摘要:Based on the Comprehensive Flood Management Plan (CFMP), one of the flood control alternatives in the Ciliwung Watershed is using the dry dam construction. Construction of Ciawi dam and Sukamahi dam who are located in Bogor District, are expected to decrease the flood peak and increasing the time concentration in order to reduce the impact caused by a flood in DKI Jakarta due to Ciliwung River. With the construction of Ciawi dam and Sukamahi dam, it is necessary to conduct a research on the effect of both dams construction in Katulampa Weir, one of monitoring point dams on the DKI Jakarta Flood Early Warning System. Hydrological analysis with Win-TR 20 and HEC-RAS was conducted to identify the changes in the flood level of Flood Early Warning System in DKI Jakarta with and without both dams are available. The results of this study indicate that the peak floods decreased by around 2.5% after the implementation of Ciawi dam and Sukamahi dams. The impacts of this reduction will not affect the Flood Early Warning System level at Katulampa Weir significantly.