Flood risk analysis of strategically important structures to river coasts: case study of wastewater disposal facility

In this research, a study was carried out to determine the risk situations of strategically important facilities such as treatment plants on river banks or residential structures at risk after floods. Within the scope of the study conducted in Turkey, the Konya Bozkır wastewater treatment facility is located by the river, and the river basin where the Aksaray Selime wastewater treatment facility is located was selected as a sample area for the risk analysis study. The ground characteristics of the basin where both wastewater treatment plants are located were determined, and the annual maximum flow rates of the streams were determined from the measurement stations on the streams adjacent to the wastewater treatment plants. By obtaining digital land elevation and location data of wastewater treatment facilities and their neighboring streams, DEM (Digital Elevation Model) files were created, which serve as the basis for the MIKE 21 Flow Model Flexible Mesh program, which is used to determine flood boundaries. Modeling was done in different scenarios with the data transferred to the program, and the program output data of flood boundaries and water height were obtained. Modeling results showed that both facilities remained within the flood boundaries, and flood water surface elevations also changed with the fluctuations in flood flow rates. By evaluating the obtained data, the risks of the Konya Bozkır wastewater treatment plant and the Aksaray Selime wastewater treatment plant in possible floods were examined, and solution suggestions were made to avoid being affected by floods. As a result of the analysis studies, it was determined that water treatment plants located close to rivers in both regions are at risk of being adversely affected by possible floods and that it is inevitable for the facilities to be damaged as a result of floods, especially under the effect of a 200-year recurrence period flood flow. This study has revealed the importance and necessity of conducting such hydrodynamic numerical analysis studies to determine the flood risk for living spaces and strategically important facilities located close to rivers.