A sustainable urban utopia – derived through a critical urban metabolism framework

Urban metabolism is a wide concept for examining the functions and performance of a city. It is particularly useful in connecting imperatives of resource sustainability and adaptability with the emergent properties of urban... [ view full abstract ]

Urban metabolism is a wide concept for examining the functions and performance of a city. It is particularly useful in connecting imperatives of resource sustainability and adaptability with the emergent properties of urban economic performance and quality of life. However, most discussions of urban metabolism remain concentrated on conceptual frameworks or delve into specific details of one aspect of the metabolism. Furthermore, the discussions tend to be solution oriented, assuming one solution to a problem or poorly categorizing the problem altogether. Bridging the gap between these discussions is important for achieving urban metabolism’s oft-stated potential as a useful tool for guiding urban design or planning.

This exploration made use of two vignettes of urban processes to frame discussion of emergent resource flow challenges as well as identified points of intervention. The two vignettes visualized: (i) the current, linear, organism-emulating, unsustainable and un-adaptive city form, and (ii) an idealized, perfectly cyclical, ecosystem-emulating, sustainable and adaptive city, a shift to which much of the sustainable cities and urban metabolism literature advocates. These vignettes were based on the context of Cape Town, South Africa, a coastal, water scarce and biodiverse area. In each vignette socio-ecological challenges were identified and a number of proposed interventions from literature are discussed. The examination of a sustainable urban ideal was not prescriptive, but meant to demonstrate the systemic nature of many of the challenges, which thus offers multiple approaches for addressing them. In this way a simple concept illustrates many multi-transitions from a relatively un-sustainable city towards a city which contributes to global sustainability.

The key findings suggest that the most drastic factor influencing urban resource consumption is society’s normative perception of waste, which demands that it be swept out of sight and out of mind. Addressing this perspective to change a squeamish understanding of waste and cultivate a society which values it, is perhaps the single most effective intervention for realizing a sustainable circular metabolism. Further, the intertwined nature of many resource systems in cities suggests that certain intervention points will have farther-reaching consequences. It is necessary for city practitioners to explicitly prioritize specific socio-ecological challenges in order to identify and mobilize capacity around certain interventions.