The current urban population of 3.3 billion is expected to reach 5 billion by 2030. This urbanisation of
the global population is equally an urbanisation of poverty. Cities concentrate people, huge volumes of
excreta and nutrients from vast areas of farmland into a limited area. For the urban poor in particular,
these accumulations result in major health problems and a low standard of living. In recent decades
sanitation practitioners and researchers have been working on modern sanitation systems that address
two related urban problems the
waste and the food production problem. The approaches developed are
usually considered under the term ecological sanitation (ecosan) and are based on recognising the value
of nutrients as part of a sustainable wastewater management system. Two large-scale
projects from the
Philippines and Burkina Faso, are presented to illustrate the benefit to the urban poor offered by
affordable ecosan alternatives in
terms of sanitation and fertiliser production