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In response to Egypt's escalating water scarcity and pollution, Riverbank Filtration (RBF) technology is emerging as an effective solution to enhance water quality and simplify drinking water provision. This study evaluates RBF at three sites in Upper Egypt by assessing hydrogeological conditions and water quality based on 36 parameters from 2022 to 2023. Findings indicate that RBF efficiently treats infiltrated river water, with all sites meeting turbidity and microbiological standards (Total Bacterial Count and Coliforms), achieving removal rates of approximately 90% and 99%, respectively. Despite these successes, challenges persist in reducing manganese to safe levels, with concentrations at Alsaayda site reaching 0.51 mg/L, over the drinking water safe limit of 0.4 mg/L. To address this, further post-treatment strategies are proposed to remove the excess manganese. A practical application of an Oxidizer at the Bani Murr groundwater treatment plant has demonstrated the effective removal of iron and manganese, bringing their levels down to safe drinking water standards. This case exemplifies a successful solution for iron and manganese removal. This research highlights RBF's potential in water treatment in developing countries, while emphasizing the need for supplementary measures to manage specific contaminants. [ABSTRACT FROM AUTHOR]

Pharmaceuticals and personal care products (PPCPs) are found in most rivers facing sewage input worldwide. This study investigated the occurence of 116 PPCPs in the Elbe river in Dresden, Germany, as well as the removal efficiency at a riverbank filtration (RBF) site. The data obtained were compared with data from two additional surface water monitoring stations along the Elbe river operated by a state environmental agency. 21 PPCPs were frequently detected in all water samples with concentrations up to 1270 ng/L. Spatial occurrence and sociodemographic aspects are discussed. According to the European Guideline for Environmental Risk Assessment, carbamazepine, diclofenac, iomeprol and venlafaxine indicate a suspected risk for the aquatic environment but not for drinking water quality in the Dresden region. Water treatment using a combination of natural treatment techniques and post-treatment using activated carbon filtration and disinfection proved to be an efficient barrier to drinking water pollution by PPCPs.

Expanding urbanization, socioeconomic factors, and agricultural activities have led to contamination of the natural water resources in Iraq. The objective of this study was to assess the riverbank filtration (RBF) process in purifying the water of Al-Kufa River from pathogens. The riverbank filtration is a natural approach that helps in the enhancement of the quality of river water, and it is a relatively cost-effective, and sustainable process. This study utilized microbiological approaches to monitor the water quality of wells in comparison with river water. In Al-Kufa district of Al-Najaf governorate in Iraq, eight wells were constructed at different locations adjacent to Al-Kufa River. Total plate count, coliform count, fungal count, and fecal coliform count were among the microbiological parameters tested. The findings of the current study showed a difference in the pathogen count between the wells and river water, but the riverbank filtration process did not meet the World Health Organization guidelines. From this, we concluded that, if the pumping well is continuously running, RBF as a preliminary treatment of surface water would be a promising and potentially viable application in purifying water supply. Finally, in future RBF process is supposed to be taken into consideration to protect the security of water supply from waterborne pathogens.

In drinking water supply, riverbank filtration (RBF) is an efficient and cost-effective way of eliminating pathogens and micropollutants using a combination of biotic and abiotic processes. Microbial communities in the hyporheic zone both contribute to and are shaped by these processes. Microbial water quality at the point of consumption is in turn influenced by the source water microbiome, water treatment and distribution system. Understanding microbial community shifts from source to tap and the factors behind them is instrumental in maintaining safe drinking water delivery. To this end, microbial communities of an RBF-based drinking water supply system were investigated by metabarcoding in a one-year sampling campaign. Samples were collected from the river, RBF wells, treated water, and a consumer's tap. Metabarcoding data were analysed in the context of physicochemical and hydrological parameters. Microbial diversity as well as cell count decreased consistently from the surface water to the tap. While Proteobacteria were dominant throughout the water supply system, typical river water microbiome phyla Bacteroidota, Actinobacteria, and Verrucomicrobiota were replaced by Nitrospira, Patescibacteria, Chloroflexi, Acidobacteriota, Methylomicrobilota, and the archaeal phylum Nanoarcheota in well water. Well water communities were differentiated by water chemistry, in wells with high concentration groundwater derived iron, manganese, and sulphate, taxa related to iron and sulphur biogeochemical cycle were predominant, while methane oxidisers characterised the more oxic wells. Chlorine-resistant and filtration-associated taxa (Acidobacteria, Firmicutes, and Bdellovibrionota) emerged after water treatment, and no potentially pathogenic taxa were identified at the point of consumption. River discharge had a distinct impact on well water microbiome indicative of vulnerability to climate change. Low flow conditions were characterised by anaerobic heterotrophic taxa (Woesarchaeales, Aenigmarchaeales, and uncultured bacterial phyla MBNT15 and WOR-1), implying reduced efficiency in the degradation of organic substances. High flow was associated the emergence of typical surface water taxa. Better understanding of microbial diversity in RBF water supply systems contributes to preserving drinking water safety in the future changing environment. [ABSTRACT FROM AUTHOR]

Expanding urbanization, socioeconomic factors, and agricultural activities have led to contamination of the natural water resources in Iraq. The objective of this study was to assess the riverbank filtration (RBF) process in purifying the water of Al-Kufa River from pathogens. The riverbank filtration is a natural approach that helps in the enhancement of the quality of river water, and it is a relatively cost-effective, and sustainable process. This study utilized microbiological approaches to monitor the water quality of wells in comparison with river water. In Al-Kufa district of Al-Najaf governorate in Iraq, eight wells were constructed at different locations adjacent to Al-Kufa River. Total plate count, coliform count, fungal count, and fecal coliform count were among the microbiological parameters tested. The findings of the current study showed a difference in the pathogen count between the wells and river water, but the riverbank filtration process did not meet the World Health Organization guidelines. From this, we concluded that, if the pumping well is continuously running, RBF as a preliminary treatment of surface water would be a promising and potentially viable application in purifying water supply. Finally, in future RBF process is supposed to be taken into consideration to protect the security of water supply from waterborne pathogens. [ABSTRACT FROM AUTHOR]

Riverbank filtration (RBF) consists of green drinking water production in many regions and is used as a pre-treatment phase. This study investigates the performance of the RBF in the Nile delta, Egypt, for climate change and population growth scenarios of 2030, 2040, and 2050. This study presents a new method for predicting the sharing of riverbanks considering three cases: i) the river stage controlling the water levels in the river, ii) increasing RBF pumping, and iii) changing the groundwater levels. This last scenario is achieved by changing the general head in the MODFLOW model. The results showed that RBF sharing (RBFS) is a proportion of the river leakage inflow, in which the decrease of the river stage due to the influence of climate change reduced the river leakage inflow and RBFS. In addition, increasing RBF pumping, decreasing RBF pumping, and lowering the groundwater levels due to the increase in the future drinking water pumping for the population growth increased the river leakage inflow and RBFS. Finally, combining the three cases decreased RBFS in the coming years of 2030, 2040, and 2050, respectively, due to more groundwater sharing than the river inflow. The results show that the water budget is a good tool to investigate RBFS compared with MT3D results. This technique can reduce the cost of water quality collection and analysis; moreover, it will help with the estimation of RBF and save time compared with solute transport modeling.

Riverbank filtration (RBF) is an affordable technique to provide drinking water with adequate quality. The ultimate objective of this study is to facilitate the transferability and application of this sustainable technique in Egypt. In this work, a numerical model was constructed using Groundwater Modeling System (GMS) to study the effect of four design parameters on the RBF performance parameters (i.e., river filtrate portion and travel time) with the aid of MODPATH and ZONEBUDGET. The design parameters were: (1) the pumping rates of the RBF wells, (2) number of operating wells, (3) distance between wells and the river, and (4) the spacing between wells. This study was focused on the hydraulic aspects of the technique. The results demonstrated that: (1) the river filtrate portion exceeds 75% regardless of the design conditions, and (2) the hydraulic performance of the RBF technique is highly controlled by the production capacity of the wells and their positions relative to the surface water systems; the spacing between wells has a minimum effect. Two equations were developed to estimate the river filtrate portion and minimum travel time as functions of pumping rate and distance between the pumping well and the river. HIGHLIGHTS Hydraulic aspects of riverbank filtration.; Impact of design parameters on river filtrate portion and travel time.; The relation between over-pumping and river filtrate portion.; Multi-regression analysis for RBF performance.;

Riverbank Filtration (RBF) Technology has been found to be a safe, renewable, sustainable, and cost-effective drinking water treatment or pretreatment technology. The Egyptian government has recently turned to riverbank filtration to conserve drinking and industrial water at a lower cost and higher efficiency. The study aims to assess the hydraulic performance of the riverbank filtration system in west Sohag, Egypt. MODFLOW and MODPATH 10.2.3 were used under the platform of Groundwater Modeling System (GMS) to construct a hydraulic groundwater flow model to simulate the flow of the riverbank filtration system. Six pumping rates with two scenarios were conducted to investigate the system's hydraulic performance. Water samples were collected from the Nile River, abstraction wells, and groundwater to characterize the water quality. The results indicated that the application of riverbank filtration is promising due to the significant hydraulic connection between the Nile and the aquifer. However, the system hydraulic aspects should be taken into consideration during the design phase as they may affect the RBF hydraulic performance and its efficiency. It became apparent how effective RBF is at eliminating pathogens and suspended solids. Infiltrated water, on the other hand, has higher iron and manganese amounts than the Nile water. HIGHLIGHTS New scope in water treatment process in Egypt.; More sustainable and cost effective for water supply.; Green technology.;

The main challenge of water resource management in high-stress regions, especially in developing countries, is in adopting non-traditional methods to obtain safe drinking water in desired quantities. In Egypt, the riverbank filtration (RBF) system is one of the most common solutions to solve rivers’ water quality issues. Several sites have been investigated, and the system has demonstrated tremendous potential. The drinking water plant in Embaba, Giza, Egypt, is considered in this study to improve the quality of the abstracted water through the vertical well system. The numerical code of MODFLOW and MT3D is used to simulate the impact of using the emplacement of the gravel-pack filter (GPF). Three different scenarios were investigated: the first consists of vertical GPF; the second is horizontal GPF for different geometries, depths, widths or thicknesses, lengths, and permeability of the filter material; and, the third is drilling a pipe filter through the riverbed for different pipe numbers, depths, and the material’s hydraulic conductivity. The results revealed that the riverbank filtration sharing (RBFS) rate was increased by increasing the filter width or thickness at the riverside, the filter pipe numbers, the length of the horizontal filter, and the permeability of filter material. At the same time, the thickness of the river bed decreased by increasing the filter width at the groundwater side. Also, the RBFS was increased by increasing the filter width or the thickness in the two directions and the pipe length. However, it returned to decrease again due to groundwater sharing. Thus, the RBF design should carefully consider the gravel-pack, pipe filter geometry, and permeability impact rate of RBFS.

Due to extensive water exchanges and abundant active biochemical compositions, active and complex hydrogeochemical processes often exist in riverbank filtration (RBF). The distribution of microbes is considered to be profoundly affected by these processes and is considered to impact the hydrogeochemical processes and the migration and transformation of water pollutants in turn and then impact the water quality. The distribution of microbes and their response to the physiochemical properties along a vertical RBF profile perpendicular to the Songhua River in Northeast China was explored by using 16 S rRNA and redundancy analysis (RDA). The results showed that various microbes were found in the vertical riparian filter (RBF) curve, including Actinobacteria, Proteobacteria, Acidobacteria, Chloroflexi, and Firmicutes. With increasing depth (vertical) and distance from the river (lateral), the microbial community and diversity in the RBF sediment profile decreased. Nitrospirota, Pseudomonas, Gammaproteobacteria, Ochrobactrum, Acinetobacter and Desulfobacterota of the RBF core taxa were also significantly correlated with the biotransformation behavior of typical groundwater pollutants (ammonia, Fe, Mn and S). The amount of As in the RBF is too low to sustain microbial survival. Some microbes in RBF can also degrade natural organic pollutants. This study not only revealed the spatial distribution of geological microbes under the impact of hydrological processes but also lays a foundation for the further study of the hydrobiogeochemical processes of active biochemical compositions in groundwater and water quality evolution, which is of positive significance to ensure the quality safety of the drinking water supplied by RBFs.

Although riverbank filtration (RBF) has been widely applied in China, the managers do not pay enough attention to the inevitable clogging issues during continuous RBF operation. The RBF site, which is located near the Lalin River, northeastern China, was selected as the study area, and the laboratory column experiments were used to simulate the RBF process and further investigate the physical and chemical clogging. The removal of turbidity (59.4–95.1%), COD (21.9–71.7%), NH4+ (10.9–39.4%), Fe (18.5–64.8%), and Mn (19.8–71.7%) demonstrated the water quality improvement by RBF. Whereas, the significant decrease in permeability (39.6–88.2%) also indicated that the clogging issues could not be ignored during RBF. Among them, the physical clogging-dominated area, chemical clogging-dominated area, and the transition zone were located at 0–12.5%, 37.5–100%, and 12.5–37.5% of the infiltration pathway, respectively. Moreover, the concentration of suspended particle materials, mean size of riverbed sediments, and aquifer media are the major impact factors for physical clogging; the precipitation of soluble constituents and redox reaction and other hydrochemical processes were the major impact factors for chemical clogging. The conclusion of this study can contribute to managers alleviating the clogging issues and improving the effectiveness of the sustainable operation in the local RBF system. [ABSTRACT FROM AUTHOR]

In drinking water supply, riverbank filtration (RBF) is an efficient and cost-effective way of eliminating pathogens and micropollutants using a combination of biotic and abiotic processes. Microbial communities in the hyporheic zone both contribute to and are shaped by these processes. Microbial water quality at the point of consumption is in turn influenced by the source water microbiome, water treatment and distribution system. Understanding microbial community shifts from source to tap and the factors behind them is instrumental in maintaining safe drinking water delivery. To this end, microbial communities of an RBF-based drinking water supply system were investigated by metabarcoding in a one-year sampling campaign. Samples were collected from the river, RBF wells, treated water, and a consumer’s tap. Metabarcoding data were analysed in the context of physicochemical and hydrological parameters. Microbial diversity as well as cell count decreased consistently from the surface water to the tap. While Proteobacteria were dominant throughout the water supply system, typical river water microbiome phyla Bacteroidota, Actinobacteria, and Verrucomicrobiota were replaced by Nitrospira, Patescibacteria, Chloroflexi, Acidobacteriota, Methylomicrobilota, and the archaeal phylum Nanoarcheota in well water. Well water communities were differentiated by water chemistry, in wells with high concentration groundwater derived iron, manganese, and sulphate, taxa related to iron and sulphur biogeochemical cycle were predominant, while methane oxidisers characterised the more oxic wells. Chlorine-resistant and filtration-associated taxa (Acidobacteria, Firmicutes, and Bdellovibrionota) emerged after water treatment, and no potentially pathogenic taxa were identified at the point of consumption. River discharge had a distinct impact on well water microbiome indicative of vulnerability to climate change. Low flow conditions were characterised by anaerobic heterotrophic taxa (Woesarchaeales, Aenigmarchaeales, and uncultured bacterial phyla MBNT15 and WOR-1), implying reduced efficiency in the degradation of organic substances. High flow was associated the emergence of typical surface water taxa. Better understanding of microbial diversity in RBF water supply systems contributes to preserving drinking water safety in the future changing environment.

From 2014 to 2020, a full-scale horizontal well was operated to investigate the performance of full-scale riverbank filtration (RBF) in the Nakdong River in Korea, which is significantly impacted by the effluents from sewage treatment plants. In this study, an individual lateral full-scale horizontal collector well was investigated for the first time in Korea, and its performance was determined based on the turbidity and levels of iron, total nitrogen, dissolved organic matter, and four selected trace organic contaminants (TrOCs) (tebuconazole, hexaconazole, iprobenfos, and isoprothiolane) in the RBF and Nakdong River. The turbidity of the river was high with an average of 10.8 NTU, while that of the riverbank filtrate was 0.5 NTU or less on average. The average dissolved organic carbon (DOC) concentrations were 2.5 mg/L in the river water and 1.4 mg/L in the riverbank filtrate, which indicated a 44% reduction in DOC content during the RBF. Out of the 10 laterals, 8 laterals exhibited similar levels of iron, manganese, total nitrogen, DOC, and total hardness, electrical conductivity, and turbidity. The characteristics of the remaining two laterals were different. Because the groundwater inflow was relatively low (<10%), the laterals were contaminated by agricultural land use before the installation of the RBF. This is the first study to report changes in water quality according to individual laterals in a river affected by wastewater effluents. The filtration unit exhibited more than 90% removal rates for tebuconazole and hexaconazole. However, the removal rate for iprobenfos was approximately 77%, while that for isoprothiolane was 46%. The four selected TrOCs in this study were not detected in the groundwater. We found that some organic micropollutants were effectively removed by the RBF. [ABSTRACT FROM AUTHOR]

In the present work measurements of chloride concentrations were used to assess the variability of infiltration conditions and contributions of surface water and local groundwater to the discharge of wells at Krajkowo riverbank filtration site (western Poland). Tests were performed on samples from 26 wells located in a well gallery close to the River Warta. Due to higher chloride concentrations in river water in comparison with local groundwater, significant differences in concentrations in samples from individual wells were noted. In particular, lower chloride concentrations in 11 wells were recorded, which can be linked to the local occurrence of low-permeability deposits in the superficial zone; a locally higher degree of riverbed sediment clogging in the highly convex meandering zone, where strong erosion of the riverbed occurred, which in turn led to increased clogging; the occurrence of a more intensive groundwater inflow into the river valley due to water infiltration from a smaller river entering the River Warta valley, as well as unfavourable conditions for the infiltration of surface water to the lower part of the aquifer with a greater thickness. Differences in chloride concentrations observed were also used to quantify approximately river water contribution to the well production. The average contribution of the River Warta to the recharge of the entire well gallery was estimated at 59.8%.

Study region: A riparian zone within the Songhua River Basin in Northeast China, characterized by a continental monsoon semi-humid climate. Study focus: River infiltration is an important part of groundwater recharge at riverbank filtration (RBF) sites and largely depends on the riverbed hydraulic conductivity (RHC). The influence of river scouring and deposition on RHC is not completely clear, resulting in calculation inaccuracies in the rate of river water infiltration to the aquifer. Thus, the study determined the relationship between RHC and sediment particle size using stepwise regression analysis and a genetic algorithm. A hydrodynamic and sediment transport model (Delft3D) was used to simulate the spatial distribution of sediment particle sizes. A numerical groundwater flow model was also established, using Visual MODFLOW, in which the river boundary was generalized into a third type of boundary condition, and RHC zoning was performed to improve the accuracy of the simulation. New hydrological insights: The findings showed that accurate prediction of RHC is essential for the assessment of groundwater resources in riparian zones. This is crucial for RBF managers, as they will be able to adjust the pumping rate according to the hydrological conditions of the river to either access more water resources in wet years or avoid a series of ecological and geological problems caused by excessive groundwater exploitation in dry years.

Groundwater exploitation in a riparian zone causes water infiltration from the river into the aquifer. Owing to adsorption and redox reactions along the flow path, the quality of water flowing from the river to groundwater wells is variably altered. The riverbed composition often involves spatiotemporal differences due to frequent changes in hydrological conditions. These changes create uncertainties in the transport and removal of solutes in the river water. In this study, the hydrodynamic field associated with riparian groundwater, changes in the structure of riverbed sediments caused by erosion and deposition, fluctuations in surface water and groundwater levels, and the removal efficiency of pollutants from groundwater through pumping were investigated. This involved in situ monitoring and sample testing of the composition of the river water, riverbed sediments, riverbed pore water, and groundwater during dry and wet seasons. Implementation of field in situ column experiments and molecular biology evidences were conducive to identifying the main biogeochemical processes occurring in the riverbed. The findings indicated that riparian groundwater exploitation alters the natural groundwater flow field, while fine sand deposition and microbial adsorption can reduce river recharge to aquifers by diminishing riverbed hydraulic conductivity. Shallow sediments within 1 m depth mainly involve NO 3 − reduction and E. coli adsorption. Reductive dissolution of Mn dominates in the deeper sediments. Additionally, reductive dissolution of Fe and dissimilatory nitrate reduction to ammonium (DNRA) drive high Fe2+ and NH 4 + concentrations in groundwater. The findings can improve the management of riparian groundwater and aid in the optimization of a plan for its exploitation. [Display omitted] • More than 90% of nitrates and E.coli are removed within 1m of the riverbed. • Reduction dissolution of minerals increases iron and manganese levels in groundwater. • Nitrate reduction drives high concentrations of NH 4 + in riparian groundwater. • Iron, manganese and ammonium are potential risks for riverbank filtration systems. [ABSTRACT FROM AUTHOR]

An experimental field study was performed to investigate riverbed clogging processes and associated monitoring approaches near a dam-controlled riverbank filtration facility in Northern California. Motivated by previous studies at the site that indicated riverbed clogging plays an important role in the performance of the riverbank filtration system, we investigated the spatiotemporal variability and nature of the clogging. In particular, we investigated whether the clogging was due to abiotic or biotic mechanisms. A secondary aspect of the study was the testing of different methods to monitor riverbed clogging and related processes, such as seepage. Monitoring was conducted using both point-based approaches and spatially extensive geophysical approaches, including: grain-size analysis, temperature sensing, electrical resistivity tomography, seepage meters, microbial analysis, and cryocoring, along two transects. The point monitoring measurements suggested a substantial increase in riverbed biomass (2 orders of magnitude) after the dam was raised compared to the small increase (~2%) in fine-grained sediment. These changes were concomitant with decreased seepage. The decreased seepage eventually led to the development of an unsaturated zone beneath the riverbed, which further decreased infiltration capacity. Comparison of our time-lapse grain-size and biomass datasets suggested that biotic processes played a greater role in clogging than did abiotic processes. Cryocoring and autonomous temperature loggers were most useful for locally monitoring clogging agents, while electrical resistivity data were useful for interpreting the spatial extent of a pumping-induced unsaturated zone that developed beneath the riverbed after riverbed clogging was initiated. The improved understanding of spatiotemporally variable riverbed clogging and monitoring approaches is expected to be useful for optimizing the riverbank filtration system operations.

An experimental field study was performed to investigate riverbed clogging processes and associated monitoring approaches near a dam-controlled riverbank filtration facility in Northern California. Motivated by previous studies at the site that indicated riverbed clogging plays an important role in the performance of the riverbank filtration system, we investigated the spatiotemporal variability and nature of the clogging. In particular, we investigated whether the clogging was due to abiotic or biotic mechanisms. A secondary aspect of the study was the testing of different methods to monitor riverbed clogging and related processes, such as seepage. Monitoring was conducted using both point-based approaches and spatially extensive geophysical approaches, including: grain-size analysis, temperature sensing, electrical resistivity tomography, seepage meters, microbial analysis, and cryocoring, along two transects. The point monitoring measurements suggested a substantial increase in riverbed biomass (2 orders of magnitude) after the dam was raised compared to the small increase (~2%) in fine-grained sediment. These changes were concomitant with decreased seepage. The decreased seepage eventually led to the development of an unsaturated zone beneath the riverbed, which further decreased infiltration capacity. Comparison of our time-lapse grain-size and biomass datasets suggested that biotic processes played a greater role in clogging than did abiotic processes. Cryocoring and autonomous temperature loggers were most useful for locally monitoring clogging agents, while electrical resistivity data were useful for interpreting the spatial extent of a pumping-induced unsaturated zone that developed beneath the riverbed after riverbed clogging was initiated. The improved understanding of spatiotemporally variable riverbed clogging and monitoring approaches is expected to be useful for optimizing the riverbank filtration system operations.

Study region: Poland, Warta River catchment. Study focus: The study aimed to explain the reasons for spatial variability in chloride concentrations at the Mosina-Krajkowo riverbank filtration (RBF) site located along the river. This variability is attributed to RBF’s different intensity along the river sections, related, among others, to clogging development. The RBF effectiveness was studied using groundwater flow modelling by: examining the water balance in zones established on hydrogeological setting and chloride concentrations; travel time of the bankfiltrate investigation; RBF parametrisation (i.e. infiltration per unit area and specific infiltration per unit of riverbank). New Hydrological Insights for the Region: The study identifies zones of the most favourable RBF conditions and establishes the variability causes. The overall share bankfiltrate was found at 75.8 %. Its spatial variation ranged widely from 41.1–89.3%, confirming the usefulness of the RBF performance sectional analysis in managing this type of site. The highest proportion of surface water (>80 %) occurred along the straight river section, where the riverbed was built by fine and medium sands (preventing penetration of organic suspension into the aquifer). In contrast, the lowest values (

Study region: This study focuses on the simulation of flow and transport of potential contaminants at the riverbank filtration (RBF) site at Embaba, Cairo. RBF has a high potential along the Nile in Egypt as a pre-treatment step for drinking water production. As the site in Cairo can be affected by low water quality and spills of contaminants, the aim was to assess the RBF efficiency under various hydrological, geohydraulic and operational conditions. Study focus: MODFLOW, MT3D and MODPATH were used in this study. Three cases were considered to identify the share of bank filtrate in pumped water and the travel time. The first case focused on the river hydrograph and the permeability of the riverbed; the second on clay cap thickness, aquifer and riverbed hydraulic conductivities, and groundwater abstraction downside of the RBF scheme; and the third on different RBF well abstraction rates, depths, screen lengths and distances from the river bank. New hydrological insights for the region: The results indicate that favorable conditions for RBF sites. Good conditions for RBF include high river stage and riverbed permeability, high aquifer hydraulic conductivity and abstraction rates resulting in high portions of bank filtrate. Design and operation analysis indicate that the abstraction wells should be shallow and located close to the river bank to achieve shorter travel times, thus increasing productivity and preventing high manganese concentrations in the pumped bank filtrate. Due to the natural flow gradient from the Nile towards the RBF wells, changing conditions have impact on the portions of bank filtrate, making the site special.

From 2014 to 2020, a full-scale horizontal well was operated to investigate the performance of full-scale riverbank filtration (RBF) in the Nakdong River in Korea, which is significantly impacted by the effluents from sewage treatment plants. In this study, an individual lateral full-scale horizontal collector well was investigated for the first time in Korea, and its performance was determined based on the turbidity and levels of iron, total nitrogen, dissolved organic matter, and four selected trace organic contaminants (TrOCs) (tebuconazole, hexaconazole, iprobenfos, and isoprothiolane) in the RBF and Nakdong River. The turbidity of the river was high with an average of 10.8 NTU, while that of the riverbank filtrate was 0.5 NTU or less on average. The average dissolved organic carbon (DOC) concentrations were 2.5 mg/L in the river water and 1.4 mg/L in the riverbank filtrate, which indicated a 44% reduction in DOC content during the RBF. Out of the 10 laterals, 8 laterals exhibited similar levels of iron, manganese, total nitrogen, DOC, and total hardness, electrical conductivity, and turbidity. The characteristics of the remaining two laterals were different. Because the groundwater inflow was relatively low (

In the paper, a comparison of the efficiency of riverbank treatments is outlined for the Krajkowo well field, where different methods of water abstraction are used. The water is extracted from 29 vertical wells that are located at a distance of 60–80 m from the channel of the River Warta and from a horizontal well with radial drains located 5 m below the bottom of the river. The results of a two-year water-quality investigation indicate that the water quality in both types of abstraction system is influenced by the quality of river water. The water quality observed in the horizontal well is closely similar to that of the river water, with similar concentrations of sulphates, nitrates and micropollutants, but a reduction in bacteriological contamination and plankton is clearly seen. The reduction in contaminants is mainly the result of physical processes, such as mechanical entrapment of suspended material and colloids as well as bacteria and plankton. In the vertical wells, the influence of contamination from river water is also visible, but the reduction in contamination is more significant, especially in cases of bacteria, plankton, micropollutants and nitrates, and is determined by both physical and chemical processes, such as sorption, dissolution, red-ox processes and denitrification. The present research shows that river water treatment is more effective in the case of vertical wells. The most favourable distance of a well from the channel of the river, from the perspective of water quality, is 150–200 m, which corresponds to a residence time of about six months.

Abstract In analysing the stream–aquifer interactions and riverbank filtration (RBF) systems, it is very crucial to determine the vertical riverbank and streambed hydraulic conductivity. The riverbank and streambed focused in this investigation are a riverbank of six layers with depths of 38 m and streambed with depths of 9 m connected layers of sediments at 22 test locations and 4 test wells in the Muda River, Malaysia. In the analysis, there were a few tests involved to determine riverbank and hydraulic conductivity of vertical streambed, such as analysis of grain size, pumping test and in situ falling head standpipe permeability tests. The approximate K values of 114 samples and 15 samples taken from riverbanks and streambeds, respectively, were then calculated by employing empirical equation methods [Hazen, Hazen K (cm/s) = d10 (mm), Terzaghi, Beyer, Slichter, Sauerbrei, Kruger, Kozeny–Carman, Zunker, USBR, Zamarin, Barr, Alyamani and Sen, Chapuis, and Krumbein and Monk]. The geometric mean of K for six layers, namely the sandy silt (8.30 m/day), silty sand (47.66 m/day), gravelly sand (150.24 m/day), sandy gravel layer (418.48 m/day), gravelly sand (151.09 m/day) and silty clay (9.36 m/day) as identified characteristics by using grain-size analyses, was greater than the K of pumping test (geometric mean) (31.10 m/day) and the mean obtained from K of permeability tests (7.03 m/day). In general, the K values of upper layer of sediments of streambed were recorded to be larger in comparison with their respective lower layer of sediments. The K value for the upper layer of sediments from all tests located at the left, right and middle parts of the river ranged from 7.56 to 54.77 m/day for upper layer, from 39.80 to 128.40 m/day for middle layer and from 9.11 to 49.92 m/day for lower layer, as described by the grain-size analysis. The value of K ranges based on permeability test indicated that the value of K was from 0.036 to 1.09 m/day for the upper layer and 0.16 to 0.68 m/day for the lower layer of hyporheic sediments zone. Based on the acquired results, the conclusion that the aquifer of the focused area shows possibility for RBF and has the potential to improve the water quality and quantity is referable.

Riverbank filtration (RBF) is a natural technology that is used for river water treatment. This research seeks to investigate the effect of pumping rate on the transport of colloids in RBF. However, this work considered Dissolved Organic Matter (DOM) as a nutrient for bacteria. The mathematical model consists of groundwater flow equation and colloids concentration equations. The equations were solved analytically using parameter expanding method and Eigen function expansion techniques. The results obtained are presented graphically and discussed. It was observed that increase in pumping rate value enhance both the hydraulic head and concentration of colloids which slightly reduces the quality of pumped water from RBF. [ABSTRACT FROM AUTHOR]

Water quality impacts from artisanal and small-scale alluvial (placer) gold mining operations occur in developing economies across several continents including Asia, Africa, and South America. They often occur in remote and/or resource-poor settings in which mitigation strategies must contend with extreme seasonal variation in river flow as well as the economic incentive to periodically churn (mine) alluvial floodplains without riparian restoration. A novel strategy addressing these constraints is herein explored which employs the alluvial floodplain for filtration-driven removal of particulate contaminants and gold from streams. This process of lateral channel filtration is explored in the Rio Nambija of southern Ecuador, in terms of success in achieving the hydraulic objective of passively driven lateral flow, and the corresponding removal of particulate contaminants (e.g., total mercury, lead, iron, and manganese) by filtration. Accumulation of gold was examined to evaluate whether incorporation of this proposed practice in alluvial (placer) mining can reduce particle-bound contaminants in streams and simultaneously increase economic benefit. Excavation of channels lateral to mining-impacted streams was shown to achieve the hydraulic, water quality, and economic (gold accumulation) objectives. The modest flow capture for any given lateral segment, along with the months-long timescale associated with economic gold accumulation and clogging by suspended solids, dictate a “cultivation” process whereby multiple lateral segments are worked annually.

Riverbank filtration leads to purification of water. For India it can be a simple, economical and effective alternative. A few unanswered questions were: Can it work in Indian mountainous regions? Will it be of any advantage in the case of some of the polluted Indian surface waters? With the goal to evaluate use of riverbank filtration as a sustainable technology under widely varying conditions prevalent in India, the effectiveness of riverbank filtration has been examined over the last 10 years. In the case of cleaner surface waters, the wells deliver water free of turbidity and coliform even during monsoon irrespective of well configuration. In the case of polluted source waters, it results in an overall advantage in terms of improved raw water quality, reduced degree and cost of subsequent treatment and decreased levels of disinfection by-products. The study shows riverbank filtration to be an effective and sustainable option for plains as well as the mountainous region.

Riverbank filtration (RBF) is considered as a natural treatment process. During this process, a group of chemical, physical, and biological processes occur when water moves through the soil along the bank of the River Nile, which can act as a conventional treatment process. RBF is one of the most effective solutions that the Egyptian government and responsible parties should embrace. Egypt has started to use the RBF technique widely in many sites through the path of the River Nile. This study provides a detailed analysis of the RBF technique; it represents the outlet quality of the water in a study performed on the River Nile. The effect of RBF on water quality can be measured using the software designed for this study. The study’s main aim is to improve the water quality of the River Nile by removing heavy metals from the water by using an effective and fast method of treatment, which is riverbank filtration. The results of the research’s experimental study show the average percentage of metal removal for iron, cobalt, lead, zinc, and copper are 74.04%, 74.44%, 70.72%, 75.1%, and 70.8%, respectively. These results have proved that RBF acts as a substantial barrier versus heavy metals.

The natural vulnerability of Almendares - Vento basin was assessed by applying the RISK method. This method evaluates four variables: aquifer rock (R), infiltration conditions (I), cover or protective soil (S) and karstification (K). This method is modified through the evaluation of the protective cover or soil by applying the EVERC method. The natural vulnerability map of the basin was obtained at 1:100 000 scale. This research contributes significantly to the development of aquifer protection plans. [ABSTRACT FROM AUTHOR]

Abstract Riverbank filtration (RBF) as a barrier of pathogenic microorganisms and organic micropollutants recently has been proven capable of removing sulfonamides. However, the study about the effect of redox conditions on biodegradation of common and persistent sulfonamides in RBF is limited and the response of microbial communities to sulfonamides stress during RBF is unknown. In this study, two column set-ups (with residence time 5 days and 11 days respectively), simulating different redox conditions of riverbank filtration systems, were operated for seven months to investigate 1) the long-term effect of redox conditions on ng∙L−1 level sulfonamides (sulfapyridine, sulfadiazine, sulfamethoxazole, sulfamethazine, sulfaquinoxaline) removal, and 2) the microbial community evolution represented by the phylogenetic and metabolic function shift under non-lethal selective pressures of sulfonamides. The results showed that sulfonamides were more degradable under anoxic conditions than oxic and suboxic conditions. In the sulfonamides stressed community, the phylogenetic diversity increased slightly. Relative abundance of an intrinsic sulfonamides resistant bacteria Bacillus spp. increased, suggesting that sulfonamide resistance developed in specific bacteria under sulfonamides contamination pressure in RBF systems. At the same time, an activated transport function in the stressed microbial community was noticed. The predicted relative abundance of gene folP , which encodes dihydropteroate synthase, also increased significantly, indicating a detoxification mechanism and sulfonamides resistance potential under non-lethal selective pressures of sulfonamides in RBF systems. Graphical abstract Image 1 Highlights • Longer residence time and anoxic condition will benefit sulfonamides (SNs) attenuation in RBF. • Phylogenetic diversity of bacterial community increased slightly under SNs stress. • SNs resistance developed in specific bacteria under selective pressure. • Activated transport function in bacterial community was developed under SNs stress. [ABSTRACT FROM AUTHOR]

Abstract: The potential of riverbank filtration in the removal of five pesticides commonly used in Colombia (atrazine, ametryn, carbofuran, diuron and propanil) was evaluated through a series of column experiments and solute transport modeling. The experiments consisted of two soil columns run under saturated regime, with sediments and water collected from the rivers Loessnitztal and Elbe (East Germany), respectively. Six experiments were performed at 10 and 20 °C, and the final concentrations of the pesticides were used to solve the one-dimensional advection-dispersion equation using an inverse approach. Variables such as retardation factor, first-order degradation coefficient, and dispersion coefficient were assessed for all the pesticides except propanil, which rapidly degraded in solution. The parameters obtained for one of the experiments were introduced into a groundwater flow model from the Loessnitztal site, and the code MT3DMS was used to simulate a contaminant pulse coming from the river. Four different scenarios were considered to determine the effect of adsorption and degradation on the fate of the pesticides. The results showed that, although the persistence of pesticides depends on the properties of each compound, a maximum of 30% removal was achieved during the column experiments, and a log removal of 9 through the numerical modeling. Because of the sensitivity of the fate of contaminants to sorption and degradation, field and laboratory work should be carried on to determine the removal coefficient of the dissolved and adsorbed phases of the compounds, the type of degradation to be expected, and the real values of longitudinal and transverse dispersivity.Graphical Abstract: [ABSTRACT FROM AUTHOR]

Water suppliers aim to achieve microbiological stability throughout their supply system by regular monitoring of water quality. Monitoring temporal biomass dynamics at high frequency is time consuming due to the labor-intensive nature and limitations of conventional, cultivation-based detection methods. The goal of this study was to assess the value of new rapid monitoring methods for quantifying and characterizing dynamic fluctuations in bacterial biomass. Using flow cytometry and two precise enzymatic detection methods, bacterial biomass-related parameters were monitored at three riverbank filtration sites. Additionally, the treatment capacity of an ultrafiltration pilot plant was researched using online flow-cytometry. The results provide insights into microbiological quality of treated water and emphasize the value of rapid, easy and sensitive alternatives to traditional bacterial monitoring techniques.

Studies on the presence of pharmaceuticals in water were carried out on the riverbank filtration site, Krajkowo−Poznań (Poland). A preliminary investigation conducted in 3 sampling points showed the presence of pharmaceuticals in both surface water and bank filtrate. Based on the above, an extended analysis was made in July, August and October 2018 and included surface water and wells located at a different distance (5−250 m) and travel time (1−150 days) from source water (Warta River). Firstly, 75 compounds (antibiotics, anti-inflammatory and analgesic drugs, psychotropic drugs, x-ray agents and β-blockers) were tested and 25 of them were detected in the river or bank filtrate. The highest concentrations were observed in source water and then were reduced along the flow path. The sampling points located close to the river (

Reclaimed water has been widely used to restore rivers and lakes in water scarce areas as well as in Beijing municipality, China. However, refilling the rivers with reclaimed water may result in groundwater pollution. A three-year field monitoring program was conducted to assess the effect of a riverbank filtration (RBF) system on the removal of nitrogen and organics from the Qingyang River of Beijing, which is replenished with reclaimed water. Water samples from the river, sediment, and groundwater were collected for NO3-N, NH4-N, and chemical oxygen demand (COD) was measured. The results indicate that about 85% of NO3-N was removed from the riverbed sediments. Approximate 92% of NH4-N was removed during the infiltration of water from river to aquifer. On average, 54% of COD was removed by RBF. The attenuation of NO3-N through RBF to the groundwater varied among seasons and was strongly related to water temperature. On the other hand, no obvious temporal variability was identified in the removal of COD. These results suggest that the RBF system is an effective barrier against NO3-N, NH4-N and COD in the Qingyang River, as well as those rivers with similar geological and climatic conditions refilled with reclaimed water. [ABSTRACT FROM AUTHOR]

Riverbank filtration leads to purification of water. For India it can be a simple, economical and effective alternative. A few unanswered questions were: Can it work in Indian mountainous regions? Will it be of any advantage in the case of some of the polluted Indian surface waters? With the goal to evaluate use of riverbank filtration as a sustainable technology under widely varying conditions prevalent in India, the effectiveness of riverbank filtration has been examined over the last 10 years. In the case of cleaner surface waters, the wells deliver water free of turbidity and coliform even during monsoon irrespective of well configuration. In the case of polluted source waters, it results in an overall advantage in terms of improved raw water quality, reduced degree and cost of subsequent treatment and decreased levels of disinfection by-products. The study shows riverbank filtration to be an effective and sustainable option for plains as well as the mountainous region. [ABSTRACT FROM AUTHOR]

The groundwater flow path plays an important role in maintaining hydrological and ecological quality and security, which are important in the comprehensive management and use of both groundwater and surface water. In this study, an integrated multi-tracer-constrained framework was used to determine the groundwater flow path. The results show that there are shallow and deep flow paths in riverbank filtration, controlled by the different permeabilities of riverbed sediments and aquifers at different depths. The contribution of river water to shallow groundwater is less than that to deep groundwater because of the low permeability of the riverbed sediment in the dense muddy layer in the shallow slope of the river valley. This contribution decreases with increasing distance from the Liao River. The shallow groundwater quality is better than the deep groundwater quality because of its longer residence time. [ABSTRACT FROM PUBLISHER]

To meet the increasing water demand and to provide safe drinking water in Egypt, the Holding Company for Water and Wastewater (HCWW) and its affiliated companies have started a program to develop riverbank filtration (RBF) sites in all Egyptian governorates. The paper gives an overview of water quality changes as a result of RBF, during the initial phase of operation at three sites in Upper Egypt, between 2015 and 2018. Significant changes were observed for chloride, sulfate, iron, manganese, ammonium, and in the bacterial counts. After the initiation of pumping from the RBF wells, it took 2 to 8 months until stable water quality was observed for the hydrochemical parameters and 2 to 14 months for the microbiological parameters. The results showed that RBF wells should be operated continuously, to maintain the advantage of lower Fe and Mn concentrations achieved by the wash-out effect in the aquifer zone, between the river bank and the RBF wells.

The paper gives an overview on the changes in water quality during riverbank filtration (RBF) in Budapest. As water from the Danube River is of high quality, no problems occur during regular operation of RBF systems. Additionally, water quality improved through the past three decades due to the implementation of communal wastewater treatment plants and the decline of extensive use of artificial fertilizers in agriculture. Algae counts are used as tracer indicators to identify input of surface water into wells and to make decisions regarding shutdowns during floods. RBF systems have a high buffering capacity and resistance against accidental spills of contaminants in the river, which was proven during the red mud spill in October 2010. The removal rate of microorganisms was between 1.5 log and 3.5 log efficiency and is in the same order as for other RBF sites worldwide.

In order to maintain the sustainable development of pumping wells in riverbank filtration (RBF) and simultaneously minimize the possible negative effects induced, it is vital to design and subsequently optimize the engineering parameters scientifically. An optimizing method named Five-Step Optimizing Method was established by using analytic methods (Mirror-Image Method, Dupuit Equation and the Interference Well Group Method, etc.) systematically in this study considering both the maximum allowable drawdown of the groundwater level and the water demand as the constraint conditions, followed by a case study along the Songhua River of northeast China. It contained three parameters (number of wells, distance between wells, and distance between well and river) for optimizing in the method, in which the well type, depth and radius were beforehand designed and fixed, without the need of optimizing. The interference between wells was found to be a decisive factor that significantly impacts the optimizing effort of all the three parameters. The distance between the well and the river was another decisive factor impacting the recharge from the river and subsequently, the well water yield. There would be more than one optional scheme sometimes in the optimized result, while it’s not yet difficult in practice to single out the optimal one considering both the field setting and the water demand. The established method proved to be applicable in the case study.