Analisa Tingkat Kerawanan Banjir Daerah Aliran Sungai Deli Provinsi Sumatera Utara

Abstract

This study uses a weighted overlay method by considering several parameters that affect the level of.flood vulnerability in Das Deli, North Sumatra Province. Some of the parameters considered include rainfall, slope and land elevation, soil type, land use, and river density. Each parameter is given a weight and value according to each classification. The overlay process uses ArcGIS 10.8.l sofnvare, which utilizes Remote Sensing and Geographic Information Systems (GIS) to analyze and present geographical data digitally. The results showed that almost all parts of Medan City around the Deli watershed area have a high level of vulnerability to flooding. Slope, topographic wetness index and land use are the main factors causingflooding. Slopes with a range of0-8% in most areas of Medan City are classified as very prone to flood inundation. This is due to the flat topography of the area and the high density of river flow, making the area vulnerable to becoming a water catchment area when it rains and increasing the risk of flooding. For topographic wetness index a value greater than 14 is very vulnerable, and the use of residential land and open land is categorized as very prone to flooding. Some areas, such as the Sei Putih II Village area, Medan Petisah District, have a flood inundation percentage of 41. I 6% of their total area, which is the area with the highest flood inundation percentage. For the area with the largest flood inundation area is Tanjung Rejo Village, Sunggal District with a flood inundation area of 67. 05 Ha. With this flood-prone map, efforts to manage and mitigate floods in Medan City can be carried out. Information on vulnerable locations can be used to take appropriate preventive and countermeasures, such as building adequate drainage, regulating land use, and controlling river flows ..