There has been a significant water crisis in various regions of the world over the last few years. Only about 3% of the water in the world is fresh; therefore there is relatively little fresh water available in some regions of the world, these regions are called arid and semi arid regions. The FAO (1987, cited in IFAD,n.d) defines arid and semi arid regions as “areas falling within the rainfall zones of 0-300 mm and 300-600 mm, respectively”. In other words, arid and semi arid regions are regions in which there is insufficient rainfall and rainfall patterns are liable to significant fluctuations. Some arid regions are in North Africa, South America, some parts of central Asia and the Middle East as well including countries like Kenya, Lesotho, Egypt, and Morocco, among others.
Figure 1: Areas experiencing water scarcity in the world.
Source: International Water Management Institute.
The main problem arid regions encounter is the inadequate amount of rainfall available in the regions and the wide variations in the reliability of rainfall patterns. The average rainfall in arid regions varies between 100 and 300 mm per year (FAO, n.d), compared with over 500mm in other regions of the world. Also, arid areas face the problem of the shortage of fresh water provided by rivers and lakes and this shortage has caused health, agriculture and economic problems for instance, in Kenya, where “over 10,000 children die every year from diarrhea caused by unsafe drinking water and poor sanitation” (WaterAid, n.d) and some parts of central Asia where there is not enough water to cultivate plants. This report evaluates the feasibility of two different water provision techniques: desalination and ground water pumping; that can be used to provide fresh water to arid regions of the world, considering the type of technology used, cost, volume of water produced and the quality of water in addition.
2.0 DESALINATION OF SEAWATER.
Seawater contains high concentrations of salt and other minerals, which makes it unsuitable for human consumption and agricultural practices as well. Desalination is the process by which all or most of the salt and other impurities is removed from seawater by a series of processes in order to make it suitable for human use.
2.1 TECHNOLOGIES AND COST.
For desalination processes, large-scale technology is used; various desalination techniques have been developed in recent years, including primarily, the thermal and membrane processes. In the Middle East region, thermal processes are the most extensively used desalination technologies, accounting for more than half the world’s installed capacity, while membrane processes account for two-third of contracted capacity (Henthorne, 2009). Desalination methods are quite expensive; these costs are derived from a combination of initial investments for construction, equipment, operation, as well as maintenance and management (Younos, 2004). In addition, large-scale desalination...