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Aflaj


A Qanāt or karez/kariz (Persian: قنات‎‎/کاریز) is a gently sloping underground channel to transport water from an aquifer or water well to surface for irrigation and drinking. Qanat is an old system of water supply from a deep well with a series of vertical access shafts, Qanāts still create a reliable supply of water for human settlements and irrigation in hot, arid, and semi-arid climates. The qanat technology is known to have been developed in Iran by the Persian people sometime in the early 1st millennium BC, and spread from there slowly westward and eastward.

Qanat is the Arabic word for "channel" (قناة). Qanats in Persian called kārīz (or kārēz from Persian: كاريز‎‎) (Iran, Afghanistan, Pakistan and Central Asia, derived from Persian: كاهریز‎‎), kahan (from Persian: کهن‎‎), Kahn (Baloch), kahriz/kəhriz (Azerbaijan); khettara (Morocco); Canal (Spain); falaj (from Arabic: فلج‎‎) (Emirates and Oman) or foggara/fughara (North Africa). Alternative terms for qanats in Asia and North Africa are kakuriz, chin-avulz, and mayun. Common variants of qanat in English include kanat, khanat, kunut, kona, konait, ghanat, ghundat.

Qanats are constructed as a series of well-like vertical shafts, connected by gently tunnels. Qanats efficiently deliver large amounts of subterranean water to the surface without need for pumping. The water drains by gravity, typically from an upland aquifer, with the destination lower than the source. Qanats allow water to be transported over long distances in hot dry climates without much water loss to evaporation.


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