Creating visually consistent DEMs over water bodies using laser scanning data

The digital elevation model (DEM) is an invaluable product in numerous geospatial applications from orthorectification of aerial photographs to hydrological modelling and advanced 3D visualisation. With the current aerial laser scanning methods, superior quality digital elevation models can be produced over land areas, but surfaces over water bodies are visually problematic, especially for streams in 3D. We present a method to generate smooth, monotonically decreasing elevation surfaces over water bodies in DEMs. The method requires the point cloud data and the polygons delineating the water bodies as input data. We show how DEM visualisations improve by applying the presented method.