During an emergency, you will be able to live without food for several days, but without water, you can only survive for 2 to 3 days. It is common to get delusions if your body is severely dehydrated. You can purify water through a variety of methods like using a charcoal filter, treating it with chemicals, or boiling it. 

Although it is never advisable to keep on drinking from a contaminated source, in case of emergencies, you can use below steps to have a continuous source of clean water.

1. Always have a backup of clean water:
Emergencies never come forth telling. Therefore, you should always have a backup of clean water that you renew every day. I have kept two big plastic drums of water stored at my home, which I use on a daily basis, but I also make sure that those drums are filled up every day, and that their water is in rotation.

This is important because, in case of emergencies, you should have some clean water in hand before you start exploring new means of purifying water.

For this, keep two big plastic drums handy in the kitchen, or at a place where you can access them easily when required, and keep on using that water every day, and refill the drums every day or every two days. Also, ensure that you only use a big ladle or mug to take out water from those drums because you don't want the water to get contaminated from your hand.

2. You can clean tap water with a small amount of bleach as well:
Bleach can also be used to kill viruses and bacteria in water, but it is important to use only small amounts to avoid poisoning. Also ensure that bleach is not expired, or else it won't be that effective. To use it properly, you can follow the below steps to purify water;

• Fill a big container or jug with water - approximately 1.5 liters
• Add 4 drops of bleach per liter of water
• Mix the mixture by stirring it properly, and
• Then let the mixture sit for at least 30 minutes before drinking.

Again reminding that this method should only be used in case of emergencies, and not for cleaning regular drinking water.

3. Boil Water:
This is an old-age way of cleaning the water, and I believe this is one of the best ways to clean even the dirtiest water sources. Take water in a container, obviously, you should have filtered it first, then keep on boiling it. So, when I say boil, I mean when you see bubbles in the water, still keep on boiling it for at least 15 or 20 minutes.

Then leave the water to sit for some time, and then transfer the water to some clean utensils, keeping away the sediments that are settled at the bottom of the boiled water.

There is one more way of getting the purest water, but for this, you may require a few materials beforehand;

• Beaker
• Metal Lid
• Stand
• A small beaker

Now, keep a beaker filled with water on a burning flame, just ensure that it is tilted a bit, so that when you put the lid on that beaker, it should catch water vapors, and then those water vapors are transferred into the small beaker that is kept beside the original beaker.

This method will ensure that you have the purest form of water, and it will be helpful when you have only muddy or contaminated water. For normal tap water, you can just boil it and start using it.

4. Purify water with iodine:
Plain liquid iodine can also be used to kill pathogens in water, but many people are turned off by the taste. To clean the water, simply collect the water and add a 2% iodine solution. Stir in four drops of iodine per liter of water and let it sit for 30 minutes. Then use it for drinking.

5. Use a water filter:
Most water filters have become really good these days and several of them don't even require gas or electricity to run. Invest in one of such water filters beforehand and learn how to install them in case of emergencies. Usually, a commercial water filter is an easiest and most effective way to filter sediment, pathogens, metals, and other pollutants from water.

These filters usually have activated charcoals, carbon, ceramic, sand, and cloth that are specifically designed to filter out dangerous pollutants.

6. You can even use Pine Trees to remove pathogens:
Some plants have anti-bacterial properties and are effective in removing pathogens from water, and pine trees are one of those trees. To remove viruses and bacteria from your water, remove a small branch from a pine tree. Strip the bark from the stick and place the bare stick into a bucket. Slowly pour the water, letting it trickle onto the stick and into the bucket. As the water flows over the sap inside the stick, the sap will trap and collect pathogens in the water.

7. Keep water purification and disinfection tablets handy:
Water purification tablets are made of either chlorine dioxide or iodine and kill bacteria and viruses in water. To use these tablets, fill a pitcher or jar with water and add enough tablets to treat the water. One tablet usually treats 1 liter of water. These tablets generally need anywhere from 30 minutes to 4 hours to work.

One should keep in mind that these tablets do not treat water contaminated with protozoa or chemicals, and Iodine tablets are also not suitable for pregnant women or people with shellfish allergies.

8. Use the SODIS method:
SODIS is an acronym for solar water disinfection, and when done properly, it is a very effective method for killing pathogens in water. You can do this by filling a clear and smooth plastic bottle with water. Tighten the lid and place the bottle on its side in direct sunlight for 6 to 8 hours to kill parasites, bacteria, and viruses.

This method works because the plastic helps in trapping the heat from the sun inside the bottle, and the UVA rays pasteurize the water.

9. Use Sedimentation Method:
This method should always be used before boiling water if you have contaminated water. This can be done by keeping water in a jar or beaker for some time. Now you will be able to see that there are some particles that have settled down and some are suspended on the surface.

Remove the ones that are on the surface, and then again wait for the water to settle for some time, then slowly pour the water in a clean jar to ensure that the sediments that are settled below are not coming into the clean jar. After this is done, then one can boil the water and use it for drinking.

10. Make your own filter:
You can also make your own filter to remove large sediments from water. You will need some supplies, but you can use alternatives if necessary. Use filter paper or birch bark and curl it into a cone in place of the bottle and cap. Then use a shirt or towel in place of the coffee filter. Then, you can use nuts, roots, or grass in place of the filtration materials, and if you have charcoal, that is one of the great ways to clean water.

Conclusion;
Although you can source clean water in case of an emergency, several places in this world are still have contaminated water for drinking, and if you feel that several people are feeling sick because of the contaminated water, please use the above methods to clean your water.

A good society can only survive if you have health and education, and if you are reading this article, you are educated, and you can use that education to promote the health of your society.