Free Different Techniques For Providing Fresh Water To Arid Regions Of The World Report Sample

An evaluation of the feasibility of different techniques for providing fresh water to arid regions of the world

Many areas in the world are arid, according to Howard et al. (2010 p.26) it is appraised that 30 percent of the total land in the world is semi-arid or arid. These areas do not have water bodies like rivers and lakes to supply them with fresh water and those that have these resources are seasonal and cannot support life throughout the year. Water is a valuable resource for life and serves humankind in domestic capacity, agriculture, tourism, energy, and industrialization. In addition to limited water access, these areas also face the problem of quality deterioration resulting from changes in the hydrological cycle. This is causing water in these regions to become increasingly salty because the aquifers are being destroyed. Population growth, industrialization, urbanization are factors putting pressure on water demand in arid regions. Water shortage in the semi-arid and arid areas has slowed down economic and social development (Howard, 2010). They argue that for development to be sustainable water resources need to be managed sustainably so that constant supply is guaranteed. This report aims at identifying methods for providing water in arid areas and reviews their feasibility, in the long run.

Harvesting of ground water

The amount of surface water has been on a steady decline over the years. According to the National Academy of Sciences, harvesting ground water through the drilling of boreholes is a viable method of providing fresh water in arid areas. This method is economically feasible because there is minimal maintenance cost following the initial cost of drilling. Ground water is also considered clean and safe to consume and, therefore, eliminates the cost of water treatment. Fears may be raised about the safety of underground water especially if the boreholes are not covered as this may result in contamination (Koundouri, 2006). In such cases, it is recommended that additional steps to purify water be taken such as chlorination. There are also instances of underground water being salty, and it's a challenge to get rid of this salt, however Boiling and chemical treatment help reduce the salt levels.

Desalination

Desalination is a process of removing the salt concentration in the sea water to make it fresh drinking water ( Paton ,2009) hold the view that desalination is a feasible method to ensure a constant supply of fresh water in these areas. Studies by United States department of geological survey (USGS), the technique involved desalination process removes most of the contaminants in the water. In the year 2012, it was approximated that there were about 12,500 desalination plants in 120 countries all over the world. Desalination involves three primary processes namely pretreatment, desalination and post treatment. Pretreatment involves removal of impurities such as algae, silt, bacteria, plants and non-biodegradable wastes in the water. Desalination involves two processes; thermal process and membrane process. Post treatment process involves blending desalinated water with water with high dissolved content, aerating and disinfecting the water to balance its taste before releasing it to the supply network. The benefits of using desalination include; unlimited water supply, costs of maintaining and operating the plant can be reduced if the system is correctly utilized, the size of desalination plants can be expanded and high-quality water from the processes. The process of desalination can also use renewable energy sources such as wind, solar and geothermal that is readily available in these arid areas.
The disadvantages of using desalination include high energy requirements although as technology advances ways of using low heat, and recycling heat are being developed to make the projects sustainable. Disposing of the salt concentrate (brine) is the biggest challenge. The processes are technical, and high levels of training are required. The initial cost of installation of plants is high. The process also uses other chemicals that may pollute the environment if not well disposed. Arid countries that are landlocked can import treated water or enter into agreements with countries with a coastline to carry out a joint desalination. The cost of purifying water through desalination is high but justified by the extinction or non-existence of conventional sources. Many countries in the arid have adapted desalination to provide water for domestic use and agriculture to their citizens (Koundouri, 2006). Examples of these countries include United States of America, Australia, Saudi Arabia, United Arab Emirates, Israel, and Qatar United Kingdom among others (Shemang and Chaoka, 2004). On the other hand, states of Florida and California are some of the world's highest consumers of desalinated water with about 6.5 percent of world's production. It has contributed to their social and economic development and thus it has proved a viable method to supply fresh water in arid areas.

Dams

These are reservoirs built to contain water supply for irrigation and use domestically and in industries. They also provide hydro-electric power and minimize flooding. Dams may be constructed along rivers or in the area with natural or artificial topographical depressions to store rain water and runoffs from roads, streets, and drainages. This water may contain a wide variety of contaminants, and so it would not be safe for consumption. However, this water can be used for agriculture. This technique has been applied in Brazil, Paraguay, and Argentina. The advantages of this method are water collected can be used for cultivation in arid and semi-arid areas; they help to reduce floods and erosion, the cost involved are small if the sole purpose is water storage as opposed to power generation. The disadvantage is that these reservoirs are sufficient where the soil is less permeable, high contamination from litter and debris, evaporation may reduce the effectiveness and the stagnant water may be a breeding site for mosquitos thus it becomes a health hazard to people living in the surrounding.

Seawater Greenhouse technology

Another technique of providing fresh water in arid areas is seawater greenhouse.it is a method that was brought to the consideration during the fourth world conference on the future of science held in Venice in Italy in 2008. The method uses solar technology to evaporate sea water that has been diverted from the sea to depressions in arid areas. The water later falls back as rainfall in the dry areas. There are more than 200000 hectares of land where seawater greenhouses within the Mediterranean region that has resulted in a 10 percent annual growth rate since its implementation (Paton & McCalman, 2008). Additionally, regions such as Oman and Abu Dhabi can now do agriculture using fresh water from this technology. Other countries, where this technology has been implemented, includes Egypt, Libya and Tunisia and provides water for horticulture.
In conclusion, Water scarcity is a challenge to many countries all over the world and more so in the developing countries. With the growing population and climate change, a lot of pressure has been exerted on existing conventional water resources, raising the need to look for alternative water sources. Amid these challenges, it is important that governments in arid areas review the various options available to provide citizen with water for irrigation and domestic use. This paper reviewed the feasibility and application of the following methods, Ground water harvesting, dams, desalination, and seawater greenhouse. Depending on the technological level, available resources and prevailing conditions in a country, the government may decide on the appropriate strategy.

Reference List

Howard, W, Mathias, S & Xin, L. 2010. Groundwater Modelling in Arid and Semi-Arid Areas, Cambridge University Press, Cambridge.
Koundouri, P. 2006. Water Management in Arid and Semi-arid Regions: Interdisciplinary Perspectives, Edward Elgar Publishing, Cheltenham.
National Academy of Sciences .2001. More Water for Arid Lands: Promising Technologies and Research Opportunities, The Minerva Group, Inc., Honolulu, Hawaii.
Paton, R. A., & McCalman, J. (2008). Change Management: A Guide to Effective Implementation. London: Sage Publications.
Shemang, S & Chaoka, R. 2004, Water Resources of Arid Areas: Proceedings of the International Conference on Water Resources of Arid and Semi-Arid Regions of Africa, Gaborone, Botswana, 3-6 August 2004, Taylor & Francis, New York.