Extending the Fresnel Platform with a 3D Isometric Graphical Interface for Land-Use Scenario Design in Hydrological Modeling

Urban areas are increasingly exposed to localized extreme rainfall events, with evidence suggesting a trend toward higher precipitation volumes and more frequent short-duration, high-intensity storms, posing major challenges to infrastructure resilience and public safety. 

Urban hydrometeorology is characterized by highly nonlinear processes, strong interactions with geophysical systems, and pronounced variability across spatial and temporal scales, making both scientific understanding and operational management particularly demanding. 

Within this context, the Fresnel platform is a state-of-the-art urban hydrometeorological observatory combining conceptual modeling approaches with extensive field measurements. One of its components, RadX, is a Software-as-a-Service (SaaS) platform that provides real-time and historical data from high-resolution sensors, together with a graphical user interface (GUI) for Multi-Hydro, a fully distributed and physically based hydrological model developed at École nationale des ponts et chaussées (ENPC). Multi-Hydro relies on four open-source software components representing different processes of the urban water cycle. The RadX GUI allows users to efficiently run simulations using dedicated high-performance computing resources, configure multiple scenarios for a given catchment, modify land-use parameters, and assess their impacts on drainage system discharges. 

The originality of this contribution lies in the development of a new 3D isometric graphical interface based on an open-source game engine. Unlike conventional interfaces relying on the editing of raster matrices, this approach provides a more intuitive and spatially explicit visualization of land-use configurations. It enables a clearer representation and manipulation of Nature-based Solutions (NbS), such as porous pavements, whose implementation often remains abstract when expressed solely through raster data. 

Beyond hydrological modeling, RadX also supports integrating shared value principles into business models to enhance resilience and sustainability. Within the PIA3 TIGA-CFHF project (“Construire au futur, habiter le futur”), it promotes an integrated vision where economic activities are situated within a complex socio-environmental system, aligning economic performance with environmental and societal objectives. 

To support this transition, RadX aims to incorporates multifractal and advanced socio-economic analysis tools that enable organizations to assess performance and develop shared value–oriented strategies aligned with measurable environmental objectives. 

The RadX platform is continuously improved through an iterative development process driven by feedback from students, academic researchers, and industry practitioners, and may integrate additional visualization or forecasting components in future developments.