Rainwater harvesting in Uganda
Practical Action
Partnership working: To work in partnership with local organisations.
Design of the systems used.
Tank
Gutters
The DRIP tank is a fired brick built cylindrical tank
standing on a base of approximately 1.5m
diameter.
To provide a foundation for the tank, a circle of
1.5m diameter is excavated to a depth of one
brick). A level, circular base of bricks on sand is
made in the excavation, and the bricks are then
interfilled with cement.
From the edge of the base, a circular wall of bricks
is built to a height of approximately 1 metre to
make a cylinder (dependent on the clearance of the
overhanging roof). This is a similar building
technique to that used to make a hut.
The outside of the tank is then rendered smooth
with cement.
A different cement mix is made using waterproofing
agent to render the inside walls and base of the
tank.
The gutters used are those available from
local sources, usually a U-shaped metal
gutter with wide wings. This allows for the
overlap of a round roof with a straight
gutter. One half gutter is used to bridge
between the roof and the tank.
To minimise the risk of termites eating
wooden supports, the gutters can be
suspended from the roof by ropes. This
also allows the gutters to be removed
quickly in the event of the tank being full,
or during the dry season.
Wooden supports can be used and are more solidly positioned. Either they are treated with
termite protection or they are replaced when necessary.
Lid
The lid of the tank has to provide a long-
lasting cover against sunlight, insects
and debris entering the collected water,
whilst being removable to allow removal
of the water. This is particularly
important in areas where malaria is
present, as the tanks would otherwise
become mosquito breeding centres.
The lid is made from two sheets of
corrugated iron, cut to shape with an
overlap. One is cemented to the tank,
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