Pemodelan Numerik Pola Arus dan Sebaran Sedimen Tersuspensi di Teluk Benoa Bali

Abstract

Teluk Benoa merupakan kawasan perairan semi tertutup dan termasuk kawasan estuari dangkal yang memiliki ekosistem perairan penting, yaitu ekosistem mangrove, padang lamun, dan terumbu karang. Pembangunan reklamasi di Pelabuhan Benoa dan pembangunan jalan tol di Teluk Benoa diduga telah meningkatkan sedimentasi. Penelitian ini bertujuan memodelkan pola arus dan sebaran sedimen tersuspensi pada Musim Barat dan Musim Timur di perairan Teluk Benoa. Model numerik digunakan untuk menggambarkan proses hidrodinamika sebagai penggerak utama dari proses pergerakan polutan di perairan. Pola arus hasil model di perairan Teluk Benoa memiliki pola yang sama pada Musim Barat dan Musim Timur, yaitu arus menuju Barat Laut memasuki teluk saat air pasang dan berbalik arah menuju Tenggara ke arah luar teluk saat air surut dengan kecepatan arus Musim Barat berkisar antara 0 – 1,6583 m/s dan Musim Timur berkisar antara 0 – 1,4729 m/s. Sebaran sedimen tersuspensi tersebar cukup tinggi pada Musim Barat dibandingkan dengan Musim Timur. Sebaran sedimen tersuspensi Musim Barat berkisar antara 0 – 846 mg/L dan Musim Timur berkisar antara 0 – 598 mg/L.

Benoa Bay is a semi-enclosed water body that includes a shallow estuary area that supports important aquatic ecosystems, including mangrove ecosystems, seagrass beds, and coral reefs. The reclamation of Benoa Harbor and the construction of a toll road in Benoa Bay are suspected to have increased sedimentation. The objective of this study is to model ocean currents and suspended sediment distribution during the Northwest and Southeast Monsoons in the waters of Benoa Bay. Numerical models are used to describe the hydrodynamic process as the main driver of the process of pollutant movement in the waters. The current pattern resulting from the model in the waters of Benoa Bay has the same pattern in the Northwest and Southeast Monsoons, namely the current moving towards the outside of the bay at low tide and the current moving in a reverse direction, entering towards the inside of the bay at high tide, with the current velocity of the Northwest Monsoon ranging from 0 – 1.6583 m/s and the Southeast Monsoon ranging from 0 – 1.4729 m/s. The distribution of suspended sediment in the Northwest Monsoon is quite high compared to the Southeast Monsoon. The distribution of suspended sediment in the Northwest Monsoon ranges from 0 – 846 mg/L and in the Southeast Monsoon, it ranges from 0 – 598 mg/L.