The Level of Water in Baikal: from One Extreme to the Other

The water level of Baikal has grown from 455.68 m above the Pacific Ocean up to 456.96 m over just five months: this is the maximum indicator of the lake’s water level (as of October 16). The most surprising thing is that even in the spring of this year none of the experts predicted such a sharp level increase (by 1.28 m).

The experts cautiously spoke about the return of water level to one of the values between the marks of 456 and 457 m which were established in 2001 as the maximum permissible limits for the fluctuations in the lake water level. By a strange coincidence, the former regulations that were for various reasons criticized by scientists, power engineers, and environmentalists, were replaced by new, more flexible rules in December 2017. Three different regulatory regimes were introduced for Lake Baikal, taking into account the current situation: if the year is dry, the level can be as low as 455.55 m, if the water content is average, the normal range varies between 456-457 m, and if the content of the water is high, the level of Baikal may exceed 457 m.

Reference: as of January 24, 2018, the water level in the lake was 456.08 meters, which is almost 20 centimeters lower than at the beginning of 2017.

The current year 2018 combines the features of different periods of water content: it started as one of the worst low-water years, and it is ending as one of the record years with the highest water content for the last 10-15 years.

The most surprising fact for interested observers who are not professional scientists is that the level rises continuously throughout the entire period after the ice has melted. It is usually said that the main source of water for Baikal is melting snow in coastal forests: if snow does not evaporate in the sun and manages to turn into water, and flows into rivers, then the spring flood fills the lake. Nevertheless, two diagrams on the website of the Limnological Institute of SB RAS smoothly diverge from each other beginning from about the middle of July, and as the time goes, the larger is the gap between the data of last year and current year.

There are three possible reasons for a decrease in the water level of Baikal regulated by the Irkutsk Hydroelectric Power Plant under normal conditions: provision of navigation, provision of water supply to the population and industrial enterprises, as well as generation of electricity. The navigation in the lower reaches of Angara stopped at the end of September; beginning from December 1 the navigation will stop along the entire length of the river - this question is solved. Now there will be no problems with water supply not only in the Irkutsk region, but also, probably, in Buryatia - its residents have complained about dry wells since 2014, now the lake level has risen almost to the limit set in the past. Electricity generation is regulated by the volumes of water passage established by the Yenisei Basin Water Management; here we can see the continuation of a strict policy of saving water resources: the Irkutsk Hydroelectric Power Plant operates at a minimum flow rate of 1300 cubic meters per second, Bratsk, Ust-Ilimsk and Boguchany HPPs operate at a modest expenditure of 2000-2400 cubic meters per second.

If no force majeure circumstances occur, in the winter of 2018-2019 the level of Baikal is unlikely to return beyond the “red line” of 456 m, so the lake will probably meet the next year in a rather good state. However, who knows: the lake made it clear once again that it is full of surprises.