Isfana River


The Isfana River, also called Isfanasoy and Andarsoy in its lower course, is a north-flowing transboundary river in Central Asia. It is approximately long and flows through Razzakov, which was also called Isfana until 2022. The river's course runs through Kyrgyzstan and Tajikistan, from the Turkestan Range into the Syr Darya. Most of the river's water is diverted for irrigation or seeps into the ground, and as such it rarely reaches the Syr-Darya.
The Isfana is fed by unnamed glaciers on the northern flank of the Turkestan Range as well as groundwater. It has 31 tributaries, most of which meet in and around Razzakov. One of the several transboundary rivers in the Syr-Darya basin, the Isfana River flows parallel to the Khojabakirgan River. International donor organizations have supported the establishment of small basin councils in the Isfana River basin, particularly in Tajikistan.

Name

The word "isfana" is believed to have come from the Sogdian word asbanikat, asbanikent or aspanakent which means "the land of horses". In Kyrgyz, the river is called Isfana suusu, and in Uzbek it is called Isfana soyi or Isfanasoy, which means the "Isfana Creek". In its lower course, the River is also called Andarsoy, since it passes through the village of Andarsoy in Tajikistan.

Course

The headwaters of the Isfana are several unnamed glaciers at roughly elevation in the northern region of the Turkestan Range called Altynbeshik. The upper portion of the river flows roughly north and northwest. As it passes through the Dagana Gorge into the Toojayloo basin, the river disappears underground. The dry riverbed runs through the Isfana-Kara-Bulak basin and reaches eastern Razzakov, where it reemerges and is fed by several artesian wells.
The Isfana River has 31 tributaries. The portion of the river that runs west from the Dagana Gorge to eastern Razzakov is called Tegirmenlik, and the portion that flows through Razzakov is called the Say, which literally means a "creek". In central Razzakov, the Say receives the Cholgan Creek, also fed by an artesian well, from the right.
In the north-west of Razzakov, the Say joins the Taylan Creek, forming the Isfana River proper. The Taylan Creek is also fed by several unnamed glaciers at roughly elevation in Kekche-Tau Mountain in the Turkestan Range. The portion of the Taylan Creek that runs from the eponymous village through Razzakov until it merges with the Say is called the Uzunsay.
After travelling north from Razzakov for roughly, the Isfana River enters Jabbor Rasulov District of Tajikistan.

Tributaries

Tributaries of the Upper Isfana include:
  • Tegirmenlik / Say
  • Taylan / Uzunsay

Hydrology

Sources differ on the length of the Isfana River, putting it from to long. Most of the annual runoff of the river occurs from May to June, with lowest water levels from February to March.
The Isfana River has an average discharge of anywhere between - to. Along with the Ak-Suu and Khojabakirgan river basins, the Isfana river basin sits above the Suluytka–Batken–Nau–Isfara transboundary aquifer in the Syr Darya Basin.
In the spring, the Isfana River often overflows, causing flash floods. Flash floods in the river's basin have become more common since the late 1980s.