Backflow Prevention Devices are a crucial part of any lawn sprinkler system. To understand what a backflow prevention device is, there are some key terms that need to be understood.
Cross Connection is any connection between a potable (drinkable) water system and any system containing non-potable water, pollutants or toxins. An example of where a cross-connection would exist is the piping between consumers’ water systems and an auxiliary water system, a cooling system, or an irrigation/lawn sprinkler system.
Backflow is defined as any unwanted reversal of the flow of liquids, solids, or gases in a piping system. Backflow in an irrigation application is when water from the sprinkler system travels “upstream” through the pipes and enters the potable water system through a cross-connection.
Back Pressure is when the pressure downstream of the backflow devices exceeds the supply (or upstream) pressure. This can occur if the supply pressure is reduced, or if the pressure downstream is increased.
Back Siphonage occurs when a vacuum is created upstream of the backflow device, and water is literally sucked back up the system. Back siphonage can happen when the water supply is stopped due to a water main break or nearby fire hydrant use.
Backflow Prevention Device
Backflow Prevention Devices are mechanisms designed to prevent contaminants from entering the potable water system in the event of back pressure or back siphonage.
Why we need backflow protection
Most homes have only one system for both potable and irrigation water, instead of two separate systems to avoid the risks associated with a cross-connection. Because there is no separation, there is a risk that everything running through your sprinkler system (fertilizers, pesticides and herbicides, as well as anything that has seeped into the ground, such as animal waste, lawn chemicals) will backflow into your potable water system. The only way to prevent this from happening is the use of some type of backflow prevention device. The shutoff valves included in sprinkler systems are not enough to prevent backflow.
Backflow Prevention Devices have internal parts that can wear out and not function properly. These devices also have a ‘life span’, like other components of your sprinkler system, and will need to be repaired or replaced. The best way to determine if your backflow is operating properly is to have it tested by our Licensed Backflow Tester. Greenworld offers this service to all of our customers.