Water purification

[Metal mug]

Does anyone have any tips or advice to share about water purification? I found out recently that if there are traces of silver in the water it decreases the pathogens in the water by a large percentage.
:camping:

[chris grace]

I use a couple of methods,first is boiling then puritabs and neutralising tabs and then a katadyn hiker filter.Sometimes,depending on where the water is and what is around it I'll use a combination of the above methods.

[resnikov]

I start with a milbank bag to get any particles out of the water, then boil it. Should be fine for most water in the UK so long as its not from a source that has heavy metals or chemical industries near by.

[MikeWilkinson]

I'm just in the process of experimenting with DIY water filters and boiling/chemical treating afterwards. I've used commercial filters before and don't really consider them worth the payout.

I've done a fair bit of research, physical filters need to be able to remove particles as small as 0.02 microns to be classed as purifiers, this size would remove cysts, bacteria and virus'.

Things like Milbank bags and most filters can filter down to around 0.5 microns, this would still allow most bacteria and virus through and so filtered water still needs to be boiled to kill of biological contaminants.

Chemical contaminants require absorbtion by another media like activated carbon and a really slow feed through to remove heavy metals (about 4mm a min to reduce levels by 80%) This is obviously far too slow to be really useful for bushcrafters but any higher rates the effectiveness reduces considerably. Considering the chemical content of most good springs and run off in the moors and woodlands in the uk, 20/30% reductions are probably all thats needed.

My current filter experiment uses a synthetic wool to prefilter big rubbish out of the water, followed by a 0.5 micron glass fibre filter and then some activated carbon before another 0.5 micron filter. I use a small outlet pipe to slow the water flow down and make the best of the carbon.

I then treat the water by either boiling (proper rolling boil for a 1 minute) or use a chemical treatment. Prefer boiling though.

There is lots of interesting debates about boiling water and for how long, but a lot of medical research has proven that just getting the water to a full rolling boil will have killed of most nasties, the extra minute just makes sure. (At higher altitudes a longer boil is required as the boiling point is lower and at really high altitudes wouldn't be high enough to kill of the nasties).

For long term filters water supplies there are some brilliant designs/methods in use in the third world including sand filters and ceramic pot filters (one of my favourite designs)

Once I've got something that I'm :) with I'll post some pictures of the final DIY filter.

I forgot to add, Silver does improve the purifying of the water, but it would be costly to use as the main filter component, I believe it is only used to maintain ceramic filter surfaces and reduce the amount of bacterial growth on the filter itself.

[resnikov]

Would be very intrested to see you final product and hear how it goes.

[MikeWilkinson]

Will keep you posted.
It all works well in the old test lab (garage), just need to find a good of way of packaging it up for use in the field. I'm thinking of taking a couple of pieces of overflow pipe - about 50mm each in length, fill one with the wool, the other with the carbon, and use a straight coupler to join the two with the glass fibre filter snugged up in between. Then band the whole lot to a hole in an old waterproof stuff sack for the untreated water an have a length of tubing with s valve on the end to fill my Billy.

Just need to find time to put it all together.

[Ashley Cawley]

I'm just in the process of experimenting with DIY water filters ..Half expected it to be birch-bark based for a second there! :p

Sounds like an interesting project Mike, one I'll be keen to see :)

I personally just collect from a clean a source I can find & then boil. I should probably pay more attention to heavy-metals etc.

[MikeWilkinson]

Hmm, good point Ashley, I wonder If I could get some Birch in there somewhere... :p

[MikeWilkinson]

If your interested in why we filter and to what level, then have a good look here :-

http://zenbackpacking.net/WaterFilterPurifierTreatment.htm

The Zen water page like the Zen stove pages seems to have the best overal summary of everything I've read so far, and really gets you thinking about whats in our water.

[paul standley]

I've played around with several DIY filter component combinations including using Brita filter catridges, loose charcoal, various grades of filter fabrics including cotton wool balls and cotton pads in various holders and containers. All work well to filter out particulate matter.

Then it's a good boil or a chorine tablet but not keen on the chlorine after-taste. I do always carry a few chlorine tabs in the cook kit just in case.

Had fun making the filters but I think that for ease of use and size, something like the Katadyn is the way I'll go in the future.

Just purchased a Katadyn Hiker filter/purifier last week so I'm keen to get out and try it. Currently snowed in big time in Wales so can't get anywhere at the moment...!

[MikeWilkinson]

Hahaha!!! (Evil genius laugh)...

Ashley, I have found this :-

http://www.wildwoodsurvival.com/survival/water/lswbirchbarkfilter.html

Just call me Mr Birch!!

[gemgenie]

Has anyone tried the Aquatap?? They look interesting due size and flexability (use it as a waterbottle while walking and then to top up you bladder when neccessary).

Would be interested to hear from anyone who has experiance of it.

[MikeWilkinson]

Quick update, got hold of a pipe repair fitting and pipe reducer - all in one package, filled one half with wool inserted a 1micron filter in between and then activated charcoal in the reducer end.... .... took forever to drip a litre through (nearly all night), the 1 micron filter clogged up too quickly. Removed that and had no problems, wool did a great job of removing big particulate matter and the AC seems to swell a little and really slows down the water flow, meaning longer contact and removal of metals. Only thing is I cannot guarrantee the 1 micron filtration anymore!!! But boiling takes care of all the micron, sub micron beasties so think I'll use it as is. Next step field tests!!! (I'll take bog roll just in case).

[Fletching]

I'm thinking of experimenting using a plastic funnel with, in upwards order, a small piece of Scotchbrite pad scrunched into the narrow end of the funnel, the contents of a (broken open) Brita refill for the AC topped with two circular pieces of Scotchbrite.

Any suggestions?

...still got to beat the Millbank though!

Steve

[swkieran]

how did our ancestors purify their water,they had nothing no brita filters, pipes etc

[MikeWilkinson]

There was little need to purify water, as very little mass grazing land and certainly fewer pollutants. There main problem woud have been bacteria and virus'. Our Digestive systems have become somewhat weak due to all our sanitation - they naturally had better resistance to certain bugs, and boiling pretty much kills the rest.

You also have to look at the mortaility curve for our ancestors - died younger from diseases that today we have eradiated or can control.

Today we have toxic heavy metals released during mining and other landscaping, Chemical pollutants from factories and engines, Mass farming alonging water courses and up on the moors and dales - which leads to more fecal matter and dead animals in polluting near source. Fewer trees and forests to naturally clense and filter water through root systems. You only have to look at places like northern canada and siberia where you can probably still drink direct from mountain streams and brooks. We have really screwed ourselves really when it comes to clean water.

[swkieran]

they would of used the appendix organ i think must be there for a reason originally,it serves no purpose in todays humans

[Marvell]

This is something on my list to blog about. I'll post up here when I get it done.

Something to note is that before boiling or puritabbing, especially chlorine, the water has to be filtered, or it's not as effective.

[FrenchBen]

I often go practise bushcraft skills in a little piece of woodland not too far from home and what I miss most there is drinking water. Always take a filled one-liter plastic bottle with me but I'd like to experience collecting running water.
I noticed several draining ditches in those woods often containing water. Sometimes, bunches of dead leaves form a sort of a dam that retains water. Downstream the dam goes a little stream of water.
As there are no intensive agricultural activities around nor heavy metal pollution (I think...) would you say it's safe for me to collect water, filter raw material from it then boil and drink?
I'm going there tomorrow. Take my camera and bring you back a vid of the place if you want.

Concerning first filtering of particles, do you think a coffee filter would do the job correctly? (maybe two or three of them you put in one another...)

[FrenchBen]

I often go practise bushcraft skills in a little piece of woodland not too far from home and what I miss most there is drinking water. Always take a filled one-liter plastic bottle with me but I'd like to experience collecting running water.
I noticed several draining ditches in those woods often containing water. Sometimes, bunches of dead leaves form a sort of a dam that retains water. Downstream the dam goes a little stream of water.
As there are no intensive agricultural activities around nor heavy metal pollution (I think...) would you say it's safe for me to collect water, filter raw material from it then boil and drink?
I'm going there tomorrow. Take my camera and bring you back a vid of the place if you want.

Concerning first filtering of particles, do you think a coffee filter would do the job correctly? (maybe two or three of them you put in one another...)

[Fletching]

Concerning first filtering of particles, do you think a coffee filter would do the job correctly? (maybe two or three of them you put in one another...)

See if you can get your hands on a Millbank bag (http://www.endicotts.co.uk/product_info.php?products_id=1360) (or the French equivalent, if you have one). Will last you for many years.

Steve

[FrenchBen]

If your interested in why we filter and to what level, then have a good look here :-

http://zenbackpacking.net/WaterFilterPurifierTreatment.htm


Amazing link Mike, thanks!

Steve, thanks for the advice. I was just wondering what millbank bags were when reading the thread. Got my answer now. Is it really as durable as many years??
Absolutely gotta try and find one in France.

[Fletching]

Is it really as durable as many years??

If you look after it, yes. The ones we buy are ex-issue and mostly used to start with.

[MikeWilkinson]

Hi Ben,

If you like that then for more links like that, take a look at this thread -

http://www.naturalbushcraft.co.uk/forum/showthread.php?244-Resources-for-Budding-Bushcrafters-and-more-advanced-folk.

It pretty much covers every online resource I use for all things bushcraft, so if you have a question and don't mind doing a little research, then this is the place to start, Zen and Wildwood probably contain the most useful data.

Glad I could help.

[GaryBeaner]

On the subject of water additives..........it's not common knowledge that flouride was used in high levels in concentration camps as a sedative, and was also tripled in concentration in the water supply(sanctioned by Mrs T) during the northern Ireland riots of many yrs ago.

[Ashley Cawley]

Hahaha!!! (Evil genius laugh)...

Ashley, I have found this :-

http://www.wildwoodsurvival.com/survival/water/lswbirchbarkfilter.html

Just call me Mr Birch!!

LOL... Only just noticed this Mr Birch! - You made a Birch quilt-cover yet? :ashamed:

That's one thing on my list to get a Millbank bag.

[comanighttrain]

On the subject of water additives..........it's not common knowledge that flouride was used in high levels in concentration camps as a sedative, and was also tripled in concentration in the water supply(sanctioned by Mrs T) during the northern Ireland riots of many yrs ago.

no way?

[GaryBeaner]

Yes way comanighttrain.
And while I was working for the water company, we used to sell a bottled wated called '464' because it came from a borehole 464 ft deep and had been 'naturally filtered' etc etc etc. You could buy that water for about 80p a bottle. At the same time, we were using the same water from the same borehole and treating it, filtering and chlorinating it, then providing drinking water to peoples homes with it. So you could buy it in bottles for 80p, but if we put it through your taps without complying with all the regs they would've sued our bottoms! Funny but true!!!