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Lynch: A few hours drive from Karachi, in southern Pakistan, the first sight of what used to be one of the world's great rivers is jarringï¿½ From a bridge above the Indus, Mohammed Tahir Quereshi points to a vista dominated not by waterï¿½ but by sand.
Quereshi: ï¿½The sand dunes, they are extending right from the upper stream to the Arabian Sea.
Lynch: ï¿½So the mighty Indus river is mighty no more?ï¿½
Quereshi: ï¿½Absolutely, it's not a river, it's a small canalï¿½ï¿½
Lynch: Quereshi is a coastal ecosytems director with the International Union for the Conservation of Natureï¿½ He says the river used to span five kilometres here - now it's barely 200 meters wide. And as the Indus has dried up, it has taken people's livelihoods with it.
On the sandy banks of the Indus near the village of Darwish, a man stacks firewood cut from nearby trees onto a donkey cart. Firewood has replaced fish and produce as the main harvest here now. On the sand, discarded fishing nets lie in piles. They are relics of a time Gul Mohammed wishes would return.
Mohammed: ï¿½About one in four people here are left, the rest have gone to find work in the city. There was a time when we had so much help we could fill up our Datsun truck full of fish. Today, the fishermen cut wood - they can't find fish.ï¿½
Lynch: Mohammed also used to grow bananas nearby.
But the river has dropped so far, he can't use his irrigation pump. It's a familiar problem that's affected the lower reaches of once-great rivers around the world.
Gul Mohammed with defunct water pumpGul Mohammed with defunct water pump
As Pakistan's population has grown, so has the demand for water. Huge volumes of water are drawn off upstream-mostly for agriculture, but also for Pakistan's booming cities. And people downstream are left with nothing.
In the tiny town of Kati Bundar, water drips from a tanker truck onto the street. Mohammed Ismail Mehman has lived here all his life.
Mehman: ï¿½All our lands are lying useless because of brackish water. Hundreds of thousands of acres of land is useless.ï¿½
Lynch: Mehman says people here used to use Indus river water to grow coconuts and grapes. Now they have to pay for their water, from the truck.
Managing a finite water supply in a country with a rapidly growing population has long been a challenge here. Agriculture accounts for a quarter of Pakistan's GDP. 70%
of the population are involved in farming. And Pakistan remains a poor country. But Fazalullah Quereshi believes that the government could do more to protect the Indus.
Quereshi spent 36 years as a top bureaucrat, urging politicians to tackle the growing problem. He's heard all sorts of excuses.
Quereshi: ï¿½And when they say there's no funds, I don't believe because I've handled budgets for twenty years. If there's a will, there's a way.ï¿½
Lynch: Pakistan has a vast irrigation system - one of the biggest in the world. But it loses huge amounts of water to evaporation and seepage. Quereshi and others say the government should get rid of such things as irrigation canals and replace them with much more efficient drip or sprinkler systems similar to what Israel uses. At the very least, Quereshi says the canals should be lined with concrete to prevent waterlogging. He believes such changes could bring big benefits to a land choked by poverty.
Quereshi: ï¿½Because if you manage water and land properly you can engage more people in that sector and you can grow more you can export more and that can generate more funds for the country for the people and more investments. So there's a whole cycle will run.ï¿½
Lynch: Pakistan's water minister declined requests to be interviewed. The government has plans to improve irrigation practices, build more dams and to do a better job of conserving water. But a recent World Bank report says the Pakistani government itself is concerned about its ability to carry out large-scale projects.
And others also despair of change coming anytime soon. Dr. Abdul Majeed of the Pakistan Council for Research in Water Resources says many of the country's powerful politicians have no incentive to push for a real overhaul of farming practices.
Majeed: ï¿½All these politicians are generally big landlords who own acres and hundreds of thousands of acres of land, and water is the major input in getting the agriculture from these lands. So they have their own interest and that creates problems.ï¿½
Lynch: And Dr. Majeed believes that in an already volatile country, the situation is potentially explosive.
Majeed: ï¿½You know, if you deprive one farmer of his livelihood it's a dangerous sign. How he's going to meet the requirements of his familyï¿½ so this situation one can imagine it will not only become alarming. It will become dangerous as well, people fighting with each other, people fighting with the government.ï¿½
Lynch: There is another concern, though not one people talk about readily. The Indus has its headwaters far away in the Tibetan plateau - it then runs through Indian controlled Kashmir, before flowing through Pakistan on its way to the Arabian Sea.
India and Pakistan have signed a treaty that allocates shares of the Indus and other rivers. But Pakistan has sometimes complained that India is cheating - something India denies. Climate change could also seriously affect the flow of water into the Indus. Fazalullah Quereshi, the former water bureaucrat, worries that if the water shortage grows worse, it could lead to a wider conflict with India.
Quereshi: ï¿½It is one of the reason Pakistan wants Kashmir issue to be settled in a way so at least we can protect our lifeline.ï¿½
Lynch: In the Indus delta town of Kati Bundar, a fisherman gets ready to head out. Locals have lost the fish and shrimp they used to catch when the river disappeared. But the sea still holds crab - so that's the main catch now. There are more problems besetting the town. As the Indus has disappeared, so has the silt it used to carry to the deltaï¿½ without it, the sea is licking away at the land and flooding is increasing. Mohammed Ismail Mehman has watched his town shrink from 15 thousand residents to only three thousand. Mehman talks of the hardship.
Mehman: ï¿½Fishing and farming is all people here have really ever known, now they can barely make a living.ï¿½
Lynch: For thousands of years, water has been a lifeline for people here and across Pakistan. But increasingly, the source of their livelihood is becoming the source of conflict. There are growing protests by fishermen and farmers. And last year's World Bank report warned that increased social discontent over water shortages could threaten the very viability of Pakistan as an independent nation.
For the World, I'm Laura Lynch on the Indus River delta in Pakistan.