Policy Papers

The Reuse Opportunity // Cities Seizing the Reuse Opportunity in a Circular Economy

This report argues that decisive, urgent and large-scale action is needed to dramatically increase wastewater treatment, reuse and recycling. The report states that cities, as drivers of the global economy, must lead this resource revolution to enable a transition to a circular economy.

Wastewater is a global problem. Today, around 80% of all wastewater is discharged untreated into rivers, lakes and oceans. It creates health and environmental hazards, and contributes to Greenhouse Gas emissions, including nitrous oxide and methane. These emissions are three times larger than those produced by conventional wastewater treatment activities. Recovering water, energy, nutrients and other precious materials embedded in wastewater is an opportunity for cities to transition to the circular economy and contribute to improved water security.


  • Aqaba: A mid-size city turning its “zero discharge” challenge into a good opportunity
  • Bangkok: Using sludge as a resource and a valuable economic good
  • Beijing: Building infrastructure to keep up with an ever expanding mega city
  • Chennai: Addressing water scarcity through accelerated wastewater reuse
  • Durban: Wastewater as an economic good
  • Kampala: Protecting its water source with an integrated plan to control, treat and reuse wastewater and septic sludge
  • Lima: Learning by doing under the urgency of shrinking glaciers
  • Manila: A mega city regenerating its resources through wastewater treatment and reuse


IWA website


February 2018


International Water Association IWA

IWA Programmes establish change agendas on key themes for a water-wise world that contribute to sustainable development; these programmes are: Basins of the Future, Cities of the Future and Water and Sanitation Services. In shaping and furthering these agendas, IWA engages with a variety of individuals and organisations through projects, events and publications.

in partnership with

OPEC Fund for International Development OFID

OFID is an intergovernmental development finance institution established in 1976 by member states of the Organisation of the Petroleum Exporting Countries (OPEC) as a collective channel of aid to developing countries. Working in cooperation with country partners and the international donor community, OFID aims to stimulate economic growth and alleviate poverty by providing financing to build basic infrastructure, boost delivery of social services and promote productivity, competitiveness and trade. Realising the vital role clean water plays in fighting poverty, OFID is supporting operations that range from large-scale sanitation and water supply systems to village pumps and school latrines, to schemes rationalising water use in arid regions, and rehabilitating and expanding irrigation systems. Our vision is a world where Sustainable Development, centered on human capacity building, is a reality for all. Our mission is to foster South-South Partnership with fellow developing countries worldwide to eradicate poverty.

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Research Papers, Publications and Books

The Global Food-Energy-Water Nexus

By Paolo D'Odorico, Kyle Frankel Davis, Lorenzo Rosa, Joel A. Carr, Davide Chiarelli, Jampel Dell'Angelo, Jessica Gephart, Graham K. MacDonald, David A. Seekell, Samir Suweis, Maria Cristina Rulli. Water availability is a major factor constraining humanity's ability to meet the future food and energy needs of a growing and increasingly affluent human population. Water plays an important role in the production of energy, including renewable energy sources and the extraction of unconventional...

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Nexus Project Bolivia // Working together to develop the water, energy and food security sectors

The contradictory development objectives for water, energy and food security in Bolivia generate conflicts of interest between ministries, and also between authorities and institutions in the provinces and municipalities: each institution wants to support especially its sector, be it water, energy or rural. For this reason, planning is needed that transcends different sectors, such as that sought by governments at the national and local levels.

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Le Barrage de Fomi // Potentiel pour Un Projet d’Intérêt Commun

Par Luca Ferrini & Lucia Benavides. Cet article explique comment le projet de barrage de Fomi, qui a récemment regagné le monumentum, marque une grande opportunité d'intégrer l'approche Nexus dans le processus de planification comme un outil d'aide à la décision. Situé en Haute Guinée, à la tête du bassin du Niger et dans une zone aride affectée par le changement climatique et l'insécurité, la construction du barrage de Fomi poserait à la fois de nombreux risques et défis ainsi que des...

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