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Lake Baikal: Earth’s deepest, oldest lake

Controversy surrounds construction of hydropower stations on a river that feeds deep, ancient Lake Baikal.

Lake Baikal photo by Alexey Trofimov Photographer, Traveler, photoguide on Baikal, Russian Geographical Society. View more photos from Alexey Trofimov.

Lake Baikal photo by Alexey Trofimov, photographer, traveler, photoguide on Baikal, Russian Geographical Society. View more photos from Alexey Trofimov.

Around 25 million years ago, a fissure opened in the Eurasian continent and gave birth Lake Baikal, now the deepest and oldest lake in the world. The lake is located near the Russian city of Irkutsk, one of the largest cities in Siberia with about half a million population. Like many of Earth’s waterways today, Lake Baikal may be in trouble. In early April, 2017, the World Bank held public hearings in Russia to discuss environmental impact studies around Lake Baikal in Russia, moving two mid-sized hydroelectric dams in Mongolia on Selenga River flowing into Lake Baikal another day closer to fruition.

Read an April 7, 2017 update on Lake Baikal, from Forbes.

Read a March 13, 2017 feature article on the Lake Baikal controvery, from the New York Times

A strongly worded Siberian Times article published on May 25, 2016 spoke of an earlier ecological assessment of Lake Baikal. That assessment led to dire warnings that this lake could suffer the same fate as the Aral Sea, formerly one of the four largest lakes in the world, now less than 10% of its original size after the rivers that fed it were diverted by Soviet irrigation projects.

Lake Baikal is currently a natural reservoir and a UNESCO world heritage site. It around 20% of the world’s unfrozen freshwater. According to the 2016 Siberian Times article:

Construction of … hydro power stations on the Selenga River and its tributaries can cause the unique lake to dry out.

The 25 million-year-old lake is on the edge of environmental catastrophe and if certain measures are not taken, it might disappear just like the Aral Sea.

Read the Siberia Times article about the construction of power stations on the Selenga River, one of Lake Baikal’s primary water sources.

In total, some 330 rivers and streams flow into Lake Baikal, some large like the Selenga and many small, while its main outflow is the Angara River.

Lake Baikal seen from space. Image via Provided by the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE.

Lake Baikal seen from space. Image via the SeaWiFS Project, NASA/Goddard Space Flight Center, and ORBIMAGE.

The Aral Sea in 1989 (l) and 2014 (r).  Image via Wikimedia Commons.

The Aral Sea in 1989 (l) and 2014 (r). Image via Wikimedia Commons.

What would be lost if Lake Baikal were to go the way of the Aral Sea? Holding 20% of all unfrozen surface fresh water on Earth, Lake Baikal is unlike other deep lakes in that it contains dissolved oxygen right down to the lake floor. That means creatures thrive at all depths in the lake.

Most of Lake Baikal’s 2,000-plus species of plants and animals are found nowhere else in the world. Scientists believe up to 40 per cent of the lake’s species haven’t been described yet. Species endemic to Lake Baikal have evolved over tens of thousands, perhaps millions, of years. They occupy ecological niches that were undisturbed, until the last few decades.

Lake Baikal’s rich and unique biodiversity includes species like the Baikal seal, also known as “nerpa.” It’s the only mammal indigenous to Lake Baikal.

The large freshwater seal indigenous to Lake Baikal, called a

The large freshwater seal indigenous to Lake Baikal, called a “nerpa.” Read more about the Lake Baikal seal at AskBaikal.

Scientists aren’t sure how these seals originally got into Lake Baikal. There are two primary hypotheses concerning this question, which you can read about here.

Another famous species native to Lake Baikal is the “omul,” a type of whitefish. It’s part of the Salmon family. This fish is the main product found at local fisheries. Due to overfishing, it was listed as an endangered species in 2004.

On the far right side of this map, just above Mongolia, do you see the large blue crescent? That's Lake Baikal. Map via Google.

On the far right side of this map, just above Mongolia, do you see the large blue crescent? That’s Lake Baikal. Map via Google.

Photo credit: Kyle Taylor

Photo credit: Kyle Taylor

Bottom line: Russia’s Lake Baikal – located in southern Siberia – is the world’s oldest and deepest lake. It provides a home for over 2,000 endemic species. Controversy surrounds construction of hydropower stations on a river that feeds the lake.

Daniela Breitman

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