Irtysh River

Irtysh is a river that flows through Russia, China, and Kazakhstan. It is the Ob's main tributary, as well as the world's longest tributary river. The river's source is in the Mongolian Altai, near the Mongolian border in Dzungaria (the northern portion of Xinjiang, China). The Tobol, Demyanka, and Ishim are three of the Irtysh's primary tributaries. Most of Western Siberia and the Altai Mountains are covered by the Ob-Irtysh system, which is Asia's largest drainage basin.

The Irtysh begins as the Kara-Irtysh in the Mongolian Altay highlands of Xinjiang, China, and runs northwest through Kazakhstan's Lake Zaysan, where it meets the Ishim and Tobol rivers before joining with the Ob near Khanty-Mansiysk in western Siberia, Russia (2,640 mi). Some authors, particularly in Russia and Kazakhstan, refer to the upper course of the river, from its source to Lake Zaysan, as the Black Irtysh. The phrase White Irtysh was once used to refer to the Irtysh below Lake Zaysan, in contrast to the Black Irtysh; however, this usage is now completely extinct.

During the ice-free season, which runs from April to October in Kazakhstan and Russia, tankers, passenger ships, and cargo ships navigate the river. Omsk is the largest river port in Western Siberia and is home to the state-owned Irtysh River Shipping Company's headquarters. There are three main hydroelectric plants on the Kazakhstan section of the river: Bukhtarma, Ust-Kamenogorsk, and Shulbinsk. With a drop of 42 meters (138 feet), the world's deepest lock allows river flow to bypass the dam at Ust-Kamenogorsk. There are plans in place to build several more dams.

Length: 4248 km