Characteristics of salinity in the semi-enclosed Saro Estuary, Takalar, Indonesia

Abstract

Narrowing in the semi-enclosed estuary due to sediment deposits can disrupt shipping lanes and flooding in the upstream area. Because of water circulation in the estuary, both the flow of freshwater from rivers and saltwater from the sea is obstructed. When contaminants originating from Watersheds flow into bays, they can accumulate and continue to degrade water quality. The purpose of this study was to describe the salinity distribution of the semi-closed river estuaries to the high and low tidal conditions. This research is field research at the Saro river, Takalar, Indonesia. The results show that there is a narrowing at the mouth of Saro estuary due to the presence of barrier berm across the estuary and shallow channels due to sedimentation so that seawater is trapped in the back-barrier region at during the tide. Water salinity in the Saro estuary's back-barrier area occurs up to point SL 6 or 0.67 km from the estuary to the upstream of the river. Distribution of salinity in the Saro estuary's back-barrier region can be classified as strongly stratified to well-mixed. At the SL 6 sample point, the salinity values ranged from 30-34.7 ppt, which means seawater, even though the conditions are at the lowest tide.