A Phenomenon of Disparity Between Regional Spatial Planning and Actual Land Use in the Citarum River Corridor, Indonesia

The Citarum River in Indonesia is a sensitive and strategic area and is known as the dirtiest river in the world. The root of the problem lies in the existence of gaps along the corridor that are not subject to regional spatial plan (RSP). This study aims to (1) present empirical data illustrating these spatial discrepancies, and (2) analyse the underlying factors contributing to them. A spatial analytical approach was employed, integrating geospatial technologies and an Autel EVO 2 Pro V3 drone, alongside questionnaire surveys based on multi-criteria decision analysis (MCDA) (37 respondents) and in-depth interviews with local communities (35 respondents). The analysis of Sector 3 exhibited the highest disparity (49.85%) in gap area coverage, while Sector 1 showed the lowest (9.41%). A comprehensive investigation was conducted using MCDA to examine the underlying causes of these discrepancies. The findings indicate that economic, environmental and socio-demographic factors; public knowledge of RSP; the role of RSP; and community engagement with RSP are the root causes of the observed disparities along the Citarum River corridor (Sectors 1–4). We recommend aligning RSP with actual geospatial conditions; adopting adaptive zoning; enforcing laws; and enhancing public outreach for sustainable Citarum River management.