Integration of Multi-Criteria Decision Model, Analytic Hierarchy Process and Geographic Information System for Landfill Site Selection: An Overview of Varanasi City

Effective solid waste management is essential in urban areas. Despite efforts by local authorities in Indian cities to handle waste through various methods, landfilling remains the most convenient disposal method. This study aims to identify the optimal site for scientific landfilling in Varanasi City using a multi-criteria decision-making model, Analytical Hierarchy Process (AHP), and Geographic Information System (GIS). Initially, a comprehensive literature review, the Municipal Solid Waste Management Rule of 2016, and expert opinions were used to determine site selection criteria. Eleven criteria, including proximity to rivers or lakes, groundwater table, settlement proximity, and slope etc., were identified as crucial for landfill suitability. Experts assigned an appropriateness score to each criterion, ranging from 1 to 5, where 5 represented the best rating and 1 the lowest. As the criteria are not equally significant, weights were assigned based on their importance in decision-making using AHP. Criteria maps were prepared using ArcGIS 10.6.1, and a final map was generated through weighted overlay assessments. The investigation identified Khutahna (0.43 km2), Chhitauni (0.22 km2), Kakarhia (0.09 km2), and Kadi Chak (0.06 km2) as high-suitability zones for landfilling; Mustafabad (0.21 km2), Chandpur (0.15 km2), and Jalhupur (0.13 km2) as moderate-suitability zones; and the remaining section of the region as unsuitable. A site walkover is recommended to confirm the accuracy and suitability of the candidate locations.