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Abstrakt

The presented article presents a hydrological analysis of the extreme flood in September 2024 in the experimental catchments of the Slučí, Sokolí and Suchý brook, which are right-hand tributaries of the Černá Opava River. The interruption of monitoring and morphological changes in the riverbeds in these catchments due to the destruction of water-gauging stations forced the reconstruction of the flood using mathematical models, which is generally an obvious fact for the Jeseníky region with the greater or lesser meaning. The rainfall-runoff models HYDROG, HEC-HMS, MIKE SHE, SIMWE and the hydraulic models HEC-RAS and DHI MIKE were used for this analysis. The Mnichov hydrological station on the Černá Opava was chosen as the calibration profile. The causal precipitation belongs among the absolute measured records in the stations in several locations in the Jeseníky Mountains, and the propagation of the flood further down the Opava catchment represented an absolute maximum in the measured water level and evaluated flow for some stations. The situation was not different in the catchments of the Slučí, Sokolí and Suchý brook. The analyses also included a comparison of the results of individual rainfall-runoff models and the methods they implement, e.g. SCS-CN, Horton or Green-Ampt. The simulated hydrographs show good correlation between the measured and evaluated data, with the Nash-Sutcliffe coefficient not falling below 0.7, mostly due to the declining part of the flood hydrograph, when standard rainfall-runoff models are unable to simulate the slowdown of runoff due to water accumulation in inundation areas. For this and other reasons, it is appropriate to use a combination of rainfall-runoff and hydraulic models.