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The water being collected by these children for cooking and drinking must be boiled or passed through the sand filter. A teaspoon of bleach added to 20 liters of filtered
water, which is allowed to stand overnight, will eliminate most germs.
A sponsor's worker supervised the capping of this spring. The spring was dug out and cleaned; the standing water was drained; a notched plastic
pipe was laid in the spring; a small dam was built to create a reservoir of water; the reservoir was filled with medium size rock and covered with plastic; the plastic was covered with dirt. Water passes through the
notches in the plastic pipe and by gravity down the hill to the concrete tank (the top of the tank must be below the eye of the spring.) A sponsor's member is assisting in the construction of the tank. Tanks prevent
pollution by animals and store water for times of shortage.
Digging a trench from the spring to the water tank is the first job. This allows the spring to drain and
makes it possible to clean the rubbish, dirt, and debris from the eye of the spring. This spring is being cleaned and capped to provide the clean water for the tank below. A reinforced concrete slab has
been constructed as a base. A corrugated pipe 1-1/2 meters in diameter x 2 meters long is being used and reused as the form or mold for the tank. The plastic pipe to connect the tank to the spring is
cemented into the base. An overflow pipe to supply water for irrigation and animals is also installed at this time.
The trained crew is assembling and wiring the corrugated form together. (The form is reusable for about
50 tanks.) The corrugated pipe or culvert has been cut in half lengthwise and reinforced with angle irons so that it can be bolted or wired together. Note: A 40mm x 140mm wood board spaces the form apart
on one side and when it is removed, the form can be collapsed inwards and disassembled. The other side is bolted or wired together without a space. One of the crew is mixing the dry sand, gravel and
cement together. This must be completely mixed in order to obtain good concrete. Water is added slowly after this. About 10 bags of cement are required for the tank, base, top and dam. Black plastic
is being used to cover the vertical seams in the tank form or mold. This is to prevent the concrete from adhering permanently to the form at the seams. Chicken wire is wrapped around the form and pulled
hand tight and joined by looping the ends together. The chicken wire gives general reinforcement to the concrete.
Over the chicken wire a fencing wire is wrapped around the form in every corrugation to give the tank
burst strength against the weight of the water. The workers are applying hand tension as the wire is wrapped. This tank is almost indestructible.
Here the crew is plastering the first coating of cement onto the side of the form. After a few trials the
right consistency (viscosity) of the cement will be determined by the workers. The only tool needed is a trowel to work the cement completely into the chicken wire. The concrete should be allowed to set
overnight before the second coat is applied.
After the two coats have been applied to the outside of the form, a worker climbs into the tank and
disconnects the two halves of the corrugated pipe form. The 2x6 wood board is then removed and the form is collapsed inward. Once it is broken loose, half of the form is removed. Note how difficult it is
to remove the second half from the concrete. Be sure that the plastic completely covers the vertical joints of the corrugated form. The crew consists of three men who deliver the supplies and perform the
skilled jobs. It is important that time be spent training some of the helpers so they can construct tanks with their own people.
After the corrugated mold is removed, the inside of the tank is plastered. The first coat evens out the
corrugations and a curved filled corner is made between the bottom of the tank and the base. The second coat covers the sides and as much of the bottom as possible to make the tank water tight and prevent leaking.
After the last coat of plaster on the inside has set overnight the plastic pipe from the spring should be
joined to the inlet pipe to allow the tank to fill with water. Note that the outside of the tank is wet when
the tank is filling. This is good because it slows the setting of the cement and makes it stronger. The
spring runs continuously into the tank. When it is full the excess water drains through the overflow pipe. This is used for animals and for irrigating gardens.
Next the empty paper cement bags are laid on the ground to provide a clean surface for the casting of a
cement top. The ends of a piece of plastic pipe 5 meters long are joined together to make a round form. Concrete reinforcing mesh is cut to fit inside the circle of plastic tubing. Concrete is mixed and
troweled deep into the reinforcing mesh. Slightly moving the mesh up during this operation helps but do not expose the wire. This crew is completely local and uses the materials furnished. Note how well the
women mix the cement and create the right viscosity for making the top. It will require several days for the top to cure. It should be covered from the sun and kept moist while curing.
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