Drinking Water Production Research Articles

Detección de SARS-CoV-2 en aguas residuales como alerta temprana en el Área Metropolitana de la Ciudad de Buenos Aires (BAMA)

RESUMEN Agua y Saneamientos Argentinos S.A. (AySA) brinda servicios esenciales que abarcan la producción de agua potable y el tratamiento de aguas residuales para una población que supera los 14,5 millones de habitantes en el Área Metropolitana de Buenos Aires (AMBA), Argentina. En respuesta a la declaración de pandemia por COVID-19 por parte de la Organización Mundial de la Salud (OMS), AySA desarrolló una metodología para evaluar la carga genética viral del SARS-CoV-2 en aguas residuales sin tratar. Este enfoque tenía como objetivo aprovechar el potencial de la vigilancia epidemiológica basada en aguas residuales, basándose en experiencias internacionales. Para monitorear la carga viral en las secciones representativas del sistema de recolección de aguas residuales, empleamos una técnica de ultracentrifugación adaptada para concentrar muestras. Después de esto, se realizaron la extracción de ARN y RT-qPCR para cuantificar el gen Orf1ab del SARS-CoV-2. Este estudio se realizó de diciembre de 2020 a junio de 2021, para anticipar la segunda ola de la pandemia. Al analizar los datos de cuatro grandes plantas de tratamiento de aguas residuales, identificamos asociaciones estadísticamente significativas entre la carga genómica viral log10 y los casos positivos log10 informados una o dos semanas después. En base a los resultados obtenidos, concluimos que los niveles de virus del alcantarillado podrían ser un buen predictor de futuros casos clínicos a ser diagnosticados en un futuro inmediato.

Influence of colloidal iron oxide and natural organic matter fouling on nanofiltration membrane performance: role of feed composition and membrane properties

Iron oxide colloids and natural organic matter in the presence of divalent cations cause irreversible fouling for commonly used drinking water nanofiltration membranes.

Contribution of self-organizing maps in the classification of water resources in the production of drinking water by ultrafiltration

The ultrafiltration process has become essential in most drinking water production facilities. However, the variation in water quality remains difficult to manage, especially during major fouling phenomena. For this reason, the objective of this study is to develop a membrane fouling prediction tool based on seasonal water quality variation. For this, monthly monitoring of 6 water resources in Poitiers and Paris over 8 months was carried out, in which a filtration test was carried out on all the resources to assess their fouling potential and 13 physico-chemical parameters were measured. The collected data were used to build a self-organizing map (SOM) to classify water resources according to their fouling potential. The resulting SOM is able to classify the water resources according to the measured parameters into four clusters: (1) Waters with high TOC and turbidity with high fouling tendency, (2) Waters with average TOC and turbidity with average fouling tendency, (3) Waters with low TOC and turbidity that induce negligible fouling and (4) Very good quality waters that do not cause fouling.

Enhanced electrocoagulation process for natural organic matter removal from surface drinking water sources: coagulant dose control & organic matter characteristics

An optimized electrocoagulation process was investigated for enhanced removal of dissolved organic matter for eco-friendly drinking water production from surface water sources. A model-based control system was developed for electro-coagulant dosing.

Urban Expansion in The Erbil City and Its Impact on The Drinking Water Use Production

The city of Erbil, like any other region, is expanding because of the growing population, which has played a significant role in the production and use of drinking water. The aim of the research is to highlight the directions of erbil's population growth, the expansion of erbil city and the influence on use between 1950 and 2020, for this purpose, the number of neighborhoods has been taken as a measure during which time the number of neighborhoods in the year (2003-2010) reached 74 neighbourhoods, as well as the amount of water produced by Efraz water (1.2.3) and erbil city wells numbering 292 wells, the average water production reached (16,380) square meter per hour, but the amount of yield swells  One person reached about 100 litres a day, but in 2010-2020 the number of neighbourhoods in Erbil increased to 152 neighbourhoods, the amount of water produced in all three water projects. Efraz (1,2.3) and erbil's wells, which number 920, have reached drinking water production (25644114) Square meter in one hour and individual consumption has reached 400 litres of water in one day.

Assessment of the efficiency of drinking water service in Halabja city

The production and consumption of potable water is one of the important applied topics to which planning studies have been directed, due to the increased demand for drinking water consumption and its other uses. The cities of the world suffer from the problem of providing services, especially the problem of water supply, which is a global phenomenon that increases in severity in dry areas and cities far from rivers.The study aimed to reveal the working mechanism of the drinking water production projects supplied to the city of Halabja and to evaluate its qualitative, quantitative and distributive efficiency. It also revealed that the city is equipped with potable water from two major projects and (7) artesian wells that serve (39) residential localities with a population of (79,505) people in (2021), The study relied on the descriptive analytical method in studying the reality of potable water services. The study reached a set of related conclusions and recommendations presented at the end of the research, the most important of which is that the quantity of potable water produced in the Halabja water projects is sufficient to meet all uses in the city. The per capita share amounted to (450 liters / person / day) (in 2021), which is greater than the specific schematic standard of (250 liters / person / day), and the water produced in terms of quality, are identical with the Iraqi and international standards.

Anthracite Releases Aromatic Carbons and Reacts with Chlorine to Form Disinfection Byproducts in Drinking Water Production.

Anthracite is globally used as a filter material for water purification. Herein, it was found that up to 15 disinfection byproducts (DBPs) were formed in the chlorination of anthracite-filtered pure water, while the levels of DBPs were below the detection limit in the chlorination of zeolite-, quartz sand-, and porcelain sandstone-filtered pure water. In new-anthracite-filtered water, the levels of dissolved organic carbon (DOC), dissolved organic nitrogen (DON), and ammonia nitrogen (NH3-N) ranged from 266.3 to 305.4 μg/L, 37 to 61 μg/L, and 8.6 to 17.1 μg/L, respectively. In aged anthracite (collected from a filter at a DWTP after one year of operation) filtered water, the levels of the above substances ranged from 475.1 to 597.5 μg/L, 62.1 to 125.6 μg/L, and 14 to 28.9 μg/L, respectively. Anthracite would release dissolved substances into filtered water, and aged anthracite releases more substances than new anthracite. The released organics were partly (around 5%) composed by the μg/L level of toxic and carcinogenic aromatic carbons including pyridine, paraxylene, benzene, naphthalene, and phenanthrene, while over 95% of the released organics could not be identified. Organic carbon may be torn off from the carbon skeleton structure of anthracite due to hydrodynamic force in the water filtration process.

Multi-Criteria Decision-Making Analysis for the Selection of Desalination Technologies

Accessible fresh water resources for drinking and usage are very limited in our world. Furthermore, these limited fresh water resources are gradually decreasing due to climate change, industrialization, and population growth. Despite the ever-increasing need for water, the inadequacies in our resources have made it critical to develop alternative drinking and utility water production methods. Desalination, one of the most important alternatives for fresh water supply, is on the rise on a global scale. Desalination facilities use various thermal and membrane techniques to separate water and salt. Concentrated brine, which contains desalination chemicals and significant amounts of salt, and is formed in high volumes from desalination processes, is also a concern. This article compares various desalination techniques using a multi-criteria decision-making method. The findings show that the Reverse Osmosis & Membrane Crystallization process is the most preferred technology due to its cost advantages as well as operational efficiency. Similarly, Multistage flash &Electrodialysis, the least preferred alternative, has been criticized for its low cost-effectiveness. These results suggest that cost and operational efficiency will continue to be the main drivers in the evaluation of desalination technologies in the near future.

Phosphorus adsorption on iron-coated sand under reducing conditions.

Mitigation measures are needed to prevent large loads of phosphate originating in agriculture from reaching surface waters. Iron-coated sand (ICS) is a residual product from drinking water production. It has a high phosphate adsorption capacity and can be placed around tile drains, taking no extra space, which increases the farmers' acceptance. The main concern regarding the use of ICS filters below groundwater level is that limited oxygen supply and high organic matter concentrations may lead to the reduction and dissolution of iron (hydr)oxides present and the release of previously adsorbed phosphate. This study aimed to investigate phosphate adsorption on ICS at the onset of iron reduction. First, we investigated whether simultaneous metal reduction and phosphate adsorption were relevant at two field sites in the Netherlands that use ICS filters around tile drains. Second, the onset of microbially mediated reduction of ICS in drainage water was mimicked in complementary laboratory microcosm experiments by varying the intensity of reduction through controlling the oxygen availability and the concentration of degradable organic matter. After 3 yr, ICS filters in the field removed phosphorus under low redox conditions. Over 45 d, the microbial reduction of manganese and iron oxides did not lead to phosphate release, confirming field observations. Electron microscopy and X-ray absorption spectroscopy did not evince systematic structural or compositional changes; only under strongly reducing conditions did iron sulfides form in small percentages in the outer layer of the iron coating. Our results suggest that detrimental effects only become relevant after long periods of operation.

Removal of arsenic and selenium from brackish water using electrodialysis for drinking water production

Arsenic (As) and selenium (Se) are hazardous elements contaminating groundwater resources. In this work, arsenite (AsIII), selenite (SeIV) and selenate (SeVI) removal from brackish water by a batch electrodialysis (ED) system was investigated with varied water quality (pH, feed concentration and feed salinity) and operative parameters (flowrate and electric potential). The results showed that As and Se removal was pH dependent. Rising salinity increased the amount of chloride ions and therefore delayed As and Se removal. Higher As and Se feed concentrations led to higher molar flux, although removal rates were independent of ion concentration. ED boundary layer thickness was reduced at higher flowrates (30 to 70 L/h), but this did not affect the removal of contaminants significantly (<5 %). Electromigration transport was the dominant mechanism for both Se and As species removal, as long as the compounds were charged. The ionic characteristics (diffusivity, ionic mobility, hydration number) were the determinant principle for removal. As and Se real contaminated groundwater samples were tested showing that ED can potentially be used as a resource recovery method for selective removal of more mobile ions.

H2O2-Enhanced As(III) Removal from Natural Waters by Fe(III) Coagulation at Neutral pH Values and Comparison with the Conventional Fe(II)-H2O2 Fenton Process

Arsenic is a naturally occurring contaminant in waters, which is toxic and adversely affects human health. Therefore, treatment of water for arsenic removal is very important production of safe drinking water. Coagulation using Fe(III) salts is the most frequently applied technology for arsenic removal, but is efficient mostly for As(V) removal. As(III) removal usually requires the application of a pre-oxidation step, which is mainly conducted by chemical or biological means. In this study, we show that Fe(III) coagulation in the presence of H2O2 can be a very efficient treatment process for As(III) removal, which has been never been shown before in the literature. The results showed that addition of 8.7–43.7 mM hydrogen peroxide to Fe(III) coagulation process was able to increase the effectiveness of As(III) removal in synthetic groundwater by 15–20% providing residual concentrations well below the regulatory limit of 10 μg/L from initial As(III) concentrations of 100 μg/L, at pH 7. The enhanced coagulation process was affected by the solution pH. The removal efficiency substantially declined at alkaline pH values (pH &gt; 8). Addition of EDTA in the absence of H2O2 had a strong inhibiting effect where the As(III) removal was almost zero when 88.38 μΜ EDTA were used. Radical quenching experiments with 50, 100 and 200 mM DMSO, methanol and 2-propanol in the H2O2-coagulation process had a slightly adverse effect on the removal efficiency. This is considered as indicative of an adsorption/oxidation of As(III) process onto or very near the surface of iron oxide particles, formed by the hydrolysis of Ferric iron ions. In practice, the results suggest that addition of H2O2 increases the As(III) removal efficiency for Fe(III) coagulation systems. This is an important finding because the pre-oxidation step can be omitted with the addition of H2O2 while treating water contaminated with As(III).

Application of hazard analysis and critical control points concept for rural bottled drinking water production process

ABSTRACT Drinking water quality is one of the greatest factors affecting human health. The drinking water production process was investigated in 30 factories in Sakon Nakhon province, Thailand using hazard analysis and critical control points (HACCP) and water quality analysis. The results showed that the major hazards were pollution of the raw water source, final disinfection, personal hygiene of workers and drinking water quality. Overall, 28 samples contained total coliform bacteria, 23 samples were positive for fecal coliform bacteria and 16 samples contained Escherichia coli. These results suggested poor hygienic conditions in the water production process. To safeguard public health, more effort is required regarding a community program and strict regulation.

Effects of temperature and light exposure on the decay characteristics of fecal indicators, norovirus, and Legionella in mesocosms simulating subarctic river water

Knowledge of the decay characteristics of health-related microbes in surface waters is important for modeling the transportation of waterborne pathogens and for assessing their public health risks. Although water temperature and light exposure are major factors determining the decay characteristics of enteric microbes in surface waters, such effects have not been well studied in subarctic surface waters. This study comprehensively evaluated the effect of temperature and light on the decay characteristics of health-related microbes [Escherichia coli, enterococci, microbial source tracking markers (GenBac3 & HF183 assays), coliphages (F-specific and somatic), noroviruses GII and Legionella spp.] under simulated subarctic river water conditions. The experiments were conducted in four different laboratory settings (4 °C/dark, 15 °C/dark, 15 °C/light, and 22 °C/light). The T90 values (time required for a 90 % reduction in the population of a target) of all targets were higher under cold and dark (2.6–51.3 days depending upon targets) than under warm and light conditions (0.6–3.5 days). Under 4 °C/dark (simulated winter) water conditions, F-specific coliphages had 27.2 times higher, and coliform bacteria had 3.3 times higher T90 value than under 22 °C/light (simulated summer) water conditions. Bacterial molecular markers also displayed high variation in T90 values, with the greatest difference between 4 °C/dark and 22 °C/light recorded for HF183 DNA (20.6 times) and the lowest difference for EC23S857 RNA (6.6 times). E. coli, intestinal enterococci, and somatic coliphages were relatively more sensitive to light than water temperature, but F-specific coliphages, norovirus, and all bacterial rDNA and rRNA markers were relatively more sensitive to temperature than light exposure. Due to the slow microbial decay in winter under subarctic conditions, the microbial quality of river water might remain low for a long time after a sewage spill. This increased risk associated with fecal pollution during winter may deserve more attention, especially when river waters are used for drinking water production.

Perlindungan Hukum Konsumen: Efektivitas Pengawasan Produksi Air Minum Isi Ulang

&#x0D; This study aims to determine the effectiveness of supervision of the production of refilled drinking water and the role of the Consumer Dispute Settlement Agency in providing legal protection to consumers in Palu City. This study uses empirical legal research on the operation of law (law in action) in society. The results show that legal protection for consumers of refilled drinking water is the responsibility of local governments. Supervision of refilled drinking water production in Palu City needs to be more adequate than expected by consumers. The public does not fully know the Consumer Dispute Settlement Agency, so since its establishment until this research, there has never been a consumer dispute over refilled drinking water before being tried at the Palu City Consumer Dispute Settlement Agency. Therefore, it is necessary to provide guidance and outreach to the community regarding the feasibility of refilling drinking water and the institutional existence of the Consumer Dispute Settlement Agency.&#x0D;

Analysis of Drinking Water treatment costs – with an Application to Groundwater Purification Valuation

Understanding the factors affecting drinking water production costs is crucial for choosing a cost-effective solution for public drinking water supply systems. An important determinant of water treatment costs is the purification of raw water. Despite water purification being a well-acknowledged ecosystem service, its monetary value has not been assessed much yet. We present the first study analysing the determinants of drinking water production costs and valuating groundwater purification in the Czech Republic. We tested the impact of the type of raw water, the amount of drinking water produced, electric power consumption and treatment technologies and chemicals. The results suggested that drinking water production from groundwater was cheaper than from surface water. Even though drinking water production from groundwater was cheaper than from surface water, the application of some technologies, for example, chlorine or manganese removal, increased the production cost. Hence groundwater production costs can exceed surface water production costs. The outcome of the regression was applied for the valuation of groundwater purification. The valuation was further used for the development of monetary drinking water accounts within the System of Environmental- Economic Accounting – Ecosystem Accounting.

Review: Current understanding on biological filtration for the removal of microcystins

Harmful algal blooms (HABs) have become a global problem not only in aquatic habitats but also in public health and safety due to the production of cyanotoxins as their secondary metabolites. Among the various identified cyanotoxin groups, microcystins (MCs) are one of the most prevalent cyanotoxin detected during HABs. Different strategies including advanced physical and chemical treatment processes have been developed to mitigate the threat of cyanotoxins in water utilities, but these have revealed certain limitations in terms of high operational costs, low removal efficacy, and harmful by-products formation. Recently, biological filtration systems (BFS) have gained attention for safe drinking water production as they can treat various natural organic matter (NOM) and emerging contaminants through a highly efficient and environmentally sustainable process. However, limited attention has been given to understand the current research progress, research challenges, and knowledge gaps for the successful implementation of BFS for MC removal. Therefore, in this review, currently identified MC biodegradation pathways and MC-degrading microorganisms with their degradation rates are summarized, which may be pivotal for studying bioaugmented BFS to enhance the MC removal during HABs. Moreover, both laboratory and field studies on BFS for MC removal are reviewed, followed by a discussion of current challenges and future research needs for the practical application of BFS.

On improving the system of the management of the drinking water quality under implementation of federal project «Clean water»

Introduction. During the implementation of the federal project “Clean Water”, the Federal Service for Supervision in Protection of the Rights of Consumer and Man Wellbeing (Rospotrebnadzor) provides the following directions: control over the implementation of target indicators of the federal project “Clean Water”; improving the efficiency of the control for the drinking water quality; methodological support for the management of the assessment and monitoring for drinking water quality, and informing the population about drinking water quality. The purpose of the study: analysis of the implementation of measures by Rospotrebnadzor to achieve the targets of the federal project “Clean Water” with the subsequent development of proposals for improving the control for drinking water quality. Materials and methods. The study used the forms of federal statistical observation: No. 18, No. 2-20; federal information fund of social and hygienic monitoring data, state report “On the state of sanitary and epidemiological well-being of the population in the Russian Federation in 2021”. The methods of system and content analysis are applied in the work. Results. During the period of the federal project “Clean Water” Rospotrebnadzor has equipped laboratories with modern equipment. Guidelines have been developed and approved for drinking water quality assessment and organizing its monitoring, laboratory control, and conducting a water quality integral assessment. An information system has been developed to inform the population about the drinking water quality. Limitations. The study did not take into account the results of drinking water production control. This is due to the difficulties of collecting information, its standardization and analysis. Conclusion. A system for drinking water quality monitoring in the Russian Federation has been established. Methodological support for drinking water quality monitoring and assessment has been developed, and public information about drinking water quality has been managed. The following questions need to be further addressed: it is necessary to update social and hygienic monitoring programs, organize the receipt and exchange of information on the results of production control of the quality of drinking water, moderate the procedure for assessing the risk to public health.

Role of ammonia-oxidizing microorganisms in the removal of organic micropollutants during simulated riverbank filtration

Biodegradation plays an important role in the removal of organic micropollutants (OMPs) during riverbank filtration (RBF) for drinking water production. The ability of ammonia-oxidizing microorganisms (AOM) to remove OMPs has attracted increasing attention. However, the distribution of AOM in RBF and its role in the degradation of OMPs remains unknown. In this study, the behavior of 128 selected OMPs and the distribution of AOM and their roles in the degradation of OMPs in RBF were explored by column and batch experiments simulating the first meter of the riverbank. The results showed that the selected OMPs were effectively removed (82/128 OMPs, >70% removal) primarily by biodegradation and partly by adsorption. Inefficiently removed OMPs tended to have low molecular weights, low log P, and contain secondary amides, secondary sulfonamides, secondary ketimines, and benzyls. In terms of the microbial communities, the relative abundance of AOM increased from 0.1%–0.2% (inlet-sand) to 5.3%–5.9% (outlet-sand), which was dominated by ammonia-oxidizing archaea whose relative abundance increased from 23%–72% (inlet-sand) to 97% (outlet-sand). Comammox accounted for 23%–64% in the inlet-sand and 1% in the outlet-sand. The abundances of AOM amoA genes kept stable in the inlet-sand of control columns, while decreased by 78% in the treatment columns, suggesting the inhibition effect of allylthiourea (ATU) on AOM. It is observed that AOM played an important role in the degradation of OMPs, where its inhibition led to the corresponding inhibition of 32 OMPs (5/32 were completely suppressed). In particular, OMPs with low molecular weights and containing primary amides, secondary amides, benzyls, and secondary sulfonamides were more likely to be removed by AOM. This study reveals the vital role of AOM in the removal of OMPs, deepens our understanding of the degradation of OMPs in RBF, and offers valuable insights into the physiochemical properties of OMPs and their AOM co-metabolic potential.

Physically-assisted removal of organic fouling by osmotic backwashing coupled with chemical cleaning

Membrane filtration is a robust water treatment method against membrane fouling driven by natural organic matters for drinking water production and wastewater reclamation. Despite recent studies revealing that osmotic backwashing (OBW) can effectively remove organic fouling from the membrane, the mechanism of fouling removal and the supportive effect of OBW remains unexplored. Here, we performed a comparative analysis of chemical cleaning and OBW-assisted chemical cleaning to remove organic fouling from the reverse osmosis membrane. Natural organic matters such as humic acid, sodium alginate, and tannic acid were used as model foulants. Various in-situ monitoring and ex-situ characterization methods were used to evaluate direct and indirect effects on membrane cleaning. Using OBW increased the water permeability coefficient of the fouled membrane compared to using chemical cleaning solely, improving the water flux up to 10.8%. Notably, in-situ monitoring revealed that pore generation below the fouling layer readily dissociated the fouling layer and helped the cleaning agent encounter foulants rapidly. The characterization of the fouled membrane demonstrated that applying OBW before chemical cleaning could enhance the membrane cleaning efficiency.

Understanding short-term organic matter fluctuations to optimize drinking water treatment

Abstract Increases in organic content and the resulting browning of freshwater are a current and growing challenge for the ecology of these waters, leading to the need for more efforts in drinking water production. This study investigated the implications of short-term changes in the water quality from Lake Bolmen on the treatment process at the downstream located at the Ringsjö water treatment plant. The main objective was to understand short-term organic matter fluctuations to efficiently manage drinking water treatment. The ability to make predictions about expected raw water quality based on variations in the watershed and upstream waters facilitates optimal adjustment of drinking water treatment processes. Key elements in the water supply system studied included a tunnel and pipeline system and a sub-basin of Lake Bolmen. A wealth of data were available for the analysis to establish temporal and spatial properties of the water quality in the system and its dependence on the governing factors. The main factors controlling water quality were identified, both regarding the transport in the tunnel and through the sub-basin, including surface runoff, hydrodynamic properties, sedimentation, resuspension, and biomass availability. Although a particular case was investigated, the study has implications for improving drinking water treatment.