Wastewater Collection Systems Research Articles

HydroFATE (v1): a high-resolution contaminant fate model for the global river system

Abstract. Pharmaceuticals and household chemicals are neither fully consumed nor fully metabolized when routinely used by humans, thereby resulting in the emission of residues down household drains and into wastewater collection systems. Since treatment systems cannot entirely remove these substances from wastewaters, the contaminants from many households connected to sewer systems are continually released into surface waters. Furthermore, diffuse contributions of wastewaters from populations that are not connected to treatment systems can directly (i.e., through surface runoff) or indirectly (i.e., through soils and groundwater) contribute to contaminant concentrations in rivers and lakes. The unplanned and unmonitored release of such contaminants can pose important risks to aquatic ecosystems and ultimately human health. In this work, the contaminant fate model HydroFATE is presented, which is designed to estimate the surface-water concentrations of domestically used substances for virtually any river in the world. The emission of compounds is calculated based on per capita consumption rates and population density. A global database of wastewater treatment plants is used to separate the effluent pathways from populations into treated and untreated and to incorporate the contaminant pathways into the river network. The transport in the river system is simulated while accounting for processes of environmental decay in streams and in lakes. To serve as a preliminary performance evaluation and proof of concept of the model, the antibiotic sulfamethoxazole (SMX) was chosen, due to its widespread use and the availability of input and validation data. The comparison of modelled concentrations against a compilation of reported SMX measurements in surface waters revealed reasonable results despite inherent model uncertainties. A total of 409 000 km of rivers were predicted to have SMX concentrations that exceed environmental risk thresholds. Given the high spatial resolution of predictions, HydroFATE is particularly useful as a screening tool to identify areas of potentially elevated contaminant exposure and to guide where local monitoring and mitigation strategies should be prioritized.

An efficient wastewater collection model for groundwater resource protection in smart cities

Efficient wastewater collection is a critical concern in the development of smart cities, where sustainable urban infrastructure is paramount. In the context of smart city wastewater optimization, this study highlights the need for a comprehensive approach that considers both surface water and groundwater dynamics. Existing methods often fall short in addressing groundwater-related concerns, with limitations in accounting for potential contamination and aquifer vulnerability. The proposed method integrates a nuanced understanding of groundwater aspects, providing a more robust and sustainable solution for urban water resource management. This research introduces a new approach that harnesses the power of Divide-And-Conquer (DAC) and Variable Neighborhood Search (VNS) to optimize wastewater collection systems in smart cities. The DAC strategy divides the city into manageable zones, simplifying the optimization problem for parallel processing in large-scale urban environments. VNS fine-tunes wastewater collection networks within each zone by exploring diverse neighborhood solutions. The DAC and VNS offers several benefits, including improved efficiency in wastewater transport, reduced energy consumption, and minimized environmental impact. Zoning the urban landscape is a strategic approach to optimize wastewater collection in smart cities. It involves dividing the city into manageable zones based on specific criteria such as geographical features, population density, and infrastructure layout. Each zone is treated as an independent unit for focused analysis and optimization. The optimization process employs a scoring function that combines weighted criteria, yielding a composite score for each geographical location. Applying a threshold or clustering algorithm group's locations into zones, facilitating tailored wastewater management strategies. By optimizing collection routes and infrastructure design, this approach assists smart cities in achieving sustainability goals while efficiently managing wastewater. The study showcases the potential of DAC and VNS as a robust and adaptable solution for wastewater collection in smart cities, contributing to the development of greener, more resource-efficient urban areas.

Wastewater Management in Tomato Factories

Tomato (Lycopersicon esculentum) is a globally consumed vegetable with a significant role in the food industry. In 2021, global tomato production exceeded 189.1 million metric tons, emphasizing its economic importance. This research delves into the challenges posed by wastewater generated during tomato processing and explores sustainable strategies for managing it. Case studies were conducted in tomato processing plants in California, Kadawa (Kura LGA, Kano State), and Kumo (Gombe State) to assess their wastewater management practices. The findings revealed a lack of uniform wastewater collection systems in the studied factories, highlighting the need for improved environmental sustainability. As Bauchi State's population and industrialization grow, addressing the wastewater issue becomes increasingly urgent. Inadequate wastewater management can have detrimental effects on human health, water supplies, and the environment. To mitigate these challenges, this study proposes the integration of sustainable techniques in tomato processing factories. The objectives include quantifying wastewater generation, designing a functional factory layout applicable to other food processing industries, and creating a factory design that promotes sustainable water use. Site selection criteria were established, focusing on accessibility, labor availability, utilities, expansion potential, topography, and environmental impact. After a thorough evaluation, a site in Hardawa, Misau Local Government Area of Bauchi State, was identified as the most suitable location for the proposed tomato processing factory. The factory's design brief includes provisions for production facilities, administrative blocks, and worker facilities. Space requirements were determined based on the anticipated activities within each section. The proposed design emphasizes water harvesting and recycling to reduce wastewater generation and promote sustainability. In conclusion, this research underscores the importance of addressing wastewater management in tomato processing factories. By implementing sustainable design principles, factories can minimize environmental impact, enhance operational efficiency, and demonstrate commitment to ethical business practices. The proposed design offers a comprehensive solution to the wastewater challenge, ensuring compliance with environmental standards and safeguarding natural resources. Recommendations include collaboration between factory management and government authorities, the adoption of sustainable design approaches in future tomato processing facilities, and the allocation of resources for ongoing maintenance. Embracing these recommendations will contribute to more responsible and environmentally conscious tomato processing practices.

Ozone micron bubble pretreatment for antibiotic resistance genes reduction in hospital wastewater treatment

Ozone micron bubble (OMB) treatment offers a promising approach to effectively eliminate Antibiotic Resistance Genes (ARGs) from infectious medical wastewater and mitigate the threat of drug resistance transmission. This study evaluated the effectiveness of OMB treatment for reducing ARGs from infectious medical wastewater in laboratory and on-site pilot treatment setups. In part, the presence of antibiotic residues in a hospital wastewater treatment plant (WWTP) and the impact of hospital wastewater on the distribution of ARGs in a wastewater collection system were also investigated. The results of wastewater collection system survey revealed a high prevalence of ARGs in the system, particularly mcr-1, largely originating from medical wastewater discharges. Furthermore, analysis of antibiotic residues in the hospital wastewater treatment system showed significant accumulation, particularly of quinolone antibiotics, in the biomass of the biological oxidation tank, suggesting a potential risk of ARG proliferation within the system. Comparison of wastewater samples from domestic and hospital WWTPs revealed a relatively higher abundance of ARGs in the latter, with differences ranging from 2.2 to sixfold between corresponding locations in the treatment plants. Notably, the biological oxidation unit of both WWTPs exhibited a greater proportion of ARGs among all sampled points, indicating the potential proliferation of ARGs within the biomass of the treatment units. ARG degradation experiments showed that OMB treatment resulted in a significantly lower CT value (9.3 mg O3 L−1 min) compared to ozone coarse bubble treatment (102 mg O3 L−1 min) under identical test conditions. Moreover, the use of OMB on site significantly reduced the accumulation of ARGs in hospital wastewater, underscoring its potential as an effective solution for mitigating ARG spread.

Occurrence, fate, and ecological risk assessment of bisphenol A, butylparaben, and diethyl‐phthalate in collection systems and the wastewater treatment plant of the urban area

AbstractIn the present work, wastewater treatment plants and collection systems from Nagpur, Central India were studied for frequently occurring endocrine disrupting chemicals. All the EDCs, such as bisphenol A, butylparaben, and diethyl phthalate were present in all the collected samples with a detection frequency of 100%. Laboratory analysis revealed high bisphenol A, butylparaben, and diethyl phthalate levels, with mean concentrations of 79.10, 4.12, and 2.25 μg/L, respectively, in influent samples and 33.20, 1.62, and 0.77 μg/L, respectively, in the effluent wastewater. The distribution of the emergent pollutants among the sampling locations was found to be consistent with the physicochemical characteristics of wastewater, according to the component analysis, and the sites with the highest levels of contamination were also identified. Finally, an ecological risk assessment was carried out for aquatic biota in terms of risk quotients. The risk quotients for the target chemicals in effluent wastewater suggested a minimal impact, except for the target insect Chrironomus riparius, which had a risk quotient value of 33.20 for bisphenol A.

Identifikasi dan Penentuan Strategi Pengelolaan Limbah Domestik Pada Kawasan Pesisir Dusun Kisik, Kabupaten Pasuruan

In Indonesia, around 60% of the total 250 million population lives in coastal areas. Kisik Hamlet is one of the settlements located in the coastal area of the Madura Strait and is a densely populated settlement. The increase in population in coastal areas is vulnerable to increasing problems with the quality of the surrounding waters because people still consider rivers, seas, and beaches as places for dumping solid and liquid waste. In this research, we studied and assessed community perceptions regarding the level of awareness and desire to participate in managing domestic wastewater as an initial idea of whether ongoing research will be conducted regarding wastewater processing facilities in this area. The methods used are observation and interviews, questionnaires, and data analysis with SPSS software. The research results show that the majority of people still dispose of gray water through drainage and directly into the sea, and only a small percentage dispose of black water into septic tanks. However, the level of awareness and desire to participate by the community in waste management efforts is quite high. Therefore, it is necessary to implement a waste management strategy by building a community-based domestic wastewater collection system (Communal IPAL), accompanied by ongoing outreach and education to support the successful implementation and evaluation of this strategy.

EXTREME RAINFALL-RUNOFF MODELING DURING REMNANTS OF IDA IN NEW YORK

While the effects of wind and pressure on coastal waters can generate large storm surges that lead to coastal flooding, storm surge represents only one driver of flooding. In reality, flooding is often driven by the combined action of several geophysical drivers (Couasnon et al., 2020; Zscheischler et al., 2018). Formally compound flooding is defined as the combined action of meteorological forces, tidal forces,, fluvial, and pluvial discharge (Zscheischler et al., 2018). Recent events such as the extreme rainfall associated with the remnants of Hurricane Ida in the Northeast United States have demonstrated the need to model the rainfall-runoff impact (i.e., pluvial flooding) and its downstream impact (i.e., fluvial flooding). In extreme rainfall cases in which large quantities of precipitation fall in short periods, urban environments often flood, and wastewater collection systems often exceed their design limit. In severe scenarios, surcharged sewer systems can significantly exacerbate urban flooding. While several existing flood risk methods consider storm surge in them approach, it remains active research topic concerning how and when rainfall-runoff processes should be incorporated in flooding models to assess site-specific flood risk. Often an approach is pursued that involves loosely coupling multiple numerical models each modeling a particular flood driver; however, this approach can become cumbersome. Instead in this work we pursue a different approach in which compound flooding can be resolved in a single numerical model (herein termed a monolithic approach).

Status of Research on Greenhouse Gas Emissions from Wastewater Collection Systems

Wastewater collection systems (WCSs) not only play an indispensable role in urban life but also significantly contribute to greenhouse gas (GHG) emissions. Based on extensive literature research, this study (1) summarizes current research on the production mechanisms, influencing factors, control techniques, and quantitative estimates of GHGs emitted from WCSs and (2) presents initial estimates of total GHG emissions from WCSs in China. A variety of factors affect GHG production, but standard methods are still lacking to quantify GHG emissions from WCSs. China’s WCSs emit approximately 3.86–15.35 Mt of CO2eq annually (equivalent to 5.1–20.2% of the GHG emissions from wastewater treatment). Thus, GHG emissions from WCSs are significant and deserve attention. Control of GHGs in WCSs can be achieved through the application of chemical agents, while the construction of a green stormwater infrastructure can further facilitate GHG reductions. This review provides valuable insights for policymakers to consider in future policy planning related to GHG reduction and the improved operation of WCSs. Future research should focus on quantifying the impacts of various factors and accumulating field data on GHGs in various regions to facilitate the development of standardized calculation methods.

Age-dependent failure probabilities of corroding concrete sewer pipes under traffic loads

Concrete pipes are frequently used in the wastewater infrastructure. These buried structures are prone to ageing and deterioration, as well as damage under excessive stresses from traffic. This study presents the first set of temporal fragility models for underground concrete sewer pipes under the compounding effects of corrosion and truck loads. To address the high computational costs of fragility modeling, Bayesian Additive Regression Trees (BART) – a machine-learning based meta-model – are trained using a high-fidelity computational model of buried concrete pipes. The BART models are subsequently applied to develop age-dependent fragility models for serviceability and collapse of pipes conditional on truck loads. Considered uncertainties include statistically significant concrete and soil properties, truck load, and environmental factors that affect the corrosion of concrete sewer pipes. Results indicate that the direction of traffic stream, the degree of loss of wall thickness due to corrosion, and the maximum allowed truck load are critical factors that must be considered when planning inspection, rehabilitation, and retrofit of this underground infrastructure. According to the results, concrete sewer pipes buried in perpendicular to the direction of traffic flow are more vulnerable than those that are parallel to the direction of traffic flow. The results highlight that the probability of collapse is insignificant when it comes to vehicles weighing less than the design truck weight; however, the probability of collapse significantly increases for the moderate and severe corroded sewer pipes when it comes to the overweight vehicles. The age-dependent fragility models indicate that for sewer pipes buried perpendicular to the direction of traffic stream with service life of less than 25 years, the probability of the first major structural defect is less than 5%. This is also true for sewer pipes that have been in service for less than 45 years if the traffic stream is parallel to the buried pipe. The developed fragility models also constitute a key component of quantitative risk assessment of underground wastewater collection systems.

Distribution and ecological risk of polycyclic aromatic hydrocarbons in wastewater treatment plant sludge and sewer sediment from cities in Middle and Lower Yangtze River

The objective of this study was to conduct a comparative study of the distribution and ecological risk of polycyclic aromatic hydrocarbons (PAHs) in the sewage collection and treatment system of four cities located in the middle and lower reaches of the Yangtze River. The results revealed that the mean concentration of 16 ΣPAHs was higher in the sewer sediments (1489.45 ng·g−1) than in the sewage sludge (781.78 ng·g−1). PAH monomers were detected in all cases, with higher mean Pyr, Chr, BbF and BaP concentrations. PAHs with 4–6 rings were dominant in both sewage sludge and sewer sediment monomer PAHs. With the isomer ratio method and positive definite matrix factor (PMF) method, the results showed that the major sources of PAHs in sewage sludge were petroleum sources, coal tar, and coking activities, whereas PAHs in sewer sediments were primarily from wood combustion, automobile emissions, and diesel engine emissions. Of all the PAH monomers, BaP and DahA had the highest toxic equivalents, although their levels were not the highest. Based on the assessment of ΣPAHs, it was concluded that both sewage sludge and sewer sediments had medium ecological risk. The results of this study provide reference information for the control of PAHs in the wastewater collection and treatment system of the middle and lower reaches of the Yangtze River.

Upgrading water supply and wastewater collection systems in rural areas as a way to improve quality of life of the population of Russia

This article pinpoints the problem of no modern water supply and sewage systems in homes of ca. 22-24 million people in the Russian Federation residing in the countryside nowadays. As a statistical database, the authors use the results of the Rosstat surveys entitled "The Comprehensive monitoring of the living conditions of the population" that were conducted in 2011 and 2020. We analyze the data on cold and hot water supply systems, sewage systems and toilets in homes of households across the country in general, in rural areas and in individual houses (the private sector). The article reveals that there are no modern types of sewage systems in homes of almost two-thirds of households, whereas modern toilet is not installed in one-third, hot water supply — in 26 per cent, and cold water supply system — in homes of 11 per cent of households in rural areas. When considering individual houses in rural settlements the situation is even worse, and the numbers reach 81 per cent, 42 per cent, 30 per cent and 13 per cent respectively. Six groups of regions of the Russian Federation are distinguished by the share of households that do not have access to any water supply system in their homes. Subsequently, we define four reasons why rural areas have been consistently lagging behind cities and towns in terms of infrastructural development, including the decline of local Soviet-era agricultural enterprises (kolkhozes and sovkhozes) in the beginning of the 1990s and the development of rural territories as a generally low priority topic for the Federal executive bodies. The other two reasons are the virtual disconnection of rural territories from the state policies in the area of housing construction and utilities and the insufficient compatibility of the current model of providing state and municipal services to the population living mostly in individual houses on private land under the conditions of shortage of financial resources. In conclusion, we propose a set of measures aimed at boosting resolution of the ongoing problems with universal access to modern water supply and sewage systems in rural areas of the Russian Federation.

Methane Emissions from Municipal Wastewater Collection and Treatment Systems.

Municipal wastewater collection and treatment systems are critical infrastructures, and they are also identified as major sources of anthropogenic CH4 emissions that contribute to climate change. The actual CH4 emissions at the plant- or regional level vary greatly due to site-specific conditions as well as high seasonal and diurnal variations. Here, we conducted the first quantitative analysis of CH4 emissions from different types of sewers and water resource recovery facilities (WRRFs). We examined variations in CH4 emissions associated with methods applied in different monitoring campaigns, and identified main CH4 sources and sinks to facilitate carbon emission reduction efforts in the wastewater sector. We found plant-wide CH4 emissions vary by orders of magnitude, from 0.01 to 110 g CH4/m3 with high emissions associated with plants equipped with anaerobic digestion or stabilization ponds. Rising mains show higher dissolved CH4 concentrations than gravity sewers when transporting similar raw sewage under similar environmental conditions, but the latter dominates most collection systems around the world. Using the updated data sets, we estimated annual CH4 emission from the U.S. centralized, municipal wastewater treatment to be approximately 10.9 ± 7.0 MMT CO2-eq/year, which is about twice as the IPCC (2019) Tier 2 estimates (4.3-6.1 MMT CO2-eq/year). Given CH4 emission control will play a crucial role in achieving net zero carbon goals by the midcentury, more studies are needed to profile and mitigate CH4 emissions from the wastewater sector.

Block Chain Scada Quality Control for in Industrial Automation

Abstract: Scada systems are highly distributed systems used to control geographically dispersed assets, often scattered over thousands of square kilometers, where centralized data acquisition and control are critical to system operation. They are used in distribution systems such as water distribution and waste water collection systems, oil and gas pipelines, electrical power grids, and railway transportation systems. A scada control center performs centralized monitoring and control for field sites over longdistance communications networks, including monitoring alarms and processing status data. Based on information received from remote stations, automated or opera tor-driven supervisory commands can be pushed to remote station control devices, which are often referred to as field devices . Field devices control local operations such as opening and closing valves and breakers, collecting data from sensor systems, and monitoring the local environment for alarm conditions. In general, the error rate of 1-1.5 percent found in manual working can be brought down to 0.00001 percent with automation. as stakeholders have begun to increasingly demand certain quality standards, automation has also become a key part of today’s manufacturing setup.” automation is the key in all types of manufacturing, especially in the face of an emerging global economy. From being used to increase productivity and reduce cost, automation has now become vital to increasing product quality. Further, in certain fields like semiconductor chip manufacturing where miniaturization is the key, machines are capable of achieving greater precision and speed than humans-after all.

Use of Shredded Recycled Plastic as Filter Bed Packing in a Vertical Flow Filter for Onsite Wastewater Treatment Plants: Preliminary Findings

Household wastewater is a problem, especially in areas with a dispersed settlement where there is no wastewater collection system or wastewater treatment plant. In this case, it is necessary to build a local or onsite wastewater treatment plant. This paper is an attempt to analyse the possibility of using recycled shredded ABS plastic (acrylonitrile butadiene styrene) as packing media in an experimental vertical flow filter for use in on-site wastewater treatment plants. Studies have shown that shredded recycled ABS is a promising filtration material that has several features important in the treatment process, like a large surface area, high mechanical strength and chemical inertness. The system was operated with a hydraulic load of 50 dm3/m2 (3 months). BOD5 (biochemical oxygen demand), COD (chemical oxygen demand), and total suspended solids (TSS) reduction efficiency in the primary effluent was high; 94.4%, 77.8%, and 92.8%, respectively.

Batch correction methods for nontarget chemical analysis data: application to a municipal wastewater collection system

Nontarget chemical analysis using high-resolution mass spectrometry has increasingly been used to discern spatial patterns and temporal trends in anthropogenic chemical abundance in natural and engineered systems. A critical experimental design consideration in such applications, especially those monitoring complex matrices over long time periods, is a choice between analyzing samples in multiple batches as they are collected, or in one batch after all samples have been processed. While datasets acquired in multiple analytical batches can include the effects of instrumental variability over time, datasets acquired in a single batch risk compound degradation during sample storage. To assess the influence of batch effects on the analysis and interpretation of nontarget data, this study examined a set of 56 samples collected from a municipal wastewater system over 7 months. Each month’s samples included 6 from sites within the collection system, one combined influent, and one treated effluent sample. Samples were analyzed using liquid chromatography high-resolution mass spectrometry in positive electrospray ionization mode in multiple batches as the samples were collected and in a single batch at the conclusion of the study. Data were aligned and normalized using internal standard scaling and ComBat, an empirical Bayes method developed for estimating and removing batch effects in microarrays. As judged by multiple lines of evidence, including comparing principal variance component analysis between single and multi-batch datasets and through patterns in principal components and hierarchical clustering analyses, ComBat appeared to significantly reduce the influence of batch effects. For this reason, we recommend the use of more, small batches with an appropriate batch correction step rather than acquisition in one large batch.Graphical abstract

An Integrated Simulation-Optimization Approach for Dynamic Design of the Urban Wastewater Collection Systems

In this study, a simulation-optimization approach is proposed for dynamic design of the urban wastewater collection systems. The proposed approach consists of the mutual integration of the Storm Water Management Model (SWMM), developed by the U.S. Environmental Protection Agency (US-EPA) and the heuristic Harmony Search (HS) optimization approach. Unlike the previous approaches developed to solve wastewater collection system design problems, the proposed approach simulates the hydraulic flow process by considering unsteady state flow conditions based on the dynamic wave model. The objective of the HS-based optimization model is to determine the pipe slopes so that the total system cost is minimized. After determining the pipe slopes, the corresponding pipe diameters were determined by developing an internal solution approach. All the physical and managerial constraints that should be considered during the search process have been considered by means of the penalty function approach. The applicability of the proposed approach was evaluated by solving two example problems. Identified results indicated that the proposed approach can effectively solve the dynamic design problems of the wastewater collection systems.

Natural resource management in the engineering protection of puppet theater structures from external impacts

The paper considers the management of natural resources with their negative impact on the public building structure. Recommendations for the engineering protection of the object under consideration from atmospheric precipitation that damages the building structure have been developed. The paper considers the test report of the load-bearing structures of the puppet theater building. Based on the performed surveys of the technical condition, it was found that the operational safety and durability of the building structure do not meet the current regulatory documents requirements. Based on the instrumental survey of the load-bearing structure of the building, conclusions about the required conditions for ensuring the safety of operation were made. Also the proposals for the further normal operation of the building were made. Measures to improve the technical condition of the tested elements of building structures have been developed. The following is recommended: to ensure the fulfillment of technical conditions for water-bearing communications; make a waterproof coating of sidewalks; maintain the required temperature and humidity conditions necessary for the maintenance of premises, basements and technical undergrounds; modernize the wastewater collection system from the recovering of the open gallery; perform weather protection of the joints of steel beams of the gallery ceiling with columns; perform corrosion protection of steel structures; perform a number of works to protect the outer walls of the building structure and the technical base from moisture; to constantly monitor the condition of the building.

Wastewater pipe condition rating model using K- Nearest Neighbors

Risk-based assessment in pipe conditions mainly focuses on prioritizing the most critical assets by evaluating the risk of pipe failure. This paper's goal is to classify a comprehensive pipe rating model which is obtained based on a series of pipe pipe, external, and hydraulic characteristics that are identified for the proposed methodology. The traditional manual method of assessing sewage structural conditions takes a long time. By building an automated process using K-Nearest Neighbors (K-NN), this study presents an effective technique to automate the identification of the pipe defect rating using the pipe repair data. First, we performed the Shapiro Wilks Test for 1240 data from the Dept. of Engineering & Environmental Services, Shreveport, Louisiana Phase 3 with 12 variables to determine if factors could be incorporated into the final rating. We then developed a K-Nearest Neighbors model to classify the final rating from the statistically significant factors identified in Shapiro-Wilks Test. This classification process allows for recognizing the worst condition of wastewater pipes that need to be replaced immediately. This comprehensive model is built according to the industry-accepted and used guidelines to estimate the overall condition. Finally, for validation purposes, the proposed model is applied to a small portion of a US wastewater collection system in Shreveport, Louisiana.

Water strategies and practices for sustainable development in the semiconductor industry

Semiconductor manufacturing is a rapidly growing industry and water-intensive industry. Water strategy formulation and decisions can be crucial factors in realizing the sustainable development of the semiconductor industry. This study surveyed the sustainability reports of 24 semiconductor corporations and investigated their water strategies and practices. Water targets proposed in the early stage of the 21st century are summarized. Water recycling, reuse, and restoration were the main strategies. Reverse osmosis played a dominant role in water treatment and reclamation. Classified wastewater collection and separate treatment systems have contributed greatly to improvement of water recycling rate in industrial parks. Finally, a future water cycle system for semiconductor manufacturing parks is proposed, which comprises water source, water use and recycling, and water discharge. This study is of theoretical and practical significance for the formulation and implementation of water strategies in the semiconductor industry to help accomplish its sustainable development with rapid growth.

Leveraging an established neighbourhood-level, open access wastewater monitoring network to address public health priorities: a population-based study

Before the COVID-19 pandemic, the US opioid epidemic triggered a collaborative municipal and academic effort in Tempe, Arizona, which resulted in the world's first open access dashboard featuring neighbourhood-level trends informed by wastewater-based epidemiology (WBE). This study aimed to showcase how wastewater monitoring, once established and accepted by a community, could readily be adapted to respond to newly emerging public health priorities. In this population-based study in Greater Tempe, Arizona, an existing opioid monitoring WBE network was modified to track SARS-CoV-2 transmission through the analysis of 11 contiguous wastewater catchments. Flow-weighted and time-weighted 24 h composite samples of untreated wastewater were collected at each sampling location within the wastewater collection system for 3 days each week (Tuesday, Thursday, and Saturday) from April 1, 2020, to March 31, 2021 (Area 7 and Tempe St Luke's Hospital were added in July, 2020). Reverse transcription quantitative PCR targeting the E gene of SARS-CoV-2 isolated from the wastewater samples was used to determine the number of genome copies in each catchment. Newly detected clinical cases of COVID-19 by zip code within the City of Tempe, Arizona were reported daily by the Arizona Department of Health Services from May 23, 2020. Maricopa County-level new positive cases, COVID-19-related hospitalisations, deaths, and long-term care facility deaths per day are publicly available and were collected from the Maricopa County Epidemic Curve Dashboard. Viral loads of SARS-CoV-2 (genome copies per day) measured in wastewater from each catchment were aggregated at the zip code level and city level and compared with the clinically reported data using root mean square error to investigate early warning capability of WBE. Between April 1, 2020, and March 31, 2021, 1556 wastewater samples were analysed. Most locations showed two waves in viral levels peaking in June, 2020, and December, 2020-January, 2021. An additional wave of viral load was seen in catchments close to Arizona State University (Areas 6 and 7) at the beginning of the fall (autumn) semester in late August, 2020. Additionally, an early infection hotspot was detected in the Town of Guadalupe, Arizona, starting the week of May 4, 2020, that was successfully mitigated through targeted interventions. A shift in early warning potential of WBE was seen, from a leading (mean of 8·5 days [SD 2·1], June, 2020) to a lagging (-2·0 days [1·4], January, 2021) indicator compared with newly reported clinical cases. Lessons learned from leveraging an existing neighbourhood-level WBE reporting dashboard include: (1) community buy-in is key, (2) public data sharing is effective, and (3) sub-ZIP-code (postal code) data can help to pinpoint populations at risk, track intervention success in real time, and reveal the effect of local clinical testing capacity on WBE's early warning capability. This successful demonstration of transitioning WBE efforts from opioids to COVID-19 encourages an expansion of WBE to tackle newly emerging and re-emerging threats (eg, mpox and polio). National Institutes of Health's RADx-rad initiative, National Science Foundation, Virginia G Piper Charitable Trust, J M Kaplan Fund, and The Flinn Foundation.