ANALISIS KAPASITAS PENGALIRAN DENGAN SIMULASI BANJIR KALI SUNTER CIPINANG MELAYU, JAKARTA TIMUR

Abstrak

This study intended to analyze the drainage capacity of Sunter with the help of HEC-RAS program software for the flood simulation. The flood discharge plan using the Nakayasu Synthesized Hydrograph (HSS Nakayasu) method with a 5-year repeat period shows the value of  144.49 m3/s, 10-year period of 169.20 m3/s, 20-year period of 191.48 m3/s, while the 25 year period result is 203.69 m3 /s, and a 50 year period result is 231.40 m3 /s. After knowing the flood discharge plan, the simulation next was done using HEC-RAS simulation with 28 section of STR 82-109 and the result of runoff with five years return period will be achieved. The result of the analysis is done using 28 parts of the river cross section using existing data, meanwhile the whole section can not accommodate the flood discharge plan with a runoff height of 0,74-3.19 m based on the period of 5 years. The difference is 1.23-2.55 m by using the cut and fill method, so that the cross-sectional capacity can resist the waterflow until the 50 years of continuous period.