Agro-Tech Book - Agriculture Support Programme

fairly common in Zambia and applies 50mm water every week.
PUMPS
There are many different kinds of pumps, some are operated by human power, others by
wind power and others by diesel, petrol or electric motors.
Human powered pumps
“DIAPHRAGM PUMPS” are made in Zambia using wood, and small amounts of metal with
rubber/plastic parts. They are operated by a handle and can be used for low-lift situations.
They cost US$117 and are available from TDAU at the University of Zambia.
“TREADLE PUMPS” are operated by standing on one peddle and then the other alternately.
There are models for high lift and others for low lift. High lift models do not pump as much
water per step as low lift, so the height to which water is to be pumped is important in
choosing a pump. Check how much pipe is supplied with the pump. A non-collapsible suction
pipe is needed and a delivery pipe which can be collapsible.
Pumps cannot suck water more than about 6 metres no matter how strong the operator is.
The suction side of a pump is always more problematical than the delivery side because small
leaks allow air to enter, which prevents the water from entering the pump. The pump should
always be as close as possible to the water to avoid these problems.
When dirt is allowed to enter the pump it will cause damage and stop the pump from working
well. Make sure that the suction pipe does not pull
mud, sand and dirt into the pump. It is best to
have a foot valve with a sieve to protect the pump
and keep it primed when not in use.
Treadle pumps need to be pumped for 2 to 4 hours
per day twice a week for one tenth of a lima of
crop, depending on the maturity of the crop and
the weather.
ZEEOA HPRESS TREADLE PUMP
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E.E.O.A.
AGRO-TECHNOLOGY: Farming and Processing Equipment