Author(s): Donghwi Jung
Linked Author(s): Donghwi Jung
Keywords: Population decline Drinking water distribution systems (DWDSs) Multi-phase planning Uncertainties
Abstract: Over the past decade, Asian countries have been experiencing low fertility rates -- reaching as low as 0.73 in South Korea and below 1.5 in several others -- due to economic pressures and shifting lifestyles. This demographic shift has triggered various socio-economic problems such as population aging and regional depopulation, which, in turn, renders many civil infrastructures redundant. Among these, drinking water distribution systems (DWDSs) face unique challenges, as water demand is directly influenced by population size and composition. Adapting rural DWDSs to declining and shifting populations requires modifications such as shutting down systems in depopulated areas and reconfiguring operational schemes to accommodate changes in demand distribution. Addressing this involves tackling a complex, multi-phase construction and modification problem under significant uncertainties. This study introduces a multi-phase planning approach for DWDSs, specifically designed to respond to future population decline and its associated impacts. The proposed approach begins by identifying the most critical uncertainties in planning, which are then used to generate future scenarios. The planning horizon is divided into multiple periods beginning with the first period that focuses on decisions applicable across all scenarios. The proposed multi-phase planning framework provides a practical tool for city planners and water system decision-makers, enabling them to systematically compare planning alternatives and navigate uncertainties associated with future demographic shifts.
Year: 2025