A qanats is a system of water supply consisting of a ground tunnel connected to the surface by a series of shafts, which uses gravity to bring water table to the surface. Qanats are usually dug where there is no surface water and were originally invented by Iranians. It is believed that around 800 BC, coal miners in northeastern Iran improvised some canals in order to extract the water from the coal mines. The technology was gradually applied by farmers and spread all over the plateau of Iran. About 525 BC it reached Oman and Saudi Arabia by Iranians and Persian campaigns.
Muslims introduced Qanat to Africa and Yafuga (a qanat) was created by Muslims in Madrid about 750 BC. The Spanish initiated qanats in Mexico in 1520 AD. From there, it was taken to Los Angeles in 1520 AD. This Hydraulic system was spotted in Chile, too. Creation of qanats in Asia enjoys great antiquity as well. Qanats are also known as ‘karez’ (Afghanistan), ‘galeria’ (Spain), ‘khotara’ (morocco), ‘aflaj’ (Arabian peninsula), ‘forggara’ (north Africa), ‘kanerjing’ (china), ‘auon’ (Saudi Arabia/Egypt), reflecting the widespread dissemination of the technology across ancient trading routes and political maps.
The immediate outlet, mazhar, is the point is very important: it is well maintained and cemented.
The use of water use is monitored on regular basis. A tunnel, or payab, channels water under the residential area to the cultivated land. A sloping corridor with steps leads from the surface to the payab. The first payab is located in the main square and is used for taking drinking water. A network of smaller payabs runs from the main payab.
The three work zones
Mazhar: The mouth of the qanat (Source: www.unfccc.int)
Source: International symposium on groundwater sustainability (ISGWAS)
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