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The role of a drinking water distribution network (DWDN) is to supply high-quality water at the necessary pressure at various times of the day for several consumption scenarios. Locating and identifying water leakage areas has become a major concern for managers of the water supply, to optimize and improve constancy of supply. In this paper, we present the results of field research conducted to detect and to locate leaks in the DWDN focusing on the resolution of the Fixed And Variable Area Discharge (FAVAD) equation by use of the prediction algorithms in conjunction with hydraulic modeling and the Geographical Information System (GIS). The leak localization method is applied in the oldest part of Casablanca. We have used, in this research, two methodologies in different leak episodes: (i) the first episode is based on a simulation of artificial leaks on the MATLAB platform using the EPANET code to establish a database of pressures that describes the network's behavior in the presence of leaks. The data thus established have been fed into a machine learning algorithm called random forest, which will forecast the leakage rate and its location in the network; (ii) the second was field-testing a real simulation of artificial leaks by opening and closing of hydrants, on different locations with a leak size of 6 and 17 L s−1. The two methods converged to comparable results. The leak position is spotted within a 100 m radius of the actual leaks.

A reservoir management approach requires, regularly, an update of its parameters in order to assure that the reservoir continue to fulfill its role without major failure. In fact, the performance criteria are widely associated with to optimization as tools to assess and compare optimized and initial approaches. In this study, we analyzed the ability of six performance criteria to assess and compare, correctly, six management approaches of the Bin El Ouidane-Ait El Ouarda complex, under varying conditions. Five of the six compared approaches are results of a double optimization phase using the Genetic Algorithm. And the sixth represents the current management approach of the complex. The analysis of the obtained results via the principal component analysis method shows that the optimized approaches are performing better according to all criteria, and negative management practices of the current approach were detected. Additionally, remarks concerning the reliability of the studied criteria were underlined: the very high dependency of the criteria values to the conditions of calculation, the necessity to use various criterion because the use of only one can alter the comparison, the necessity to report in addition to the criterion value its calculation conditions, and the sustainability criterion tends to give an implicit weight coefficient to the parameter having the low value. This paper novelty is that it gave an application example of guidelines to follow and precautions to consider, in order to assess and compare reservoir management approaches, taking into account the question of representativeness of the performance criteria.

L'urbanisation entraine des modifications importantes du cycle hydrologique naturel par l'augmentation des surfaces impermeables et par la creation de reseaux de drainage pour permettre l'evacuation et/ou le stockage des eaux de pluie. La conception des reseaux de drainage urbain repose generalement sur l'analyse des historiques de pluies disponibles. Le point commun entre les methodes de conception d`un reseau de drainage urbain est le recours a des modeles Pluie-Debit pour tenter de decrire le comportement d'un bassin versant urbain vis-a-vis de la " grandeur pluie " etant la base du cycle hydrique dans la ville [Mailhot et al. , 2005]. Or, dans un contexte de Changement Climatique (CC), la variation de l'intensite et de la frequence des precipitations constitue une incertitude majeure qui conditionne la fiabilite et les limites des resultats de ces modeles [Oudin, 2008]. Cet article a pour objectif de :1) Decrire et evaluer qualitativement les principales sources d'incertitudes pour un modele Pluie-Debit en milieu urbain dans un contexte de CC ;2) Analyser la fiabilite des resultats des modeles Pluie - Debit vis-a-vis de la recurrence des evenements pluvieux extremes modifiee par le CC et ses effets attendus ;3) Donner un apercu sur les pratiques classiques au niveau du dimensionnement des reseaux de drainage urbain tant au niveau national qu'au niveau de pays avances dans ce domaine ;4) Presenter des approches nouvelles et innovantes; testees dans certains pays developpes; en vue d'une amelioration des methodes de conception classique des reseaux de drainage urbain, pour tenir compte du nouveau contexte climatique attendu pour les prochaines decennies.