Least cost path analysis for water diversion routes in high-altitude mountain area

Abstract

This paper describes a method to find a least-cost path for water diversion planning in the high-altitude mountain area by using the GIS techniques. However, existing algorithms could not be used for practical water diversion projects in the China's southwest region. To improve conventional cost path analysis, we first use the heuristic algorithm to build a three-dimensional elevation surface model based on the gradient elevation distribution along water diversion routes. From this, we create a cost surface of water diversion project in a raster data format by means of DEM data, and identify the best water diversion path by including the presence of energy dissipation stations and consideration of critical barriers where water diversion routes intersected with the densely inhabitant area. Subsequently, we suggest an evaluation of three-dimensional elevation surface error, and present the ratio of the area enclosed by both the machine-aided route and the artificial-designing route and the length of the designing route as a measure to evaluate the accuracy of the least-cost path of water diversion route.