Simulating blue and green infrastructure tools via SWMM in order to prevent flood hazard in an urban area

Flood risk has become the most important problem in urban areas. A pilot study was carried out in the Güzeltepe neighborhood of İzmir Province, located in the west of Turkey, which is an urban regeneration area with poor socio-economic status and insufficient infrastructure services. According to this study, the areas where water collects and the areas where the slope and elevation are low were determined and the rainwater infrastructure system was integrated into the area. Then, the “Low Impact Development” model, which is an effective method for preventing runoff and water pollution, was examined and applied throughout the area. In this context, 8 scenarios were determined according to the characteristics of the area through the mathematical method SWMM 5.2 program and it was determined how much flooding was prevented by which Low Impact Design (LID) tool. According to the study, the runoff rate is significantly high in the absence of LID systems. Without LID interventions, 70% of rainwater is converted to surface runoff. However, the implementation of various LID systems effectively reduces this rate: permeable surfaces decrease runoff by 13%, infiltration trenches by 30%, bio-retention cells by 29%, vegetative swales by 33%, green roofs by 19%, rain gardens by 30%, and rain barrels by 19%. The development of a method to prevent a risky disaster such as flooding by using blue and green infrastructure within the scope of adaptation to climate change in urban regeneration areas with inadequate infrastructure makes this study valuable. The study of integrating blue and green infrastructure systems into the regeneration strategies of unplanned areas in the city makes this study unique. For this reason, the study focuses on the application technique of blue and green infrastructure systems.