GIS Platform for Multicriteria Evaluation of Route Alignments

Abstract

The selection of an appropriate alignment for a proposed highway is determined largely by relating topographic, urban, and environmental features to geometric design controls. Typically, aerial photographs and topographic, geologic, and soil maps are reviewed. In this paper, a geographic information system (GIS) platform that incorporates the main coverages needed for evaluating route alignments is described. Using the GIS and a geographically referenced database, a decision-aid tool for multicriteria evaluation of route alignments is developed. Possible alignments are evaluated based on community disruption and environmental, geotechnical, and geometric design criteria. The developed decision-aid tool integrates slope stability and roadway design packages and specifically written codes with GIS packages ARC/INFO and ArcView, the latter acting as the system engine and interface. A case study is presented that applies the developed platform to the testing of potential alignments for a proposed 12 km highway to the south of the city of Beirut, Lebanon. Results of the case study demonstrated the advantages of the decision-aid tool and highlighted its potential in providing a quick, multicriteria screening evaluation of possible route alignments.