Finding Drinkable Water
Sunday, 03 January 2010
Water is an essential of life. We all need at a minimum at least two
liters of water every day to carry on normal body functions and be healthy.
Under many circumstances more water is required to maintain adequate health.
Many facts about water were discussed in the
Necessity of Safe Drinking Water). In this article we will consider where and how to obtain safe
drinking water after disasters or when in the wilderness.
Water supplies may fail because of power outages, pump station failure or
contamination of the supply. Authorities may advise all water should be
boiled if used from the tap. If this order occurs and affects your area, you
should always boil the water in accord with the recommendations of local
authorities ( At least a rolling boil for more than 1 minute.). If you are
advised the water supply is contaminated and must be boiled you should boil
water before use for the following
Should NOT be used for
- Brushing Teeth
- Making Ice Cubes
- Making any drink
- Washing dishes and eating utensils
- Washing hands with soap and clean water (or any body parts exposed to
- Cooking surfaces (cutting boards and counter tops where food may be
placed and so on)
If the water supply fails completely and no other sources are available,
then it is time for plan b, locating other sources of clean drinking water.
Places to find already safe drinking water
Bottled water is a good source, you should have a
three day supply of water
stored in your home according to the needs of your family size and
climate. This water is available immediately without treatment as long as it
hasn't been contaminated by contact with flood water..
A water well (if safe for
drinking) is generally a reliable back up as long as the volume of water
needed does not exceed the capacity of the well. If a water well is exposed
to flood waters then it should not be used until properly tested and
Other sources of water may be provided by government authorities as soon as
possible after a disaster. These sources may require that you bring
containers to collect purified water or they may be provided in already
Other Sources in the Home
These sources are usually available if the water system
supplying your home hasn't been contaminated.
Tapping these sources should supply enough
water for a few days even for a average family after your stored supply of
water has given out. The average hot water heater contains 30 to 50 gallons of
Coping with a complete water supply
If the water supply completely fails
and supplies are low then it's time to find an alternate source of water. These
alternate sources include, streams( not from industrial plant waste water),
lakes and ponds.
Notes of caution
Sea water or salt water should never be used for drinking
unless it is distilled. The salt content of this water is to high and
will only heighten the danger of dehydration and death or serious health
Water in water beds often contains pesticide
additives, do not use for drinking.
The water collected from alternate sources should be considered
contaminated and unfit for any of the uses
mentioned above. This
water must be properly treated to make it safe for sanitary uses. For some of
the dangers of contaminated drinking water see the previous article
Necessity of Clean Water.
of contaminated water is not
difficult and can be done with different methods depending on your
circumstances. Proper treatment will be accomplished by a combination of
methods to produce the best results possible.
Methods of treating contaminated water
Settling/ Cloth filter
Stage 1 Selecting the water source
Select a source of water that can be
accessed as needed and does not contain industrial waste or chemical pollution.
Chemicals and other pollution can render the water unusable, in some cases, even
if distilled. Flood water should be considered to contaminated for drinking
because of industrial and household chemical contamination. Flood waters also
contain raw sewage so it is best to avoid it completely if it's possible. Avoid water that is stagnant or heavily polluted. If you have a
choice choose a source of running water such as a stream or river before a lake,
choose a lake before a pond. Examine your new water source by looking for green
vegetation growing around it, if there is no growing vegetation or even worse
dead vegetation around the water avoid it and continue looking. Examine the area
for the bones of small animals, mice, birds and so on around the area. If these
are present consider it contaminated and select another source. If a dead animal
is lying in a stream, move upstream a good distance to gather water.
Once a supply is selected water can be
gathered directly from it or a hole can be dug about 8 feet away from the supply
and lower than the water level and be allowed to fill with water, this acts as a
natural filter ridding the water of contamination in the air such as radioactive
It is a good idea to locate a backup source of
water in your area now in your area before it is needed. This may save much time and energy
later if you face a catastrophic disaster. This will allow time to find out
about possible pollution and other hazards. If a water source cannot be located,
other methods for detection will be discussed later.
Stage 2 Clearing up visible impurities
The first step in treating your new
water is to filter it through a cloth, coffee filters or other filter.
Alternatively you can let the water set until all the impurities have settled
out then carefully scoop water from the top of the container. After the first
step of clearing the new water of visible impurities has been completed the
water should be clear and look clean. Water that cannot be cleaned to a clear
liquid should not be used. After the clearing process the water can move to the
next stage of treatment.
Stage 3 Killing Microorganisms
The final stage of water treatment is
to kill any disease causing microorganisms that are likely inhabiting the water
by using one of these processes.
Kitchen stove or camp fire method 1
Using a inverted lid in a large pan with a bowl or
cup tied to the lid( or in the bottom with plenty of room so the water doesn't
boil from the dirty water in the pan into the clean water cup or bowl.) clean
water will condense on the lid as the water boils and drip into the clean water
Cloth method method 2
If plenty of water is available you can use this
method but it is very wasteful of water unless the cloth covers the water
container well. Place the water in a pan and heat to boiling, hang a clean cloth
over the pan in the steam that rises. Wring out the cloth regularly into a clean
container to collect the water.
Solar Pit Distilling
A simple solar distiller can be created from a
piece of plastic sheeting or a large garbage bag. a cup or other item to hold
water, a rock and a length of vinyl tubing.
The pit size should allow the plastic bag (split down
the sides to make one sheet) or plastic sheet to fit over it and seal around the
edges. The depth should be about 18" to 30"
Adding vegetation or pouring any contaminated water
into the still to we the soil will increase the water produced. (make sure contaminated water
can't run into the clean water collection cup or doesn't splash into it, this
would contaminate your water. Place the cup in after wetting the soil) If this is your only source of
water dig many stills to increase water production.
Digging a pit around the outside of the solar still,
about 10" from the plastic anchoring will hold unsafe or salt water allowing it
to slowly filter into the pit through the soil and be processed in the still.
How it works
The Solar still is heated by sunlight, this
causes water to evaporate from the soil and any plant matter you have added
under the plastic sheet covering the pit. The plastic sheeting is held in place
all around by rocks and dirt. This water is trapped by the sheet so it
condenses on the bottom and runs to the middle of the sheet because the small
rock is weighting down the sheet in the middle. The water drips into the cup
that is buried in the middle of the pit, directly under the rock. This water can
sipped out through a long piece of tubing (such as aquarium tubing) that is placed from in the bottom of
the cup up to the surface to a convenient sipping height if such is available. Alternatively the cup
could be accessed occasionally to collect water and the sheet, any vegetation or
contaminated water replaced in the pit.
Boiling water for at least one minute (near
sea level) at a
rolling boil should kill all the disease causing organisms. Two to five minutes
may be more effective depending on your elevation (example, boil for 15 minutes
at 10,000 feet above sea level). After boiling the
water will be safe to use, if it isn't contaminated with harmful chemical
pollution. Do not boil the water for long periods of time because this will
reduce the water volume but may not reduce any chemical, heavy metal or other
contamination. In effect this increases the danger of any other contaminating
substance by making it more concentrated. Most water is considered safe to use
after boiling at a rolling boil for over one minute.
Hiking or Survival filters
A number of filters are available that will clean the
water for you to safe drinking levels and remove many contaminates. There
basically two types of filters in this category. They should not be used unless
the filter material is less than 1 micron.
Some units have a container into which the
contaminated water is placed. A filter unit with a straw attached is placed into
the container Others are simply a large straw with a filter built in. As water
is sucked up into the straw by one drinking, the water is filtered through the
filter element rendering it safe to drink. These units are usually less
Pump filters have a hose that can be dropped into the
water supply. The water is then pumped, by using a handle on the unit, through
the filter element and discharged into a container, usually attached to the
bottom of the filter. The advantage of this system is the water is stored and
can be used for drinking or other uses such as preparing drink mixes, washing,
sharing with others and so on..
Iodine or Chlorine based pills or drops can be
purchased and added to the clean water container. Stirred and then allowed to
stand for some time. This method kills most problem causing organisms but is not
completely effective since many variables such as the temperature and amount of
contamination affect the action of any treatment. The pills should contain 5.25
to 6.0 percent sodium hypochlorite as the only active ingredient
Filtering can be followed up by chemical treatment to
Plain (UNSCENTED) Clorox bleach can be used in this
manner to treat water, below is the amount of bleach to add to the water to
treat it. (4 to 6% sodium hypochlorite)
Wait 30 Minutes after treatment before drinking
|Amount of Chlorine
||Drops per Quart
||Drops per Gallon
||Drops per Liter of Clear Water
(If the strength of the bleach is unknown, add ten drops per quart or
liter of filtered and settled water. Double the amount of chlorine for
cloudy, murky or colored water or water that is extremely cold.)
Above are the basic methods of decontaminating water, there are other
very effective devices worth considering such as, one that uses ultraviolet
light and another model uses small batteries and salt to treat even large
volumes of water. Further research can be done in this area.
Protect your treated water supply
Don't allow the water to be contaminated again by
handling with contaminated hands or placing it in contaminated containers.
Remember the lid and any part of any container used in the treatment or for
drinking must also be decontaminated. Cover the water to keep contaminates out
and don't store it for long periods of time.