Hydrogeophysical Characterization of Groundwater Distribution in the Upper Citarum River Basin Using DC Resistivity Method Kusnahadi Susanto (a,b*), Salsabila Putri (c), Kartika H Kirana (a)
a)Dept. Geophysics, Universitas Padjadjaran
Jalan Raya Bandung-Sumedang KM. 21 Jatinangor, Indonesia
b) Center of Citarum Research (CCR-Unpad)
Jalan Raya Bandung-Sumedang KM. 21 Jatinangor, Indonesia
*k.susanto[at]unpad.ac.id
c)Undergraduate program of Geophysics, Universitas Padjadjaran
Jalan Raya Bandung-Sumedang KM. 21 Jatinangor, Indonesia
Abstract
Groundwater is a critical natural resource increasingly impacted by population growth, land-use changes, and intensive industrial activities, including those within the Citarum River Basin (CRB), Indonesia. Over the past decade, the CRB has undergone a significant transformation, from one of the most polluted rivers to a progressively cleaner system. These surface water improvements are hypothesized to correlate with subsurface groundwater conditions. This study investigates the depth and spatial distribution of the groundwater table in the Upper Citarum Basin using the Direct Current (DC) resistivity method with a Schlumberger array configuration. Geophysical data were acquired along four survey lines across the Citarik and Cikeruh sub-watersheds using an AGI SuperSting R8/IP resistivity meter. The acquired data were processed with AGI EarthImager 2D software to produce two-dimensional resistivity profiles of the subsurface. The results delineated three major resistivity zones: (1) low-resistivity zones (2-6 Ohm m), interpreted as saturated clay layers- (2) medium-resistivity zones (6-15 Ohm m), associated with sandy clay deposits- and (3) high-resistivity zones (15-35 Ohm m), corresponding to compact, relatively dry clay. The groundwater table was identified at depths ranging from approximately 0.6 to 17 meters. These findings offer a preliminary hydrogeological framework of the Upper Citarum Basin, providing a valuable baseline for future groundwater monitoring and sustainable water resource management.
Keywords: Groundwater, Resistivity, Upper Citarum River, Hydrogeophysical survey
