Pemanfaatan Data Penginderaan Jauh untuk Analisis Perubahan Lahan dan Curah Hujan terhadap Aliran Permukaan di DAS Ciliwung

Abstract

The potential of flood occurrence in Jakarta has increased year by year. It caused by the presence of positive growth population that led the landuse change in the watershed (DAS) of Ciliwung. This landuse change has raised surface runoff in Jakarta and surrounding areas. This study aims to analyze the effect of landuse changes and precipitations to the surface runoff in Ciliwung watershed using Soil Conservation Services (SCS) method based on remote sensing satellite data. The results showed that the heavy rainfall has triggered the high runoff in the certain area. This heavy rainfall had various distributions in each sub-watershed so it was difficult to find runoff pattern in the watershed. Based on the soil hydrologic group (KHT), the forest area in upstream which has C type had lowest runoff coefficient (C) value than D type. The settlement and agricultural area in the central and downstream watershed had the highest C value. The decreasing of forest area in the upstream watershed was found around 1.7 % along with the increasing of settlement area and mix garden/plantation area in the central and downstream watershed that were 17.7 % and 10.4 %, respectively. Those conditions have caused the increasing of runoff coefficient around 24 % from year 2002 to 2012. The influence of ENSO phenomenon such as La Nina has caused high surface runoff in the Ciliwung watershed causing inundation/flooding in the downstream watershed area (Jakarta and surrounding areas) in those years.