<![CDATA[Background: The coastal area of North Jakarta faces serious risks of groundwater table decline, seawater intrusion, and water quality degradation due to continuous groundwater extraction. Previous studies indicate that the aquifer system in North Jakarta consists of heterogeneous coastal alluvial deposits, including sand, silt, clay, and gravel. This condition causes groundwater potential to vary across locations. This study aims to analyze the potential availability of groundwater in Kalibaru Urban Village, Kampung Susun Akuarium Penjaringan, and Rusunawa Marunda. Methods: This study applied the Very Low Frequency Electromagnetic (EM-VLF) interpretation method to identify saturated zones beneath the surface. Field data included groundwater table depth, aquifer thickness, lithology, permeability factors, specific yield, salinity, and well measurements. Findings: Kalibaru Urban Village shows the highest estimated groundwater potential among the three sites, with a potential groundwater-bearing zone at 12–45 m depth and a Darcy-based relative total of 51.29 m³/day. Rusunawa Marunda also shows potential groundwater-bearing zones at approximately 42–59 m. The variation in estimated groundwater-flow potential is associated with differences in interpreted depth, thickness, lithology, specific yield, and EM-VLF-derived salinity indicators. Conclusion: Groundwater bearing conditions remain locally indicated at the three study sites. However, groundwater use should be carefully limited because coastal areas are vulnerable to salinity, contamination, seawater intrusion, and groundwater-table decline. Government agencies and local communities need to strengthen groundwater-level monitoring, direct water-quality testing, pumping control, piped-water services, and rainwater harvesting. Novelty/Originality of this article: This study provides an EM-VLF-based assessment of groundwater potential at three coastal locations in North Jakarta. It also connects subsurface technical findings with the need for site-specific groundwater management strategies.]]>
