Site Suitability Analysis for Waste to Energy Facility in Onitsha North Local Government Area, Anambra State, Nigeria

Abstract

Onitsha North Local Government Area (LGA) in Anambra State is an industrial and commercial city in south eastern Nigeria that is currently facing serious environmental problems resulting from poor solid waste management system. Also, the city is experiencing poor electricity supply at a time of increasing energy demand for domestic and industrial activities. The rate of solid waste generation in the city has increased with rapid urbanisation, population growth and economic expansion. Exploiting the energy potentials of the huge amount of waste generated in the area through Waste to Energy (WtE) technology is an efficient and sustainable waste management strategy that can be deployed in order to boost the energy supply mix in the area. However, the viability of WtE adoption has not been investigated in the study area. As a first and critical step in that direction, this study combined Geographic Information System (GIS) and Multicriteria Decision Analysis (MCDA) techniques to identify suitable sites for WtE facility in Onitsha North with a view to determining the viability of adopting WtE in the area. The factors used for multicriteria evaluation are Land use/Land cover, distance from road, distance from surface water, distance from existing dumpsite and slope. The Analytic Hierarchy Process (AHP) was used to assign relative weights to these factors. The Weighted Overlay method was used to integrate these factors in ArcGIS environment to produce suitability map for WtE facility in the study area. Results showed that less than 1% and 77% of the study area were found to be moderately suitable and marginally suitable respectively for siting WtE facility; while 21% and 0.33% of the study area were found to be less suitable and not suitable respectively. The study has provided the basic information required for harnessing waste energy potential for sustainable development in Onitsha North. The waste energy potentials can be exploited to provide alternative energy source for industrialisation and economic activities in the area. The WtE will also serve as an alternative efficient waste management strategy in the study area. The combination of GIS and MCDA techniques has proven to be efficient in site suitability analysis, hence it can be applied in solving multicriteria decision problems.