GIS-Integrated Analytical Hierarchy Process (AHP) for optimal landfill site selection in Kadoma City, Zimbabwe

Abstract

Effective waste management remains a pressing challenge in rapidly urbanizing cities like Kadoma, Zimbabwe, where limited land availability complicates landfill siting. Despite the global prevalence of landfilling, poor site selection in such contexts can trigger groundwater contamination, odour issues, and public health risks. This study addresses the absence of structured landfill siting research in data-scarce African cities by applying a GIS-integrated Analytical Hierarchy Process (AHP) and Multi-Criteria Evaluation (MCE). AHP was employed to assign relative weights to twelve spatial variables— including slope, elevation, proximity to rivers, roads, and built-up areas— through structured pairwise comparisons. MCE integrated these weighted factors within a GIS platform to generate a final suitability map. Results indicate that only 5.2 % of Kadoma’s area is suitable for landfill development, while the majority is constrained by dense urbanization. The suitability map, converted into a shapefile for visualization and area calculation, offers a practical tool for urban planners, environmental agencies, and local authorities to inform sustainable waste infrastructure development. This study demonstrates the applicability of GIS-AHP approaches in rapidly growing, resourcelimited urban environments and underscores the need for localized, data-driven decision- making in landfill site selection.