Water temperature is often monitored at water sources and treatment works; however, there is limited monitoring of the water temperature in the drinking water distribution system (DWDS), despite a known impact on physical, chemical and microbial reactions which impact water quality. A key parameter influencing drinking water temperature is soil temperature, which is influenced by the urban heat island effects. This paper provides critique and comprehensive summary of the current knowledge, policies and challenges regarding drinking water temperature research and presents the findings from a survey of international stakeholders. Knowledge gaps as well as challenges and opportunities for monitoring and research are identified. The conclusion of the study is that temperature in the DWDS is an emerging concern in various countries regardless of the water source and treatment, climate conditions, or network characteristics such as topology, pipe material or diameter. More research is needed, especially to determine (i) the effect of higher temperatures, (ii) a legislative limit on temperature and (iii) measures to comply with this limit.

The purpose of the research is to assess chlorine concentration in WDS using statistical models based on ANN in combination with Monte-Carlo. This approach offers advantages in contrast to the generally use methods for modeling of chlorine decay in drinking water systems until now. The model was tested on one specific location using the hydraulic and water quality parameters such as flow, pH, temperature, etc. The model allows forecasting chlorine concentration at selected nodes of the water supply system. The results obtained in these selected nodes allow then to compare the chlorine concentration with EPANET in the system under assessment

The paper presents the methodology for determining the operating and technical indicators for a preliminary assessment of the elements of water supply system (WSS) such as water treatment plants. The necessary data and system of technical indicators (TI) evaluation using the multi-objective optimization and Failure Mode and Effects Analysis (FMEA) are defined. The proposed methodology allows for the selection and ranking of WSS critical elements for more detailed analyses and suggestions of the type of renewal, including the estimated financial costs. Water treatment plants can be assessed by means of the specific part of the methodology. With respect to the water treatment plants the authors of the methodology realize that it is hard to generalize the entire audit since there are many types of water treatment plants as well as technological elements used. The proposed set of assessment indicators is based on the function of the water treatment plant, i.e. production of drinking water in the required quantity and quality. When assessing the technical condition of the water treatment plant this facility may not be viewed simply in structural and technical terms but it is absolutely necessary and much more important to assess it in technological terms

Pressure management is the basic step of reducing water losses from water supply systems (WSSs). The reduction of direct water losses is reliably achieved by reducing pressure in the WSSs. There is also a slight decrease in water consumption in connected properties. Nevertheless, consumption is also affected by other factors, the quantification of which is not trivial. However, there is still a lack of much relevant information to enter into this analysis and subsequent decision making. This article focuses on water consumption and its prediction, using regression models designed for an experiment regarding an administrative building in the Czech Republic (CZ). The variables considered are pressure and climatological factors (temperature and humidity). The effects of these variables on the consumption are separately evaluated, subsequently multidimensional models are discussed with the common inclusion of selected combinations of predictors. Separate evaluation results in a value of the N₃ coefficient, according to the FAVAD concept used for prediction of changes in water consumption related to pressure. The statistical inference is based on the maximum likelihood method. The proposed regression models are tested to evaluate their suitability, particularly, the models are compared using a cross-validation procedure. The significance tests for parameters and model reduction are based on asymptotic properties of the likelihood ratio statistics. Pressure is confirmed in each regression model as a significant variable.

The project CARE-W presented in this paper deals with the public water supply networks and their problems of ageing such as structural failures, hydraulic insufficiencies, leakage, deteriorating water quality and increasing maintenance cost that impact on an urban environment. The ultimate goal of the project is to develop a suite of tools, which provide the most cost-efficient system of maintenance and repair of water distribution networks, with the aim to guarantee a security of water supply that meets social, health, economic and environmental requirements. The paper comprises a description of the project work-packages, which include: a control panel of Performance Indicators (PIs) for rehabilitation;a description of technical and statistical tools assessing and forecasting some of the PI;a procedure to define the best choice for annual rehabilitation programming;a procedure to define the best strategy of planning rehabilitation investments (at long term, 10 to 20 years);a software, combining the above products with a common database, tested and evaluated by several test cities. CARE-W is aimed at utilities for water supply systems, operating companies, local authorities, financial institutions and national regulators. It is supported by the European Commission under the fifth framework programme.

To ensure sustainability and reliability of water supply infrastructure, we must apply a basic pre-condition, which is, its continual renewal. For renewal planning, there are many methods, techniques and software tools for decision support, but most of them, in many cases, focus only on water mains. Water supply systems, however, consist of different parts and structures than just water pipes. It is therefore not appropriate to invest in the renewal planning only in relation to one part of the water supply infrastructure. The knowledge of the current technical condition of the water supply infrastructure is crucial to maintain its planned performance and optimise its maintenance and renewal. Effective detailed evaluation of the technical condition requires deployment of specialists, reliable database, considerable amount of time and instrumentation and software. Therefore, it is preferable to perform the first rapid and efficient preliminary identification of problematic areas and elements of water supply systems. This paper presents the methodology and the Technical Energy Audit (TEA Water), the effective preliminary assessment of the technical state of water supply systems (WSS). The paper presents the structure of the proposed technical indicators, the method of their determination and evaluation, including the presentation of case studies of implementing the methodology and software tool in the Czech Republic