ASSESSMENT OF FLOOD DEVELOPMENT DUE TO THE DESTRUCTION OF DAMS

Since the beginning of hostilities in the Ukraine territory, there have been several cases of detonation of dams on reservoirs. These events affected the surrounding areas, leading to a flood of different degrees. One of the significant cases occurred on the dam covering the Irpin river, close to Kyiv. It was built during the Kyiv Reservoir filling to prevent the flooding of the river valley and serves as a bridge. After a part of the dam was broken, water from the Reservoir began to fill the Irpin river. The flood threatened Demidiv and settlements further along the river valley. The study aims to determine the areas and volumes affected by water from the Reservoir, estimated material losses and the development of dangerous engineering and geological processes using remote sensing data. The method of identifying water bodies and, in general, bodies with a certain degree of hydration (vegetation, rivers, lakes, moistened soils) based on many spectral images consists of the calculation of Normalized Differential Water Indices. The water index was calculated from the green and near-infrared bands of space images from the Landsat 8-9 mission in the period from February 24 to April 30. The volume of water that formed the flood was calculated. For this, a digital terrain model was built based on the ALOS PALSAR space image, where each pixel of GeoTiff contains the height value. The flooded area is 16.5 square kilometres per month. The deposits of the first and second on the floodplain terraces, composed of uneven-grained sands, were flooded. The development of engineering-geological processes and the engineering protection of settlements are analyzed. The most common threats are flooding and swamping, erosional and gravitational processes are not observed.