A Proposal of Optimal Sampling Design Using Infrastructure Modularity

Planning of pressure observations/meters in terms of spatial distribution and number is named sampling design. In the past, the hydraulic model calibration was the main driver of the sampling design. Today, water utilities are interested in system pressure monitoring for hydraulic system analysis and management with respect to other technical purposes as for example detection of anomalies (burst leakages and anomaly head losses) and service quality with respect to customers. In recent years, the optimal location of flow observations/meters, related to design of optimal district metering areas, has been faced considering optimal network segmentation and the modularity index using a multi-objective strategy. The original modularity index from the studies of the complex network theory was transformed to be WDN-oriented. Consistently, this paper proposes a new way to perform the sampling design using newly developed sampling-oriented modularity-based metrics. The strategy optimizes the location of the pressure meters based on network topology creating pressure district metering areas, i.e. it returns the optimal location of the nodal pressure meters defining "pressure DMAs". The multi-objective optimization problem minimizes the cost of newly installed meters while maximizing the sampling-oriented modularity metrics. The battle of background leakages assessment water network (BBLAWN) allows presenting and discussing the proposed sampling design methodology. (C) 2016 The Authors.