Deriving New Minimum Cost Pathways from Existing Paths

Without a priori cell traversing cost data, conventional GIS-based techniques cannot be used to find minimum cost paths from specified starting points to specified ending points. However, in one class of problems where these costs do not exist a priori, it may be possible to derive them. This class of problems is characterized by the presence of an existing minimum cost path that is subject to the same traversing cost mechanics as the new path that is being contemplated. This study developed and evaluated linear programming-based techniques for deriving both isotropic and anisotropic traversing costs from existing minimum cost pathways. The derived costs can then be used to find minimum cost routes for new pathways that are subject to the same cost mechanics as the existing pathways. The techniques presented here were evaluated by applying them to situations found in the forest road network of the Arapaho and Roosevelt National Forests (ARNF) in Colorado. In 18 of the 19 situations evaluated, the predicted routes generated using the techniques presented here agreed with actual roads found in the ARNF.