1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Water Purification

Discussion in 'Bushcraft Chatter' started by Tricia, May 3, 2010.

  1. Harley

    Harley Forager

    Joined:
    Mar 15, 2010
    Messages:
    142
    Likes Received:
    0
    Location:
    London
    ... and ineffective against most common contaminants unfortunately my old bean :)
     
  2. wentworth

    wentworth Settler

    Joined:
    Aug 16, 2004
    Messages:
    573
    Likes Received:
    1
    Location:
    Australia
    boiling is ineffective against, bacteria, viruses and cysts? Aren't these considered the common contaminants?

    I understand that extended boiling times are needed for typhoid spores, but I've noticed a decline in their prevalence in my local waterways of late :)
     
  3. Harley

    Harley Forager

    Joined:
    Mar 15, 2010
    Messages:
    142
    Likes Received:
    0
    Location:
    London
    Typhoid spores?
     
  4. MrEd

    MrEd Native

    Joined:
    Feb 18, 2010
    Messages:
    1,282
    Likes Received:
    274
    Location:
    Surrey/Sussex
    how? which 'common contaminants' are you thinking of?

    filter the large lumps of sticks and dirt out with the bag to make the water 'clear' (i.e. less turbid - which can 'insulate' the organic organisms) then bring to a rolling boil (in a pan) to kill them, it wont sort out heavy metal or 'man made' (fertilisers etc) contaminants though but if you take from a clear flowing source, filter it to remove visual contaminants like dirt and boil it, the risk of getting ill from it will be minimised. I would rather use that method than nothing, and there is nothing to stop you filtering, boiling then dropping a couple of purification tabs in aswell. to remove heavy metals or other chemical contaminants you would have to distill the water after all the boiling filtering stuff.

    what about pasturisation - they basically use heat to kill any pathogens, is that ineffective aswell?

    i just dont get what you mean by boiling not removing common contaminants? are you meaning organic pathogens or toxic chemicals and heavy metals?

    and dont take this as disagreeing/arguing with you, im just interested in others thoughts and knowledge
     
    #84 MrEd, Jun 6, 2010
    Last edited: Jun 6, 2010
  5. Paul_B

    Paul_B Bushcrafter (boy, I've got a lot to say!)

    Joined:
    Jul 14, 2008
    Messages:
    3,725
    Likes Received:
    321
    Location:
    Lancashire
    Anyway whether it filters or treats the water so long as you have "safe" water what's the difference really? I used my drink-safe eliminator last week for the first time and ended up taking it off and just drinking water straight from a suitable stream like I have done for many years. Since I only wildcamp in the hills and mountains I personally think that will be ok. At the end of the day if the water doesn't make you sick then its ok. I did that all week and when I was not able to get a good higher level stream I had water from a campsite tap or cheap bottled water £0.98 for two x 2 litre bottles.

    I do think that in the UK mountain use the requirement for water purification is over played. I also think personal hygiene is underplayed. I mean how clean are your hands when preparing your food? It is all part of the same thing, namely the introduction of harmful elements into your system, you have to consider both ends of the problem. Also how much of a problem is it?
     
  6. Martyn

    Martyn New Member

    Joined:
    Aug 7, 2003
    Messages:
    5,252
    Likes Received:
    31
    Location:
    staffordshire
    It's exceptionally rare to find Typhoid in open water and they can be broken down eventually with extended boiling.
     
    #86 Martyn, Jun 7, 2010
    Last edited: Jun 7, 2010
  7. Martyn

    Martyn New Member

    Joined:
    Aug 7, 2003
    Messages:
    5,252
    Likes Received:
    31
    Location:
    staffordshire
    If you have safe water at the end, none at all, but it's a big if.

    The drinksafe and aquapure traveller filter down to 2µm microns (200nm), which means they physically remove bacteria but not viruses. Beyond that they are relying on brief contact with iodine to "purify" the small stuff. Believing that this is good enough, is an act of faith.

    Traditional methods of treating water with iodine use much higher concentrations and a much longer contact time to purify water - 10 minutes is recommended, 30 minutes if the water is cold. When you squirt water through these iodine impregnated charcoal filters it doesnt get anything like the same dose of iodine or anything like the recommended contact time.

    For reference....

    [​IMG]

    A 2µm (200 nanometer) filter like the drinksafe should not be considered in the same breath as a 0.015µm (15 nanometer) filter like the Lifesaver bottle.

    Again, I have no interest in any of the companies here, I just think it's important we understand the technology behind what we are trusting our lives to. :)
     
    #87 Martyn, Jun 7, 2010
    Last edited: Jun 7, 2010
  8. Harley

    Harley Forager

    Joined:
    Mar 15, 2010
    Messages:
    142
    Likes Received:
    0
    Location:
    London
    I asked out of surprise actually, the bacterium that causes typhoid does not form spores? Assuming for one moment that it did, how on earth would one 'notice a decline' of them in the water?
     
  9. MrEd

    MrEd Native

    Joined:
    Feb 18, 2010
    Messages:
    1,282
    Likes Received:
    274
    Location:
    Surrey/Sussex
    yeah but what about this lol
     
  10. Harley

    Harley Forager

    Joined:
    Mar 15, 2010
    Messages:
    142
    Likes Received:
    0
    Location:
    London
    The mybottle utilises electrokinetic depth filtration to remove viruses and small particles, I'd like to see a Millbank bag do that!
     
  11. MrEd

    MrEd Native

    Joined:
    Feb 18, 2010
    Messages:
    1,282
    Likes Received:
    274
    Location:
    Surrey/Sussex
    the millbank bag is not designed to do that.

    the millbank bag is designed ONLY to reduce the amount of 'turbidity' in the water and remove large items such as grit, silt, small sticks etc etc to give you VISUALLY clear water. you then have to boil it to deal with the organic pathogens.

    the millbank bag is a 2 step system, part 1 filter debris to make water clear, then part 2 is boil (or sterilise with tablets) the resulting water to make it safe to drink.

    a millbank bag IS NOT designed to work as a single filter system, where as the mybottle is.

    I merely suggested it (as an alternative to other methods) as its a time proven, cheap and portable way to provide yourself with clean, safe water.
     
  12. wentworth

    wentworth Settler

    Joined:
    Aug 16, 2004
    Messages:
    573
    Likes Received:
    1
    Location:
    Australia
    I was being facetious. Someone on the forum a few months back argued that boiling was an ineffective water treatment method as there are certain nasties that can survive extended boiling times. Can't remember what. Typhoid, Anthrax, Plutonium... something which is unlikely to be found in the bush.
     
  13. Ray Britton

    Ray Britton Nomad

    Joined:
    Jun 2, 2010
    Messages:
    320
    Likes Received:
    0
    Location:
    Bristol
    Sorry for the delay in my reply.
    I asked about terms used, as there as only two things we tend to do to water to make it potable, and they are: Filtering, and Sterilizing.

    Purifying is an odd term, as items like the 'Trekker travel well' not only don't purify water, but would not work if they did, as they would not be able to add any iodine. It gets even worse when we refer to purifying tablets, as they only add to the water, and don't even get rid of any bits in the first place in the way the travel well does.
     
  14. EdS

    EdS Bushcrafter (boy, I've got a lot to say!)

    Joined:
    Jan 7, 2004
    Messages:
    3,755
    Likes Received:
    25
    Location:
    About as far up the Dales as you can get before th
    Bradford Beck
     
  15. MrEd

    MrEd Native

    Joined:
    Feb 18, 2010
    Messages:
    1,282
    Likes Received:
    274
    Location:
    Surrey/Sussex
    doesnt that have sewrfresh niceness draining into it in places? is it quite heavily culverted with lots of underground sections?
     
  16. Martyn

    Martyn New Member

    Joined:
    Aug 7, 2003
    Messages:
    5,252
    Likes Received:
    31
    Location:
    staffordshire
    I dunno about Bradford Beck, but almost all of the cases in the UK are returning travellers from India and Pakistan. It's carried in poo and is common in places with poor sanitation and uncommon in places with good sanitation and almost unheard of above the farm line.
     
    #96 Martyn, Jun 10, 2010
    Last edited: Jun 10, 2010
  17. EdS

    EdS Bushcrafter (boy, I've got a lot to say!)

    Joined:
    Jan 7, 2004
    Messages:
    3,755
    Likes Received:
    25
    Location:
    About as far up the Dales as you can get before th
  18. MrEd

    MrEd Native

    Joined:
    Feb 18, 2010
    Messages:
    1,282
    Likes Received:
    274
    Location:
    Surrey/Sussex
  19. Harley

    Harley Forager

    Joined:
    Mar 15, 2010
    Messages:
    142
    Likes Received:
    0
    Location:
    London
    'Safe to drink' is a somewhat bold statement MrEd!

    By common contaminants, I mean nitrates/phosphates and suchlike.

    The norm on this type of forum is that someone with the appropriate expertise would have responded by now, however, this debate appears to be floundering?
     
  20. CaptainBeaky

    CaptainBeaky Nomad

    Joined:
    Mar 25, 2009
    Messages:
    309
    Likes Received:
    0
    Location:
    The Green and Pleasant Land
    Might have been Cryptosporidium - tough little sod, that one is :rolleyes:

    Boiling kills everything, and doesn't that long, even for the above. Most common pathogens start turning their metaphorical toes up once you get over 60C, let alone getting to 100C.
     

Share This Page