GIS Modeling for an Optimal Road Route Location: Case Study of Moiben-Kapcherop-Kitale Road

Abstract

The choice of a route location is a detailed activity that involves evaluation of different factors in order to attain optimal location. Roads are major projects and therefore need to be located to ensure seamless connectivity, which should be optimal. The objective of this research study was to perform spatial modeling using GIS analysis and weighting criterions using Analytical Hierarchical Process to make site selection for an optimum road. To attain optimal road route location, satellite image of the study area was acquired and the image processed and reclassified to obtain baseline data of the area including the land use land cover map. A Geodatabase was created to allow integration with GIS analysis. GIS database included Shapefiles of soils, existing roads, towns, rivers, and vegetation, noise and dust surveys. Questionnaires administered to various experts were processed to give weights derived using Analytical Hierarchical Process (AHP). The weights from different criterions gave unique normalized Eigen vectors in each category. The weights were applied in the development of a model to obtain an optimum route. From the findings factors that were given high considerations were topographical and physical features, which included slope, vegetation and existing rivers. This was followed by infrastructure, environment and lastly soils according to the weights derived. Two routes from the analysis were realized which were optimal and differed from the original route proposed for the project. The implications of these findings therefore showed that embracement of GIS with integration of different sources of data and remote sensing and analysis using AHP technique should be adopted as a tool and system for a project of similar approach in Kenya.