What is a backflow?

Backflow is the undesired reversal of flow of water and/or other substance into the potable water supply, via a cross-connection, due to a change in pressure caused by either Backpressure or Back siphonage. Backpressure is a type of backflow condition that exists when the pressure in the downstream side of the customer’s piping system becomes elevated greater than the supply pressure at the potable water system. Back siphonage is a type of backflow condition that exists when the pressure in the potable water supply system becomes lower than atmospheric pressure (14.7 psi).

Show All Answers

1. I have low pressure. What should I do?
2. In the case of an emergency, how do I shut my meter off?
3. What is a manhole?
4. Why are fire hydrants painted different colors?
5. What is an air release valve (ARV)?
6. What is a backflow?
7. What is a cross connection?
8. How do I get my water shut off during an emergency?
9. Why do water suppliers need to control cross-connections and protect their public water systems against backflow?
10. What is a backflow preventer?
11. What is an air gap?
12. What is a reduced principle assembly (RP)?
13. What is a pressure vacuum breaker assembly (PVB)?
14. What is a double check valve assembly (DC)?
15. What is a residential dual check valve (RDC)?
16. Why do backflow preventers have to be tested periodically?
17. Where can I get more information about cross-connection control?
18. What is a lateral cleanout?
19. What is a private lateral?
20. Who is responsible for the maintenance of a private sewer lateral?
21. What can be wrong with a private sewer lateral?
22. How do I know if there is something wrong with my private sewer lateral?
23. How often should I perform maintenance on my private sewer lateral?
24. What are the consequences of not maintaining my private sewer lateral?
25. What are the types of manholes?
26. Why aren’t there any fire hydrants in my subdivision?
27. Why are there blue markers in the road by fire hydrants?
28. Why is there blue paint on the sidewalk or roadway?
29. Why do you install concrete pads on some valves and not others?
30. There is water outside my meter box. What do I do?
31. My meter box/lid is damaged. Who do I call to have it replaced?
32. What is the device on my meter in the box?
33. What is a water meter?
34. How does my water meter work?
35. If I have a high bill, is there a way I can check for a leak?
36. What is the most common misconception about water meters?
37. Who is responsible for my water meter?