What is backflow?

Backflow is the flow of water or other substances in the opposite direction of what is intended. For example, instead of water flowing from WaterOne's system into the home or business, water flows back to the public water system. Our system is pressurized to help ensure one-way flow into customer plumbing. However, during isolated pressure fluctuations, or occasionally during events that occur inside customer property, backflow can occur. Below are some tips to prevent a personal backflow event in your home or property.

Common Terms

  • Backflow is the reversal of normal water flow, caused by a sudden change in water pressure. Backflow can contaminate the water supply.
  • Backflow Prevention Assembly (BPA): A mechanism to prevent backflow.
  • Cross Connection: Any temporary or permanent connection between a public water system or consumer potable water system and any source or system containing non-potable water or other substances.
  • Potable Water: Drinking water
  • Air gap: A vertical, physical separation between the end of the water supply outlet and the overflow rim of a receiving vessel, such as the distance between a sink faucet and the top of the sink.

Tips for Preventing Backflow At Home

  • Never place a running hose in a tub or pool of water. If there were a pressure change in the system, backflow could occur.
  • Check to make sure all your toilets have modern anti-siphon valves installed.
  • Make sure all sink faucets have an air gap between the top of the sink and the bottom of the faucet. If you have a detachable spray head, never leave it sitting in a pool of water.
  • Check your outdoor spigots to see if it has an integrated vacuum breaker. If not, you can easily install a vacuum breaker device to your spigot to prevent backflow.

At this time, WaterOne doesn't require annual testing on residential irrigation system BPAs. However, we recommend that any state or local laws be followed that may require additional protection.

Learn more about backflow requirements for Commercial Customers.