Conventional systems for urban sanitation and wastewater management in middle- and high-income countries

Abstract

The conventional sanitation system that has evolved in middle- and high-income countries is a waterborne system in which domestic and industrial waste is flushed away from the point of generation and treated off-site. These systems are designed to remove contaminants from wastewater in order to protect public health and the environment. The aim of this chapter is to provide an overview of design parameters and technologies used in conventional urban sanitation systems in middle- and high-income countries. It explains the composition of wastewater and the key contaminants that the system is designed to manage, including pathogens, suspended solids, nutrients, heavy metals, and chemical compounds. It also explains how the conventional sanitation system is designed to reduce and remove these contaminants along a service chain that includes the capture of wastewater at the household level as well as the collection, transport, treatment, and reuse/disposal. This chapter presents the dominant technologies that are used in middle- and high-income countries for each step in the sanitation service chain. Finally, it discusses the current trends in sanitation planning, including criteria for the design and selection of sustainable systems and principles that should guide us to more sustainable urban sanitation systems.