THE INFLUENCE OF THE JAKARTA BAY RECLAMATION ON THE SURROUNDING TIDAL ELEVATION AND TIDAL CURRENT

Abstract

The Jakarta Bay artificial island reclamation is a part of the spatial arrangement of the Province
of DKI Jakarta which is stated in Governor Regulation No. 121/2012. The regulation divides the area into three
sub-regions, west, middle and east. In the middle sub-region, the influence of the reclamation of artificial
islands, named I, J, K, L and M islands, on the tidal elevation and tidal current is investigated using
hydrodynamic modeling with inputs of the river discharges coming into the bay. The plan to build a gate at the
southern side of L island is also a part of the study. For normal river discharge, the existence of the reclaimed
islands does not influence the tidal elevation significantly, whereas the tidal current is affected by a 200%
intensification at a few points. For flood river discharge with a 25-year return period, the tidal elevation is more
unstable, with the maximum rising or falling by 2 cm at most locations. The current phase shift is found, and
along with the current intensification of round 200%, there is a reduction of the current magnitude. The
reclamation and the gate cause some tidal changes, although these are still within the normal range that can
accommodate daily activities. The reclamation scenario with the gate is better for the channel at the eastern
side of L island since it results in a lower tidal elevation.
Keywords: Numerical modeling, Coastal environment, Tidal elevation, Tidal current, Jakarta Bay
reclamation.