ABSTRACT Graph illustrating the application of Seawater Reverse Osmosis (SWRO) technology as a decentralized water supply system, converting seawater into safe drinking water through salt removal. Coastal regions worldwide are increasingly confronted with chronic water scarcity driven by seawater intrusion, climate variability, and the limited reach of centralized water infrastructure. While large-scale desalination has expanded rapidly over the past decades, its technological and economic configuration often excludes small coastal and island communities. Bridging this gap requires not merely technological advancement, but contextual adaptation of desalination systems to decentralized and resource-constrained settings. A case study of seven decentralized SWRO installations in coastal South Sulawesi illustrates the application of modular SWRO systems with multi-stage pretreatment, including KMnO4 pre-oxidation, multimedia filtration, and cartridge filtration, producing treated water that met national drinking water standards. Economic feasibility was evaluated, showing an operational expenditure (OPEX) of 0.0036 USD/L, which remains competitive with commercially available bottled water. Overall, the findings demonstrate that decentralized SWRO can move beyond technical feasibility toward operational sustainability when supported by modular design, context-specific pretreatment, and community-based management. By connecting global technological development with empirical field deployment, this study positions decentralized SWRO as a pragmatic and scalable pathway for strengthening coastal water security in developing regions.
Rifai et al. (Thu,) studied this question.