Optimized landfill site selection for municipal solid waste by integrating GIS and multicriteria decision analysis (MCDA) technique, Hossana town, southern Ethiopia

Abstract

Improper solid waste disposal has remained the major bottleneck for the socio-economic development particularly in urban and peri-urban areas of Ethiopia. This study was conducted with the prime aim of identifying an optimum municipal solid waste (MSW) management option subsequently selecting the best landfill site in Hossana town using integrated geographical information systems (GIS) and multicriteria decision analysis (MCDA) techniques. Accordingly, GIS integrated with MCDA was used to analyze the relative weight of each criterion and the overall suitability map where ten criteria were considered within their respective constraints. To create a landfill suitability index, environmental and socioeconomic factors such as distance from settlement, land use and land cover, lineament, slope, road, and wind direction/aspect were weighted. Population growth, waste generation rate, and waste volume/year were used to calculate the required landfill size. The study finding revealed that the town's MSW generation rate was 0.45 kg/cap/day, which was within the range of most of Ethiopian urban areas. On the other hand, the total daily and annual MSW generation was found to be 79.58 and 29,047 tonnes, respectively. Moreover, the study's findings revealed that 20.8 % of the solid waste was found was recyclable and the remaining 79.20 % was non-recyclable. Considering the future trend of waste generation, 19 ha of land in the city's Northern and Southern outskirts was chosen as a candidate landfill site with all the necessary suitability analysis. Therefore, optimized landfill site selection and better management system of MSW in urban and peri-urban areas could be achieved by the conjunctive application of MCDA and GIS.