No abstract

A new approach for estimating the household water consumption pattern was developed by taking the impact of the COVID-19 pandemic using geographical data. Water consumption data for two years before and a year after the outbreak of the pandemic were analyzed to recognize the consumption pattern on annual and bi-monthly time scales as well as in different spatial classes. Following the recognition of the pattern, the spatiotemporal distribution of household water consumption was estimated based on the discovered connections between consumption and geographical variables. Once a regression relationship between consumption and population density was observed, an idea was developed to investigate the linear equations and their coefficient of parameters in water consumption groups from very low to very high classes using the training data. The coefficients were then adjusted to account for the pandemic's impact on the consumption pattern. Results showed that the highest increases in consumption were 11% for May–July due to the impact of the pandemic while the impact was from decreasing type during lockdowns. A pandemic-induced decline in the mean of consumption was linked to temporary migration by high-income families, whereas the water consumption of others faced an increase. The impact has also increased the slope of the linear relationship between the annual water consumption and population density increased by 3.5%. The proposed model estimated the annual water consumption with the accuracy of %3.77, %1.82, and %1.85 for two years before, one year before and one year after the pandemic, respectively.

It is crucial to have access to clean water resources during the COVID-19 pandemic for hygiene, since virus infection through wastewater leaks in metropolitan areas can be a threat. Accurate monitoring of urban water resources during the pandemic seems to be the only way to confirm safe and infected resources. Here, in this study, the amount of Severe Acute Respiratory Syndrome Coronavirus 2’s Ribonucleic Acid (SARS-CoV-2 RNA) in the Tabriz urban water network located in the northwest of Iran was investigated by an extensive sampling of the city's water sources at a severe peak of the COVID-19 pandemic. The sampling process comprised a range of water sources, including wells, qanats, water treatment facilities, dams, and reservoirs. For each sample, a combination of polyethylene glycol (PEG) and sodium chloride (NaCl) was used for concentration and a laboratory RNA-based method was conducted for quantification. Before applying the extraction and quantification procedure to real samples, the proposed concentration method was verified with synthetic serum samples for the first time. After the concentration, RNA extraction was done by the BehPrep extraction column method, and Reverse Transcription Polymerase Chain Reaction (RT-PCR) detection of the virus was done by Covitech COVID-19 RT-PCR kit. In none of the water supply resources, SARS-COV-2 RNA has been detected except in a sample grabbed from a well adjacent to an urban wastewater discharge point downstream. The results of molecular analysis for the positive sample showed that the CT value and concentration of the virus genome were equal to 32.57 and 5720 copies/L, respectively. Quantitative analysis of real samples shows that the city's water network was safe at the time of the study. However, given that the positive sample was exposed to wastewater leakage, periodic sampling from wells and qanats is suggested during the pandemic until it can be proven that the leakage to these water sources is impossible.