Landfill site suitability analysis using AHP for solid waste management in the Guwahati Metropolitan Area, India

Landfilling is a convenient method to tackle waste problems, in developing as well as developed countries. Determining a minimally environmentally deleterious garbage dump site is a challenge considering that a bevy of socio-economic, environmental and legal parameters often exists in developing countries. Guwahati is a city in India that faces the hindrance of not having a suitable landfill site. The existing landfill site, Boragaon, does not fulfil the prescribed parameters listed by the Central Public Health Environment and Engineering Organisation (CPHEEO) and the Central Pollution Control Board (CPCB). The main objective of this study was to provide alternative sites in the Guwahati Metropolitan Area (GMA) using geographic information systems (GIS) and multi-criteria decision analysis (MCDA)-based analytic hierarchy process (AHP) methods. Seven criteria were considered in site selection. These were land use, slope, elevation and proximity to wetlands, rivers, roads and the airport. Results indicate that 7.5% of the area was most suitable, 22.8% highly suitable, 43.8%, 22.2% and 3.6% areas were of moderate, low and least suitability respectively. On the basis of the area covered by each location, 5 landfill sites were identified to potentially relocate the existing site. The study highlights the problem of waste management in low- and middle-income cities.