Bridge and infrastructure damages following the September 2024 floods in the Czech Republic: post-disaster field survey

This study investigates the catastrophic September 2024 flood in the Czech Republic, focusing on its impact on bridge infrastructure. Through a comprehensive methodology integrating field surveys, geospatial analysis, hydraulic data, photographic evidence, and damage analysis, the study assesses the extent of damage and the challenges posed by the flooding. To empirically quantify the observed damage, damage state (DS) thresholds—derived from various sources—are introduced to standardize the assessment process. These thresholds are then integrated with documented bridge performance along with photographic evidence. The findings reveal that of the 122 investigated bridges, 41 were not functional, 20 of which experienced total collapse.

Scour, debris impact and accumulation, inadequate hydraulic openings with complete washout, and embankment failures are identified as primary failure mechanisms. In addition, DSs assigned from post-event unmanned aerial vehicle (UAV) orthophoto maps are compared against ground-truth field classifications, showing 73.3% agreement on the assigned DS and 93.3% agreement on the serviceability classification. By providing empirical damage data, photographic documentation, and analysis of critical factors affecting bridge resilience, this research offers a valuable resource for engineers, policymakers, and urban planners aiming to design more resilient infrastructure and prevent transportation network disruptions.