Urban migration is a worldwide phenomenon, driven by economic prospects not possible in rural areas. The resulting population growth requires governments and urban planners to foresee and adapt the city infrastructure to cope with increasing demands. With restricted budgets, developing countries have to prioritize, often leaving waste management at the end. As protection of public health is one of the top priorities on low-income countries, a case can be made that sewage systems deserve more attention as part of a comprehensive waste management strategy. By describing the socioeconomic, technical and political factors of Vienna, Mexico City and São Paulo, this comparative investigation aims to highlight the evolution of sewage systems and solid waste management practices, demonstrating the stark differences in history that shaped their development. The subsequent literature review examines the potential health issues associated with multiple exposure pathways in the case of insufficient wastewater treatment and inadequate solid waste management. The quantitative analysis compares the potential emissions of nitrogen and total organic content via leachate migration from landfills and reemission of untreated wastewater into groundwater respectively. The literature review indicates that landfilling deserves special attention if groundwater quality is to be maintained. However, in light of the research, sewage collection and wastewater treatment are more important with respect to public health. Finally, the paper presents its conclusions and its implications for infrastructure planning in developing countries.