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. ... Read more

During the last decades, the role of data as a vital resource that enhances decision-making and supports efficient systems operation has become evident, with a growing number of companies viewing data as a key organizational aspects that has to be properly managed, instead of an operational side-product. At the same time, drinking water systems increase in complexity and feature smart sensors, which in turn leads to data-richer operation environments for the water services. Given this challenging context, the often-overlooked factor of ensuring high data quality and preventing errors in data streams becomes increasingly important. In this chapter the current data validation techniques, challenges and best practices of the Dutch drinking water companies is presented. ... Read more

A drinking water distribution system (DWDS) is a critical and a costly asset with a long lifetime. Drinking water demand is likely to change in the coming decades. Quantifying these changes involves large uncertainties. This paper proposes a stress test on the robustness of existing DWDS under changing drinking water demands. The stress test investigates the effects of extreme but plausible demand scenarios on the network performance. Two layouts, one conventional looped designed for fire flows and one designed as a self-cleaning, were tested. For 12 demand scenarios, diurnal patterns were simulated with the end-use model SIMDEUM. The performance of the network was evaluated on three criteria: (1) network pressure, (2) water quality, and (3) continuity of supply. Although the self-cleaning layout had higher head losses, it performed better regarding water quality than the conventional layout. Both networks are robust to the extremities of drinking water demands. The stress test is useful to quantify the performance range of the DWDS. For non-Dutch locations, the criteria and scenarios can be adapted to local conditions ... Read more

Recent studies have indicated that wastewater contains relatively large amounts of thermal energy. Recovering this thermal energy can be used to decrease the CO2 footprint of the water cycle. This paper describes the development of a model to simulate the heat balance and predict the temperature in a sewer system. The model can be used to estimate the recoverable thermal energy and its dynamics. The model was verified with field data. It was concluded that the model is a powerful and accurate tool to simulate the heat balance of a sewer system at the urban district level. It was found that the recoverable heat show highly dynamic patterns, directly related to water consumption patterns. The recoverable heat depends on technical aspects as well as regulations for maximum acceptable temperature differences due to heat abstraction. ... Read more