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Water Issues
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Page Contents:
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How
Projects are Managed
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Aims
and Objectives of the Water Programme
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Simple
Technologies for Water Harvesting and Conservation
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Rock
Catchments
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Small
Dams
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Sub-Surface
Dams
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Shallow
Wells
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Using
Appropriate Technology
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The
Position of Women
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Why should we support
water projects in Kitui?
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Easy
access to safe water is a basic human right.
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The
majority of the people of Kitui are denied this right.
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In Kitui, many have to walk long distances- sometimes more
than 10 km each way- to get water.
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The burden of fetching water falls on
women and girls in Kenya.
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Time
spent fetching water is time unavailable for providing the basic
necessities of life
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Click to enlarge
A typical
rock catchment constructed as a
joint effort with the local community
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| The
amount of rainfall in the arid and semi-arid lands (ARALs) like Kitui is not the
problem. Kitui
diocese has annual rainfall in the range 250mm-800mm, not hugely different from
Dublin. However, unlike Ireland, the rainfall comes in intense bursts of short
duration, and at specific seasons. Daytime temperatures are
such that rapid evaporation occurs. |
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Much of Kitui's water problem
can be
solved by simple methods of retaining rainwater.
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There are
several low-cost, low-technology systems which can be used to great effect.
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For as little as €1500 you could provide a
safe water supply for up to 200 people.
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Friends
of Kitui will sponsor a minimum of 15 water
projects in Kitui in the coming year.
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Each
project will typically provide safer drinking water for
200-250 people.
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| In this section we will try to give a broad overview of the
water situation in Kitui. The
amount of rainfall in the arid and semi-arid lands (ARALs) like Kitui is not the
problem:
the problem lies in the distribution of that rain fall, in space and time. Kitui
diocese has annual rainfall in the range 250mm-800mm, not hugely different from
Dublin. However, unlike Ireland, the rainfall comes in intense bursts of short
duration, and at specific seasons, and of course the daytime temperatures are
such that rapid evaporation occurs. Much of Kitui's water problem could be
solved by improved methods of retaining or capturing precipitation. There are
several low-cost, low-technology systems which can be employed to retain, or
harvest, rainfall. Friends
of Kitui will support simple, practical projects with
a high chance of success. |
The problem is NOT insoluble.
With your help, and at
relatively low cost,
we can help implement methods for rainfall harvesting which will make a real
difference to the lives of thousands of Kitui's people.
Projects currently being supported are shown on the Current
Projects page
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The overall aim of the programme is to:
“Improve health and
productivity through provision of clean water through community
empowerment for sustainability development”
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Five specific objectives have been adopted by the Water Programme as follows:
- To
improve water availability by reducing the distance to water sources to less
than 5 km from the homestead
- To improve women’s access and control over
resources.
- To
cause positive change in health and hygiene practices.
- To impart knowledge on improved
conservation measures to prevent desertification.
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Community
Participation
– The communities are required to contribute local materials
and in some cases cash towards the cost of the project. In some cases this
amounts to 40% of the total project cost. This has to be negotiated with the
project group prior to the start of the construction and forms part of the
mobilisation process. |
At the same time the groups are encouraged to put in place
a long term revenue collection system which can provide them with the necessary
funds to carry out routine operation and maintenance or even project replacement
or replication. |
Construction of Water
Points – The
programme concentrates on small scale technologies such as shallow wells, rock
catchments and sand dams which are appropriate to these ASAL areas. Projects are
selected according to predefined criteria relating to their level of
organisation and commitment to contributing to the project. The programme
aims to provide the following
- Shallow Wells (up to 30m depth, with
hand pumps)
- Rock catchments
- Sub surface dams
- Water harvesting (e.g collection of
rainfall from roof surfaces)
- Earth dams
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Acknowledgements: This summary
draws on material from several sources freely available on the Internet, particularly Research Report RR 6.
The
water resource in tropical Africa and its exploitation, by the International
Livestock Centre for Africa, PO Box 5689, Addis Ababa, Ethiopia.
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It is often said that the
amount of rainfall in the arid and semi-arad lands (ARALs) is not the problem;
the issue is in the distribution of that rain fall, in space and time. Kitui
diocese has annual rainfall in the range 250mm-800mm, not hugely different from
the eastern half of Ireland. However, unlike Ireland, the rainfall occurs in intense bursts of short
duration, and at specific seasons. Thus for the Kitui district, the short rains
are expected in November, and the long rains are expected during March and
April.
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Some areas of Kenya have plentiful water supplies: however it is of no
help to know that nearby humid areas have plentiful water if the costs of
distributing that water far outweigh the economic returns. It is technically
feasible to pump water from lakes and distribute it by pipelines to almost any
pastoral area. Saline water can be desalinated and rivers impounded to provide
supplementary water supplies. These methods, however, are extremely high-cost
solutions and cannot usually be justified. |
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simplest form of water exploitation is to store at the river bank or lake shore.
All other forms of water exploitation require the use of technology, hand or
machine powered, which must be appropriate to the local conditions. For the
Kitui diocese, the only practical sources of water are from boreholes (expensive
and far apart), shallow wells (require groundwater supplies, in turn recharged
by rainfall), or from sand dams or rock catchments. Because of the long
intervals between the rainy seasons, storage reservoirs with open surfaces are
of limited benefit, due to the very high evaporation rates.
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| Rainfall
harvesting is the term given to the conservation and storage of rainfall on
outcrops and sheets of bare rock. The term can be extended to include sand dams
formed in the beds of seasonal rivers. In many parts of the tropical pastoral
regions there are rock outcrops which stand out prominently from the surrounding
plains and receive additional precipitation from rainfall, dew and mist.
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By
encircling such rocks with a low masonry wall the runoff from the rock catchment
can be guided into a natural storage area, blocked off with a concrete wall.
Many rock catchments and storage tanks have been successfully constructed in
Kenya as part of the surface water conservation programme of the Ministry of
Agriculture.
Even
in the arid zone with an annual rainfall of less than 250 mm more water runs off
the rock during a short storm of shower than can be effectively and economically
trapped and stored.
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the most common form of water conservation structure is a small earth dam across
a water channel which may have permanent or seasonal flow, and which can be
constructed without professional engineering advice.
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A narrow, steep-sided
valley allows the design of a short dam wall of considerable depth and a small
surface area of open water which will be less susceptible to evaporation losses.
A wide flat valley calls for a long wall, which may be costly, and which will
result in a large surface area of open water and high evaporation.
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How the Sub-Surface dam is constructed
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method of evaporation control is to use sand rivers as storage reservoirs. This
technique has been used successfully for some years in East Africa where the
reservoirs are known as subsurface dams. The technique depends for its
effectiveness on the availability of an extensive bed of coarse sand, and many
such deposits can be found in the Kitui diocese. By constructing a low weir or
wall at a convenient rock bar, coarse particles can be encouraged to settle
upstream of the weir. If the height of the weir is raised after successive
floods, fine particles tend to be carried over the weir and a deep bed of coarse
sand can build up behind the wall. This is known as “phase lifting” of the
dam and is usually done one or two years after the initial construction. |
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A
shallow well can be sunk into the sand bed about 100 metres or so from the wall
of the dam, and with suitable sand filtering can provide potable grade water for
human consumption. With careful
construction, such subsurface dams can function without trouble for many years.
The storage capacity of the reservoir is determined by the voids or spaces
between the coarse sand particles, and typically amounts to 30 and 50% of the gross reservoir volume. Well chosen sites
can drain quite considerable stretches of river, albeit slowly, and this method
can sustain small livestock populations throughout the dry season. No particular
skill is required in constructing the low weir, and pipes can be laid to cattle
troughs, incorporating valves or taps to control wastage.
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cost of constructing a sand dam, or sub-surface dam, is approximately €4,000-
as measured by the external funding contribution required by the community. Such
a dam can provide water for a community of 200 to 300 people, including their
livestock. The system which has evolved for constructing these dams is a
co-operation between a community group and a donor organization.
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The community group makes an application to the
for
support, citing the number of participants in the project, and committing to
providing local labour and materials. The community contribution is typically
60% of the total project cost, as measured by the value of the labour and
materials they provide. The subsequent “phase lifting” of the dam, described
above, will cost a similar amount of €4,000, and increases capacity further.
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A SASOL sand dam in Kitui |
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In
addition to sub-surface dams, shallow wells are another suitable source of water
for much of the Kitui diocese. If the water level is less than 10 m from the
surface, it will be relatively cheap and quick to dig a well by hand. Such wells
are known to have been dug to great depths, up to 120 m. Because of the cost and
scarcity of mechanical equipment for digging wells, hand-dug wells will continue
to be constructed to considerable depths, even though they may not represent the
most economical option.
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Hand-dug
wells are one of the oldest means of water supply. Begun as simple water
holes in sand rivers, the concept of finding water by digging in riparian
areas has spread away from the river course itself and, particularly in
West Africa, deep hand-dug wells, reaching up to 100 m in depth, are used
to tap deeper shallow aquifers and areas of basal seepage around rock
outcrops and escarpments. One
advantage of a dug well over a costly borehole is that community participation
is assured from the start.
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women and children can all help with the fetching and carrying of sand and
gravel. A rural community thus identifies itself with the construction of the
dug well, and this sense of communal ownership is vital if the water point is to
continue to function.
Open
wells afford very little protection against pollution, even when low parapets
are constructed to prevent the ingress of surface water.
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Any water-lifting
techniques involving the introduction into the well of ropes and buckets which
are handled or have been exposed to contamination will create a possible source
of faecal pollution. More sophisticated lifting devices, such as hand pumps,
will require maintenance of one sort or another. If no maintenance facilities
can be provided, open wells will be a better option.
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If, on the other hand, the
hand pump is suitable for village or community level maintenance, and the
frequency of use of the water point is high, it is preferable to aim for a fully
protected well.
For
this reason, well digging should take place at the end of the dry season when
static water levels are at their lowest.
In
nomadic societies, water is still being raised from wells by leather buckets and
ropes, or by a team of several men standing one above the other and passing the
water upwards in small containers.
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To anyone who has observed this operation
used to water a large herd of cattle the hourly output is impressive, and is
witness to the energy which men are prepared to expend to safeguard their herds.
Such traditionally developed methods, however primitive, are adapted to the
situation and are an appropriate technology, if not always the most efficient.
In contrast the reluctance of these same people, who are willing to expend great
manual effort, to contribute money for the operation and maintenance of modern
mechanical equipment is manifest in many instances, even if the money is there
and the service is generally appreciated.
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appropriateness of any mechanical device is determined not only by its
reliability and simplicity in operation, but also by its acceptance by the
users. For example, it has been the East African experience in pastoral areas
that attempts to replace the bucket and rope, or chain of men, with a hand pump,
which allows the top of the well to be sealed and the water kept free from
pollution, have not been successful because it was claimed by the users that the
hand pump was more energy consuming and had a lower output. Hand pumps fitted on
wells were neglected, frequently vandalised or abused to the point of breaking
the surface equipment. They were soon discredited and abandoned.
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It
has certainly been the East African experience that equipment bought from the
developed world by the State or by private individuals, or presented by
well-meaning donors, without insisting that the manufacturer at the same time
establishes a spares holding and servicing agency, has soon failed. Borehole and
other installations have been known to stand idle for months or even years,
awaiting the arrival of a small but essential spare part. Many have, in the end,
been replaced by other plants supplied by locally established agents, in whose
interest it is to ensure that their reputation, and hence their business
turnover, is maintained, and that their products and their back-up organisation
give good service.
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Another
neglected factor is the place of women in rural water supply schemes. Women are usually responsible for the supply of
water to the household, and they should be involved in or made responsible for
maintenance. When this has been done, it often results in a marked decrease in the number of repairs.
There are many difficulties in giving women responsibility for operation and maintenance activities in societies where,
traditionally, men are responsible for "technological" tasks.
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Resistance
is likely to be strongest in
pastoral groups where the position of women in society is relegated to a menial
or subservient role.
On
the other hand, responsibility for site selection and construction of water
supplies is vested in women in many West African countries. Ultimately, women
may be more reliable in ensuring the continued operation and maintenance of
water supplies because they have a greater vested interest in their continuous
operation.
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