Flood risk assessment of Tatlıçay Basin with GIS and remote sensing

Within the scope of this thesis, characteristic maps and morphometric measurements of Tatlıçay Creek were made using Arcq-GIS program. Digital terrain models used in measurements in Arc-GIS were obtained from USGS programs. The terrain model created for flood analysis was created in OPEN TOPOGRAPHY program and this model was transferred to HEC-RAS program where hydraulic analyses will be performed. Within the scope of this study, Tatlıçay Creek was analyzed in two different ways in HEC-RAS program as 1D and combined one and two dimensional (1D-2D) model. Flood flow rates in different recurrence periods were calculated and obtained by DSI. Thus, different flow rates were determined as Q25, Q50, Q100 and Q500. Q25, Q50, Q100 and Q500 discharges captured for HEC-RAS 1D fixed discharge were obtained by taking the maximum values obtained for each recurrence year from hydrological studies. Accordingly, a study was carried out for four different flow rates: Q25=130.11 m3/s, Q50=165.62 m3/s, Q100 = 209.49 m3/s, Q500 = 290.73 m3/s. Different scenarios were obtained depending on the flow rates in the HEC-RAS program. Different scenarios were obtained depending on the flow rates in the HEC-RAS program. The flood areas for different flow rates are estimated to be 418,918.31 m², 463,787.77 m², 515,591.56 m² and 593,909.37 m², respectively.