Tips for building a homestead cistern, including the cost and types of cisterns available.
Whether your well has just gone dry and you need a
new (and preferably low-cost) source of water . . . or that
sprig you’ve been drawing from doesn’t always produce as
much as you (or your animals) would like . . . or you’ve
grown tired of the taste of city water . . . you’ll want to
see what Penny and Lou Kujawinski (authors of the following
article) have to say about their homestead cistern and how they
collect and store rainwater for homestead use.
Have you ever looked at a pretty piece of land but
hesitated to buy the property because it lacked water?
(Quite often, an otherwise-attractive parcel of land that
has no well, pond, stream, or spring will be priced so low
that you may be tempted to buy the tract anyway.) Lack of
ground water is a common problem . . . one that the folks
in our part of Missouri — early settlers and
present-day farmers alike — have learned to get around
by the use of something known as a rainwater
cistern.
A rainwater cistern is — as the name
implies — simply a setup for collecting rainwater
(usually the precipitation that falls on your home’s or
barn’s roof) and storing it until it’s needed in a (usually
underground) concrete or masonry tank. Cisterns are ideal
for farms and homesteads situated on waterless land, or for
areas where the natural ground water is too
hard — contains too many dissolved minerals — to
drink, use for washing hair, etc. (Fact is, some of the
people hereabouts who have good springs on their
property have gone ahead and installed cisterns anyway,
just because they prefer the taste of rainwater.)
We didn’t feel out of place, then — upon moving to our
present home — when we designed and constructed a
simple rainwater-collection system large enough to supply
all our needs for water. And — despite the limitations
inherent in such a system — we’ve never regretted
having gone this route. (It sure beats spending upwards of
$1,000 to drill a well for water that may or may
not be there!) Quite possibly, a cistern could be the
answer to your water-supply problems, too.
How to Know Whether a Cistern is “Right” for You
Cisterns won’t work for everybody. In fact, for such a
setup to be at all useful, the following conditions must
apply:
[1] You must live in an area that gets plenty of rain. As a
general rule, you can figure that if crops can be grown
without irrigation where you live, there’ll probably be
enough precipitation to meet your water needs. (In times of
drought, you can do what we do: Have water hauled in, at a
cost of about $10 per 1,000 gallons.)
[2] The rainwater collection surface — usually a house
or barn roof — should not be located near (or downwind
of) any source of pollution (such as a major highway,
fields or orchards where spraying occurs, or factory
smokestacks).
[3] Your water needs must not be excessive. (For those of
us who prefer a dry toilet to the kind that wastes up to
seven gallons of H20 with every flush, this requirement
shouldn’t pose much of a problem.) Of course, if you’re
thinking of building a cistern to supplement your
present well, spring, etc., this factor becomes less
important. The main thing to remember is that if — like
the average American family — you use 100 gallons of
water per person per day . . . you’re either going to have
to cut down on that consumption, or build a cistern large
enough to fulfill your needs (which — depending on the
amount and frequency of rainfall in your area — could
mean a tank of 5,000 to 10,000 gallons’ capacity, or
larger).
Underground or Aboveground Cisterns?
Cisterns can be built above- or below-ground. The advantage
of an aboveground installation is that the weight of the
water itself (as long as the storage tank is above
faucet-level) can be harnessed to pressurize your home’s
waterlines . . . whereas with an underground cistern, it’s
necessary to pump the water from the storage vessel to the
house. On the other hand, with an underground cistern [1]
the water remains cooler in the summer (resulting in less
evaporative loss), and [2] there’s no danger of the liquid
freezing in winter. We chose to build our cistern
underground for these reasons.
How Much Will a Cistern Cost?
Cisterns can vary widely in cost, depending on how fancy
you want to get and how much of the installation you do
yourself. Our system — which centers around a 13′-deep,
1,100-gallon storage tank built of fieldstone and
mortar — set us back a total of about $100 . . . for
everything, including gutters, cement, pipes, and an
old-style manual pitcher pump. By contrast, some neighbors
of ours spent approximately $1,000 to have a contractor
install a pre-cast concrete cistern with an electric pump
and an automatic chlorinator. As you can see, then, exactly
how much you spend on a cistern installation depends
largely on what you have more of: time or money.
The Cistern’s Components
All cistern setups can be divided into three components:
[1] the water collection system (roof, gutter, and
downspout), [2] the filter, and [3] the water storage
vessel (or cistern).
A very important thing to keep in mind about your cistern’s
water collector is that the collection surface (the house
or barn roof, in most cases) must be free of any
material(s) which might pollute the water it catches. (A
painted surface isn’t suitable, since chips of the
protective coating will inevitably wash down into the
storage tank.)
To aid in keeping their collected water clean, most cistern
owners install a “shut-off” (or short length of movable
pipe) in their systems’ downspouts. Then, during the first
few minutes of a rain — when all the soot, bird
droppings, etc., that have accumulated on the roof’s
surface begin to wash away — the runoff can be diverted
away from the cistern. (This tainted water can be shunted
to the garden or used in any way you’d use “gray water”.)
Shortly afterwards — when it has rained a few minutes
and the water flowing through the downspout appears clear
and clean — the shut-off can be switched back to direct
the remaining portion of the shower or storm into the
cistern.
The filter mentioned above is usually nothing more than a
concrete enclosure (see diagram) that’s divided into two
sections by a partition reaching two-thirds of the way to
the chamber’s top. One of the two sections is left empty,
while the other is layered full of filtering material(s) .
. . usually gravel, fine sand, and/or activated charcoal.
The idea is that as water flows from the downspout to the
first (i.e., empty) section of the “filter box”, bits of
leaves, dirt, etc., will settle out . . . then — as the
collected liquid spills over the partition and begins to
percolate down through the layers of filtering
material — smaller impurities also will be removed. A
screen prevents any remaining debris from flowing into the
supply line that connects the filter box with the cistern.
The cistern itself should be made of concrete, stone, or
some other non-corroding, non-contaminating material (wood
and metal are not recommended). In addition, the
storage tank must be [1] watertight, [2] effectively sealed
against outside contamination, and [3] fitted with some
type of overflow opening. For optimal protection against
contamination, the cistern’s hatch door should fit tightly,
the overflow should be screened to prevent small animals
from entering, and care should be taken to locate
outhouses, septic tanks, cattle run-off areas, etc., at
least 100 feet away (preferably downhill ) from
the tank. (Note: Your cistern most definitely should
have a hatch door on its top, since the vessel’s floor
will need to be cleaned every couple of years or
so.)
Although we don’t necessarily recommend the use of such
poisons, chlorine and other chemical disinfectants can be
added to your cistern — either manually or by means of
an automatic dispenser — from time to time to ensure
the sterility of your water supply. [EDITOR’S NOTE:
Some commercially available water disinfection units rely
on heat or ultraviolet light — rather than
chemicals — to get the job done. Look in the Yellow
Pages of your phone book under “Water Purification
Equipment” or “Water Supply Systems”.] You may want to
consult the local health authorities — or your county
agricultural extension office — about whether or not
you should disinfect your cistern’s water.
The Cistern Pump
Unless your cistern is situated above faucet-level, you’ll
need a pump to force the water out of it. Here — as
with wells — you can choose from any number of kinds of
devices (some expensive, some not) to do the job. For
simplicity and low cost, we installed a hand-operated
piston pump atop our cistern . . . and it works quite well.
If you decide to go this route, remember that a piston pump
can only draw water a maximum of 25 feet from the source.
(Which means you should build your cistern close to the
house if you intend to use an indoor hand pump to empty
it.)
The Kujawinski Cistern System
Our own system — though it works well enough for our
needs — bears the marks of a first-time
do-it-yourselfer and could stand some upgrading in certain
areas. For instance, our water collection surface (a 24 foot by
24 foot cabin roof) should really be somewhat bigger to furnish
us with a truly adequate water supply. (As it is, it takes
a 5″ rainfall to bring our cistern up to the 600-gallon
mark.) Then too, the underground tank could’ve been a
little larger . . . but digging through the hardpan clay we
have in this area is no easy chore.
I might add that although fieldstone is inexpensive and
abundant, it was not the best possible choice of
construction material for our holding tank, since [1] the
stones in our area are of odd sizes and shapes (rarely
square or flat) and [2] the process of fitting each rock in
place individually was excruciatingly slow and fatiguing. A
small additional outlay for the extra cement and gravel
that would’ve been necessary to do the whole job in
concrete would have made life a lot easier . . . and
construction a great deal speedier. (The cistern’s
reinforced-concrete top was certainly easy enough to
fabricate.) Now that the job is finished, though, I suppose
our only real regret is that the beauty of the cistern’s
stone walls cannot be seen from above.
One part of our system that we’re particularly pleased with
(especially considering that its dimensions were arrived at
mostly by guesswork) is the water filter (a trapezoidal
concrete box divided into a 2 foot by 3 foot by 1 foot-deep “main
section” and a smaller, triangular section with 18 inch-long
sides). So far, we haven’t had a chance to try sand,
charcoal, and gravel in combination . . . instead, we’ve
had to rely just upon pea gravel and metal screening as
filtering agents. (The screening is installed below the
gravel as well as atop the filter box’s partition wall.)
Nonetheless, we’re quite happy with the clean water that
our filter produces.
Do Some Digging Before Building a Cistern
If I had just one piece of advice to give to someone who’s
interested in installing a rainwater cistern, it’d be this:
Do your homework before you begin. Check with your
state health department and the state department of
agriculture for literature on the subject of cisterns and
water systems. Also, talk to your county agent . . . he may
be able to suggest (or even give you) helpful bulletins,
reprints, etc. A trip to the library could also prove
beneficial.
Unfortunately, you won’t find detailed discussions of
cisterns in many of the popular books on homesteading. Two
guides that do cover cisterns in some depth are: [1] the
American Association for Vocational Instructional
Materials’ Planning for an Individual Water System
(available for $7.55 postpaid from AAVIM, 120 Engineering
Center, Athens, GA 30602), and [2] Volunteers in Technical
Assistance’s Using Water Resources (available for
$5.00 plus 95¢ shipping and handling from Mother’s
Bookshelf, P.O. Box 70, Hendersonville, N.C. 28739).
Do a little digging and you just may find that a lack of
ground water doesn’t have to keep you from purchasing that
much-wanted patch of land in the country. Not if you’re
willing — like us — to drink (and bathe in) a
little rainwater now and then.
