Small water and wastewater systems: pathways to sustainable development?

Globally we are faced with billions of people without access to safe water and adequate sanitation. These are generally located in developing communities. Even in developed communities the current large scale systems for supplying water, collecting wastewater and treating it are not environmentally sustainable, because it is difficult to close the cycle of water and nutrients. This paper discusses the advantages of small scale water and wastewater systems in overcoming the difficulties in providing water and wastewater systems in developing communities and in achieving sustainability in both developed and developing communities. Particular attention is given to technology and technology choice, even though technology alone does not provide the complete answer. Disadvantages of small scale systems and how they may be overcome are discussed.