Leonardo Da Vinci said it right, “Water is the driving force of all nature.”
The water that we drink or use has a significant impact on our health. According to WHO, eighty per cent of the diseases recorded worldwide are waterborne. That’s why we cannot afford to take any risk with the water we consume on a daily basis.
Water backflow is a dangerous situation that might occur in your main water supply and could cause complications. Does that name ring a bell?
Don’t fret if it doesn’t. We’ve got you covered with our informational article if you don’t know anything about backflow.
Needless to say, we’ll touch on everything that you need to know about it, starting right from the basics. Let’s get started then, shall we?
What Is Backflow?
The water flow in your home or business property is unidirectional, which means it flows in one direction only. Clean supply enters from one side and leaves through the other, and this movement is carried out by maintaining a uniform pressure.
If for some reason, the pipeline experiences pressure fluctuations, the used water might get mixed up with the clean one. This flowing back and the mixing phenomenon are known as backflow.
Think of all that grimy water that gets drained from washing machines and dishwashers that goes down your sinks and basins. What if it got mixed with the clean water supply?
It’s too gross even to imagine, right? This can give rise to severe gastrointestinal diseases too, that’s why backflow testing is a must.
Now, backflow can occur because of two reasons: backpressure and back-siphonage. Backpressure flow is when the pressure in the plumbing suddenly increases because the downstream pressure is higher than the pressure at the source.
At the same time, back-siphonage takes place when the direction of the water flow changes because of pressure fluctuation. This can occur when a fire hydrant is hit by a vehicle or when a garden hose draws filthy water from the backyard into the potable water storage.
What Is Backflow Testing?
Backflow testing is a quick and straightforward method to evaluate whether clean water is mixing with filthy water, as we discussed above. In this test, a plumber assesses the functioning of the backflow preventer installed in your pipes and plumbing system.
The test is mainly conducted with two purposes: first is to check whether there’s a backflow in the supply line, and second, to pinpoint the reason behind it.
Why Is It Important?
To be confident about thequality of water that you are consuming, it is crucial to get the supply system tested annually. It is an integral part of home maintenance because it gives a conclusive report about whether the water at your home is clean and safe.
A few advantages of backflow testing are:
1. Protection Against The Presence Of Heavy Metals
Heavy metals can enter your water supply, especially if you are a business owner or own cafes and restaurants. A typical example is the contamination of clean water by copper because of soda dispensers.
The carbonated solution in the dispensers can corrode its inner surface, carrying it to the pipes that transport used water. If backflow happens in this situation, it will definitely lead to copper poisoning in the individual who consumes it.
Similarly, other heavy metals like chromium, lead, and arsenic employed in metal plating can also seep into drinking water.
2. Preventing Waterborne Diseases
Disease outbreaks like typhoid, diarrhoea, and dysentery occur because of faecal infiltration into drinking water. There’s a very high chance of such infections when the backflow of water takes place. In fact, the majority of gastrointestinal infections are caused by coliform bacteria like E. coli and Salmonella that thrive in dirty water.
3. Prevention Of Chemical Contamination
Compounds like sodium hydroxide, herbicides, and insecticides can enter the water supply through backflow and be a threat to your health. Noxious chemicals like these can also cause liver, breast, pancreatic cancer, and leukemia.
The Process Of Backflow Testing
There are certain technicalities that must be taken care of before carrying out the test, and the licensed plumbers that you hire should look after them. Firstly, you’ll need to take permission from the representative or owner of the property to shut the water supply.
For the sake of convenience, kindly inform everybody about the water cut off before the test so that they can plan accordingly. Next, inspect the area thoroughly, observing the assembly of the device and its surrounding area, and note it down if possible.
Also, verify the producer of the system and record its location, serial number, model, and size. Once all this is done, you can proceed with the testing.
Backwater testing involves the use of relief valves and gates on the testing device by shutting off the valves and noting fluctuations in the gauge movement. These changes can point to leakage or other plumbing issues.
The important criteria that must be met in the test are:
- Ensuring the regular opening of the airports
- Ensuring the check gates stop the backflow
- Making sure the timely opening of relief valves
The last step should occur before the pressure difference between the inlet device and check valves go below two pascals.
How To Prevent Backflow?
This gruesome phenomenon can be prevented by installing devices and assemblies that stop the water reversal in the system.
However, once the backflow prevention devices are installed, it isn’t possible to test them as they do not have test valves or outlet and inlet valve shutoffs. On the other hand, backflow prevention assemblies possess all the necessary shutoffs and valves that can be regularly tested for effective and safe functioning.
So, let us discuss the different types in detail.
1. Atmospheric Vacuum Breakers (Prevention Device)
An atmospheric vacuum breaker, commonly referred to as an atmospheric siphon, requires air pressure for functioning instead of water pressure. Its inlet valve remains closed when the water flow is proper but opens when it reverses and prevents back-siphonage.
These assemblies are effective in central systems but aren’t economically feasible in complex plumbing since they need to be installed after every zone, pipe, or control valve.
2. Pressure Vacuum Breakers (Prevention Assembly)
This simple assembly is the most effective and commonly used for backflow prevention. It’s available at an affordable price and is economical to install, repair, and maintain.
The basic structure is composed of a valve body having a pressure vacuum breaker and an inlet shutoff valve. It also has check valves loaded with springs, designed to shut down as soon as the water stops flowing.
But the drawback is that they are made for stopping back-siphonage only.
3. Spill-Resistant Vacuum Breakers (Prevention Assembly)
These installations are leak-proof and do not allow water to spill, proving effective barriers for back-siphonage. They are similar to pressure vacuum breakers but have an additional diaphragm to prevent spillage from the air inlet under high-pressure conditions.
4. Double Check Valves (Prevention Assembly)
The double check valve assembly (DCVA) is the perfect backflow preventer for in-line or underground usage. Ideal for both outdoor and indoor pipelines, it consists of a valve body, an inlet shutoff valve, and two check valves that operate independently.
Along with that are a shutoff valve for the outlet, and four test valves.
Now, unlike SVBs and PVBs, DCVA can safeguard the plumbing against both backpressure and back-siphonage. Hence, we can say they are excellent backflow preventers.
Why Backflow Testing Is A Must!
Backflow of water can be dangerous for you and your family’s health, and that is why regular testing of the plumbing system is very important. In other words, this is something that cannot be overlooked or neglected.
We have now reached the end of our comprehensive guide on everything related to backflow. The guide covered its type, the testing process and prevention devices; hopefully, you got to know all that you wanted.
But before signing off, we’d like to brush up on a few things. Backflow testing is done to check the occurrence of backflow and to find its root cause. The procedure requires the area’s water supply to be shut off for a while, so you should inform the residents before the test.
That’s pretty much it. We’ll see you next time, take care!