The Koohrang (also known as Kouhrang and Kurang) is a river originating in the

Zagros The Zagros Mountains are a mountain range in Iran, northern Iraq, and southeastern Turkey. The mountain range has a total length of . The Zagros range begins in northwestern Iran and roughly follows Iran's western border while covering much of s ...

mountains of western

Iran Iran, officially the Islamic Republic of Iran (IRI) and also known as Persia, is a country in West Asia. It borders Iraq to the west, Turkey, Azerbaijan, and Armenia to the northwest, the Caspian Sea to the north, Turkmenistan to the nort ...

, which joins the Beheštābād river () to form the

Karun The Karun (, ) is the Iranian river with the highest water flow, and the country's only navigable river. It is long. The Karun rises in the Zard Kuh mountains of the Bakhtiari district in the Zagros Range, receiving many tributaries, such as ...

, Iran's largest (by volume) river. A series of tunnels (Kuhrang Tunnels) have been built since the 1950s to redirect some of the Kuhrang's water toward the

Zayandeh River The Zayanderud or Zayandehrud (; from "fertile" or "life-giver", and "river"), also spelled as ''Zayanderud'' or ''Zayanderood, ...'', is the largest river of the Iranian Plateau in central Iran. Geography The Zayandeh starts in the Zard- ...

to meet the demands of increased population in

Esfahan Isfahan or Esfahan ( ) is a city in the Central District of Isfahan County, Isfahan province, Iran. It is the capital of the province, the county, and the district. It is located south of Tehran. The city has a population of approximately ...

and

Yazd Yazd (; ) is a city in the Central District of Yazd County, Yazd province, Iran, serving as capital of the province, the county, and the district. At the 2016 census, its population was 529,673. Since 2017, the historical city of Yazd is rec ...

provinces. The

basin encompasses about and is connected to the upper

River basin (which drains to the Persian Gulf) by the

Kuhrang Dam and Tunnel 1 The Kouhrang 1 Dam is a masonry gravity dam on the Kouhrang River about southwest of Chelgard in Chaharmahal and Bakhtiari Province, Iran. The primary purpose of the dam is to divert up to of water annually via the long Kouhrang 1 Tunnel to t ...

() constructed in 1953 although first proposed in the early sixteenth century. Two additional tunnels ( Kurang 2 and Kurang 3) were constructed in late 1990s and early 2000s. A hydroelectric dam at Godar-e Langar (also known as Karun-4) would also supply piped water to Esfahan away if it is completed (Whitley and Gallagher, 1995). Dams have deleterious effects on a riverine fish and other fauna and are often stocked with exotic species. The upper Karun has not been well explored for endemic taxa. Mean annual flow of the Zayandeh River is estimated at and is used mostly for agriculture, but an increase in population and industry has necessitated dam construction ( Chadegan Reservoir, capacity ) and diversion schemes. There is also the Hana Dam on the Hana River at

Semirom Semirom () is a city in the Central District of Semirom County, Isfahan province, Iran Iran, officially the Islamic Republic of Iran (IRI) and also known as Persia, is a country in West Asia. It borders Iraq to the west, Turkey, ...

with a height of and a capacity of .

References

Rivers of Chaharmahal and Bakhtiari province Chaharmahal and Bakhtiari province Khuzestan province {{Iran-river-stub