How To Build An Emergency Water Filter

Water is the most abundant resource on this planet. Science has shown that 75% of the planet we call home is covered in water. However, the sad reality is that of this available water, a great majority is salt water. Now every survival expert will remind you that drinking saltwater is a death sentence.

If you are in a survival situation, there is nothing more important in terms of supplies, than making sure that you have drinkable water. There are a few things that you need to keep in mind. First, it is always important to be prepared. An ounce of prevention is worth a pound of cure. To put it simply, why not stock up on an essential need? It is recommended that you store ½ a gallon of water, per person, per day for drinking purposes. If you have four members in your family, you should keep a supply of 28 gallons of water or enough for 2 weeks.

Second, it is very important that you understand the difference between purifying water and filtering water. When your water is filtered it means that you are removing obvious debris and some harmful organisms. However, filtering is not an alternative to purification. When water is purified it is completely devoid of harmful bacteria, viruses, and microorganisms.

If however you find yourself in a situation where you need to find drinking water, and you are not sure of the safety of the water, it is possible to build your own filter. How is this accomplished? It is relatively easy but it will require a bit of time and dedication. Here is a step-by-step guide to building your own basic charcoal water filter.

1. Get Charcoal


Charcoal is the main ingredient in this filter. There are many different kinds of charcoal that you could use. However it is very important that you use a charcoal that does not contain any harmful chemicals. If you are using briquettes, make sure that they are natural and that they do not contain any starting fluid.

If you do not have access to clean charcoal then you are going to need to make your own. You will need to build a fire and burn your own wood. Be sure that you are not using starter logs because they have been treated with starting fluid. Once the logs begin to char, or turn black, it is time to remove the logs. Do not allow the logs to turn white or grey with ash.

2. Prepare The Charcoal

At this point you will need to take the burnt logs and turn them into usable charcoal. In this step you will need to use a hammer and maybe a towel. Use the towel to cover the wood and then hit the wood with the hammer. The point here is to make sure that you pulverize the charcoal on the wood. At this point it is very important that you completely pulverize the charcoal. Leaving any large clumps will keep your filter from working as efficiently as it could.

You will have enough charcoal for the filter when you are able to fill your container 1/3 of the way with the powdered charcoal.

3. Prepare The Container

The container you use could be a variety of items. The important thing to remember is that you need to have enough room to store your charcoal and to pour water into it. You could use a soda bottle that has had the top removed.

Once you have secured a container you will need to perforate the bottom of the container. This can be done with a pocketknife. The end product should resemble a showerhead or a small colander.

4. Layering Your Filter


Your container is going to have five layers. The first layer needs to be coffee filters, cheesecloth, or even grass. If you choose or use grass make sure that it is free of any chemicals or fecal matter. The first layer will serve to keep the charcoal from running through the container. This layer will be approximately 1/6th the total height of your container.

The next layer will be sand or soil. Again, make sure that the soil or sand is free of debris and chemicals. Pack the layer and move to the next layer. This layer will be 1/6th the overall height of the container.

The third layer will be charcoal. This layer will be 1/3rd the height of the container and it will serve as the heart of the filter. While the previous layers will only remove large debris, the charcoal can remove many smaller organisms and bacteria. It will not be perfect but it will cut down on much of the possible pollutants.

The fourth layer will be more sand or soil. Do not pack this layer. The fifth and final layer will be more coffee filters or cheesecloth. Again, grass can be used if you do not have coffee filters.

5. Collect Your Water

Collecting your water is very important. It is important to use common sense in this area. Do not choose murky water if at all possible. Opt for water that is flowing instead of standing. Try to avoid water that might have come from a contaminated area, such as a livestock pasture. Rainwater is best but it is not always available. Water from higher sources is better than water from lower areas.

6. Filter Your Water

At this point you will need to use a second container to collect the filtered water. With your filter above the second container, slowly begin to pour water into your filtration device. Do this very slowly. As the water begins to flow through the filter it will enter the second container a bit murky or cloudy. This is normal. This water should be discarded.

Eventually the filter will begin to deliver clear drinking water. In an emergency situation this water will be drinkable. Keep in mind that this filter will not remove viruses or small bacteria. However it will offer a better option than simply drinking water straight from a sketchy source.

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About Ms. Prepper

I’m Laura P, aka, Passion Prepper, aka, Storage Prepper! I’ve been homesteading nearly all my life and prepping for the last 6 years. I strongly believe our great country of America was built on self-sufficient families like mine and yours. Politics bores me, learning new stuff, getting outside and living life thrills me.

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