Paola Piras – Materiality and governance of the ultra-high-speed sociotechnical system in Dakar (Senegal): strategic vision for digital infrastructure, metropolitan planning, and construction projects

This thesis analyzes the development of a very high-speed sociotechnical system (fiber optic network and data centers) and the urban transformations of a West African metropolis by examining the conditions and modalities of "digital urbanism" in Dakar (Senegal). The aim is to understand how digital infrastructure and urban spaces shape each other and to propose an interpretation based on materiality rather than overlooking inert materiality. Drawing on work from urban studies and social approaches to technology inspired by Science and Technology Studies (STS), the study focuses on the sociopolitical, sociotechnical, and territorial dimensions of the deployment of very high-speed broadband infrastructure, which it analyzes on three scales, corresponding to distinct spheres of action and temporalities, and in different types of intra-urban spaces. Using qualitative methodology (interviews, participant observation, mapping), the thesis demonstrates the ambivalent relationship between the privatized development of the ultra-high-speed socio-technical system and socio-spatial inequalities. At the national and metropolitan levels, it highlights the links between urban planning actors and powerful international telecommunications operators, as well as their respective influence on metropolitan digital development in a context marked by neoliberal policies. At the street level, it analyzes the role of network engineers and technicians, highlighting, through a study of construction sites and work "in situ," the role of material contingencies, informality, and sociotechnical "tinkering," but also that of "street" technical expertise, which is essential to the material development of ultra-high-speed infrastructure. The analysis of the governance of deployment, coupled with that of urban materiality and metropolitan socio-spatial developments, has made it possible to characterize a digital urbanism that differs according to urban profiles. However, while emphasizing the decisive influence of telecommunications operators and the insufficient capacity of public authorities to prescribe and regulate, the thesis identifies self-regulatory mechanisms that are sometimes beneficial to the general interest and mechanisms for partial catch-up in certain less "attractive" neighborhoods. These results lead to a nuanced view of the effects of the "privatization" of digital development on urban fragmentation and suggest areas for reflection for the public re-engagement of digital urban planning thinking and practice in Dakar.