What the Ancient Mariner expressed in frustration when they found themselves becalmed in the middle of ocean, as I understand it, running out of drinking water. But in this poem, what he said almost two centuries ago is certainly has relevance in real life today. The one of the most serious threats to humanity over the coming decades is the shortage of fresh clean water. Nowadays the earth is still rich in seawater, but fresh water is not. The global situation is less than 3% of the world’s water is fresh, the rest of them is seawater and undrinkable. So, the 7 billion population of the world must rely on this 0.5% of freshwater for all of man’s and ecosystem’s needs because of other 2.5% are frozen.
Source: Water Business Council for Sustainable Development (Fry, 2006)
With the global population is projected to increase about 9 billion by 2050, the World Bank forecasts the two-third of global population will run short of fresh drinking water by 2025. (Network, 2012). This means the water usage growing at more than twice the rate of global population growth. Scarcity of drinking water is already afflicting major problems for than a billion people, mostly in arid developing countries.
Fresh water is a renewable and changeable, but limited natural resource. Fresh water can only be renewed from through the process of water cycle but if the human activities consumed more than is restored by nature, the quantity of fresh water is reduced. Therefore, the challenge is to get the freshwater to the right place and in the right quantities. However, all form of water processing requires energy, so an increased demand for water will inevitably require more energy. With some of the engineering development use of improved technology by few countries to produce a better water-resource management and is certainly part of the answer and bring sign of hope.
In the 21st century, some countries use desalination to create pure water but this process is energy intensive and expensive. The best example is the...