Ergene river: Determination of flood flow and hydrodynamic flood analysis between Tekirdağ Muratli - Kırklareli Pehlivanköy

Floods are natural disasters that can reach dangerous levels due to heavy rainfall or snowmelt, causing loss of life and property with economic damages. They have complex solutions where a series of tedious steps come together with countermeasures. Although Ergene River in Thrace Region of Türkiye is the most important resource of the region, due to its plain topography, it has suffered from many flood disasters. In the thesis, the importance of water to human life, the development of water resources management in Türkiye, are given, the Flood and Sediment Control Regulation is discussed and Ergene River with its geography is studied. Normal, Log-Normal, Three Parameter Log-Normal, Gamma, Log-Pearson Type III and Gumbel Distributions were applied to the precipitation data of the stations existing on the route of the river and its main branches in 87 km section of the Ergene River between Muratlı-Pehlivanköy and 2, 5, 10, 25, 50, 100, 200 and 500 year flood recurrence frequencies were calculated. After checking the distributions with Kolmogorov-Smirnov Goodness-of-Fit Test, Log-Pearson Type III Distribution was determined as the most appropriate one. Q500-Q1000 flow rates of the axes and 12 main branches of the Ergene River were determined with Mockus Method, a synthetic method, by the aid of Thiessen Polygons. The digital elevation model was divided into 5 maps and converted into TIN with AutoCAD Civil where its projection was defined with ArcGIS. The elements such as rivers and sections were defined for the route transferred to HEC-Geo-RAS. The Manning roughness coefficient was determined by Cowan Method and 18 bridges were defined on the channels. 2-dimensional modelling and hydrodynamic investigations in the open channel were made with HEC-RAS; flood mapping, velocities in the channel, the state of the bridges, their longitudial profiles were given. According to the obtained results, for the settlements, the construction of a 16,21 km long embankment and a 2,9 km flood channel, the mapping and analysis of Kaynarca Stream including Lüleburgaz, the mapping and analysis one of the small branches; Pancarköy Stream, on the D555 Highway route for transportation, the 10,93 km boulevard for the railway and 2,83 km of protection/upgrade proposals, the bed cleaning of 3 main branches and 25 km of route in Ergene River has been considered. Interpretations on river banks, floors, bridges are mentioned. Suggestions; since it was interpreted separately from economy, profitability, environmental, mechanical and geotechnical situations, the study has become an example only for the planning stage.