Why Test?

Backflow Preventers protect our drinking water!

Water backflow preventers are installed to prevent bad water, from a business or residence, from getting back into the public water system.
They are installed between the clean and protected water that our city provides to our homes and businesses, and sources that can pollute and contaminate the water. 
These include fertilizers, pesticides, dyes, detergents, waste, and chemicals used in businesses, medical facilities, manufacturing, and industrial processes.  Basically, anything that can mix with the water after it leaves the control of the local water utility.

Causes of water reversal are commonly due to a loss of supply pressure from the public water system.  Many situations can result in a pressure drop, such as a water main break, a fire hydrant being opened, or even a planned shut-off of water by the local utility for scheduled maintenance. 

If backflow is not prevented, chemicals which have mixed with normally clean water, in a business or residence, can get sucked back into the public water system or your home, causing illness if the water is consumed, damage to the water piping system, and in extreme cases, even death.

City and Water Department backflow testing programs are intended to verify and maintain that backflow preventers remain in good working order after their initial installation.  Manufacturers and standards organizations recommend annual inspections of installed backflow preventers.
Plumbing codes have required the installation of these preventers for decades, they are often then ignored and assumed to be working.  But the internal components contain rubber and plastic and are subject to wear, age, corrosion, pressure, and temperature extremes.  The devices rarely exhibit any outward indication of failure. 
Most people assume that "if it isn't leaking, it must be okay."  But this is often untrue, hence the need for periodic testing programs.