How Does Water Tank Chlorination Work?

Water Tank Chlorination is not something you should put off doing. Water that sits in a holding tank may not be safe, regardless of the source of the water. Your water tank should be cleaned regularly, preferably by a domestic tank cleaning service, but it’s also important to chlorinate the tank as well.

Not sure what might be lurking in your water tank? You can have microbiological testing done to see. It can be frightening to see what is in your drinking water, but with ongoing testing, you’ll find it is easy to maintain the water tank and prevent future contaminations from getting out of control.

What is Water Tank chlorination?

Water Tank Chlorination is when you add chlorine to water in order to kill off any unpleasant microorganisms in the water. It works by weakening the microorganism’s cell membranes and then the chlorine makes its way into the cell and interrupts both cell respiration and any DNA activity, effectively killing the bacteria.

Some areas chlorinate their water as a matter of course and the chlorine is then ingested by the people relying on that water source. This can cause the water to have an unpleasant taste and smell, but it does eliminate the possibility of microorganisms.

However, if you have a domestic water tank, you can simply flash it with chlorine and let that sit for a little while before you continue to monitor everything and flush out the chemicals. Your water will return to its normal state, but without contamination. It’s important to test your water regularly so you can be sure to avoid drinking anything that may be contaminated with legionella or another bacteria that could prove harmful. You should start out testing weekly, but then you can begin to do it less frequently when the system is balanced.

Domestic Water Tank Chlorination

You may be able to do this on your own, but for most people, it is so much work and the fact that the tank must be completely disinfected and properly chlorinated means they’d rather leave it to a professional. Proper water hygiene is very important, even if you have a water filtration system.

Chlorinating a domestic tank involves shocking the tank with chlorine to kill anything in it. You then ensure that the chlorine makes it through the system to every pipe and outlet so it will be certain to kill anything that may be in the system. Once the chlorine is flushed out of the entire system again, your water should be completely safe. This process is one that must be carried out precisely and involves measuring the amount of chlorine in the tank and in the water that comes out of the faucets. You will need the ability to measure the chemical.

It’s also important that the cleaning process is done properly and completely. If there is any contamination left in the tank before chlorination, the chance that someone might eventually get ill is much higher.

Here’s how to clean and chlorinate your water tank.

Cleaning the Water Tank

This process eliminates any scale or build-up that may occur in the tank after months of water coming and going. There may be sediment in the tank, as well as chemical deposits left by the water itself. The cleaning doesn’t necessarily make the tank safe to drink from, it simply eliminates the visible grime.

1.  Isolate any electrical systems, including pumps.
2. Reduce the temperature of any hot water that will be disinfected to under 24ºC.
3. Close both the inlet and outlet valves.
4. Drain the tank to half and then open the inlet valve to flush the rising main. Do this for five minutes to flush any sediment into the tank so the main will be clear later.
5. Completely drain the tank.
6. Scrub the interior of the tank with a 10% bleach solution and remove all stains and scale that has developed.
7. Remove any sediment.

Water Tank Chlorination

This process will kill off any bacteria or microbes that may be thriving in the water tank or the outlets. As long as the water coming into the tank is safe, the chlorine should take care of anything that lingers in the tank or in the water pipes. Here’s a step-by-step guide.

1. Add enough chlorine to reach 65ppm once the tank is full.
2. Refill the tank.
3. Test the water to ensure the chlorine level is at least 65ppm. If it’s not, you should make adjustments by adding more chlorine.
4. Open the outlet valve again.
5. Re-activate the water pumps.
6. Open the outlet or faucet furthest from the tank and let the water run until a chlorine test strip confirms water has reached the outlet.
7. Repeat Step 6 with all faucets, moving back toward the tank.
8. Add more chlorine to the tank to bring it back up to the correct levels.
9. Test each outlet for the next 15 minutes to ensure the chlorine continues to remain I the system.
10. Neutralise free chlorine in the tank. Use a pump to mix if needed.
11. Cut off the electricity to the pump and anything else in the tank and drain the tank.
12. Refill the tank with cold water.
13. Re-activate the pump.
14. Flush water through the outlets again until the chlorine level in the outgoing water is the same as the chlorine in the mains water.

At this point, your chlorination of the tank is complete and all the pipes in the system have been chemically shocked and cleaned. It’s a long and drawn-out process but will ensure that the water you drink is clean and uncontaminated.

Water Tank Chlorination – Why do it?

While you now know exactly how domestic tank cleaning works, why would you need to do this? The water in the UK is safe, but when water sits for a period of time in a tank, it can develop bacterial growth.

Perhaps the biggest concern for sitting water is legionella. Legionella tends to thrive in water that is over 20ºC or under 50ºC, so if your tank has water in this range, it could be developing dangerous contamination. The same thing happens in dead legs or pipes that no longer lead to a used outlet. If your water system fits either of these criteria, you should consider microbiological sampling.

Legionella bacteria can cause you to become ill when you inhale droplets of the water, such as in the shower or when you drink it, as drops can end up in the lungs. This bacteria can cause Legionnaire’s disease, which can be extremely dangerous if left untreated. If you notice that you have symptoms like muscle aches, fever, cough, and chills, you should evaluate your water and have microbiological testing done to ensure your water isn’t the problem.

Water hygiene is extremely important if you want to be sure that no one will become ill from drinking or being around your water. While a water filtration system is very helpful, you still need to ensure you drain and chlorinate the tank on a regular basis. If all this sounds like far too much work to deal with on your own every few months, don’t worry. It really is a lot for the average person, which is why most people simply hire a domestic tank cleaning service to handle all the cleaning for them.

A Water Tank Chlorination service will evaluate your water tank, and perform all of the above steps to ensure your water is not only clean but also perfectly safe for any type of use. Now you just need to schedule them to come regularly so you can be sure your water stays safe.

You should also consider regular microbiological sampling to check for anything else in your tank. Water can hold many bacteria and may be contaminated long before you suspect anything or even before anyone gets ill. If you are testing, you can treat the water immediately and prevent illness. Fresh, clean water is a blessing that not everyone receives. If you have that accessible to you, be sure to avoid losing it and getting ill.

How we can help

Are you looking for a reliable company to handle your tank cleaning and disinfection? Look no further than H2O Comply. We make the process of cleaning and chlorination much simpler for you and handle all the hard work ourselves. Contact us today to schedule your appointment.