STUDI TRANSPOR SEDIMEN DI TELUK BENOA MENGGUNAKAN PEMODELAN NUMERIK

Benoa Bay is a semi-enclosed estuary located in the south of Bali. This area is became estuary for several rivers in Bali. The river is a source of material such as sediment transport stream that flowed into the sea. Sediment transport processes in Benoa Bay can be approximated by numerical modeling FVCOM (Finite Volume Coastal Ocean Model) to determine the distribution of sediments found in the bay area. Research carried out at Benoa Bay area in January 2016. The results of numerical models show that the process of sediment movement will follow the current pattern shape. The pattern of the movement of currents in the Benoa Bay will follow the pattern of tide where the current will flow lead into the bay at high tide and vice versa. Average flow velocity at the mouth reaches 0.8 m/s at the time to the tide and 0.9 m / s at the time towards low tide. Current speed will slow down when the condition of the highest and lowest tide that is only reached an average of about 0.3 m/s. The highest sediment concentrations occur in the section near the mouth of the river that reached 100 mg/L and the mouth of the bay, which reached 150 mg/L. The high concentration of sediment at the mouth of the bay due to the erosion of the bottom waters due to the flow velocity is high. The results of the validation by tidal elevation models obtained root mean square error (RMSE) of 9:18 cm with a coefficient of determination (R2) reached 0.97. For the comparison of model results with observational data in the form of sediment Total Suspended Solid has a level of correlation of 0.77. Keywords: Benoa Bay, Sediment, Numerical modelling