Towards a composite service to manage urban metabolism: What urban technical networks and decentralized infrastructure share

Decentralized urban flow management systems, rainwater collection systems and local bio-waste composters seem to offer a distinct process from large technical networks, as they circulate and relocate urban metabolism. This article examines decentralized systems not as alternatives to large technical networks, but as flow management techniques in themselves. The paper is based on the analysis of “chaîne opératoire”: tools developed by the anthropology of techniques that unpack the material steps in their technical processes. This analysis helps to make the specificity of decentralized systems more tangible.The “chaîne opératoire” of bio-waste composting in the Île-de-France region shows that there is no difference in nature between industrial and decentralised systems. They share many characteristics that need to be better understood in order to articulate the two scales: the material analysis of collective home composting shows how institutions contribute to the inefficiency of the system because of the lack of a detailed knowledge of decentralized processes. Furthermore, these results call into question the traditional oppositions in urban services between network and post-network, high-tech and low-tech, and centralized and alternative systems. The theoretical and methodological opening in urban planning to the anthropology of techniques proves fruitful in capturing the multiple techniques of urban metabolism management, both from a material and a social point of view.