Water Quality Assessment Research Articles

What is the Difference between Conventional Drinking Water, Potable Reuse Water, and Nonpotable Reuse Water? A Microbiome Perspective.

As water reuse applications expand, there is a need for more comprehensive means to assess water quality. Microbiome analysis could provide the ability to supplement fecal indicators and pathogen profiling toward defining a "healthy" drinking water microbiota while also providing insight into the impact of treatment and distribution. Here, we utilized 16S rRNA gene amplicon sequencing to identify signature features in the composition of microbiota across a wide spectrum of water types (potable conventional, potable reuse, and nonpotable reuse). A clear distinction was found in the composition of microbiota as a function of intended water use (e.g., potable vs nonpotable) across a very broad range of U.S. water systems at both the point of compliance (Betadisper p > 0.01; ANOSIM p < 0.01, r-stat = 0.71) and point of use (Betadisper p > 0.01; ANOSIM p < 0.01, r-stat = 0.41). Core and discriminatory analysis further served in identifying distinct differences between potable and nonpotable water microbiomes. Taxa were identified at both the phylum (Desulfobacterota, Patescibacteria, and Myxococcota) and genus (Aeromonas and NS11.12_marine_group) levels that effectively discriminated between potable and nonpotable waters, with the most discriminatory taxa being core/abundant in nonpotable waters (with few exceptions, such as Ralstonia being abundant in potable conventional waters). The approach and findings open the door to the possibility of microbial community signature profiling as a water quality monitoring approach for assessing efficacy of treatments and suitability of water for intended use/reuse application.

Perceptions and knowledge about the use of biological indicators in freshwater ecosystem monitoring in Rwanda

The use of biological monitoring (biomonitoring) to assess water quality is recognised alongside the use of chemical and physicochemical parameters due to its ability and efficiency in providing information about both current and long-term changes. Indeed, biomonitoring is applied in several developed and developing countries. Nevertheless, some developing countries, such as Rwanda, are yet to adopt such a monitoring system. This paper presents results of an assessment of the knowledge and perceptions by water resource managers about the use of biomonitoring and bioindicators, and challenges to their integration into existing routine water quality monitoring systems in Rwanda. Qualitative research, using semistructured interviews, was conducted with nine water resource practitioners from six water governance institutions between August and November 2021. The results show that participants are aware that macroinvertebrates, algae and fish are bioindicators that have potential applications in Rwanda to complement the chemical and physicochemical parameters already being collected in the country’s water monitoring system. The main challenges for integration of biological indicators, as indicated by participants, include the need for equipment, funding, technical skills and taxonomic knowledge. Training in the use of bioindicators and taxonomy are needed to raise the awareness and skills of staff from the institutions involved in freshwater ecosystem management in Rwanda, and to encourage integration of biomonitoring results into national water monitoring frameworks.

Assessment of water quality and identification of priority areas for intervention in Guanabara Bay basin, Rio de Janeiro, Brazil, using nonparametric and multivariate statistical methods.

The Guanabara Bay hydrographic region (GBHR) has served as a central hub for human settlement and resource utilization throughout Brazil's history. However, the region's high population density and intense industrial activity have come at a cost, leading to a significant decline in water quality. This work aimed to identify homogeneous regions in GBHR according to water quality parameters in dry and rainy periods. The following water quality monitoring variables were monitored at 49 gauge stations: total phosphorus (TP), nitrate (NO3-), dissolved oxygen (DO), hydrogenionic potential (pH), turbidity (Turb), thermotolerant coliforms (TCol), total dissolved solids (TDS), biochemical oxygen demand (BOD), water temperature (Tw), and air temperature (Ta). The statistical analysis consisted of determining principal components, cluster analysis, seasonal differences, and Spearman's correlation. The water quality parameter correlations were not expressively influenced by seasonality, but there are differences in the concentrations of these parameters in the dry and rainy periods. In the dry period, urban pressure on water quality is mainly due to fecal coliforms. The resulting clusters delimited areas under urban, agricultural, and forestry influence. Clusters located in areas with high demographic density showed high concentrations of TCol and TP, while clusters influenced by forestry and agriculture had better water quality. In the rainy season, clusters with urban influence showed problems with TCol and TP, in addition to some characteristics in each group, such as high TDS, NO3-, and BOD. Forested areas showed high DO, and clusters under agricultural influence had higher concentrations of TCol, BOD, and NO3- concerning forested regions. The troubling state of sanitation in GBHR occurs in metropolitan regions due to lack of a formal sanitation system.

An Assessment of Water Quality and Identification of Problems: A Case Study of Maritimepattu Divisional Secretariat, Northern Province

An Assessment of Water Quality and Identification of Problems: A Case Study of Maritimepattu Divisional Secretariat, Northern Province

Long-term observations of the turbid outflow plume from the Russian River, California

Understanding the mechanisms that spread freshwater away from small river systems and form turbid, low-salinity coastal plumes is crucial for assessing water quality in coastal waters. We present an analysis of 15 years (January 2004 to December 2018) of daily MODIS Aqua satellite data and in situ instrument data on the turbid freshwater plume that forms off the Russian River (California, USA), a prototypical Mediterranean-climate, small mountainous river system (SMRS). We present per-pixel statistical metrics and regression analyses to identify and quantify the controls on the extent and configuration of the plume exerted by river discharge, waves, winds, and tides. While freshwater outflow exhibits a persistent signal in nearshore waters, a large-scale plume only extends offshore into coastal waters during high river flow, when plume turbidity can be detected more than 10 km offshore from the river mouth. Our results show times when wave radiation stress exceeds outflow inertia, confining the plume within the surf zone and leading to an absence of detectable plume turbidity in coastal waters. Although tidal currents significantly influence the plume near the inlet, wind forcing is the primary control on plume shape and extent in coastal waters, deflecting the turbid outflow more than 30 km upcoast or downcoast of the river mouth with respective wind directions. Coriolis forcing is also significant and observed most clearly during periods of high river discharge and low wind forcing. In addition to introducing novel remote sensing methodology for SMRS plume analyses, these findings highlight the complex interplay of forcing related to tides, river discharge, winds, and waves in shaping the behavior of SMRS plumes. New insights include the impact of tides on larger discharges, the role of Coriolis forcing in SMRS plumes, and the effect of cross-shore winds on plume compression. Further, by considering the Russian River as a model for SMRS, this study can be used to ground-truth existing numerical models of small river plumes and to contribute to understanding critical for managing coastal water quality and nearshore ecosystems.

Assessing water quality of kazerun county in southwest Iran: Multi-analytical techniques, deterministic vs. probabilistic water quality index, geospatial analysis, fuzzy C-means clustering, and machine learning

Water quality is critical to human health and the environment, especially in arid and semi-arid regions. Hence, the objectives of this study were to assess drinking water quality, identify critical parameters, investigate spatial patterns, and investigate accurate predictive models for the water quality index (WQI) in the Kazerun county in southwest Iran. To address this issue using deterministic and probabilistic WQI, correlation matrix, fuzzy C-Means (FCM) clustering, geostatistics, and adaptive network-based fuzzy inference system (ANFIS) with FIS generation by fuzzy C-Means (FCM-ANFIS) and sub-clustering (SC-ANFIS).Various software tools, including Excel, MATLAB, Python, and GIS were used to analyze groundwater data collected from 25 sampling sites. Water parameters, including pH, Cl−, SO4−2, EC, NO3−, NO2−, Ca2+, Mg2+, and F−, were examined. The results showed that F− levels were within acceptable limits set by the US EPA, but about one-third of sites posed potential health risks based on WHO guidelines. In one-third of regions, the levels of Mg2+ exceeded the recommended guidelines. In deterministic and probabilistic approaches, water quality was excellent in 68% and 81.3% of sites, respectively. Sobol sensitivity analysis identified SO4−2> Mg2+>Cl− > EC > F− > NO3− as significant WQI variables. Spearman correlation matrix shows substantial positive correlations between WQI and EC, F−, SO4−2, Mg2+, and Cl− were shown by the Spearman correlation matrix. Based on the FCM results, the southeast and central sites (56% of sites) have similar water quality. In comparison, the northern and four central sites (28% of sites) have distinct regional features, and the southern sites (16% of sites) had unique water quality characteristics. Geostatistical analyses showed that pH had the most substantial local clustering, while SO4−2 had significant high-value clustering. Furthermore, hot spot research revealed specific sites with high pH, F−, NO3−, and Cl− levels. The FCM-ANFIS model outperformed the SC-ANFIS model, emphasizing FCM clustering's importance in water quality forecasting accuracy.

The Application of the Game-Gray Target Model on the Water Quality Assessment in the Tao Jiang River

The Application of the Game-Gray Target Model on the Water Quality Assessment in the Tao Jiang River

Plankton and contour algal communities in the Ukrainian section of the Western Bug River and its tributaries

The paper deals with spatial dynamics of cell count, biomass, dominant species complexes, information diversity of planktonic and contour algal communities in the Western Bug River and its tributaries. The trophic state and water quality of the rivers under study have been assessed. The spatial heterogeneity of phytoplankton, microphytobenthos and phytoperiphyton brought about high cell count and biomass values during the low-water summer-autumn season. The cell count and biomass have been shown to increase from the upper reaches downstream, correlating with the river bed width. High quantitative diversity of algal communities was due to Bacillariophyta dominance. Cyanobacteria and Chlorophyta were recorded as subdominants. The trophic state of the aquatic ecosystems under study varied between oligotrophic and eutrophic. The Shannon’s index made up 1.58–4.62 bit/cell and 1.60–4.40 bit/mg. The trophic state and information diversity assessed according to contour algal communities were higher than according to phytoplankton. This is indicative of the clear water regime forming in the rivers under study during the low-water summer-autumn season. The obtained findings differ from the data, published earlier for the Kaniv Water Reservoir, where the primary role belonged to phytoplankton. The spatial heterogeneity of algal communities is related to the dominant complexes structure. As a rule, these are monodominant Bacillariophyta complexes or oligodominant Bacillariophyta – Cyanobacteria or Bacillariophyta – Chlorophyta complexes. The water quality assessment according to the abiotic variables and saprobiologic characteristics has shown that the modal classes of water quality are the 2nd–3rd classes (clean waters – satisfactory clean waters). Therefore, the water quality of the Ukrainian section of the Western Bug River and its tributaries does not pose any substantial hazard to the adjacent European countries.

Ecological Structure of Macrobenthic Invertebrates of the Benin River, Southern Nigeria, Before the Seaport Development Project

Macrobenthic invertebrates are major components of aquatic ecosystems. Because of their partial or sessile motion, they can be used to assess water quality status. The Benin River is a beehive of human activity, and with the development of the proposed seaport along its course, its physical, chemical, and biological components may be affected. The need to document macrobenthic invertebrates before the seaport development prompted this study. Four stations were selected between Ajoki and a section opposite Young Town, employing both kick sampling and Ekman grab techniques. Seasonal influence on the distribution and abundance of macrobenthic invertebrates was observed. In total, 3,267 macrobenthic invertebrates were collected during the sampling period. The highest number of taxa (35) were recorded in Station 1, and the highest number of individuals (1,103) was in Station 3. The dominant macrobenthic invertebrate group was Decapoda (76.61%); Diptera (6.15%) and Ephemeroptera (4.62%), others constituted the remaining 12.62%. There was a positive correlation between the family Diaptomidae and the physicochemical parameters, except for heavy metals.

Water Quality Assessment and its Impact on Shrimp in the Rupnarayan River: A Comparative Study from February to May of 2022-2024

The Rupnarayan River is the heart of the Purba Medinipur district of West Bengal, as it is the habitat of a large number of aquatic species and the main drinking, agricultural, irrigation, and cultivation resource. We collected river water samples from the Kolaghat, Alinan, Siuri and Deemari villages near Tamluk in the Purba Medinipur district. Then, we assessed different water quality parameters, such as temperature, turbidity, pH, DO, BOD, salinity, alkalinity, and hardness. We studied the premonsoon phase (Feb-May) and assessed the impact of these parameters on the production of shrimp species. We identified M. rosenbergi, M. brevicornis, M. monoceros, and Penaeus vannamei as shrimp species. We also compared the data from 2022 to 2024 (Feb-May) and observed yields of 40%, 60%, and 30% in 2022, 2023 and 2024, respectively.

Water Quality Evaluation and Spatial-temporal Distribution Characteristics of the East Route of the South-to-North Water Diversion Project in Jiangsu Province Based on WQI

The east route of the South-to-North Water Diversion Project in Jiangsu Province was used as an example to investigate the characteristics of changes in water quality in the area affected by significant water diversion projects. Based on the comprehensive assessment method of the water quality index （WQI）, the M-K trend test, and the geographic information system （GIS）, the spatial and temporal variation characteristics of water quality in the 13 national assessment sections of the east route of the South-to-North Water Diversion Project in Jiangsu Province were evaluated and analyzed from 2013 to 2022. The results showed that the water quality assessment grades in the study area were mainly "medium" and "good." The overall mean value was 74.03, indicating "good" water quality. DO, BOD5, and NH4+-N were the primary indicators of changes in river water quality in the region. Over time, the water quality in the basin had significantly improved from 2013 to 2022. However, there was a rebound in 2021, but this phenomenon was effectively controlled in 2022. Water quality was better during the non-flood season compared to that during the flood season. From a spatial perspective, the water quality in the southern part of the region was superior to that in the north. Furthermore, the rate of improvement was faster in the south. This could be attributed to factors such as precipitation, population density, and the scale of agricultural and livestock activities. However, the water quality of the S11 （Sanduoxi Bridge） section was generally lower than that of other sections and should be given further attention.

Water Quality Assessment using Machine Learning: A Focus on Coliform Prediction in Water

Water quality assessment is essential for safeguarding public health and protecting water resources. This study focused on predicting water quality, specifically the presence of total coliforms, using various machine-learning techniques. The present study utilises a publicly available dataset encompassing the geographical area of India consisting of various physical water quality parameters. Various regression techniques were applied to the dataset after appropriate pre-processing including feature selection and normalisation. The findings demonstrate that gradient boosting regression outperforms other methods, achieving high accuracy with mean absolute error (MAE) of 0.0349, mean squared error (MSE) of 0.0038, and root mean squared error (RMSE) of 0.0620. Conductivity and temperature emerged as the most influential factors in total coliform prediction, as revealed by feature importance analysis. These results contribute to water quality understanding, aiding water resource management for public health protection. By accurately predicting total coliform presence, proactive measures can be taken timely to mitigate and minimise health risks associated with microbial contamination.

Integrating GEE and IWQI for sustainable irrigation: A geospatial water quality assessment

The surface and sub-surface water quality is one of the decisive parameters for sustainable agriculture and water resources management. Deteriorating water quality impacts the irrigation, crop production, and human health. Therefore, the present work made an attempt to identify the water suitability for irrigation using the contemporary approach i.e. Irrigation Water Quality Index (IWQI) and Zone mapping using GIS techniques, and demonstrated for case of Wadhwan, Gujarat India. Three indices i.e., NDVI, NDWI, and LSWI were mapped using Landsat satellite imagery, whereas, Watermask index was mapped using Sentinel II satellite imagery for the assessment of the availability of water in different forms. The IWQI has applied to categorize the water quality as severe, high, moderate, low, and no restriction. The IWQI in the study area ranges from 6.4 to 62.5. The overall the water quality of study area shows that the 13.64 % of the region in severe restriction range, 56.82% in high restriction range, and 29.54% in moderate restriction range, which is in alarming for farmers and policy makers. The GIS zoning map effectively visualized the spatial distribution of IWQI, helping decision-makers to identify severity zones. Furthermore, the Piper diagram analysis has been performed, which shows that the water quality of the study area falls under mixed Ca2+-Mg2+-Cl-, mixed Ca2+-Na+-HCO3-, and Na-HCO3 types. The results revealed that major areas are in moderate to severe restriction zones, lying under deteriorated water quality, and need immediate attention for improvement before use. The IWQI advances SDG 2 (Zero Hunger) by optimizing water quality for crop production and SDG 6 (Clean Water and Sanitation) by ensuring sustainable water resource management, while indirectly supporting SDG 15 (Life on Land) through improved soil health and land management practices.

Systematization of a toxicity screening method based on a combination of chemical analysis and the delayed fluorescence algal growth inhibition test for use in emergency environmental surveys.

In recent years, heavy rainfall disasters linked to climate change have become more frequent, raising concerns about the release of chemicals stored in factories. Assessing chemical contamination during such emergencies therefore necessitates the development of a quick and easy method for evaluating hazardous contaminants in combination with toxicity testing. This study proposes a "toxicity screening" method that combines biological response testing and chemical analysis to systematically evaluate hazardous contaminants in emergency situations. The toxicity screening method evaluates the water quality in three steps, including water quality measurements and a delayed fluorescence (DF) assay, metal content measurements and a DF assay, and targeted screening analysis and a DF assay. The efficacy of this method was tested using industrial wastewater from 14 locations. Seven of the samples were non-toxic, while the other seven samples were toxic, displaying no observed effect concentration (NOEC) values ranging from 0.625 to 20%. Two toxic samples in the first phase possessed high total chlorine concentrations (0.4mg L-1) and conductivities (2200 mS m-1), indicating that the main sources of toxicity were residual chlorine and a high salt concentration. In the second phase, metal content analysis identified metals as the toxicity cause in four samples. In the third phase, the organic contaminants were analyzed, and tri-n-octyl phosphate (TNOP) was detected at a concentration of 0.00027mg L-1. The results of solid-phase extraction experiments and exposure tests with TNOP alone indicated that the contribution of TNOP to the toxicity was negligible and that chemicals not adsorbed on the solid-phase extraction cartridges were the cause of toxicity. The proposed method can therefore be considered effective for disaster-related water quality assessment, delivering results within 12days.

Cultivating sustainability: a multi-assessment of groundwater quality and irrigation suitability in the arid agricultural district of Dzira (Ksour Mountains, Algeria).

Groundwater serves a range of essential functions such as supplying drinking water, facilitating agricultural practices, and supporting industrial processes. This study examines with multiple methods the quality of groundwater in the agricultural region of Dzira, Algeria. By collecting 38 groundwater samples of different wells and boreholes, valuable awareness of the aptness of groundwater for irrigation in this arid landscape was gained. Most wells met Food and Agriculture Organization (FAO) criteria for the total dissolved solids (TDS) and the potential of hydrogen pH, but some areas had higher mineral content and electrical conductivity. Results show significant TDS variations, with 10.81% of wells exceeding limits and acceptable pH levels. Elevated EC values in 67.57% of wells show high salinity, affecting soil and plant growth. Major ions such as Mg2+ and SO4- exceeded FAO standards in 43.24% and 64.86% of wells, respectively, highlighting substantial mineral content in the groundwater. Suitability indices reveal that most wells pose low sodium hazards and are generally suitable for irrigation, though some areas face moderate to high restrictions. The irrigation water quality index (IWQI) ranged from 45.36 to 96.30, averaging 80.77, with 54.04% classified as "low restriction," suitable for sandy soils with good permeability but requiring caution on salt-sensitive soils. Hydrogeochemical analysis using principal component analysis (PCA) and hierarchical cluster analysis (HCA) identifies rapid evaporite dissolution from Triassic saline formations, with a correlation matrix showing associations between TDS and Ca2⁺, Mg2⁺, Na⁺, Cl⁻, and SO₄2⁻. This mineralization is likely from gypsum and halite. Zoning maps based on IWQI and other parameters depicted spatial variations in groundwater quality, guiding effective irrigation management strategies. Overall, the study underscores the importance of comprehensive water quality assessment for sustainable agriculture and emphasizes the need for targeted interventions to mitigate potential challenges associated with soil salinity and sodicity. Therefore, these findings can be useful to decision-makers and stakeholders in order to optimize water use and protect this vital resource.

Assessment of process water quality (depending on the presence of process water systems) in car wash facilities across Germany and the Netherlands

ABSTRACT There are around 2,500 car wash lines in Germany, consuming around 30 million m3 of drinking water per year. In view of the increasing scarcity of water, this level of consumption could soon be restricted by law, as it is in some countries. There are only a few systematic studies on process water systems in car wash lines in Middle Europe; we therefore carried out a survey to determine process water quality parameters (COD, turbidity, water hardness, pH, conductivity, dissolved O2, and temperature). Data were collected and analysed from 63 different locations in Germany and the Netherlands. In addition, longitudinal parameters were measured for 1 year at a single state-of-the-art site in Germany. The scatter of the observed values was quite considerable. The average COD in water of car wash sites with biological treatment was found to be significantly lower than in car wash sites working with filter treatment. Overall, the deviation of the pollution parameters was higher than expected. Surprisingly, there is hardly any reliable data on freshwater consumption in the car wash facilities. As most of the long-established facilities do not have a modern water treatment system, freshwater consumption is up to 300 L per car washed.

Human health risk and water quality assessment due to fluoride and nitrate around Cauvery River basin, southern India.

Good quality water for human consumption, irrigation, and industrial use is very important. Today, around the world, water is contaminated by natural processes and human activities. This study aimed to evaluate the suitability of groundwater for drinking and irrigation, identifythe source of fluoride and nitrate contamination, and assess thehuman health risks around the Cauvery River basin in southern India. A total of 30 groundwater samples were collected and analyzed for hydrochemical parameters, including EC, TDS, pH, Ca, Mg, Na, K, HCO3, Cl, SO4, NO3, and F-. The majority of groundwater samples in the study area are used for drinking and irrigation. The pH of groundwater in the study area was observed to be dominantly alkaline. The levels of TDS, Ca, Na, K, F, and TH exceeded the permissible limits recommended by BIS and WHO. Fluoride and nitrate levels in groundwater exceeded the permissible limits for drinking purposes in 43% and 50% of the samples, respectively. The excessive concentration of fluoride and nitrate in groundwater could pose serious human health problems. Fluoride and nitrate concentrations in groundwater vary between 0.1 and 2mg/l and 12 and 95mg/l, respectively. Based on the computation of the drinking water quality index, about 73% of groundwater samples were classified asexcellent to good. Health risk was assessed for infants, children, and adults using non-carcinogenic risk indices such as hazard quotients (HQ), hazard indexes (HI), total hazard indices (THI), and carcinogenic risk indices (CR). Infants, children, and adults have different total hazards indexes ranging from 1.508 to 5.733, 1.579 to 6.003, and 0.011 to 0.046, respectively. Health risk assessment results indicatedthat the hazard index and hazard quotient were above the recommended limit of > 1 in most of the samples for infants and children. Non-carcinogenic risk and carcinogenic risks were more likely to affect infants and children rather than adults through ingestion of contaminated water.

Water quality assessment of hydrochemical parameters and its spatial–temporal distribution: a case study of water resources in the Kebir Rhumel Basin, Algeria

Water quality assessment of hydrochemical parameters and its spatial–temporal distribution: a case study of water resources in the Kebir Rhumel Basin, Algeria

Water Quality Parameters of Sodic Soil Ponds Fertilized with Cattle Dung and Poultry Manure

A field experiment was conducted from August to November 2023 at the Instructional Fish Farm, College of Fisheries, Acharya Narendra Deva University of Agriculture &amp; Technology, Kumarganj Ayodhya, Uttar Pradesh. The study aimed to assess water quality parameters. The experimental design included fifteen earthen ponds (8m × 8m × 1m), divided into five treatments with three replicates each. The treatments were as follows: (T1) control with pond bottom soil base, (T2) pond bottom soil with cattle dung at 20 t/ha, (T3) pond bottom soil with cattle dung at 15 t/ha, (T4) pond bottom soil with poultry droppings at 10 t/ha, and (T5) pond bottom soil with poultry droppings at 7.5 t/ha. Over the 90-day experimental period each pond evaluated the effects of cattle dung andpoultry droppings on water quality parameter. Results demonstrated that the treatment with poultry droppings at 10 t/ha (T4) significantly enhanced water quality, proving to be superior to treatments with cattle dung, followed by treatment T2 (20 t/ha cattle dung).

Dynamic analysis of groundwater chemistry from 1997 to 2018 in the eastern part of Yongning County, Ningxia Hui Autonomous Region of northwestern China: Integration of Bayesian water quality assessment and health risk assessment

AbstractGroundwater is an important part of water resources, with many characteristics: widespreading, steady changing, good water quality, and usable. Therefore, it is an ideal drinking water source. However, with the rapidly economic development and the accelerated urbanization process, the problem of groundwater pollution has become increasingly serious. In this study, the eastern part of Yongning County was taken as the study area, 30 groundwater samples from 1997 to 1998, 2007 to 2008, and 2017 to 2018 were selected for water quality assessment and health risk assessment. The results showed that the groundwater chemical type had a tendency to change from HCO3‐Ca·Mg type to SO4·Cl‐Ca·Mg type, and the rock weathering was the important factor controlling the groundwater hydrochemistry in the eastern part of Yongning County. The water quality evaluation of Mn and As was grade II, and the water quality evaluation of Cu, Zn, Cr6+, Cd, and Mo was grade I. Both carcinogenic and non‐carcinogenic risks were higher in children than in adults, the acceptable frequency of adults was higher than that of children, and the area with higher risks was distributed in the central and easternmost regions of Yongning County. As was a more sensitive factor to carcinogenic risk than Cr6+. Therefore, we should pay more attention to the governance of As and the health of children's drinking water. Special attention also should be paid to the water environment protection in the eastern parts of Yongning County. Water quality assessment and health risk assessment in the study area lay a foundation for water pollution control and water environmental protection in the future.Practitioner Points The hydrochemical type changes from HCO3‐Ca·Mg type to SO4·Cl‐Ca·Mg type, which is mainly affected by rock weathering. According to the Bayesian water quality assessment: Mn and As was II, and Cr belongs to I is small. As was the main carcinogenic factor, Mn was the main non‐carcinogenic factor, and the risk was higher in children than adults.