A Building Information Modelling (BIM) And Geographical Information Systems (GIS) Integrated Framework for Flood Risk Assessment (FRA) of Future Built Scenarios

Abstract

The contemporary era is marked by the unprecedented challenges posed by climate change to both existing and future urban developments. Addressing these challenges is imperative to circumvent potential loss of life and property damage stemming from urban flooding incidents. Prevalent Flood Risk Assessment (FRA) methodologies are inadequate in evaluating future built scenarios against flood risks. The prospect of integrating Building Information Modelling (BIM) and GIS for pre-emptive assessment and mitigation of flood risks for yet-to-be-built urban developments offers a promising solution. Contemporary techniques in Remote Sending (RS) and GIS allow simulation of existing conditions at varying levels of detail. BIM allows data rich and visually realistic modelling of existing and future built assets. When utilized in integration BIM and GIS enable us to achieve a digital twin model of future built scenarios, that is visually realistic and rich in semantic data. The proposed framework involves the integration of BIM models of built assets within varying resolution terrain data, enveloped within a BIM-GIS integrated digital twin of the projected built environment. This enables FRA at varying hierarchical levels, yielding insights that contribute to flood resilient design and effective mitigation strategies. The adoption of BIM-GIS compatible Common Data Environments (CDE) fosters stakeholder collaboration, bolstering design revisions, flood mitigation planning and management. The framework is demonstrated on a yet to be built, planned housing society in zone V, Islamabad, Pakistan. The housing society has been modelled using available BIM and GIS toolkits and analyzed for risks posed by a potential 100-year return period flood. The results show that the framework yields visually realistic outputs, that boost stakeholder understanding and effectively identifies design shortcomings. It also facilitates design and analysis of mitigation proposals / interventions that reduce flood risks and improve flood resilience of future urban development.