Diagnosing operational functional resilience of regional water networks: A pressure-structure-function-response framework

Study region Taizhou, a coastal city in southeastern China, has developed an interconnected regional water network linking multiple local sources, transfer corridors, and service areas. The system is exposed to variable water availability, growing demand, and potential capacity losses in key conveyance components. Study focus This study proposes a Pressure-Structure-Function-Response (PSFR) framework to diagnose the operational functional resilience of regional water networks. The framework integrates supply-demand pressure, directed network structure, capacity-reduction disturbances, service retention, post-disturbance reallocation, recovery, and residual shortage risk. It is applied to the Taizhou water network under three structural scenarios, five supply-demand pressure scenarios, and four disturbance levels to evaluate system-level resilience and component criticality. New hydrological insights for the region Network interconnection improves service coverage, alternative allocation routes, and reconfiguration capacity, thereby increasing operational functional resilience. However, these gains decline under dry-flow and high-demand conditions because source availability and downstream delivery interfaces become binding constraints. As the network becomes more interconnected, component criticality shifts from local water sources toward regional backbone transfer corridors, while terminal service links remain persistent bottlenecks. The PSFR framework therefore explains not only whether resilience changes, but also where recovery is constrained, providing a practical basis for network reinforcement, emergency water allocation, and resilience-oriented planning in regional water-supply systems.