Authors : Amrullah Mansida, Arsyuni Ali Mustari and Mahmuddin
Abstract: Mamasa watershed as a water reservoir of Bakaru Dam has experienced a highly critical damage due to the dramatical increase in sediment rate annualy. Based on original analysis (New-Jec), the sediment rate in average was 133,000 m3/years and the capasity of dam sediment was 6,919.900 m3 (planning for 50 years). Based on analysis result from PT. PLN Persero Team and Hasanuddin Univeristy, however the sediment rate in average was 423.800 m3/years while the capasity of dam sediment was 6,331.400 m3. It remained 588.500 m3 (±15 years) of dam capasity. The rapid declining brought the energy crisis of PLTA which produces +126 MW of electrical power in South Sulawesi Province. This research used descriptive explorative method which consists of three steps: preparation, field survey and testing sample, analysis of sediment rate using inflow-outflow method and silting of reservoir model restoration. As a result, it showed a incline in signifinal every years, note data ±589,197.00 m3/years. Over the recent 11 yearss, the dam capacity was about 6,481.167.00 m3 and remained approximately 438,732.00 m3 reserved capacity (26 years). Because of this issue, taking real actions is extremely required to prevent or minimze the sediment rate that causes dam silting. There were two proposed methods non-structural method by restoring forests and agricultural lands and stuctural method by restoring sediment in the reservoir with the flushing channel model testing.
Amrullah Mansida, Arsyuni Ali Mustari and Mahmuddin , 2017. Study of Shallowing with Inflow-Outflow Method for the Restoration Model of the Bakaru Dam. Journal of Engineering and Applied Sciences, 12: 4778-4781.