Effective backflow prevention helps keep your home’s water supply safe. Clean water for drinking, bathing, and other sanitary uses should always flow in only one direction: into the house. However, if certain circumstances cause a sudden pressure drop in the municipal water system — such as a major pipe rupture or the need to open multiple fire hydrants at once — the flow of water throughout your household plumbing system may be siphoned in the reverse direction. It’s known as backflow.
Why Backflow Happens
Powerful suction produced by municipal water flowing backward may draw unsafe water into your home’s water supply lines from a number of common sources called cross-connections. Sprinkler systems, pools, fire sprinklers, outdoor fountains, or fish ponds — or even something as simple as garden hoses retaining rancid water — are all potential origins of backflow contamination. You definitely don’t want to be drinking or bathing in water originating from these sources.
How It’s Prevented
Backflow-prevention devices installed in the home are basically valves that permit water to flow only in one direction — the safe direction. To prevent polluted, unsafe water from being sucked backward into your home’s water supply, these devices are typically installed at household locations such as:
- Outdoor hose bibs
- Lawn-sprinkler supply line
- Main fire sprinkler pipe
- Heating system boiler
- Swimming pool supply line
- Water lines feeding outdoor fountains or ponds
- Various individual devices such as hand-held shower heads
What To Do Next
A full inspection by a qualified professional plumber can reveal cross-connections in the home where backflow could occur if the municipal water pressure dropped suddenly. The design of backflow-prevention valves varies according to the location or device where they may be installed. However, since events in the municipal supply that may trigger backflow generally occur without any warning, all backflow devices generally operate automatically and do not require action by residents to protect the home water supply.
The plumbing professionals at Aggressive Mechanical can provide more information about backflow prevention to protect your home from unsafe water.