The occurrence of human pathogenic viruses in aquatic ecosystems and, in particular, in internal water bodies (i.e., river, lakes, groundwater, drinking water reservoirs, recreational water utilities, and wastewater), raises concerns regarding the related impacts on environment and human health, especially in relation to the possibility of human exposure and waterborne infections. This paper reviews the current state of knowledge regarding severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) presence and persistence in human excreta, wastewaters, sewage sludge as well as in natural water bodies, and the possible implications for water services in terms of fecal transmission, public health, and workers’ risk. Furthermore, the impacts related to the adopted containment and emergency management measures on household water consumptions are also discussed, together with the potential use of wastewater-based epidemiology (WBE) assessment as a monitoring and early warning tool to be applied in case of infectious disease outbreaks. The knowledge and tools summarized in this paper provide a basic information reference supporting decisions makers in the definition of suitable measures able to pursue an efficient water and wastewater management and a reduction of health risks. Furthermore, research questions are provided in order to address technical and public health communities towards a sustainable water service management in the event of a SARS-CoV-2 re-emergence, as well as a future deadly outbreak or pandemic.

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Although most membrane bioreactors are used under aerobic conditions, over the last few years there has been increased interest in their application for anaerobic processes. This paper presents the results obtained when a bench-scale submerged anaerobic membrane bioreactor was used for the treatment of wastewaters generated in the agro-food industry. The reactor was fed with synthetic wastewater consisting of cheese whey and sucrose, and volumetric organic loading rates (OLRs) ranging from 1.5 to 13 kgCOD/(m(3)*d) were applied. Under the operating conditions studied, the maximum applicable OLR was between 6 and 10 gCOD/(g*L), which fell within the ranges of the high-rate anaerobic wastewater treatment systems, while high concentrations of volatile fatty acids were produced at higher OLR rates. With an OLR of 1.5-10 gCOD/(g*L), the reactor showed 94% COD removal, whereas this value dropped to 33% with the highest applied OLR of 13 gCOD/(g*L). The study therefore confirms that membrane bioreactors can be used for anaerobic wastewater treatment.

Mathematical modelling has been widely applied to membrane bioreactor (MBRs) processes. However, to date, very few studies have reported on the application of the anaerobic digestion model N.1 (ADM1) to anaerobic membrane processes. The aim of this study was to evaluate the applicability of the ADM1 to a submerged anaerobic MBR (SAMBR) treating simulated industrial wastewater composed of cheese whey and sucrose. This study demonstrated that the biological processes involved in SAMBRs can be modelled by using the ADM1. Moreover, the results showed that very few modifications of the parameters describing the ADM1 were required to reasonably fit the experimental data. In particular, adaptation to the specific conditions of the coefficients describing the wastewater characterisation and the reduction of the hydrolysis rate of particulate carbohydrate (khyd,ch) from 0.25 d(-1) (as suggested by the ADM1 for high-rate mesophilic reactors) to 0.13 d(-1) were required to fit the experimental data.

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This study proposes a model-based evaluation of the effect of different operating conditions with and without pre-denitrification treatment and applying three different solids retention times on the fouling mechanisms involved in membrane bioreactors (MBRs). A total of 11 fouling models obtained from literature were used to fit the transmembrane pressure variations measured in a pilot-scale MBR treating real wastewater for more than 1 year. The results showed that all the models represent reasonable descriptions of the fouling processes in the MBR tested. The model-based analysis confirmed that membrane fouling started by pore blocking (complete blocking model) and by a reduction of the pore diameter (standard blocking) while cake filtration became the dominant fouling mechanism over long-term operation. However, the different fouling mechanisms occurred almost simultaneously making it rather difficult to identify each one. The membrane "history" (i.e. age, lifespan, etc.) seems the most important factor affecting the fouling mechanism more than the applied operating conditions. Nonlinear regression of the most complex models (combined models) evaluated in this study sometimes demonstrated unreliable parameter estimates suggesting that the four basic fouling models (complete, standard, intermediate blocking and cake filtration) contain enough details to represent a reasonable description of the main fouling processes occurring in MBRs.

Application of smart meters to the residential sector can help understanding where and when water is used, thus enabling utilities to achieve an efficient management of water distribution systems. Moreover, detailed information about domestic water use can be obtained by disaggregating smart meter data collected at the household inlet point. In this paper, a rule-based, automated methodology for disaggregating household water use data into end-uses is presented. The methodology is applicable to one-minute temporal resolution data, whose granularity is slightly lower than the one generally used in other methodologies, allowing it to be potentially applied to several contexts in the field of water use monitoring. The methodology was set up and validated with data collected for two months through intrusive monitoring of four households in Bologna (Italy) and represents a pioneering case in which disaggregation performance is directly assessed by the comparison against data collected at each end-use. The results obtained showed that the methodology enables household water use to be efficiently disaggregated even if detailed information about end-use features is not available.