Kara Darya
The Kara Darya is a major river in southern Kyrgyzstan and eastern Uzbekistan located in the eastern part of Fergana Valley. It is one of the two source rivers of the Syr Darya, the other source being the Naryn. Its length is, and watershed area. The Kara Darya is formed by the confluence of the rivers Kara-Kulja, which rises on the southwestern slopes of the Fergana Range, and Tar.
Course
The river’s upper course flows through narrow valleys, while the middle and lower courses pass through broad valleys. The upper Kara Darya flows northwest across eastern Osh Region southwest of and parallel to the Fergana Range. It enters the Fergana Valley and Uzbek territory a few kilometres west of Özgön.Hydrology
The basin contains about 40 lakes, including Chong Kulun, Kichi Kulun, Chong Köl, Kichi Köl, Kabylandköl, Karaköl, and Kutmanköl.Average annual discharge near Kempirabad is, with seasonal maxima of 676 m³/s and minima of 28.9 m³/s.
The flow regime is sustained by approximately 32% snowmelt, 16% glacier meltwater, and 52% groundwater.
Irrigation and infrastructure
In its lower course through the Fergana Valley the Kara Darya is extensively harnessed for irrigation. Major hydraulic works include a dam at Kuyganyor where part of its water is diverted into the Great Fergana Canal. The Andijan Dam, built in 1973, created the Andijan Reservoir. Numerous irrigation canals branch from the river and its tributaries, such as the Kochkorata, Otuzadyr, Uval, Altybay, and Naiman.Tributaries
; Right-bankJazy, Kögart, Kara-Üngkür, Mailuu-Suu
; Left-bank
Kurshab, Aravansay
In total, the Kara Darya has more than 200 tributaries.