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In the windswept plateaus of northern Iraq, unseen aqueducts which have channelled water to arid settlements for centuries are running dry. Experts say the wide-scale demise of these ancient water systems is an ominous sign of how scarce water in the region will soon become, and the humanitarian disasters that could follow.
For villagers here, tragic consequences have already arrived.
Farez Abdulrahman Ali strides across a muddy field and sweeps a burly arm towards the mountains that loom over Shekh Mamudian village in the wilds of Iraq’s semi-autonomous Kurdistan region. This is the rugged terrain of the peshmerga , the Kurdish military whose name means "those who face death".
Ali explains that a subterranean canal - known in Iraq as a karez - once brought water to the village, where it gushed from a rock-lined tunnel into a pool just below the entrance to the local mosque. From there, it was channelled to nearby fields of okra, eggplant, onion and tobacco.
"Farmers would use the water," said Ali. "On hot days, children would play in the water. In the evenings, people would gather at the karez to talk about village things."
"The karez dates back to the time when karez were dug," he added, matter-of-factly. "Nobody in the village knows when it was dug. Even my grandfather doesn't know. It is probably 800 or 900 or 1,000 years old."
In autumn 2011, for the first time in the village's collective memory, the karez in Shekh Mamudian went dry. As the village chief, or mukhtar , Ali sees the loss of the karez as catastrophic for the livestock and crops the village depends on for its hard won self-sufficiency. Unless it is restored, he fears for the end of a community that withstood assaults by Saddam Hussein’s army in the 1980s, and survived as a bloody no-man's land in the Kurdish civil war of the mid-1990s.
"The karez was the source of life," Ali said. "The village now feels like a family that has lost its father."
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Echoes of Ali’s lament are being heard throughout the arid mountains and plains of Kurdistan, where the widespread demise of karez is becoming a humanitarian nightmare.
Last year, an inventory of karez systems in Kurdistan - believed to be the first such compiled in modern times - found that decades of war and years of grinding drought, combined with neglect and over-pumping from nearby mechanised wells, had brought these vital water lifelines to the edge of extinction.
According to a UNESCO report , just 116 of the 683 karez networks located in northern Iraq were still supplying water as of August 2009. As many as 40 per cent of the region's karez have dried up in the past four years alone.
Since 2005, more than 100,000 people have been forced to abandon their homes because their karez stopped flowing, and a further 36,000 are at immediate risk of evacuating their villages, according to the UN agency.
In Kunaflusa, a rocky 90-minute drive north of Erbil, the village karez was last year producing only a trickle. Village mukhtar Fadel Abdullah Salah said families were allotted one-hour time slots to fill up enough water jugs to last a week.
"There is not enough water now for farming," said Salah. "If the karez runs dry, we will be forced to leave the village."
Water brought in tanker trucks by the Kurdistan Regional Government has helped the people of Kunaflusa. But experts say quick fixes such as hauling in water or drilling new, gas-fuelled wells are expensive band-aids that will ultimately prove unsustainable.
Salah said the village had some 200 houses in 1984, but today only 13 remain occupied. The UN report found that, on average, 70 per cent of residents moved away from their villages after the local karez went dry.
"There is now not enough water for farming. If the karez runs dry, we will be forced to leave the village. "
- Fadel Salah, Kunaflusa villager
Whether the demise of the karez is due to mismanagement, rapacious drilling, climate change - or a combination of the three - it is certain that the widespread drying up the karez system in Iraq is unprecedented. Experts say that while individual karez have occasionally dried up in the past, they have never experienced such a rate of dehydrated in such a short span of time.
"The karez can be seen as little birds in a mine. It is mind-boggling that thousand-year-old tunnels like the karez have managed to supply water continuously and in the past ten or 20 years they have managed to dry up on a large scale. It's extremely worrying," said Joshka Wessels, a Dutch filmmaker and human geographer who has studied karez systems in the Middle East since 1998.
"This is not limited to karez communities but is [a] region-wide humanitarian disaster if droughts of this scale continue. The most common response is that people will leave and migrate to other locations. The human consequences will be enormous," she added.
How karez changed the world
The karez, also known as a qanat , is recognised as a masterpiece of early engineering. In fact, the dispersal of karez suggest that these millennia-old wonders were once the hottest "new technology" in the ancient world. Although there is some debate, the conventional wisdom is that karez were first built in Iran around 2,500 BC, and by 500 BC the Persians had spread the technology extensively throughout the Middle East and North Africa.
Ingenious in their simplicity, a karez is a series of carefully calibrated tunnels and shafts that harness gravity to draw a continuous flow of underground water to the surface. The Romans are understood to have learned the technology from either the Etruscans or the Egyptians, and went on to further spread the construction of karez - though research shows that Arabs had already built a karez in what would become Madrid by 750 BC.
The water systems eventually made their way to Chile, Peru and Mexico - and even Los Angeles, in present-day California, in 1520AD.
"They're amazing, considering the labour and materials involved and the ingenuity and engineering power it takes to create a tunnel several miles long... These are amazing wonders of the world and nobody knows about them . "
- Dale Lightfoot, Oklahoma State University
Karez also travelled east, across Afghanistan, Pakistan, Central Asia and into north western China where they are prevalent, with a 5,000km network of 1,100 waterways stretching across the Xinjiang Uyghur Autonomous Region.
"They're amazing, considering the labour and materials involved and the ingenuity and engineering power it takes to create a tunnel several miles long," said Dale Lightfoot of Oklahoma State University. "They followed a gradient and made calculations and they couldn't even see what they were doing. These are amazing wonders of the world and nobody knows about them."
From an environmental standpoint, karez have the advantage of never pulling out more water than the aquifer can naturally supply. "Mother Nature manages the withdrawal," said Lightfoot. "It's an inherently sustainable system that could survive for centuries."
In Iraq the United Nations estimates that 50 per cent of all water resources are wasted and six million people have no access to clean water.
In a report released earlier this year, the UN said that, in rural areas, one in four children access their water from rivers and creeks and one in ten rely on water from tanker trucks and open wells. For Iraq, and other water-starved nations in the Middle East and North Africa, the upkeep of karez systems could preserve a vital resource. For hydrologists, saving the karez is a potent mix of cultural value, ancient science and necessity.
"These systems keep on fascinating me because the technology and sheer human effort to bring water to the desert is amazing," said Wessels. "Once you are in a tunnel like that, you can't help imagining that, despite all the current modern technology, these hand-dug hydraulic wonders are still the most sustainable way of using water in the desert."
Save karez, save the future
As karez continue to dry up across Iraqi Kurdistan, due to what Lightfoot calls "the double whammy" of drought and over pumping by mechanical wells, the knowledge of how to build and maintain them is also fading away.
"The process is quite complex, but in general every ten years or so, [karez] have to be cleaned out, relined and air shafts repaired. This entails an intimate knowledge of the hydraulics of the tunnels… The traditional knowledge and oral traditions are vanishing," said Wessels.
Casey Walther, who recently led a European Union funded UNESCO project to rebuild karez in Iraq,admits that saving them is no simple task.
"It's a loss of cultural heritage. This is real Iraqi heritage and it's on the verge of going extinct if measures aren't taken. This knowledge isn't taught in universities . "
- Casey Walther, UNESCO researcher
"The karez in Iraq are on the verge of dying out," he said. "The Anfal campaign [Saddam Hussein’s war against the Kurds] was devastating on the systems in the 1980s and 1990s. This has been combined with the rise of modernity and urban migration; young people are drawn to exciting opportunities in cities, not sitting in a village learning an old trade.
"It's a loss of cultural heritage. This is real Iraqi heritage and it's on the verge of going extinct if measures aren't taken. This knowledge isn't taught in universities."
The demise of the karez wells couldn't come at a worse time for Iraq. The Tigris and Euphrates rivers are losing an estimated 50-70 per cent of their flow in Iraq due to increased withdrawals and damming in Turkey and Syria, while at least 250,000 tons of raw sewage is pumped into the Tigris river every day, "threatening unprotected water sources and the entire water distribution system".
Officials estimate that two million people have severe shortages of drinking water. Already a drought-stricken nation downstream from thirsty neighbours, the advent of climate change stands to only make matters worse.
The positive role that a revived karez system could play in mitigating this deepening water crisis is undeniable, according to experts.
"The karez are certainly part of a solution to many problems, including how to keep folks in the village and stem depopulation in the countryside; how to sustainably utilise groundwater resources instead of over-pumping the aquifers," said Lightfoot. "They could also play a role in reversing desertification, but only if the karez are still flowing."
Investment for well-being
UNESCO's Walther points out that the "easy fix" for an area without water is to keep drilling more and deeper wells. But the karez trump the modern well in terms of sustainability and resilience to variations in climate, he noted.
"The message today is that karez, though an ancient technology, is a better solution to water scarcity in many situations today, and should be used more widely as a tool for supplementing water supplies in arid regions," he said.
"It is a simple technology that requires very little start-up investment, and if used correctly can provide enough water for small communities without exhausting the aquifer."
"The message today is that karez, though an ancient technology, is a better solution to water scarcity in many situations today, and should be used more widely as a tool for supplementing water supplies in arid regions . "
- Casey Walther, UNESCO researcher
It seems others are listening. The government of Iran, for example, funded the development of the International Centre on Qanats and historic Hydraulic Structures - a research and training facility aimed at karez conservation.
Success stories have even emerged from Iraqi Kurdistan. In Shekh Mamudian, the village water supply has been revived and improved.
In a pioneering intervention led by Walther's UNESCO team, two experts were brought in from Iran - one a young engineer and the other an elderly karez maker. The Iranian masters worked with six local men to clean out and refurbish the karez, and, after more than a month's labour, the village karez was gurgling nicely into the pool at the foot of the mosque once more.
The UNESCO team concluded that the improved flow of water was enough for the Shekh Mamudian villagers to resume old farming practices, and more karez repairs were planned in other areas.
"We thought water would never run through the karez again," said Ali, the village mukhtar. "But when the Iranians, who have a lot of experience, came, they told us we could fix it. They said there was a river under the ground and told us they would be able to bring the water up through the karez.
"We believed them and now we are very satisfied."
Despite what could be the beginnings of a karez revival in Kurdistan, the future is still bleak for the water systems amid Iraq's vast environmental problems, not to mention its endemic instability, corruption and poverty.
Kunaflusa is still struggling to get by on tanker water and a trickle from the karez. Experts worry it might be too late to rehabilitate the ancient system there.
"If you consider the functionality and ingenuity behind the karez, these are marvels of ancient scientific technology," said Walther.
"But without human intervention, these systems will stop flowing and be lost forever."
Follow Charles McDermid on Twitter: @CharlesMcDermid