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< prev - next > Disaster response mitigation and rebuilding Emergency relief KnO 100648_Water Supply during emergencies (Printable PDF)
Water Access in Emergencies
Practical Action
Practical Solutions
Emergency responses are predominantly co-ordinated by humanitarian agencies, and whilst
planning for PCR-based initiatives is recommended at early stages of reconstruction, it can be
difficult to implement them until a stable situation has been reached. However, there are several
examples of appropriate technologies that could be useful in emergency stages, encouraging
community participation whilst still enabling water supplies to be secured. A selection of them is
highlighted here:
Hand-powered percussion drill
A hand-powered version of a percussion drill was
developed by farmers in Kassla, Sudan, in order to
provide an economic and transportable method of digging
wells. Much of the region suffered from water scarcity,
and the majority of the population were unable to afford
drilling trucks. The drill design can be constructed with a
variety of materials and requires considerable unskilled
labour, which can involve local products and people.
The drill could be implemented in emergency situations
with relative ease, and could improve the digging of
shallow wells in cases where machinery is unavailable for
deep boreholes. The Practical Action technical brief Well
Digging in Kassala: The Hand-Powered Percussion Drill
has more details.
Figure 14: Principle of Hand-powered
percussion drill
Source: Practical Action
Human-powered pumps
Practical Action has produced a guide on relatively simple
hand pumps that cost little to install and maintain and
are suited to use in areas where water infrastructure is
limited.
Any shallow well that is dug in an emergency will require
a mechanism to bring the water to the surface; a common
solution is to use a reciprocating suction pump, which
has a plunger or piston which moves up and down in a
two-valve closed cylinder. As the plunger moves upward it
forces water out through the outlet valve and at the same
time draws water into the cylinder through the inlet valve.
Moving the plunger down brings it back to its starting
position. See Practical Action’s technical brief Human-
powered handpumps for details.
Figure 15: Suction pump operation
Source: Practical Action
Treadle pump
The treadle pump is a human-powered device that utilises
two cylinders driven by a person’s legs. The twin pumping
makes it more efficient than a hand pump, and leg
muscles tire less easily than arm muscles. A large
proportion of the device can be assembled from local
materials, with only the pump itself requiring external
manufacture. The pump can be used to draw up water
from shallow wells, and could be used in conjunction with
a hand-powered percussion drill as a practical way of
locating and abstracting groundwater. This is another
solution which could be implemented in emergency
situations if a relief agency is unable to provide sufficient
infrastructure. See Practical Action’s technical brief
Treadle Pumps for more details.
Figure 16: Treadle pump components
Source: Practical Action
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