A DEA-Based Water Distribution Flushing Planning for Prioritizing High-Risk Pipes and Blocks

Flushing planning requires utilities to prioritize pipes and service blocks using heterogeneous structural and hydraulic information. This study proposes a data envelopment analysis (DEA)-assisted framework that links pipe-level screening, service-block prioritization, and candidate flushing-segment planning. The framework separately evaluates sedimentation and detachment conditions using input-oriented Banker–Charnes–Cooper (BCC) models based on seven indicators, while avoiding the need to prescribe a common expert-defined weighting vector. The framework was applied to a real water distribution system with 481 pipes and 394 junctions, identifying 88 sedimentation-priority pipes and 12 detachment-priority pipes. Length-weighted aggregation within the existing block structure ranked Blocks 1, 7, 2, and 4 highest, whereas length-normalized analysis identified Block 2 as having the greatest concentration of priority pipes. The leading four-block group remained unchanged across the tested pipe-length exponents, and the top-12 detachment set was retained when the velocity-difference screening level was varied from 0.5 to 2.0 m/s. Additional model-form, preprocessing, indicator-omission, and equal-weight comparisons were used to characterize the sensitivity of pipe-level priorities. Finally, existing valve and hydrant locations were used to delineate five candidate flushing segments in a representative block. The framework provides a systematic basis for directing detailed hydraulic verification and field implementation.