# GIS-Based Flood Assessment Using Hydraulic Modeling and Open Source Data: An Example of Application
## 4 Discussion
### The Role of Hydraulic Modeling in Flood Risk Assessment and Management  
Hydraulic modeling using specialized software enables the simulation of hydraulic conditions for various scenarios. These simulations are useful for water resource management, flood risk assessment, hydraulic structure design, and environmental protection [85; 86].  
Studies in the specialized literature and the current study have demonstrated that the HEC-RAS program is a valuable tool for hydraulic analysis, hydrology simulation, flood forecasting, and management [87; 88].  
Forecasting the magnitude of hydrological and hydrogeological risk phenomena is essential for addressing economic, environmental, and social challenges and remains a fundamental challenge for hydrologists and specialists in related fields [89].  
In this study, processed and field-validated DEM data demonstrated high accuracy, confirming their suitability for hydraulic modeling in HEC-RAS. The integration of LiDAR data enabled a precise representation of river geometry, which is essential for reliable hydraulic simulations.  
The analysis of cross-sections and hydraulic modeling results highlighted significant variability between river segments, influencing transport capacity and the potential expansion of floodable areas, with an increased risk of severe flooding in narrower and shallower zones, particularly in scenario S4 (60 m\({}^{3}\)/s).  
Parameters such as water velocity or flow cross-sectional area provide valuable insights into river behavior under different conditions. For example, an increase in water velocity along the thalweg and the flow area underscores the risks associated with erosion and transport capacity.  
An additional factor that could significantly influence these results is sediment transport, which plays a crucial role in modifying cross-sections and the natural evolution of riverbeds [90]. Studies show that excessive sediment accumulation can contribute to riverbed clogging, reducing water transport capacity and amplifying flood risk, while excessive erosion can affect bank stability and local infrastructure. Although this study did not include a detailed analysis of sediment transport, integrating such a component could increase the complexity of hydraulic modeling and provide a more detailed understanding of river dynamics in high-flow scenarios. In future research, evaluating the interaction between water flow, sediment deposition, and erosion could contribute to a better understanding of hydrological processes and the optimization of flood risk management strategies [90].  
The 3D visualizations and longitudinal profiles offered an in-depth understanding of the river's hydraulic behavior. The representation of floodable areas for each scenario allows for better risk assessment and can guide decision-making in water resource management and infrastructure protection.  
The four defined scenarios (S1-S4) illustrate a clear progression of flood risks. While the low flow in S1 presents minimal risks, scenario S4 highlights an urgent need for preventive measures such as levee reinforcement or the expansion of buffer zones.  
The results obtained are directly applicable to developing land-use plans in flood-prone areas. The study underscores the need for integrated approaches that include both infrastructure measures and ecological strategies for risk mitigation.  
Our study highlights the complexity of the interaction between hydraulic parameters and land use, offering valuable perspectives for water resource management and flood prevention planning.