By : Saba Irum
Pakistan is an agricultural country. Therefore water is an essential resource for sustained economic growth as well as human survival. Water, which is one of the most important national resource is increasingly becoming a scarce natural resource. Presently agriculture sector is using 93%, domestic sector 5% and industrial sector 2% of water resources. The domestic and industrial sector water uses are projected to increase to 15% by 2025. Agriculture sector is the major user of water, but its share is expected to decrease because of competing nonagricultural demands. Our Indus Basin Irrigation System (IBIS) is the world’s largest contiguous irrigation system. It comprised three large dams, 85 small dams, 19 barrages, 12 inter-river link canals and 45 canal commands. This irrigation network is the biggest infrastructure asset of Pakistan worth approximately US$ 300 billion of investment.
Water resources are inextricably linked with climate; hence, the projected climate change has serious implications for Pakistan’s water resources. The freshwater resources in Pakistan are mainly based on snow and glacier melt and monsoon rains, both being highly sensitive to change. The average annual flow of IRS is around 142 million acre-feet of which 104 MAF is diverted to the canal network, while major portion of the remaining balance of around 35 MAF outflows to the sea. Fortunately Pakistan has a large useable groundwater aquifer, God gifted natural reservoir, which is largely recharged from the surface flows and rains. This resource is being exploited heavily and particularly in some hyper-arid areas to the extent of criminality. Pakistan has moved from a water affluent country to water stressed country. In 1947, per capita water availability was 5000 cubic meter, which has currently decreased to around 1000 cubic meter, and projected to decrease to 800 cubic meter per capita by the year 2025.
There are five major rivers (Jhelum, Ravi, Beas, Sutlej, and Chenab) .The three minor rivers (Haro, Soan, and Siran), which make up the embryonic Indus river system, is the main source of surface water in Pakistan, along with the dams. Major Dams are Tarbela and Mangla, with Bhasha under the way .G glaciers in Pakistan cover 13,680 sq. km which is 13% of mountain regions of the Upper Indus Basin (UIB). Melt water from these Glaciers contributes more than 60% to the flows from UIB.International Commission for Snow and Ice (ICSI) “ (1999): Glaciers in Himalayas are receding faster than in any other part of the world and, if the present rate continue, the likelihood of them disappearing by the year 2035 is very high”. Hewitt (2005): reported widespread evidence of glacier expansion in the late 1990s in the Central Karakoram, in contrast to a worldwide decline of mountain glaciers Some Projected Changes in River Flows due to Melting of HKH Glaciers (As reported in recent studies) World Bank (2006): Western Himalayan glaciers will retreat for the next 50 years causing increase of Indus River flows. Then the glacier reservoirs will be empty, resulting in decrease of flows by up to 30% to 40% over the subsequent fifty years.IPCC AR4 (2007): Glacier melt in the Himalayas is projected to increase flooding within next two to three decades. This will be followed by decreased river flows as the glaciers recede. These conflicting findings make the impact of climate change on Karakoram glaciers and Indus River flows very uncertain. Freshwater availability is also projected to decrease which will lead to biodiversity loss and reduce availability of freshwater for the population.
Pakistan is at greatest risk due to increased flooding from the rivers and in some cases sea. Being a predominantly agriculture economy, climate change is estimated to decrease crop yields in Pakistan which in turn will affect livelihoods and food production.
Pakistan’s economy has been crippled heavily by devastating and repetitive floods during the last decade. In the past 10 years, Pakistan has been hit by floods almost every year. However, the floods of 2010 and 2011 have emerged as the biggest catastrophes in the country’s history.
The flood of 2010 remains as one of the biggest tragedies in the world’s history, with 20 million people affected by it. The floods resulted in approximately 1,781 deaths, injured 2,966 people and destroyed more than 1.89 million .The 2011 floods also wrecked havoc , and affected 5.3 million people and 1.2 million homes in Sindh, as well as inundating 1.7 million acres of arable land. 2010 WHO Report… Total 5.3 million consultations were reported in the country.708, 891 individuals (15% of the total population) were reported with acute diarrhoea.A Drought is a period of abnormally dry weather due to the lack of Rainfall. The chief characteristic of a drought is a decrease of water.Availability in a particular period and over a particular are Pakistan’s economy has been punched heavily by the continuous spell of droughts for the last many years, particularly in the provinces of Baluchistan and Sind. Drought in these areas has reduced the river flows, resulting in drying up of the irrigation canals, leading to a severe agricultural deprivation. The increased temperatures because of the increased GHGs as well as a mismanagement of the water reservoirs need to be blamed for the condition.
The availability of fresh water is mostly affected by a change in climate.The water resources of Pakistan are scarce which directly related to food insecurity, especially in rural areas. The arid and semi arid zones are the most vulnerable to climate change as these regions are already facing water shortage and high temperature. The recent studies indicate that Pakistan’s 22.8% land and 49.6% population is at risk due to impacts of climate change. The diseases which are transmitted by vectors for example malaria, dengue ,cholera etc that are already cause of low morality rate in Pakistan are climate sensitive. Climate change scenarios have resulted in an increase in the epidemic potential for 12-27% for malaria and 31-47 % of Pakistan may run dry by 2025: Pakistan touched the water stress line in 1990 and crossed the water scarcity line in 2005.If this situation continues, then chances are high the country will face acute water storage or drought like situation in near the future. Despite the warnings , the general population thinks that authorities do not seem to take water insecurity seriously. That is good initiative to construct the under ground water tank by WASA in Rawalpindi to store rain water the during monsoon season that also help to maintain the water table in city to resolve water shortage problem . The government should form dams as soon as possible to store fresh water.