Geospatial technologies and multi-criteria decision making based-urban solid waste disposal suitable site selection: The case of Assosa town, Ethiopia

Abstract

Solid waste is a byproduct of human activity in urban areas. The generation of solid waste have been increasing in urban areas due to the increasing population and socio-economic development in the urban areas. As such, solid waste management is the most difficult task that many developing and developed countries are facing. Solid waste management using landfill techniques is always required for the sustainable management of solid waste. However, selecting suitable landfill site is challenging as it requires multiple factors from multiple sources. Moreover, a comprehensive approach that considered multiple environmental, social and economic factors and per capita solid waste generation rate is not well known. The objective of this study was to select an economically viable, environmentally sound, and socially acceptable solid waste disposal site for the Assosa municipality using the state-of-the-art-geospatial technologies and multi-criteria approach. The main dataset criteria used for this study include proximity from road, slope, elevation, proximity from surface water, proximity from airport, proximity from fault, geology formation, proximity from groundwater point, groundwater depth, proximity to settlement, soil types, proximity from environmental protected areas, land use/land cover, and wind direction. In addition, interview questioners, and field observations were also used as an auxiliary data source. All the factors were evaluated pertinent to their suitability for landfill sites and weights were assigned for each factor using analytical hierarchy process (AHP) and multi-criteria decision making was used to produce solid waste suitability map for the Assossa town. Accordingly, the result showed that about 9.5 km² (8 %) of the study areas was highly suitable, 18 km² (18 %) was moderately suitable, and 79.5 km² (74 %) of the study area was unsuitable for solid waste landfill. The study results further showed that suitable sites for solid waste dumping are located in the northwestern parts of the town. Generally, the study showed that an integrated geospatial technologies and multi-criteria approaches are efficient and effective for selecting suitable solid waste disposal sites that have minimum environmental risk and human health concerns.