A backflow prevention assembly consists of test cocks and back flow valves or shut-off valves. These work to prevent contaminated water from flowing back into the clean water supply that carries water for drinking, cooking and bathing.
How And Why Would Contaminated Water Flow Back Into The Main Water Supply
The water that you use for drinking and cooking has the same supply source as the water that is used for irrigation. When you water your garden, the water that collects at the sprinkler head contains pesticides and fertilizers that you’ve used in the garden. These contaminants could get drawn back into the home water supply by the process of back-siphoning or backflow. This can pollute the potable water leading to dangerous or even fatal consequences. Backflow preventers are designed to stop this reversal of water flow.
How Backflow Preventers Work
Different types of backflow preventers are designed to work differently but the principle remains the same.
Under normal conditions, the flap or the backflow valve stays open and in a relaxed position, so that the water can pass through easily. This flap is positioned below the gate of the assembly. If it happens that the water starts flowing in the reverse direction, the force of the flow raises this flap. The raised flap creates an obstruction that hampers the backward flow of the water. If the backflow gets prolonged, the higher water level forces the gate to shut down, creating a mechanical seal that blocks the place off and stops the flow of water.
When the flow starts reducing and there is no more risk of backflow, the gate goes back to its original position helped along by gravity. With the gate back in its lowered position, normal sewage flow is allows to go through again. The way it functions, it prevents the flow of contaminants such as fertilizers and pesticides into the drinking water supply. In the absence of such a device, the risk of contamination is very high.
For homeowners and property owners, installing a backflow preventer assembly is no longer a matter of choice. It is a compulsory requirement. Most city codes had made it a mandatory that property owners adhere to this requirement. Moreover, it is the responsibility of the owner to ensure that this is installed and also tested regularly. Regular testing is just as important to ensure that the assembly is working the way it should be and that the test cocks and back flow valves are not worn out or broken.
Need to get your backflow preventer tested? The professionals at Mr.Plumber are experienced with installing, testing and repairing backflow preventers.