Assessing the carbon footprint of drinking water supply system in Indonesia: A case study of the Rebana Metropolitan Area

Abstract

The development of the Rebana Metropolitan Area in the northern region of West Java aims to improve the economy in the area with improved infrastructure, including safe drinking water provision through a sustainable drinking water supply system (SPAM) that aligns with low-carbon development in Indonesia. This study presents a comprehensive assessment of the carbon footprint associated with SPAM. A dynamic system modeling approach was employed to calculate SPAM’s carbon footprint, considering key activities such as drinking water supply through piped networks and wells, bottled water distribution, potable water provision through refillable drinking water depots, and drinking water boiling. The model was calibrated and validated using data from Indramayu Regency, demonstrating its accuracy with an RMSPE value of 0.03% for the population and 4.89% for water treatment plant production capacity. By utilizing data from industrial zones (KPI) Patrol and Losarang, the model simulations revealed that under business as usual (BAU) conditions, the projected carbon footprint of SPAM in 2040 was 332,194 tCO2eq. To explore effective intervention strategies, three scenarios (I, II, and III) were simulated, incorporating different rates of wastewater recycling—10%, 20%, and 30% by 2030, respectively. The results demonstrated that implementing these scenarios would lead to reduced SPAM’s carbon footprints in 2040, with projected values of 283,275 tCO2eq, 246,586 tCO2eq, and 225,184 tCO2eq for scenarios I, II, and III, respectively. Bottled water exhibited the highest carbon footprint per unit volume of 28.847 kgCO2eq/m3.