Flood modeling of the Ankara river in the Sincan district of Ankara province using HEC-RAS software

In today's world, the effects of climate change, coupled with rapid population growth, unplanned urbanization, improper land use, and interventions in riverbeds, significantly increase the risk of flooding. In Turkey, floods rank second only to earthquakes in terms of causing the greatest loss of life and property. This reality highlights the necessity of analyzing flood risks through scientific methods and taking preventive measures. In this study, the flood risk of a specific section of the Ankara River passing through the Sincan District of Ankara Province has been examined in detail. Within the scope of the research, 1/1000 scale base maps and land use data of the region were obtained. Using AutoCAD Civil 3D software, topographic data of the stream bed and its surroundings were digitized, and cross-sections were created to prepare the necessary data for hydraulic modeling. Subsequently, one-dimensional flood analyses were carried out using Q100 and Q500 flood discharges with the HEC-RAS software. As a result of these analyses, flood inundation maps were generated, and the areas that could be affected by each flood scenario were identified. Based on the analysis results, possible engineering measures to reduce the flood risk around the Ankara River were evaluated, and the potential outcomes of implementing these measures were determined. This study demonstrates that the integration of hydraulic modeling and geographic information systems is an effective method for identifying flood risks and planning appropriate mitigation strategies.