Hydrological Modeling for Determining Flooded Land from Unmanned Aerial Vehicle Images—Case Study at the Dniester River

In recent decades, in the Pre-Carpathian region of Ukraine during summer period, floods and flood events became more frequent. They were accompanied by significant economic environmental loss. Especially powerful 2008 2020, but 2014 2016 also had destructive consequences. Therefore, study river channel processes, stability assessment flooded land areas due to is an urgent problem. The aim propose a methodology for hydrological modeling sections riverbeds with complex morphometric characteristics. construction digital elevation model (DEM) selection distance between cross-sections, as well determination Manning coefficients, have greatest impact on accuracy modeling, so these factors should be given maximum weight when calibrating model. object was section Dniester River place transition from foothill part hilly–marshy meandering shifts river. includes three principal components: DEM, type underlying surface level water rise riverbed. research carried out basis imaging unmanned aerial vehicles (UAVs). 2017, riverbed period vegetation growth, which affected determining heights points. According results this imaging, residual mean square (RMS) points exceeded permissible value RMS (0.25–0.3 m) two times. 2021, performed autumn there no leaf cover. DEM 2021 0.26 m. survey 2017 orthophotoplans created, used determine planned displacements bed clarify characterize roughness surface. obtained graph date 24 June 2020 according hydrometeorological station located near selected area. result using HEC-RAS module site characteristics rise. It established that order achieve required leafless year, since constructing decreases half growing season. On orthophoto plans, refined coefficients developed, allows taking into account changes area calculated based flood.