Rethinking Sustainable Sanitation for the Urban Domain

Climate change, diminishing natural resources and rural-urban demographic trends will have profound impacts on future urban infrastructure delivery in both developed and developing countries. These challenges will however, leverage new opportunities for circular urban economies in which productive sanitation will play an important role in both the North and South. In the developed world, the challenge is to initiate a transition from disposal oriented, water-based infrastructure regimes towards more sustainable, re-use oriented, and productive sanitation. Decentralized approaches to “productive sanitation” (including the production of biogas, fertilizer or water for irrigation) with a source-separation focus (segregation of flow streams with different properties) will allow for considerable cost and resource savings and enable life-cycle economies. In the developing world, the sanitation challenge is about leapfrogging over-engineered sanitation services and technologies, especially for urban areas which are currently without sanitation services, to overcome the huge service backlog. This paper gives an initial overview of the current state of urban sanitation with a North- South perspective, followed by a discussion of the new role of sustainable sanitation systems for cities of the future. Planning innovations for urban sanitation, initial lessons learned and current challenges faced are addressed. Context specific challenges and opportunities are illustrated in a variety of urban settings, from non-tenured, low-income settlements to middle- and high-income inner-city areas.