Plumbing & Backflow Testing

What is a backflow Preventer?

A backflow prevention assembly or device is used to protect water supplies from contamination or pollution.

In most places this is the law, everywhere else it's just the smart thing to do. Almost everywhere the local authorities will dictate that certain types of backflow preventers may not be used with irrigation systems because they do not provide adequate protection. In some cases, the authorities will dictate the exact type of backflow preventer you MUST use.

Why do you need a backflow preventer?

In water supply and irrigation systems, water is normally maintained at a significant pressure to enable water to flow from the tap, shower etc. When pressure fails or is reduced as may happen if a water main bursts, pipes freeze or there is unexpectedly high demand on the water system, the pressure in the pipe may be reduced and may allow contaminated water from the ground, from storage of from other sources to be drawn into the system. To prevent such an occurrence, many regulatory regimes require there to be an air gap or mechanical backflow prevention assembly between the delivery point of mains water and local storage or use.

Your landscape has all kinds of nasty things in it that will make you sick or worse if you drink them. Thus irrigation water is considered a contaminant rather than just a pollutant. In your irrigation water there can be toxic chemicals (fertilizers, pesticides, etc.) and animal waste. These things can and WILL come back up your irrigation pipes and into your drinking water if you don't stop them. If you have a well they can go down your well and into everyone else's drinking water. If you are on a community water system they could go back up into the pipes and poison your neighbours.