Clean drinking water is critical to your survival, because without
potable water you will die within a few days. I don't intend to
hammer away on this point, because everyone who visits this blog
generally knows how important it is to have access to clean water,
and this subject has been covered many times from many different
angles. Many of us have several hundred gallons of water stored away
in containers, some more portable than others. Some plan to rely
solely on a Berkey water filtration system to filter surface water
collected from ponds or rain catchment barrels. While the Berkey
filters are excellent and water storage is a must, having these will
not be good enough in a prolonged grid-down scenario. Your water
storage may run dry, and your Berkey filters have a limited lifetime
and may not be able to handle long-term filtering.
The Lord handed us a pristine planet, and though we may have
polluted much of the water we have been entrusted with, He has
given us the materials and intelligence necessary to purify our
water. Most of the modern world relies on municipal water
treatment facilities to provide them with clean water. Water flows
from faucets and toilets flush with the flip of a lever as surely
as the sun rises and sets. By paying the water company every month
we are guaranteed an almost unlimited supply of clean water. Most
of the time the public shows no appreciation for the system that
delivers the water or knowledge of the process by which it is
treated and delivered, but most everyone expects to be provided
with water as though it were a birthright. The public generally
does not question the quality or safety of their water while the
nameless, faceless technicians at the utility company work their
"magic", and we generally put our faith in them to deliver.
However, some of that faith has been shown to be eroding over the
last few decades as more people have been relying increasingly on
water filtration systems and bottled spring water.
I hope that the reader will understand that there is no magic
taking place at water treatment plants, and that individuals are
capable of treating contaminated water in their own home in much
the same way as it is done at a water treatment plant. I should
note that I do not advise anyone to drink water that may be
unsafe, or to treat unsafe water for drinking. The materials and
methods I describe may be hazardous if proper care and proper
safety equipment are not used. Because I have no control over the
quality of your source water, or the procedures you employ, I can
not make guarantees and will take no responsibility for injury or
illness that may result from this information. I am not providing
explicit instruction or advice. In an extended grid-down scenario,
however, almost every activity will come with a heightened degree
of risk, and at that time only you will be responsible for making
risk assessments concerning water availability and water quality.
I can say that I have personally used the method I am presenting
here to treat and drink small amounts of water from a canal in the
downtown area of a large southwestern city. The water I drank did
not pass through a water filtration system as I advise in the
final step below to insure absolute safety. I felt there would be
no point in using the Berkey as part of the test because the
Berkey is quite capable of handling contaminated water without
prior filtering or treatment. My method is intended for a maximum
production of just over 12 gallons of water per hour. This volume
of water is more than suitable for bathing and cooking, and
somewhat suitable for drinking. However, the final step for
absolute safety would be a pass through a Berkey or similar
filtration system or by boiling.
Required Materials
This is a list of materials you will need to set up your water
treatment system and should not cost more that $200. [In 2014 USD]
Aluminum Sulphate - Known as Alum, a 5lb. tub can be
purchased at any pool supply store for $15. This is a type of
flocculent which will make suspended solids in cloudy or turbid
water stick together and sink to the bottom of the container.
See flocculation in action in this video.
Calcium Hypochlorite, commercially known as pool shock. A one
pound bag costs $5 or less.
Five gallon white food grade buckets, at least two.
Five gallon colored non-food grade buckets, such as Homer bucket from
Home Depot, at least three.
Sturdy glass bottles with ground glass stoppers (laboratory
grade glass) to safely store the calcium hypochlorite. These can
be expensive, but Amazon
has some very reasonably priced bottles.
Basic pool chlorine/PH test kit. Buy additional large bottles
of testing solution.
Fifty-five gallon plastic drums. You should already have several of
these in your backyard.
Cloth filter. I use a Singed Polyester Felt Filter Media
Fabric Sheet for use in aquariums.
Hydraid Biosand
Filter.
Pool
filter sand.
Aquarium gravel. Ten pounds with smooth rounded edges
approximately 1/8 of an inch in diameter to 1/4 of an inch in
diameter
Aquarium gravel. Ten pounds with smooth rounded edges
approximately 1/2 of an inch in diameter to 3/4 of an inch in
diameter.
One gallon plastic jugs. Two or three will be enough, and they
should be clean. Do not use milk jugs.
Measuring spoons. This set should be dedicated for water
purification and not used for cooking.
Tuna Fish can, 4.8 ounce to 5 ounce. Can should be cleaned
thoroughly.
Twelve ounce jar or can with lid removed.
Five pounds of non-galvanized iron nails, three to four inches
long. The rustier the better, and if they are new out of the
box, make sure they are wiped clean, and completely free of
grease. This is only necessary if you are concerned about
mitigating the arsenic in your source water.
Activated carbon or charcoal pellets. These can be purchased
at Wal-Mart
in the aquarium section or at any aquarium store.
Some important notes on materials:
Pool Shock
Calcium
Hypochlorite is a dry form of bleach with chemical
compound Ca(CIO)2 better known as "pool shock" and can be
purchased at Walmart, Home Depot, or any pool supply store.
Avoid pool shock with clarifiers or anti-foaming agents. A
concentrations of 78% or higher is preferred, but do not buy
anything lower than 65% Ca(CIO)2.
This powdered form of chlorine is superior to liquid bleach
because it has a very long shelf life, very compact and is
highly portable. Calcium Hypochlorite is very caustic to the
skin. The fumes can burn eyes, lungs, nasal passages and
sinuses; seep into your food storage; ruin the biolayer in
your biosand filter; and it will rust every tool in the shed
if not stored properly. You must wear chemical resistant
gloves and eye protection and work in a ventilated area when
handling this stuff. I always handle Calcium Hypochlorite on
the back patio, and only if there is no breeze. You do not
want to be down wind if there is a breeze.
Pool shock must be stored in glass labware with ground glass
stoppers only. Do not use mason jars, Dutch beer bottles with
ceramic stoppers and rubber gaskets, or corked wine bottles.
Over time, the chlorine gas will eat through rubber gaskets,
plastic, cork, and even metal. So, do not take a shortcut on
this because chlorine gas is no laughing matter.
For safety reasons, pool shock must be kept dry like regular
dry pool chlorine. Refer to the safety guidelines on the
packaging.
I keep my pool shock in reagent bottles, and I carefully pack
the sealed bottles inside Home Depot buckets with bubble wrap
to cushion the glass. I then seal the bucket tightly with the
bucket lid. The bottles and buckets are clearly labeled with
information about the contents, with warnings like "keep dry",
"caustic", and "fragile".
You might be thinking at this point, "Why take the risk? Why
not just keep a few bottles of Clorox around instead of this
dangerous dry chlorine?" Understand that liquid bleach has a
short shelf life. It loses its efficacy at an unacceptable
rate, and within a year or two your bleach will be useless.
You cannot rely on weak bleach to disinfect your water. With
unknown potency, you will be playing a guessing game with
ratios, and over time you will effectively have no bleach at
all. Consider the following:
Currently, a one pound bag of pool shock costs about $5.00
or less.
This one pound bag of pool shock has an unlimited shelf
life, if it is stored properly.
A one pound bag of pool shock will make 128 gallons of
stock chlorine solution, the equivalent of 128 gallons of
bleach.
This 128 gallons of stock chlorine solution will disinfect
12,800 gallons of contaminated water.
If you factor in weight, cost, and value, there is no other
item in your preps that can come close to a bag of pool
shock. Twenty pounds of pool shock stored at your retreat
translates into 256,000 gallons of clean water. Should you
ever need to bug-out, one or two pounds would be very easy
to pack.
Hydraid Biosand Filter
The filter
The Hydraid biosand filter stands two and a half feet
high. It is roughly one and a half feet wide at the top
with a taper leading down to a smaller diameter base.
Unlike traditional concrete filters, which are often
constructed on site, the Hydraid is plastic and very light
weight when empty. The Hydraid looks a lot like a small
round plastic recycle bin with a PVC pipe running up the
length on the outside. For those unfamiliar with biosand
filters, please look at this video.
The design of the filter is brilliantly simple in one
sense because it looks to be just a plastic trashcan
filled with four inches of rocks on the bottom, a few feet
of sand on top and a PVC pipe running out of the bottom
and up the side. The complexity of the design is not so
apparent. The biosand filter works several ways:
The first phase is biological predation where
micro-organisms feed on dangerous pathogens. The top
surface of the sand at the top of the filter perpetually
sits below several inches of water, and develops a
biological layer of beneficial organisms which consume
and remove parasites and pathogens up to 99.8%.
The second phase is mechanical filtration. The sand
acts as a mechanical filter, physically trapping debris
and pathogens.
The third phase of filtration is adsorption. The
filter media emits an electrical charge of sorts and
pulls the remaining debris to it like a magnet.
From this point, the water slowly filters down through
the last few feet of sand which is devoid of light, food
and oxygen, killing off any remaining organic pollutants
and pathogens.
It is important that no chlorinated water, tap water,
iodine, or chlorine gas ever come into contact with the
biolayer because the disinfectant will kill off the
beneficial organisms, thus destroying the biolayer. It is
also important to place the filter indoors and in an area
where it will not be disturbed. If the filter is placed in
a high traffic area and it gets bumped or rocked, the
biolayer may be damaged.
Contaminated water should always be poured onto the
diffuser plate where it will drip gently down onto the
biolayer. Water should never be poured directly onto the
biolayer, as that too will damage it. By being consistent
with your source water, the biolayer will develop
organisms specifically catered to treat water from that
source. A biolayer formed from canal water may not be so
effective against pathogens from harvested rain water.
According to the Hydraid brochure, the filter is capable
of producing 12.4 gallons per hour with intermittent use.
This amount of water serves the daily needs of eight to
ten people. If you consider that one person requires one
gallon of water per day just to survive, 12.4 gallons per
hour would be a luxury for you and your family in a long
term survival scenario.
Triple Quest Company and ordering information
Before ordering, you must understand the intended
application for this filter. The filter needs to be set up
correctly with the filtration media. It needs to be primed
for several weeks to let a biolayer develop, and it needs
to be used and maintained on a consistent basis. None of
this is especially difficult, but it does require some
commitment, unlike ceramic or carbon filters which are
more "plug and play". In an extended grid-down scenario,
as in months or years, the biosand filter would be a
perfect choice. The biosand filter is not a good choice
for those prepping for short term events like hurricanes,
floods, or temporary civil unrest. Someone living in a
remote area without well water but access to a stream
or pond, could definitely rely on one or two Hydraid
filters. A Hydraid would not be suitable for a vacation
cabin because it would not be used and maintained with
regularity.
From what I understand, the Hydraid is not intended for
use in this country, and it is not marketed as a retail
item. Triple Quest manufactures these filters for Non
Governmental Organizations (NGO's) like UNICEF who provide
aid to families in developing countries. Triple Quest is
geared for handling orders by the pallet load to be
shipped overseas. Triple Quest is not accustomed to filling
orders of one or two units for domestic use, so please
take this into consideration when ordering your filter. By
doing business with Triple Quest, you are supporting their
humanitarian operations. Whether they would admit to
it or not, they are doing God's work by providing, free of
charge to the poorest of the poor, a device to filter
horribly contaminated water.
Though research has shown the Hydraid to be incredibly
effective against biological contaminants, parasites, and
pathogens, Triple Quest will not recommend it for general
use in this country. The filter is intended for use by
people in developing countries living in squalid
conditions. It may be that another reason Triple Quest
cannot promote these filters for the American market is
because they have no control over the water source that
the user may attempt to filter with their product. Should
the user not follow the installation and maintenance
instructions properly or try passing water contaminated
with diesel fuel or chlorinated tap water through the
filter, the end result would reflect poorly on the
product and could leave the company exposed to endless
litigation. This is just my guess as to why these filters
are not marketed to the public.
To order a Hydraid BioSand filter, contact Triple Quest
at (616) 254-4222.
Sourcing local filtration media
When you place your order for a Hydraid
filter, do your
wallet a favor and order the filter only. If
you order the
filtration media, you will have to pay
shipping on 106
pounds of sand and rock, all of which can be
purchased at
a swimming pool store and aquarium supply
store for a lot
less. When you place your order, ask how
many pounds of
each type of media you will need. By
purchasing just the
filter, which includes the plastic body,
lid, diffuser
plate, and outlet pipe, you can probably
spend about $70.00, including shipping. If you opt to pay for the load
of
sand and rocks, the cost will be at least
twice that
amount. It would make more sense to spend
that money on an
additional filter to give to a family member
or friend.
Inferior designs and short circuits
Do not attempt to rig a common trash can with a PVC
standpipe for use as a biosand filter. Most trash cans are
made out of low density polyethylene and will easily flex
and bow out at the sides, creating a short circuit of
sorts where the water on top bypasses the sand filter
entirely, running down the sides to the bottom where it
will enter the outlet tube. The Hydraid is made from a
higher density polyethylene and is rigid enough to prevent
a short circuit. Likewise, never build a biosand filter
with the standpipe tube running up the inside of the
filter. This will also create a short circuit, as the water
on top will follow the outer wall of the PVC pipe right
down to the bottom, bypassing the filtration media. I have
seen several how-to videos on how to construct one of
these dangerously designed filters on Youtube, many of
which are too painful to watch. This video
demonstrates the wrong way to build a
biosand filter.
Because the consequences of drinking contaminated water
are so severe, stick with the design that is tried and
true.
Sand
The best filtration media for the biosand filter is pool
filter sand. This sand can be found at Home Depot and swimming
pool supply stores. Do not use masonry sand, play sand, or
beach sand. The size of a coarse grain of sand like what you
would find in a sandbox is measured in fractions of a
millimeter. The size of a fine grain of sand, like pool filter
sand, is so small it is measured in microns. The organisms we
are trying to keep from entering our bodies are in the micron
range and will easily pass right through coarse sand. The
size of the grains in a bag of pool sand are very consistent,
ranging between 10-40 microns.
Activated Carbon (Charcoal)
If you do not have a Berkey system, you can make a carbon
filter with activated charcoal/carbon pellets from Walmart or
an aquarium store packed into a 2 liter plastic bottle with
the bottom cut out. This carbon filter is in no way as capable
as a Berkey, but it will remove excess chlorine, heavy metals,
and fluoride from your water, making it safer and giving it a
much cleaner taste. These pellets are relatively cheap and
easy to store in bulk. Never filter your water with charcoal
intended for BBQ grills, whether it was treated with lighter
fluid or not. Grilling charcoal is not activated, so it makes
for a poor filter. This type of charcoal is also very good at
absorbing airborne contaminants right through its paper bag as
it sits on the shelf at the hardware store for months on end.
The charcoal will absorb nearby pesticides from the garden
section and petrochemicals from the quick light charcoal bags
sitting a few feet away.
Before beginning, understand that this process is not guaranteed
to remove pesticides, heavy metals, or petrochemicals, unless a
Berkey filter is used in the final step. It is important to find
the cleanest water source possible. However, do not collect chlorinated
water or add chlorine or any other disinfectants on the front end
of this process. Chlorine and other chemicals will damage the
biolayer of the filter. Once your biosand filter is set up and
primed, you can begin. You can see the proper set up in this video.
Collect surface water in colored 5 gallon bucket. Filtered
water should never be poured into a colored bucket, and raw
untreated water should never come in contact with a white food
grade bucket.
Cover the bucket and let the water sit undisturbed for a
day.
Sediment should have settled to the bottom. Place a cloth or a
Singed Polyester Felt Filter Media Fabric Sheet over another
colored bucket and carefully pour the clear water into the
bucket, making sure not to let any sediment enter the second
bucket. Clean out first bucket and rinse the Singed Polyester
Felt Filter Media Fabric Sheet.
Place a clean empty white bucket underneath the vinyl outlet
tube of the Hydraid biosand filter.
Remove the lid from the top of the filter and gently pour the
water onto the diffuser plate. Be very careful that not even a
drop of the contaminated water drips down into the clean white
bucket sitting on the floor. Pour the water slowly and
carefully. Place the cover back on top. Filtered water should
begin flowing into the white bucket as the water in the filter
finds equilibrium.
Store the filtered water in a clean 55 gallon drum designed
specifically for water storage.
Repeat the filtration process until the drum is nearly full.
Leave a little room for your chlorine solution.
Put on eye protection and chemical resistant gloves.
Pour a half gallon of water into a one gallon jug. Add 1/8 of
an ounce (about 1/4 teaspoon) of pool shock to the jug. Cap the
jug and gently shake or swirl the contents until they are
dissolved. Fill the jug with water until it is about full.
Pour one half gallon of the chlorine stock solution into the
55 gallon drum and let it sit for a day.
Collect a small amount of treated water from the drum and run
a chlorine test with your pool test kit. A chlorine reading
under 0.2 parts per million (ppm) is too low, and is not
considered safe according to the EPA. A higher chlorine reading
around 3.5 to 4.0 will make for very unpleasant tasting water
and can cause health problems over time, but you can be assured
that all pathogens are dead. If your water has a chlorine level
between 0.2 and 4.0 ppm, it is safe to bathe with, wash clothes,
and probably safe enough to drink.
For additional peace of mind and for improved taste, it would
be a good idea to run your drinking water through a Berkey or
other charcoal filter one or more times to remove all chlorine
and any residual contaminants. The pre-filtering and slow sand
filtering with the Hydraid will no doubt greatly extend the life
of your Berkey filters.
If you wish to bypass the biosand filter altogether and run all of
your water through a Berkey or other carbon filter, I suggest the
use of Alum in addition to performing steps 1 through 3 above . The
Alum acts as a flocculent, which pulls together all of the
undissolved solids floating around in the water, most of which are
too tiny to be seen. I have not been able to find any information
regarding Alum and potential interference with the biolayer of the
filter, so I never flocculate water before running it through the
biosand filter. I imagine that the Alum would be indiscriminate, and
remove many of the beneficial micro-organisms from the water as well
as the dangerous pathogens.
Collect surface water in colored 5 gallon bucket.
Cover the bucket and let the water sit undisturbed for a day.
Sediment should have settled to the bottom. Place a cloth
filter or Singed Polyester Felt Filter Media Fabric Sheet over
another colored bucket and carefully pour the clear water into
the bucket, making sure not to let any sediment enter the second
bucket. Clean out first bucket and rinse the Singed Polyester
Felt Filter Media Fabric Sheet.
Fill the empty tuna can with Alum, then scoop the Alum into
an empty water jug. Fill the jug about half way with water, cap
it and gently shake for a few seconds.
Pour the alum solution into the bucket of water, cover and
let sit for a day. Rinse out the jug that contained the Alum
solution.
After 24 hours, the water should be very clear and clean
looking, and a fair amount of sludge and scum will be resting on
the bottom of the bucket. Again, carefully pour the clear water
into a clean bucket, making sure not to let any sediment enter
the second bucket. Clean out first bucket.
Add 16 drops of your chlorine stock solution, mix well, cover
and let sit for a few hours. See step 9 above for instructions
on making chlorine stock solution.
This water is now ready to be poured into your Berkey or
homemade carbon filter.
If you wish to treat more than five gallons of water at one time,
refer to the following ratios to create a flocculent solution.
Five gallons of turbid (cloudy) water requires one half gallon
of Alum solution made up of 5 ounces (empty tuna can full) of
Alum powder mixed with one half gallon of water.
Ten gallons of turbid water requires one gallon of Alum
solution made up of 10 ounces of Alum powder mixed with one
gallon of water.
Twenty five gallons of turbid water requires two and a half
gallons of solution made up of 25 ounces of Alum powder mixed
with two and a half gallons of water.
Fifty gallons of turbid water requires five gallons of
solution made up of 50 ounces of Alum powder mixed with five
gallons of water.
One gallon of chlorine stock solution will treat one hundred gallons of biologically unsafe water.
One quarter teaspoon (1/8 of an ounce) of pool shock added to one
gallon of water will make enough stock chlorine solution to treat 100
gallons of water.
Twelve to sixteen drops of stock chlorine solution will treat one
gallon of water. Depending on the concentration of Ca(CIO)2 in the pool
shock you use to make the solution, it may require more or less. Test
chlorine levels with your pool test kit.
The process described in detail above can be broken down into four steps:
Screening and pre-sedimentation.
Coagulation, flocculation, and sedimentation.
Filtration.
Disinfection.
These are the same basic four steps that your municiple tap water is
subjected to before it reaches your faucet. The chemicals, agents, and
methods presented here are very similar to those used by water treatment
facilities.
If you suspect that you have arsenic in your source water, there is a
simple modification that can be made to a biosand filter. I tacked this
on the end because most people will not have to worry about this
problem. Parts of Southern California, Arizona, North Dakota, South
Dakota, Minnesota, Maine, South Texas, North Texas, Massachusetts, and
Montana have concentrations of 50 or more micrograms per liter in their ground water.
Some arsenic is naturally occurring and enters the water supply
through runoff of eroded natural deposits. Runoff from farms and waste from glass
and electronics production are other sources of arsenic. The modification
I made to my Hydraid is a simple one, and it involves nothing more than
a few pounds of non galvanized rusty iron nails placed on top of the
diffuser plate of the biosand filter.
Without getting too technical, arsenic in the water is attracted to
the iron oxide in the rust, which then flakes off and becomes trapped in
the sand, never making it more than an inch or two into the filter.
Without the rust, arsenic would pass through the sand unobstructed.
I hope that I have demystified the process for treating water and
that there is no magic taking place at water treatment plants. All of
these steps to treat water, except for chlorination, are just an
accelerated simulation of the natural process of filtration and
sedimentation. With these basic materials and instructions, anyone can
begin learning how to treat contaminated water. By familiarizing
yourself with the Hydraid biosand filter, you will learn the mechanics
of how these filters work, and you will carry this knowledge with you
wherever you go, whatever the circumstances. At some point, if the need
should arise, you may even be able to construct a large capacity biosand
filter out of concrete or masonry block, with scavenged materials. Now
is the time to learn and perfect this skill.