God has blessed Pakistan with water resources, with water flowing down the Himalayas and Karakorum heights, the worlds largest glaciers, a free and unique bounty of nature for this land of alluvial plains. Earths total surface area (29.9 per cent of its land area) it hosts 60 per cent of the worlds current human population, but only about 36 per cent 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 irrigating states in the world, confronting 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 the current demands for food production but if our demands exceed that renewable supply, then we must be in a 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.
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. 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 the country increasing rapidly but as compare to population growing capacity of agricultural sectors reducing rapidly due to water shortage.
Chashma, Mangla and Tarbela are mainly used for irrigation purposes but the gross capacity of these dams has decreased because of sedimentation – a continual process. The water shortage will cause a wheat deficit of 13 million tons per year by 2013-14. Pakistan had around 5,000 m3 per capita per year of freshwater resources. The mismanagement of water will have its biggest impact on Pakistans agricultural sector. This prosperous industry relies on the single largest contiguous irrigation system in the world. While this is an impressive feat, Pakistan also fosters one of the lowest crop yields per unit of water in the world. This is alarming because Pakistan uses a whopping 97 per cent of its water resources on its agriculture industry, 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.
The most water-rich country in terms of the run-off from rain-fall to population is Iceland. The most water poor state is 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, primarily due to population growth and 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 Pakistans population, agriculture, and economy.
The situation in Pakistan seems grim, but there are steps that can be taken towards ensuring water security. One proposed method is to introduce water usage fees, especially for those who use irrigation to water their crops. Implementing a proper pricing system will not only raise revenue for maintenance and repair of irrigation infrastructure, but it will also make large landowners think twice before they waste water. This market oriented system can also work in urban areas. Another solution involves the introduction of better technologies to small farmers. Increasing the use of inputs such as fertilizers, hybrid seeds, and modern farming equipment can raise crop yields while making the most out of each drop of water used.
A “crop-per-drop” structure is especially useful in Pakistan, where most of the land is arid and must be irrigated. Cutting down inefficiency and waste is paramount to a sustainable agricultural system in such a climate. The use of drip irrigation technology to increase water efficiency. Put simply, drip irrigation slowly introduces water directly to plant roots through a system of pipes and valves. For most of Pakistans history, the response to water shortages has always been to build dams, redirect rivers, and irrigate the soil. While this may have worked in the past, this engineering-based approach largely ignores the reality that Pakistan is sitting on dwindling reserves.
The approach for the coming century must focus on re-education and conservation. Instead of thinking about how and where to build new dams, Pakistan should be thinking about how it can reduce waste in the existing system. Instead of figuring out ways to extract more water from the ground, Pakistan should be figuring out how to recycle its water and make the most of each drop. In a country that has the largest contiguous irrigation system in the world, the main obstacle is not that the system is not large enough, but that it has not been streamlined for efficiency. Pakistans water issues are multi-dimensional. There is no single, all-encompassing problem, but instead multiple, interrelated problems. Therefore, Pakistan needs to completely rethink its entire approach to its water resources. It will take time to implement solutions to these problems and yet time is in very short supply. It is projected that by about 2035, Pakistan will become water scarce.
The authors are from the Institute of Horticultural Sciences, University of Agricultural Faisalabad.