Comparing 1D and combined 1D/2D hydraulic simulations using high-resolution topographic data: a case study of the Koiliaris basin, GreeceComparing 1D and combined 1D/2D hydraulic simulations using high-resolution topographic data: a case study of the Koiliaris basin, Greece Peer-Reviewed Journal Publication Δημοσίευση σε Περιοδικό με Κριτές 2018-06-042017enThe development of high spatial resolution digital elevation models takes place via the use of GeoEye-1 stereo-pair imagery, providing highly accurate geometrical representations of complex riverine systems. The combination of geographic information systems with hydraulic models facilitates the exploitation of satellite topographic information throughout the cross-section extraction process. One-dimensional HEC-RAS and combined 1D/2D HEC-RAS models are adjusted by making use of the resulting high-resolution input. Several hydraulic simulations are effectuated in order to test how significantly DEM resolution affects hydraulic modelling results, with regard also to the model dimensionality. The ability of the combined 1D/2D model, based mainly on the high-accuracy input data, provides an accurate estimate of the flood hazard area. Flood-prone areas could take advantage of high-accuracy results and facilitate the effective management of extreme events and sufficient decision making.http://creativecommons.org/licenses/by/4.0/Hydrological Sciences Journal624642-656 Vozinaki Anthi-Eirini Βοζινακη Ανθη-Ειρηνη Morianou Giasemi Μοριανου Γιασεμη Alexakis Dimitrios Αλεξακης Δημητριος Tsanis Giannis Τσανης Γιαννης Taylor & Francis 1D HEC-RAS Combined 1D/2D HEC-RAS Extreme events Satellite stereo pair