Hi everybody. I have read many posts about water filters and there is one thing i cannot understand. Why buy a water filter when you can just boil the water ? What is the additional benefit of a water filter? Is there something that a distilation won't keep out? And while I am at it, does anyone knows how to make a water "distiller" that can be easily packed?
Thanks for the time

It is not always possible to boil water. Eg. run out of fuel, leak in the pot that you carry or your source has only muddy water, to name a few examples. Also, a filter is more convenient and quicker than boiling water.

I personally don't use a filter. the areas where i am ussually active have "clean" water, But I still carry purification tablets as a backup. Filters are just, too heavy to carry as just a backup in my situation.

If you need to treat all your drinking water, I suggest you get a filter. there are several that come highly recommended by their uses on this forum.

When hiking, filters are great because they allow you to "clean" a high volume of water quickly. I carry a tiny MSR titanium keetle that would take forever to boil 96 oz of water in. But it takes reltivley littel time at all to pump enough enough water through my filter to get that amount.

I imagine you would burn a lot of fuel if you used it primarily to clean water.

Let's start with why bother in the first place?

1) remove or neutralize biological pathogens

2) remove chemical and mineral impurities

3) Make it tast better

4) make fresh water from salt water


In general the options are.
a) boil the water - this doesn't mean distill it just get it hot enough to boil and then use it. This will kill all the bugs - or atleast any we realistically need to worry about including the plague.
b) poison the water This includes the chlorine, iodine and other chemical additives. The idea here is to add enough poison to kill the bugs without adding so much that we kill ourselves. A relatively safe approach since the bugs are vulnerable to a bunch of stuff that we aren't.
c) filter the water - This will remove the bugs if the filter is good enough. If a bug is small enough it will pass the filter but filters have become very small. most of the minerals and chemicals will also be removed by a good filter
d) distill the water - This requires making the water into steam and then condensing it out on a cooler surface and collecting the condensate.


Boiling the water doesn't take too much fuel and will take care of any reasonable bio contaminants but will do nothing about minerals and only a little about chemical impurities and won't drive off the salt of salt water only concentrate it a bit.

Poisoning the water will take care of the bio contaminants and do nothing about chemicals or minerals or salt

Filtering the water will take care of bio, chemical and mineral and if you get a very expensive filter you can make fresh water from salt. (Making fresh water is very hard and will consume a bunch of energy either from your muscles or a battery.)

Distilling water - This requires a bunch of input energy, usually some rather elaborate setup and a bunch of time as well but if you can do this in a precisly controlled thermal environment you will get 100% pure water with no contaminants even from salt water.

If you are packing for a psk the only thing that will fit is tablets.

If you are packing for a BOB the energy consuming options are poor because they also consume a bunch of time. So you have tablets or filters. Filters have no shelf life and address a wider range of issues. A good backpacking filter is small and light as well.

If you are in a longer term mode you might want to build a solar still so that you can be making water when the sun shines without haveing to work for it. This is not the typical survival solar still I refer to here - Those don't work. I am talking about using glass and plumbing to bring a ready source of water to a hot enough temperature to boil and then condense and collect. This presumes a good volume of questionable water readily available from a stream or pond.

If you are in a PSK or BOB situation and your first choice method doesn't work then be prepared to boil water in your cook pot for cleanliness. Won't address any industrial contaminants but will handle the bio nasties.

hey im new here and generally VERY new to building a better psk kit and such so i got a newb questions... whats a BOB that was mentioned here?

BOB = Bug Out Bag

Basically a large, well equiped PSK - prepacked and ready to be grabbed at a moments notice.

there are small filter which can be carried as a backup like the gatekeeper ( picked on up on a discount box for € 3 ! ) or filter/purfing pen which are pretty small too.

NY Rat, here's my BOB (Bug Out Bag) list. There are also many others out there for reference:

http://www.roblester.com/rob/bugout.htm

What kind of storage time can I expect from a full cambelback left in my trunk, Do winter summer shelf lives vary?
Thanks
Scott

My experiance with camelbaks has not been good as far as storing water. I'm not sure how long I kept mine full but flaky stuff, like the liner delaminated, formed. I still use and love my camelbaks but I don't leave water in for days on end. The platypus bladders work well for that. I've found old platypus bladders in bags that have had water in them for almost a year and it was still fine. Large gatorade bottles seem to work well too, for storage, because they are big and have a handle.

Kosttab: Good question. The real issue with water tends to be weight. There is a very real limit to the amount of water you can carry. You can comfortably carry a quart to two for an afternoon hike. You simply cannot carry enough for an extended 3 o4 4 day hike, nor are you likely to have 8 or 10 gallons on hand when an emergency arises.

Boiling is an option. However, you have two choices. You can carry fuel or you can find fuel. Carrying fuel isn't very practical. Carrying a small amount for cooking is okay, but the fuel required for boiling all drinking water as well as cooking is not practical. Nobody wants to carry a ton of naptha, keorsene, whatever. As for using natural fuels, a lot of wet weather hiking has taught be it isn;t alwasy practical. If I'm hiking, I want to hike, not spend all day finding fuel to boil water. If I'm surving, I do not want to spend all my time trying to find fuel to boil water. Finding fuel, making a fire, keeping the fire going, boiling the water, letting it cool and pouring it into a container is a 45 minute job. I can unpack,filter and be gone in about 3 minutes.

Good filters aren't cheap, but they offer significant advantages. I own a Katadyn ceramic filter. Weighs something like 16 ounces. In the North Eastern US, where adirondack streams are plentiful, this 16 ounces of katadyn means I have nearly unlimited drinking water. And my water load is about 2 pounds (1# of filter and a small amount of filtered water).

The cheaper chemical/carbon filters work good, but have limited lives. They can filter a set amount of water, but once used, even if only for a quart, they have a life limited to a few months. The cermics are expensive (and do not remove chemicals) but are practically unlimited in life. Dry it out, pack it away, and its ready for next year.

There are several types of water filtering 'devices'.

Actual "filters" force water through porous materials, removing or trapping particles of dirt, bacteria, etc. They work on a physical removal prinicple. Cheap Filters remove big chunks of junk (2 microns). Really good filters remove much much smaller chunks in addition to the big ones (0.2 microns).

"Purifiers" often work by chemical means. In addition to a certain amount for filtering, they also introduce some form of chemical agent that kills assorted nastys.

There are pros and conc to each side. I like the extended life of a good ceramic. It does not "kill" the little creepies, but simply strains them out. Main systems are now hybrids, using both filtering and purification.

Whether you filter or purify, these units beat boiling hands down.

Forzenny,
I agree with you on many counts. It is unlikely that anyone will want to carry much more than 2 gallons of water on their backs and that only at the expense of not carrying other needed supplies. Good filters are worth their cost and weight in backpacking scenarios. Chemical purification is adequate but again consumable.

OTOH, (you knew that was comming <img src="images/graemlins/wink.gif" alt="" />) I don't agree that you can't plan ahead and have 8 - 50 gallons of water on hand when an emergency strikes. In any building you might be in it is a simple matter to get a couple - many bottles of spring water and store them under a table or desk against a rainy day. I have 20 gallons in my basement and my office has two water bubblers that each have a supply of 20 - 5 gallon bottles lined up beside them each Monday. Friday there is always a few left. My car has two gallons in it as does my wifes.

Also I don't agree with the lack of utility of boiling in a survival situation. If you are lost and down travelling isn't always the way to go. If you are stationary it isn't at all difficult to keep a fire burning and for many reasons that is the best thing to do. fires provide signal, warmth and cheer as well as allowing boiling of water supplies, sterilization of medical and other cutlery and clothes (necessary for the women after a few days) and cooking of foods. Many survival situations will involve self-extrication and in those scenarios the filter or puri-tabs will shine. In scenarios with a more stationary "wait for rescue" flavor a continually burning fire is a welcome addition to the camp.

In the BOB / Evacuate scenarios - not all are on foot. Certainly if you are on foot there is a realistic limit to what water you can carry but even in those scenarios there is a limit to the water you need to carry. All you need to carry in an evacuation scenario is enough to travel quickly and as lightly as possible to the evacuation destination. (presuming enough planning to ensure that the destination has a supply closet with water in it. In such a scenario all you need to carry is a maximum of a gallon per person - immanently do-able - and the time taken to process water with chemicals, a filter, or boiling is too much of a slow down. In evacuation scenarios speed of travel is the primary concern. In a vehicular evacuation there is no serious limit to the water you can carry. 20 gallons fits in the trunk along with the bob and if you have a pick-up or jeep so much the easier. It is just a matter of planning to be able to load and go quickly enough and plan on packing the water as well as the firearm.

So the only time that the water carrying capacity is a real concern is in the long trail scenarios where you will be traveling by foot for long distances / times. This is a real concern for backpackers and hikers but not so much so for preparation to survive unexpected disruption of your plans by extreme circumstances.

Just my $0.02.

Good points MiniMe.

I too have water on hand. There's six 5 gallon water carriers at home, each sterilzed and sealed for long term storage. There are also a dozen or so gallon jugs of spring water. And the generator is routed through a Generac auxiliary panel, which fires my well pump. I have plenty of water on hand.

There are times when gathering wood to fuel a fire is fun. I often stop to have a leisurely woods lunch over an open fire. However, I have also gone 'primitive" camping a few times, and have found myself in situations where suitable wood was very, VERY scarce. I can distinctly remember hunting around for an extended time, finding a handful of dry wood, and nursing it through a steady rain trying to boil a little water for a bowl of oatmeal. It was a challenge.

As a hiker/hunter a woods lunch is fine and dandy. However, in a survival situation I want every card in the deck stacked in my favor. Likely "situations" for me include broken legs, twisted ankles, and other "mobility" issues. Crawling to water would not be fun. I certainly do no wish to compound the situation by crawling ever increasing distances for more and more wood.

I really am of the opinion that carrying water is always smart. I continue to carry some form of water filter/purification as well. The Katadyn filter makes it into the back pack, and the PSK has tabs.

Of course, my situation is dependent upon my geography. I seriously doubt I'm ever more than 100 yards from water. There is always a stream, puddle or pool. However, I recently hiked in Arches National Park in Utah, as well near various areas around Salt Lake City. It was 106 degrees, and dry as a bone. Any filter/tabs/purifiers would be nearly useless. I had hard decisions to make. Water become a much more important issue, so other equipment was excluded to make way for more H20. The usual rain coat made way for another quart. And early mornings at higher elevations had a surprising amount of moisture on foliage, so a sponge was definitely a good idea...

Deciding to rely on boiled water is possible, and it may be "doable". However, it sort of strikes me as short sighted. It's kind of like relying on finding flint and knapping a knife when the need arises. There are easier, more reliable alternatives.

Frozenny

I completely agree that to rely on boiled water (or for that matter any ONE of the alternatives) is not a good idea. As I pointed out in my earlier post I believe that there are scenarios where each method has its place. I carry PA tabs in my PSK and a filter and PA in my BOB because I cannot predict what scenario I might face. I also carry multiple methods of starting fire because in many scenarios the ability to get a fire going is imperative for warmth and protection. If I were in a stationary "wait for rescue" situation and I was in a location where firewood was accessible I would certainly start a fire for signal, warmth and protection. Once I had the fire going I would probably use the Foil wrapped around my PSK to boil my water rather than waste the precious few PA tabs that I had until it was necessary to do so. A filter doesn't fit in my PSK though I have been considering adding one of those McNett filter straws to my EDC. In my BOB, if I have it with me at the onset of the situation, I have a Katahdyn mini filter. This is one of the ceramic filter combined with carbon core type that filters at a fair pace. (I can filter two liters from a stream in the time that it takes my knees to recover during a rest stop) . If I have that with me I will certainly filter rather than boil since it is easier, just as good, and would allow me to use the foil for other things or economize it until I needed it.

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To plan of relying on one method and not bothering to prepare for scenarios where that method will not work is niave or foolish. Many who come here asking questions are niave - that's why they ask quesitons. It only becomes foolishness when they are answered well (as you have done) and they continue to persist in self imposed ignorance.

Many start out thinking that by getting in shape and knowledgeable they will be prepared and all they need is to be able to recognize some edible plants, a good stout knife and a well trained body and they can handle anything - Rambo style. Maybe so Maybe no. I wouldn't want to try it. I have redundant methods for water processing, fire starting, cutting, tool improvisation, lumbering, cooking, harvesting, trapping, fishing, all based on the simple tools that can be crammed into an altoids box and carried around by anyone everyday. I am not carrying these things in ignorance but have used them to the point where I understand how they work and am facile in their use. I am no more comforted by my gadgets than I am by my excellent physical conditioning. Being forced to live outside unexpectedly without all my nice Ultralight High-tech Backpacking gear and dehydrated rations and bear canister would suck! But I am prepared to do that with what is in my pockets or without it. I can start a fire with what nature provides, make a cup for boiling water out of birch bark or some similar substitute, trap and harvest using only the tools available in the wild but I'd rather have my snare wire, wire saw, tin foil, Xacto blade spear, fishing kit, Spark-lite, tinder-quick, hurricane matches, iodine tabs, water balloon, twine and paracord, and trashbag - tarp.

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BTW, has anyone got specific information on that McNett filter straw regarding what it claims to filter out and what it doesn't?

Thanks everybody for the great feedabck. Now I know what you mean. I have heard high praise for Katadyn water filters but i do not know if I can find it in Greece