A methodology for aligning raster flow direction data with photogrammetrically mapped hydrology

A popular method to increase the accuracy of extracted watershed boundaries is to utilize that hydrology network to post-condition the digital elevation model, thus ensuring the local topography honours the stream network. This process is known as stream burning. This paper outlines an alternative approach to accomplish a similar objective. The outlined approach unambiguously translates the topological relationships within the vector hydrology layers directly into a raster flow direction grid. Initial testing of this methodology has shown several accuracy and processing advantages for extracting watershed boundaries.