Turpan’s old water system is parched
2,000-YEAR-OLD HAND-DUG TUNNELS FOR IRRIGATION IN CHINA ARE DRYING UP
t is an improbable journey that begins on the highest peaks of the Tianshan Mountains, where glacial snowmelt descends across one of the world’s most arid landscapes to reach the lush oasis communities of this ancient Silk Road outpost.
Powered by gravity, the water — pure and cold — makes the entire voyage underground, travelling through scores of subterranean channels, some of them 24km long and 30-metres deep, that were built 2,000 years ago by the pastoralists who settled in this inhospitable corner of China’s farwestern Xinjiang region.
Known as karez, the system of channels is an engineering marvel that has long fascinated scientists and filled this city’s ethnic Uighurs with pride.
“Our ancestors were amazing because they built these without machines,” said Salayidin Nejemdin, 29, whose family has been growing grapes in Turpan for generations. “Without them, we would not be able to live in such a harsh place.”
But after millenniums of nourishing the region’s farmers, goat herders and cross-continental traders, the karez channels of Turpan are drying up. Although scientists say global warming has shrunk the glaciers that feed the elaborate irrigation system, the more immediate threat is the soaring demand for water from the petroleum drillers and industrial-scale farmers, who are sucking the Turpan Basin dry.
There are just over 200 working karez in the region, down from nearly 1,800 in the 1950s, according to government figures. Every year, as many as a dozen of the underground tunnels run dry. Others, contaminated by oil, are abandoned.
Threat to way of life
Shalamu Abudu, a hydrology expert at Texas A & M AgriLife Research Centre at El Paso, who has written extensively about Turpan’s hand-dug tunnels, said their disappearance threatens a way of life that has persevered against all odds.
Turpan, he noted, occupies one of the world’s hottest locales: a parched depression, devoid of rivers, that receives an average of just over a halfinch of rainfall a year.
“The karez is a symbol of our civilisation,” said Abudu, a Uighur, who until recently worked for the state-run Xinjiang Water Resources Research Institute.
The water helps sustain the region’s half a million residents and ensures that Turpan’s family farms can grow the grapes that have shaped the city’s identity for centuries. Grape arbours grace nearly every home here, and the rural landscape is dotted with imposing brick-and-mud drying towers, where the grapes are turned into raisins.
Standing beneath a tangle of grape vines, Mijiti Saludin, 32, said he and his wife were forced to buy water from the municipal government after the karez across from their home ran dry several years ago. “We used to get it for free, but now we have to pay for our water and it isn’t very clean,” he said.
The Chinese government recognises the threat to the
Resident
region’s karez, and in recent years it has sought to ban the drilling of new wells that have contributed to a steady drop of the water table. In 2008, the regional government announced a $182-million project, funded in part by a loan from the World Bank, to protect and rehabilitate the system.
According to government estimates, the aquifer beneath the Turpan Basin shrinks by about 3 million cubic metres a year, much of it because of oil drilling and agriculture.
Despite efforts to keep the karez system alive, some officials appear resigned to its demise. “There is no need to make a fuss about the drying of the karez,” Lu Zhen, the former head of the water resources research institute in Turpan, told the state-run People’s Daily newspaper. “It is a historical certainty that the karez be replaced.”
“Our ancestors were so smart, banding together to solve the water problem,” Nejemdin said, “but these days, being smart is not enough to keep our traditions alive.”