Resilience evaluation of a multi-reservoir transmission network using hydraulic and graph-theoretic metrics: A case study of Qatar's national water network

Resilience assessment of water distribution networks is increasingly critical in regions facing extreme climate pressures and high supply-demand variability. Building on prior work that evaluated node-level resilience in a single-reservoir benchmark, this study applies a hydraulically informed, time-dependent, graph-theoretic framework to Qatar's national multi-reservoir transmission network comprising five primary reservoirs (MRPS) and twenty-six secondary reservoirs (SRPS). The analysis integrates 196 hours of extended-period simulation and 700 candidate flow paths per hour, filtered to the k = 30 most hydraulically distinct routes for each SRPS. Three complementary path-based indicators - hydraulic connectivity, supply entropy, and temporal stability - quantify efficiency, redundancy, and reliability, respectively. Results reveal large inter-node variability. While some SRPS receive up to 21 feasible supply paths from more than one MRPS, others characterized by high-demand reaching 2,300- 2,500 L/s depend on a single MRPS source, exhibiting the lowest composite resilience due to limited redundancy and unstable path dynamics. Composite resilience rankings highlight SRPS20 and SRPS25 as the most vulnerable nodes, indicating priority candidates for redundancy upgrades. The findings demonstrate the utility of dynamic, graph-hydraulic metrics in identifying critical weaknesses and guiding resilience planning for large-scale, multi-source water systems.