Hand pumps for water lifting
Practical Action
Advantages
Suitable for deep well application up to 100
metres in depth.
Disadvantages
Expensive to manufacture.
Maintenance requires specialist equipment
and skills. Not suitable for village level
organisation maintenance.
Deep-well piston pump
The design of the deep-well piston pump is very similar to that of the shallow-well piston pump.
The main difference is that the pump cylinder is situated deep underground at a point below the
water table. The cylinder is connected to the pump handle via a long rod called a pump-rod
(Figure 8A). This type of pump is also known as a reciprocating "lift" pump. This pump is capable
of lifting water from depths of up to 100 metres. Typical yields from this type of deep-well pump
at 45 metres depth vary from around 11-17 litres/min. Like reciprocating “suction” pumps, lift
pumps can be converted into force pumps by adding a spout valve, air chamber and trap tube.
Since the cylinder and plunger are located under ground, the maintenance and repair of these
pumps is usually more complicated than that of shallow-well piston pumps. It is necessary to
dismantle the pump, removing the pump-rod in order to access the cylinder. Sometimes the
outside pipe or "rising main" is of a larger diameter so that it is possible to pull the whole cylinder
up to the surface for repair without taking the pump apart. This type of pump is generally more
expensive but has the advantage that a village level organisation can take charge of pump
maintenance.
Advantages
Suitable for a wide range of well depths
including application in wells over 100 metres
deep.
Design can be strong enough to cope with
intensive use.
Disadvantages
Accessing the piston and foot valve during
maintenance in traditional piston pumps is
relatively difficult and may require specialist
lifting equipment.
Newer piston pumps where cylinder can be
removed separately from large diameter rising
main can be relatively expensive.
Selecting a water-lifter
The main questions that need to be answered to determine the most appropriate water lifter to be
used for domestic and community water supply are:
where does the water come from (source); and
where does it need to go (destination)
Figure 11 illustrates the main water sources and destinations and Table 3 summarises the
suggested option for each combination of source and destination.
4
3
5
Figure 11: Main sources and destinations for water
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