The Different Techniques for Providing Fresh Water

The world is currently facing a problem of scarcity of fresh water resources. In many of the arid regions of the world, the need of additional sources of fresh water is very important. This is because many arid areas lack availability of fresh water resources such as rivers and lakes. Arid regions are served with limited underground water resources (Perlman 2011). However, water from these resources is increasingly becoming salty due to the continued distraction from the aquifers. There is a need to ensure that arid regions have a constant supply of fresh water in order to ensure continuity of life in these regions (Perlman 2011).

One of the methods that can be used to ensure supply of fresh water to arid regions of the world is desalination (Perlman 2011). Desalination, also known as distillation, is one of the oldest methods of treating water. Currently, desalination remains to be the most popular method of treating water. Desalination is a very feasible method of supplying fresh water to arid regions of the world. This is because; the method has been in use even before the civilization era and the industrial revolution. During the ancient times, travelers would use desalination to get drinking water while on voyage on the sea/ocean. In the modern world, desalination is still used on ships. Modern ships are installed with desalination plants, which convert seawater into fresh water. Apart from seawater, which is salty, over the years, desalination has been used to treat water that has been contaminated by natural or unnatural pollutants.

According to the U.S. department of Geological Survey (USGS), “desalination is perhaps the one water treatment technique that most completely reduces the widest range of drinking water contaminants) (Perlman 2011). For this reason, desalination can be used to ensure that arid regions of the world have a constant supply of fresh water. Studies indicate that by the year 2002, there were around 12,500 desalination plants in 120 countries of the world. These plants produce around 14 million m/day of freshwater. Although the production of these plants is very low compared to the world’s daily consumption of freshwater, they contribute greatly in supply of freshwater to countries located in arid regions. If more desalination plants were to be constructed in all arid regions of the world, then their production of freshwater would increase, hence contributing more to supply of freshwater to arid regions.

In addition, facts about desalination indicate that many of the countries of the Middle East region depend on desalination technology for supply of freshwater (Gratzfeld, 2003). These countries include Saudi Arabia, Qatar, the United Arab Emirates (UAE), Kuwait, and Bahrain. Some of these countries have been experiencing positive economic growth over the last few decades, while depending on desalination for freshwater supply (Gratzfeld 2003). Availability of freshwater is very vital for development of an economy, because all domestic water requirements need freshwater. This indicates that desalination technique is a very feasible method of supplying freshwater to arid regions of the world. Countries located in arid regions can prosper economically while depending on desalination as a sole supply of freshwater.

Furthermore, in the United States, residents of California and Florida states depend on desalination technology for supply of freshwater (Gratzfeld 2003). California and Florida account for 6.5 percent use of desalinated water in world. These states have continued to experience good economic development despite lack of availability of natural source of freshwater, thanks to desalination technology. This provides more evidence about the feasibility of desalination as a source of supply of freshwater to arid regions of the world.

Another feasible source of freshwater to arid regions of the world is Seawater Greenhouse (Paton 2008). This method of supplying freshwater to arid areas was proposed during the Fourth World Conference on the Future of Science in September 2008. Seawater greenhouse technology combines with the technology of solar energy. Here, seawater is diverted to various inland depressions located below the sea level. Then, solar power plants installed inside the inland depressions are used to produce energy for inducing high rate of evaporation of the water. Large quantities of seawater are evaporated, which falls back on the desert land in a form of rainfall (Paton 2008).

This method of supply freshwater has been successful in countries located in arid regions of the world. For instance, countries such as Egypt, Eritrea, Tunisia, and Libya have large inland depressions, seawater greenhouses, which act as sources of freshwater for domestic uses and irrigation. Egypt is a very good example of a country, which depends on seawater greenhouses for supply of freshwater for irrigation purposes. Currently, Egypt is one of the largest importers of horticultural products in the African continent despite the fact that it is a desert country. It relies on seawater greenhouses for freshwater. It is therefore clear that this technology is very feasible and can be used by other desert countries.

According to Paton, there are around 200,000 hectares of land covered with seawater greenhouses in the Mediterranean region (2008). The Mediterranean region has been observed to be growing at a rate of 10 percent every year, since it started depending in seawater greenhouses for supply of freshwater. Before introduction of seawater greenhouses, many areas in the Mediterranean region suffered from water quality and availability issues. However, after the introduction of this technology, the situation has reversed and these areas are now practicing agriculture using freshwater supplied through the technology of seawater greenhouses. Example of these areas is Oman, and Abu Dhabi (Paton 2008).

Rainwater harvesting is yet another technology, which can act as a good source of freshwater for arid region of the world. Rainwater can be harvested in arid areas through construction of dams in the arid areas. These dams are constructed in such a way that during the rainy seasons, all runoff water passes through the dams’ catchment areas (Need for Desert Rainwater Harvesting 2010). The walls of the dam are covered with non-porous material to avoid absorption of the harvested water by the desert soil after the end of the rainy season. This method has been very feasible in various countries, which are located in arid and semi-arid areas.

A very good example is the Swami Madhavanand Lake (a surface dam) located in Rajasthan, a semi-arid areas in India (Need for Desert Rainwater Harvesting 2010). For a long time, Rajasthan had suffered from drought and lack of fresh water. Every time is rained, all the run off water would be washed down stream. Then after the end of the rainy seasons, people of Rajasthan would be left with no source of freshwater for domestic purposes as well as for irrigation. After the construction of the dam, the Rajasthan region has been having a constant supply of freshwater. Water from the dam is treated to make it safe for drinking. Water from the dam is also used in hospitals, and in farms. The prevalence of water related diseases has reduced in the Rajasthan region since the completion of the dam. This is because the locals no longer use unsafe water for drinking; instead, they rely on the harvested water in the dam for drinking and cooking (Need for Desert Rainwater Harvesting 2010).