Daily Times, January 18, 2006
World Bank report on Pakistan water resources: Water economy: running dry
Pakistan is one of the world’s most arid countries, with an average rainfall of under 240 mm a year. The population and the economy are heavily dependent on an annual influx into the Indus river system (including the Indus, Jhelum, Chenab, Ravi, Beas and Sutlej rivers) of about 180 billion cubic meters of water, that emanates from the neighbouring countries and is mostly derived from snow-melt in the Himalayas. Throughout history, people have adapted to the low and poorly distributed rainfall by either living along riverbanks or by careful husbanding and management of local water resources. One of the greatest of human civilisations – the Indus Valley civilisation (Harrapa and Mohenjo Daro) – flourished along the banks of the Indus.
This precarious, low-level balance between man and water was decisively shifted with the advent of large-scale irrigation technology in the 19th century. The Indus irrigation system became the largest contiguous irrigation system in the world. The desert literally bloomed, with irrigated agriculture providing the platform for the development of the modern economy of Pakistan.
This hydraulic economy has faced and surmounted three massive challenges in the last half century. The first challenge arose because the lines of Partition of the Indo-Pak sub-continent severed the irrigated heartland of Punjab from the life-giving waters of the Ravi, Beas and Sutlej rivers. In an unprecedented triumph of water diplomacy, Pakistani engineers, together with their Indian counterparts and the World Bank, negotiated the Indus Waters Treaty, giving Pakistan rights in perpetuity to the waters of the Indus, Jhelum and Chenab rivers, which comprise 75 percent of the flow of the whole Indus system.
The second challenge was that there was now a mismatch between the location of Pakistan’s water (in the western rivers) and the major irrigated area in the east. Again Pakistan’s water engineers were up to the task, building the world’s largest earth-fill dam, the Tarbela on the Indus, and link canals, which ran for hundreds of miles and carried flows ten times the flow of the Thames River. To a considerable degree (but not completely) the “heroic stage” of water engineering in Pakistan was now over – as in other countries the major challenges were now those of management. This is the case in all countries. But in the case of Pakistan, however, the “heroic” era had involved particularly blunt affronts to the living organism that the river represents. The natural flow regime was dramatically altered: rivers which had previously meandered over wide plains were now confined within narrow channels, sediments which had previously nourished the delta were trapped, vast quantities of water were disgorged onto deserts, substantial parts of which were of oceanic origin and highly saline. It was this last reality which gave rise to the third major challenge facing Pakistan shortly after Independence. Hundreds of billions of cubic meters of water were now stored in the naturally-deep aquifers of Punjab alone. In many areas water tables had reached the level of the land, giving rise to the twin curse of waterlogging and salinity.
In the early 1960s, it appeared that Pakistan was doomed, ironically, to a watery, salty grave. With equal doses of good thinking, good planning and good luck, this problem is now not beaten (nor will it ever be) but controlled and managed, to a degree that no one foresaw fifty years ago. The good thinking was the application of water science and economics by many of Pakistan’s best and brightest in conjunction with many of the best water minds in the world. The “solution” was not the obvious one of lining canals and putting less water on the land but of increasing the use of groundwater, thus both increasing evapotranspiration, drawing down the groundwater table and leaching much of the salts down and out of the root zone. The good thinking and good planning were classic “public goods”. The “good luck” driver of this revolution was the modest but transforming tubewell and diesel engine, bought and managed by millions of farmers for the simple reason that this decentralised “on-demand” source of water enabled them to greatly increase their crop yields and incomes.
So the modern history of water development and management in Pakistan is one in which the glass can be seen as more than half full. But, as this report will show, the glass can also be viewed as much more than half empty too. Once again, the survival of a modern and growing Pakistan is threatened by water.
The facts are stark.
For complete report, see:
http://www.dailytimes.com.pk/default.asp?page=2006\01\18\story_18-1-2006_pg7_27
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