Public PhD defence of Nathalie Verbrugghe on "Sustainable Integration of Urban Fog Collectors in Dryland Built Environments through a Multi-scale Biomimetic Approach"

In some of the world’s driest urban regions, where freshwater sources are under increasing pressure and conventional infrastructures are unable to meet rising demands, fog presents a promising alternative. As an atmospheric water resource, fog has received little attention in the context of urban water planning, despite its potential to complement existing systems as a decentralised source. Under climate change, rapid urbanisation, and growing pressures on water provision, fog harvesting emerges as a promising, sustainable, climate-responsive strategy to enhance water resilience in built-up drylands.

Fog consists of tiny droplets suspended in the air, which can be captured passively when advected by the wind and are intercepted by a mesh suspended vertically. This thesis develops a multidisciplinary methodology to explore how fog can be integrated as an alternative urban water source in drylands. It combines research by design, experimental interception mesh testing, and spatial analysis across three scales.

An in-depth literature review and atlas establish the global and historical context of fog harvesting, including existing projects and its relation to biomimicry, map fog-prone drylands and identify design parameters for urban fog collectors (UFCs). The parameters are then applied through a conceptual elaboration of UFCs. Modular Fog Collectors (MFCs) and Rooftop Fog Collectors (RFCs) are explored through conceptual designs while Fog Collector Parks (FCPs) are proposed as strategies for metropolitan fringes.

Laboratory and field experiments optimise fog meshes inspired by biomimicry, testing hybrid Raschel mesh and nylon configurations under controlled and natural conditions in Chile. Results inform the selection of adaptable, low-cost materials suited to varying wind regimes.