Pesanggrahan River Watershed Flood Potential Mapping in South and West Jakarta with LiDAR Data Segmentation

Abstract

Most of large urban areas are historically grown around a river from small communities that eventually merge into present urban area. Area around the river, known as the watershed can be described as flood water catchment basin that hold water overflow from the river during rainy season. This condition is negligible at the beginning when most of these areas are farmlands or undeveloped, but as the area developed further, with more people reside in the area, this increasingly pose significant problem. Declining environmental quality in Jakarta is now the dominant factor of the recent natural disasters. This research is aimed to map the potential of areas around Kali Pesanggrahan in South and West Jakarta by LiDAR data-derived the Digital Elevation Model. The objective of this segmentation is to find the contour lines of the surface model data. Data processing in this research is using LiDAR data, after the digital surface model has been created, the data is then segmented beginning from the river surface to obtain the base area between the riverbanks. Subsequent step is to find the area increase corresponding to the elevation from the riverbank at 1m intervals. The result of this research is the flood potential area information, especially along the Pesanggrahan river in South Jakarta, ranging from the baseline river water level to 1 meters above normal level.