Multi-criteria analysis of municipal solid waste treatment technologies to support decision-making in Kisumu, Kenya

The directive to close the dumpsite in Kisumu, Kenya has made the search for alternative solid waste treatment and disposal technologies urgent. The aim of this research is to support the decision-making process by analyzing multiple socioeconomic and environmental parameters of salient solid waste treatment options. We used multi-criteria analysis to assess and compare anaerobic digestion, sanitary landfill, bioreactor landfill, and incineration. Informed by field observations and interviews, the chosen assessment criteria were economic costs, electricity generation, GHG emissions, land footprint, air pollution, soil and water contamination, and compatibility with recycling efforts. A literature review yielded quantitative and qualitative data that supported the analysis and the ranking of solutions according to performance in each criterion. Our analysis shows that anaerobic digestion is a suitable solution for Kisumu, due to its reduced environmental impacts, production of electricity and fertilizer, suitability to treat the large organic waste stream generated in the city, and compatibility with independent recycling activities. Landfilling represents a cheap solution; however, previous failed initiatives indicate that finding available land close to main waste generators is a challenge. Incineration is costly and requires advanced air quality control equipment and high combustibility of incoming waste, which is not the case for Kisumu, where over 60% of waste stream is organic/wet. Our results and recommendations are targeted for the Kisumu case, but they can be relevant for researchers and policymakers elsewhere, especially in low- and middle-income cities facing similar challenges.