Water is usually always the first priority in an emergency survival situation. Without it, we cannot survive for very long. The average person needs to consume at least 2.2 L to maintain normal body function. That amount will vary depending on a person’s mass, metabolism, and exertion. When a person fails to replenish lost fluids, he quickly becomes dehydrated.
You will almost always need some basic conventional tools when attempting to purify water. Just because a water source is clear does not mean it is clean. The only water we can count on to be pure, in the wild, is that which we either purify and distill or collect through rainwater or condensation.
In arid environments, it is possible to collect some condensate in the morning time through the use of a sheet of plastic. Surface area is your greatest ally. The larger the sheet of plastic, the more condensate you will collect. Stretch out the sheet of plastic. Place a rock or heavy object in the middle and then stretch the ends of the plastic sheet out so they form a 30-45° angle.
This will let any water accumulated run to the center.
Collect the water in the early morning just after the sun has come up. If left exposed to the sun, a lot will be lost due to evaporation.
This is not usually a sustainable practice in an arid environment and the ambient temperature must be greater than freezing for this to work.
In a similar fashion, you can use the same strategy to collect rainwater. Rain is clean, potable water. The more tarps you have, the more opportunities you have to collect the water. If you have plastic bottles, you can store that water in them until you need it. Rainwater is liquid gold in the wild.
Both of these will ultimately supplement your water supply. They will likely not meet your daily requirements. For that, you will need a water source and at least some equipment or tools.
Making A Water Filter Out Of A Plastic Bottle
If you don’t have charcoal handy, you’re going to need to start a fire. The part of the fire you need is the unburned embers that have cooled off. Hardwood coals are the best. This will be later used in your filter and cannot be overlooked.
- Poke several holes in the cap of the bottle. Be careful not to fracture or damage the cap. It needs to have pores for water to flow through.
- With the plastic bottle in hand, turn it upside down so the bottom of the bottle is facing up.
- Cut off the bottom of the bottle.
- You will also need to use a piece of cloth. You can cut it from a t-shirt. The cloth needs to line the bottom of the filter.
- Put a mixture of fine stones into the bottle so they are resting on top of the cloth.
- Add crushed charcoal you procured from your fire. This should constitute the biggest proportion in your bottle filter.
- Add a layer of sand and fine gravel on top.
- If you have any tissue material, add this to the top as it will act as a pre-filter.
Ideally, this filter should only be filled no more than 2/3 of the way with filter materials. You will need that remaining 1/3 space to load water.
The filtration will take much longer than anyone would like. It will continually need to be topped off. The filtered water product is not technically potable (ready to drink) at this stage. It would probably need to be boiled before it would be considered safe to drink.