Using HEC-RAS for analysis of flood characteristic in Ciliwung River, Indonesia

Jakarta is a large city with a population of around 10 million who still suffer flooding during the rainy season. A program that is being implemented to reduce flooding that occurs every year is called "Total Solution for Ciliwung". One of the programs is to build 3 (three) diversion channels on the Ciliwung River located in Kalibata, Kebon Baru, and Kampung Melayu respectively. This paper only discusses the problem of flooding in Jakarta in the aspect of hydraulics. This research was conducted with the aim of analyzing the character of floods in the Ciliwung River based on variations in the choice of diversion channel locations. Analysis of flood characteristics using the HEC-RAS 4.1 Program. The results of the analysis provide conclusions, that variation 7 (seven) provides the most optimal reduction in flooding. The main result is, the water level profile in point 260, the water flow is sub-critical which the water level at +18.50 m or decreases by 0.5 m from the existing condition at +19.00 m. While the inundation area become of 2,414 km² is reduced by 0.60 km² or by 20% from the existing condition 3,018 km².