Investigating Impact of Sea Sand Mining in Tunda Island Waters, Indonesia Based in Mike 21 Modelling

Abstract

Abstract In Indonesia, sea sand mining was introduced in the late 1970s, and one of the sites is Banten Province, Indonesia. Sea sand mining in Banten waters began in 2003 after the issuance of a permit by the Regent of Serang Regency, namely Decree No. 540/Kep.68/Huk/2003, which was updated by the Regional Regulation of Serang Regency No. 2 of 2013 on the Zoning Plan for Coastal and Small Island Areas in Serang Regency for 2013-2033. Studies related to marine sand mining in Banten, Indonesia are required in accordance with the principle of ecosystem sustainability. The objective of this study is to analyze the impact of sea sand mining on the ecological quality of coral reefs and hydro-oceanographic hue on Tunda Island. The survey method was used to determine the coral reef cover, while the hydrodynamic aspects were carried out by simulating bathymetric data, tidal and wave patterns. In addition, a simulation of sediment distribution was performed to determine the effects of sea sand mining using MIKE 12 sand transport module. The percentage of coral cover in the west, east and south of Tunda Island was 66.00%, 39.67% and 28.15%, respectively. The maximum sea depth around the study site reached 70 m, while it is relatively shallow in the mining area. In the last 14 years, the prevailing wave height ranged from 0.5-0.75 m or 49.02%, and 0.25-0.50 m or 36.69%. In addition, the concentration of TSS was relatively high, ranging from 40 mg/l to 60 mg/l. From the results, the most commonly observed impact of sea sand mining off Tunda Island was the high concentration of TSS. This can be prevented by rotating TSHD vessels, especially in the areas adjacent to Tunda Island.