Manych

Formerly, at least in periods of high water, the Manych River would flow in two directions. The river Kalaus, when reaching the Kuma–Manych Depression at 45°43′N 44°06′E, would split. About 30% of the water would become the West Manych and flow northwest to, or toward, the Don River. The remaining water became the East Manych and flowed roughly southeast and dried up on the steppe before reaching the Caspian Sea. Sometime around 1970 a low dam was built which prevented any water from flowing into the East Manych. The East Manych is now fed by irrigation canals coming from the Kuma and Terek Rivers.[3]

Historically (prior to the construction of the dams and irrigation channels, i.e. until 1932–1940 for the West Manych, and until 1969 for the East Manych), both rivers were intermittent. During dry years, and even during the drier parts of normal years, both Manych Rivers would consist merely of a chain of small lakes or ponds with brackish or salty water. The system usually would be fully filled with fresh water only during the spring freshet.[3]

Since the mid-20th century both Manych Rivers receive significant amounts of fresh water via a network of irrigation canals. Since 1948–1953, the West Manych has been receiving water from the Kuban River (via the Nevinnomyssk Canal and the Yegorlyk, a left tributary of the West Manych) and from the Tsimlyansk Reservoir on the Don (via the Don Canal). Since the late 1960s, the East Manych has been receiving water from the Terek River and the Kuma River via the Kuma–Manych Canal. According to A. Bazelyuk's calculations, the annual water flow in the West Manych (measured at the Vesyoly township) is 8.3 times as high as it was previous to the canal and dam constructions, while that in the East Manych (measured at the Chogray Dam) is 4.3 times as high as before.[3]

If the plans for the proposed Eurasia Canal, linking the Caspian Sea with the Black Sea, are ever implemented, it will likely follow the Manych valley in its central and western section.