Determination of the Flood Risk Map: Case Study-Kirazlı Creek (Trabzon-Vakfıkebir)

Abstract

In this study, population analysis has been carried out in buildings in order to determine the riskiest situation in line with the flood hazard and depth maps obtained by using Q500 flow rate, with 1 and 2 dimensional hydrodynamic models installed with Hydrologic Engineering Center-River Analysis System (HEC-RAS) software for Kirazlı Stream in Trabzon Province, Vakfıkebir District, which was selected as the project area. The reason for choosing the study area in the Eastern Black Sea Region is that it receives excessive meteorological rainfall and has a flood risk in terms of topography. In line with the previously prepared flood hazard and depth maps; with the aim of estimating the number of people affected by the flood, socio-economic activities and possible economic damages, the risk status of the buildings that may be affected by the flood was tried to be determined. While determining the flood risk situation, the economic damage was calculated according to the type of the buildings, after determining the houses, factories, greenhouse areas, locations and the number of populations living in that region, on the flood depth map with the Geographic Information System (Arc-GIS) program. The flood unit loss is calculated by dividing the total economic loss value of the buildings by their own areas, and the maximum and minimum loss values per unit square meter of these calculated values are normalized between 0 and 1. In the population risk situation, using the same method, the population was collected with the normalized unit flood damage and the flood risk situation was determined. In this study, in which the flood risk percentages were determined, according to the condition of the buildings affected by the flood, the standard deviation analysis made by the acceptance method determined the hazard risk degrees. As a result of the study carried out in this context, it is thought that it will be beneficial to rebuild or improve the existing art structures with the necessary flood control structures in certain parts of the stream and to clean the bed regularly once a year to minimize the effects of flood damages. © 2021, Ankara University. All rights reserved.