Incorporating geomorphological analyses to identify potential criticalities for flood susceptibility in Romagna Plain

Emilia-Romagna, Italy, suffered significant floods in May 2023 consequently, of torrential rains following a protracted drought. Levees, major flood defense infrastructure, were damaged yet played an important role throughout the event, illustrating the critical necessity for effective flood risk management techniques and emphasizing the essentials of comprehensive flood susceptibility assessment in the area. While flood susceptibility mapping takes into account a variety of factors such as land use, rainfall, and hydrological variables, the role of geomorphological features is yet underexplored. This thesis seeks to address this gap by incorporating geomorphological analyses into flood susceptibility assessments, by systematically defining geomorphological indicators and their relationship to flood processes. The methodology involves a multi-step approach, including the synthesis of data analysis, GIS integration, and the development of potential indicators for flood susceptibility, particularly for the Sillaro and Senio Rivers in the region. Historical topographic maps, Geomorphological maps, Digital Terrain Models and several other data were acquired from the online sources and regional authorities of Emilia Romagna. Using Geographic Information System (GIS), this work aims to leverage historical and geomorphological data to pinpoint areas susceptible to future flooding, by analyzing river channel shifts, sinuosity patterns, meander migration, potential cutoff locations and post-event criticalities. The insights of this study reveal a strong link between historical geomorphological evidences, current sinuosity patterns, and flood susceptibility. The identified critical locations from the post-event orthophoto aligns with the area highlighted in the geomorphological analyses, suggesting significant correlation of geomorphological aspects to flood susceptibility, especially for the Senio River. The patterns of riverbank expansion and contraction further emphasizes the dynamic nature of the river system in the plain. These insights underscore the essentials of incorporating geomorphological analyses into flood susceptibility mapping to enhance flood risk management in the region.