Scholarly record
RELIABILITY AND RESILIENCE ASSESSMENT OF SEWAGE PUMPING STATION IN OPERATING CONDITIONS
Abstract
Climate change and the increasing frequency of extreme rainfall events impose additional stress on urban drainage infrastructure and particularly on wastewater pumping stations operating within combined sewer systems. This study investigates the operational performance of an existing wastewater pumping station located in northeastern Bulgaria and subjected to significant hydraulic loading caused by permanent external inflows and stormwater runoff. The assessment combines field observations, SCADA-derived operational data, hydraulic system analysis, and a reliability-resilience framework developed specifically for pumping station operation under variable hydraulic loading conditions. The methodology incorporates hydraulic operating states, failure-state definition, reliability and resilience indicators, and annual operating frequencies derived from SCADA records. The results indicate that the pumping station retains approximately 22.8% residual hydraulic capacity under normal operating conditions. However, during wet-weather periods, which account for approximately 35% of the monitored year, the inflow approaches the maximum pumping capacity, resulting in a hydraulic reliability ratio of 0.998 and a resilience index close to zero. When annual operating frequencies are considered, the weighted hydraulic resilience decreases to approximately 14.7%, demonstrating the dominant influence of rainfall-driven operation on system performance. The proposed methodology enables quantitative assessment of WWPS hydraulic performance using SCADA-derived operating frequencies and hydraulic capacity indicators.
Publication details
References13
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