The value of the Circular Economy of Waste Water


In this paper - based on interviews with Dutch experts - we present the creation of the Energy & Raw Materials Factory (ERMF) of the Dutch Water Authorities, also known as the Resource Factory, as one of the solutions to this global challenge of water in the circular economy. Resources like cellulose, bioplastics, phosphate, alginate-like exopolymers from aerobic granular sludge (bio-ALE), and biomass can be recovered. Bio-ALE is an alginate-like polymer of sugars and proteins and can be used in agriculture and horticulture, the paper industry, medical, and construction industries. The ERMF demands significant investments but the return on investment is high both from a financial and environmental perspective, provided that markets can be realized.


1. The ERMF enables the recovery of clean water, cellulose, bioplastics, phosphate, bio-ALE, and biogas from municipal wastewater. The value of the recovered resources including the reduction of maintenance cost in the Netherlands is estimated at €233 million per year from 2030. This is approximately €14 per person per year. Similar investments are needed to create ERMFs.

2. Assuming that all the necessary investments for ERMFs are provided and the revenues of €14 per person per year are extrapolated to a global population of 7 billion people, the total revenues will be about €100 billion per year. The ambitions articulated in the Sustainable Development Goals (SDGs) on water and sanitation of the UN have recently been estimated at US $114 billion per year up to 2030 by the World Bank. The circular economy (introduction of ERMF at global scale) and the UN SDGs on water and sanitation provide potential win-win’s.

3. Collective activities have to be developed to create markets and to sell the recovered resources in order to prevent unwanted competition between water authorities. The realization of the ERMF demands a long-term strategy, i.e., a long lead time, significant financial resources, and continuous attention from all stakeholders.

4. Cross-institutional collaboration and communication is fundamental. We found that stable collaborative networks, alignment between research and practice, and well-established monitoring and evaluation, are important conditions that increase the long-term capacity to establish and further develop the recovery of resources from wastewater.

5. There are commercial opportunities for companies that are active in the engineering of water treatment installations. They can play an important role in creating Resource Factories, both at the national, European, and global level.

This publication with my colleagues Stef Koop, Kees Roest and Eli de Vries in Environmental Management can be found here


The development of the ERMF is based on a long-term vision and implementation process and predictions have been provided about the revenues. In the framework of this article several interviews took place with knowledgeable experts in this field. A special word of thanks is necessary for the collaboration and input from the following experts: Ir. Johan van Alphen (Tauw Consultancy), Prof. Dr. Ir. Cees Buisman (Wageningen University), Ir. Ben Geurts (Counselor Prime Minister, The Hague), Drs. Sanne de Groot (Tauw Consultancy), Drs. Enna Klaversma (Waternet and ERMF, Amsterdam), Prof. Dr. Ir. Mark van Loosdrecht (Technical University of Delft), Ir. Kees van der Lugt (Waternet Amsterdam), Ing. Chris Reijken (Waternet Amsterdam), Ir. Paul Roeleveld (Royal Haskoning DHV, Amersfoort), Ir. Ruud Schemen (Association of Water Boards of the Netherlands), Ir. Andre Struker (Waternet Amsterdam), Mr. Albert Vermue (General Director Dutch Water Authorities, The Hague), Drs. Herman Walthaus (Ministry of Infrastructure and Water Management, The Hague). Part of this research was funded by the POWER project. The European Commission is acknowledged for Funding POWER in H2020-Water under Grant Agreement No. 687809.

Dick Bouman's picture

Dear Kees van Leeuwen,

Happy to read about these new developments in the Netherlands around the recovery of resources from waste. You have posted this at our VIA Water Platform. Could you elaborate more on what this could mean for the context of cities in Africa; and/or how our partners could elaborate on this idea. We have several projects that have taken at least a piece of the Factory model (e.g. in Nakuru/Pot2Product and in Accra/SafiSana).

Kees van Leeuwen's picture

Good question. The answer required some time, but the answer is summarized in our latest E-Brochure vs 9 of March 2018. This Brochure with links can be found on our City Blueprint website (click on documents): and also attached here. In the E-Brochure you will see that we did a cluster analysis of 45 cities in 2015. It shows cities in a variety of stages to become water-wise, displayed on the worldmap with different coloured dots (see also our review). Rather than going from cities lacking basic water services   to wasteful cities and then to water-efficient cities and another step to resource-efficient and adaptive cities,  and finally to water-wise cities, cities should make long-term plans and leapfrog to the stages that they can afford. If needed supported by the World Bank or other financial institutions. This will save a lot of money. You also need to combine water with the other challenges in cities (see review; Figure 5 and Table 2).

On the technical aspects, KWR Watercycle Research Institute is very much involved in water technology research. One of the new plans is to radically change the way we treat waste water. Increasing urbanisation is leading to a growing demand for water, materials and energy in the affected areas. In a circular economy, water, (raw) materials and energy are recovered and reused/recycled. The Allied Waters UPcycles Collab focuses on the recovery and (re)use of residuals generated in the urban watercycle. The recovered compounds are made available to the market for applications in various economic sectors.   So, here is not only the focus on the residuals but also on the water itself. As cities are massively wasting water, reuse of water  can be a very great solution for African cities. See: Hope this addresses your question!