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WonderEngineering history fact

A qanat is an underground channel, developed in ancient Persia, that brings groundwater from the foot of hills to fields and towns using gravity alone. From above, a qanat shows as a line of shaft openings across dry land.

UNESCO, The Persian Qanat, 2016

EngineeringHistoryClimateTechnology

The story behind the card

Builders start with a 'mother well' dug down to the water table, then cut a tunnel back towards the surface on a very gentle slope, so the water flows without wearing away the channel. Vertical shafts along the route let workers lift out soil, bring in air and later clean the tunnel. The Qasabeh qanat at Gonabad in eastern Iran, dated to between 700 and 500 BCE, has a mother well more than 360 metres deep and about 33 kilometres of channels, and still carries water. In 2016 UNESCO listed eleven Iranian qanats together as a World Heritage site, recognising both the engineering and the old customs for sharing the water fairly.

Türkçe oku
Kehriz (Farsça kanat), eski İran'da geliştirilmiş bir yeraltı kanalıdır: Tepelerin eteğindeki yeraltı suyunu yalnızca yerçekimiyle tarlalara ve kasabalara ulaştırır. Yukarıdan bakınca kurak toprak boyunca sıralanmış kuyu ağızları gibi görünür.
UNESCO, Pers Kehrizi, 2016

Yapımı bir “ana kuyu” ile başlar: Bu kuyu yeraltı suyunun bulunduğu derinliğe kadar kazılır. Ardından yüzeye doğru çok hafif eğimli bir tünel açılır; böylece su kanalı aşındırmadan akar. Güzergâh boyunca açılan dikey kuyular, işçilerin toprağı dışarı çıkarmasını, tünele hava girmesini ve sonradan temizlik yapılmasını sağlar. İran'ın doğusundaki Gonabad'da bulunan ve MÖ 700-500 yılları arasına tarihlenen Kasabe kehrizinin ana kuyusu 360 metreden derindir, kanallarının toplam uzunluğu 33 kilometreyi bulur ve hâlâ su taşır. UNESCO 2016'da İran'daki on bir kehrizi birlikte Dünya Mirası Listesi'ne aldı; hem mühendisliği hem de suyun hakça paylaşılmasına dair eski gelenekleri tanıdı.

Sources and further reading

Background reading: Qanat
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