Lessons Learnt from the Application of MCDA Sorting Methods to Pipe Network Rehabilitation Prioritization

Abstract

Most water distribution networks were built a few decades ago, showing symptoms of deterioration. Additionally, current renewal rates are insufficient to overcome pipe networks’ continuous ageing process. The development of methodologies for assisting the definition of pipe rehabilitation, including which pipes, and when and what financial amounts to allocate to this activity, are of the utmost importance. These methodologies typically have to attend to several points of view, for which multicriteria decision analysis (MCDA) techniques may be used. The current paper demonstrates and discusses the application of two MCDA techniques—the ELECTRE TRI-C and FlowSort—to a real water distribution network. Both techniques allowed assigning every single pipe to a predefined priority category, although the ELECTRE TRI-C proved to be more effective. These approaches imply that the planning of investment needs is carried out based on individual pipes, but these approaches are not consistent with the actual rehabilitation projects. A clustering technique called affinity propagation, together with cost functions, were applied to define and quantify homogeneous rehabilitation units. Even so, the methodology did not prove to be rigorous enough for the selection of pipes to be rehabilitated. On the other hand, it proved effective to estimate annual budgets for rehabilitation.

Computational Tools for Supporting the Operation and Management of Water Distribution Systems towards Digital Transformation

“…A novel approach to support pipe rehabilitation has been developed to group network segments instead of grouping individual pipes and scheduling rehabilitation in a mediumand long-term perspective. This approach is divided into two main phases: the first is the definition of pipe grouping according to an available budget and contiguity (referred to as rehabilitation units), and the second is the interventions' scheduling overtime according to predefined criteria, defined by Caetano et al [30].…”

Application of the analytical hierarchy process for planning the rehabilitation of water distribution networks

“…Francisque et al (2014) developed a decision-making tool based on a risk approach and a hybrid genetic algorithm (HGA), named Water main Replacement Risk-based Model (WARRM) to priorities the rehabilitation of drinking water pipes. Other researchers have used machine learning model (Raspati et al, 2022) while several other researchers have applied at least one of the MCDM methods for planning the rehabilitation of WDN (Scholten, Scheidegger, Reichert, Mauer, & Lienert, 2014;Caetano, Carriço, & Covas, 2022).…”

Pipe renewal plan in water distribution network considering physical and operational risk factors: A hybrid MCDM-QSPM technique

“…In fact, it is concluded that the knowledge of experts can be as important as the numerical data in the policy making processes of any field in public services, like pipe renovation planning. Caetano et al (2022) prioritized the pipes of a drinking WDN to facilitate modification implementing the MCDM technique. It was attained that this type of planning affects the annual budget for WDN reconstruction.…”