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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
Water from any source can be kept in small, transportable tanks; this allows easy control and
distribution to queues, and gives particulates in the water the opportunity to settle, helping with
treatment. From here, it is recommended that each group of 5 people is given two collection
vessels of 10-20L and one storage vessel for water (Reed, B. and Reed, B. 2011).
Provide treatment
The aim of emergency responses is to provide sufficient quantities of adequate quality water,
rather than small amounts of pure water (UNHCR, 2007). It is unlikely that water sourced in an
emergency will be completely safe for consumption; it is standard procedure to assume all surface
water is contaminated. In that respect it is essential to provide basic treatment facilities for
displaced people. There are four main categories of treatment:
Chemical Disinfection
There should be provision to treat the water at the central distribution points and at point-of-use
for individuals. A very first step is to chlorinate main supplies, with a concentration of up to 1%
(UNHCR, 2008). This should kill sufficient pathogens that may be present to make the water a
safe level for consumption. Additionally, if water is allowed to sit in a dark container for a day,
more than 50% of harmful bacteria can die off (Kagaya, S. and Reed, B. 2011). Another benefit
of this is that many of the sediments prevalent will settle, reducing the turbidity of the water and
making future treatment more effective. By performing these actions at water distribution points,
it should be safe enough for those collecting, although additional treatments can be undertaken.
Basic filtration devices can be used, although the development of advanced systems (such as
sand-filters) takes time and will not be ready in the immediate aftermath of a disaster. One of the
simplest options is the use of cloths to separate the largest particulates. Another solution that has
been developed by the Sri Lanka Red Cross is the ‘Clay Pot Filter’, which removes a high
percentage of bacteria. It is an affordable, portable method of providing families and individuals
with good quality water, and is described in more detail in the Practical Action technical brief
Clay Water Filters.
A method of disinfection using solar rays and plastic bottles is SODIS (see Practical Action
technical brief), which is simple to implement sufficient bottles and sunlight are present. Boiling
provides the most effective disinfection of water but requires large energy inputs that often aren’t
available. WEDC provide an information sheet on point-of-use water treatment here. Additionally,
the Practical Action technical brief Water Treatment during Reconstruction covers appropriate
These methods can be used to encourage individual responsibility for water treatment, and are
relatively easy to distribute and demonstrate. This can encourage the participation of
communities at an early stage in reconstruction.
Promote hygiene
The methods to ensure hygienic conditions may or may not be accustomed to the displaced
population in an emergency. It is vital in the initial assessment to understand what cultural
practices exist, and what needs to be communicated to people. The most important practices to
focus on are:
Appropriate use and maintenance of sanitation facilities
Safe disposal of faeces
Hand-washing (especially after defecation)
Safe storage of water (i.e. cover pots)