ANALYSIS OF THE EFFECT OF SEDIMENT TRANSPORT ON THE CAPACITY OF THE BRINGIN RIVER FLOOD IN THE BRINGIN RIVER FLOOD CONTROL BUILDING, SEMARANG CITY

• Main Author: Pondaag, Ricky
• Format: Theses
• Language: Indonesia
• Subjects: Teknik (Rekayasa, enjinering dan kegiatan berkaitan)
• Online Access: https://digilib.itb.ac.id/gdl/view/63273
• Institution: Institut Teknologi Bandung

The Semarang City flood control project carried out on the Bringin River in the form of embankments and river normalization. Normalization is carried out by widening the river segment from 6-12 m to 25-45 m. This flood control building has a risk of being disturbed by sedimentation. One of the causes of this sedimentation is land use changes that occur in the upstream of the Bringin watershed. Sedimentation can reduce the effectiveness of flood embankments, so it is necessary to carry out an analysis that predicts the sedimentation rate in the Bringin River and the effect of this sedimentation on the storage capacity of existing flood control buildings. This study aims to determine the impact of sedimentation on the normalized embankments and sections of the Bringin River. The analysis was carried out using HEC-RAS 6.1.0 software to simulate changes in the riverbed due to sedimentation in the Bringin River. The simulation uses two scenarios, namely using daily discharge data and dominant discharge. The results of the HEC-RAS 6.1.0 simulation in the first scenario show that for 5 years the riverbed has changed with sediment heights ranging from 0.12 to 1.10 m, with a sedimentation volume of 55,387.64 m3 or 11,077.53 m3/year, the effectiveness of the Bringin river embankment has decreased by 24%. while the simulation results for 10 years, the sediment height ranged from 0.44 to 1.39 m, with a sedimentation volume of 103.532.47 m3 or 10.353.25 m3/year, the effectiveness of the Bringin river embankment decreased by 31.83%. In the second scenario using dominant discharge, it shows that for 5 years the riverbed changes with a sediment height of 1.22 m but there is scouring of the riverbed as deep as 0.93 m, with a sedimentation volume of 16,363.11 m3 or 3,272.62 m3/year, for the effectiveness of the Bringin river embankment has decreased by 16.60%. while the simulation results for 10 years the riverbed changed with a sediment height of 1.27 m but there was scouring of the riverbed as deep as 0.48 m, with a sedimentation volume of 40,279.93 m3 or 4,027.99 m3/year, for the effectiveness of the Bringin river embankment decreased by 29.68%