"CityLoops - Closing the loop for urban material flows" is a EU Horizon2020 project with 28 partners. (Official project website:

CityLoops brings together six ambitious European cities to demonstrate a series of innovative tools and urban planning approaches, aimed at closing the loops of urban material flows and increasing their regenerative capacity. Demonstration actions will be implemented in relation to construction/demolition waste, including soil, and organic waste. During the inception phase, a circular city scan methodology and indicators will be developed and implemented in each city, by adapting current MFA and Urban Metabolism methods to include context-specific data and challenges, to adjust planned demonstration actions, provide an evaluation framework for the measures and monitor their progress towards a circular economy. A series of further innovative decision support tools will be developed (such as City Lab, a GIS based city planning tool, and a pre-demolition resource-mapping tool) for specific demonstration actions. In each city, a Local Stakeholder Partnership will be established at project outset, involving citizen groups, businesses communities, and other relevant partners, to guide planning and implementation. In each case, public procurement actions will also be analysed to assess potential supportive measures. As the selected cities are small to medium sized cities (pop. 50,000 – 600,000), Apeldoorn, Bodø, Mikkeli, Porto, Seville and Roskilde/Høje-Taastrup, the tools, approaches and solutions demonstrated should be replicable in a large number of cities across Europe. Replication is embedded throughout the project. At city level, all demonstration cities will prepare scale-up plans. At a regional level Collaborative Learning Networks will be established, consisting of other municipalities, public bodies, and other relevant regional institutions, to prepare regional upscaling plans. At a European level, a series of Replication Zones will be recruited over the course of the project to prepare replication plans. Guidance on replication will also be produced.

The overarching objective of the CityLoops project is... develop, implement, and replicate a series of innovative urban planning approaches and instruments, aimed at facilitating closing the loops of urban material and resource flows and promoting the transition to a circular economy (CE), thereby reducing the environmental footprint, increasing regenerative capacities, and stimulating new business opportunities and job creation in European cities.

Metabolism of Cities' involvement

Three Metabolism of Cities team members, Aristide Athanassiadis, Carolin Bellstedt and Guus Hoekman are currently working on this project and are leaders of WP4. Paul Hoekman was previously involved too, specifically in Task 4.1 and 4.2. Within that working package, they are responsible for:

  • Task 4.1 – Literature review (M1 – 3), where a thorough review of existing accounting methodologies used in research projects, academic literature, urban metabolism studies commissioned by cities was carried out.
  • Task 4.2 – Development of a Flow and Stock database structure (M3 – 6), which will be the layout which cities will use to input their data for accounting their flows and stocks (at a sector- and city-level). This layout will also be used for uploading data to the open source data repository.
  • Task 4.3 – Sector-Wide Circularity Assessment (SCA) (M3 – 12). During the Inception phase, a Sector-Wide Material Flow and Stock Accounting (MFSA) method was developed. It was implemented in each city within WPs 2 & 3 in the form of courses.
  • Task 4.4 –Urban Circularity Assessment (M12 – 24) - under development
  • Task 4.5 – Circularity hotspot analysis (M24 – 36)
  • Task 4.6 – Develop open source data repository and circularity monitoring platform (M24 – 48)

The specific project objectives are

  • To develop a series of innovative procedures, approaches and open access and open source tools designed to facilitate and embed circularity within planning and decision making processes for the following material flows, specifically focusing on: organic waste (OW), and construction/demolition  waste (CDW) including soil.
  • To demonstrate and evaluate these innovative approaches in a series of ambitious demonstration programmes of innovative solutions in six small-to-medium sized European cities, under a continuous monitoring and optimisation framework, in terms of a) the measurable reduction of materials use and waste generation, natural resource consumption and their associated environmental footprint, and b) the measurable increase of the regenerative capacity of the demonstration areas in terms of material and natural resource creation.
  • To develop an urban circularity assessment (UCA) methodology, to be piloted in each city, based on Material Flow and Stock Analysis Accounting (MFSA) methodologies and stakeholder mapping, adapted to meet the needs and contexts of small to medium sized cities, designed to pinpoint  circularity hotspots, facilitate the embedding of circularity into public planning and decision making processes, as well as providing a city circularity monitoring framework and dashboard. The circular assessment methodology and tools developed will all be open source and the data collected and  used will be open access to facilitate their reuse and transferability.
  • To develop, in collaboration with external European stakeholders, a definition and overarching behavioural, economic and environmental indicator set for circularity in the urban context, as well as a set of demonstration measure specific sub-indicators.
  • To instigate innovative stakeholder engagement processes in each city, in relation to the different flows addressed, designed to promote collaboration with civil society, the business community, academia and public authority stakeholders, intended to promote stakeholder buy-in and co-operation, the  identification and promotion of business opportunities, the development of coherent and flexible regulatory and policy frameworks and innovative governance structures, and the establishment of stakeholder networks.
  • To exploit the potential of public procurement activities and processes to support the demonstration activities, by requiring the consideration of circularity in public contracts, and replicating these at local and regional levels in order to encourage and accelerate markets for circular products and services.
  • To instigate the upscaling and replication of the measures, tools and platforms demonstrated at the city, region and European level, through a series of capacity building activities at each level.
  • To engage with other relevant projects, initiatives, programmes and networks to promote replication and experience exchange, most notably the Global Covenant of Mayors for Climate and Energy, as well as other related projects funded under the Horizon 2020 programme.



Go to project website

Related locations


Team members

The following people from Metabolism of Cities are involved in this project.


Related News

CityLoops Deliverable #4 is here - The Urban Circularity Assessment Method June 1, 2022
10 Sector-Wide Circularity Assessments are completed for CityLoops March 31, 2022
Literature Review on urban material flows and stocks accounting = First CityLoops deliverable D4.1 March 23, 2020
Starting our first EU Horizon 2020 project: CityLoops Oct. 1, 2019