The karez system, designed in ancient Persia to cope with an arid climate, is a man-made underground system that for centuries has provided Iraqis with drinking water and irrigation needs. A single karez is able to provide water for nearly 9,000 individuals and 200 hectares (500 acres) of farm land, the UN agency said in a press release.

Paris (AFP) Oct 13, 2009 – More than 100,000 people in northern Iraq have abandoned their homes since 2005 because of water stress, after drought and over-extraction of groundwater caused the collapse of an ancient water system, UNESCO said on Tuesday. “Drought and excessive well pumping have drawn down aquifer levels in the region, causing a dramatic decline of water flow in ancient underground aqueducts” known as karez, the UN’s Educational, Scientific and Cultural Organisation (UNESCO) said. The karez system, designed in ancient Persia to cope with an arid climate, is a man-made underground system that for centuries has provided Iraqis with drinking water and irrigation needs. … The system, already badly affected by political turmoil and neglect, has been dealt a devastating blow by over-pumping of aquifers by modern wells at a time of drought, UNESCO said. Since the onset of the drought four years ago, 70 percent of the functioning karez in northern Iraq have dried up, specialists found. By August this year, only 116 of 683 karez systems in northern Iraq were still functioning. “The rapid decline of karez is forcing entire communities to abandon their homes in the pursuit of new sources of water,” it said. “Population declines have averaged almost 70 percent among the communities adversely affected since 2005.” It added: “An additional 36,000 people are on the brink of abandoning their homes if conditions do not rapidly improve. …

Water shortages causes 100,000 to flee homes in Iraq: UN