Top 10 Longest Rivers In The World

Last updated on April 12th, 2022

7. The Ob-Irtysh: the world’s seventh longest river system

The Ob-Irtysh rivers combine to create one of the largest river basins in the world. Despite the enormous size, the Ob-Irtysh River drain a region that is extremely sparsely populated and which is yet undiscovered by outsiders. The Ob-Irtysh rivers flow from the mountain ranges of Central Asia through the sparsely occupied Western Siberia to the Kara Sea, which is a subsidiary of the Arctic Ocean.

1. The Ob-lrtysh River is the largest river in Russia and the seventh longest in the globe. The origin of the river is the Asia Altai Mountains and it flows for 3,362 miles into the Arctic Ocean.

2. The Ob-lrtysh River is mostly covered by the West Siberian Plain and the remaining part is covered by rolling hills and plains of Kazakhstan. The river also stretches across semi-desert areas, plains, and grasslands.

3. The Ob-Irtysh River is frozen half of the year and the remaining time is heavily used for transportation. The river is known as the Ob-Irtysh River as its main tributary is the lrtysh river.

4. From April to October, the river is used for transportation in and out of the world. It is also used for irrigation of crops, supplying water to homes, and a big source of hydroelectric power.

The Ob-Irtysh on map

5. Three hydroelectric projects are already established along the Ob-lrytsh; one on the Ob near Novosibirsk and the other two on the lrtysh at Oskemen and Bukhtarma. The river’s potential for hydropower is huge, estimated at 250 billion Kilowatts.

6. Ob-Irtysh River supports fishing activities for commercial use, and the Ob estuary forms one of the biggest fishing industries in the Russian Arctic. Fish species found here include the roach, carps, perches, sturgeon and burbot.

7. Avian and mammalian species are also in plenty along the river basin. For instance, over 150 bird species can be traced in the river basin. Mammals you are likely to find here include wolves, minks, otters, Siberian moles and ermines.

8. The lrtysh is not the only tributary to this gigantic river. Other tributaries include the Tom, the Chulym, the Vakh, the Ket, the Tym, the Vasyugan and the Sosva.

A road bridge across the Ob river. the world's seventh longest river
A road bridge across the Ob river. Image credit – Dmitry Karyshev

9. The Turkic and Mongol people recognize the Ob-lrtysh River as their main site of ancient civilization. Famous battles fought along the Ob is the Battle of lrtysh River fought between the Western Turkic Khaganate and the Tang dynasty.

10. The Tang dynasty may have triumphed over the Turks, but it was not the last battle. For many years, many dynasties have gone to battle on Ob-Irtysh basin, which is today controlled by three countries: China, Russia and Kazakhstan.

11. The Ob-Irtysh River is an integral part of the freshwater habitat in the polar regions of Russia and Kazakhstan. The region drained by the Irtysh prevails a predominantly continental climate.

12. The enormous potential of the Ob-lrtysh River was discovered by explorers in the 17th and 18th Centuries. Buoyed by the massive economic potential, the upper, and middle river courses were first mapped, followed by the lower courses.

On the way to Siberia; Omsk city, Irtysh River
On the way to Siberia; Omsk city, Irtysh River. World’s top ten rivers. Image credit – Ninara

13. Vegetation along the Ob – Irtysh River vary greatly, and this diversity makes the River basin a sight to behold. Along its course, you are likely to find steppes, marsh wetlands and coniferous forests.

14. The Ob-Irtysh River has not been spared the effects of industrial development. For instance, the proliferation of industries in the Altai Mountains in Xinjiang province of China has affected water quality in this river.

15. The ever-growing population of China coupled with China’s heavy industrial water use has continually reduced the Ob-Irtysh River water stock. The over extraction of water has seen water shortages downstream in Russia and Kazakhstan.

16. The disagreements regarding how to exploit the potential of the Ob-Irtysh River has been a cause of friction between the three countries. The absence of transborder cooperation is not helping the situation either.

17. It’s not only China that has contributed to the Ob-Irtysh River pollution. Russia has also done a fair share of pollution, especially dumping of nuclear wastes. A case in point is the poor handling of the Mayak nuclear site.

18. The presence of oil fields in the river basin’s vicinity and the oil tankers plying the river has always been a disaster waiting to happen. There have been cases of accidental oil spills, triggering environmental concern.

19. The river basin region has a population of nine persons per square kilometer. However, there are large and high-populated cities around the river’s mineral resources on the southern watershed.

20. The Irtysh tributary is longer, but the Ob has more volume. The two rivers meet and turn sluggish and marshy at a town called Khanty Mansiysk. This town is named from the two dominant local indigenous groups.

Ob-Irytsh River – quick facts and statistics

NameThe Ob-Irtysh rivers
SourceAltai mountains
MouthGulf of Ob, Kara Sea
Length5,410 km (3,362 miles)
Direction of flowsouth to north
CountriesMongolia and China
Did you know?1. Irtysh is the chief tributary of the Ob and is also the longest tributary river in the world.
Note*The Irtysh, flows through Kazakhstan before reaching the Ob in Russia. The Ob begins on the border of Mongolia and Russia before winding its way north to the Arctic Ocean.
Table last updatedDecember 6, 2021

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