Utilization of an ArcGIS geographic information system and a HEC-HMS hydrological model to simulate some of the Tafna sub-catchments

This study aims to develop a flood forecasting system for the Tafna watershed in northwestern Algeria. The system will combine Geographic Information Systems (GIS) and the hydrological modeling tool HEC-Geo HMS to simulate the watershed's behavior during extreme rainfall events. By using remote sensing data, the study will improve the accuracy of hydrological parameter estimation and physical process representation. The methodology involves several steps It begins with data collection and Preparation: Extracting SRTM images and creating a digital terrain model (DTM). Next, GIS Analysis: Delineating basin boundaries and extracting physical characteristics like slope, surface area, and the hydrographic network. Finally, Hydrological Modeling: Integrating the collected data into HEC-Geo HMS to simulate the watershed's response to various rainfall scenarios. Based on IDF curves from 1990-2013, a 24-hour, 100-year rainfall event was simulated using the HEC-HMS model. Runoff volume was estimated with the SCS-CN method and transformed into a flood hydrograph using the SCS unit hydrograph method. This analysis allows us to assess the basin's vulnerability to extreme events.