Bushcraft Basics Ep09: Water Filtration & Disinfection

Hi there guys it's Mike from MCQ Bushcraft here and welcome to episode 9 of Bushcraft Basics. In last week's episode, episode 8, we had a look at some of the pathogens and contaminants that are in our water supply and really last week's episode was just designed to arm you with a little bit of knowledge so that you can approach products a bit more subjectively and start to work out different methods and systems of actually making water safe to drink. A lot of the time when you see a product you can look at the description and you can take it as gospel but what you don't actually realize is some of the reasons behind why they can say they do certain things is down to various circumstances that take place that can be fairly common but are not always possible and it just gives the creator of the device a little bit of artistic license on being able to say what it can and can't do. A little bit like a CV for example that someone would write for a job application you know you can take liberties on certain things and make them sound far more interesting than they really are. It's that kind of mentality really in some respects that you've just got to be able to see through when you're looking at products and what they claim to do and in this week's episode we're going to be looking at a range of different products. I have some products with me today. We have gravity filters, straws, different chemical treatment methods, even basic methods that are actually used in the field and ceramic pumps as well and hopefully these products will give a good representation of the kind of common technology that's out there that you can find on the shelf and we're really going to go through them today discuss their pros and cons and I'll show you how to use a few of them as well in the field. The first kind of filter that we'll have a look at are gravity filters and gravity filters are popular, very simple technology. We have two different types of gravity filter here that use different styles of filtration if you like. This one here is a very popular one and the reason they call them gravity filters is you can have a body of water above in a container and it'll be drawn through the filter and clean water will come out the other end so essentially they can be hung in campsites and used as clean water sources to go and collect water from and they can be very useful in that context. A lot of them come with containers like the Sawyer Mini and you can also have a straw on the end as well that goes into the container like this and you can draw water up through it so you can have an emergency supply of water that you can carry with you but let's have a look at the Sawyer Mini. The Sawyer Mini is a very popular filter that you'll see quite a few people using in this day and age simply because it's so small, it's so light and it's got a good proven technology behind it and Sawyer are a reputable company. This one here can filter up to 100,000 gallons of water which is about 450,000 litres so it has a very considerable ability to filter an awful lot of water for you but that's provided that you look after it. This filter here is rated at 0.1 microns absolute and absolute means that it's tested under absolute conditions and it should be functioning at 100% efficiency not letting anything through 0.1 microns or above. It has no pre or post stage filtering process it's just one hollow fibre membrane filter right through from head to tail and what that means is it's just a long canal of tubes which is a very accurate technology and widely used in in the modern world so the water just passes through a length of tubing and any particles 0.1 microns or above would not be allowed to pass through the actual filter and they'd be caught in that hollow fibre membrane. Another important feature about filters like this especially with hollow fibre is they require to be back flushed after use and what that means is that once you've consumed water through or contaminated water through either the bottle or directly out of a river in whichever context you're using it for you need to then back flush it and what this filter actually comes with is a tiny little plunger that you can fill full of clean water or even air if that's all you can use and you can back flush the filter and what that does is it's said to improve the life of the filter to up to 85 percent because effectively what you're doing with hollow fibre is you're just catching loads of particles and all those kind of small holes can be can be blocked up over time and it reduces the flow rate of the filter so by back flushing it you fire back out all those particles and actually clear those pathways for it to be used again the next time you wish to have drinking water. As we talked about this filter doesn't have any pre or post filtration methods and it has no active carbon in it so the actual taste of the water won't be improved it's not going to deal with pesticides or herbicides or reduce them in any way whatsoever unless they're bound to larger particles it's not essentially going to tackle industrial compounds that might be in the water supply again unless they're bound to a larger particle that's 0.1 microns or above so that's the disadvantage with a filter like this if you're in a part of the country or in a part of the world where they're using a lot of herbicides a lot of pesticides there's a lot of industrial factories around a filter like this probably isn't the filter for you because it won't tackle those kind of contaminants that are actually in the water and reduce them enough for you for continuous safe drinking which is a bit of a shame if they added an active carbon element to a filter like this even a replaceable capsule that went on the then it would probably be far more useful in an environment like that but that's not to say that you aren't capable of making your own by using part of a plastic bottle and screwing it on the end there if you do have this filter at 0.1 microns this filter is basically going to filter out quite a lot for you quite a lot of the pathogens that cause a problem in the modern world it's going to deal with things like e.coli salmonella cholera it's even going to be able to deal with the spores from anthrax it's going to be able to deal with protozoa like jardiya and cryptosporidium even because of its pore size essentially at 0.1 microns it's going to be able to handle all of those things quite happily and it won't be able to deal with viruses but do bear in mind that a lot of these things can bind to particles in the water bits of feces bits of soil in turbid waters so if you are concerned about those kind of things then there is a possibility that a filter like this might be able to deal with the causes of some of those problems simply because it will be able to filter out larger particles that things like viruses and pollutants will bind to when they're actually in the water but i would not rely on this filter if that's a very common problem and at risk in your environment because it's simply not geared up to deal with those kind of things and also a very good point is when you're using this filter and you're drinking from fresh water if waters are very turbid so they're full of sediment it's ill advised to actually put this water this filter into the water and drink straight out of turbid waters because you'll drastically shorten the life of gravity filters and filtration straws in that context it's always advised that if you can pre-filter the sediment out of the water first then do that because you'll extend the life of the filter this is a filter that i've been using for about the last three years and it's almost at the end of its life and this is the webtex inline filter once again very similar to the soya mini in terms of its design it can actually be like the soya mini put into the lines of a camelback or water bladder system making it quite a useful filtration system if you're on the move and you only got time to pour contaminated water into your water bladder the filtration capacity of this one is far less than the soya mini it can filter about 1600 litres which is about 350 gallons so it can't filter nearly as much at all as this soya mini here at 100 000 gallons or 450 000 litres but this one's a pretty robust filter and it's got some good features to it this is uh rated at two microns so it's a lot larger than the soya mini in terms of its pore size and it's a tortuous path filter and what that means is unlike the filter in this one which is a essentially tube so a hollow fiber membrane this one has a maze of infrastructure that the particle must travel through so it has to to go through lots and lots of little pores and canals which essentially increases the ability for particles to get captured in the filter itself one thing that webtech say about this filter is that it contains pre and post filtration methods and also epa media purification media that will outlast the life of the actual filter itself it doesn't actually state what that is or what it can do what it's designed to do but it does go on to say that this filter will improve the taste of the water almost immediately remove things like pesticides herbicides other organic matter um solvents from industrial waste so it makes you believe that this filter has some kind of active carbon element to it and that might be the case it's a very common thing used in filtration if anyone's not familiar with active carbon it's carbon that's been specially treated and it becomes highly absorbent incredibly absorbent material and just for an example one milligram of active carbon can generally absorb in excess of about 500 meters squared so very absorbent stuff it's not the only thing used in water filtration it's not designed to remove microbes but it is designed to remove things like herbicides and pesticides and water that's been treated with chlorine will obviously instantly taste better once it's been through an active carbon filter so it does make you believe that this might have an active carbon element to it it doesn't say that in any of the advertising and none of the information provided out there actually points to that but it may be the case which is a good a good sort of feature on the filter really if this filter can remove things like or reduce i should say herbicides pesticides compounds that are really going to be considered toxic or pollutants in the water supply then that's a fantastic feature of the filter and i think it's one thing that this one has that the soya mini doesn't but in terms of the kind of things that it's going to filter out you've got e-coli you've got salmonella it's going to be able to deal with them it's easily going to be able to do with protozoa which are quite large around about five microns and this is two microns and it does say that it can do viral causes as well and what i think it means by that is pieces of faeces and bits of soil turbid waters large particles that essentially viruses bacteria and protozoa can bind to even pollutants that would get caught in this filter so it should really be able to handle everything you want it to but again it's not the filter for you if you live in a part of the world where viruses are a problem you wouldn't want to rely on just this and you might want to pair it up with something else like chemical treatment like chlorine dioxide or chlorine or iodine that could get rid of viruses or boiling water for example so the pair of these together could should be able to tackle most things out there in a lot of different parts of the world other types of filters exist with similar technology inside them this is a life straw and it's a very popular filter designed for emergency aid and very very useful bit of equipment actually quite small really considering what it can do and worth keeping one of these or of something of a similar design actually in your kit for when you really need water but it's safe to say that these products here can be used in a similar way these are obviously gravity filters but they can be used as straws and webtex design a range of filters with the same patented filter design inside just in straw devices so in theory this straw here can actually still function as a gravity filter and i would just classify it in the same context in most in most cases simply because it works in the same way just you're sucking water through it but life straw do make one which is exactly the same as this with an adapter on the front that works a little bit like these ones here so it can be connected up to a water source by a camp area and then this plug is taken off the bottom or when it has a small valve on the other one and water can be set free that way so the technology is very similar it's just that the cases that they're put in are designed to adhere to different markets but life straw is quite a popular one and one of the most well-known straws that are out there its filtration capacity isn't as good as these two here in some respects this can do 1000 liters which is about 264 gallons of fresh water and this is a hollow membrane filter again a hollow fiber filter and it simply just has tubes running all the way through but it does have a pre-filtration system very very basic just a piece of foam because obviously with these straws a lot of the time you're sucking water out of turbid waters and this part here is designed to just remove the turbidity in the water and it can actually be washed as well but not too easily in some respects the webtech straw actually has a removable pre-filter in there which is cotton wool it can be taken out and replaced or washed to get rid of sediment in this one it's a little bit more tricky than that with a lot of these products that we've looked at this morning these are very basic filters and they're generally inexpensive and they feature a lot of the same technology a lot of the same reliability and they're good bits of equipment to have with you out in the field if you need to filter water the disadvantage with them is they're generally low capacity especially if you don't look after them and the maintenance side of them is very difficult they can't be maintained cartridges can't be replaced and they can be damaged quite easily the nice thing about these straws with the pre-filter is obviously you can drink straight out of turbid waters if this water was quite flooded and muddy which it isn't at the moment i would use this filter by drinking straight out of it if i had to but there's always advice there that says that you should collect water filter it through a rag and then drink out of it to extend the life of your filter this one along with the two other gravity filters we looked at this morning requires blowback effectively so once you've drunk with it which i'll drink out of this stream now i can show you so it doesn't take long for the water to actually start coming up through the filter you just have to keep that pressure on but it's actually pretty heavy now and i can feel there's a lot of water inside the filter so what it advises you to do is to blow back through it to clear the particles and sediments out and obviously get the water out as well so you can put it back in your kit easier said than done that's pretty much it the only water remaining inside now is in this piece of foam at the end but you should be able to get a bit of the water out of that by just flicking your wrist there we go this life straw here although it has quite a low capacity compared to some of the other filters we've looked at today and that we will look at it's still very useful and quite a reliable piece of equipment designed for aid for people who need it and this is going to be able to deal with pretty much everything you're worried about out here that could be pathogenic and make you ill so things like e.coli salmonella cholera it's also going to be able to deal with anthrax spores as well it'll be able to deal with protozoa like jardia and cryptosporidium but because it has no active carbon element to it it's not going to be able to deal with contaminants that are in the water supply from herbicides pesticides agriculture and also industrial solvents so unfortunately another filter would be right for you if those are the things you're concerned about in your area you've seen some of the things that the sawyer system comes with comes with this bottle we have a straw and we have the filter and the plunger i don't have with me in the field today but that's very good for forcing water or air back through the to push out any sediment water's a little bit better because it's going to move things up a little bit more but in terms of what we do with the sawyer very very easy system to use and really for me just an emergency system we've got a nice stream here not turbid at all it comes out of rock further up so this is a fresh spring and it's um it's very clear and with water like this i'm not too worried about things like herbicides pesticides and contaminants there are other places that i go which i am worried about that because they're near areas where there's a lot of farming and i know crops are grown and i've seen them doing spraying and i know that that gets into the water supply there and i'm always very dubious about drinking water from those areas and mindful that i'm probably getting that kind of um i suppose contamination inside my body but then we do get a lot of that from the food we eat off of the shelf anyway so it's um it's best to minimize it as much as you can but it is very difficult it is very difficult but this stream here is an ideal stream that i would drink from if i were out in the woods or the wilderness i said in the last video i've drunk straight out of this stream and i have and i've not been ill i've done it a few times but i generally go much further up to where it's coming out of stone out of not a wall of such but a natural wall out of the source and it's really clean there on its way down there is potential that things can get in pathogenic bacteria protozoa from animal feces and other contaminants as well but in this water here really what i would do if i was going to approach this is i just collect it straight with my bottle and boil it on the fire and that's generally what i would do with a stream of this quality but if we were using the soya mini for example let's say we need some water in an emergency it's really easy to do you want to put a bit of air in the bottle first by blowing into it you can always face it downstream so you can avoid sediment but this is a very clean water you can take your soya mini pop it on your top there avoid getting any water around the mouthpiece there because of contamination you can pop the cap off and drink so it's not a bad system for actually getting water it's um yeah it's okay i mean i don't really i don't really rate any of this this is the bit that that really matters and it can be used in other ways as well for example we can have a bottle here like this nalgene bottle and actually squeeze the water into the bottle just like this so once we've used this if we have the plunger system we could connect that to this and actually force clean water back through the filter flushing out all the particles you can actually blow on it it's not very effective because it's 0.1 microns and that's a very very small pore size so pushing air through that can be a bit of a struggle but most of the water has actually come out of it there we go so really you do want to carry the plunger part with you and that'll probably make life easier and that way you've got a bit more of a dedicated water purification system on you but not bad not bad if you need clean water it's a good option for you but for me it's more of an emergency piece of kit for a med kit so we've had a look at a few gravity filters and straws and those are very good budget systems to use if you're just looking for something to keep on you while you're out in the field in an emergency or if you want clean water a lot of the time i would use something like this as a permanent system for filtering water and i'd put other systems around it so this would be part of a camelback for example and then that setup would be something that i constantly use with dirty water and use that to actually clean it and the nice thing about a camelback as well is when you have the excess piping with some water in it you can obviously then blow that back through if you have this on your shoulder for example a bit of piping there with clean water in because it's come through the straw by blowing back you're putting that clean water back through filter into the bladder and that acts as your blowback system and that way you can maintain the filter through a system like that and it's a little bit easier it's a little bit more self-contained but cleaning an actual water bladder out is another story and it does need a bit of maintenance when you're back at home and you're out of the field there are different designs though some of them very easy to clean others a little bit trickier some of the older ones are quite tough but let's have a look at a ceramic pump filter because they can be quite good dedicated systems if you're always using filters out in the field to purify water in here we have a katadyn filter and katadyn produce some very very good filters you have um ominous as well but katadyn make some very very good filters this is probably one of their better ones in terms of actual build quality not function believe it or not but this is the katadyn pocket and it's a very robust filter probably one of the most robust filters i've ever seen really built to last as a lifetime guarantee and really is an incredible bit of kit it's all metal construction apart from this shell here which is a very thick plastic a lot of people complain about that and say it should be metal but when you're up in the mountains and you're pumping freezing cold water this being plastic here actually keeps your hands a bit warmer and makes it more user-friendly than if it was metal and it would be freezing if it was this is a ceramic pump filter so you pump it like this it has a pre-filter on the end just here for large sediment you can see it's quite a quite a good one actually it's a very fine white mesh that takes a lot of sediment out of the water you've got a piece of foam there a bit like a float on a fishing line to adjust how deep the water is effectively so you're not taking water off the surface which is where most of the bacteria you're taking it a bit further down in cleaner waters and that's the idea behind it quite a long tube as well so you can get a bit of reach into the actual stream or water source you're using but we've got the outlet pipe there you might wonder why there's not the hose on there at the time being it's because it's kept in a sterile bag or in a bag away from any of the other parts of the filter simply because you don't want contaminated water getting on the outlet hose that's going to be going into your container so it's often kept in this bag here on its own and then put on when needed if we take this top part off here the filter will come apart you can see there's the ceramic filter inside you can see we have bearing valves in here as well which is a really nice little feature the components on this are really well machined and they're very solid and this filter is cleanable this is a 0.2 silver ceramic micron filter and this has no active carbon element to it just has a pre-filter the thick sediment and then this ceramic filter here but the thing that makes this ceramic filter different or what Cater didn't obviously talk about when they're selling this product is that it can be cleaned they provide you with scotch pads just like this and you can clean the filter up and return it back to its pale color and the filter obviously decrease in size as you do this so they give you a measuring device and when you put that over the filter if it can fit perfectly over the filter then you need a replacement because the depth of the filter isn't deep enough to guarantee that bacteria and protozoa can't get that's the idea behind this element here but this filter here can do 50,000 litres or 13,000 gallons so it's got a hell of a capacity on it for a ceramic filter and very well constructed you can see this is quite thick plastic here quite well made i was quite impressed with this this isn't mine it's one i borrowed but i have used these before used one of these in norway and it was pretty good although it wasn't really necessary because the water is very clean up in the like a lot of filters if you're dealing with turbid waters with lots of sediment then pre-filtering is always advised to improve the life of the filter but the nice thing about this one here this sediment filter is that if you have a bandana or a piece of cloth it can always be wrapped around a couple of times to act as a an even better pre-filter before it gets into the ceramic filter so that's always something that you can do with filters like this so you can see i've put the pre-filter in the river there the float's not really doing an awful lot the river's not deep enough really but in deeper waters it's uh it's far easier we're just going to expel about half a litre of water just to get rid of any ceramic dust and this is a recommendation by katadyn and you have to do this with quite a lot of ceramic filters that should do so we can now take this spring here and clip it in the bottle and i usually pinch it between my my legs there because it doesn't stand up too well once you finish pumping the water out you can take off the outlet pipe this will be full of clean water i generally pop that in a top pocket somewhere out the way just so you're not going to get it contaminated by by the water not that there's a big issue in this area here sometimes you can be a little bit overcautious with this sort of thing and we can just pop this down and obviously we've got quite a bit of water got 600 milliliters of water there and i was pumping the filter for probably about 30 seconds so that's not too bad so in terms of what this filter is going to be able to do for you what it will do what it can't do it's going to be able to take out pathogenic bacteria out of the water and it's also going to be able to take out protozoa so things like jardia and cryptosporidium e.coli salmonella cholera also anthrax spores as well so anything in terms of you know the worry around pathogens is really neutralized by a filter like this it's going to be able to do quite a lot it's very robust so it's for long-term use if you carry a spare filter then obviously you've got something that will last you a very very long time downsides are it's quite big and heavy and there are smaller filters around that can actually have a bigger capacity and are simpler to use but it really depends on what you're looking for this is really a long-term filter and quite a good one as well lifetime guarantee very solid but what it won't do for you it has no active carbon element to it it can't remove things like industrial solvents pesticides and herbicides and other sort of pollutants from the water supply so if that's a problem for you this isn't the filter for you because you're only going to have to run it through an active carbon filter to actually get rid of that and it means you'd need another filter in the field with you so not really a sort of jack-of-all-trades in that respect i think the katadin combi is a better filter than this it's cheaper and it has a ceramic filter but on the inside of that has active carbon and that will actually take out herbicides pesticides industrial solvents and other toxins from the actual water supply other organic compounds that are in the water so that's actually a better filter than this one if you're worried about herbicides and pesticides but again this filter is not geared up for things like viruses there are special filters out there that are cheaper than this actually that will deal with viruses one of the soil ones is much cheaper than this and that will deal with viruses for you and it's designed for virally high waters so it might be a better option for you to look at but if the virus is bound to a piece of soil or a particle then this filter here will obviously capture that particle and stop the virus going any further if it remains on the particle but not a filter designed for for use in viral waters unfortunately we've got a range of chemicals here and this is certainly not all of them there's a very broad range of chemicals out there used to disinfect water and some are more effective than others and it really depends on cost and a number of other things and whether they whether they get issued and who they get deployed to but one thing that's missing from here one of the main ones the most common three i call them is iodine which we'll talk about at the end but we have chlorine here which is a very common way of disinfecting water we also have chlorine dioxide which is a far more efficient way of disinfecting water and we have neutralizing tablets and neutralizing tablets are designed to go with the chlorine and they make the water more palatable so they effectively take away that swimming pool taste and smell of the actual water which isn't too pleasant when you want to have a lot of water and rehydrate yourself but let's talk about chlorine dioxide first because it really relates back to chlorine and iodine chlorine dioxide tablets are available from a range of companies really that they put their branding on this is life systems and life systems come in this little box they're quite nice actually protects the tablets and we've got up to 30 liters of water that treatable 30 liters of water in this container here and chlorine dioxide is probably the better side of water treatment with chemicals when you're out in the woods and you're carrying tablets like this it's really protozoa that's a problem when you're talking about things like iodine and chlorine and chemical treatments of water iodine not very good for long-term use has adverse effects on the human body and it's not very effective at all at dealing with cryptosporidium it's moderately effective or low to moderate effect on jardia but not particularly good at dealing with cryptosporidium and not good for long-term use either usually comes in droplets or in tablet form you have chlorine as well which is a far more common method of treating water again not particularly good at treating protozoa as sort of low to moderate effects on jardia and not very effective at all at dealing with cryptosporidium iodine and chlorine are both very effective at dealing with bacteria and viruses so this is why i talked about earlier about pairing up something like chlorine or iodine with a water filter not this one really in particular but perhaps the catedin one or some kind of soya filter or an msr filter or optimus filter if you were going to a country where viruses were to be a problem and the waters were very heavily pathogenic with bacteria perhaps you can't boil water because you're not allowed to make a fire in that particular national park or it's a risk at making fire because it's a very hot dry country and very windy then something like this can that you keep in your med kit can really get you out of a situation where you need to disinfect the water and make sure there's no viruses and the bacteria is completely dead as well but if you are going to go with tablets i would recommend chlorine dioxide as a far better way to go its effects against protozoa are far better than iodine and chlorine chlorine dioxide is is far more effective at dealing with jardiya and it's a little bit better at dealing with cryptosporidium i wouldn't say it was a hundred percent because it isn't and um but it's just more effective at dealing with cryptosporidium so you've got a far better better chance really of getting purified water if you're combining methods like this or you've just got this for example but again very good at dealing with bacteria and viruses i would always keep these in my med kit if i was traveling abroad to a country where i suspect about water and unsure about what i was going in for to deal with so we've had a look at a range of technologies and their limitations and what they can do what they can't do and a lot of the products we've looked at today represent almost like a common standard that you find out there on the shelves of the most common products that you get and just having a bit of a basic understanding about what's in the water and what can actually filter it out or neutralize it allows you to then look at filters in a new light i've met people who've gone out and spent a huge amount of money on a katadin pocket and they think it's doing everything they think it's removing herbicides pesticides contaminants and all sorts of things out of the water and then until you talk to them about it they realize that they were wrong and the filter doesn't actually do everything they thought it did and that they just bought it thinking that and um well made that it was doing everything um when really a cheaper filter could have done more than that for them anyway for them but for wilderness expeditions a filter like that is very good obviously but also knowing how to pair products up together if you have med kits on you in your packs you're traveling into the wilderness or you're going abroad to countries you're unfamiliar you know unfamiliar with and what their water quality is like have