Qanats: The OG Water Delivery System Since 1000 BCE
The Persian Qanat: Qanats of Bam
Date: 11/12/2014
Copyright: © S.H. Rashedi
The Persian Qanat: Aerial View, Jupar, Bagh-e Shahzadeh (Mahan)
Date: 10/12/2014
Copyright: © S.H. Rashedi
Picture this: some 3,000 years ago, ancient engineers figured out how to deliver water across miles of bone-dry land—no pumps, no electricity, just pure underground brilliance. These were the qanats: a water system so ingenious that modern engineers might just shed a tear. Developed in the dry lands of Persia, qanats were the original answer to water scarcity, quietly and efficiently flowing beneath the surface.
A qanat is a remarkable water supply system designed to transport water across long distances. It consists of an underground tunnel connected to vertical shafts that start at a well, tapping into deep water sources and channeling them to the surface. As the water travels, it’s naturally filtered through layers of earth, emerging cool, fresh, and low in pollutants, even in hot, dry climate. This water is often slightly sweet, helping to wash away salty soils downstream. Ingeniously, qanats prevent evaporation and operate entirely through gravity, eliminating the need for pumps. They are also highly resilient, remaining largely unaffected by climate extremes and resistant to human interference.
Qanat in Kashan surfacing within the Fin Garden; it is thought to have served Iran's Sialk area for thousands of years.
By Zereshk at the English-language Wikipedia, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=16377584
Water channel of Qanats of Ghasabeh, Iran
By Tavasoli mohsen - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=94710435
The qanat systems were developed by Persians in ancient Iran and the fact, that their use spread gradually throughout the whole region of the Middle East, Africa and Europe, is a testament to it’s important use and efficiency. Historical records indicate that similar systems were developed independently around the same time in China and South America. However, whether the Chinese qanats were influenced by Persian designs remains a topic of scholarly debate.
Qanats typically originate at the base of mountains, where the water table is closest to the surface. From this point, the qanat tunnel gradually descends, aligning with the steeper slope of the land above, allowing water to flow to the surface where the two levels meet. To transport water from an aquifer to populated or agricultural areas, qanats often need to stretch over considerable distances.
Additionally, qanats may branch into an underground network of smaller channels known as kariz. Similar to qanats, these smaller canals remain buried to protect the water from contamination and evaporation. In some instances, water from a qanat is stored in a reservoir, with nighttime flow collected for use during the day. An example of this is an ab anbar, a traditional Persian reservoir fed by qanat water, designed specifically for drinking purposes.
An Ab Anbar cistern in a qanat water system, located in the Iranian desert city of Naeen.
CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=1295580
Qanats were so essential in Persia that their locations often determined where towns were established and significantly influenced their growth. As the backbone of agricultural development, qanats enabled the expansion of farmland, and in some cases, farmland grew around them. Beyond supporting settlements and agriculture, the qanat system also inspired a unique style of desert architecture and landscape design, incorporating reservoirs, mills, irrigation channels, and gardens. This remarkable engineering feat played a crucial role in shaping Persian civilization and its development.
Exploring the history of qanats is fascinating, as there is substantial documentation regarding their evolution. Notably, inscriptions from Sargon II, the Assyrian king, reveal that during a campaign in Persia around 714 BC, he discovered an underground system for accessing water. His son, King Sennacherib, later utilized this "secret" of subterranean conduits to construct an irrigation system in Nineveh. Between 331 and 550 BC, during the Persian Empire’s expansion from the Indus River to the Nile, qanat technology proliferated throughout the region. The Achaemenid rulers incentivized qanat builders and their descendants by permitting them to keep the profits from newly constructed qanats for five generations.
Qanats spread widely from their origins, extending westward from Mesopotamia to the Mediterranean coast and southward into Egypt and North Africa. To the east, they appeared in Afghanistan and the Silk Route oasis settlements of Central Asia, reaching as far as Chinese Turkistan. During the Roman-Byzantine period (64 BC to 660 AD), numerous qanats were constructed in Syria and Jordan. Later, Berbers fleeing Cyrenaica brought qanat technology to the Central and Western Sahara around 118 AD, while the spread of Islamic culture introduced qanats to additional areas of North Africa and parts of Europe, including present-day Italy, Cyprus, and Spain.
Qanats are found in approximately 35 countries worldwide, with the majority concentrated in Iran, and they remain in use across many regions today. In Iran, Persian qanats are listed on the national register of monuments, and their catchment and irrigation areas are safeguarded within designated buffer zones. Additionally, they hold UNESCO World Heritage status, highlighting their cultural and historical significance.
Used sources for this article: WaterHistory.org ; Review of Ancient Wisdom of Qanat, and Suggestions for Future Water Management