THE CIRCULARITY IMPERATIVE

We use resources and services faster than nature can regenerate them. In 2021, the ecological footprint of humans equalled some 1.7 Earths. The fact that we take too much, too quickly, is clearly a problem. Another problem is the fact that we fail to adequately manage or value the waste we generate. In 2020, the world generated over two billion tonnes of solid waste annually, a figure that, by 2050, will reach 3.4 billion tonnes.1 In low-income countries, 90% of all waste is openly dumped or burned.2 The landfills in these areas then facilitate the transmission of diseases, mainly affecting poorer communities. Waste also impacts natural systems. In 2016, 242 million tonnes of plastic waste–equivalent to about 24 trillion plastic bottles–was dumped, a significant portion of which inevitably ended up in the world’s oceans. In the same year, the equivalent of 1.6 billion tonnes of carbon dioxide greenhouse gas emissions were generated from waste treatment and disposal, accounting for about five percent of global emissions. By 2050, this figure is likely to increase to 2.6 billion tonnes. The problem of excessive waste can be attributed to the linear economy. Raw materials are collected, transformed into products that are used, and eventually discarded. Often, this is not so much a question of needs as it is of wants, wherein the underlying goal is to boost economic growth by producing and selling as many products as possible.3 There is ample evidence that the construction sector is a major generator of waste. This is due to the excessive and inefficient use of resources over the lifetime of a building, the day-to-day behaviours of its occupants, and how its systems are designed and operated. Often it comes down to the question of how long buildings are kept in use. In Singapore, where demolition waste is substantially recycled, there is little interest in stretching the life of buildings, resulting in a tear-down-and-rebuild mindset amongst building owners and developers. The alternative to a linear economy is the circular economy. Advocates for circularity argue that we must:

1 — Eliminate waste and pollution from processes. 2 — Keep products and materials in use for as long as possible 3 — Regenerate natural systems.4 All three have implications for the design of buildings and cities. This book examines how these principles affect decisions during the planning stages. A key finding is that circularity compels a rethinking of the connectivity of people and resource flows, leading to the creation of new networks and pathways. This imperative to connect affects the order in which elements are arranged or assembled, how they are clustered or juxtaposed or stacked, how edges facilitate or impede flow and what new permutations of programmes are needed. The overarching goal is to arrange the parts so that the whole, with new built-in connectivities, operates with a leaner metabolism. The circular city is, therefore, an immensely complex, multivariate and multiscalar undertaking. It requires an in-depth understanding of systems – which systems matter, how they are sized, how they talk to each other. It calls for blue-sky thinking, which is far more intuitive but no less important. The proposals in this book ought to be seen as a delineation of systems, which is universal to any project anywhere, and a subjective position on ‘what-could-be’, which is specific to the context of Singapore. The integration of techno-economic hardware with a software of values, aspirations, and behaviours is key. To unpack these ideas and their implications on urban form, the book is organised into three parts. The first outlines the larger canvas: the global call for circularity in the built environment, a policy initiative in the city-state of Singapore, and an overview of the city's industrial estates. The second explores circularity in the context of an actual site in Singapore: the Sungei Kadut industrial estate. The outcomes of this design exercise are shown as a series of visual collages. The third consists of expert views on circularity, relying in part on the Sungei Kadut study. The drivers and assumptions that led to the masterplan are also discussed, and it becomes clear how visible form is really a set of networks and pathways that enable sometimes invisible biotic and abiotic flows.