Winda Harsanti, Yuni Rahayu, Ratih Indri Hapsari, Agus Suhardono, Medi Efendi, Moh. Charits
Kali Bogel is a river with a length of 8.76 km, located in Sutojayan Sub District, Blitar. This river has a yearly flood problem that is caused by sedimentation, river cliff erosion, and also deforestation. To solve this problem, channel normalization can be done by increasing the width of the old channel to 10 m. This new channel was planned using gabions with square shape. HEC-RAS modelling was used to control whether the river was adequate or not to accommodate the flood discharge for 25 years of return period, which was calculated using Nakayasu Synthetic Unit Hydrograph. The result of maximum flood discharge is 40.263 m3/s. Using unsteady flow for HEC-RAS modelling, the result shows that gabion channel is adequate to flow the maximum discharge. Another control for this normalization is velocity, which is maximum velocity happening on Station 26 reaching 6.7 m/s. On this station, 190 mm for the diameter of stone and 0.5 m of the wall thickness are applied. © 2023 Author(s).
Politeknik Negeri Malang, Jl. Soekarno Hatta No. 9, Malang, 65141, Indonesia