Siting MSW landfills on Lesvos island with a GIS-based methodology

The siting of Municipal Solid Waste (MSW) landfills in Greece is a difficult process due to land resource limitations, the country's mountainous, insular and primarily water permeable terrain as well as an exacerbated public opposition (NIMBY syndrome). A GIS-based methodology is presented here with the goal to identify and rank the candidate landfill sites for the entire island of Lesvos. The initial step of the methodology comprises a GIS-based spatial analysis that uses 10 criteria, by excluding all areas unsuitable for any waste disposal activity. The pre-selected areas are then further assessed by fieldwork and candidate landfill sites are determined. The candidate sites are ranked using 19 criteria with predefined weight coefficients on a 0 to 10 grading scale. The weight coefficients are estimated for each criterion using the Analytic Hierarchy Process (AHP), while the grading scheme is based on pre-defined guidelines. An overall suitability index is produced for each candidate site allowing comparison and best case selection. A case study for the island of Lesvos is presented here, in which eight candidate landfill sites were finally selected and ranked. Social factors highly determined the ultimate selection of the site in Lesvos, since the third rather than the first site suggested by the methodology, was finally approved by local authorities.