Circular Urban Metabolism as a Design Approach for Masterplans
Future cities are challenged with the task of reducing resource demands and GHG emissions, and all the while providing populations a good quality of life and the opportunities necessary for their economies to be productive. One approach to deal with these complexities during the early stages of city design is known as “circular urban metabolism” (CM). CM considers an urban region to function as an interdependent system, where “the output of one [agent] is the input of another” (Robinson et al., 2003). Agents include natural resources, human knowledge, labor, skills, income, technology and data.
The problem is that there are few CM precedents globally, and current urban planning practice does not make CM fundamental to design decision making. The research questions were: where (intervention points) and how (analytical methods) do we intervene in current design practice to achieve CM outcomes on masterplan projects? The aim of the dissertation was to produce a framework that could inform design using a CM approach. The methodology was the application of explanatory logic to three masterplans as case studies, and structured interviews with urban practitioners to test the framework. The result was the Circular Settlements framework (Circuset), which identified seven intervention points: context and site analysis, land uses, operations, zoning, urban morphology and building design. The analytical methods were based on systems mapping and evaluation against a circularity score that consisted of five indicators: loop-closing, “symbiosis” (Except, 2009), resource efficiency, self-sufficiency (Rapoport, 2011) and CO2 emissions. Interviewees expressed the framework would be easy to integrate in the current planning workflow, however would require significant training needs and its implementation would incur high costs. The practical implication is the integration of CM in masterplan decisions, particularly on private-sector projects. Further research needs are to develop bespoke tools for Circuset’s analytical methods, and implement it on a new masterplan project.