Water Purification in Bushcraft
Water collection is something you will need to do at some
stage while on a bushcraft week or weekend, Look for a suitable source, a
flowing water source is generally more preferable than a static one, but no
matter where you take your water from, be aware of sewage and visible
contaminants at source.
Provided your source looks clean and is suitable for
collection, i.e. easily accessible and risk free, you have various contaminants
which you will need to remove before drinking, If ground water is not workable,
think of other methods of water collection, such as vapour collection from
plants using a plastic bag or a condensation pit. The main hazard from all
water comes in 5 main categories:
1.
Water Clarity – Floating particles, sediment, debris and decomposing
matter.
2.
Parasites – Waterborne organisms that rely on other organisms to
survive or feed on, such as worms or protozoa, which can carry diseases harmful
to humans
3.
Bacteria – Single celled organisms which cause disease. Bacteria
are generally classified as either helpful or harmful. Bacteria are found
everywhere, and appear on every surface and every part of the human body. The
helpful bacteria are commonly found in yogurt and cheeses, and are good for digestion.
The other types are harmful bacteria, those that you may be more familiar with
are:
A) Streptococcus Progenies responsible for skin
infections and sore throats etc
B) E-Coli responsible for gastrointestinal diseases
C) Vibro Cholerae responsible for Cholera
D) Enteritis Salmonella responsible for food poisoning
E) Salmonella Typhi responsible for the deadly Typhoid
4.
Viruses – Viruses cause disease in organisms that they infect, they
are microscopic and are unable to be filtered out of water, and Viruses are
measured in Billions of micrometers (nano) as opposed to protozoa which are
measured in thousands of micrometers. (A micrometer is a millionth [10(-6)]
of a meter.)
Viruses are quite often responsible for Diarrhoea
transmitted mainly by water. Hepatitis A and Polio are also among the more
serious viruses that can be transmitted in faecal water, which is why if you
travel to foreign countries that it is very important to know that any salads
or vegetables have been washed with pure clean sterile water prior to
consumption.
5.
Chemical pollutants – Pesticides or heavy metals are often the
result of agriculture, chemical pollution or mining. Dead fish and vegetation are clear signs of serious chemical pollution.
Chemical pollution is often not as obvious so you need to be careful; the signs
are much more subtle. With a little bit of pre-trip research we can judge if we
are visiting an area where chemical pollutants may be an issue (for example
will you be near mining or sewage, or
is there a lot of agriculture nearby which could pollute nearby water sources.
How to Deal with Water Contaminants
It is unusual to
have to deal with all 5 types of contaminants, but as a rule you should remove
any particles by filtering first then follow up by boiling. Consider using a
water purification pump that combines filtration and chemical treatment.
Remember the
first basic principles, keep things as clear as possible, the important points
you need to remember are as follows:
1.Coarse
filtration will remove turbidity
2.Microfiltration
will remove the larger pathogenic organisms (protozoa and some bacteria)
3.Boiling will
kill all pathogenic organisms (at any level)
4.Certain types
of filtration (activated carbon) can remove some chemical pollutants
5.Some chemical
treatments (chlorine, iodine) will kill many pathogenic organisms (in
particular bacteria and viruses), while other treatments (chlorine dioxide)
will deactivate all of them
Therefore we can
deduce a combination of filtration and a suitable chemical treatment or boiling
will deal with any or all of the specific contaminants. If you understand these
fundamental principles, then you can start to make wise, informed and rational
decisions in your scenario.
The presence of
waterborne pathogens is often associated with the presence of humans and
domesticated animals and often a result of bad sanitary practice. (excrement
contaminating the water). In many places where there has been little or no
human activity and no livestock or pack animals, then the water can be free of
pathogenic organisms and safe to drink. But remember we can’t know for sure
without testing the water.
If locals drink
the water, remember that there immune system is used to the surrounding conditions,
Pre-trip research will also help you determine which waterborne pathogens are
possible, likely or endemic in the country or area you are travelling. This
type of research is very important and can help with determining which
inoculations, if any, you require before a trip.
For a reliable Chemical filtration system visit ; http://www.pre-mac.com/PWP_MWP.HTM
