An Efficient Algorithm for Drainage Network Extraction on DEMs

Abstract This paper presents a new and efficient algorithm for extracting drainage networks on digital elevation models (DEMs), The algorithm is based on the simulation of a flow of water on the topographic surface, and it requires three steps. First, all irrelevant minima within the DEM are removed to ensure the continuity of streamlines. Second, flow directions are assigned to all pixels, plateaus included. Third, the contributing drainage area of each pixel is determined. Drainage networks are then extracted by thresholding the image for contributing drainage areas above a user-defined value. First-in-first-out queues of pixels ensure a fast implementation of all steps. The algorithm is presented as pseudo c code.