Lack of fresh water for agricultural, domestic, and industrial use is a great hindrance to development in many parts of the world. According to Mwakikagile, water shortages are more prominent in the arid and semi-arid areas. Groundwater is very sensitive to climatic changes and agricultural exploitation. Over the past few years, groundwater extraction for purposes of irrigation has resulted in disruption of natural balance and aquifer overdraft in these regions. According to Rushton, groundwater reproduction is imperative to establish apposite management policies since the hydrology of arid and semi-arid regions is quite different from that of more humid regions. This report comes up with several possible methods of providing water in arid areas, and also gives a few recommendations on how to tackle water scarcity in these regions. The specific area that I am going to tackle is Garrisa District, found in the North-Eastern Province of Kenya.
In Garrisa, insufficient water for household, crop, and livestock use has been a major development hindrance. This area receives very little rainfall, but extremely high rates of evaporation. The seasonal rivers that supply water in that region can only do so during the rainy season, and even then, the water is too little to help out much. According to Obudho, women in these areas walk 10-20 kilometres every day in search of water. Children also end up missing school because they have to go look for water. According to Misstear, the amount of water they get is too insufficient to sustain a whole family, thus the water consumption per person is usually between 2-4 litres a day; and this water is supposed to cater for all purposes, namely drinking, cooking, and washing.
Reasons for retaining water:
There are only two rainy seasons every year. The long rains fall between March and May, whereas the Short rains fall between October and December. Therefore, no rain is received outside of these seasons, and that is between May and October. (This is clearly demonstrated in the graph below). In addition to that, there are no permanent rivers or lakes in Garrisa. Since the communities inhabiting this region do not have the funds to fund any water projects, they have to rely on the Government and well-wishers to assist them.
From the above information, it is evident that very little amounts of rainfall are received throughout the year.
According to Norton, much of Garrisa’s problem can be solved by improvement in the methods of capturing and retaining rain water. There are several low-technology, low-cost methods that can be employed to harvest and retain precipitation. These options include:
a) Collection of run-offs from the roofs: This option requires the presence of a tank.
b) Sand dams: These store water on seasonal river beds.
c) Boreholes: These are used to extract groundwater.
Potential water amounts percentages that could be acquired from the above sources are represented in the graph below:
From the above graph, it is clear that boreholes and sand dams have the potential to provide more water than the other possible sources.
In this report, I am going to divulge into the options of sand dams and boreholes, and recommend the better option of the two.
A borehole is an extended, narrow well drilled to reach underground water. According to Misstear, a test borehole must first be drilled to guarantee the presence of water. Water-levels must be measured, and several samples sent to special laboratories for examination. In case the results are inconclusive and the tests have to be repeated, a lot of resources end up being wasted.
Nonetheless, once drilled, the borehole is reinforced with a special sleeve that prevents the hole from collapsing. It is then covered with a hand pump, which serves to prevent contamination, while easing access to the water. Proper maintenance and care can make a borehole last up to 20 years.
Benefits of using boreholes:
i) Water obtained from boreholes is usually free of harmful micro-organisms, especially if the source is natural, pure, and protected.
ii) Boreholes are a sufficient and reliable means of providing water. No water bill requires to be paid at any time, and unexpected water shortages are also absent.
iii) Boreholes provide easy access to water, and women do not have to walk for hours in search of water. Moreover, children do not have to miss school.
iv) The time saved can be utilized in performing various activities that could provide earnings to the women, which could bring about socio-economic developments.
v) Accidents that may result from using wells are also prevented, as well as the time restriction of fetching water only during the day.
vi) A borehole can be drilled and start functioning within a period of one week, and can thus be applied to counter emergency water needs.
Disadvantages of using boreholes:
a) Boreholes require regular servicing, which may not be possible in case the users are unable to maintain them.
b) The initial cost incurred while drilling a borehole is quite high.
A sand dam is a toughened concrete wall constructed across a seasonal river bed. To locate the best site for a sand dam, a survey has to be conducted first. During the actual construction of a sand dam, the local community can easily take part. According to Norton, this can be in the form of collection of the stones, water, and sand essential for the construction. This can reduce the total costs by half. Furthermore, with proper maintenance, dams can lust up to 30 years.
Benefits of sand dams:
a) Sand dams deliver a year-round supply of water, and thus women do not have to countless hours searching for water. Children also get to go attend classes more often.
b) The time saved also means that the people can engage in more productive activities such as the growing of crops that can sustain households.
c) The water acquired is quite clean, as it goes through filtration processes as it passes the layers of sand.
d) Cleaner water means fewer incidences of diarrhoea and typhoid.
e) The self-fulfilment that the community experiences from taking part in an initiative meant to help them is priceless.
f) A sand dam can easily transform the environment, in that it can raise the water table on both the upstream and downstream end of the dam. This can then increase the survival rates of plants that would have never survived in the dry land.
g) Sand dams help in the control of soil erosion, and also increase infiltration of moisture into the ground water.
h) Maintenance of sand dams is quite simple, as only the lower riverbanks require protection from soil erosion.
Disadvantages of sand dams:
I) Construction of a sand dam is quite labour intensive, and thus requires massive co-operation with the local community.
II) Capital required to purchase materials necessary for the construction is quite high.
Following the above comparisons, it is clear that both boreholes and sand dams are possible water provision methods in Garrisa, as either can be successful. Although both have disadvantages, the advantages outweigh them in both cases. Even though boreholes supply enough water for consumption, sand dams provide more water, which can also be used for extensive farming. Both methods may require a lot of starting capital, but the costs incurred after they have started working are negligible.
1) Sand dams may be the better option in this particular region, as they require less operational costs, and their maintenance is quite low.
2) Sand dams also last longer than most boreholes, and therefore they are the safer bet.
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Mwakikagile, G. (2007). Kenya: identity of a nation. Dodoma: Godfrey Mwakikagile.
Norton, M. (2007). 365 ways to change the world: how to make a difference one day at a
time. New York: Simon and Schuster.
Robert A. Obudho, J. B. (2000). Issues in resource management and development in Kenya:
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Rushton, K. R. (2003). Groundwater hydrology: conceptual and computational models. New
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