Solid Waste Disposal Site Selection Using GIS-Based Multi-Criteria Decision Analysis Techniques: A Case Study in Areka Town, Wolaita Zone, Ethiopia

The landfill method is recognized as the cheapest and most widely used solid waste management system. However, improper disposal of solid waste is a serious problem in urban areas of Ethiopia like Areka town due to the rapid growth of population and urbanization. The objective of this study is to identify suitable landfill sites for solid waste using geospatial-based multi-criteria decision analysis techniques. To achieve this objective data were collected from field observations, focus group discussions, key informant interviews, residential areas, protected areas, elevation, slope, and roads were used to identify suitable landfill sites. ArcGIS, QGIS, and Erdas Imagine software were used to prepare the criteria maps. The analytical hierarchy process was also applied to derive the relative weights of criteria maps and then the weighted overlay tool was applied for the preparation of the final suitability map. Accordingly, 5%, 60.1%, 32.8%, and 2.1% of the study area was not, less, moderate, and highly suitable for solid waste disposal. The final result shows that Landfill 1 (4.9 ha) and Landfill 2(6.6 ha) were the 1st and 2nd most suitable sites for proposing a new landfill with the least negative impact on the environment and human health. Thus, this study strongly recommends town municipality should use proposed landfill sites 1 and 2 for solid waste disposal and future studies should also consider various factors overlooked in this study.