Wastewater Loading Research Articles

Разработка имитационной модели очистных сооружений для убойного цеха птицефабрики

We designed a multi-stage technological scheme of treatment facilities for the slaughterhouse of a poultry farm in order to determine the most effective option for a changing wastewater load. The quality of purification was assessed by such physicochemical indicators as suspended solids content, dissolved oxygen concentration, biological oxygen demand, chemical oxygen demand, as well as total nitrogen and phosphorus values. The article presents the results of simulation modeling fot the behavior of the system under variable load with wastewater using the GPS-X software product with the Mantis2 calculation model. To assess the sensitivity of the model, pollutant concentrations were varied within a range of ±20% of the mean value in the original effluent. The results of modeling the operation of wastewater treatment facilities at a poultry farm were carried out when the concentration of pollutants at the entrance to the averaging tank changed from a minimum value equal to the maximum permissible concentrations to the maximum composition of wastewater from the poultry farm. It was found that, when varying the initial data, the selected scheme provides sufficiently high treatment efficiency over the entire range of changes in the concentrations of pollutants at the inlet, except for total nitrogen, which is probably due to the accumulation of organic nitrogen in activated sludge at disruption of the metabolic processes in the aeration tank. It is shown that the use of simulation modeling at the stage of development of a complex of treatment facilities allows to analyze various scenarios of system behavior, taking into account dynamic changes in the volume of water consumption during production, as well as seasonal changes in the composition of wastewater in food production.

Mathematical modeling to size anaerobic stabilization ponds intended for slaughterhouse wastewater treatment – the role of temperature and hydraulic retention time

A new mathematical model for constructing anaerobic stabilization pond treatment systems for high organic load wastewater, based on biochemical oxygen demand, temperature and hydraulic retention time, is discussed.

Valorization of Chlorella thermophila biomass cultivated in dairy wastewater for biopesticide production against bacterial rice blight: a circular biorefinery approach

Biopesticides offer a sustainable and efficient alternative to synthetic pesticides, providing a safer and more eco-friendly solution to pest management. The present work proposes an innovative approach that integrates crop protection and wastewater treatment using thermophilic microalgal strain Chlorella thermophila (CT) cultivated in nutrient-rich dairy wastewater as a growth medium. The microalgae was cultivated mixotrophically and was able to reduce both organic carbon as well as nutrient load of the dairy wastewater efficiently. The integrated circular biorefinery approach combines biomass cultivation, extraction of biopesticide compounds, and conversion to biocrude. The antimicrobial activity of the biopesticidal extracts against Xanthomonas oryzae and Pantoea agglomerans, the causative agent of bacterial rice blight, is assessed through in vitro studies. The biomass extract obtained is able to inhibit the growth of both the above-mentioned plant pathogens successfully. Mass spectroscopy analysis indicates the presence of Neophytadiene that has previously been reported for the inhibition of several pathogenic bacteria and fungi. Several other value-added products such as linoleic acid and nervonic acids were also been detected in the microalgal biomass which have extremely high nutraceutical and medicinal values. Furthermore, the study investigates the potential for co-production of biocrude from the biorefinery process via hydrothermal liquefaction. Overall, the findings of this present work represent an innovative and sustainable approach that combines wastewater treatment and crop protection using microalgal biomass.

INVESTIGATION ON PHYSICOCHEMICAL AND MICROBIOLOGICAL POLLUTION LOAD OF HUDIARA DRAIN AND ITS SUBSIDIARIES/

Majority of Industrial wastewater, both treated and untreated is being pumped into drains in Lahore; mainly converging to Hudiara drain. The same is already polluted when it enters Pakistan’s boundary by wastewater from India and as it passes through Lahore, it’s pollution levels are magnified by addition of mainly Charrar & Sattukatla Drain. In this study we performed weekly complete analysis of some Physicochemical and microbiological analysis of Hudiara drain on point of entry in Pakistan as well as the same for Charrar & Sattukatla Drains. It was observed that the organic loading of wastewater has increased 2-3 times in the last 10 years with maximum values of 1,406 and 413 mg/L obtained respectively. Major factor is the high concentration of suspended solids which ranged from 280 to 701 mg/L as well as high organic decomposition indicated by sulphides upto 23.85 mg/L. Moreover, the baseline pollution load of Hudiara Drain entering Pakistan as well as the pollution load our Industries and Adjacent canals exert directly and indirectly into Hudiara Drain.

Inferring hospital admissions from SARS-CoV-2 virus loads in wastewater in The Netherlands, August 2020 – February 2022

Wastewater-based surveillance enables tracking of SARS-CoV-2 circulation at a local scale in near-real time. Here we investigate the relation between virus loads and the number of hospital admissions in the Netherlands. Inferred virus loads from August 2020 until February 2022 in each of the 344 Dutch municipalities are analysed in a Bayesian multilevel Poisson regression to relate virus loads to daily age-stratified (in groups of 20 years) hospital admissions. Covariates include municipal vaccination coverages stratified by age and dose (first, second, and booster) and prevalence of the circulating coronavirus variants (wildtype, Alpha, Delta, and Omicron (BA.1 and BA.2)). Our model captures the relation between hospital admissions and virus loads well. Estimated hospitalisation rates per 1,000,000 persons per day at a virus load of 1013 particles range from 0.18 (95 % Prediction Interval (PI): 0.046–0.48) in children (0–19 years) to 20.1 (95 % PI: 9.46–36.8) in the oldest age group (80 years and older) in an unvaccinated population with only wildtype SARS-CoV-2 circulation. The analyses indicate a nearly twofold (1.92 (95 % PI: 1.78–2.05)) decrease in the expected number of hospitalisations at a given virus load between the Alpha and the Omicron variant. Our analyses show that virus load estimates in wastewater are closely related to the expected number of hospitalisations and provide an attractive tool to detect increased SARS-CoV-2 circulation at a local scale, even when there are few hospital admissions. Our analyses enable integration of data at the municipality level into meaningful conversion rates to translate virus loads at a local level into expected numbers of hospital admissions, which would allow for a better interpretation of virus loads detected in wastewater.

Dynamic-chance-constrained-based Fuzzy Programming Approach for Optimizing Wastewater Facultative Ponds for Multi-period Case

In this article, a novel optimization model that was specifically designed as a dynamic-chance-constrained fuzzy uncertain programming framework is introduced. This model serves the purpose of optimizing the efficiency of facultative ponds utilized in domestic wastewater treatment. The primary focus of this study was maximizing the amount of the wastewater treated in the facility subject to quality requirements via the assessment of wastewater quality through the measurement of Biological Oxygen Demand (BOD). The model's development was grounded in a real-world scenario, where decision-makers encountered uncertainties in various parameters, such as the rate of BOD degradation and the incoming wastewater load, both characterized by fuzzy membership functions. In light of this uncertainty, the decision-maker aimed to maximize the wastewater treatment capacity while maintaining a suitable safety margin for both objective and constraint functions, employing policies founded on probability and chance. A case study was carried out at the Bantul domestic wastewater treatment plant, situated in Yogyakarta, Indonesia. The study successfully identified optimal decisions regarding wastewater flow rates and processing times. As a result, it can be concluded that the proposed model effectively resolved the problem at hand, making it a valuable tool for decision-makers in similar contexts.

Building-Scale Wastewater-Based Epidemiology for SARS-CoV-2 Surveillance at Nursing Homes in A Coruña, Spain

Wastewater-based epidemiology (WBE) has become an effective tool in the surveillance of infectious diseases such as COVID-19. In this work, we performed a brief study of monitoring the SARS-CoV-2 viral load in wastewater from six nursing homes located in the metropolitan area of A Coruña (Spain) between December 2020 and March 2021. The main objective was to detect SARS-CoV-2 outbreaks among residents and study the efficacy of the vaccination campaign. SARS-CoV-2 viral load (RNA copies per L of wastewater) was determined by reverse-transcription quantitative PCR (RT-qPCR) using the quantification cycle (Cq) values for the nucleocapsid (N) gene. Our results showed that the increase in viral load preceded the increase in clinical cases, favoring an early warning system that detects COVID-19 outbreaks in advance, making it possible to contain and stop the transmission of the virus among residents. In addition, the efficacy of the new COVID-19 vaccines was evidenced, since after the vaccination campaign in nursing homes in A Coruña, it was observed that many residents did not present any symptoms of the disease, although they excreted high amounts of virus in their feces. WBE is a cost-effective strategy that should be implemented in all cities to prevent new emerging diseases or future pandemic threats.

Application of Attached Growth System for Laundry Wastewater Treatment

Laundry wastewater can be treated in a small-scale aerobic wastewater treatment (WWT) system utilizing a microbubble generator (MBG). However, removing pollutants, precisely chemical oxygen demand (COD), is often low, especially under high wastewater load conditions. This study aims to improve the WWT system’s performance by incorporating an attached growth system. The research was conducted in a small-scale WWT system with a volume of 832 L in Cokrodiningratan, Code Riverbank, Yogyakarta, treating real wastewater from a nearby laundry shop. Experiments were performed batch-wise for one week with suspended and nylon-fabric-attached growth systems. Wastewater samples from the WWT system were taken and analyzed for COD concentrations. Results indicate that the attached growth system outperforms the suspended growth system. During operation, the suspended growth system achieved a COD removal rate of approximately 78% (temperature range of 26-28°C, a pH level of 6.3-7.1, and influent COD: 377.5 mg/L). In contrast, with the introduction of attachment media under similar batch operation conditions (temperature range: 26-28°C, pH level: 6.4-7.4, influent COD: 755.5 mg/L), the COD removal efficiency increased to 94%. The incorporation of attachment media led to a notably stable performance outcome.

Characterization of inorganic and organic pollutants load in tannery wastewater: Biochemical and haematological induced changes in Swiss mice

The aim of the present study is to characterize the inorganic and organic contaminant loads in hazardous TWW and their effects on a number of biochemical and hematological changes in Swiss mice at four concentrations: C (control purified water), L(low 2.5 % TWW), M(medium 5.0 % TWW), and H(high 10 % TWW). Significant differences were observed in the chemical characteristics of TWW between the inlet and outlet of the common effluent treatment plant (CETP) in Unnao district, Uttar Pradesh, India. Physicochemical parameters such as EC, TDS, BOD, chloride, sulfate, hexavalent chromium and total nitrogen were many times higher than the Central Pollution Control Board (CPCB) limits, while other parameters such as phosphate (as P), F−, Fe, Pb, Cu, Zn, Cd and Co were within the limits. The TWW intake significantly increased Swiss mice's body weight with increasing the dose of TWW. Biochemical parameters, i.e., AST, ALT, AP, glucose, cholesterol, and triglyceride increased significantly with increasing TWW dose, whereas serum creatinine and total albumin decreased, while no specific trend was observed for urea. haematological changes indicated that hemoglobin, RBC, blood platelets, and WBC like LYM, MON, and NEU decreased significantly with an increase in TWW dose, HCT, MCV, MCH and MCHC significantly decreased.

Using detrending to assess SARS-CoV-2 wastewater loads as a leading indicator of fluctuations in COVID-19 cases at fine temporal scales: Correlations across twenty sewersheds in North Carolina

Wastewater surveillance emerged during the COVID-19 pandemic as a novel strategy for tracking the burden of illness in communities. Previous work has shown that trends in wastewater SARS-CoV-2 viral loads correlate well with reported COVID-19 case trends over longer time periods (i.e., months). We used detrending time series to reveal shorter sub-trend patterns (i.e., weeks) to identify leads or lags in the temporal alignment of the wastewater/case relationship. Daily incident COVID-19 cases and twice-weekly wastewater SARS-CoV-2 viral loads measured at 20 North Carolina sewersheds in 2021 were detrended using smoothing ranges of ∞, 16, 8, 4 and 2 weeks, to produce detrended cases and wastewater viral loads at progressively finer time scales. For each sewershed and smoothing range, we calculated the Spearman correlation between the cases and the wastewater viral loads with offsets of -7 to +7 days. We identified a conclusive lead/lag relationship at 15 of 20 sewersheds, with detrended wastewater loads temporally leading detrended COVID-19 cases at 11 of these sites. For the 11 leading sites, the correlation between wastewater loads and cases was greatest for wastewater loads sampled at a median lead time of 6 days before the cases were reported. Distinct lead/lag relationships were the most pronounced after detrending with smoothing ranges of 4–8 weeks, suggesting that SARS-CoV-2 wastewater viral loads can track fluctuations in COVID-19 case incidence rates at fine time scales and may serve as a leading indicator in many settings. These results could help public health officials identify, and deploy timely responses in, areas where cases are increasing faster than the overall pandemic trend.

Zooming in to the neighborhood level: A year-long wastewater-based epidemiology monitoring campaign for COVID-19 in small intraurban catchments

In recent years, wastewater-based epidemiology (WBE) has emerged as a valuable and cost-effective tool for monitoring the prevalence of COVID-19. Large-scale monitoring efforts have been implemented in numerous countries, primarily focusing on sampling at the entrance of wastewater treatment plants (WWTPs) to cover a large population. However, sampling at a finer spatial scale, such as at the neighborhood level (NGBs), pose new challenges, including the absence of composite sampling infrastructure and increased uncertainty due to the dynamics of small catchments. This study aims to investigate the feasibility and accuracy of WBE when deployed at the neighborhood level (sampling in sewers) compared to the city level (sampling at the entrance of a WWTP). To achieve this, we deployed specific WBE sampling stations at the intraurban scale within three NGBs in Barcelona, Spain. The study period covers the 5th and the 6th waves of COVID-19 in Spain, spanning from March 2021 to March 2022, along with the WWTP downstream from the NGBs. The results showed a strong correlation between the dynamics of COVID-19 clinical cases and wastewater SARS-CoV-2 loads at both the NGB and city levels. Notably, during the 5th wave, which was dominated by the Delta SARS-CoV-2 variant, wastewater loads were higher than during the 6th wave (Omicron variant), despite a lower number of clinical cases recorded during the 5th wave. The correlations between wastewater loads and clinical cases at the NGB level were stronger than at the WWTP level. However, the early warning potential varied across neighborhoods and waves, with some cases showing a one-week early warning and others lacking any significant early warning signal. Interestingly, the prevalence of COVID-19 did not exhibit major differences among NGBs with different socioeconomic statuses.

Data-driven systematic analysis of waterborne viruses and health risks during the wastewater reclamation process

Waterborne viral epidemics are a major threat to public health. Increasing interest in wastewater reclamation highlights the importance of understanding the health risks associated with potential microbial hazards, particularly for reused water in direct contact with humans. This study focused on identifying viral epidemic patterns in municipal wastewater reused for recreational applications based on long-term, spatially explicit global literature data during 2000–2021, and modelled human health risks from multiple exposure pathways using a well-established quantitative microbial risk assessment methodology. Global median viral loads in municipal wastewater ranged from 7.92 × 104 to 1.4 × 106 GC L−1 in the following ascending order: human adenovirus (HAdV), norovirus (NoV) GII, enterovirus (EV), NoV GI, rotavirus (RV), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Following secondary or tertiary wastewater treatment, NoV GI, NoV GII, EV, and RV showed a relatively higher and more stable log reduction value with medians all above 0.8 (84%), whereas SARS-CoV-2 and HAdV showed a relatively lower reduction, with medians ranging from 0.33 (53%) to 0.55 (72%). A subsequent disinfection process effectively enhanced viral removal to over 0.89-log (87%). The predicted event probability of virus-related gastrointestinal illness and acute febrile respiratory illnesses in reclaimed recreational water exceeded the World Health Organization recommended recreational risk benchmark (5% and 1.9%, respectively). Overall, our results provided insights on health risks associated with reusing wastewater for recreational purposes and highlighted the need for establishing a regulatory framework ensuring the safety management of reclaimed waters.

Water pollution remediation in Kazakhstan: evaluating bacterial consortiums for organic pollutant decomposition

Abstract Wastewater treatment is one of the key problems that has to be solved by environmental biotechnology. Wastewater bioremediation is one of the most efficient and safest methods to replenish water resources. The aim of this study is to investigate the potential of using bacterial consortiums for reducing the organic load in wastewater, specifically focusing on water samples collected from three water bodies in central and northern Kazakhstan, which are known for their high levels of organic pollution. This study utilized bacterial strains from a microorganism collection to create consortiums. These consortiums were used to treat wastewater from polluted water bodies in Kazakhstan, focusing on parameters like COD, BOD5, ammonia, and phosphate. The methodology involved culturing strains, collecting water samples, and analyzing various parameters. Statistical analysis was performed to assess the results. The study found that two bacterial consortiums, 7BLB and 7BLPA, were the most effective in reducing COD, ammonia, and ammonia nitrogen in wastewater. The consortium 6BLP was highly effective at reducing phosphate levels, surpassing acceptable standards. Hydrogen levels met regulatory requirements in all cases. The study recommends further investigation of these consortiums’ impact on other water quality indicators and suggests conducting field experiments in natural water ponds.

Trends in SARS-CoV-2 clinically confirmed cases and viral load in wastewater: A critical alignment for Padua city (NE Italy)

Since the beginning of the COVID-19 pandemic, wastewater-based epidemiology (WBE) has been depicted as a promising environmental surveillance tool and early warning system. Predictive models for the estimate of COVID-19 cases from wastewater viral loads also earned lot of interest and are currently under development. Hereby a pilot study that compares WBE surveillance data with confirmed cases, total hospitalizations, doses of vaccine administered and predominance of coronavirus variants.Composite 24hrs wastewater samples were collected weekly between September 2021 and July 2022 from Padua wastewater treatment plant. Samples were processed following a previously published method. One-step RT-qPCR was performed for quantification, adapting an Orf1b-nsp14 gene assay. Variant replacement was derived from the monthly bulletins of the Italian National Health Institute. Aggregate data on vaccine doses administered and on COVID-19 prevalence and hospitalizations were retrieved from official reports.Eighty-two samples were processed. Viral loads highlighted 3 major peaks in January, April and July 2022. Quantitation of SARS-CoV-2 in wastewater and clinical surveillance resulted temporally juxtaposable. However, variation of the two curves is not proportional. SARS-CoV-2 showed its highest peak in April, whereas maximum COVID-19 prevalence was achieved in January. Total hospitalizations followed the prevalence trend. Omicron BA.1 started to replace the Delta variant in December 2021. Subsequently, the shift towards Omicron BA.2 occurred between February and April 2022. Finally, BA.4/5 attested around June, somehow preceding the summer peak.Emergence of Omicron BA.1 over Delta could be a possible driver of the increase in both clinical cases and wastewater viral load in January 2022. In late March 2022, Omicron BA.2 replaced BA.1: this reflected in a steep increase of wastewater viral load, but not of COVID-19 confirmed cases. When a dramatic drop in the testing capacity of clinical surveillance occurred, WBE was possibly capable of detecting a substantial increase in viral circulation.

Wastewater-based Epidemiology and SARS-CoV-2: Variant Trends in the Apulia Region (Southern Italy) and Effect of Some Environmental Parameters

During the COVID-19 pandemic, wastewater monitoring has been used to monitor the levels of SARS-CoV-2 RNA entering the sewerage system. In Italy, the Istituto Superiore di Sanità coordinated the SARI project (Sorveglianza Ambientale Reflue in Italia) to detect SARS-CoV-2 and its variants. In this study, the concentration of SARS-CoV-2 and its variants in raw wastewater against COVID-19 cases was evaluated together with the effect of temperature and precipitation on virus spread. We validated a predictive model, proposed by De Giglio et al., 2021, to establish the number of COVID-19 cases/100,000 inhabitants. A receiver operating characteristic curve model was applied to predict the number of COVID-19 cases and Poisson regression was applied to study the effect of temperature and rainfall on viral load. In Apulia, from October 2021 to December 2022, we analyzed 1041 samples, of which 985 (94.6%) tested positive for SARS-CoV-2. Median atmospheric temperature was inversely proportional to viral load in wastewater; no correlation was found with precipitation. The predictive model confirmed that at least 11 cases/100,000 inhabitants would occur in the 15 days following the detection of the virus in wastewater. Environmental surveillance of SARS-CoV-2 can be used to map the virus and its variants.

Optimization of wastewater treatment systems for growing industrial parks

Wastewater treatment is one of the crucial functions of industrial parks as wastewater from industrial facilities usually contains toxic compounds that can cause damage to the environment. To control their environmental loads, industrial parks make investment decisions for wastewater treatment plants. For this, they need to consider technical and economic factors as well as future growth projections as substantial construction and operational costs of wastewater treatment plants have to be shared by all companies in an industrial park. In this paper, we consider the long-term capacity planning problem for wastewater treatment facilities of a stochastically growing industrial park. By explicitly modeling randomness in the arrival of new tenants and their random wastewater discharges, our model calculates the future mean and variance of wastewater flow in the industrial park. Mean and variance are used in a Mixed Integer Programming Model to optimize wastewater treatment plant selection over a long planning horizon (30 years). By fitting our first model to empirical data from an industrial park in Turkey, we find that considering the variance of wastewater load is critical for long-term planning. Also, we quantify the economic significance of lowering wastewater discharges which can be achieved by water recycling or interplant water exchange.

Bulk industrial production of sustainable cellulosic printing fabric using agricultural waste to reduce the impact of climate change

In this research paper, a novel process was developed for reactive printing of cotton fabric, with the objective of producing a high-quality printed fabric that is sustainable, eco-friendly, and low-cost which will ultimately reduce the impact of climate change. The study incorporated substituted tamarind polysaccharide (STP) obtained from agricultural waste, trichloro-ethanoic acid (TCEA), and polyethylene glycol (PEG-400) in the reactive printing paste. Tamarind starch was extracted from the seeds having 72 % yield, and substitution was performed to use it as a thickener in the printing paste. The conventional printing system was formulated with sodium alginate, urea, and sodium bicarbonate at dose levels of 2 %, 15 %, and 2.5 %, respectively, while the modified recipe was formulated with STP and TCEA at 5 % and 3 % dose levels, respectively along with varying doses of PEG-400 (0 %, 1 %, and 2 %) in novel prints. Various factors such as shade comparison, penetration, staining on the white ground, washing, rubbing, light and perspiration fastness, sharpness of edges, and fabric hardness were evaluated for all the recipes. The study demonstrated that the optimal outcomes were obtained with a 2 % PEG-400 dose level. This study represents a significant contribution to sustainable textile production, as tamarind agriculture waste was used as a raw material, which is an environmentally friendly alternative of sodium alginate that reduces the wastewater load. Additionally, PEG-400 was utilized as a nitrogen-free solubilizing moisture management substitution of urea for printing, while TCEA dissociated at high temperature to make alkaline pH during curing of the printed fabric to replace sodium bicarbonate. This research is a novel contribution to the printing industry, as these three constituents have not been previously used together other than this research group, in the history of reactive printing.

Reduction of pollution loads based on sewage treatment projects around a lake: A case study on Erhai Lake.

Erhai Lake is a highland freshwater lake in Dali, China. Rapid tourism development has generated large amounts of pollutants. Since 2015, six wastewater treatment plants (WWTPs) have been built to treat wastewater collected through sewage interception projects. In this study, reductions in the pollution load of wastewater from different sources were evaluated by considering the effects of groundwater leakage, microbial degradation, and rainfall-runoff. The results showed that the systems reduced the chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP) loads by 85, 83, and 85%, respectively. Discharge wastewater has the characteristics of a low concentration of domestic sewage discharge, large tourist sewage discharge, and high concentration of livestock wastewater. Due to the high groundwater level, there is groundwater infiltration in the influent water of WWTPs, which dilutes the pollutant concentration of the influent and, therefore, results in a lower treatment efficiency. Further treatment of tailwater also reduced the pollution loads discharged into the lake as well as the COD and TN by 10.25 and 22.90%, respectively. The results indicate that groundwater infiltration in the sewer network system is the primary target to be addressed in future developments.

Recycled clay bricks and palm kernel shell as constructed wetland substrate for wastewater treatment: An engineered closed circuit circular economy approach

Wastewater treatment using green technologies contributes significantly to a circular economy. Constructed wetlands (CW) using green substrates or recycled materials are low-cost cleaner technologies that further contribute to a closed circuit. This study assessed the performance of two recycled materials, Waste Clay Brick (WCB) and Palm Kernel Shells (PKS), as suitable substrates in a CW for wastewater treatment. Five (5) horizontal subsurface flow constructed wetlands (HSSF CW), designed and fabricated using galvanized steel, were set up for the treatment of domestic wastewater (sewage). The wetland cells were packed with small (WCBS, PKSS) or large (WCBL or PKSL) particle size substrates with one cell using sand as control. The CW operated under two hydraulic loading rates (HLR), 50l/d (HLR-1) and 80l/d (HLR-2). Overall, the effluent quality of HLR-1 was relatively better than HLR-2. pH and turbidity of effluent were satisfactory and within the Ghana Environmental Protection Agency (EPA) guidelines for discharge of wastewater into surface water bodies. For both hydraulic loading rates, the highest removal efficiencies of BOD5 (73.97%), COD (71.89%), TSS (90.82%), TP (71.13%), TN (49.41%) were recorded for WCB. Coliform removal was highest in the Palm Kernel Shell (98.6%), followed by the control (97.39%). Wastewater treatment efficiency decreased with increasing wastewater loading rates for all parameters in Waste Clay Brick and BOD5 and TP in Palm Kernel Shell. WCB demonstrated superior treatment potential compared to PKS for all parameters except coliform removal.

Understanding the efficacy of wastewater surveillance for SARS-CoV-2 in two diverse communities.

During the COVID-19 pandemic, wastewater-based surveillance has been shown to be a useful tool for monitoring the spread of disease in communities and the emergence of new viral variants of concern. As the pandemic enters its fourth year and clinical testing has declined, wastewater offers a consistent non-intrusive way to monitor community health in the long term. This study sought to understand how accurately wastewater monitoring represented the actual burden of disease between communities. Two communities varying in size and demographics in Michigan were monitored for SARS-CoV-2 in wastewater between March of 2020 and February of 2022. Additionally, each community was monitored for SARS-CoV-2 variants of concern from December 2020 to February 2022. Wastewater results were compared with zipcode and county level COVID-19 case data to determine which scope of clinical surveillance was most correlated with wastewater loading. Pearson r correlations were highest in the smaller of the two communities (population of 25,000) for N1 GC/person/day with zipcode level case data, and date of the onset of symptoms (r = 0.81). A clear difference was seen with more cases and virus signals in the wastewater of the larger community (population 110,000) when examined based on vaccine status, which reached only 50%. While wastewater levels of SARS-CoV-2 had a lower correlation to cases in the larger community, the information was still seen as valuable in supporting public health actions and further data including vaccination status should be examined in the future.