The Challenge Of Sustainable Water Supply

Desalination is basically the procedure of separating excess sodium chloride, minerals and impurities from sea and ocean water to make it usable for irrigation and human consumption. It has been touted to rid the world of its current water problems for nearly 5 decades now, during this period huge strides have been made in the desalination technology. These advances have made it possible to venture into desalination as the long term option to the water problem in many parts of the world. It is seen as long term since the ocean is not going anywhere anytime soon as compared to lakes and rivers that have been going dry seasonally. The state of California is not new to the water shortage problem; as stated above tit has been a witness to previous droughts. It is therefore time to consider a long term solution to this problem.

One solution to droughts is desalinization. Desalinization is, “the process that separates most of the dissolved chemical elements to produce water that is safe to drink” (Land and Water 4). This process costs a lot of money, which makes it harder to do. There are many problems with desalinization such as, using a very big amount of

Desalination is one of the more popular options being considered to attempt to terminate the drought. Desalination is a process through which salt water is pumped from the ocean in to a treatment facility, and then the salt is extracted to make it possible to be used domestically. This is a long drawn out process, which involves seven different steps. The steps of desalination include the

Desalinated water is critical to Perth’s water supply as Western Australia continues to experience a drying, arid climate. It is important that a reliance on traditional water sources such as dams are reviewed and new and sustainable sources that are climate independent are implemented. Factors of a drying climate, extreme weather conditions, population increase (Population in Perth to double in the next 50 years) and the way we currently source out water need to be evaluated in order to ensure a climate resilient supply that is independent of varied amounts of rainfall. Desalinated water is critical to Perth’s water supply due to the states large infrastructure and mining industry.

Last century, the population of California was increasing quickly. However, the water distribution of California is unbalanced, for the southern part has fewer rivers and lakes, but has more deserts comparing with northern regions. Therefore, many constructions have been built to transport (which uses 19 percent of state’s overall electricity, 32 percent of its natural gas, and 88 million gallons of diesel per year ) and store water. From then on, each time drought happens, the government will control the transportation of water, limit the provision of the northern region and supply more to the southern area. The extra part of the water will be stored in reservoirs. Today we are facing one of the most serious droughts, and up to now, the government has reduced 28 percent of residential water, storage 1.6 million acre feet water which is enough for eight million people using one year.

Among all sectors in Egypt, agriculture consumes the largest budget of available water supplies, with its share exceeding 80% of the total gross demand for water. In case the actual consumption of water is considered (water supply minus the water that is returned to the system), the share of agricultural demands is even higher at more than 95%. The area of cultivated land raised from 5.8 Million fed. in 1980 to about 8.0 Million fed. in 1997. Therefore, the consumptive use of water in agriculture has been steadily increased from an estimated 29.4 BCM/yr. to 38.5 BCM/yr. during the same period (1980-1997). This increase has been made possible by an increase in agricultural drainage water reuse, the abstraction of groundwater and a decrease in the fresh water outflow to the sea. In 1997, the total amount of diverted water for irrigation was 57.8 BCM/yr, (MWRI 2005). In 2010, the total agricultural withdrawal was accounted at 67.0 BCM (about 86% of available water supply), (AusAID 2011). Any water becoming additionally available will primarily be used to irrigate new development areas and not to increase the supply to existing lands. Based on water inflow of 55.5 BCM/year, it is expected that by the year 2017 agricultural lands will cover about 11 million fed., and 63.6 BCM of water will be allocated for agriculture. The total agricultural water consumption in 2017 is estimated at 38.7

However, the process of desalination is not easy to do on a large scale in underdeveloped areas due to the cost of the energy input, as well as taking into account the environmental issues alongside it. Desalination is a difficult process to do inland, partly for accessing the water, which would have to be obtained from aquifers (Elsaid et al., 2012) and partly for having to dispose of the brine. Therefore, it is a process which is mainly found in coastal areas.

A major problem for human populations in semi-arid environments is the lack of water for domestic consumption. On average a person needs 200 liters of water (Heller and Padua, 2006) per day to meet their basic needs (food and drink). This volume of water per person is very difficult to be obtained in environments where the average annual rainfall is low, less than 800 mm, a value which characterizes the semi-arid environment (MI, 2005). This difficulty is even more important when considering that the rivers that exist in these environments are not permanent, but go through periods without flow and occurrence of a dry period is greater than probability of 60% (MI, 2005) .

Water is the main source of life on the Earth. It is vital for normal existence and functioning of organisms. Earth is sometimes called “water planet.” But, in fact, the number of freshwater is limited. “Only about 2 percent of the planet's water is fresh.” (How much water is there on Earth?) This water is not enough even to meet daily needs of mankind. According to World Health Organization, “a lack of water to meet daily needs is a reality today for one in three people around the world.” (2009) In the Middle East the situation is especially hard. This region is thought to be one of the droughtiest places in the world, most of it’s territory is deserted. Freshwater accounts to 1 percent of the world’s supplies, while the population comes

Nearly 1.2 billion people worldwide lack access to a safe water supply, almost 2.5 billion people cannot access basic sanitation which caused the deaths of More than five million people who die each year from water-related diseases that are mostly preventable (IHP,2005). Some areas of our world are more affected by the lack of fresh water supply than others, those are considered as Arid regions. Arid and semi-arid regions are characterized by low erratic rainfall of up to 700mm per year, repetitive droughts and different combinations of vegetative cover and soils which are not suitable for cultivation

Australia, as the driest inhabited continent, had installed 331 desalination plants supplying high quality water to the increasing population. Another country, China, also implete the use of desalination plants to tackle the drought and large population problems. This section will compare several technologies used in these two countries. As shown in Table 1, RO is the most used technology in both countries, accounting for 61.03% in Australia and 81.3% in China.

Therefore, it would be an advisable solution to desalinate seawater in areas of drought. This method is widely used only in countries which are situated on islands or having access to seawater. For instance, the largest desalination plant in the world is in the United Arab Emirates. Jebel Ali is capable of desalinating 300 million cubic meters of water per year. ( Desalination n.d)

Abstract: Life on our planet requires fresh water. According to WHO, water scarcity affects roughly one-third of the world’s population, and approximately 2.3 billion people. The World Water Council states that this water crisis will become more acute over the next fifty years as the world population increases. Yet, water covers nearly three quarters of our planet -- 97.5% of this water is saltwater. Therefore, a practical, economically viable desalination process is crucial to overcoming this crisis. A number of seawater desalination technologies have been developed during the last several decades to augment the supply of water in arid regions of the world. Due to the constraints of high desalination costs, many countries are unable to afford these technologies as a fresh water resource. However, the steady increasing usage of seawater desalination has demonstrated that seawater desalination is a feasible water resource free from the variations in rainfall. A seawater desalination process separates saline seawater into two streams: a fresh water stream containing a low

Water is a natural resource of planet Earth, and affects all natural, social and economic systems. As recognized by the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) in 2007, observational evidence from all continents and most oceans shows that many natural systems, on which the hydrological cycle and therefore water availability, water quality, and water services depend, are affected by changing climate. As a result, this will also have major effects on human security and sustainable development.

Groundwater recharge is the process of water movement downward through a saturated zone under the force of gravity or in a direction determined by a hydraulic condition (Simmers, 1997). Natural recharge of groundwater may occur from precipitation, from rivers and canals, or from lakes. In arid and semi-arid areas, assessment of groundwater recharge is one of the key challenges in determining the sustainable yield of aquifers, as recharge rates are generally low in comparison with average annual rainfall or