Landfill Site Selection Using GIS Based Multicriteria Evaluation Technique in Robe City, South Eastern Ethiopia

ABSTRACT Majority of inhabitants in most towns of Ethiopia often use unsafe solid waste disposal practices such as open dumping, burning, and burying. One of the most delicate steps in waste management is the selection of the most suitable landfill site, as multiple factors must be considered and there is no universal formula. Locating proper sites for solid waste disposal and selecting appropriate landfill sites far from residential areas, environmental resource settlement, and water are the main issues for the management of solid waste. Therefore, the objective of this study is to select landfill site Using GIS Based Multicriteria Evaluation Technique (MCE) in Robe City. So, the study used environmental and socio-economic factors or criteria for landfill site suitability in the study area. Soil, slope, elevation and land -use/land-cover are used as environmental factors and built-up, road used for socio-economic factors. The combination procedure follows the conventional scheme for GIS based MCDA. It involves three main steps. First, the criterion maps standardized or reclassified using spatial analysts reclassify tool. Thus, each factor has an equivalent measurement basis before any weight applied. Accordingly, all the factors used for this study reclassified into four suitability classes (S1, S2, S3, N1) with the range of values 1 to 4. The criterion weights automatically calculated once the pair-wise comparison matrix is entered in IDRISI-AHP weight derivation module and the criterion weight and the standardized criterion maps are combined/aggregated by means of weighted overlay technique analysis. The MCE model was evaluated through multiplying weights criteria and sub-criteria, and rates the criteria and the final suitability map will be generated from the result of this model in IDRISI 17 environment. The result shows that the challenges of solid waste management in the city, emphasizing the inadequacies of existing infrastructure, socio-economic factors, and institutional capacities. Due to a lack of designated and accessible landfill sites, inefficient waste collection methods predominantly relying on animal-powered equipment, and inadequate disposal practices leading to environmental and public health risks. The analysis reveals significant barriers, including insufficient funding, low private sector involvement, and limited institutional capacity, which contribute to the overall ineffectiveness of waste management systems. Finally, the result shows that about 4,136.01 hectares, or 16.92% of the total area is Not Suitable, in contrast, about 18,844.37 hectares (77.07%) of the area is Marginally Suitable classification covers and about 1,469.17 hectares (6.0%) is Moderately Suitable for land fill site. Therefore, through improving infrastructure, fostering community engagement, and enhancing training and resources to develop a comprehensive approach to solid waste management. 7