The Ancient Qanat: Sustainable Water Management Systems in Iran and the Middle East

On December 26, 2003, a devastating earthquake measuring 6.6 magnitude struck Bam, Iran, claiming the lives of approximately 26,000 people and injuring another 30,000. The earthquake also caused extensive destruction, including the collapse of the renowned Bam Citadel, known as Arg-e-Bam. This tragic event unveiled an ancient water management system known as the qanat, believed to have been built during the Achaemenid Empire in ancient Persia (550–336 BC). The city of Bam, located in southern Iran, has long been recognized for its historical significance and well-preserved ancient mud-brick structures. Unfortunately, the earthquake caused widespread damage, reducing the once-famous citadel to ruins.

Regions such as Iran and the broader Middle East are characterized by arid and barren climates. The long dry seasons and limited rainfall lead to chronic droughts. In Iran, the average annual rainfall ranges around 273 millimeters. The southwestern region of Iran, like Khuzestan Province, experiences higher rainfall, averaging around 300 to 500 millimeters per year. Water was considered sacred, alongside fire and earth, in ancient Persian mythology, known as Zoroastrianism. These three elements were to be protected and preserved. However, in arid lands like Persia, water was not easily accessible. To meet their water needs, the ancient Persian communities developed an ingenious method. They exploited, preserved, and stored water through a system called the qanat.

The term “qanat” originates from Arabic, meaning “channel,” and often serves as a general reference to ancient irrigation systems. In the Persian language, this system is known as “kariz,” while it is called “foggara” in Algeria, “khettara” in Morocco, “aflaj” in Oman, “galeria” in Spain, and “kanerjing” in China. Physically, a qanat is an irrigation system designed to transport water from an aquifer or water well to the surface through underground channels. By utilizing the natural slope of the underground terrain, water from the highest well flows by gravity to the lowest well, making it easily accessible.

The roots of qanat can be traced back to the 1st to 7th centuries BC, during the ancient Persian civilization. Inhabiting arid regions, the Persians faced challenges accessing the hidden groundwater beneath the surface. Since the 6th century BC, the Eastern Zagros Mountains region has been excavating qanats to overcome the arid climate. In the early 7th century BC, the Assyrian King of Mesopotamia, Sargon II, reported discovering the underground water extraction system during his expansion into Persia. His son, King Sennacherib, implemented a similar approach and secretly constructed irrigation projects in his territories near Nineveh, an ancient city on the banks of the Tigris River. The qanat technology then spread throughout the Persian Empire, with thousands of new settlements established in various regions.

The Roman-Byzantine era (64 BC–660 AD) also witnessed the construction of numerous qanats in Syria and Jordan, where the technology spread northward and westward. During the spread of Islam, policies were introduced to encourage the diffusion of qanat technology, leading to its dissemination across North Africa, Cyprus, Sicily, Spain, and the Canary Islands. In Spain, qanats began to be utilized for agricultural purposes and urban development. Qanats also played a significant role along the Silk Road, stretching from Persia to Central Asia and China.