Ever see one of the above pictured beauties alongside a road or on the side of a home? They come in various sizes depending on the amount of water flow that they are meant to handle. They are called “Backflow Preventers” (aka: Backflow Prevention Assemblies).
What type of water flows through them - drinkable or irrigational ?
What flows through is what is known as piped “Potable Water”. This is the “field” sanitation standard name which defines "Potable Water" as water that meets the quality standards prescribed and identified in the U.S. Public Health Service Drinking Water Standards. In-other-words, “potable water” is known as water which is approved for drinking purposes by the State and/or the local authority having jurisdiction in your area.
Are there any laws that protect the consumer?
The Federal Water Pollution Control Act of 1948 was the first major U.S. law to address water pollution. However, growing public awareness and concern for controlling water pollution led to sweeping amendments in 1972. As amended in 1972, the law became commonly known as the Clean Water Act (CWA).
The CWA was followed by the Safe Drinking Water Act (SDWA) that was passed by Congress in 1974. The SDWA placed the responsibility of local governments and water authorities to protect the public’s health by regulating and purifying the nation's public drinking water supply.
What is Backflow?
A Backflow itself is an “undesirable reversal” of the flow of non-potable water or mixtures of water and other undesirable pollutants and/or substances that flow back into the public/consumers potable (drinkable) water system.
There are two types of Backflow... (1) Backpressure Backflow and (2) Back Siphonage…
(1) Backpressure Backflow: is caused by a downstream pressure that is greater than the upstream potable water supply pressure in a public water system and/or at a residential potable water system. This Backpressure reversal in the water flow can result from (a) an increase in downstream pressure or (b) from a reduction in the upstream potable water supply pressure, or a combination of both. A reduction in potable water supply pressure can occur whenever the amount of water being used exceeds the amount of water being supplied, such as during water line flushing, fire hydrant use (ie: during fire fighting) or any break in the water main lines.
(2) Back Siphonage: is backflow caused by a negative or reduced pressure in the potable water supply flow. When pressure drops, a vacuum is created allowing water to siphon in the reverse flow. This can cause non-potable and/or polluted water to back-up into the drinking water supply line/pipes.
How can one stop a backflow from happening?
The municipality you live in or work at needs to install a “backflow preventer” devise (aka: backflow prevention assembly) for any potable water supply.
The degree/size of the potential hazard will determine which type and size of assembly or device that must be installed at a given location.
At your homestead (ie: place of residence), it is recommended that the homeowner also install a “backflow preventer” that intercepts the municipal potable water supply to your home. This for the purpose of having an extra barrier of protection.
If potable water supplied is at a permanent place of employment (ie: buildings, hospitals, schools etc.), the backflow preventer/assembly needs to be approved by the Occupational Safety and Health Administration (OSHA).
Note: Keep-in-mind that without any type of “back flow preventer” assembly installed, any amount of backflow can contaminate that immediate areas drinkable/potable water supply.
What is a backflow preventer?
The backflow preventer is an assembly device that prevents your drinkable water system from becoming contaminated from water flowing backwards into the public water supply lines. A backflow preventer is installed where the water main is routed into your home or place of employment.
In regards to residential and commercial use, it is also a good idea to install a backflow preventer if you have a sprinkler system. For this application, the backflow preventer would be installed prior to the main sprinkler line feed which as-you-know then goes thru the PVC pipes that feed the sprinkler heads.
Other simpler measures to take.
In addition to installing a backflow prevention assembly and/or making sure that one is installed at your place of residency, a homeowner can install a Hose Bibb Vacuum Breaker.
The hose bibb vacuum breaker is screwed onto and/or attached to your standard exterior water faucet/spigots. It is also known as an “anti-siphon” device. This simple low-cost gadget prevents unsanitary water from being pulled back from a garden hose. This reverse flow would cause the “check” in the hose bibb vacuum breaker to engage, therefore stopping any backflow at the spigot and not contaminating your drinking water system. Hose bibb vacuum breakers are usually made of brass, are durable and will provide years of reliable use.
Oscar Castillo : BROKER - REALTOR® (San Diego, CA)