What the heck is a backflow and why do I care?
It is a condition where the water, or some other substance, in the plumbing of your building (residence,
business, whatever) or a cross connection with another plumbing system(irrigation, chemical tank, LP tank
etc.), flows backwards back into the city or county’s water system.
Cross Connections and Backflow Prevention
What is a cross-connection?
- A cross connection is a physical connection between a drinking water system and some other
environment which could allow a backflow of contaminants to enter the drinking water. This could be a
pipe connecting a customer’s drinking water system to the heating/cooling system, fire system or
What is a backflow?
- A backflow is an undesirable reverse flow of a substance (water or otherwise) through a cross
connection into the drinking water system. A backflow can contaminate either the customer’s drinking
water system within a building or the public drinking water system in the street. Backflows can be caused
in one of two ways: back-siphonage or back-pressure.
What is back-siphonage and its causes?
- Back-siphonage can occur when reduced pressure in the watermain allows a siphon to start and
contaminants to enter the main. Back-siphonage can be created when there is an interruption of the
water supply due to nearby fire-fighting, repairs or breaks in water supply mains.
What is a back-pressure backflow?
- Back-pressure backflows can occur when a system operating under a higher pressure than the pressure
in the watermain forces the contaminants into the drinking water. Back-pressure backflows can be
caused by high pressure pumps, temperature increases in boilers, elevated tanks or other pressure
What are some typical cross connections found in a residential home?
The most common types of cross connections found in the home include:
- Garden hose attached to a outside tap or hose bibb with the end of the hose connected to a pesticide
sprayer or left submerged in a ornamental pool
- Underground lawn watering (irrigation) system
- Laundry sink with submerged hose
- Handheld shower head immersed in water
- Hot water heating system
- Home fire protection system
- In-home water treatment (softener) system
- High pressure washer
What will a backflow preventer do for me?
- A properly installed and working backflow preventer will protect your family or business from
contaminants flowing backwards into your household drinking water piping.
What is a backflow preventer?
- A backflow preventer is a mechanical device that prohibits a backflow of contaminants from getting into
the drinking water. The principal types of testable backflow preventers used for medium to high hazard
processes include: reduced-pressure principle assemblies, double check valve assemblies and pressure
vacuum breaker assemblies. Non-testable devices used for low hazard processes include: residential
dual check valves and hose connection vacuum breakers.
What is the typical cost of purchasing a backflow preventer?
- The cost of a backflow preventer depends upon the type of preventer and the size of the preventer.
- Local codes will determine the type of device based on the application, i.e: residence or irrigation.
Contact WRC Management for a free estimate.
Testing Backflow Preventers
Why do backflow preventers have to be tested regularly?
- Backflow preventers have internal seals, springs, and moving parts that are subject to fouling, wear, or
fatigue. Therefore, backflow preventers have to be tested regularly with calibrated equipment to ensure
that they are functioning properly. Typically, backflow preventers are tested once each year.
Who is responsible for having a backflow preventer tested?
- Generally, the owner of the residence, building or property manager is responsible for having the
preventer tested. If the backflow preventer belongs to the tenant then the tenant is responsible for
having the preventer tested.
Who can test backflow preventers?
- Only an individual who is a Certified Backflow Prevention Assembly Tester and has been certified by the
State of Florida is permitted to test backflow preventers.
I have received a letter stating that my backflow preventer is due for testing, what am I required to
- Contact a Certified Backflow Prevention Assembly Tester such as WRC Management to test the
What are the consequences for failing to comply with the testing request?
- Failure to comply with the notification may result in discontinuation of water service.
What is the typical of a backflow preventer test?
- The typical cost of testing a backflow preventer varies depending the quantity and size of the
device/devices to be tested.
Installing New Backflow Preventers
Will a backflow preventer affect my water pressure?
- Only minimally, essentially all backflow preventers cause some degree of pressure loss. The typical
pressure drop across a preventer depends upon the type, make, size and location of the device. Refer
to the manufacturers literature exact information.
Is a permit required when installing a backflow preventer?
- Any plumbing alteration related to the installation of a testable backflow preventer (RP, DCVA, & PVB)
may require a plumbing permit. For permit information or inquires contact your local municipality.