Determining the effect of changes on flood risk in flood basins having no gauegd stations; case study Rize, Guneysu

Since flood events occur under the influence of time varying state/driving variables, they cannot be determined precisely in advance. In this respect, the use of probabilistic approaches is of great importance in flood studies. Furthermore, deterministic approaches in which mathematical models are used to represent flood events by examining the physical aspects of hydrological events need to be adopted. The first step for flood modeling studies where deterministic and probabilistic approaches are used is to make measurements to obtain the necessary natural data. To do so, it is necessary to establish a measurement network in a sufficient size and precision. It is not possible to accurately model the flood event and to produce flood hazard and flood risk maps without generating data from gauged stations. However, flood hazard and risk maps need to be produced for effective and sustainable flood risk management. It is very difficult to model the flood event and identify the elements at risk particularly in mountain rivers with high slope and flow rate, flowing along narrow and deep valleys with steep slopes. The lack of gauged stations in such rivers, the multiplicity of unknown variables and the complexity of the relationships between them make it more difficult to generate flood risk maps In this dissertation, a flood modeling study was carried out for the Güneysu Stream, which does not have the gauged station at the upstream part. In addition, the importance of land use change in flood risk map generation was exhibited and the temporal variation of flood risk change was analyzed. Regional non-physical recommendations for Sustainable Flood Management were presented. In this study, flood modelling, hydrograph simulation, demographic information, Remote Sensing techniques and Geographical Information Systems were used.