Water leakage management by district metered areas at water distribution networks

The impact of the number of high temporal resolution water meters on the determinism of water consumption in a district metered area

Developments in data mining techniques have significantly influenced the progress of Intelligent Water Systems (IWSs). Learning about the hydraulic conditions enables the development of increasingly reliable predictive models of water consumption. The non-stationary, non-linear, and inherent stochasticity of water consumption data at the level of a single water meter means that the characteristics of its determinism remain impossible to observe and their burden of randomness creates interpretive difficulties. A deterministic model of water consumption was developed based on data from high temporal resolution water meters. Seven machine learning algorithms were used and compared to build predictive models. In addition, an attempt was made to estimate how many water meters data are needed for the model to bear the hallmarks of determinism. The most accurate model was obtained using Support Vector Regression (8.9%) and the determinism of the model was achieved using time series from eleven water meters of multi-family buildings.

Restructuring a Water Distribution Network through the Reactivation of Decommissioned Water Tanks

Water resource management is a topic of great environmental and social relevance, since water must be preserved and managed to avoid waste, providing high quality service at fair tariffs for the consumer, as imposed by the European Water Directive (2000/CE). In the rehabilitation of a water distribution network, it may be suitable to recover decommissioned water tanks, if any, rather than afford high construction costs to build new ones. In this case, the assessment of the residual service life of these concrete structures affected by steel bar corrosion is the premise for the design of new pipeline routes, connecting them. For this aim, rather than carrying tests that can accurately determine mechanical properties of the dismissed water tanks, it is possible to empirically estimate their level of degradation. Their conditions infer on the expected life of the restructured water distribution network. However, they allow the aqueduct to be used for its technical duration, assumed to be equal to the decommissioned water tanks residual service life in the case they do not require maintenance. Here, a simplified model for the assessment of the residual service life of decommissioned water tanks is first proposed and then applied to a case study, consisting of a part of the water network managed by “Ausino S.p.A. Servizi Idrici Integrati”, Cava de’ Tirreni, Italy. Once the service life is assessed, the QEPANET plugin is used in QGIS to speed up the design of the new pipeline routes in the georeferenced space, thus overcoming the limits offered by the classic EPANET solver.

An Improved Genetic Algorithm for Optimal Layout of Flow Meters and Valves in Water Network Partitioning

The paradigm of “divide and conquer” has been well used in Water Distribution Systems (WDSs) zoning planning in recent years. Indeed, Water Network Partitioning (WNP) has played an irreplaceable role in leakage control and pressure management; meanwhile it also has certain drawbacks, such as reduction of the supply reliability of the pipe network system and increased terminal dead water, as a result of the closure of the pipe section. In this paper, an improvement is made to the method proposed by Di Nardo et al. (2013) for optimal location of flow meters and valves. Three improvements to the genetic algorithm are proposed in this work for better and faster optimization in the dividing phase of WNP: preliminary hydraulic analysis which reduces the number of decision variables; modifications to the crossover mechanism to protect the superior individuals in the later stage; and boundary pipe grouping and mutation based on the pipe importance. The objective function considers the master–subordinate relationship when minimizing the number of flow meters and the difference of hydraulic state compared to original WDS. Another objective function of minimizing the deterioration of water quality compared to original WDS is also evaluated. The proposed method is applied for the WNP in a real WDS. Results show that it plays an effective role in the optimization of layout of the flow meters and valves in WNP.