A model to support decision systems regarding the quantification, location and opening adjustment of control valves in a network system, with the main objective to minimise pressures and consequently leakage levels is developed. This research work aims at a solution that allows simultaneously optimising the number of valves and its location, as well as valves opening adjustments for simulation in an extended period, dependently of the system characteristics. EPANET model is used for hydraulic network analysis and two operational models are developed based on the Genetic Algorithm optimisation method for pressure control, and consequently leakage reduction, since a leak is a pressure dependent function. In these two modules, this method has guaranteed an adequate technique performance, which demands a global evaluation of the system for different scenarios. A case study is presented to show the efficiency of the system by pressure control through valves management.

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Methods to detect outliers in network flow measurements that may be due to pipe bursts or unusual consumptions are fundamental to improve water distribution system on-line operation and management, and to ensure reliable historical data for sustainable planning and design of these systems. To detect and classify anomalous events in flow data from district metering areas a four-step methodology was adopted, implemented and tested: i) data acquisition, ii) data validation and normalization, iii) anomalous observation detection, iv) anomalous event detection and characterization. This approach is based on the renewed concept of outlier regions and depends on a reduced number of configuration parameters: the number of past observations, the true positive rate and the false positive rate. Results indicate that this approach is flexible and applicable to the detection of different types of events (e.g., pipe burst, unusual consumption) and to different flow time series (e.g., instantaneous, minimum night flow).

Strategic asset management of urban water infrastructures jointly deals with assets of diverse nature, useful life, cost, age and condition. Service sustainability requires a sound long-term planning, which needs assessing, among other aspects: the value of the infrastructure over time; the need for reinvestments; the impact of long-term re-investment policies. The infrastructure value index (IVI) was proven to be a powerful modelling tool for combined long-term planning of linear and vertical assets. An open-source software enables IVI assessment for both asset-by-asset detailed inventory and for simplified cohort-based infrastructure description. This paper presents the formulation, discusses the underlying assumptions and applicability, and illustrates its use for strategic planning

In countries suffering from chronic water shortages, water distribution systems are often operated on an intermittent basis, leaving them unpressurised and allowing ingress of contaminated groundwater, particularly in areas lacking sewerage systems. The periods of stagnation can promote microbial regrowth, further compromising water quality. On the other hand, peaks in pressure and velocity in the pipe network lead to biofilm detachment events, thus releasing microbial cells that may escape the regular quality monitoring procedures and thus increase risk for the consumer. Finally, intermittent supply requires consumers to store water in household storage tanks, which often encourage bacterial regrowth. This paper reports on research undertaken in Jordan, Lebanon, Palestine, the UK and Portugal, which provided an improved understanding of the factors controlling bacterial concentrations in intermittent supplies, and presents an overview of the most important aspects of water quality control in intermittently operated networks.

Water services are a strategic sector of large social and economic relevance. It is therefore essential that they are managed rationally and efficiently. Advanced water supply and wastewater infrastructure asset management (IAM) is key in achieving adequate levels of service in the future, particularly with regard to reliable and high quality drinking water supply, prevention of urban flooding, efficient use of natural resources and prevention of pollution. This paper presents a methodology for supporting the development of urban water IAM, developed during the AWARE-P project as well as an appraisal of its implementation in four water utilities. Both water supply and wastewater systems were considered. Due to the different contexts and features of the utilities, the main concerns vary from case to case; some problems essentially are related to performance, others to risk. Cost is a common deciding factor. The paper describes the procedure applied, focusing on the diversity of drivers, constraints, benefits and outcomes. It also points out the main challenges and the results obtained through the implementation of a structured procedure for supporting urban water IAM.