Probably, it is not very important for nature. The academician Galaziy wrote about it in his book “Lake Baikal in Questions and Answers”, sayingthat the source of the Angara regularly froze during the ice age and then water runoff completely stopped. Other scientists are confident that Baikal has changed many times during its existence, and in recent times (judging by geological standards) there was a period when the lake level was by 50 meters lower than the current one! Some endemics, probably, went extinct due to that fact, but the lake’s ecosystem has survived. However, the level of water in Lake Baikal has been steadily declining over the last 500 years.
The answer to the question of regulating the level is unambiguously important for the people living on the coast of the lake. And the main concern is not about decrease, but about increase: many people have built houses, piers, tourist centers in the coastal zone. Not all of them, maybe, are entirely legal, since the construction was conducted in the water protection zone. But there are also villages on Lake Baikal that were built in times when no environmental legislation existed at all. If the water level rises quickly and sharply, significant damage will be inflicted upon coastal settlements, roads, power transmission lines and other facilities.
The matter of regulation of the Baikal water level is extremely important for everybody living not only on the banks of the Angara River, but also in Siberia. The most densely populated cities in the Irkutsk Oblast (including Irkutsk, Angarsk, Shelekhov, etc.) receive drinking and technical water from Angara, and the cascade made up by four hydroelectric power plants on this river produces about 50 billion kilowatt-hours of electricity per year, or about 25% of electricity production in the entire interconnected energy system of Siberia. At the same time, the Angara branch of the cascade is hydrologically interconnected with the Yenisey branch, which means that competent regulation of the operation of HPPs in Siberia is extremely important: hydropower industry in this macroregion is on par with with thermal generation.
“The large share of HPPs constituting the bulk of generating capacities of the interconnected energy system of Siberia makes it possible for them to perform a range of system-wide functions. Alongside with the annual production of tens of billions of kilowatt-hours of electricity, they cover almost the entire variable part of the load charts, regulate the frequency, bear the bulk of loading and emergency capacity reserves. Besides, Irkutsk and Bratsk hydropower plants possess unique reservoirs of long-term regulation and carry out one more function that has no analogues in the global hydropower industry: they ensure the balance of production and consumption of electricity throughout the interconnected energy system of Siberia from year to year. That is, they are regulators of annual energy balances” - the Irkutsk Scientist Vladimir Savelyev wrote in his book titled “Modern Problems and the Future of Hydropower Industry in Siberia”.
It was easier to close the Baikalsk Pulp and Paper Mill than to remove the damage done by it to Lake Baikal.
International Day for Monuments and Sites is celebrated worldwide on April 18. Baikal has more than 300 objects of this kind. We will tell you about the most important of them.
Answering the most common question: why fluctuations in the water level influence the lake ecology and could it be harmful to Baikal.