Application Of Hec-Ras And Arcgis For Flood Mapping Surfaces In Urban Areas - Case Of The City Of Gostivar

Abstract

Floods are natural disasters and often result in great material loss and even loss of human life. Their early prediction is necessary to provide protection from their harmful effects. In order to create accurate, realistic solutions, there is a need for concrete determination of the flood areas. In recent decades, various modern techniques have been used to map possible flood areas. One of them is the HEC-RAS software package. The purpose of this paper is to map the flooded areas on part of the river Vardar in the city of Gostivar and to give the competent authorities a base for real solutions for flood protection in urban areas. Using the software package HEC-RAS in combination with ARC-GIS, a 1D model was made, which obtained the large waters, namely Q20% = 22 m3/s, Q10% = 39 m3/s, Q4% = 68 m3/s, Q2% = 95 m3/s and Q1%= 124 m3/s. The output data are displayed on the Orthophoto map. Then, using ArcGIS, the boundaries of the floodplains are displayed on Google Earth. It was concluded that the HEC-RAS software package in combination with ARC-GIS is a useful tool, capable of mapping critical areas, which would serve as the basis on which various possible flood protection solutions can be provided in urban areas.