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The ongoing COVID-19 pandemic is, undeniably, a substantial shock to our civilization which has revealed the value of public services that relate to public health. Ensuring a safe and reliable water supply and maintaining water sanitation has become ever more critical during the pandemic. For this reason, researchers and practitioners have promptly investigated the impact associated with the spread of SARS-CoV-2 on water treatment processes, focusing specifically on water disinfection. However, the COVID-19 pandemic impacts multiple aspects of the urban water sector besides those related to the engineering processes, including sanitary, economic, and social consequences which can have significant effects in the near future. Furthermore, this outbreak appears at a time when the water sector was already experiencing a fourth revolution, transitioning toward the digitalisation of the sector, which redefines the Water-Human-Data Nexus. In this contribution, a product of collaboration between academics and practitioners from water utilities, we delve into the multiple impacts that the pandemic is currently causing and their possible consequences in the future. We show how the digitalisation of the water sector can provide useful approaches and tools to help address the impact of the pandemic. We expect this discussion to contribute not only to current challenges, but also to the conceptualization of new projects and the broader task of ameliorating climate change.

Primary screening is gaining interest as a method to achieve removal performances comparable to primary clarification while reducing the footprint and increasing operational elasticity. Aeration efficiency indicators in a pilot sequential batch reactor (SBR) and a full scale water resource recovery facility (WRRF) were investigated after the implementation of rotating belt filters/screens (RBF). To compare the impact between screened (350 μm) and nonscreened primary influent, two identical treatment lines were monitored using off‐gas and respirometric measurements. The study provides the first result on improved oxygen transfer efficiency due to primary screening. Consistent aeration efficiency improvements of 27% and 20% between screened and nonscreened were obtained at pilot and full scale, respectively. Changes in aeration efficiency and carbon redirection were integrated into a set of models to investigate the primary screening impact on the WRRF energy balance. While the plant‐wide assessment for different scenarios improved the energy balance up to 15%, a detailed comparative analysis between various treatment schemes gained insight into the advantages and limitations of the energetic sustainability of primary screening. Practitioner points: Aeration efficiency improved 27% at pilot scaleAeration efficiency improved 20% at full scale.Use of primary screening can improve the energy balance up to 15Assessment of advantages and limitations of primary screening. [ABSTRACT FROM AUTHOR]

A water resource recovery facility sited in a region at a high elevation has experienced the effects of over-designing its blowers. In this case study, we used off-gas analysis and site-specific power tariffs to quantify actual process loading and air requirements, and we quantitatively evaluated various options for blower replacement or upgrade. Off-gas analysis mapped the oxygen uptake rate at the surface of the tank, suggesting that the tanks were not evenly loaded across their sections. The local cost of energy directly affects the return on the investment calculation and limits the available solutions. The payback of partial or complete blower replacement may not be justified even in the event of excessive aeration, and the sequencing of aeration system improvements including diffuser replacement, process controls, and blower modifications should be evaluated contemporaneously. PRACTITIONER POINTS: Off-gas analysis can be used to evaluate process loading imbalances by mapping the oxygen uptake rate. Alpha factors from off-gas testing are used in process models to evaluate air requirements and blower air demand. Comparative evaluation of blowers must be done considering the net present value of the status quo, upgrades, or replacement., (© 2024 The Author(s). Water Environment Research published by Wiley Periodicals LLC on behalf of Water Environment Federation.)