High-quality Water Research Articles

A Hybrid Improved Dual-Channel and Dual-Attention Mechanism Model for Water Quality Prediction in Nearshore Aquaculture

The aquatic environment in aquaculture serves as the foundation for the survival and growth of aquatic animals, while a high-quality water environment is a necessary condition for promoting efficient and healthy aquaculture development. To effectively guide early warnings and the regulation of water quality in aquaculture, this study proposes a predictive model based on a dual-channel and dual-attention mechanism, namely, the DAM-ResNet-LSTM model. This model encompasses two parallel feature extraction channels: a residual network (ResNet) and long short-term memory (LSTM), with dual-attention mechanisms integrated into each channel to enhance the model’s feature representation capabilities. Then, the proposed model is trained, validated, and tested using water quality and meteorological parameter data collected by an offshore farm environmental monitoring system. The results demonstrate that the proposed dual-channel structure and dual-attention mechanism can significantly improve the predictive performance of the model. The prediction accuracy for pH, dissolved oxygen (DO), and salinity (SAL) (with Nash coefficients of 0.9361, 0.9396, and 0.9342, respectively) is higher than that for chemical oxygen demand (COD), ammonia nitrogen (NH3-N), nitrite (NO2−), and active phosphate (AP) (with Nash coefficients of 0.8578, 0.8542, 0.8372, and 0.8294, respectively). Compared to the single-channel model DA-ResNet (ResNet integrated with the proposed dual-attention mechanism), the Nash coefficients for predicting pH, DO, SAL, COD, NH3-N, NO2−, and AP increase by 12.76%, 12.58%, 11.68%, 18.350%, 19.32%, 16%, and 14.99%, respectively. Compared to the single-channel DA-LSTM model (LSTM integrated with the proposed dual-attention mechanism), the corresponding increases in Nash coefficients are 9.15%, 9.93%, 9.11%, 10.91%, 10.11%, 10.39%, and 10.2%, respectively. Compared to the ResNet-LSTM (ResNet and LSTM in parallel) model without the attention mechanism, the improvements in Nash coefficients are 1.91%, 2.4%, 0.74%, 3.41%, 2.71%, 3.55%, and 4.13%, respectively. The predictive performance of the model fulfills the practical requirements for accurate forecasting of water quality in nearshore aquaculture.

First report of a major management target species, chironomid Paratanytarsus grimmii (Diptera: Chironomidae) larvae, in drinking water treatment plants (DWTPs) in South Korea.

Ensuring the supply of safe and high-quality drinking water can be compromised by the presence of chironomid larvae in drinking water treatment plants (DWTPs), which may contaminate municipal water systems through freshwater resources. Chironomids are dominant species known for their resilience to a broad range of extreme aquatic environments. This study aimed to identify the morphological characteristics and obtain genetic information of the chironomid Paratanytarsus grimmii found in the water intake source and freshwater resource of DWTPs in Korea, highlighting the potential possibility of a parthenogenetic chironomid outbreak within DWTP networks. The distribution of chironomid larvae at the water intake source site (DY) of the Danyang DWTP and the freshwater resource (ND) of the Nakdong River was investigated. A total of 180 chironomid individuals, encompassing three subfamilies and six species from six 6 genera were identified at the DY site, with Procladius nigriventris being the dominant species. At the ND site, fifty chironomid individuals, encompassing two subfamilies and six species from six genera, were identified, with Cricotopus sylvestris being the dominant species. The morphological characteristics of the head capsule, mentum, mandible, and antennae of six P. grimmii larvae collected from the DY and ND sites were characterized. DNA barcoding and phylogenetic analysis revealed distinct mitochondrial diversities between the P. grimmii larvae from DY and those from ND. These results provide crucial information for the morphological identification and DNA barcoding of the key management target chironomid P. grimmii larvae, which can be used to detect the occurrence of this chironomid species in DWTPs.

Leveraging almost hydrophobic PVDF membrane and in-situ ozonation in O3/UF/BAC system for superior anti-fouling and rejection performance in drinking water treatment.

The almost hydrophobic PVDF membrane (PVDF matrix) commonly exhibited excellent performance in pollutant rejection but with poor anti-fouling performance. This study intended to develop the rejection performance and enhance anti-fouling of the PVDF membrane in an O3/UF/BAC system for high quality water production through leveraging the advantages of in-situ ozonation and the nature of the PVDF membrane. Reduced density gradient (RDG) analysis demonstrated that the PVDF membrane exhibited excellent ozone resistance by reducing hydrogen bonds and electrostatic interactions between the membrane surface and ozone. Consequently, the physicochemical properties of the PVDF membrane remained unchanged in the laboratory continuous flow experiment with in-situ ozonation at 2.86 mg/L. The almost hydrophobicity of the PVDF membrane not only resisted fouling but also facilitated the reaction between ozone and foulants of higher concentrations locally at membrane surface, leading to dynamic changes in membrane fouling, with TMP/TMP0 initially increasing, then decreasing and stable. Therefore, the Rtotal, Rcake and Rgel of the PVDF membrane decreased by 47.40 %, 46.79 % and 50.99 % as compared to the UF/BAC system, respectively, in the O3/UF/BAC system. In-situ ozonation transformed macromolecular substances into micromolecules, particularly organic matter with lignin/carboxylic-rich alicyclic molecules and aromatic structures. The majority of these micromolecules were either rejected by the deposited foulants layer through Van der Waals interaction and utilized as a carbon source by membrane surface microorganisms (eg., Curvibacter and Methyloversatilis), or further degraded by microorganism in the BAC unit. This resulted in a 19.34 % and 40.58 % reduction in CODMn concentrations in the UF and BAC effluents, respectively. The system's anti-fouling and water purification performance observed in laboratory experiments was confirmed in a pilot test, providing new insights into the use of in-situ ozonation and organic membranes.

Description of a novel filamentous cyanobacterial species of Leptodesmis (Leptolyngbyaceae, Cyanobacteria) in China based on the polyphasic approach

The middle route of the South-to-North Water Diversion Project supplies high-quality water to various water treatment plants along its path and increases the diversity of cyanobacteria present in the raw water. A filamentous cyanobacterium Leptodesmis xinxiangensis HNU2023 was successfully isolated from a drinking water plant in Xinxiang, which receives its water supply from this middle route. Morphologically, this strain exhibits similarities to cyanobacterial taxa within the genera Leptodesmis and Phormidesmis. Phylogenetic analysis, based on 16S rRNA gene sequences, indicates that this strain is closely related to Leptodesmis, forming a well-supported clade. The 16S rRNA gene sequences of the strain show between 95.5% and 98% similarity to known Leptodesmis species, suggesting that it represents a new species within this genus. Moreover, the distinctive patterns observed in the D1-D1′ and Box-B helix regions of the 16S–23S rRNA internal transcribed spacer (ITS) secondary structure further confirm that this strain is a novel species. Consequently, the comprehensive analysis of the isolated strain, in conjunction with morphological characteristics, 16S rRNA gene sequencing, and ITS secondary structure, substantiates the classification of Leptodesmis xinxiangensis sp. nov. as a new species within the genus Leptodesmis.

Innovative Gravity-Fed Filtration System to Improve Coastal Community Water Quality

Efforts to meet clean water needs, especially for drinking water, depend on the condition of groundwater that is healthy and sufficiently available. Filtration is the process of separating particles from a liquid by passing the liquid through a permeable material. This study examines the Gravity-Fed Filtering System with innovative Imhoff technology, combined with a Primary Treatment stage, to produce clearer and higher-quality water. The objective of this research is to assess the effectiveness of this system in reducing contamination levels in groundwater, including iron (Fe), manganese (Mn), total hardness (Ca and Mg), and organic compounds. The study employed an experimental method with a quantitative approach and used a One Group Pretest-Posttest design. The research was conducted in two locations: Barombong Village in Makassar and Pauwo Village in Gorontalo. Fifteen samples were randomly selected for analysis. The study began with preliminary observations and initial testing in March 2022, followed by the main research and prototype evaluation in 2023-2024. The results show that the system effectively reduced Fe, Mn, organic compounds, and total hardness levels. In Makassar, the highest reduction in Fe is 87.3% in sample 8, while in Gorontalo, the highest reduction is 93.3% in sample 8. The highest reduction in manganese (Mn) in Makassar is 63.3% in sample 1, and in Gorontalo, it is 62.1% in sample 1. The highest reduction in organic compounds in Makassar is 81.6% in sample 3, while the lowest reduction in total hardness in Makassar is 77.1% in samples 4, 5, 6, and 10. In Gorontalo, the highest reduction in total hardness is 90.3% in samples 1, 2, and 3. Recommendations for the community, The use of gravity-fed filtering system technology as one of the media used to reduce iron and manganese concentrations is considered quite good, but for similar research to be carried out, modifications should be made to the media specifically starting with the size, shape and other variables that support it so that it is more effective in reducing pollutant concentrations.

Groundwater well fields in ice-margin valley aquifers - is it easy to protect them, or not? An overview of hydrogeological and legal aspects of determining wellhead protection zones

This paper discusses principles for delineating wellhead protection zones (WHPZ) of groundwater well fields in ice-margin valleys. A distinctive feature of such well fields is that, apart from the often geogenically contaminated water of ice-margin valleys, they are largely supplied with high-quality water from intertill aquifers of neighbouring uplands. However, much of this inflow can be intercepted by wells for agriculture that are increasingly being constructed in the capture zones of existing municipal well fields, thus posing a threat to the quality of water for the public. This problem has been investigated using the example of a municipal well in Wroniawy (Poland) by analysing changes in the recharge components of this well field with a groundwater flow model. The results indicate that the commissioning of agricultural abstractions in the capture zone of this well field reduces inflow from intertill aquifers (8.5 per cent) and precipitation recharge (3.3 per cent), following a change in the extent of the capture zone. The loss of these qualitative recharge components is substituted by an increase in poor-quality water, i.e., surface water (7.3 per cent) and geogenically contaminated water from the ice-margin valley centre (3.8 per cent). Protecting well fields in such locations from adverse water quality changes requires the implementation of quantitative shielding of best-quality water, calling for WHPZ to cover the entire capture zone regardless of water flow timing, which is not provided for in Polish legislation. Costs and constraints of implementing such a WHPZ can be reduced by dividing it into sectors that differ in the scope of limitations, with the only quantitative protection applied to the outermost, medium- and low-vulnerable parts of the capture zone.

Research on Impact of Equity Costs and Environmental Costs on Supply-Side Classified Water Pricing

The classified water pricing system is an effective measure for promoting the rational utilization of water resources under market mechanisms. Studying the water prices of three different types of water sources, including reservoir water, river water, and wastewater treatment plant effluent, is the basis for promoting the use of reclaimed water. However, there remains a spectrum of viewpoints on how to establish a pricing mechanism for reclaimed water at present. This study primarily focuses on the multi-level quality-separated water supply system in Yiwu City, China. It analyzes the limitations of the current water pricing formation mechanism and the externality of integrating reclaimed water into the unified allocation of multiple water sources. Based on the principles of full-cost water pricing and externality theory, a supply-side classified water pricing permit cost and pricing calculation model, covering the entire process of the social water cycle, is proposed. It focuses on the analysis of the impact of equity costs and environmental costs on supply-side classified water pricing. The Shapley value method is used for the technology of cost allocation among stakeholders to reasonably distribute the calculated water pricing of reclaimed water. The price of reclaimed water varies depending on the user type, with residential users paying 2.93 CNY/t, industrial users 4.00 CNY/t, and government allocations at 8.52 CNY/t. Compared with the classified water prices of various stakeholders on the user side of reservoir water, reclaimed water has a significant price advantage. This research demonstrates that the supply-side classified water pricing model, which includes a permit cost and pricing calculation framework, can encourage the supply of higher-quality water at corresponding higher prices, while also providing the internalization of external costs. Furthermore, the Shapley value method of cost allocation can realize the fair burden of stakeholders on the calculated water price and maintain the competitive advantage of reclaimed water prices.

A LINEAR PROGRAMMING APPROACH TO OPTIMIZING ENVIRONMENTAL RESOURCE MANAGEMENT IN URBAN AREAS

This study investigates the optimization of environmental resource management in urban settings using a linear programming approach, focusing on ammonia production and wastewater management. The model addresses uncertainties in resource allocation by evaluating the cost implications of wastewater discharge during production. Key variables include water drawn from rivers, sludge discharge, and energy consumption. The study explores scenarios where zero-discharge policies are implemented, resulting in reduced water usage but increased energy consumption and higher production costs. The methodology employed linear programming to minimize the cost of ammonia production while ensuring water quality through regulated waste disposal. The findings indicate that minimizing river impurities through controlled waste discharge reduces water usage but escalates energy consumption, complicating cost management. Results from the numerical example show that under optimal conditions, 6,666.7 liters of water and 555.6 kg of sludge are needed to produce 41,666.7 kg of ammonia, with zero energy consumption in the process. The significance of these results lies in their potential to inform sustainable urban resource management policies that balance economic and environmental priorities. The study concludes that while achieving high water quality increases costs, it is crucial for sustainable ammonia production and environmental conservation, particularly in minimizing the ecological impact of industrial activities on water resources.

Hydrogeochemistry, Water Quality, and Health Risk Analysis of Phreatic Groundwater in the Urban Area of Yibin City, Southwestern China

With rapid urbanization, intensified agricultural activities, and industrialization, groundwater resources are increasingly threatened by pollution. Industrial wastewater discharge and the extensive use of agricultural fertilizers in particular, have had substantial impacts on groundwater quality. This study examines 18 groundwater samples collected from the main urban area of Yibin City to assess hydrochemical characteristics, spatial distribution, source attribution, water quality, and human health risks. Statistical analysis reveals significant exceedances in TDS, NO3−, Mn, and As levels in groundwater, with elevated concentrations of B as well. Isotopic analysis identifies atmospheric rainfall as the primary recharge source for groundwater in the area, with water–rock interactions and limestone dissolution playing key roles in shaping its chemical composition. Applying the Entropy-Weighted Water Quality Index (EWQI) for a comprehensive water quality assessment, the study found that 94.44% of groundwater samples were rated as “good”, indicating relatively high overall water quality. Deterministic health risk assessments indicate that 72.22% of the groundwater samples have non-carcinogenic health risks below the threshold of 1, while 66.67% have carcinogenic health risks below 1.00 × 10−4. Monte Carlo simulations produced similar results, reinforcing the reliability of the health risk assessment. Although the study area’s groundwater quality is generally good, a significant human health risk persists, underscoring the need to ensure the safety of drinking and household water for local residents. This study provides a valuable reference for the rational management and remediation of groundwater resources.

Perspectives for improving deironing technologies groundwater for local drinking systems

In order to provide the population with high-quality drinking water, it is more expedient to focus on the use of underground sources of water supply, which are better protected from pollution in comparison with surface waters. However, a significant part of the underground sources of water supply is characterized by a high iron content, and the water from them needs to be deironed before being supplied to consumers. Removal of excessive iron content from underground water can be carried out by reagent or reagent-free methods, using water deiron installations of various design schemes and resorting to measures that increase the efficiency of their work. On the basis of the analysis of existing technologies for removing iron from groundwater and modern trends in the field of water purification, it is proposed for local water supply systems to use a filter with an automatic control valve and a technology that provides for reagent-free iron removal of groundwater due to the oxidation of dissolved iron with air cushion oxygen and further detention of the sediment formed in the layer of the multicomponent filter load. This technology is characterized by low cost and wear resistance of natural filter materials, ease of operation, environmental friendliness, which excludes secondary contamination of purified water with reagents, compactness and automation of control processes, which is especially relevant for small settlements.

Chemical characteristics and evolution of groundwater in northeastern margin of the Tibetan Plateau, China.

With the excellent water quality, abundant water quantity and convenient and economical exploitation conditions, groundwater has become an important water source for the social and economic development and people's livelihood in the northeast margin of the Tibetan Plateau in China. This study employed geostatistics, mineral saturation index, Gibbs diagram, ion ratio coefficient, chloralkali index and other methods to reveal the chemical distribution characteristics, evolution law and hydrogeochemical formation mechanism of groundwater in the northeastern margin of the Tibetan Plateau. The results showed that the contents of main chemical components of groundwater in Beichuan increased continuously from 1980 to 2020 complicating the types of hydrochemistry due to intensive groundwater exploitation and potential pollution from chemical plants. In contrast, Xinachuan, Xichuan, and Nanchuan witnessed an initial increase followed by a decrease in chemical components, simplifying hydrochemical types. The groundwater exhibited a spatial pattern of widespread high-quality water with sporadic banded and island brackish water. Chemical concentrations gradually rose along the groundwater flow direction. The leaching intensity of minerals by groundwater follows the order: halite > gypsum > calcite > dolomite. Leaching, cation exchange, and human activities are identified as the primary drivers of the chemical field evolution in the Xining area. The presence of Tertiary strata, rich in soluble salts like gypsum and halite, influences water-rock interactions, leading to downstream TDS increases and gradual salinization. Centralized pumping well exploitation altered groundwater runoff intensity and direction, contributing to high TDS areas near water sources and industrial parks, exacerbated by artificial pollution. The above conclusions are of great theoretical and practical significance to realize sustainable utilization of water resources and important for urban development in the northeastern margin of the Tibetan Plateau.

Exploring optimal soil conditions for high-functional Oenanthe javanica (water dropwort) production.

Oenanthe javanica (Blume) DC., also known as water dropwort, is an aquatic plant species native to various regions across Asia. Despite its numerous health-promoting effects, research on improving its quality remains limited. The present study aimed to identify the optimal soil conditions required for high-quality water dropwort production. Fifty crop and soil samples from South Korean farms were analyzed for their functional content, soil chemical properties and plant tissue components. The results indicated that crop samples with lower functional components had higher soil pH, electrical conductivity (EC) and exchangeable cations than those with higher functional components. High-quality crop samples exhibited neutral soil pH and low EC values, suggesting better nutrient availability for crop growth and reduced salt stress as a result of mineral accumulation in soil. These findings suggest that soils affected by excessive salinity may create suboptimal soil conditions for water dropwort cultivation, potentially compromising crop quality. © 2024 Society of Chemical Industry.

An Intercomparison of DOC Estimated From fDOM Sensors in Wildfire Affected Streams of the Western United States

ABSTRACTWildfires in the western United States (US) have been demonstrated to affect water quality, including dissolved organic carbon (DOC), in streams. Elevated post‐wildfire DOC concentration poses a potential risk to drinking water treatment systems. In‐stream measurements of fluorescent dissolved organic matter (fDOM), a proxy for DOC, have shown potential to detect dynamic changes in DOC. High frequency monitoring of water temperature, turbidity, and fDOM was used in conjunction with discrete sampling during targeted storm events and at fixed intervals to estimate DOC in five western US streams following wildfires in 2020 and 2021 with the objective to characterise and compare responses to wildfire among sites. The elevated turbidity conditions typical after wildfire presented a challenge to fDOM measurements and there was a need to identify appropriate turbidity corrections at burned sites. A combination of established and novel methods corrected fDOM concentrations for turbidity effects up to 800 Formazin nephelometric units (FNU). Pre‐wildfire high frequency water quality data in adjacent burned and unburned watersheds allowed for separation of climate effects on DOC at one of the sites. Hydrology, climate and landcover were more important drivers of post‐wildfire DOC yield than wildfire characteristics. Seasonal patterns of DOC were unchanged by wildfire in snowmelt‐driven watersheds. Large, transient spikes in DOC concentration following frontal and convective storms were observed post‐wildfire at all burned sites, but not at the unburned site. These spikes often exceeded operational thresholds for drinking water treatment. This study highlights the ability to develop high frequency DOC estimates in surface waters up to 800 FNU using fDOM sensors and targeted storm sampling and emphasises the value of high frequency pre‐wildfire data in adjacent burned and unburned watersheds for separating climate and wildfire effects.

Adsorption‐enhanced Fenton catalytic membrane for high-efficiency, high-quality drinking water treatment

To efficiently remove micropollutants from drinking water, this study developed an adsorption-enhanced Fenton catalytic membrane with a two-dimensional structure composed of graphene oxide loaded with iron-cyclodextrin metal-organic frameworks (FeCD-MOF). As water passes through the interlayer channels, micropollutants and hydrogen peroxide (H2O2) are adsorbed into the voids of the FeCD-MOF and the cavities of the CD. This process increases the concentration of micropollutants and H2O2 in the confined space, thereby significantly enhancing the efficiency of the Fenton catalytic reaction. Under a constant flux of 90 L/m2h and influent concentrations of 10 mg/L bisphenol A (BPA) and 3 mM H2O2, the membrane consistently maintained over 97.4 % BPA removal for 72 h. FeCD-MOF’s excellent adsorption properties also enhance the stability of the treated water quality. Even with sudden increases in micropollutant concentration or interruptions in oxidant supply, the membrane maintained over 89.7 % BPA removal for an extended period solely through its adsorption capacity. Experimental results demonstrate that the membrane effectively removes various micropollutants, performs stably across a wide pH range, and resists interference from natural organic matter and ions, making it highly promising for drinking water treatment. Furthermore, compared to other MOF materials, FeCD-MOF has a significantly lower cost, enhancing its practicality.

Estimating the vertical profile of water quality variables in reservoirs: Application of remotely sensed data and machine learning techniques

Water quality assessment and management of reservoirs depend on accurate, large-scale, and continuous monitoring of the vertical profile of Water Quality Variables (WQVs). Remote sensing data have been widely used to retrieve high spatiotemporal water quality data; however, their application has practically been limited to evaluating surface WQVs. In this paper, a novel and efficient approach is introduced for assessing the profile of WQVs in reservoirs that depend on stratification, by taking into account the shape of profile as prior knowledge. First, an appropriate function is fitted to the WQVs vertical profile, and second, the parameters of that function as representative of the WQVs vertical profile are estimated using machine learning techniques. The model's inputs are day, maximum depth of point, and remote sensing data. Finally, PAWN sensitivity analysis is applied to show the extent to which each input influences different parts of the vertical profile. This method is applied in the Wadi Dayqah Reservoir, the largest dam in Oman, to evaluate water temperature, dissolved oxygen, pH, and chlorophyll-a profile. The results show that the predicted profiles are properly representative of in situ measurements, with a mean absolute error of 0.28 °C, 0.25 mg/L, 0.052, and 0.33 μg/L on test data sets of water temperature, dissolved oxygen, pH, and chlorophyll-a, respectively. Finally, PAWN sensitivity analysis illustrates that satellite data not only influence the parameters representing surface WQVs but also contribute to the estimation of other curve parameters.

Unravelling integrated groundwater management in pollution-prone agricultural cities: A synergistic approach combining probabilistic risk, source apportionment and artificial intelligence

Groundwater is vital for agricultural cities, but intensive farming and fertilizer use have increased contamination risks, particularly for non-carcinogenic health hazards. This study reveals the sources of contaminants in groundwater, their health impacts, and targeted strategies in such cities. The study analyzed 115 groundwater samples, with the main groundwater chemical type being HCO₃-Na·Ca. Significant exceedances were found in Mg²⁺, HCO₃−, F−, total hardness (TH), and Mn, with HCO₃− and Mg²⁺ surpassing standards in nearly all samples. The average Comprehensive Environmental Water Quality Index (CEWQI) was 100.68, indicating that overall groundwater quality in the study area is good. High-quality water is mainly found near reservoirs and rivers, while urban and eastern regions have relatively poorer water quality. The proportion of groundwater unsuitable for drinking is low. Monte Carlo risk assessments revealed that F− and NO₃− pose non-carcinogenic risks to both adults and children, with NO₃− presenting a higher potential health risk. The Positive Matrix Factorization (PMF) model identified that groundwater pollution primarily results from natural geological processes and human activities, with agriculture being the major anthropogenic factor. AI-based zoning strategies highlighted industrial areas and high-fluoride zones as critical areas requiring enhanced prevention and control measures.

A self-sufficient catalytic nanofiber evaporator for solar-driven efficient water purification through in-situ hydrogen peroxide generation

Solar-driven interfacial water evaporation (SDIWE) is an emerging technology for the production of clean water driven by inexhaustible energy source, but its application suffers from volatile organic compounds (VOCs) escaping into condensate water. Herein, a bifunctional SDIWE system integrated with Fenton process was proposed to achieve self-sufficient (not adding any additional chemicals to feed water) high-quality freshwater production from VOCs-contained wastewater through in-situ hydrogen peroxide (H2O2) generation. The hybrid SDIWE system based on AgNPs (Ag nanoparticles)@graphitic carbon nitride (g-C3N4)/beta-iron hydroxide oxide (β-FeOOH)-Polyacrylonitrile (AgG/Fe-PAN) nanofiber membrane exhibited an excellent evaporation performance (1.61 kg m-2h−1) under one sun (1 kW m−2). Significantly, in the absence of external oxidant source, the phenol removal rate in condensate water reached 98.4 ± 0.2 % due to the synergic photocatalysis technology and Fenton reaction, which was 6.1 times that of sole SDIWE (16.2 ± 0.5 %). Mechanism analysis reveals that H2O2 was effectively in-situ generated by AgNPs@g-C3N4 particles (∼18.8 μM at 4 h). Subsequently, the produced H2O2 was further activated to •OH radicals via β-FeOOH that ensures the VOCs decomposition during rapid steam generation. Meanwhile, the hybrid system not only exhibited an excellent phenol removal rate of 91.6 ± 0.6 % in wide pH ranges (1–11), but also ensured a good removal performance for various organic pollutants and excellent antibacterial properties. To sum up, the hybrid system has successfully integrated SDIWE technology with various advanced oxidation processes (AOPs), providing a novel way for the pollution-free production of high-quality clean water during the SDIWE process for water purification.

Muddy Waters: Design Thinking for Understanding the Multi-Organizational Problem Space of the Water Sector

Context and motivation: Climate change is manifested by climate variability, rising temperatures (and thus evaporation), and extreme events such as droughts and floods, which have a profound effect on the availability of natural resources, for example, high-quality water. While several technologies for addressing these challenges are available, their adoption is not widespread. In this study, a design thinking (DT) approach was applied to understand the problem space of floods and their handling by the Israeli water sector. Specifically, we aim at addressing the following question: What are the gaps in and barriers to adopting solutions that address sewerage flooding during extreme heavy rainfall events? The DT approach exposed major problems in the conduct of the water sector, including a lack of communication among organizations, the ill-defined distribution of responsibility, unclear and conflicting guidance, and insufficient funds and technological solutions, all hindering the possibility of adopting an integrative solution. This study demonstrates the role that DT plays in understanding a complex, multi-organizational problem space, in our case, the climate change readiness of the water sector, before delving into technological development. Any solution development should involve participants from the various organizations involved in the challenge. It is vital to address not only each organization’s requirements but also its technology adoption barriers and to initiate a comprehensive discussion, ultimately resulting in a shared understanding of all the facets of the challenge that can impact solution development and deployment.

Water Quality Assessment and Prevalence of Waterborne Diseases within Chikun Local Government Area, Kaduna State-Nigeria

Study’s Excerpt Water quality and the prevalence of waterborne diseases in Chikun Local Government Area, Kaduna State, were assessed. Microbiological analyses revealed microbial, helminth and protozoan contamination in water sources while Physicochemical analyses revealed heavy metal contamination. There is a need for enhanced water treatment and community awareness for improving water safety and public health in the region. Full Abstract The health and well-being of individuals in a nation are intrinsically tied to the quality of water available for consumption. Access to high-quality water plays a vital role in supporting proper nutrition, ensuring food security, and preventing waterborne diseases. Therefore, this study was carried out to assess water quality and prevalence of waterborne diseases within Chikun Local Government Area, Kaduna State. A cross-sectional study was conducted between January and June 2024. Data were collected through the administration of questionnaires (400 respondents) and laboratory water analysis. Water samples were analyzed from various sources involving boreholes, rivers and wells through composite sampling and physicochemical and microbiological analyses. Results showed samples from Unguwan Maigero and Tricania possessed varying physicochemical properties, while water from Goningora and Nasarawa revealed high turbidity and heavy metal contamination. Chloride levels were below 500 ppm, and sulphate concentrations ranged from 10.76 to 378.3 ppm. Sodium levels ranged from 19.5 to 110 mg/l, and potassium levels exceeded the permissible limit in some samples. Total coliform counts exceeded national limits (zero coliform per 100ml of water), indicating significant microbial contamination. Parasitological analysis indicated helminths and protozoan contamination in non-borehole sources. Findings showed 41% prevalence of waterborne diseases with diarrhea and typhoid. The study indicates that community awareness, appropriate water treatment, surveillance, and monitoring are essentials for assuring the availability and utilisation of safe and high-quality drinking water in Chikun LGA, Kaduna State.

Characteristics and genesis of high-quality metasilicate mineral water in Liaocheng City, Shandong Province.

Drinking natural mineral water often contains minerals and trace elements essential for human beings, such as strontium and silicon. As people's quality of life improves, so do their requirements for drinking water. Therefore, it is crucial to identify and develop high-quality groundwater that is rich in metasilicate and other minerals. The aim of this study is to reveal the distribution pattern and causes of high-quality metasilicate-rich groundwater in Liaocheng City through scientific methods, so as to provide a theoretical basis for the rational development and protection of mineral water resources. The results shown that Dong'e County was the main concentration area of high-quality metasilicate mineral water in Liaocheng City. The main reason for its high concentration of metasilicic acid was due to water-rock interaction. There was bedrock fissure water in the underlying water supply rock groups in Dong'e County, and the reaction between the metasilicate minerals in the rock groups and water was the main source of metasilicic acid. In addition, the development of fissures in the area provided a good storage and conductivity system for the enrichment of metasilicic acid in groundwater. Based on the analysis of hydrogeological conditions and the mechanism of formation of enriched areas, the enriched areas were divided into developable areas, protected and restricted development areas, and restricted development areas. The results of the study can lay a theoretical foundation for the systematic and scientific development, utilization, and protection of high-quality metasilicate mineral water in Liaocheng City.