What is backflow?

Backflow is used to describe a condition that occurs when a difference in water pressure causes contaminants to enter the municipal water distribution system and/or the customer’s water piping.  The two most common kinds of backflow conditions are back
, where a device such as a pump forces higher pressure water and contaminates into the distribution system against the existing system pressure, and back siphoning, where a sudden
loss of system pressure (due to a water main break or heavy demand) causes
contaminates to be drawn into the distribution system.  Backflow prevention assemblies are designed
to sense these conditions and react to prevent contamination.


Show All Answers

1. What is backflow?
2. How does ONWASA protect the public water system against Backflow contamination?
3. Why do I have to install a blackflow assembly if my neighbors do not have them?
4. How can I tell if water/sewer service is available to my property?
5. If I don't have direct access to a water or sewer main, will ONWASA extend a water and/or sewer main to my property?
6. Why are there blue or green marks and/or flags in my yard?