Water sustains and regulates life. Almost all the terrestrial processes require water for their successful completion. Pakistan is the world’s fourth largest consumer of water, while it stands first globally, when it comes to the water use per unit GDP. Almost all the surface water supplies of the country are used for agricultural and power generation purposes.
Agriculture, the backbone of Pakistan economy, which contributes 19.8 percent to GDP and provides employment to 42.3 % of the country’s workforce, chiefly relies on water. The water requirements of a large portion of the county’s agricultural land are fulfilled by Indus river system. The rest of the cultivated land is either rain fed, irrigated through tube wells or rodkohi system. According to agricultural statistics of Pakistan, the total irrigated area of Pakistan is 18.63 million hectares. About 77 percent of the total irrigated area belongs to Punjab, 11 percent to Sindh, 5 percent to KP and 6 percent to Baluchistan.
Among the emerging threats to the country, the most alarming is that of water scarcity. According to IMF, Pakistan is the third most water-stressed country in the world. It has crossed the water stress and scarcity lines in 1990 and 2005, respectively. Currently, the country’s per capita annual water availability stands at 1017 cubic meter which was about 1282 cubic meter in 2002. With the present pace, the gap between demand and supply will reach 83 MAF by 2025 (IMF). The Indus basin aquifer, which is the country’s largest source of agriculture water, is ranked as the world’s second most overstressed aquifer among the list of 37 largest aquifers analyzed by NASA between 2003 and 2013.
It is not only affecting agriculture but also the other sectors including power and industry. The drastic changes in the country’s hydel power, which is 30 percent of the total production, can exacerbate the situation of complicated power shortfall. The agriculture sector, which consumes 12 percent of the national power, can further be troubled by this shortfall.
Among the major reasons, which contribute to the growing water scarcity in Pakistan, is the lack of sufficient storage structures. According to a study, the country needs one major dam during each 10 years for the effective control of recurring floods and conservation of water. Unfortunately, In Pakistan, no major dam has been constructed since 1970s. Kalabagh dam, which is the need of the hour, still lies in controversy. The current annual flow through the country is 169 MAF, for which the installed capacity of major reservoirs (Tarbela and Mangla) is only 18.5 MAF. Not only the capacity, but the storage duration of 30 days is also problematic against the international standard of 120 days.
Of the other reasons contributing to water scarcity, siltation is of prime importance. The country’s major reservoirs have lost about 25% of their capacity due to heavy sedimentation. This reduction in capacity has further reinforced the wastage of water.
In recent past, climate change has gained pace which has predominantly affected Himalayan glaciers and hence, the level of water in Indus river system. It has drastically changed the rainfall pattern, which is resulting in floods and wastage of water.
Groundwater pumping is another reason which adds insult to the injury. According to Planning and Development Division, the annual groundwater pumping through the countywide 954320 tube wells is 50.21 MAF. On the contrary, annual recharge to the groundwater in Pakistan is 40-45 MAF. This discharge-recharge difference is continuously destabilizing and lowering the water table down. Our country lacks the basic framework to regulate and manage groundwater and therefore, the water table is lowering at the rate of 1-10 feet per annum without any resistance.
Due to the rapidly growing population, forests are being cut down faster and arable land is converting into urbanized land and pavements. These factors decrease soil infiltration and result in increased runoff which leaves the soil eroded and a large quantity of water is lost to floods. After the conclusion of Indus Water Treaty in 1960, India has several times violated the provisions of the treaty by initiating projects like; Wullar barrage, Kishanganga and Baghlihar dam. These projects have not only affected the water availability for agriculture but have also interfered with the power production of Pakistan. It has been reported that Kishanganga project will decrease the power production of the under construction Neelam-Jehlam hydro power project by 9 percent.
In Pakistan, majority of canals, leading water to the fields, are either unlined or poorly lined. Therefore, a large quantity of irrigation water is seeped through the bottom and banks of canals before being conveyed to the fields. The farmers in Pakistan mostly apply old and conventional irrigation methods which not only results in water wastage but also in increased growth of weeds and pests. Unlike drip and sprinkle irrigation, conventional methods over irrigate the field and decrease the application efficiency, as most of the water is lost to deep percolation, evaporation, overtopping and seepage. The field application efficiencies of different irrigation methods are: surface (60%), drip (90%) and sprinkle (75%).
It has been estimated that about 75 percent of the annual rainwater is lost to floods during the three months of monsoon rains. There are very less structures in our country to store this water. Certain structures like check dams and canal diversions can be used to save this water and increase recharge to the groundwater. Moreover, using the practice of rainwater harvesting, this water can be used later. Canal water is greatly underpriced in Pakistan and the government is recovering only one-fourth of the maintenance and operation costs from the public (IMF). Tempted by the low price of water, farmers usually over irrigate their fields. Moreover, farmers are unaware of the damages they are doing to their fields and nation through overuse of water.
The cropping system of Pakistan mostly consists of crops that have high water requirements like sugarcane, rice, maize, vegetables and beans. These crops are very sensitive to water shortage, and therefore frequently irrigated which further worsens the situation. The government must turn an attentive eye to the issue at an urgent basis because, according to PCRWR, the country may run dry by 2025. An extensive water conservation network is the need of the hour to ensure efficient and sustainable use of water. Any delay in this regard will push the country towards a catastrophe like Sana’a where the water table is 1200 meter deep.
n The writer is a freelance columnist.