Introduction: How to Purify Water in the Wild With 2 Water Bottles.

Picture of How to Purify Water in the Wild With 2 Water Bottles.

This is a entry to the "Keep the bottle" contest. Please take the time to vote if you think my instuctable is worth me getting a prize. I would really enjoy the prize, so please vote.

In this instructable, I will show you how to purify abit of water when you are in the wild and trying to survive with 2 water bottles.

Step 1: Things You Need

Picture of Things You Need

You need 2 water bottles. (If you find any in the wild)
Some duct tape or masking tape ( always carry some in any kind of outdoor trip)
Some dirty water or urine (really!)
Alot of sunlight

Step 2: Step 1

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First take 1 bottle and fill it up with dirty water. Make sure that it does not leak outside the opening of the bottle when on its side.

Step 3: Step 2

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Tape the other bottle to the opening of each other. Make sure that none of the contaminated water or liquid flows or leaks into the empty bottle.

Step 4: Step 3

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Place the taped bottles in a area where sunlight is always shinning. Place the 2 bottles at a leveled area where there no slopes or leveled ground. EDIT: Sometimes you want to place the clean bottle abit upward so the evaporation can collect more better. But just a little bit so the purified water doesn't drain back to the dirty bottle.

Step 5: Step 4

Wait for most of the water to evaporate into the other bottle. (This might take more then 12 hours)

Step 6: Enjoy!

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Carefully cut open or peel open the tape and drink the fresh water in the bottle that does not have the contaminated liquid.

Step 7: Wondering How This Works?

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Wondering how this works? Well....the contaminated water will go into evaporation because of the sun, the evaporated water will collect in the other bottle giving you fresh water.

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JohnS407 (author)2016-02-25

You may not know this, but you can simply filter the water if it is murky. Then place the plastic bottle in the sun after you take to label off. Place it on a rock for eight hours. The ultra violet light will kill most all bacteria. Water in a zip lock bag will work too.

CoachDan (author)JohnS4072016-09-02

Actually, only 6 hours of direct sunlight is required.

foxposte (author)2016-02-06

I just thought of a great addition to the survival kit: get a small plastic Freznel lens--they are now available very cheaply on-line--get the kind that spreads the light a bit rather than focusing it, and you can heat up your water, or cook food, especially if combined with aluminum foil for extra solar reflection. You do need some sunlight for this method to work. Be careful not to burn yourself!

RobertH79 (author)2015-09-12

With the flames of a fire to sterilize the bottles it can be done. People get the wrong idea to a certain point. When they see films of actors putting knifes in the fire to use for surgery etc. And its glowing hot.. its mostly cauterizing. To stop bleeding and kill bacteria. When running the blade through the fire can still kill bacteria. Same with the plastic bottle. But really you can't disinfect inside the bottle with the flames. It won't work.

RobertH79 (author)2015-09-12

great idea, but too risky to a you really have to be careful not to cross contaminate the clean water. One drop of contaminated water can cause the user alot of harm. As over 1000 bacteria can be transfered.

KenConstruct (author)2015-09-10

This should work - it's evaporation/condensation. Though I think you're better off digging a water pit and using a tarp, but this should work too. If you can somehow set the source water on a hot rock and get some stream water over the collection bottle, that would work even better.

jeff-o (author)2009-01-19

How do you clean the bottle that you drink from?

dkfa (author)jeff-o2009-01-19

usually people throw away bottles with the caps on. So the inside should be clean. But if you can only find a dirty bottle, then sterilize the bottle by using heat over a fire.

Clanky (author)dkfa2009-01-25

Heating a bottle over a fire will melt the bottle before the usual bacteria are roasted. Also, if you have a bottle that can resist enough heat to kill bacteria, why not just put water in there and boil it? Much faster than waiting for the sun to evaporate it.

Light_Lab (author)Clanky2010-02-06

Actually most bacteria are destroyed at lower temperatures than required to melt a PET bottle (270C) or even distort it (~80C) in fact they use thick PET milk bottles in Germany and heat sterilize them - same for some baby bottles. Even the UV in sunlight will kill some bacteria.

Nevertheless the point made elsewhere that if you have a source of heat to evaporate the water is a valid one, much quicker than the Sun. I think though that if you were dying of thirst you would risk a few of someones bacteria. (Probably safer than a kiss.) Or you could discard the first collection.

What worries me is why the water would selectively condense in the clean bottle. The primary bottle would always be cooler because of evaporation. I would cover the contaminated bottle with something black and cover the clean bottle with a wet cloth or wet soil (wet with contaminated water would do). In the wind this would evaporate and cool the clean bottle.

A tried and true trick is to cover a small container of dirty water standing in a bowl with a closed cylinder cut from a plastic bottle. Standing in the sun; the water condenses on the plastic and runs down into the bowl. This can be tuned with bits of damp cloth to be quite efficient.  Except for the bowl you can make this all from one 2 liter bottle.  Obviously several of these would be required to keep a person alive. 

zbuilder (author)Light_Lab2015-06-22

hmmm, why would the water vapor go to the clean bottle & not stay in the dirty bottle...hmmm... I've been thinking about this. Maybe because as liquid water turns into water vapor, latent heat energy is absorbed in the water vapor, cooling the surround air (including the air in the clean bottle). Since most of the heat energy is now in the vapor, the clean bottle is now probably a little cooler and enough to start a natural air circulation cycle of hot area to cold area. The water vapor now condenses on the slightly cooler, clean bottle. From a weather science article, "When water changes to a phase with less energy, such as vapor condensing into water drops, the water gives off the extra energy - called latent heat - to it's surroundings. When water changes into a phase with more energy, such as raindrops evaporating into water vapor, it draws heat from it's surroundings and cools." A perfect example is the cooling effect of perspiration, because liquid water turning into water vapor carries heat energy with it and we feel cooler.

the water condenses in both it just evens out, and you can slightly tilt the bottle to collect more evaporation

jeff-o (author)theRIAA2009-05-08

Cooooool! I shall remember that trick, and will amaze my friends with it the next time we go camping.

dkfa (author)Clanky2009-01-25

Well, most people don't think the trip will turn into a mess. So people don't usealy bring a flint or even have one for starting a fire. How many people do you know that know how to start a fire with just wood, a shoelace, and a rock? Not much. Im just saying that many people don't know how to start fires or have a flint. So this would work well too.

bowhunterhall (author)dkfa2009-02-22

i know how to start fires and i have a flint...

Clanky (author)dkfa2009-01-25

Well, seeing as I am in a Scouting group... I was just commenting on your previous comment about using a fire to sterilize the bottle. Since a person is using fire to sterilize the bottle, I just assumed he or she had fire to boil water with.

bantoun (author)2013-10-19

But won't the sun rays hitting the receiving plastic bottle infect it from the the plastic itself? You should've thought about that before posting genius!

BigChowdah (author)bantoun2014-06-04

Actually the sun won't "Infect" anything there Hambone. Over time (A long time) it will breakdown the integrity of the bottle, but that is of little concern when you are trying to survive. The only misstep in this Instructable is reminding all involved to properly disinfect the area wear tainted water came in contact with the mouthpiece or screwtop of the potable water. As microbes can linger and be consumed from simple contact. Great instructable. Thanks for the tip.

rmconnelly5 (author)bantoun2014-01-01

That was really rude you saw that he was just a kid...

mugshotremoval (author)2014-06-01

Awesome way to distill water in the wild I hope I never get stuck in a bind and need to do this.

polypeo (author)2013-05-20

what about ammonia? it just evaporates and dissolves in purified water? Is is safe?

Schmidty16 (author)2012-08-08

um wont the plastic from the bottle make the water toxic

racopa (author)2010-08-05

Hello A simple variant would paste the two plugs for the outside and then make a hole. Greetings from Spain

maxman (author)2010-06-29

I really like this instructable. Short, and to the point. It's one of those things I'll file away in the back of my mind for some day.

Loserima (author)2010-05-16

this design could be improved upon if you found a tube to connect the bottles or if you were mtn biking/ backpacking use the camelback tube and go strait to the bladder. also mirrors/foil/metal/cut open pop cans (you get the picture) could help direct sunlight at the bottle.  

crajakum (author)2010-03-12

Put some foil in an arch under the dirty water bottle to focus the sun's rays.  This'll help the evaporation rate.

mikaelthemycologist (author)2009-05-23

I would put a handkerchief or something so that the clean water bottle is in the shade. This will help prevent re-evaporation.

mikaelthemycologist (author)2009-05-21

I LOVE YOU!!!!! Ive been trying to figure out how to make a simple still in the wild without the plastic sheeting that everyone says to use or without the use of a T-shirt or sweater!!!!!! YES!!!! VICTORY!!!! I Wish that I could still vote for you (its to late) YES!!!!!!!

andy221 (author)2009-02-02


good one

3232123 (author)2009-02-02

i tried it ..and it worked!!!XD

A good name (author)2009-01-31

I liked it. 4 stars cause it was a bit short.

trike road poet (author)2009-01-29

lay a rag or something over the empty bottle and the lower temp. will increase the condensing action and shorten the time of distillation.

ikenovak (author)2009-01-25

yea idk if the water would condensate on the "clean" water bottle or very much at all. Its possible that some of the water would travel to the other bottle but traditionally distillation works because it evaporates upward and through some sort of tube to a cooling element where it collects. Your method doesnt provide any cooling for the water to convert to liquid form and there is no logical reason for the evaporated water to prefer the other bottle. good try but needs some refining

Browncoat (author)2009-01-23

Wow, rude much? Did you not notice "We have a 'be nice' comment policy"? Anyway, yes, gas rises, but you show both bottles being level, so how does gas rising help it collect into the clean bottle? If anything, I'd think it'd be more likely to condense in the dirty bottle because there are already so many water molecules for the gas molecules to attach themselves to...

dkfa (author)Browncoat2009-01-23

Well, evaporation happens. And the condensation will not just go up and down up and down up and down up and down up and down. It will move about and collect in the other bottle.

Browncoat (author)2009-01-22

Why would it collect in the other bottle instead of just in the original bottle?

fun bun (author)2009-01-21

good one. =)

iddqd221 (author)2009-01-21

wow! This is a great way for surviving! Great instuctable!!!

bruc33ef (author)2009-01-20

Good job! This is the well-known "solar still" method, but using PET bottles is a useful idea when plastic bags or sheeting isn't available. And, if you don't have a source of even dirty water, you could stuff leaves and other vegetation in a bottle, screw the cap on, leave the bottle out in the sun upside-down, and the moisture from the leaves will evaporate and condense into water at the neck of the bottle. Then just unscrew the cap and drink.

dkfa (author)bruc33ef2009-01-20

You could also use moist soil if you dig under ground on a dry river bed or somewhere shaded.

dkfa (author)bruc33ef2009-01-20

But first, people need to know about the plants first. If they find some kind of poisonous plant and luckily don't get affected in any way, then the plant's moisture will be poisonous too. And they drink that, then they would probably get some kind of head ache or stomach ache( or die ). "When you can't move you can't survive." Good tip though.

PKM (author)2009-01-20

As this works much better when the clean bottle is cold, I would leave the bottle with the dirty water in the sun but bury the clean end bottle under a small mound of soil or something to keep it cool. This is pretty much the simplest take on the solar still I've seen, good work.

21GeeOff21 (author)2009-01-19

you could also run your dirty water through some sort of cloth and into your bottle aand if you can get a fire going you can actually boil the water in the bottle as long as the flames only barely touch where the water is but if you cant get yourself a fire i suppose this would work

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More by dkfa:Paintball, How it's done. Beginners GuideHow to purify water in the wild with 2 water bottles.Poor man's ipod speakers.
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