Route Alignment Planning for a New Road between Obligatory points using Geoinformatics Techniques: A Case Study in Dupcheshwor Rural Municipality, Nuwakot, Nepal

Abstract

This paper studies the geoinformatics techniques for selecting appropriate horizontal road alignment between
two obligatory points referred to as origin and destination considering various factors with multiple scenarios
under technical, environmental and combination of technical and environmental themes suitability perspective.
Specific objectives were to determine the factors responsible for road route alignment selection and to generate Least Cost Paths (LCPs) under several scenarios. A multi-criteria spatial based analysis was carried out
giving equal proportional weightage to each factors considered in the geo-database followed by a weighted
overlay to produce friction surface cost maps. Then LCP analysis was carried out to produce three route paths
considering technical factors only, environment factors only and combining both technical and environment
factors. LCPs thus generated were compared with each other with respect to their relative costs. Route
developed considering both technical and environment factors was found as the best one in this study in
terms of the relative cost. Furthermore, the new road route alignment, which is still alternative considering
technical and environment factors, was found if the mandatory control point is added between original origin
and destination points. This study suggests further research can be done for accurate and realistic automatic
optimization techniques and improvements for preliminary to detailed road alignment planning and design
coordination.