Flood modelling using airborne lidar data: An example of Ulus River

Floods are occurring in almost every part of the world, causing loss of life and great economic lost. In order to reduce and eliminate the impact of floods on human life and their properties, the factors that cause flooding need to be properly investigated and the water depth, velocity and impact forces of floods must be accurately mapped. Therefore, the production of flood hydraulic models is one of the leading works in the production of flood hazard maps and in determining the measures to be taken. DEM and DSM are used to represent the surface topography of the river bed form and floodplain. Within the scope of the work to obtain DEM and DSM, data was obtained by airborne LiDAR system within the area where the Ulus District in the center of Bartın Province, which is located on Ulus River. From this data, high resolution (25 cm) DEM and DSM were produced through the airborne LiDAR point cloud to reveal the effect of topography, buildings and trees, one of the main factors that affect the accuracy of flood hydraulic models. Using the hypothetic flow data created, 2D flood hydraulic models were produced using DEM and DSM in different details, comparing the effects of water level and spread in the floodplain. Keywords: flood modelling, airborne LiDAR, Ulus River, DEM, DSM, singular tree trunks.