Based Optimal Highway Route Determination Between Baganakwo And Chanchaga Settlements In Niger State Nigeria

Abstract

Efficient highway alignment is critical for improving regional connectivity, reducing construction costs, and minimizing environmental and social impacts. In Niger State, Nigeria, rapid urban expansion and increasing traffic demand require data-driven approaches to route planning that go beyond traditional, intuition-based methods. This study aims to develop and demonstrate a Geographic Information System (GIS)–based framework for identifying an optimal highway route between Baganakwo and Chanchaga in the Bosso/Paikoro area of Niger State. The specific objectives are to integrate multiple spatial criteria relevant to highway design, generate least-cost route alternatives, and evaluate trade-offs among competing alignment options. High-resolution digital elevation models (DEM), land-cover data, soil and terrain stability proxies, existing road networks, hydrology, and socio-environmental constraints were incorporated into a composite cost surface using the Analytical Hierarchy Process (AHP) for criteria weighting. Least-cost path and corridor analyses were then performed to derive optimal and alternative highway alignments. The results identify an optimal corridor that balances route length and travel impedance while significantly reducing earthwork requirements, stream and wetland crossings, and potential social disruption. Sensitivity analysis demonstrates that while the shortest route is not necessarily the most cost-effective or least impactful, the selected alignment remains robust across reasonable variations in criteria weights. This study concludes that GIS-based multi-criteria least-cost path analysis provides a transparent, replicable, and effective decision-support tool for early-stage highway planning in data-limited environments. It is recommended that the proposed alignment be subjected to detailed field verification, geotechnical investigations, and phased engineering design. The workflow presented is transferable and can support corridor screening and sustainable highway planning in other parts of Nigeria and similar developing regions.