By- Naseem Sheikh
Asia, located primarily in the eastern and northern hemispheres, is the world’s largest and most populous continent, Population of Asia 2011 is 3,879,000,000 (3.8 billion). It covers 8.6% of the Earth’s total surface area (or 29.9% of its land area) and with approximately 4 billion people, it hosts 60% of the world’s current human population, But only about 36 percent of the renewable fresh water. So, even on a continental scale, it is clear that water is a serious constraint in Asia. China, India and Pakistan are three of the four top irrigators in the world, suffering with serious water problems.
Pakistan has in most areas of agriculture a monsoon climate, and there might be abundant rainfall during the wet season and then a very long dry season where crop production depends very heavily on irrigation water. Groundwater is a very important source of irrigation for farmers. Ground water is being over-pumped extensively in order to meet current demands for food production but if our demands exceed that renewable supply, then we must be in the situation that we might be over-pumping groundwater to satisfy the demand, or taking too much water from river basin systems, result in formation of salinity and barren land that in long run cause food scarcity. Over-pumping of groundwater for agriculture, industry or domestic use comes at a sharp ecological price. It disrupts the natural hydrologic cycle, Causes Rivers and wetlands to dry up, the ground to collapse and fish and wildlife and trees to die.
Water and agricultural sectors are likely to be the most sensitive to climate change. Fresh water availability is expected to be highly vulnerable to the anticipated climate change. While the frequency and severity of floods would eventually increase in river deltas. The arid and semi-arid regions could experience severe water stress.
According to an estimate today 1.2 billion people lack safe drinking water and 2.4 billion lack access to basic sanitation. United Nations officials say that if we continue with business as usual, two-thirds of the world’s population will be living in moderate to severe water stress by 2025. More than two billion people worldwide live in regions facing water scarcityand in Pakistan this is a particularly acute crisis. Millions of Pakistanis currently lack access to clean drinking water, and the situation is only getting worse. Pakistan has approximately 35 million acres (140,000 km2) of arable land irrigated by canals and tube wells, mostly using water from the Indus River.
Pakistan luckily had the largest irrigation system, but water losses from the system were the highest in the World, due to which its agricultural sector have been affecting badly as population of country increasing rapidly but as compare to population growing capacity of agricultural sectors reducing rapidly due to water shortage. Timber mafia and rapid industrialization are also playing important role in reduction of agricultural sector. Chashma, Mangla, and Tarbela are mainly use for irrigation purposes but the gross capacity of these dams has decreased because of sedimentation, a continual process. Per-capita surface-water availability for irrigation was 5,260 cubic meters per year in 1951. This has been reduced to a mere 1,100 cubic meters per year in 2006. The water shortage will cause a wheat deficit of 12 million tons per year by 2012–13.
Fig: Fresh water withdrawal in different sectors of Pakistan
NO doubt Pakistan’s water crisis is predominantly a manmade problem. Pakistan’s climate is not particularly dry in fact semi arid to arid, nor is it lacking in rivers and groundwater. Extremely poor management, unclear laws, government corruption, and industrial and human waste have caused this water supply crunch and rendered what water is available practically useless due to the huge quantity of pollution.
According g to World Bank report of 2006 Pakistan was fast moving from being a water-stressed country to a water-scarce country, primarily because of its high population growth, over-exploitation of ground water, pollution, poor repair in water infrastructures and financially no sustainability of water management system. Interestingly, the country’s large parts have good soil, sunshine and excellent farmers and these can get much more value from the existing flows.
The most water- rich country in terms of the run-off from rain-fall to population is Iceland, with more than 500,000 cubic meters per person per year; the most water- poor are Egypt, with just 0.02 cubic meters. Water is absolutely essential for plant life. It is pertinent to mention here that the major source of drinking water in Pakistan is groundwater, so water availability is the second most serious issue.
Future water demand will be affected by many factors, including population growth, wealth and sharing. Globally, it is estimated that between half a billion and almost two billion people are already under high water stress, and this number is expected to increase significantly by 2025, due primarily to population growth and increasing to climate change.
We live in an agricultural region water is key for survival, water lost through mismanagement mainly. A big investment in the repair of existing dams and the large scale construction of new water storage is simple solution of problem. In managing water resources, the Pakistani government must balance competing demands between urban and rural, rich and poor, the economy and the environment. However, because people have triggered this crisis, by changing their actions they have the power to prevent water scarcity from devastating Pakistan’s population, agriculture, and economy.