Seawater intrusion analysis in the coastal region of Banda Aceh by using Geographic Information System (GIS)

Abstract

Seawater intrusion is an environmental problem in many coastal regions which can harm the sustainability of groundwater resources in the future. Banda Aceh as the capital city of Aceh Province has a wide coastal region. The societies are mainly dependent on freshwater. Spatial Distribution of seawater intrusion has been studied using Geographic Information System (GIS) technique. In this research, 57 samples of groundwater were collected from 9 sub-districts of Banda Aceh. A portable Global Positioning System (GPS) was used to collect the coordinates of each sample site. This research aimed to analyse and generate the spatial distribution of seawater intrusion in Banda Aceh coastal region from the measurement of groundwater Electrical Conductivity (EC) and Total Dissolved Solids (TDS) values in the fields. The EC and TDS were used as indicators to assess the potential of seawater intrusion in the coastal aquifers. The results indicated that spatial distribution of seawater intrusion scattered in northern part of Banda Aceh. However, the analysis and measurements showed that the extent of EC and TDS values varied prominently across these sites, with the maximum EC value of 6.270 μS cm-1 and TDS value of 4.420 mg l-1 found at Neusu Aceh Village in Baiturrahman sub-district. Moreover, the minimum EC and TDS values of 217 μS cm-1 and 100 mg l-1, respectively, found at Mulia Village in Kuta Alam sub-district.