FLOOD RISK THROUGH A NETWORK LENS: INTEGRATING ROAD-NETWORK PROPERTIES IN VULNERABILITY ASSESSMENTS

Floods are the primary trigger of some of the most frequent and costly disasters in urban areas, with effects exacerbated by climate change, unsustainable urbanization, and socio-economic inequalities. The European Union’s Floods Directive (2007/60/EC) mandates the creation of Flood Hazard and Risk Maps to assess and manage flood risks. However, these maps often overlook territorial and infrastructural imbalances, limiting their effectiveness for planning purposes. This paper proposes a configuration-informed flood risk index that integrates exposure factors derived from road-network properties. By combining flood hazard data, road physical vulnerability, and road-network exposure indicators obtained through network analysis, the index aims to provide a more comprehensive understanding of urban flood risk and to serve as a valuable tool for emergency management. Exposure accounts for three road network properties: relative accessibility (Integration), preferential routes (Choice), and redundancy (Kemeny-Based Centrality). This approach assigns flood risk values to individual road segments, highlighting the role of the urban grid in supporting both emergency response and recovery operations. The index’s potential to provide actionable insights for planning is demonstrated through its application to the Tuscany region.