Mongolia in Perspective

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Rivers and Lakes

Rivers

Broadly, Mongolia’s rivers flow in three different
directions: northward to rivers draining into the
Arctic Ocean, eastward to rivers that flow into the
Pacific Ocean, and southward into desert basins
with no outlets to the sea.^36 The largest
Mongolian river is the Selenge, which originates
in the north-central part of the country. The
Selenge’s main tributary, the Orhon River, joins it
near the Russian border, from which the Selenge
then flows northward into Lake Baikal (the
world’s deepest and oldest lake).^37 The Selenge is only navigable from the late spring to
early fall, with ice blocking the river the rest of the year.^38

In eastern Mongolia, the two main rivers are the Herlen and the Onon, both of which
originate on the eastern flanks of the Hentiyn Mountains. The Herlen eventually flows
into Hulun (Dalai) Lake in northeastern China. In rainy years, Hulun Lake overflows its
banks and connects to the Argun-Amur River, a long river system that forms the
boundary between Russia and China for much of its distance. The Onon also connects to
the Amur River via a route that swings north through Russia.
39

Most of the Mongolian rivers that end in desert basins are relatively short. Two
exceptions are the glacier-fed Hovd River and the Dzavhan River. Both of these rivers
eventually drain into the Great Lakes Depression of western Mongolia.
40

(^36) Donald R. DeGlopper, “Chapter 2: The Society and Its Environment: Geography: Landforms,” in
Mongolia: A Country Study, 2nd ed. (Washington, DC: U.S. Government Printing Office, 1991), 63.
(^37) EarthRacts.net, “Lake Baikal,” 2011, http://www.earthfacts.net/places/lake-baikal/
(^38) Encyclopædia Britannica Online, “Selenga River,” 2011, http://www.britannica.com/EBchecked/topic/
533218/Selenga-River
(^39) Amur-Heilong.net, “Amur-Heilong River Basin: Where is the Tail of the Black Dragon?,” n.d.,
http://amur-heilong.net/http/01_climate_waters/0124watermongolia.html
(^40) Encyclopædia Britannica Online, “Mongolia: The Land: Drainage,” 2011,
http://www.britannica.com/EBchecked/topic/389335/Mongolia