Only one per cent of total water on earth is available for consumption. About five billion people on earth are experiencing water scarcity of various extents. On average basis daily 2000-3000 liters of water is required to meet the dietary demand of one inhabitant on earth.
Per capita availability of water in Pakistan is about 1420 m3 and has been declared water scare country by UN. About 88 per cent of water supplied to big cities is unfit for human consumption. There is a need for proper policies and their implementation by having a glance on present and future challenges.
Collection of water sources that are either useful or potentially useful are termed as resources of water. The most common sectors of water usage are agriculture, industry, household and recreation purposes. About 97 per cent of water on earth is unfit for consumption; out of the remaining around two parts are in frozen form, In short only one per cent of total water present on earth is consumable. Common sources of water are surface/subsurface water, water obtained from desalination and from the melting frozen resources.
Agriculture sector consumes largest (70 per cent) portion of water worldwide and according to various studies, it was concluded that on average basis daily 2000 to 3000 liters of water is required to meet the dietary demand of one inhabitant on earth. Around 50 years ago water was not among the hot issues in the world, where the consumption of water was 3 times less than that at present. With the increase in population, the demand for water increased especially for agriculture and industry. In future the water requirement would be much more but the resources are same and continuously depleting.
Another vital reason is the climate change due to which the total amount of available freshwater supply is decreasing. Climate change has caused receding glaciers, reduced stream and river flow, and shrinking lakes and ponds. Many aquifers have been over-pumped and are not recharging quickly. Although the total fresh water supply is not used up, much has become polluted, salted, unsuitable or otherwise unavailable for drinking, industry and agriculture. Due to the change in climate, among the other most important aspects are uncertainty about the floods and drought periods.
Water pollution is also among the highlighted issues. At one part where we have limited water resources and on other side we are also polluting those resources either through agriculture, household or from industrial sources. Some countries in the world, for example Sudan, Venezuela, Ethiopia, Tunisia and Cuba have significant population but the only contaminated water is available for consumption.
According to a report published in 2007 by the International Water Management Institute about five billion inhabitants on earth out of 7 billion are experiencing water scarcity of various extents and around 99 per cent problem exists in developing countries. However, scientists are developing new technologies for the efficient use of water, specially focusing on agriculture and industrial sector.
It has been predicted that future wars would be for water than any other issue. Some of the famous quotes are; The next war in the Middle East will be fought over water, not politics (Boutrous Ghali), Fierce competition for fresh water may well become a source of conflicts and war in future (Kofi Annan), Wars of next century will be over water unless significant changes in governance occurred (Ismail Serageldin).
Pakistan has been declared among the water deficient countries, according to the UN repot. Himalayan glaciers are the largest source of water in Asia. It has also been stated by the UN climate report that in next two centuries the largest source of water (Hamalian glaciers) are expected to be completely exhausted. It was also reported that Pakistan is expected to experience floods followed by droughts in coming decades. In another report by UN, the country having per capita income of water less than 1000 cubic meters per person per year was declared the title of country facing “water scarcity”, while according to a report published in 2005, the per capita income of water in Pakistan was about 1420 cubic meters per person. The annual growth rate of tube-wells is around 7 to 8 per cent, but most contain saline water (36 per cent ground water) that is further deteriorating our land resources.
In Pakistan, agriculture sector consumes largest portion (96 per cent) of water. Despite of so much consumption of water, a large area of the country is still uncultivated due to the non-availability of good quality irrigation water, while the use of water efficient technologies is also very rare. Mostly people consume (32 per cent) tap water for drinking purposes and the use of hand pump driven water (28 per cent) is also very common. It was revealed in 2012 by the Pakistan Council of Research on Water Resources that around 88 per cent of water supplied in big cities is unfit for drinking purposes because of the microbial contaminations. Apart from microbial contamination, the concentration of heavy metals was also significantly higher in more than 80 per cent of the water samples. However, the initiative for the provision of drinking water has been taken with the name of “Clean Drinking Water Initiative” under the Umbrella of US AID, but the progress rate is very slow and has been initiated only in big cities.
It is not possible to depict the full resource and utilization of water in the world as well as Pakistan, however, it makes clear from statistical data that we are facing water scarcity. Thus, there is a need for proper policies and their implementation at national and international level by having a glance on present and future challenges.
Short Link: http://technologytimes.pk/post.php?id=5429