Wastewater Quality During the COVID-19 Pandemic – A Retrospective Analysis of a Polish Case Study

The global crisis of the Coronavirus disease-2019 (COVID-19) pandemic has caused an enormous burden not only on the health, social and economic sectors but also on many essential municipal services. Water distribution and wastewater management have faced increasing uncertainty due to the possible transmission of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) via aerosols. Additionally, behavioral and social changes have impacted the water/wastewater services and caused the need for adaptation. In this study, the presence of SARS-CoV-2 in the influent of wastewater treatment plants (WWTPs) located in Poland was analysed together with other parameters important for the water/wastewater sector, such as long-term (2015-2020) water usage and wastewater quality during the working days, and holidays, including the 2020 lockdowns. According to the obtained results, the genetic material of SARS-CoV-2 was detected in all tested wastewater samples, which confirmed the utility of wastewater monitoring to analyse the COVID-19 trends in local communities. Another important issue was the elevated presence of surfactants and the observed change in organic matter structure in raw wastewater generated during lockdowns. Also the NGS approach and 16S rRNA amplicon sequencing confirmed  the changes of functional diversity and heterogeneity in activated sludge bacterial community, especially in terms of nutrients removal and biomass separation. Thus, it is crucial to a baseline understanding of how the water-wastewater sector can serve to control disease transmission among the community and which tools should be adopted as countermeasures not only for new water consumption patterns but also for keeping safe and effective wastewater treatment.