Strategic Planning of Urban Water Supply Systems in Responses to Rapid Urbanization: A Case Study of Bandar Lampung, Indonesia

Urban water supply systems in rapidly growing cities face major challenges in sustainability, efficiency, and equity, particularly in developing countries. Bandar Lampung, a fast-growing coastal city in Indonesia, has witnessed significant urban expansion, putting pressure on its aging water infrastructure. In response, the city government developed the Master Plan for Drinking Water Supply System (RISPAM) 2022–2042 to guide long-term water supply planning and service improvements. This study investigates the strategic elements of the RISPAM using a case study approach. A mixed-methods methodology was applied, integrating quantitative analysis of demographic and water demand projections, spatial assessment of service coverage, and qualitative evaluation of institutional and financial frameworks. Data were collected from local government reports, geospatial records, and expert consultations. Results show that only 29% of the population has access to piped water, with high technical and non-technical water losses. The RISPAM outlines phased infrastructure expansion, prioritization of investment, and protection of raw water sources through integrated land use planning. It also promotes performance-based public–private partnerships to improve service efficiency. The alignment of water supply planning with sanitation and spatial development indicates a shift toward holistic urban water governance. This study concludes that adaptive and integrated strategic planning is essential for ensuring resilient and equitable water services in rapidly urbanizing regions of the Global South.