Municipal Solid Waste Disposal Site Selection Using GIS Based Multi Criteria Decision Analysis Techniques in Mandi Town, West Wollega Zone, Ethiopia

Landfilling continues to be the most economical solution for managing solid waste around the world. Nonetheless, in fast-growing Mandi Town, poor waste management presents serious difficulties. This research primarily aims to explore appropriate landfill locations by utilizing geospatial multi-criteria decision analysis (MCDA) using satellite data, taking into account environmental, social, and economic dimensions. Information was also gathered through site assessments, FGDs (n = 4), KIIs (n = 12), published and unpublished materials. Factors such as distance from rivers, land use and land cover (LULC), soil characteristics, elevation, geology, slope, and transportation infrastructure were analyzed using ArcGIS 10.8, IDRIS Selva, Erdas Imagine, and Microsoft Excel. The Analytic Hierarchy Process (AHP) was utilized to assign weights to each criterion, followed by a weighted overlay method to create the ultimate suitability map. The results indicate that waste management in Mandi Town is poorly executed, with 41.6% of waste disposed of unlawfully and 25% incinerated. The suitability evaluation showed that 11.4% (388.4 ha) of the area is deemed unsuitable, 37.7% (1292.4 ha) is categorized as less suitable, 37.5% (1285.8 ha) is classified as moderately suitable, and 13.4% (459.9 ha) is considered highly suitable for landfill establishment. FGDs and KII results show solid waste is discarded in open areas, roads, rivers, and ditches, it becomes a serious challenge to Mandi. These findings can be utilized by urban planners, environmental managers, and policymakers to address waste management systems. The research suggests moving forward with the proposed sites and advocates for further studies that include wider socio-economic and ecological factors.