The article is devoted to developing an universal methodological apparatus of ecological monitoring and practical assessment of the state of hydroecosystems to determine the nature of the anthropogenic impact. The authors analyzed the transformation of the Desenka River channel (Kyiv, Ukraine) in the 1965 – 2021 years. The primary attention is paid to changes in the coastline of Kyiv to determine the nature of the anthropogenic impact on the study area. The authors improved the technology of monitoring the dynamics of the water regime of the riverbed by constructing bathymetric maps based on the results of hydroacoustic measurements and the space imagery interpretation.The complex use of methods for selecting and processing information was applied through the use of GIS technologies (thematic classification of remote sensing results in the conditions of data exchange of ground-based verifications with independent features of objects). The results are presented in a way that is easy to interpret. It was found that the main reason for the change in area is sand mining. The bathymetric survey allowed to specify the maximum depth of the reservoir, which is 16.8 m. It was determined that the relief of the bottom is typical for a quarry. The river's depth in its central part increases from west to east in proportion to the increase in the width of the reservoir. The study found that sand was mined in the same place, washing away huge underwater quarries and forming numerous silt alluviums. According to the results of the analysis of changes in areas presented in this study, the authors proved that uncontrolled sand mining has a negative impact on the biotic stability of landscapes and causes irreparable damage to the environment. The effectiveness of remote sensing methods for determining the ecological status of hydroecosystems is proved. The presented studies indicate the need to stabilize the ecological balance of the river ecosystem, take appropriate measures to increase the productivity of hydrolandscapes, improve the environment and ensure the environmental safety of the Desenka River and coastal areas.