Bolshoi Fergana Canal

(full name, U. Iusupov Bol’shoi Fergana Canal), a canal in the Fergana Valley in the Uzbek SSR (283 km) and the Tadzhik SSR (62 km); one of the largest irrigation systems of the USSR. Built in 1939–40 by a citizen volunteer force of 160,000 collective farm workers.

The Bol’shoi Fergana Canal originates in the Naryna River, the basic source of the Syr Darya River, near Uch-kurgan, and, crossing the Karadar’ia and several left tributaries of the Syr Darya, it follows the southern side of the valley and ends at the Syr Darya near Leninabad.

There are more than 1,000 hydrotechnical plants located on the canal, more than 50 of which are substantial. The canal supplies water to the Naryna and Karadar’ia rivers and is used for the water control of the rivers of the southern boundary of the Fergana Valley and for direct irrigation of adjacent lands. Approximately 257,000 hectares of land are irrigated, 100,000 ha by the canal alone; the remainder receives its water from both the canal and the river system connected to it.

In 1940–41, the Iuzhnyi Fergana and Severnyi Fergana canals were also constructed. As a result, the water supply to the irrigation systems of the valley increased considerably, as did the area irrigated, and the cotton harvest doubled.