Are you prepared for a serious water crisis in the days or months ahead?
Producing clean drinking water is the solution to a water crisis. Why? Because contaminated water is dangerous to humans; it sickens populations and many people can die a miserable death from a water born pathogen or poison, that they could have otherwise filtered out, if they had knowledge before hand.
What is going on?
There is a feeling in the country that things are changing for the worse; the government
is deep in debt, politicians are just looking out for themselves, and society as a whole is
beginning to fray. For a variety of reasons it appears that the good old days are winding
down and harder times are coming. A lot of folks look at our high-tech lifestyles and
realize that if critical functions were removed they would be utterly helpless to fend for
themselves. Living without the internet seems unimaginable to many; just think if they
lost electricity, or grocery stores, or running water...
Being Prepared for a Crisis
As the bad news continues to come in there are a lot of folks preparing for a life without
some or all of our modern conveniences. There's a variety of books, blogs, and TV
shows discussing how this might be possible. Of course there are many unknowns
when planning for disaster, such as what happens, how long it lasts, your living situation,
location, and financial circumstances. One thing that you will always need, no matter
what happens, is access to clean water. Even a disaster that only lasts for a few days
could become deadly if it leaves you without water.
DIY emergency water filters
This paper introduces ceramic water filter cartridges, which provide a low-cost, low-tech,
well proven solution that enables clean water to be produced from just about any fresh
What is a ceramic water filter?
The filter consists of
a ceramic shell which usually contains activated
carbon. The ceramic shell has sub-micron sized
pores which filter out small contaminants such as
bacteria and particulates while the carbon inside
treats the water by removing a wide spectrum of
chemicals. Specialized filters that remove particular
chemicals such as fluoride or arsenic can also be
manufactured by using other media in place of the
Low cost water filtration used in third world countries and disaster recovery
These filters are fairly low cost but are often bundled
with fancy containers and big brand names that can
add hundreds of dollars to the price. In reality though, you can make your own water
filter systems at a much lower cost. This has been proven by missionary groups and
NGOs in disaster situations all around the world.
Two pictures are presented below (in lieu of a few more pages of text) to explain how
these systems can be made and used. The picture on the left is made from a couple of
5 gallon buckets with the filter in the middle. Though you can use any type of containers
when building your system, the basic design is almost always the same: A top container
holding the unfiltered water and the filter, and a bottom container to catch the clean
water that drips from the filter spout. The picture on the right shows the parts that make
up an 'emergency kit' which is used to create the system at left. Currently this kit sells
for only $25.
These systems are portable, require no power, are very simple to create and maintain,
and are low cost.
They can be used with just about any freshwater source as has been
proven throughout the world for the last couple of decades by a multitude of refugees.
How much water and how fast?
One of the first questions most people have is "How
much water are these filters good for?" There are two answers for this question. The
filter will remove bacteria and particulates for as long as the ceramic shell is intact. The
pores in the ceramic can get clogged over time, but it is easy to unclog them by using a
slight abrasive to remove the outermost (clogged) layer of shell.
Chemicals are treated by the activated carbon inside which is used up after 6 to 8
months of 'normal' use. 'Normal' assumes 12 to 15 gallons per day from a natural water
source. This implies the carbon will last for 3000 to 4000 gallons. The carbon's lifespan
will be shortened if the water contains a lot of chemicals, such as chlorine. The filters
can be stored indefinitely and used intermittently provided they are dried out well inbetween
A 5 gallon bucket can produce 12 to 15 gallons per day
The amount of clean water a system can produce in a day is another question most
people have. The water flow of a filter dripping out of the spout depends on the water
level in the upper container, so as the water level decreases the flow rate slows. For a
standard 5 gallon bucket the flow rate is 12 to 15 gallons per day assuming the bucket
is refilled a few times. This is plenty of water for drinking and basic needs for a family.
However, one can easily increase the flow rates if larger groups or bartering
applications are needed.
A very simple method to increase flow rates is to place
filters in parallel. For example; if one filter is giving a
flow of 1/2 gallon per hour, placing a second filter in the
container will double the flow rate. (A standard 5 gallon
bucket can fit up to three dome filters). Another
advantage of parallel filters is there is more activated
carbon so you can remove more chemicals. The
downside to this method is that it costs more to
Increase water flow by increasing the pressure on the filter
A second method for increasing water flow is to increase the pressure on the filter.
This can be accomplished by using deep upper containers to provide more water
pressure, or by increasing the air pressure in the container using an air tight seal and a
hand pump. The downside of air pressure is that it increases system costs and also
requires manual labor.
Add a Siphon Tube to produce a "pulling force"
A third method that is low cost is to add a siphon tube to
the output of the filter. This provides a pulling force instead
of a pushing one.
The force is proportional to the length of
the siphon and the vertical distance it is from one end to
the other; the longer the tube the faster the water flows.
a stacked bucket system (where one bucket sits directly on
top of the other one, and the vertical distance is only a foot
or so) the siphon can double the flow compared to a filter
A 'separated bucket' system (shown to the
right) uses a long siphon; this can increase flow rates a lot
more depending on the siphon height. Please note that if
you separate the buckets like this, the bottom one should
stay covered to prevent other contaminants from getting
into the filtered water. This method is probably the best
due to its low cost and low effort required.
Word of caution on flow rate
There is a caveat to increasing flow rates and that is that it decreases the 'contact time'
that the water has with the activated carbon and thus reduces the ability of the carbon to
adsorb some chemicals. The time needed varies with the type of chemical being
adsorbed so unfortunately there is no straightforward answer as to how fast you should
go. The best advice is to filter the water however quickly you have a demand for it.
These water filters can be used in many applications
These filters are adaptable to many applications and configurations. They are used in
rain water systems, well water remediation, and back country living as well as disaster
situations. Besides tens of thousands of refugees, farmers in Uganda, apartment
dwellers in NYC, and water vendors in Central America have all used these filters
One additional benefit of these filters is their potential value as barter items if times do
get really bad. Something fairly inexpensive now could be worth a whole lot more later
on, especially if they're useful.
Ceramic and carbon water filters are excellent devices for families and small groups
Ceramic and carbon water filters
are low cost, do not require electricity to operate, and are
simple to assemble and maintain.
They work on both biological and chemical
contaminants in water sources where many other filter types only work on one or the
In Do It Yourself applications they provide an outstanding value and allow for a
wide degree of customization. They can also provide a form of investment as they
would enable bartering for other valuable goods and services in 'grid down' scenarios.
Homespun Environmental is a small business catering to the DIY 'prepper' market for ceramic water filters. DIY (Doing it yourself) allows for much lower prices and simple water filter systems
that can be customized to particular circumstances and needs. They offer individual
components, affordable, emergency water filter kits, and systems for the outdoor