Water Access in Emergencies
Practical Action
The illustration beside shows a
typical hand-dug well operation;
the diameter of the hole being dug
is typically 1.5m, which will
reduce to 1.2m when a lining has
been put in. Traditional tools can
be complimented by simple air
and water pumps, and provided
that correct safety guidelines are
followed, displaced people can be
incorporated into the construction
process.
It may be necessary to hand-dig
wells to reach the closest available
water, whilst waiting for
machinery to be brought in to
acquire access to deeper water
tables for a more sustainable
supply.
Figure 12: Safe well digging operation
Source: Davis, J. and Lambert, R.
(2002)
In all methods of machine drilling a borehole, the excavated material must be ‘flushed’ to the
surface, which can be achieved by pumping a fluid through the internal hollow of the drill string,
and forcing it back up the hole; the fluid can be air, water, foam or a combination of several. The
illustrations below demonstrate typical setups for percussion and rotary drilling operations.
Figure 13: a) Lorry-mounted percussion drilling rig: b) Reverse-circulation rotary drilling
Source: Davis, J. and Lambert, R. (2002)
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