# Survival > General Survival Discussion >  Can you boil water with a campfire?

## tunick001

I was just wondering, I've never tried it before. Lets say you're lost in the forest and need to boil water for drinking. You have no stove or fuel to do it. You start a fire with a bow-drill. Will that work?

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## Rick

Sure it will. You can boil water with any fire as long as it will burn long enough to bring the water up to temperature. You need something to boil the water in, of course. You can use a metal cup, a foil cup, a plastic bottle, or heat rocks to place in just about any type of container that will hold the water.

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## Alpine_Sapper

http://www.expertvillage.com/video/5...ling-water.htm

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## vagrant

What I do is build fire with lots of finger width kindling to build up a quick hot fire. I like the rock method by placing several equally high rocks in the center that my pot can sit on. Make sure you don't use wet rocks or those by creek beds because these can and do explode from moisture content. When I camp I keep a large supply of kindling by the fire ring or pit and in the morning get the fire going with alot of small fuel, placing the rocks in the center. Usually within a half hour I have a fire hot enough to boil water rather quickly. Within an hour I have a pot of coffee made over a hot fire instead of wasting my propane or camp stove fuel. 
If you need to boil water for survival purposes and don't have anything to boil in, use rocks with depressions in it or use aluminum foil for the holder(I have some folded in my emergency kit) making sure you don't have it directly over the fire so it doesn't scorch or burn thru. You can also place hot rocks in your water jug but I never tried this and am not sure if the water gets hot enough to purify it. Hope this helps  :Smile:

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## Alpine_Sapper

> You can also place hot rocks in your water jug


I wonder if the rock would explode if hot enough...Anyone wanna test it?

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## Rick

If water boils it will be purified.

Only if the rock has moisture content in it. Once you drop the rock in the fire and heat it up, it's already reached temperature so dropping it in the water carrier (whatever you use) won't cause it to go pow. It could crack from a sudden change in temperature but a moisture laden rock explodes because the steam can't escape quick enough. 

And no thanks. I don't want to test it.

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## Tahyo

> If water boils it will be purified.
> 
> Only if the rock has moisture content in it. Once you drop the rock in the fire and heat it up, it's already reached temperature so dropping it in the water carrier (whatever you use) won't cause it to go pow. It could crack from a sudden change in temperature but a moisture laden rock explodes because the steam can't escape quick enough. 
> 
> And no thanks. I don't want to test it.


I've had some rocks go POW back in my younger days and it's like a bomb going off.  Take my word for it, when you get the right one that goes off, it will literally blow your campfire all over the place.

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## vagrant

@rick: Like i said i haven't tried it but by just placing hot rocks in your water, is that enough to make it safe to drink? I have read it somewhere before but my thoughts were always that if water didn't boil for 5-10 minutes it wasn't safe enough.

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## Tahyo

As soon as water comes to a rolling boil, it's safe.
add) I don't know about dropping hot rocks in it.  I'd pass on that for drinking.

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## Rick

Robert Rogers, another forum member, does some write ups for a wilderness web site. he did some timed studies on water temperature. He says the same thing. When the water comes to a boil, it's safe. 

As for the hot rocks. I'd wipe them off before I dropped them in the fire but you just heated them to beyond 212F (100C) so they are clean. Once you dropped them in and the water boiled, I'd drink it.

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## Rick

You can use just about anything to heat water over a fire. Even a plastic bottle or paper cup. You have to fill it completely full for it to work. The reason it works is because the water acts as a heat sink and pulls the heat away from the container. If you leave any air in the plastic bottle, the air will transfer the heat to the bottle and it will melt. 

Here's a very short video of rocks boiling water. 

http://www.youtube.com/watch?v=BfIQqnBMwuE

This has been posted on here before but I thought it might be a good time to review: 

http://www.youtube.com/watch?v=WuMl2...eature=related

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## Sourdough

Do you ever ask, Why do I live where the water is not pure directly from the creek or lake.....?????

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## Tahyo

I use to make an annual trek down to Ark. where a couple of guys I went to school with would get together on a 2 week long camping trip on the Little Missouri river.  We use to take one of those 5 gallon plastic pails and fill with river water, set in the fire every morning and heat it up for water to wash off with.  We had the same bucket for about 5 years and other than a few places where the plastic stuck out and sort of melted, none of the main part of the bucket was hurt.  The first time we did it, we all stood around it thinking it was the coolest thing.

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## vagrant

Thanks Rick I never saw the bottle trick either  :Smile:

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## Rick

Never did Hopeak. Mostly because I was getting old before I knew there was actually clean water some where on the planet.

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## Alpine_Sapper

> Never did Hopeak. Mostly because I was getting old before I knew there was actually clean water some where on the planet.


W - H - A - A - A - A - T - ? There's clean water? OMFGWTFBBQ!?!?!

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## bulrush

> If water boils it will be purified.


I must contest this, Rick. Water at higher elevations will not "boil" at 212F, the normal boiling point at sea level. But keeping the water at 212F, even at higher elevations, for 10 minutes is enough to purify it.

Oh wait, if you are at a higher elevation and it boils, the water has exceeded the 212F and is purified. Doh.

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## Rick

Well, contest away. See post #17 on this thread: 

http://www.wilderness-survival.net/f...0975#post30975

And note I wasn't talking about boiling water at 212F but heating the rocks to kill bacteria. I indicated that once the water boiled it was safe to drink. That's true regardless of elevation.

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## LiL' bunny fufu

if you have a bottle or can it should work fine otherwise im lost

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## Rick

Why are you lost?

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## Tony uk

> I must contest this, Rick. Water at higher elevations will not "boil" at 212F, the normal boiling point at sea level. But keeping the water at 212F, even at higher elevations, for 10 minutes is enough to purify it.
> 
> Oh wait, if you are at a higher elevation and it boils, the water has exceeded the 212F and is purified. Doh.


it does not need to "Boil" it justs needs to reach 100c to kill bacteria

And another thing i dont understand is the idea that you have to leave watter boiling for 5 or 10 minutes, After it reaches 100c everything is already dead, All they are doing it wasteing fule and water

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