Integrated basin-based wastewater management system for water pollution control in an enclosed waterbody of the upper Citarum River Basin, Indonesia: Case study of Saguling Reservoir

The importance of implementing an integrated basin‐based wastewater management dealing with water pollution for the Upper Citarum River (UCR) Basin, Indonesia, has implications for the Saguling Reservoir, which was investigated in this study. This study incorporates a comparative assessment of stage‐type models in other systems as a reference, focusing on the impacts of combined measures on pollutant load reduction. Analysis of pollutant loads from various sectors was initially addressed to identify major contributors to the pollutant load in the basin and the Saguling Reservoir. Focus on initial improvement of selected pollutant targets by applying such an integrated approach with respect to domestic waste water was subsequently addressed. In elaborating a comparative assessment, case studies of Japanese‐ and Thai‐type models were analysed from a technological perspective. This aspect addressed the pollutant load reduction by comparing the input–output of treatment systems in both models. The result suggests that, in the case of a high reliability of both structural and non‐structural measures, an independent one‐stage measure could be sufficient to achieve a certain target of pollutant load reduction, as exhibited by the Japanese case study. On the other hand, when both measures are still limited and have relatively lower performance, a two‐stage measure is required. Accordingly, a two‐stage collaboration among limited treatment measures could be a ‘lesson learned’ for the UCR Basin. Nevertheless, incorporation of other aspects, such as a dual‐support of socio‐economic framework, also is required to endorse this technological aspect. Further integration requires future investigation.