Water is the most abundant resource on the earth, since it covers around three quarters of the earth surface. However, up to around 97% of the water on the earth surface cannot be utilized directly since it is not fresh but ocean water. Only approximately 3% of the world’s water can be utilized by humans who use fresh water. Since times in memorial, a human settlement in the desert has been known to occur around the oasis; this was done particularly to ensure the people had a regular supply of clean and safe water. The world arid areas are challenged with limited access to safe water for consumption. The above problem is mostly evidenced in arid areas especially in third world, where access to water for domestic or any other use is limited. This study tries to look into various ways that can be used to supply fresh water to the communities that live in the deserts
Some deserts go for a long period with little or no rain at all; however, in some deserts, there occurs uncommonly heavy downpours. It can be a brilliant idea to create reservoirs or storage tanks to ensure that not all of the water received during heavy downpours or light showers go to the river. This can leave some water for people to use than to allow the water to flow to the rivers and later follow it there. The greatest advantage of this method is that rain water is fresh and may not need further purification. The only costs in this method are spent on the collecting system and storage vessels. The limitation of this approach is that downpours in the deserts occur after an exceedingly long time and their timing cannot be projected. This method cannot provide an all year round solution to the shortage of water in arid areas.
There is little water in the desert, and this creates a need to reuse it after every use. Steps should be taken to ensure that water can be reused again by people. This is useful in saving the resources used to acquire water. The key shortcoming of this technique is that water from can be contaminated after the use; thus, it cannot be purified. The process of treating used water can be hugely expensive for some communities to afford it.
The research done in Italy by the Ministry of Environment around six years ago indicated that ground water is safe for consumption without further purification. Underground water as a resource can be harnessed by the use of wells or sunken boreholes. Although underground water is usually free from microorganisms, it is sometimes hard and may require treatment. In addition, its supply has been found to be constant and reliable. When a borehole is sunk to reach certain deep aquifers, it is observed that the water does not dry up even during the drought season. This may be particularly useful in the dry season as people can have a regular supply of water all year round. The limitation of exploitation of underground water is that it can be extremely expensive and requires a lot of resources to exploit. It is extremely expensive to sink one bore hole. Even after a borehole has been sunk, much more resources are required to get the water. The implication of this is that poor people living in arid areas, especially in the third world countries, cannot utilize this resource in spite of it presence. Sometimes poor people living in deserts apply a lot of pressure to wells that get their water from shallow aquifers. Sometimes this leads to the wells drying up (Al-Kharabsheh, 2003). Another disadvantage of a shallow aquifer is that it is close to human activities and can be easily contaminated.
The recent research shows that the existing strain in fresh water sources, especially in arid areas, can be eased by shifting a focus to salt water. This can be done through desalinization. Desalinization is a technique done to remove salts from saline water to make such water suitable for human consumption. This process has been done in Asia at a cost equivalent to the cost of normal distribution of fresh water. This can be considered in water policies of many nations, and it can have far reaching consequences in reducing the current undue pressure on the fresh water sources. The ability of desalinization to convert hard water to soft water makes it suitable for the domestic and industrial use. The major disadvantage of this process is its cost. It requires expensive machinery and chemicals which cannot be afforded by some desert communities, most of which are poor. However, with the help of a government and other organizations, these communities can utilize this technique to acquire an adequate supply of fresh and safe water.
Another supply of water in arid areas that has not gained popularity for a long time is dew harvesting. In some places, the annual amount of dew has been seen to exceed the annual average rainfall. In Israel, people have used plastic sheets to collect enough water from dew to grow seedlings. In Australia, large polythene sheets have been used to harvest enough water for drinking which is stored in emergency supplies reservoirs. The water collected from dew is considered fresh and does not require any further purification for it to be safe for the use. There are advanced methods of collecting dew from the sky through the use of aerial wells, which have been used to provide drinking water in some places. This process is made possible through the condensation of intercepted mist or fog, which is done in the atmosphere. The collection of dew and mist has disadvantages. These methods used may still be not affordable to poor people living in the desert. In most cases, the collection of dew requires a large polythene sheet which is expensive and not particularly durable. The collection of mist through various processes requires specialized skills, especially in the creation of aerial wells; these skills may not be readily available to poor communities living in the desert. A major disadvantage of both dew as well as mist or fog collection is that in both processes a limited amount of water is gathered, and none of the two methods of harvesting water can supply all the water that a community may need. These methods can only be used to supply water for emergency needs only.
Lack of water and specifically for domestic use has been the greatest and the most limiting resource to the human development in arid areas. Supplying such areas with fresh water would mean their development, as well as, betterment of human living conditions of such places.
All methods described above can be used in supplying this crucial resource to people living in such areas. However, the change goes further and deeper than just the mention of the processes or techniques that can be used. For instance, these or any other technique will require resources in terms of finance to install them.
Secondly, the attention should shift from the technique to the provision of necessary skills as how some of these techniques should be scaled down to a community level (Delwynn, 1998). The possibility of these techniques being applicable at either personal or family level should be evaluated. For instance, it would be more economical for one family unit to reuse the waste water at the household level than to collect the water to a common place, to treat and to distribute it. This is mainly because collecting together the waste water and the redistribution of clean water requires a system of canals. The concerned community, the government as well as various organizations involved should engage themselves in an intensified consideration in order to weigh out options. This will help them to identify the technique that works best to solve the problem specific to their area.