Identification of Land Use Affected by Tidal Floods using Unmanned Aerial Vehicles in Coastal Medan City, North Sumatra, Indonesia

¹ Doctoral Program in Regional Planning, Postgraduate School, Universitas Sumatera Utara
² Faculty of Forestry, Universitas Sumatera Utara

^* Corresponding author: a.siddik@usu.ac.id

Abstract

The utilisation of Unmanned Aerial Vehicle (UAV) technology in disaster management has several advantages, including high flexibility and the ability to map disaster-affected areas. The existence of UAV technology can facilitate the mapping of land use in areas affected by tidal floods in coastal areas, Medan City. This research aims to identify land use using UAVs and map areas affected by tidal floods in Coastal Medan City, North Sumatra. The research location is the coastal area in the Medan Belawan sub-district of Medan City. The method used for land use classification is Object-Based Image Analysis (OBIA) from UAV images, with a flying height of 120 m and 80% overlap. The number of field verification points (ground check) was 150 points for accuracy testing using a confusion matrix. The research on creating aerial photo maps with a flying height of 120 meters resulted in a total of 1,304 photos, achieving a Ground Sampling Distance (GSD) spatial resolution of 2.91 cm/pix over an area of 100.60 ha. The results of land use classification using OBIA yielded seven distinct land use classes: settlements, mangroves, open land, developed land, roads, industries, and water bodies. The largest land use area is in the mangrove land use class, with an area of 38.41 ha, and the smallest area is the industrial land use, at 3.76 ha. The results of mapping the potential for tidal flood inundation using OBIA identified a tidal flood inundation area of 11.43 ha, accounting for 11.36% of the total study area. According to the results of the tidal flood simulation modelling, it is evident that land uses with a high potential for tidal flood impact include settlements, open land, developed land, industry, mangroves, and roads. These land uses are vulnerable to tidal flooding, especially near shorelines or rivers. Various parties need to design programs to mitigate the impact of tidal floods in the coastal areas of Medan City, which are expected to intensify with climate change.