**Author details**

in centralised treatment plants for electricity production or as a fuel for public transportation. Technological advances, increasing scarcity of water and rising prices of fuel and fertilisers will soon make such techniques more affordable and competitive in low‐ and middle‐income

Urban sanitation is at an inflection point: although conventional sewer systems and large‐scale treatment plants are still seen as the golden standard, there is an increasing acknowledgement that sanitation systems such as faecal sludge management or decentralised/small‐scale systems are complementary options and constitute viable alternatives in the long run for selected parts of cities. The change in thinking, however, still has to reach all the city sanitation stakeholders to become a widespread and operating reality, from the urban leaders to the service providers and the engineers and consultants. The multi‐disciplinary nature of the new approaches makes them more complex than the engineering‐centric one. In order to reach full sanitation coverage in low‐and middle‐income countries, the sector should be enriched with the social and economic skills that are needed to involve the different sanitation stakeholders in planning

Although going beyond the current bottlenecks may seem daunting, it is possible to change the situation by creating the right incentives for the different stakeholders. The new paradigm advocated for in this chapter is in line with that: building interfaces, delegating management through arrangements which ensure benefits for all parties, increasing participation, thinking at scale and fostering better communication all contribute to reducing the sanitation burden of the governmental institutions and improving decision making, while increasing sanitation coverage and thus the consumer basis. There are ways to structure the sector through better governance, appropriate planning tools, the involvement of private stakeholders and innova‐

Sanitation has a key role to play in sustainable urbanisation, and it needs to be fully integrated in the current thinking about 'circular,' 'efficient,' 'green' or 'water‐secure' cities. Sanitation, as the supply chain for both used water and nutrients, is at the core of these urban sustainability concepts. Cities of the future will probably treat wastewater and sludge as close as possible to their source, to enable on‐site reuse of resources. Many pilot projects already go in this direction, by fostering grey water recycling in buildings and use of treated wastewater in urban gardening. In water‐scarce regions, there is a growing concern to plan wastewater treatment infrastructure so that it can directly contribute to groundwater recharge and safe water supply.

Integrating several sanitation systems under one roof, as has been outlined in this chapter is a first necessary step for successful sanitation coverage in rapidly urbanising cities. The better integration of sanitation in the 'urban ecosystem' is the promising second step, contributing to two of the main drivers of change: reducing the costs through better synergies among

services, while providing more incentives to the sanitation stakeholders.

processes and devise innovative management and financial schemes.

areas as well.

130 Sustainable Urbanization

**7. Conclusion**

tive financing mechanisms.

Philippe Reymond\* , Samuel Renggli and Christoph Lüthi

\*Address all correspondence to: philippe.reymond@eawag.ch

Eawag: Swiss Federal Institute of Aquatic Science and Technology, Duebendorf, Switzerland
