Introduction: A Survival Water Filter

In the world we live in, you never know what is coming next. Fires, hurricanes, and other natural disasters can lead to apocalypse-like situations. That is why you should always be prepared to be able to survive in many conditions. One key factor to survival in all situations, is getting clean water for drinking. In this Instructable I will show you how to build a filter for water purification, using only materials found in the wilderness (from scratch), with the exception of cloth. I will also show you where to get water in the wilderness and how to finally boil your water for purification in the wilderness.

So let's get started!

Step 1: Gather Your Materials

For this Instructable you will only need to use one tool - A knife

Here is the list of the materials we will be using:

-Birch Bark

-A Small Live Branch or Small Live Plant




-An Article of Clothing (Preferably a Bandana)

The first thing we are going to need for the filter is the birch bark. We will use this bark to hold the filter together in a cone shape. In order to shape this bark correctly, you have to cut the bark in a half circle with a diameter of roughly one foot. Using this shape you can roll the bark into a cone. Of course, this is the natural materials only version of this filter. Instead of using Bark to make the filter shape you could use the top of a water bottle that is cut in half

The second item is a small live branch. Normally I wouldn't cut live branch, because I don't want to harm living things, but this is a survival situation. We need to use the live branch to tie the cone shape together. Use branch or plant that is roughly a foot long and as thin as paracord.

The third, and most important item, is the charcoal. Make sure the charcoal that you use is bought from the store, otherwise you could get ash in your water and it could be poisonous.

The next materials include stones and gravel. If you are in an area that does not have sand, then do not waste your time looking for it because it is not the most important part of the filter. You only need about a handful off each of these materials.

The last material is a type of cloth. Although it is not found in the wild, cloth may be the easiest item to retrieve on this list, considering that most people wear clothing. A bandana works best for this part of the filter. If you do not have a bandana

Step 2: Build the Filter

This filter is actually very simple and easy to build. The difficult part is boiling the water you filter.

The first thing that you should do is roll the bark into a cone and use your knife to poke a hole through the overlapping part.(image 1)

String the leaf or branch that you picked earlier through the hole and tie off the end using a square knot. If you do not know how to tie a square knot, use the directions from my other instructable on how to do so.(image 2)

Now, take your pieces of charcoal and put them in the center of the piece of cloth you have(image 3). Now bring all the corners of the cloth together so the charcoal sits in the bottom(image 4). Now, covering the charcoal, use your hand to smash it into a powder(image 5). Put the part with charcoal into the cone and spread out the corners so you can see the charcoal(image 6).

Pile on the gravel and then the rocks and your filter is set to go.(images 7&8)

Step 3: Find Water

I will show five good ways to find water in the wild:

  1. Standing Water
  2. Running Water
  3. Using a Solar Still
  4. Plant Perspiration
  5. Cutting vines

1. Lakes, and Ponds (image 1). Standing water is very easy to extract water from. All you have to do is scoop up the water, pour it through a filter, and boil it. Try to use larger sources of standing water because then there is a lower sediment to water ratio. Always scoop the water from the top surface of the water.

2. Rivers, Creeks, and Streams (image 2). Running water is very easy to extract water from because it is moving and you can fill up a container without any effort. The only problem with running water is that it can be in a very small stream and hard to fill a container with. Remember to filter and boil this water.

3. Using A Solar Still (images 3-5). A solar still is a very neat way to get water that you can build pretty easily. The only problem is that you need a couple of items that don’t belong in nature. They include a plastic sheet (preferably clear) and a container for water (I use a cup). A solar still is basically a tiny well with some vegetation inside it. The well is covered with a plastic sheet which all the moisture is brought up to. In the center of the sheet is some type of weight which the water runs down off into the cup.

The first step is to dig a hole in an area that gets a lot of sun (image 3). Then find some small plants that are alive and very green. Rip these plants out of the ground and scatter them throughout the hole. Now take your container and place it in the center of the hole (image 4). Take the plastic sheet and stretch it over the hole. Using sticks or big rocks, stake the sheet down. Finally put either a log or a rock in the center of the plastic sheet and wait for a few hours (image 5). The water from a solar still doesn’t need to be filtered but it does need to be boiled.

4.Plant Perspiration (images 6-8). Plant perspiration isn’t the real name of this method, thats just what I call it. This method, like the solar still, also uses one item that can’t be found in nature, a plastic bag. All you need to do is put the bag over a branch of the plant. The plant will release moisture and it will get trapped in the bag. This method works well but you need to wait several hours until you have enough water. You do not need to filter this water but you do need to boil it.

5. Cutting Vines (images 9&10). This is the most unreliable method of them all, but it does work under certain conditions. The only problem with this method is that large live vines are hard to find and sometimes they are not alive. You also need patience because it takes a while for the water to drip out of the vine.

Step 4: Boil the Water for Purification

Boiling water in the wild is no easy task and It can be very frustrating. I will show you one way to boil water will only natural items and I will give you suggestions on other ways of doing it.

The way I will show you is boiling water in a hole in the ground. You will need to be in an area where clay is under the soil. We will use the clay to line the hole in the ground so that no water leaks into the earth. This is pretty simple, dig two holes, one for boiling and one to get clay. Take the clay and add a little bit of water to it so you can apply it to the hole. Seal off all the dirt. Now you can pour water into it and get your fire going along side it. You will need to find dry rocks to do this (wet ones will explode). Put a few rocks in the fire and once they have been in the fire for a while, you can put them into your water using another two sticks as tongs. You know its boiling when its bubbling.

other ways to boil include:

-In metal cookware over a fire

-In a water bottle in the fire

-In a live leaf over the fire

-In a wooden bowl you whitled

Step 5: The End

Now you know how to put together a water filter in the wild. The gray tint in the cleaned water is due to the charcoal, but as long as you boil the water it should be o.k. to drink.

This method for water purification is for SURVIVAL CONDITIONS ONLY, and it is not the best method of purifying water if you are near civilization. I am not responsible for any injuries or medical incidents related to this instructable.

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