Digital Elevation Model (DEM) is an important component in flood inundation modelling as a part of flood risk analysis. However, Digital Surface Model (DSM) which still contains noises of artefacts is more common to be available than DEM. Then DSM misleads the inundation extent. This study will evaluate a measure to obtain a bare-earth surface (DEM) by developing and applying a workflow to remove the noises from DSM using simple tools available in the GIS computer software. The output of the method will then be used as input for flood inundation modelling of Semarang City in Indonesia. In addition to the main data set of TerraSAR-X DSM provided by Indonesia Geospatial Information Agency (Badan Informasi Geospasial or BIG), two sets of open source digital elevation data from Shuttle Radar Topography Mission (SRTM) and Advanced Spaceborne Thermal Emission (ASTER) are included in this study. The three data sets are processed and quantitatively compared. The results show that the applied noise removal method must be traded off with the lower resolution. Hence, the level of detail of particular flood inundation modelling will determine the required DEM resolution. Different study purposes will lead to different appropriate DEM resolutions to be used.

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General risk management standard, e.g. ISO 31000:2009, approaches risk as a coin with a pair of two sides, i.e. the threat and the opportunity. However, it is hardly the case of flood events which mainly come as threats. Despite the contrary, this study explores the potential applicability of the available risk management standards specifically for flood. It then also synthesizes the components to result a framework for allocating resources among various strategies to result the optimum flood risk reduction. In order to review its applicability, the framework is then reviewed using several historic flood risk reduction cases. Its results are qualitatively discussed and summarized including the possible improvement of the framework for further applications. @en