Water

11 pages, 944 KiB

Open AccessFeature PaperArticle

Riverbank Filtration Impacts on Post Disinfection Water Quality in Small Systems—A Case Study from Auburn and Nebraska City, Nebraska

by Matteo D'Alessio, Bruce Dvorak and Chittaranjan Ray

Water 2018, 10(12), 1865; https://doi.org/10.3390/w10121865 - 15 Dec 2018

Cited by 4 | Viewed by 4097

Abstract

Small water systems can experience a fluctuating quality of water in the distribution system after disinfection. As chlorine is the most common disinfectant for small systems, the occurrence of disinfection byproducts (DBPs) represents a common problem for these systems. Riverbank filtration (RBF) can [...] Read more.

Small water systems can experience a fluctuating quality of water in the distribution system after disinfection. As chlorine is the most common disinfectant for small systems, the occurrence of disinfection byproducts (DBPs) represents a common problem for these systems. Riverbank filtration (RBF) can be a valuable solution for small communities located on riverbanks. The objectives of this study were to evaluate (i) the improvements in water quality at two selected RBF systems, and (ii) the potential lower concentrations of DBPs, in particular, trihalomethanes (THMs), in small systems that use RBF. Two small communities in Nebraska, Auburn and Nebraska City, using RBF were selected. Results from this study highlight the ability of RBF systems to consistently improve the quality of the source water and reduce the occurrence of THMs in the distribution water. However, the relative removal of THMs was directly impacted by the dissolved organic carbon (DOC) removal. Different THM concentrations and different DOC removals were observed at the two RBF sites due to the different travel distances between the river and the extractions wells. Full article

(This article belongs to the Special Issue Efficiency of Bank Filtration and Post-Treatment)

► Show Figures

Figure 1

37 pages, 5894 KiB

Open AccessArticle

Microturbines at Drinking Water Tanks Fed by Gravity Pipelines: A Method and Excel Tool for Maximizing Annual Energy Generation Based on Historical Tank Outflow Data

by Thomas John Voltz and Thomas Grischek

Water 2019, 11(7), 1403; https://doi.org/10.3390/w11071403 - 9 Jul 2019

Cited by 7 | Viewed by 8720

Abstract

Wherever the flow of water in a gravity pipeline is regulated by a pressure control valve, hydraulic energy in the form of water pressure can instead be converted into useful mechanical and electrical energy via a turbine. Two classes of potential turbine sites [...] Read more.

Wherever the flow of water in a gravity pipeline is regulated by a pressure control valve, hydraulic energy in the form of water pressure can instead be converted into useful mechanical and electrical energy via a turbine. Two classes of potential turbine sites exist—those with (class 1, “buffered”) and those without (class 2, “non-buffered”) a storage tank that decouples inflow from outflow, allowing the inflow regime to be modified to better suit turbine operation. A new method and Excel tool (freely downloadable, at no cost) were developed for determining the optimal hydraulic parameters of a turbine at class 1 sites that maximize annual energy generation. The method assumes a single microturbine with a narrow operating range and determines the optimal design flow rate based on the characteristic site curve and a historical time series of outflow data from the tank, simulating tank operation with a numerical model as it creates a new inflow regime. While no direct alternative methods could be found in the scientific literature or on the internet, three hypothetically applicable methods were gleaned from the German guidelines (published by the German Technical and Scientific Association for Gas and Water (DVGW)) and used as a basis of comparison. The tool and alternative methods were tested for nine sites in Germany. Full article

(This article belongs to the Special Issue Efficiency of Bank Filtration and Post-Treatment)

► Show Figures

Figure 1

18 pages, 5355 KiB

Open AccessArticle

Water Quality Changes during the Initial Operating Phase of Riverbank Filtration Sites in Upper Egypt

by Rifaat Abdel Wahaab, Ahmed Salah and Thomas Grischek

Water 2019, 11(6), 1258; https://doi.org/10.3390/w11061258 - 15 Jun 2019

Cited by 30 | Viewed by 8700

Abstract

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 [...] Read more.

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. Full article

(This article belongs to the Special Issue Efficiency of Bank Filtration and Post-Treatment)

► Show Figures

Figure 1

16 pages, 2537 KiB

Open AccessArticle

Design and Optimization of a Fully-Penetrating Riverbank Filtration Well Scheme at a Fully-Penetrating River Based on Analytical Methods

by Ya Jiang, Junjun Zhang, Yaguang Zhu, Qingqing Du, Yanguo Teng and Yuanzheng Zhai

Water 2019, 11(3), 418; https://doi.org/10.3390/w11030418 - 26 Feb 2019

Cited by 8 | Viewed by 3634

Abstract

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 [...] Read more.

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. Full article

(This article belongs to the Special Issue Efficiency of Bank Filtration and Post-Treatment)

► Show Figures

Figure 1

14 pages, 1507 KiB

Open AccessArticle

Water Quality Changes during Riverbank Filtration in Budapest, Hungary

by Zsuzsanna Nagy-Kovács, János Davidesz, Katalin Czihat-Mártonné, Gábor Till, Ernő Fleit and Thomas Grischek

Water 2019, 11(2), 302; https://doi.org/10.3390/w11020302 - 11 Feb 2019

Cited by 32 | Viewed by 5803

Abstract

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 [...] Read more.

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. Full article

(This article belongs to the Special Issue Efficiency of Bank Filtration and Post-Treatment)

► Show Figures

Figure 1

17 pages, 1638 KiB

Open AccessArticle

A Water Quality Appraisal of Some Existing and Potential Riverbank Filtration Sites in India

by Cornelius Sandhu, Thomas Grischek, Hilmar Börnick, Jörg Feller and Saroj Kumar Sharma

Water 2019, 11(2), 215; https://doi.org/10.3390/w11020215 - 28 Jan 2019

Cited by 17 | Viewed by 4889

Abstract

There is a nationwide need among policy and decision makers and drinking water supply engineers in India to obtain an initial assessment of water quality parameters for the selection and subsequent development of new riverbank filtration (RBF) sites. Consequently, a snapshot screening of [...] Read more.

There is a nationwide need among policy and decision makers and drinking water supply engineers in India to obtain an initial assessment of water quality parameters for the selection and subsequent development of new riverbank filtration (RBF) sites. Consequently, a snapshot screening of organic and inorganic water quality parameters, including major ions, inorganic trace elements, dissolved organic carbon (DOC), and 49 mainly polar organic micropollutants (OMPs) was conducted at 21 different locations across India during the monsoon in June–July 2013 and the dry non-monsoon period in May–June 2014. At most existing RBF sites in Uttarakhand, Jammu, Jharkhand, Andhra Pradesh, and Bihar, surface and RBF water quality was generally good with respect to most inorganic parameters and organic parameters when compared to Indian and World Health Organization drinking water standards. Although the surface water quality of the Yamuna River in and downstream of Delhi was poor, removals of DOC and OMPs of 50% and 13%–99%, respectively, were observed by RBF, thereby rendering it a vital pre-treatment step for drinking water production. The data provided a forecast of the water quality for subsequent investigations, expected environmental and human health risks, and the planning of new RBF systems in India. Full article

(This article belongs to the Special Issue Efficiency of Bank Filtration and Post-Treatment)

► Show Figures

Figure 1

12 pages, 1928 KiB

Open AccessArticle

Riverbank Filtration for the Water Supply on the Nakdong River, South Korea

by Sung Kyu Maeng and Kyung-Hyuk Lee

Water 2019, 11(1), 129; https://doi.org/10.3390/w11010129 - 12 Jan 2019

Cited by 8 | Viewed by 6231

Abstract

A field study was carried out to investigate the feasibility of a riverbank filtration site using two vertical wells on the Nakdong River, South Korea. The riverbank filtration site was designed to have eleven horizontal collector wells in order to supply 280,000 m [...] Read more.

A field study was carried out to investigate the feasibility of a riverbank filtration site using two vertical wells on the Nakdong River, South Korea. The riverbank filtration site was designed to have eleven horizontal collector wells in order to supply 280,000 m³/day. This field study provided more insight into the fate of the dissolved organic matter’s characteristics during soil passage. The vertical production wells (PWs) were located in different aquifer materials (PW-Sand and PW-Gravel) in order to determine the depth of the laterals for the horizontal collector wells. The turbidity of the riverbank filtrates from the PW-Sand (0.9 NTU) and PW-Gravel (0.7 NTU) was less than 1 NTU, which was the target turbidity of the riverbank filtrate in this study. The iron concentrations were 18.1 ± 0.8 and 25.9 ± 1.3 mg/L for PW-Sand and PW-Gravel respectively, and were higher than those of the land-side groundwater. The biodegradable organic matter-determined biochemical oxygen demand in the river water was reduced by more than 40% during soil passage, indicating that less microbial growth in the riverbank filtrate could be possible. Moreover, the influence of the pumping rates of the vertical wells on the removal of dissolved organic matter and the turbidity was not significant. Full article

(This article belongs to the Special Issue Efficiency of Bank Filtration and Post-Treatment)

► Show Figures

Figure 1

17 pages, 3652 KiB

Open AccessArticle

Combination of River Bank Filtration and Solar-driven Electro-Chlorination Assuring Safe Drinking Water Supply for River Bound Communities in India

by Philipp Otter, Pradyut Malakar, Cornelius Sandhu, Thomas Grischek, Sudhir Kumar Sharma, Prakash Chandra Kimothi, Gabriele Nüske, Martin Wagner, Alexander Goldmaier and Florian Benz

Water 2019, 11(1), 122; https://doi.org/10.3390/w11010122 - 11 Jan 2019

Cited by 16 | Viewed by 5650

Abstract

The supply of safe drinking water in rural developing areas is still a matter of concern, especially if surface water, shallow wells, and wells with non-watertight headworks are sources for drinking water. Continuously changing raw water conditions, flood and extreme rainfall events, anthropogenic [...] Read more.

The supply of safe drinking water in rural developing areas is still a matter of concern, especially if surface water, shallow wells, and wells with non-watertight headworks are sources for drinking water. Continuously changing raw water conditions, flood and extreme rainfall events, anthropogenic pollution, and lacking electricity supply in developing regions require new and adapted solutions to treat and render water safe for distribution. This paper presents the findings of a pilot test conducted in Uttarakhand, India, where a river bank filtration (RBF) well was combined with a solar-driven and online-monitored electro-chlorination system, treating fecal-contaminated Ganga River water. While the RBF well provided nearly turbidity- and pathogen-free water as well as buffered fluctuations in source water qualities, the electro-chlorination system provided disinfection based on the inline conversion of chloride to hypochlorous acid. The conducted sampling campaigns provided complete disinfection (>6.7 log) and the adequate supply of residual disinfectant (0.27 ± 0.17 mg/L). The system could be further optimized to local conditions and allows the supply of microbial-safe water for river bound communities, even during monsoon periods and under the low natural chloride regimes typical for this region. Full article

(This article belongs to the Special Issue Efficiency of Bank Filtration and Post-Treatment)

► Show Figures

Figure 1

12 pages, 2177 KiB

Open AccessArticle

Coupling Riverbank Filtration with Reverse Osmosis May Favor Short Distances between Wells and Riverbanks at RBF Sites on the River Danube in Hungary

by Endre Salamon and Zoltán Goda

Water 2019, 11(1), 113; https://doi.org/10.3390/w11010113 - 10 Jan 2019

Cited by 4 | Viewed by 4619

Abstract

Bank filtration and other managed aquifer recharge techniques have extensive application in drinking water production throughout the world. Although the quality of surface water improves during these natural processes, residence time in the aquifer and length of the flow paths are critical factors. [...] Read more.

Bank filtration and other managed aquifer recharge techniques have extensive application in drinking water production throughout the world. Although the quality of surface water improves during these natural processes, residence time in the aquifer and length of the flow paths are critical factors. A wide range of data is available on the physical–chemical processes and hydraulic conditions, but there is limited knowledge about the top layer of the porous media. An investigation was conducted on the hydraulic behavior and on the change of microbiological indicator parameters in the filter cake. The purpose of the experiment was to: (1) investigate if the reverse osmosis is sustainable when fed with only slow filtered water, and (2) show that a short travel distance can provide extensive pathogen removal and beneficial conditions for the reverse osmosis. A slow sand filter was operated over a one-year long period while changes in head loss and microbiological parameters were being monitored. Head loss and membrane permeability were monitored between 3 November 2016 and 24 October 2018 and microbiological sampling was performed from 19 July 2017 to 6 November 2018. The filtered water was fed to a reverse osmosis (RO) filter as the water above the sand filter had been spiked with dissolved iron. Results show that even a thin biofilm cake of 1–3 mm thickness can result in a significant (10–100%) reduction in microbiological activity in the infiltrate, while favorable short retention times and oxic conditions are maintained. Avoiding anoxic conditions, subsequent iron and manganese dissolution and precipitation is beneficial for membrane processes. Building on these results, it can be stated that when reverse osmosis is directly fed with slow filtered or bank filtered water, (1) a short distance from the surface water body is required to avoid dissolved iron and manganese from entering the groundwater and (2) proper pathogen rejection can be achieved even over short distances. Full article

(This article belongs to the Special Issue Efficiency of Bank Filtration and Post-Treatment)

► Show Figures

Figure 1

14 pages, 2152 KiB

Open AccessArticle

The AquaNES Project: Coupling Riverbank Filtration and Ultrafiltration in Drinking Water Treatment

by Robert Haas, Ruediger Opitz, Thomas Grischek and Philipp Otter

Water 2019, 11(1), 18; https://doi.org/10.3390/w11010018 - 21 Dec 2018

Cited by 15 | Viewed by 7636

Abstract

Natural water treatment techniques combined with engineered solutions were investigated at demonstration sites in Europe within the AquaNES project. Ultrafiltration is well-established in water treatment, but is not feasible for many water utilities due to its high operational costs compared to conventional treatment. [...] Read more.

Natural water treatment techniques combined with engineered solutions were investigated at demonstration sites in Europe within the AquaNES project. Ultrafiltration is well-established in water treatment, but is not feasible for many water utilities due to its high operational costs compared to conventional treatment. These differences in cost are caused by membrane fouling and the associated cleaning required. This study aims to assess the economic and energetic operation factors based on studies of an out/in ultrafiltration treatment plant for river water and bank filtrate. The fouling potential of both raw water sources was investigated as well as the quality of the resulting water. In addition, the results show the potential utility of a combined approach utilizing bank filtration followed by ultrafiltration in drinking water treatment. In a separate consideration of the treatment process, the water quality does not fulfill the requirements of the German drinking water ordinance. A new method for the removal of dissolved manganese from the bank filtrate is presented by inline electrolysis. While this improves water quality, this also has a significant influence on fouling potential and, thus, on operating costs of ultrafiltration. These aspects lead to a fundamental decision for operators to choose between more costly ultrafiltration with enhanced microbiological safety compared to cost-effective but less stringent drinking water treatment via open filtration. Full article

(This article belongs to the Special Issue Efficiency of Bank Filtration and Post-Treatment)

► Show Figures

Figure 1

17 pages, 1318 KiB

Open AccessArticle

Performance of Riverbank Filtration under Hydrogeologic Conditions along the Upper Krishna River in Southern India

by T.B. Boving, K. Patil, F. D’Souza, S.F. Barker, S.L. McGuinness, J. O’Toole, M. Sinclair, A.B. Forbes and K. Leder

Water 2019, 11(1), 12; https://doi.org/10.3390/w11010012 - 21 Dec 2018

Cited by 12 | Viewed by 5036

Abstract

Riverbank filtration (RBF) systems were installed in four rural villages along a 64 km stretch of the upper Krishna River in southern India; with each one designed to supply approximately 2500 people. Site selection criteria included hydrogeological suitability, land availability and access, proximity [...] Read more.

Riverbank filtration (RBF) systems were installed in four rural villages along a 64 km stretch of the upper Krishna River in southern India; with each one designed to supply approximately 2500 people. Site selection criteria included hydrogeological suitability, land availability and access, proximity to villages and their population sizes, and electric power supply. Water samples were collected from the river and the RBF wells over more than one year (November 2015 to December 2017) and were analyzed for Escherichia coli bacteria, major ions, and a range of other physicochemical and chemical parameters. The shallow groundwater at the study sites was also sampled, but less frequently. The hydrogeology of the four RBF systems was described in terms of bore-log data, mixing of river and groundwater, pumping test data, and vertical water column profiling. E. coli removal percentages of >99.9% were observed immediately before and during the monsoon, when E. coli concentrations in the river were the highest. The results provide evidence that RBF installations are challenging but possible under the climate and hydrogeologic conditions prevailing in this part of southern India. Specifically, when installing RBF wells in the study, area one needs to balance the well depth and set-back distance from the river against the limited extent of alluvial deposits. The viability of RBF systems as a domestic water source is also influenced by other factors that are not limited to southern India, including surface water and groundwater salinity, agricultural practices surrounding RBF wells, and the reliability of the power grid. Full article

(This article belongs to the Special Issue Efficiency of Bank Filtration and Post-Treatment)

► Show Figures

Graphical abstract

16 pages, 2351 KiB

Open AccessArticle

Removal of Natural Organic Matter and Organic Micropollutants during Riverbank Filtration in Krajkowo, Poland

by Krzysztof Dragon, Józef Górski, Roksana Kruć, Dariusz Drożdżyński and Thomas Grischek

Water 2018, 10(10), 1457; https://doi.org/10.3390/w10101457 - 16 Oct 2018

Cited by 32 | Viewed by 3791

Abstract

The aim of this article is to evaluate the removal of natural organic matter and micropollutants at a riverbank filtration site in Krajkowo, Poland, and its dependence on the distance between the wells and the river and related travel times. A high reduction [...] Read more.

The aim of this article is to evaluate the removal of natural organic matter and micropollutants at a riverbank filtration site in Krajkowo, Poland, and its dependence on the distance between the wells and the river and related travel times. A high reduction in dissolved organic carbon (40–42%), chemical oxygen demand (65–70%), and colour (42–47%) was found in the riverbank filtration wells at a distance of 60–80 m from the river. A lower reduction in dissolved organic carbon (26%), chemical oxygen demand (42%), and colour (33%) was observed in a horizontal well. At greater distances of the wells from the river, the removal of pharmaceutical residues and pesticides was in the range of 52–66% and 55–66%, respectively. The highest removal of pharmaceutical residues and pesticides was found in a well located 250 m from the river and no micropollutants were detected in a well located 680 m from the river. The results provide evidence of the high efficacy of riverbank filtration for contaminant removal. Full article

(This article belongs to the Special Issue Efficiency of Bank Filtration and Post-Treatment)

► Show Figures

Figure 1

13 pages, 2098 KiB

Open AccessArticle

Behavior of Organic Micropollutants During River Bank Filtration in Budapest, Hungary

by Zsuzsanna Nagy-Kovács, Balázs László, Ernő Fleit, Katalin Czichat-Mártonné, Gábor Till, Hilmar Börnick, Yasmin Adomat and Thomas Grischek

Water 2018, 10(12), 1861; https://doi.org/10.3390/w10121861 - 14 Dec 2018

Cited by 32 | Viewed by 5402

Abstract

This paper summarizes results from a half-year sampling campaign in Budapest, when Danube River water and bank filtrate were analyzed for 36 emerging micropollutants. Twelve micropollutants were detected regularly in both river water and bank filtrate. Bisphenol A, carbamazepine, and sulfamethoxazole showed low [...] Read more.

This paper summarizes results from a half-year sampling campaign in Budapest, when Danube River water and bank filtrate were analyzed for 36 emerging micropollutants. Twelve micropollutants were detected regularly in both river water and bank filtrate. Bisphenol A, carbamazepine, and sulfamethoxazole showed low removal (<20%) during bank filtration on Szentendre Island and Csepel island, whereas 1H-benzotriazole, tolyltriazole, diclofenac, cefepime, iomeprol, metazachlor, and acesulfame showed medium to high removal rates of up to 78%. The concentration range in bank filtrate was much lower compared to river water, proving the equilibration effect of bank filtration for water quality. Full article

(This article belongs to the Special Issue Efficiency of Bank Filtration and Post-Treatment)

► Show Figures

Figure 1

11 pages, 4723 KiB

Open AccessArticle

Flow Analysis through Collector Well Laterals: A Case Study from Sonoma County Water Agency, California

by Matteo D’Alessio, John Lucio, Ernest Williams, James Warner, Donald Seymour, Jay Jasperse and Chittaranjan Ray

Water 2018, 10(12), 1848; https://doi.org/10.3390/w10121848 - 13 Dec 2018

Cited by 1 | Viewed by 3606

Abstract

The Sonoma County Water Agency (SWCA) uses six radial collector wells along the Russian River west of Santa Rosa, to provide water for several municipalities and water districts in north-western California. Three collector wells (1, 2, and 6) are located in the Wohler [...] Read more.

The Sonoma County Water Agency (SWCA) uses six radial collector wells along the Russian River west of Santa Rosa, to provide water for several municipalities and water districts in north-western California. Three collector wells (1, 2, and 6) are located in the Wohler area, and three collector wells (3, 4, and 5) are located in the Mirabel area. The objective of this paper is to highlight the performance of the three collector wells located in the Mirabel area since their construction. The 2015 investigation showed a lower performance of Collectors 3 and 4 compared to their original performances after construction in 1975, while the performance of Collector 5 was relatively stable since 1982. The potential change in capacity could be due to the increase in encrustation observed during the visual inspection of laterals in all three collector wells. Overall, the three collectors are still within the optimal design parameters (screen entrance velocity < 0.305 m min⁻¹ and axial flow velocity of lateral screens < 1.524 m s⁻¹). Full article

(This article belongs to the Special Issue Efficiency of Bank Filtration and Post-Treatment)

► Show Figures

Figure 1

15 pages, 1172 KiB

Open AccessFeature PaperArticle

Water Quality Monitoring in Northern India for an Evaluation of the Efficiency of Bank Filtration Sites

by Heinrich Glorian, Hilmar Börnick, Cornelius Sandhu and Thomas Grischek

Water 2018, 10(12), 1804; https://doi.org/10.3390/w10121804 - 8 Dec 2018

Cited by 25 | Viewed by 5657

Abstract

The study presents results of five sampling campaigns at riverbank filtration sites at the Yamuna and Ganges Rivers in Uttarakhand, Uttar Pradesh and New Delhi 2015–2018. Samples were analyzed for organic micropollutants and general water quality parameters. In New Delhi and Uttar Pradesh, [...] Read more.

The study presents results of five sampling campaigns at riverbank filtration sites at the Yamuna and Ganges Rivers in Uttarakhand, Uttar Pradesh and New Delhi 2015–2018. Samples were analyzed for organic micropollutants and general water quality parameters. In New Delhi and Uttar Pradesh, 17 micropollutants were detected frequently at relevant concentrations. Out of the detected micropollutants, 1H-benzotriazole, caffeine, cotinine, diclofenac, diuron, gabapentin and paracetamol were frequently detected with concentrations exceeding 1000 ng/L. Sites in Uttarakhand showed only infrequent occurrence of organic micropollutants. The mean concentration of micropollutants in the well water was lower compared to the river water. For all sites, removal rates for all micropollutants were calculated from the obtained data. Thereby, the capacity of riverbank filtration for the removal of organic micropollutants is highlighted, even for extremely polluted rivers such as the Yamuna. Full article

(This article belongs to the Special Issue Efficiency of Bank Filtration and Post-Treatment)

► Show Figures

Figure 1

14 pages, 5512 KiB

Open AccessArticle

Lithologic Control of the Hydrochemistry of a Point-Bar Alluvial Aquifer at the Low Reach of the Nakdong River, South Korea: Implications for the Evaluation of Riverbank Filtration Potential

by Md Moniruzzaman, Jeong-Ho Lee, Kyung Moon Jung, Jang Soon Kwon, Kyoung-Ho Kim and Seong-Taek Yun

Water 2018, 10(12), 1763; https://doi.org/10.3390/w10121763 - 1 Dec 2018

Cited by 6 | Viewed by 4157

Abstract

To assess the groundwater−river water interaction in a point-bar alluvial aquifer as a crucial step in site assessment for riverbank filtration, hydrochemical and hydrogeologic investigations were performed on a riverine island at the low reach of the Nakdong River, South Korea. The site [...] Read more.

To assess the groundwater−river water interaction in a point-bar alluvial aquifer as a crucial step in site assessment for riverbank filtration, hydrochemical and hydrogeologic investigations were performed on a riverine island at the low reach of the Nakdong River, South Korea. The site was evaluated for the application of large-scale bank filtration. Unconsolidated sediments (~40 m thick) of the island comprise fine- to medium-grained sand (upper aquifer), silty sand with clay intercalations, and sandy gravel (lower aquifer) in descending order. The intermediate layer represents an impermeable aquitard and extends below the river bottom. A total of 66 water samples were collected for this study; groundwater (n = 57) was sampled from both preexisting irrigation wells, and three multi-level monitoring wells (each 35 m deep). Groundwater chemistry is highly variable, but it shows a distinct hydrochemical change with depth: shallow groundwater (<25 m deep) from the upper aquifer is characteristically enriched in NO₃⁻ and SO₄²⁻, due to agricultural contamination from the land surface, while deeper groundwater (>25 m deep) from the lower aquifer is generally free of NO₃⁻ and relatively rich in F. The lower aquifer groundwater is also higher in pH, and concentrations of K⁺, Mg²⁺, and HCO₃⁻, indicating that the aquifer is likely fed by regional groundwater flow. Such separation of groundwater into two water bodies is the result of the existence of an impermeable layer at intermediate depth. In addition, the hyporheic flow of river water is locally recognized at the upstream part of the upper aquifer as the zone of low TDS (Total Dissolved Solids) values (<200 mg/L). This study shows that the study site does not seem to be promising for large-scale riverbank filtration because 1) the productive, lower aquifer is not directly connected to the bottom of the river channel, and 2) the upper aquifer is severely influenced by agricultural contamination. This study implies that the subsurface hydrogeologic environment should be carefully investigated for site assessment for riverbank filtration, which can be aided by a detailed survey of groundwater chemistry. Full article

(This article belongs to the Special Issue Efficiency of Bank Filtration and Post-Treatment)

► Show Figures

Figure 1

11 pages, 1499 KiB

Open AccessCase Report

Operational Strategies and Adaptation of RBF Well Construction to Cope with Climate Change Effects at Budapest, Hungary

by Zsuzsanna Nagy-Kovács, Balázs László, Elek Simon and Ernő Fleit

Water 2018, 10(12), 1751; https://doi.org/10.3390/w10121751 - 28 Nov 2018

Cited by 6 | Viewed by 4466

Abstract

The objective of this paper is to give an overview on the Hungarian experience of river bank filtration (RBF) systems. The study addresses the conflict, which arises between the stochastic character of river water quantity and quality, and the required standard of drinking-water [...] Read more.

The objective of this paper is to give an overview on the Hungarian experience of river bank filtration (RBF) systems. The study addresses the conflict, which arises between the stochastic character of river water quantity and quality, and the required standard of drinking-water supply. Trends in water levels, flow, and water quality are discussed, along with technical measures and operational rules that were developed for implementation of RBF systems. This paper also provides an overview of the average lifespan of the wells and operational strategies. The emerging reconstruction and reconditioning needs are highlighted, and existing alternatives are presented. Large-scale infrastructural elements, such as the Danube-based RBF systems, have to be adapted to a changing environment. The increasing frequency of floods and droughts stresses the need to implement climate-adapted RBF systems and related operational strategies. Operational strategies which were developed by the Budapest Waterworks to deal with extreme hydrological scenarios are presented. Full article

(This article belongs to the Special Issue Efficiency of Bank Filtration and Post-Treatment)

► Show Figures

Figure 1

16 pages, 2163 KiB

Open AccessArticle

Trace Organic Removal during River Bank Filtration for Two Types of Sediment

by Victoria Burke, Laura Schneider, Janek Greskowiak, Patricia Zerball-van Baar, Alexander Sperlich, Uwe Dünnbier and Gudrun Massmann

Water 2018, 10(12), 1736; https://doi.org/10.3390/w10121736 - 26 Nov 2018

Cited by 19 | Viewed by 4690

Abstract

The process of bank filtration acts as a barrier against many anthropogenic micropollutants, such as pharmaceuticals and industrial products, leading to a substantial improvement of groundwater quality. The performance of this barrier is, however, affected by seasonal influences and subject to significant temporal [...] Read more.

The process of bank filtration acts as a barrier against many anthropogenic micropollutants, such as pharmaceuticals and industrial products, leading to a substantial improvement of groundwater quality. The performance of this barrier is, however, affected by seasonal influences and subject to significant temporal changes, which have already been described in the literature. Much less is known about spatial differences when considering one field site. In order to investigate this issue, two undisturbed cores from a well-investigated bank filtration field site were sampled and operated in the course of a column study. The ultimate aim was the identification and quantification of heterogeneities with regard to the biodegradation of 14 wastewater derived micropollutants, amongst others acesulfame, gabapentin, metoprolol, oxypurinol, candesartan, and olmesartan. While six of the compounds entirely persisted, eight compounds were prone to degradation. For those compounds that were subject to degradation, degradation rate constants ranged between 0.2 day⁻¹ (gabapentin) and 31 day⁻¹ (valsartan acid). Further, the rate constants consistently diverged between the distinct cores. In case of the gabapentin metabolite gabapentin-lactam, observed removal rate constants differed by a factor of six between the cores. Experimental data were compared to values calculated according to two structure based prediction models. Full article

(This article belongs to the Special Issue Efficiency of Bank Filtration and Post-Treatment)

► Show Figures

Figure 1

18 pages, 1861 KiB

Open AccessArticle

The Fate of Dissolved Organic Matter (DOM) During Bank Filtration under Different Environmental Conditions: Batch and Column Studies

by Ahmed Abdelrady, Saroj Sharma, Ahmed Sefelnasr and Maria Kennedy

Water 2018, 10(12), 1730; https://doi.org/10.3390/w10121730 - 26 Nov 2018

Cited by 12 | Viewed by 5293

Abstract

Dissolved organic matter (DOM) in source water highly influences the removal of different contaminants and the dissolution of aquifer materials during bank filtration (BF). The fate of DOM during BF processes under arid climate conditions was analysed by conducting laboratory—scale batch and column [...] Read more.

Dissolved organic matter (DOM) in source water highly influences the removal of different contaminants and the dissolution of aquifer materials during bank filtration (BF). The fate of DOM during BF processes under arid climate conditions was analysed by conducting laboratory—scale batch and column studies under different environmental conditions with varying temperature (20–30 °C), redox, and feed water organic matter composition. The behaviour of the DOM fractions was monitored using various analytical techniques: fluorescence excitation-emission matrix spectroscopy coupled with parallel factor analysis (PARAFAC-EEM), and size exclusion liquid chromatography with organic carbon detection (LC-OCD). The results revealed that DOM attenuation is highly dependent (p < 0.05) on redox conditions and temperature, with higher removal at lower temperatures and oxic conditions. Biopolymers were the fraction most amenable to removal by biodegradation (>80%) in oxic environments irrespective of temperature and feed water organic composition. This removal was 20–24% lower under sub-oxic conditions. In contrast, the removal of humic compounds exhibited a higher dependency on temperature. PARAFAC-EEM revealed that terrestrial humic components are the most temperature critical fractions during the BF processes as their sorption characteristics are negatively correlated with temperature. In general, it can be concluded that BF is capable of removing labile compounds under oxic conditions at all water temperatures; however, its efficiency is lower for humic compounds at higher temperatures. Full article

(This article belongs to the Special Issue Efficiency of Bank Filtration and Post-Treatment)

► Show Figures

Graphical abstract

19 pages, 16332 KiB

Open AccessArticle

Capillary Nanofiltration under Anoxic Conditions as Post-Treatment after Bank Filtration

by Jeannette Jährig, Leo Vredenbregt, Daniel Wicke, Ulf Miehe and Alexander Sperlich

Water 2018, 10(11), 1599; https://doi.org/10.3390/w10111599 - 7 Nov 2018

Cited by 13 | Viewed by 4441

Abstract

Bank filtration schemes for the production of drinking water are increasingly affected by constituents such as sulphate and organic micropollutants (OMP) in the source water. Within the European project AquaNES, the combination of bank filtration followed by capillary nanofiltration (capNF) is being demonstrated [...] Read more.

Bank filtration schemes for the production of drinking water are increasingly affected by constituents such as sulphate and organic micropollutants (OMP) in the source water. Within the European project AquaNES, the combination of bank filtration followed by capillary nanofiltration (capNF) is being demonstrated as a potential solution for these challenges at pilot scale. As the bank filtration process reliably reduces total organic carbon and dissolved organic carbon (DOC), biopolymers, algae and particles, membrane fouling is reduced resulting in long term operational stability of capNF systems. Iron and manganese fouling could be reduced with the possibility of anoxic operation of capNF. With the newly developed membrane module HF-TNF a good retention of sulphate (67–71%), selected micropollutants (e.g., EDTA: 84–92%) and hardness (41–55%) was achieved together with further removal of DOC (82–87%). Fouling and scaling could be handled with a good cleaning concept with acid and caustic. With the combination of bank filtration and capNF a possibility for treatment of anoxic well water without further pre-treatment was demonstrated and retention of selected current water pollutants was shown. Full article

(This article belongs to the Special Issue Efficiency of Bank Filtration and Post-Treatment)

► Show Figures

Figure 1

19 pages, 3656 KiB

Open AccessArticle

The Impact of River Discharge and Water Temperature on Manganese Release from the Riverbed during Riverbank Filtration: A Case Study from Dresden, Germany

by Sebastian Paufler, Thomas Grischek, Marcos Roberto Benso, Nadine Seidel and Thomas Fischer

Water 2018, 10(10), 1476; https://doi.org/10.3390/w10101476 - 19 Oct 2018

Cited by 12 | Viewed by 4415

Abstract

The climate-related variables, river discharge, and water temperature, are the main factors controlling the quality of the bank filtrate by affecting infiltration rates, travel times, and redox conditions. The impact of temperature and discharge on manganese release from a riverbed were assessed by [...] Read more.

The climate-related variables, river discharge, and water temperature, are the main factors controlling the quality of the bank filtrate by affecting infiltration rates, travel times, and redox conditions. The impact of temperature and discharge on manganese release from a riverbed were assessed by water quality data from a monitoring transect at a riverbank filtration site in Dresden-Tolkewitz. Column experiments with riverbed material were used to assess the Mn release for four temperature and three discharge conditions, represented by varying infiltration rates. The observed Mn release was modeled as kinetic reactions via Monod-type rate formulations in PHREEQC. The temperature had a bigger impact than the infiltration rates on the Mn release. Infiltration rates of <0.3 m³/(m²·d) required temperatures >20 °C to trigger the Mn release. With increasing temperatures, the infiltration rates became less important. The modeled consumption rates of dissolved oxygen are in agreement with results from other bank filtration sites and are potentially suited for the further application of the given conditions. The determined Mn reduction rate constants were appropriate to simulate Mn release from the riverbed sediments but seemed not to be suited for simulations in which Mn reduction is likely to occur within the aquifer. Sequential extractions revealed a decrease of easily reducible Mn up to 25%, which was found to reflect the natural stratification within the riverbed, rather than a depletion of the Mn reservoir. Full article

(This article belongs to the Special Issue Efficiency of Bank Filtration and Post-Treatment)

► Show Figures

Figure 1

Journal Menu

Journal Browser

Efficiency of Bank Filtration and Post-Treatment

Share This Special Issue

Special Issue Editors

Special Issue Information

Keywords

Benefits of Publishing in a Special Issue

Published Papers (21 papers)

Further Information

Guidelines

MDPI Initiatives

Follow MDPI