RIVER BED AND FLOODPLAIN OF THE DNIEPER WITHIN THE KAKHOVKA RESERVOIR: BEFORE ITS CONSTRUCTION AND AFTER THE DAM BLOW UP IN 2023

The breach of the Kakhovka Reservoir dam resulted in one of the largest technological environmental disasters of the 20th and 21st centuries, with no parallels worldwide. After a sudden drop in water levels within the reservoir, the floodplain and the course of the Dnipro River, which had been submerged for 68 years, were exposed. Based on available information, including topographic maps predating the reservoir inundation, as well as accessible imagery from Sentinel-2 L2A after the dam's breach, a comparative analysis of the morphology of the riverbed and floodplain microrelief was conducted. The research revealed that during the 68 years underwater, there were no alterations to the riverbed or floodplain microrelief. This phenomenon is primarily explained by the absence of alluvial material inflow due to the presence of an upstream cascade of reservoirs on the Dnipro River. The reservoir mainly received very fine suspended particles, leading to their minimal accumulation at the reservoir's bottom without disrupting the natural morphology of the riverbed and floodplain microrelief. The natural course of the Dnipro River, the floodplain microrelief, and the islands, including their channels and ancient riverbeds, became the main water flow concentrators when the water level in the reservoir decreased to the level of the floodplain after its destruction.