Backflow Prevention Assembly

[eriual]

Hello, We are new home owners and go a letter from the water district saying we needed to have the Backflow Prevention Assembly inspected. I was wondering what this is and if it is the same a water pressure regulator.

[HayZee518]

the backflow preventer is a horizontal or vertical "check valve" it allows flow in one direction but not the reverse. where is this fitting located?

[eriual]

It's in the front yard. It is part of the irrigation system I think.

[HayZee518]

ok, then the backflow preventer allows flow out to the lawn or irrigation pipes, but opens on backflow towards the house. it is also called an anti-siphon valve. it is suppose to prevent cross contamination to your house plumbing if there is a direct connection to your irrigation system