2-dimensional flood analysis due to river mouth sediment movement; Sakarya river Karasu example

Flood natural disaster causes loss of life and property in the world and in our country. Flood disaster is a natural disaster that is predictable and its damage can be reduced. Due to the activities of the quarries on the Sakarya river, it can be seen that the amount of sediment carried by the river has increased and the damage to the surrounding of the river can be seen with satellite photographs.In addition, it is observed that the mouth of the river is closed in time, as described, and there is sediment. It will increase the open class of the river mouth, the age of a possible flood.For this purpose, it is aimed to prepare 5, 10, 25, 50, 100 and 500-year recurrent hazard maps of the Karasu river, which is the downstream part of the Sakarya River and located in the Karasu district. Deterministic and statistical methods were used by using precipitation data for the recurrent flood flow calculation. Using Geographic Information Systems (GIS) programs, the triangular surface model (TIN) and the digital elevation model (DEM) of the region were calculated. The obtained DEM data was transferred to the HEC-RAS program and a two-dimensional hydraulic model was established on the created surface. As a result of the model, the water depth and velocity maps were transferred back to the GIS environment and flood hazard maps were prepared. With the local data obtained from local institutions, the effect of the flood on the Karasu district was examined on the basis of the affected building and the affected area (ha).