Groundwater vulnerability assessment and mapping in shallow groundwater

Abstract

The increasing population density can contaminate groundwater. So far, groundwater is still the primary source to fulfill clean water and drinking water in Muntilan, Salam, and Ngluwar Sub-District. Studies on groundwater vulnerability are essential to minimize the contamination risks as a piece of basic information for land use planning. This research aims to assess groundwater vulnerability in Muntilan, Salam, and Ngluwar Sub-District. The simple vertical vulnerability (SVV) method with GIS was selected to develop a groundwater vulnerability map. The parameters of this method consist of the type of soil/rock, the thickness of the water-unsaturated zone, and the recharge value. The results show that the research area can be divided into three vulnerability classes: Very low, moderate, and high groundwater vulnerability. Very low groundwater vulnerability has a value of more than 70 with very high protection effectiveness. The class is distributed in Muntilan and Salam Sub-Districts. Moderate groundwater vulnerability has a value less than 35 to 65 with moderate protection effectiveness, and high groundwater vulnerability has a value ranging from 24 to 35 with low protection effectiveness. Both of the class is evenly distributed in Muntilan, Ngluwar and Salam Sub-Districts.