SOLVING HYDROGEOLOGICAL PROBLEMS IN THE CONTEXT OF ASSESSING RESOURCE LOSSES AND THE FEASIBILITY OF RESTORATION OF THE KAKHOVKA RESERVOIR

The contradictory modern perspectives on the significance and role of the Kakhovka Reservoir in various sectors of Ukraine and the natural ecosystem necessitate the development of a systematic approach for a comprehensive assessment of the feasibility/infeasibility of its restoration. The general algorithm for such an approach may consist of sequential processing of the following stages: 1) comprehensive evaluation of long-term consequences and problems caused by the destruction of the reservoir dam (without assessing the relatively temporary consequences of the catastrophe itself); 2) assessment of the possibility of overcoming all problems that have arisen without restoring the reservoir and development of appropriate measures to address them; 3) comparison of the costs of these measures with the costs of restoring the reservoir and subsequent mitigation of negative effects from its existence; 4) objective comprehensive conclusion regarding the feasibility of reservoir restoration. The article also discusses hydrogeological assessments of filtration losses during reservoir filling and the depletion of artificial groundwater reserves after water discharge. The rates of backwater propagation (1956-1975) and groundwater runoff from the flood zone after the war crime committed by the occupiers in 2023 are compared. It is emphasized that reservoirs, especially large ones, are important factors in replenishing fresh groundwater resources and creating their artificial storage, as former local and sometimes regional groundwater discharge area transform into recharge areas. General features of formation and approaches to calculations of groundwater balance in reservoir influence zones are examined, as well as important specific features of hydrogeological conditions in the territory adjacent to the lower Dnipro.