What is a backflow?
What is a backflow?
While you may have heard the terms “backflow” or “cross-connection”, you might not be quite certain what they mean or how they can affect us all. Understanding the dangers that can be caused by backflow can help us all work together to protect our water resources.
WHAT IS A CROSS-CONNECTION?
Basically, a cross-connection is any real or potential connection between the clean, public water supply and a source that can contaminate or pollute that water.
WHAT IS BACKFLOW?
Simply put, backflow occurs when a loss in water pressure (commonly due to a fire hydrant being opened, a water main break or simply abnormally high water usage) cause the water in your pipes to flow in the opposite direction. This occurrence could allow contaminated or polluted water to travel back into your drinking water.
Cross-connections can occur at both commercial and residential properties.
For commercial customers, cross-connections exist in many forms, from carbonated beverage machines and ice-makers, to fire sprinkler systems and x-ray machines. It is not uncommon for a commercial property to have multiple cross-connections at their facility.
On the residential side, the most common cross-connections occur with lawn irrigation, hydronic heating boiler supply, and fire sprinkler systems. Perhaps the most frequently present cross-connection is the common garden hose, which when submerged in water, creates a dangerous path for contaminates to enter your drinking water.
WHY MUST I HAVE MY BACKFLOW ASSEMBLY TESTED ANNUALLY?
A backflow assembly is a mechanical device, containing springs, internal seals and moving parts, similar to an automobile. Similar to a car, backflow assemblies need routine maintenance and are subject to parts wearing down or breaking. An annual backflow test is required to ensure that the backflow assembly is working properly to protect the drinking water for you and your neighbors.
Here is an excellent example of a cross connection. This is a photo taken by Backflow Solutions Inc showing a typical residential hydronic heating boiler supply.
The clear piping on the left is the water supply to the boiler from the residential piping (your homes drinking water supply). Then, we have a backflow preventer followed by the boiler feed valve. You can see the piping on the right side is pink in colour. This pink liquid is glycol and other chemicals inside the heating system. The only thing stopping these harmful chemicals from entering the rest of home’s water supply is a backflow preventer.
This clearly shows the importance of having your backflow device inspected and serviced on a regular basis.