Optimising Integrated Solid Waste Management (ISWM) system under seasonal variations

Abstract Background The rapid urbanisation and change in consumption patterns have made Municipal Solid Waste (MSW) management a pressing global issue especially in developing countries including Ghana. The daily generation of waste is becoming a growing problem for the waste management system, especially Accra, the capital city of Ghana. This operational problem poses significant risks to public health and the environment. To address these issues, the study employs a linear optimisation model to develop and evaluate an Integrated Solid Waste Management system for the Accra Metropolitan Assembly area, utilising existing infrastructure. The model integrates informal waste pickers, acknowledging their socioeconomic role, and analyses the impact of seasonal waste variations (festive/non-festive periods for both dry and wet seasons). Results The analysis shows that integrating informal waste pickers greatly enhances the efficiency and resilience of the system by diverting waste from landfills (reduced from 250 to 40 tonnes/day during non-festive periods), which substantially reduces greenhouse gas emissions from transportation of MSW during festive periods and emissions from disposal sites. Though the inclusion of IWPs may result in increased operational costs, it also helps generate revenue from the sale of recovered materials and serves as a livelihood for the informal waste pickers. Conclusion This study concludes that formalising and integrating the informal waste sector is important for creating a sustainable and cost-effective ISWM system in Accra. The study also recommends that stakeholders and policymakers in Accra invest more in recycling and treatment facilities, strategically integrate IWPs, plan for seasonal waste surges, and optimise transportation to reduce the system’s environmental footprint.