Keywords: Kakhovka HPP Explosion, Dnipro River, average year discharge, height of the water surface

The full-scale invasion by the russian federation has significantly impacted the quantity and quality of water in the rivers located within the conflict zone. The explosion at the Kakhovka HPP was accompanied by the most catastrophic consequences for hydrological systems. Due to ongoing active military operations in the region of the disaster, direct measurements of water flow there are impossible. Therefore, in this study, the average year discharge of the Dnipro River for the year 2023 was calculated using computational methods. Therefore, the paper separately examined the flow of the Dnipro River for flow without Kakhovka HPP Explosion; and the actual flow in 2023. The lag time of the flow in the section between the Dnipro HPP and the Kakhovka HPP was determined through joint daily observations of water discharge in 1952 at the Dnipro HPP and Beryslav stations. Changes in the inside-year distribution of runoff were determined by comparing the actual average monthly water discharges of the Dnipro HPP with the normalized monthly discharge values of the Kakhovka HPP for the year 2023. An automated method for decoding satellite images was also used in the study to create a map showing the main stages of the desiccation of the former Kakhovka reservoir bed. Using automated satellite image interpretation, we created a map showing the main stages of dewatering of the bed of the former Kakhovka Reservoir. The difference between our calculated real flow in 2023 and the flow brought to conditions without dam blowing is water, that the Kakhovka Reservoir failed to retain could have been used for industrial and agricultural production, water supply and sewage, the normal functioning of nature reserves, tourism, water transport, and much more. All of these losses are very difficult to assess, but they definitely need to be recorded.

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