Assessment of the causes of the Kakhovka HPP dam collapse based on a comprehensive analysis of structural monitoring, seismic, and infrasound studies

This study presents a comprehensive assessment of the Kakhovka Hydroelectric Power Plant (HPP) dam collapse (Ukraine) through integrated analysis of structural monitoring, InSAR, seismic, and infrasound data. Long-term geodetic observations (1995–2021) indicate vertical displacements of concrete structures ≤ − 2 mm/year and horizontal shifts within ±12 mm, consistent with seasonal patterns and insufficient to compromise structural stability. Ground monitoring ceased after 2021 due to armed conflict. To extend the record, 104 Sentinel-1 images (2020−2023) processed with DInSAR revealed vertical rates up to −13 mm/year, consistent with geodetic data. Seismic and infrasound data recorded during the collapse constrain the timing, location, and nature of the source. Seismic P-wave arrivals indicate a shallow local event on 5 June 2023 at 23:34:50 UTC (46.783°N, 33.364°E), while infrasound arrays estimate an epicenter at 46.659°N, 33.534°E, with <19 km discrepancy. High signal-to-noise ratio and clear seismic onset are consistent with an explosive origin. Integration of structural, seismic, and infrasound observations indicates that progressive deformation and hydrostatic loading alone cannot explain the failure. The collapse is consistent with a high-energy explosive event (estimated 767–914 ± 170 kg TNT). This study highlights the value of multi-sensor forensic assessment for large-scale hydraulic infrastructure failures under conflict conditions. • Multisource geodetic, seismic, and infrasound data were analyzed to assess the Kakhovka dam failure. • Long-term geodetic and MT-/DInSAR observations revealed no critical vertical or horizontal displacements prior to collapse. • Seismic records on 5 June 2023 at 23:34:50 UTC indicate a localized impulsive event consistent with an explosion. • Infrasound arrays confirm the explosive nature of the event, estimating a yield of 914 ± 170 kg TNT. • Integrated evidence supports an externally induced explosive origin rather than deformation-related structural failure.