Cost–Benefit Prediction of Asset Management Actions on Water Distribution Networks

Abstract

The potential costs and benefits of a combination of asset management actions on the water distribution network are predicted. Two types of actions are considered: maintenance actions and renewal actions. Leak detection and reparation of failures on connections and pipes define the set of potential maintenance actions to be carried out. Renewal actions concern connections, pipes, and meters. All these actions represent the model’s decision variables in order to determine a trade-off between two objectives: (i) the maximization of the water efficiency rate and (ii) the minimization of the total cost of actions to be carried out on the water system. The assessment of objective functions is ensured by an artificial neural network (ANN) trained on a French mandatory database «SISPEA». A non-dominated sorting genetic algorithm (NSGA-II) is coupled to the ANN to reach the set of compromised solutions representing potential actions to achieve. Applied to a real water distribution system in the southeast of France, the proposed decision model indicates that the improvement of water efficiency rate (WER) in the short term requires increasing operation expenditures (OPEX), which represent 99% of the total cost. Results show the existence of a threshold effect that implies to use the budget in a certain way to improve performance. A potential solution can be chosen by the decision maker among the generated Pareto front with regard to the constraint on the budget and the targeted WER.

Advances in Modeling and Management of Urban Water Networks

“…In the field of WDSs, all works are numerical analyses, though most of them, i.e., [38][39][40]43,44], present models calibrated on the basis of experimental data. The methodologies adopted are multi-faceted, ranging from physically based modelling, [40,41,44,45], to GIS algorithms, [42], data-driven techniques, [38,39,43], graph-theory, [43], and optimization algorithms, [38,41,45].…”

“…Starting with WDSs, the first analyzed topic is asset management, which was dealt with by Nafi and Brans [38] by applying the bi-objective optimization to find optimal solutions in the trade-off between costs and efficiency in the WDS to a French WDS. ANNs trained on real data are used for the assessment of both objective function within the optimization process.…”

“…Nafi and Brans [38] predict the potential costs and benefits of a combination of asset management actions of maintenance and renewal in the WDS. The actions are treated as decisional variables in a bi-objective optimization aimed at finding solutions in the trade-off between cost and efficiency, to be minimized and maximized, respectively.…”

A New Method for Optimization of Water Distribution Networks While Considering Accidents

“…This objective is the annual cost composed of depreciation, and the annual energy cost of the pumping station. The annual cost is shown in Equation (1), which is the only equation considered for single-objective optimization. However, for the multi-objective optimization, the reliability objective of WDN should also be considered.…”

“…Water Distribution Networks (WDNs) form a part of the critical municipal infrastructure. These are very complex systems that require a high investment in their construction and maintenance [1]. Under normal conditions, a suitable WDN should be able to provide water with the required pressure.…”