The attention of the whole world is riveted on the Zaporozhye nuclear power plant, which Putin has held hostage in his unmotivated large-scale aggression against Ukraine. But there are also hydroelectric power plants, in whose reservoirs huge amounts of water have been accumulated.. Do they pose a \?

We are talking, in particular, about the Kakhovskaya hydroelectric power station, located in the temporarily occupied territory.. What happens if the dam is destroyed? And in general, how and what structure controls the operation of Ukrainian hydroelectric power plants? With these and other questions ZN. UA appealed to the Deputy General Director of PJSC " Unfortunately, in wartime conditions, given the restrictions associated with ensuring the security of facilities, our interlocutor was unable to share all the information.

— Bogdan Leonidovich, is there any generation at the Kakhovskaya HPP, located in the temporarily occupied territory

- Now the station is operating with three units out of six - this is 30-40% of the capacity. Since the Kakhovskaya HPP is located in the temporarily occupied territory, it cannot be used to balance the energy system and provide ancillary services.. Also, we cannot deliver spare parts there in order to carry out repairs and prepare for the autumn-winter period..

Nevertheless, today the Kakhovskaya HPP operates according to the daily schedules of electricity production.. It also provides average daily ecological water flows to the lower [blink title\u003d" The upper pool is upstream, the lower pool is on the other side of the hydraulic structure. The headwater is often a reservoir. [/blink] - at least 500 m? /s, which corresponds to the rules for the operation of the reservoirs of the Dnieper cascade and the decisions of the interdepartmental commission under the State Agency for Water Resources of Ukraine.

- Is there a threat of destruction of the Kakhovka dam as a result of hostilities? What are the consequences of its destruction

- Unfortunately, in a war it is very difficult to predict some of the consequences. However, we believe in the Armed Forces of Ukraine and, for our part, are also taking all possible measures to ensure the maximum safety of the population.. Kakhovskaya HPP can operate for a long time if there is no external interference in its activities, shelling of power lines, substations, destruction of equipment.

— But if the Kakhovskaya HPP suddenly stops?

- There will be no catastrophe for the adjacent territories and the population: the water will pass through the spillway dam, so neither the dam break nor shallowing will happen.

— Not so long ago, you reported about the problem of low water at the Dniester hydroelectric power station. What is the situation at other hydroelectric power plants and reservoirs, in particular, the Dnieper basin?

— As of August 1, the flow of the Dnieper River near Kyiv was 790 m? /With. For 25 days of August, the inflow decreased by more than 210 m? /s, which is below the average for this period of the year. Unfortunately, according to the short-term forecast of the Ukrhydrometeorological center, a further decrease in the inflow of water to the Dnieper and Desna rivers is expected.. On most rivers of the Kyiv region and tributaries of the Middle Dnieper, low and very low water content is observed.. These are the realities....

— The head of the department of the Research Institute of Nature Management and Ecology of the National Academy of Sciences of Ukraine Vasily Andreev, in an interview with the media, claimed that dams kill rivers, in particular the Dnieper basin. He said that “rivers must flow”, otherwise salinization of surface waters and siltation of reservoirs will occur, as well as a decrease in recharge by the small rivers of the Dnieper. In particular, the salinity of the water in the lower reaches of the Dnieper is already close to the salinity of the water of the Sea of \u200b\u200bAzov.. Do you agree with him?

– Water salinity is constantly monitored by relevant organizations. So, according to the study, the mineralization of the water of the Kakhovka reservoir does not change significantly and averages about 0.40 g/dm? , according to the worst indicators, mineralization can increase up to 0.60–0.80 mg/dm? These concentrations are almost unchanged in different water content years.. For comparison, the mineralization of the Sea of \u200b\u200bAzov reaches 10–15 g/dm? But, indeed, the waters of the tributaries of the Kakhovka reservoir - Konka, Tomakovka and Bazavluk - are more mineralized, this figure reaches 3 g / dm? But these tributaries have an insignificant annual flow (from 0.04 to 0.8 km? ) and, in comparison with the main watercourse, cannot have a significant impact on the degree of mineralization of the water of the Kakhovka Reservoir.

— Please specify how close the regime of water flows through the reservoirs of the Dnieper cascade is to the natural flow?

— After the creation of a cascade of reservoirs, the ecologically minimal water flow in the downstream of the Kakhovskaya HPP is 500 m? /With. At the same time, under natural conditions, the minimum flow rate would be only about 200 m? /With. With such an insignificant natural flow in summer and autumn, salt water from the Black Sea would constantly enter the river at the mouth of the Dnieper. It would penetrate tens of kilometers upstream and reach the water intake facilities of cities. So just without the reservoirs of the Dnieper cascade, the risk of salinization of the lower reaches of the river would be much higher. This indicates the importance of observing the release regime of the Kakhovskaya HPP, especially in conditions of low water supply..

- What can happen if suddenly the water release regime is violated?

- As I said, this is a threat of salt water penetration into the lower reaches of the Dnieper. It also leads to a decrease in the content of dissolved oxygen in the water, an increase in the content of hydrogen sulfide, fish kill, soil salinization and other things..

– How noticeable is the impact of climate change on the health of our rivers, in particular, the Dnieper?

– In 2018, by order of Ukrhydroenergo, special studies were carried out to assess the probability of penetration of a salty wedge into the lower reaches of the Dnieper. The results obtained showed that under modern conditions, the probable scale of its penetration into the lower reaches of the Dnieper has slightly increased compared to the 80s of the last century.. This is due to global climate change - a reduction in the inflow of fresh water and an increase in the influence of sea water on the mouth section of the Dnieper due to sea level rise.. In accordance with the recommendations of scientists, an environmentally sound mode of operation of the Kakhovka hydroelectric complex has been developed. Its reconstruction and expansion are the most realistic measures to improve the hydrological conditions for the functioning of ecosystems in the lower reaches of the Dnieper.

— What form of ownership of Ukrhydroenergo?

The largest hydro-generating company in Ukraine "

The company includes ten stations on the Dnieper and Dniester rivers - Kyiv HPP, Kyiv HPS, Kanevskaya HPP, Kremenchugskaya HPP, Sredneprovskaya HPP, Dneprovskaya HPP-1 and Dniprovskaya HPP-2, Kakhovskaya HPP, Dniester HPP, Dniester HPP. Kanevskaya PSPP and Kakhovskaya HPP-2 are in the process of preparation for construction.

By the beginning of 2022, the total number of hydroelectric units at the company's stations is 104, and their total installed capacity has reached 6,208.3 MW.