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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 is the source of ongoing controversies, as developers move into the area. The primary threat is from Mongolian power companies who, with help from the World Bank, are looking to build two hydroelectric dams near Lake Baikal. The dams would water from the Selenga River, which helps feed the lake. In early April, 2017, the World Bank held public hearings in Russia to discuss environmental impact studies related to this project, bringing it another day closer to fruition.

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. According to the 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 an April 7, 2017 update on Lake Baikal, from Forbes.

Read a March 13, 2017 update on Lake Baikal, from the New York Times

And the hydroelectric dams aren’t the only development being considered in the area near the lake. In a May 4, 2017 article in Global Times, senior executives from a Beijing-based natural drinking water company discussed plans to start construction of a bottled water factory near the lake, despite reported petitions from local residents opposing the project. The company said the project will not cause damage to the local ecology, as some Russian media reports have claimed.

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.

Lake Baikal is currently a natural reservoir and a UNESCO world heritage site. It contains around 20% of the world’s unfrozen freshwater. In total, some 330 rivers and streams flow into Lake Baikal, some large like the Selenga and many small. Its main outflow is the Angara River. The water in the lake is said to be crystal clear, and some claim it has magical, mystical power.

What would be lost in the extreme case if – hypothetically – Lake Baikal were to go the way of the Aral Sea? Holding one-fifth of Earth’s unfrozen fresh water, 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.

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.

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. In fact, 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. Local economies around Lake Baikal depend on this fish; it’s 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.

The April 7, 2017 article in Forbes said that environmental groups near Lake Baikal prefer building wind and solar farms in the Gobi desert to hydroelectric dams near Lake Baikal. When speaking of the threat to the lake from the dams, the article said the world is paying scant attention to environmental issues on this remote lake, despite its uniqueness. The article quoted Arthur Alibekov, leader of a UN-based expert taskforce on hydro power, who said:

Baikal as we know it will cease to exist but very few seem to care. As long as the rest of the world sees it all as just a Mongolia-Russia squabble, Baikal is in danger.

Unfortunately, we are too far from California to find a Hollywood-star champion.

Photo credit: Kyle Taylor

Lake Baikal, via Flickr user 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.

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