Integration of Multicriteria Decision Analysis and GIS for Evaluating the Site Suitability for the Landfill in Hargeisa City and Its Environs, Somaliland

Abstract

Poor waste management and illegal waste shipments adversely affect the environment and public health, resulting in environmental degradation. Indeed, environmental degradation is one of the most visible problems in Hargeisa. Currently, solid waste is disposed of at two dumping sites within the city limits, causing problematic and unsanitary conditions. Moreover, the existing dumpsites are on the verge of closure, highlighting an important need that must be addressed. This research aimed to integrate multicriteria decision analysis and GIS to evaluate the site suitability for landfill in Hargeisa, Somaliland. For this purpose, eleven significant parameters were selected: proximity to built-up areas, surface water, groundwater well points, sensitive sites (airports), land use/land cover, geology, soil type, elevation, slopes, roads, and separation from existing dumpsites. Next, these were combined via an analytical hierarchy technique. Subsequently, restriction buffer analysis was performed on the seven parameters to obtain better and more accurate results, and restricted zones were omitted. Furthermore, the pair-wise comparison used to obtain priorities between the selected criteria showed that the LULC is the most significant criterion in the model, with a relative weight of 0.1829, followed by habitations, with 0.1506. The overall result reveals that approximately 68.96% (21,060.9 ha) of the study area is unsuitable, while 24.36% (7441.53 ha) and 6.68% were considered less and highly appropriate zones, respectively. As a result, this study reveals that despite the vast extent of the study area, the areas ideal for landfill remain severely limited. Therefore, in light of the findings of this study, the municipal council of Hargeisa must reevaluate dumpsite locations and waste management practices to address the issues in the region in a timely manner. Furthermore, this systematic research approach will assist regional and global researchers, policymakers, and municipal governments.