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The built environment requires extraction and consumption of enormous quantities of raw materials, water, and energy. While these materials remain in use for several years or decades, growing global populations and aging infrastructure are driving widespread generation of one of the largest and most challenging waste streams to manage. There is growing interest from communities in integrating circular economy (CE) strategies in the context of construction & demolition (C&D) material management. Many approaches for doing so focus on small-scale CE applications like individual products, materials, or projects. However, greater understanding is needed at the city-scale given communities’ complex position at the frontlines of local development, resource consumption, and waste management. This study summarizes the development of an evaluative framework for community-based C&D circularity at a city or regional level. The framework expands upon a mixed methods approach called the Circularity Assessment Protocol (CAP), which integrates aspects of urban metabolism, geospatial analysis, and qualitative research methods to examine plastic waste management in communities. To advance convergent CE research, here, we aim to adapt the CAP framework to C&D. We describe our adaptation of the CAP to C&D through a conceptual review describing research, methods, and strategies related to seven elements of a local CE context: C&D Analytics, Building Material and Design, Community, Use, Collection, End-of-Cycle, and C&D Emissions. This work describes a novel yet preliminary conceptualization for developing a baseline understanding of circular C&D material management and a holistic examination of barriers, affordances, and opportunities for improving city-wide circularity.
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Site Resource Inventories – a Missing Link in the Circular City's Information Flow
Abstract. A circular city builds upon the principles of circular economy, which keyconcepts of reduce, reuse, recycle, and recover lead to a coupling ofresources: products and by-products of one production process become theinput of another one, often in local vicinity. However, sources, types andavailable quantities of underutilised resources in cities are currently notwell documented. Therefore, there is a missing link in the information flowof the circular city between potential users and site-specific data. Toclose this gap, this study introduces the concept of a site resourceinventory in conjunction with a new information model that can manage thedata needed for advancing the circular city. A core taxonomy of terms isestablished as the foundation for the information model: the circulareconomy is defined as a network of circular economy entities which areregarded as black boxes and connected by their material and energy inputsand outputs. This study proposes a site resource inventory, which is acollection of infrastructural and building-specific parameters that assessthe suitability of urban sites for a specific circular economy entity. Aninformation model is developed to manage the data that allows the entitiesto effectively organise the allocation and use of resources within thecircular city and its material and energy flows. The application of thisinformation model was demonstrated by comparing the demand and availabilityof required alternative resources (e.g. greywater) at a hypothetical sitecomprising a commercial aquaponic facility (synergistic coupling of fish andvegetables production) and a residential building. For the implementation ofthe information model a proposal is made which uses the publicly availablegeodata infrastructure of OpenStreetMap and adopts its tag system tooperationalise the integration of circular economy data by introducing newtags. A site resource inventory has the potential to bring togetherinformation needs and it is thus intended to support companies when makingtheir business location decisions or to support local authorities in theplanning process.
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- Award ID(s):
- 1832213
- PAR ID:
- 10371716
- Date Published:
- Journal Name:
- Advances in Geosciences
- Volume:
- 54
- ISSN:
- 1680-7359
- Page Range / eLocation ID:
- 23 to 32
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.5194/adgeo-54-23-2020
