Mukhsan Putra Hatta1, * ,Muhammad Arsyad Thaha1 , , Marthen P Lakatua2 1 Departement Civil Engineering, Hasanuddin University, Makasar, Indonesia 2Departement Civil Engineering, The Mollucan Christian University of Indonesia, Ambon, Indonesia
Abstract,
The sedimentation occurring in the outer Ambon bay as a result of the effluent from Way Ruhu river causes the reduction the mouth of the outer Ambon Bay, so that it influences the current movement pattern and sediment distribution. This research aimed at analyzing the current movement pattern and sediment distribution pattern in the outer Ambon bay using two scenarios: with the reclamation and without reclamation. The research used the numerical model of MIKE 21DHI with modules of the hydrodynamic and mud transport. The research result indicates that the simulation current velocity with the absence of reclamation ranged from 0.0-0.4 m/s, while with the presence of the reclamation, the current velocity is slightly higher that is between 0.0 – 0.6 m/s the various velocity patterns. The sediment distribution pattern in the outer Ambon bay as the result of the effluent from the way Ruhu river follows the current movement. If the conditions leading to the tide and the highest tide, the sediment going out from way Ruhu river is pushed into the bay and vice versa, when the condition leading to the recede and lowest recede, the sediment concentration is pulled out from the bay. The suspended sediment concentration is between 0.002 kg/m3 – 0.030 kg/m3 with the various patterns. The suspended sediment concentration to the condition without reclamation is more collecting if compared with the suspended sediment
1. Introduction
Ambon city has the Gulf consisting of the Bay of Ambon In Ambon Bay and beyond. In this Bay there are also several large and small rivers which boils down to the Bay of Ambon Out include River Way Ruhu. The river has a length of approximately 4.5 km, has a large water areas upstream and downstream at the village of Galala. In the Way many Ruhu deposition of sediment that occurs mainly in the estuary towards the Bay of Ambon. The observations show that the River upstream of the River in a State of stable and water flow of the river is quite clear and invisible existence of sediments that could potentially cause the flow of sediments or signs of avalanche cliff. Sedimentation also resulted in the closure of the estuary mouth of the river where Ruhu way be small thus leading to flooding in the rainy season in the surrounding area [1]. Until now there has been no local government efforts to deal with it seriously.
