Delineating the groundwater protection zone (GPZ) around a water supply plant in Bekasi, West Java']Java, Indonesia

The escalating community demands for water supply in urban areas lead to overexploitation on groundwater and worsening the condition of the resources. These exploitation activities will affect the quality, quantity, and continuity (QQC) of groundwater, especially those that are produced as the resource for the water supply industry. The study area is a water supply industry plant located in Bekasi, West Java, Indonesia, that uses groundwater originating from the Bekasi-Karawang Groundwater Basin. Proper management is needed to maintain the QQC of the groundwater, and one of the steps in pursuing it is with the Groundwater Protection Zone (GPZ) delineation. The aim of this study is to delineate the GPZ in the study area based on the natural conditions and the conceptual hydrogeological models. The method used to delineate the GPZ is groundwater flow modelling. As a result, this study identifies the unconfined and confined aquifers systems at the plant, while the groundwater extraction is only sourced from the confined aquifer. Our findings reveal that the groundwater in both unconfined and confined aquifers generally flows in a south-north direction with the travel time varying from 25 days to 133 years. The GPZ resulted for the water supply plant consists of the production well protection zone and the recharge area protection zone. This study also suggests recommendations for groundwater management in the GPZ based on the source of contaminants.