblies and install devices which will prevent the water supply from becoming contaminated, even unintentionally. It is essential for the community to be aware of the harmful impact of backflow. Through education, we can reduce and prevent the occurrence of backflow.  Working with the public as a team, the Cobb County Water System will provide direction to medium and high-risk Cobb businesses on the installation of appropriate backflow prevention devices.