River Water Quality Research Articles

Evaluation of the Water Quality of Nakdong River Using the Real-time Water Quality Index

Recently, the influx of pollutants into rivers has increased owing to the impacts of climate and environmental change, consequently accelerating the pollution of river ecosystems and aquatic habitats. Consequently, river water quality must be precisely assessed to facilitate effective management strategies by discerning different aspects of water quality deterioration and enhancement and by identifying and regulating river contaminants. Understanding water quality at a cursory glance is highly challenging, particularly for individuals lacking expertise in water pollution assessment. Hence, the present investigation utilized a domestically developed real-time water quality index (RT-WQI) to scrutinize the water quality attributes at 12 specific locations within the total pollution quantity monitoring network situated in the main channel of the Nakdong River system to render the water quality of the river easily comprehensible even to non-specialists. Furthermore, an attempt was made to detect patterns by applying the Mann–Kendall test and locally weighted scatter plot smoothing (LOWESS) using the index values for water quality assessment. To achieve this aim, extensive water quality data (averaged on a monthly basis) spanning 2004–2022 were obtained from the Water Environment Information System of the Ministry of Environment (https://water.nier.go.kr). The gathered date were then subjected to computation of descriptive statistics for individual water quality parameters to delineate the distinctive features of water quality. This study anticipates that the evaluation of water quality across diverse river systems in the future will facilitate the identification of highly polluted rivers and confirm their trends, thereby providing fundamental data for the management of river basins and the formulation of water quality policies.

Macroinvertebrate Community as Bioindicator of Water Quality of Tambis River, Palompon, Leyte, Philippines

Macroinvertebrates have been used globally as bioindicators of water quality of rivers due to their varying tolerance to pollution. The water quality of Tambis River in Palompon, Leyte, Philippines was determined using macroinvertebrates and selected physico-chemical and ecological assessments. Employing kick-sampling method, three sampling stations were established based on the surrounding land use (forested, agricultural, and near residential). Twenty-seven macroinvertebrate families were identified. Permutational multivariate analysis of variance (PERMANOVA) revealed a significant difference in the benthic macroinvertebrate families across three stations (p=0.001). There was a decrease in the abundance of pollution-sensitive families from the forested station towards the downstream, closest to the residential area. Sensitive Ephemerellidae and tolerant Thiaridae were the most abundant in the forested and downstream area respectively. The highest diversity and evenness were observed from the agricultural area. Stream Invertebrate Grade Number - Average Level (SIGNAL 2) scores were plotted declined in all quadrants, suggesting good water quality to moderately polluted. Water temperature, pH, and velocity were the most influencing environmental variables to the macroinvertebrate assemblage as revealed by the Canonical Correspondence Analysis (CCA). Overall, the water quality of Tambis River ranged from being of good quality to moderately polluted. The data obtained in this study could serve as a baseline in providing information to formulate and implement scientific-based regulatory measures towards the conservation of Tambis River.

THE CURRENT STATE OF THE ERTIS RIVER UNDER THE CONDITIONS OF ANTHROPOGENIC IMPACT

The article discusses the problems of pollution of the Ertis River in the Kazakhstani part of the basin. The data on the quality of river water obtained in the period from 2012 to 2023, which is generally characterized as unsatisfactory, was analyzed. The main sources of river pollution are discharges of industrial and municipal wastewater in the Bukhtarma, Ulba, Ertis river basins, and there is also a trans-boundary impact. As a result of the activities of a number of industrial complexes in the studied area, increased concentrations of heavy metals (lead, copper, zinc, and cadmium), nutrients (iron), and suspended particles (11.9–28.3 mg/dm3) are observed in the water of the Ertis River. The most polluted sections of the river are in the areas of Ust-Kamenogorsk, Semipalatinsk and Pavlodar. To improve the water quality of the Ertis River, it is necessary to take measures to reduce trans-boundary discharges of pollutants, ensure effective treatment of industrial and municipal wastewater, and also monitor the quality of the river’s water in order to track the dynamics of pollution and take timely measures to reduce it.

Pengaruh Cangkang Pomacea canaliculata L Terhadap Sifat Fisika dan Kimia Air Sungai Cisadane

The Cisadane River is a very important ecosystem for the people of the city of Tangerang. Its utilization has the potential to produce waste that can damage aquatic life so that it becomes one of the sources of the problem of decreasing water quality both physically and chemically. One of the efforts made to overcome the problem of Cisadane river water is to use water purifiers derived from natural materials so that they do not endanger health and can bind heavy metals. The purpose of this study was to determine the effect of adding snail shells to the water quality of the Cisadane river in industrial areas, urban areas and slums in terms pH value, TDS value and Pb heavy metal. The experimental procedures in this study were snail shell preparation, Cisadane river water sampling, sample analysis before application, snail shell powder application, and sample analysis after application. The results of analys show that the clarity level of Cisadane river water ranges from 19 NTU to 59 NTU, the pH value ranges from 7.2 to 7.9, the TDS value ranges from 60 mg/l to 170 mg/l and the heavy metal content is 0.0047 mg /l. The conclusion of this research is that there is an increase in the level of clarity with the addition of snail shells by 45%, there is not visible effect of the snail shells addition’s on the pH value and content of Pb heavy metal. And there is an increase in the TDS value after adding snail shells.

Editorial: Pollution and environmental water quality of river and streams

Editorial: Pollution and environmental water quality of river and streams

Mitigating the adverse impacts of climate change on river water quality through adaptation strategies: A Case Study of the Ardak Catchment, Northeast Iran

Mitigating the adverse impacts of climate change on river water quality through adaptation strategies: A Case Study of the Ardak Catchment, Northeast Iran

Anomaly detection method for urban river water quality based on background model prediction using three-dimensional fluorescence

Abstract Three-dimensional fluorescence spectroscopy has great potential for detecting water quality anomalies in urban rivers and protecting against organic pollution. However, current detection methods inadequately address critical application scenarios, such as fluctuations in river water background, low concentration of pollutants, and the fluorescence peaks overlap between pollutants and background. In this paper, a fluorescence spectrum feature extraction method which is effective for the above scenarios was proposed. The proposed method involves a sequential process. First, the original spectrum undergoes preprocessing using a novel method. Next, an alternating residual tri-linearization technique is applied to establish a predictive model for river water spectrum changes. Subsequently, the background model is utilized for spectrum decomposition and reconstruction of the test sample. This reconstructed spectrum is then used to derive the residual spectrum by comparison with the original. Finally, frequency domain features are extracted from the residual spectrum to enable classification, while the background model undergoes real-time updates. In the three meaningful scenarios mentioned above, the accuracy of the proposed method for anomaly detection reached 99%, 82%, and 98%, respectively. Our accuracy is higher than several typical benchmark methods.

Impact of Sewage Discharge on The Community Structure and Gonad Maturity of Fish in The Way Awi River Bandar Lampung

Water pollution refers to the introduction of living organisms, substances, or other components by human activities that can degrade water quality or cause environmental harm. Gonad maturity level indicates the stage of readiness of prospective broodstock for the spawning process, assessed through visual and histological methods. This study aimed to assess water quality in the Way Awi River based on fish community structure and to evaluate the impact of sewage discharge on fish gonad maturity levels in Bandar Lampung's Way Awi River. Conducted between November and December 2023, this research sampled five points along the Way Awi River. Chemical analysis included pH, BOD, COD, and DO, while physical parameters such as temperature and TSS (Total Suspended Solids) were also analyzed. The findings indicate that the Way Awi River is moderately polluted, with no significant impact on the community structure, although there is a noticeable decrease in fish numbers from upstream to downstream. This study underscores the importance of understanding the risks associated with continuous disposal of waste into rivers.

Long-Term Stability of Low-Cost IoT System for Monitoring Water Quality in Urban Rivers

Monitoring water quality in urban rivers is crucial for water resource management since point and non-point source pollution remain a major challenge. However, traditional water quality monitoring methods are costly and limited in frequency and spatial coverage. To optimize the monitoring, techniques such as modeling have been proposed. These methods rely on networks of low-cost multiprobes integrated with IoT networks to offer continuous real-time monitoring, with sufficient spatial coverage. But challenges persist in terms of data quality. Here, we propose a framework to verify the reliability and stability of low-cost sensors, focusing on the implementation of multiparameter probes embedding six sensors. Various tests have been developed to validate these sensors. First of all, a calibration check was carried out, indicating good accuracy. We then analyzed the influence of temperature. This revealed that for the conductivity and the oxygen sensors, a temperature compensation was required, and correction coefficients were identified. Temporal stability was verified in the laboratory and in the field (from 3 h to 3 months), which helped identify the frequency of maintenance procedures. To compensate for the sensor drift, weekly calibration and cleaning were required. This paper also explores the feasibility of LoRa technology for real-time data retrieval. However, with the LoRa gateways tested, the communication distance with the sensing device did not exceed 200 m. Based on these results, we propose a validation method to verify and to assure the performance of the low-cost sensors for water quality monitoring.

Accelerated urban river water quality assessment in Southern India using visible and near-infrared spectroradiometry

Optical indicators of water quality offer resource managers a swift and cost-effective means of monitoring water bodies. Remote sensing presents a promising avenue to overcome limitations, enabling comprehensive evaluation across geographical and temporal scales. This study presents initial findings utilizing hyperspectral sensing to analyze the water quality of the urban river Cooum in Chennai, Tamil Nadu. Lab analysis of 40 water samples included examination for key ions such as chloride, calcium, fluoride, sulphate, nitrate, and bicarbonates, as well as assessment of solids and colloidal components. Spectral analysis using a handheld Visible Near-Infrared (VNIR) spectroradiometer yielded reflectance curves, depicting the response of various water types and pollutants at different wavelengths. Integration of spectroradiometer data with water quality parameters facilitated the identification of empirical models tailored to the parameters of interest. The developed models exhibited an average R2 value of 0.7, underscoring the efficacy of hyperspectral remote sensing in rapidly assessing water quality in polluted rivers.

Public Perception and Knowledge of River Water Quality in Batu Pahat, Johor

The responsibility for river quality lies with government agencies. However, the success of maintaining river quality does not only rely on government agencies; it needs support from all parties, especially from the public. Thus, this study evaluated the public perceptions and knowledge of river water quality in rural areas, namely, Batu Pahat, Johor. Even though the location of this study is in a rural area, Batu Pahat’s river also suffers from pollution problems based on findings from previous studies. The set of questionnaires was formed and distributed to 506 respondents, which were selected through random sampling. The researchers filled in survey forms during face-to-face interactions with the respondents. Based on the responses, the residents had negative experiences with river water, such as bad smell and colour, suspended solid waste and failure of aquatic life due to river pollution. Due to the place of the respondents live, residents feel they need responsibility for taking care of their river water quality. They are willing to join and donate to support the programme or campaign to increase the river water quality. Residents’ basic knowledge and awareness of river water quality was moderate based on a simple quiz that was tested on them. It is recommended to conduct a program or campaign that can increase the resident’s awareness of river water quality and the impact of the program can be seen in the future.

Public Perception and Knowledge of River Water Quality in Batu Pahat, Johor.

Public Perception and Knowledge of River Water Quality in Batu Pahat, Johor.

Temporal and spatial variation in water quality in the Son La hydropower Reservoir, Northwestern Vietnam

The Son La hydropower reservoir (S.L.R.) is the largest water reservoir in Vietnam. Da River water has been treated for drinking and domestic purposes; water quality management is essential for the safety of ecosystems and human health. This study was conducted to determine changes in water quality indicators [pH, dissolved Oxygen (D.O.), total suspended solids (T.S.S.), chemical oxygen demand (C.O.D.), ammonium (NH4+), nitrite (NO2-), and coliform] in the Da River in 2010 and the Son La hydropower reservoir during 2014-2023. The results of mean annual values of Da river water quality and Son La hydropower reservoir were, specifically: pH (7.8; 7.4), D.O. (4.3; 6.2), T.S.S. (112; 5), C.O.D. (15; 8.7), NH4+ (0.17; 0.3), NO2- (0.009; 0.04), and coliform (1,723; 747). Water quality parameters significantly varied between rive and reservoir water: D.O., T.S.S., C.O.D., and Coliform. pH, T.S.S., and C.O.D. slightly decreased; however, Dissolved oxygen (D.O.), NH4+, NO2-, and coliform demonstrated an increasing trend during 2014-2023. The impact of the Son La Dam (S.L.D.) on water quality was relatively straightforward: increasing the concentration of dissolved oxygen and the self-cleaning ability of pollutants. Periodic water impoundment was divided (April to August) into a low water level of 175 m, impoundment (January to March), a median water level of 190m, and a high water level of 215 m (September to December) to period. However, the impact of the staged impoundment on water quality, especially in 2014-2023, remains unclear, except D.O., T.S.S., NH4+, NO2- and Coliform exceeded limits or were lower is not significant for living water under the Vietnam regulation, specifically: D.O. (5.36, 5.52; ≥ 6), T.S.S. (25.13; ≤ 25), NH4+ (0.3331; 0.3), NO2- (0.0504; 0.05), coliform (1,018.5; ≤ 1,000). Results from the current study provide valuable information for reservoir and river water pollution source management and reduce potential risks to exposed ecosystems, livelihoods, and human health.

Effect of Integrated Landscape Characteristics Around Chaohu Lake on River Water Quality Based on Watershed Units

Considering the impact of differences in watershed characteristics on river water quality, with the Chaohu Lake Basin as the research object, based on the data of water quality, meteorology, topography, soil, and remote sensing images of the river monitoring points from October 2019 to September 2020, the watershed unit at each monitoring point was divided through digital terrain analysis, and the comprehensive landscape characteristics based on the watershed unit were explored through the comprehensive use of correlation analysis, redundancy analysis, and multiple regression analysis to investigate the influence of comprehensive landscape characteristics based on watershed units (including land use, climate, topography, soil, etc.) on the water quality of rivers around Chaohu Lake. The results showed that:① the water quality of rivers around Chaohu Lake had large spatial differences, with the main pollutants being total nitrogen and ammonia nitrogen. Most of the rivers had total nitrogen concentrations exceeding the Class V water quality standards, and the areas with serious nitrogen and phosphorus pollution were concentrated in the urban area of Hefei and the surrounding rivers, as well as in the middle and lower reaches of the Fengle and Hangbu Rivers. ② The comprehensive landscape characteristics of the watershed unit had a significant impact on the river water quality. Among them, the proportion of built-up land, the density of patches, the dispersion and juxtaposition index, and the Shannon diversity index were positively correlated with the water quality indicators, whereas the proportion of forest and grassland and the spreading index were negatively correlated with the water quality indicators. ③ In different seasons, the effect of the integrated landscape characteristics of the watershed unit on river water quality was stronger in the wet season than in the dry season, which was mainly caused by the difference in precipitation in the dry and wet seasons.

Adsorption of Residual Pesticide Glyphosate Isopropylamine in Surface Water by Modified Biomass Materials

Effective treatment of pesticide residue-induced pollution in the aqueous environment is the key to improving the water quality of rivers and lakes. Modified biomass material (Fe-Al-PS) was successfully prepared by impregnating Fe and Al bimetallic compounds to peanut shell powder for adsorption of glyphosate isopropylamine salt herbicide residues in aqueous environments. Fe-Al-PS reached adsorption equilibrium for 10 mg·L-1 of glyphosate isopropylamine salt at the adsorbent dosage and adsorption time of 0.14 g and 10 min, respectively, and the removal rates were stabilized at 99.9 % and 99.6 %, respectively. The adsorption process followed the pseudo-secondary kinetic and Freundlich adsorption isotherm models and belonged to multi-molecular layer chemisorption. The removal of glyphosate isopropylamine salt by Fe-Al-PS was greater than 95 % in a wide range of pH (2-11). The thermodynamic results indicated that the adsorption was a spontaneous exothermic process. Fe-Al-PS materials were easy to access and involved simple synthesis and low energy consumption, had high anti-interference ability, were reusable, and could be used not only for the effective removal of glyphosate isopropylamine salt herbicide in real water bodies but also for the removal of inorganic phosphorus.

Analisis Pengaruh Musim Penghujan Dan Musim Kemarau Terhadap Kualitas Wilayah Sungai Brantas

The Brantas River is a large river in East Java that has an important role for the community. Seasonal changes have an impact on the quality of the Brantas River in Indonesia. Testing is conducted by comparing samples taken twice a year, representing the dry and rainy seasons. The river's quality is analyzed based on several parameters such as Dissolved Oxygen (DO), BOD, COD, NO3-N, and Phosphate. The results are then compared with the standard river quality according to Government Regulation No. 22 of 2021. The analysis results indicate that the season has a significant impact on the river water quality, as seen from the different parameters in each season.

Persistent organic pollutants in sediment of a tropical river: the case of N’djili River in Kinshasa (Democratic Republic of the Congo)

Surface sediments collected in several areas along the N’djili River, in the Kinshasa Province, Democratic Republic of the Congo, were analyzed for persistent organic pollutants (POPs), including polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), organochlorine, polycyclic aromatic hydrocarbons (PAHs), and also organophosphorus and pyrethroid (PYR) pesticides. High values of POPs were determined in the DIGUE area of the river reaching 710 µg kg−1 for ∑12 PCBs, 397 µg kg−1 for ∑6 DDTs, 1138 µg kg−1 for ∑16 PAHs, and 23 µg kg−1 for ∑6 PBDEs. Regarding toxic effects on aquatic biota, the Total PCBs (∑7 × 4.3) were above the Threshold Effect Level (TEL) value of 34.1 μg kg−1 and above the Probable Effect Level (PEL) value of 277 μg kg−1 in most sampling sites. ∑16 PAHs values were, in general, below the TEL value of 610 μg kg−1, but with exceptions for several sampling sites where values exceeded the TEL value. The ∑6 DDTs in all sampling sites were higher than both TEL and PEL values of 6.15 and 20.03 μg kg−1, respectively. These values above TEL and PEL indicate potential adverse effects on benthic organisms. In general, the ratio values of (DDD + DDE)/DDT were higher than 0.5 reflecting past DDT use mostly, and Fluo/(Fluo + Pyr), IDP/(IDP + BghiP) and BaA/(BaA + Chry) ratios indicated several PAHs origins including petrogenic and pyrolytic sources, petroleum, grass, wood and coal combustion. Globally, the results of this research showed high contamination of N´djili River sediments by a plethora of organic pollutants and at toxic levels to the aquatic biota. Furthermore, the river water quality might be not suitable for human consumption.

Improving river water quality prediction with hybrid machine learning and temporal analysis

River systems provide multiple ecosystem services to society globally, but these are already degraded or threatened in many areas of the world due to water quality issues linked to diffuse and point-source pollutant inputs. Water quality evaluation is essential to develop remediation and management strategies. Computational tools such as machine learning based predictive models have been developed to improve monitoring network capabilities. The model's performance is reduced when datasets composed of reductant information are used for training, on the other hand, the selection of most representative and variable water quality scenarios could result in higher precision. This study analyzed historical water quality behavior in the Santiago River, Mexico, to identify the most variable and representative data available to train machine learning models (Adaptive Neuro Fuzzy Inference System – ANFIS, Artificial Neural Network – ANN, and Support Vector Machine - SVM). Thirteen monitoring sites were clustered according to their water quality variability from 2009 to 2022. Subsequently, a Time Series Analysis (TSA) was used to select the most representative monitoring station from each cluster. Data for 6/13 monitoring sites were retained for the Best Training Subset (BTS) used to train restricted models that performed with similar (ANN and SMV) or higher (ANFIS) prediction accuracy (in terms of RMSE, MAE, MSE and R2) for both training and testing. This study provides evidence of water quality data containing redundant information that is not useful to improve machine learning model performance, in turn leading to overtraining. Combined analytical approaches can maximize the representativeness and variability of data selected for machine learning applications, leading to improved prediction.

Evaluation of the Effect of Agricultural Return Flow on Water Quality, Water Quantity and Aquatic Ecology in Downstream Rivers

Agricultural water serves various functions, including public interest purposes, beyond its primary role in agricultural production. In order to evaluate the various public interest purposes of agricultural water, a quantified study of the effect of agricultural water on river flow, water quality, and aquatic ecosystems is needed. Therefore, this study quantified the impact of agricultural water on the environmental and ecological maintenance function of downstream rivers, taking into account the return flow of agricultural water in rural areas. To this end, first, the effect of agricultural return flow on river maintenance function was evaluated by comparing the return flow quantity calculated using the reservoir supply data with the simulated river flow rate through the SWAT model. Second, the effect of the agricultural return flow on the downstream river environmental ecological function was analyzed using the optimal flow rate results calculated through the PHABSIM model. The lastly, the effect of agricultural water by farming period on the water quality of downstream rivers was analyzed. As a result of the analysis, it was found that the return flow of agricultural water had a large effect on the river flow rate in the case of the non-rainy season, but the optimal ecological flow rate was not satisfied. In the case of river water quality, it was confirmed that the effect of agricultural water (mainly considered as a pollutant) was not significant, except for the drainage duration of rice paddies. Therefore, it can be understood that agricultural water is not only used for the purpose of production but can also have a positive impact on the aquatic ecology of downstream rivers.

Environmental effects of river ice, The Saint John (Wolastoq) River, New Brunswick, Canada

ABSTRACT The Saint John (Wolastoq) River (SJR) is a major international river flowing through the State of Maine, USA, and the Province of New Brunswick, Canada. In terms of river length and basin area, it is one of the largest rivers on the eastern seaboard of North America south of the St. Lawrence River system. Subject to seasonal ice cover, ice conditions vary along the SJR due to natural differences in climate and terrain, and due to anthropogenetic changes, such as the construction of dams. Ice formation, growth, and breakup along the SJR affects its hydraulic and ecological regimes and leads to the potential for ice jamming that has caused severe flooding and ice runs. Ice affects river erosion, flooding, ecology, water quality, and recreational uses of the SJR. An overview of typical winter climate and ice season characteristics along the SJR from Dickey, Maine, USA to Saint John, New Brunswick, and some of its environmental consequences are summarized in this review paper. Ice processes and phenomena that occur along the SJR occur along other northern rivers, and can cause similar environmental concerns and consequences that should not be ignored in river engineering and basin management.