Ecological Systems and Devices Annotation << Back Hazardous Hydrological Phenomena in the Moscow Region Petrova E.G. This article examines the hazards and risks of hazardous hydrological phenomena in the Moscow region. It analyzes the frequency and impacts of severe floods and snow melt floods in the region from the 14th century to the present. Throughout history, catastrophic floods have been observed here many times, causing significant damage, injuries, and even casualties. The risk of flooding is due to the location of many settlements in the region, economic facilities and agricultural lands in low-lying areas in river valleys. In recent years, the danger and risk of severe rain and thaw-rain floods has increased in the Moscow region, which is associated with ongoing climate change and an increase in the frequency and intensity of heavy rainfall. The danger of floods for the population and economy is greatest due to their suddenness and extreme nature. Keywords: flood; rain flood; snow melt flood; hazard; risk; extreme precipitation. DOI: 10.25791/esip.4.2026.1588 Pp. 36-44.