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Sylvie Barraud - One of the best experts on this subject based on the ideXlab platform.
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Incidence of hydrological, chemical, and physical constraints on bacterial pathogens, Nocardia cells, and fecal indicator bacteria trapped in an urban stormwater Detention Basin in Chassieu, France
Environmental Science and Pollution Research, 2018Co-Authors: Claire Bernardin-souibgui, Sylvie Barraud, G. Lipeme Kouyi, C. Becouze-lareure, Emilie Bourgeois, Jean-baptiste Aubin, Laure Wiest, Laurence Marjolet, Céline Colinon, Benoit CournoyerAbstract:The nature and fate of urban contaminants washed by stormwater events and accumulating in a Detention Basin (DB) were investigated. Relations between bacterial and chemical contaminants of trapped urban sediments, and field parameters were analyzed. Fecal indicators and some pathogens known to be environmentally transmitted (Nocardia, Pseudomonas aeruginosa, and Aeromonas caviae) were tracked, and their persistence investigated. Six sampling campaigns were carried out over 3 years, using five sites including a settling chamber (SC). Aerosolized bacteria at these sites were also monitored. Deposits in the Basin were made of fine particles and their content in chemical pollutants was found highly variable. High polycyclic aromatic hydrocarbon (PAH) contents were measured but only three pesticides, over 22, were detected. Deposits were significantly contaminated by fecal indicator bacteria (FIB), P. aeruginosa, A. caviae, and by Nocardia. Only A. caviae showed significant numbers in aerosolized particles recovered over the Detention Basin. Nocardia spp. cells heavily contaminated the SC. The efficacy of the Detention Basin at reducing bacterial counts per rain event and over time were estimated. A slight drop in the counts was monitored for fecal indicators but not for the other bacterial groups. Hydrodynamic parameters had a strong impact on the distribution and features of the deposits. Multiple factors impacted the fate of FIB, P. aeruginosa, A. caviae, and Nocardia cells, but in a group dependent manner. Nocardia counts were found positively correlated with volatile organic matter. FIB appeared highly efficient colonizers of the DB.
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event based quantification of emerging pollutant removal for an open stormwater retention Basin loads efficiency and importance of uncertainties
Water Research, 2015Co-Authors: C Sebastian, Celine Becouzelareure, Lipeme G Kouyi, Sylvie BarraudAbstract:Abstract Up to now, emerging contaminants have not been further-studied in in-situ stormwater best management practices and especially in Detention Basins. In this article, the efficiency of a dry stormwater Detention Basin was investigated regarding the removal of 7 alkylphenols and alkylphenol ethoxylates, 9 polybrominated diphenyl ethers, 45 pesticides and bisphenol A. Concentrations of contaminants were obtained by chemical analysis on dissolved and particulate phase distinctly. The removal efficiency was assessed on total, dissolved and particulate phase accounting for the global chain of uncertainty with a 95% confidence interval. Results showed that pesticides (rather hydrophilic) are not trapped in the Detention Basin but are released contrarily to B209 which is mostly in particulate phase. Alkylphenols and alkylphenol ethoxylates are present in both phases and the efficiency is storm event-dependent. Uncertainty consideration in efficiency determination revealed efficiency data, usually presented by raw values are not relevant to conclude on the performance of a Detention Basin. In this case study, efficiency data with a 95% confidence interval indicate that only 35%, 50% and 41% of campaigns showed an impact (in trapping or releasing) of the Detention Basin on alkylphenols and ethoxylates, polybrominated diphenyl ethers and pesticides respectively.
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Event-based quantification of emerging pollutant removal for an open stormwater retention Basin – Loads, efficiency and importance of uncertainties
Water Research, 2015Co-Authors: C Sebastian, G. Lipeme Kouyi, C. Becouze-lareure, Sylvie BarraudAbstract:Up to now, emerging contaminants have not been further-studied in in-situ stormwater best management practices and especially in Detention Basins. In this article, the efficiency of a dry stormwater Detention Basin was investigated regarding the removal of 7 alkylphenols and alkylphenol ethoxylates, 9 polybrominated diphenyl ethers, 45 pesticides and bisphenol A. Concentrations of contaminants were obtained by chemical analysis on dissolved and particulate phase distinctly. The removal efficiency was assessed on total, dissolved and particulate phase accounting for the global chain of uncertainty with a 95% confidence interval. Results showed that pesticides (rather hydrophilic) are not trapped in the Detention Basin but are released contrarily to B209 which is mostly in particulate phase. Alkylphenols and alkylphenol ethoxylates are present in both phases and the efficiency is storm event-dependent. Uncertainty consideration in efficiency determination revealed efficiency data, usually presented by raw values are not relevant to conclude on the performance of a Detention Basin. In this case study, efficiency data with a 95% confidence interval indicate that only 35%, 50% and 41% of campaigns showed an impact (in trapping or releasing) of the Detention Basin on alkylphenols and ethoxylates, polybrominated diphenyl ethers and pesticides respectively.
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Spatial variability of sediment ecotoxicity in a large storm water Detention Basin
Environmental Science and Pollution Research, 2014Co-Authors: Carolina Gonzalez Merchan, Sylvie Barraud, C. Becouze-lareure, Yves Perrodin, Christel Sébastian, Christine Bazin, Gislain Lipeme KouyiAbstract:Detention Basins are valuable facilities for urban storm water management, from both the standpoint of flood control and the trapping of pollutants. Studies performed on storm water have shown that suspended solids often constitute the main vector of pollutants (heavy metals, polycyclic aro- matic hydrocarbon (PAH), etc.). In order to characterise the ecotoxicity of urban sediments from storm water Detention Basins, the sediments accumulated over a 6-year period were sampled at five different points through the surface of a large Detention Basin localised in the east of Lyon, France. A spe- cific ecotoxicological test battery was implemented on the solid phase (raw sediment) and the liquid phase (interstitial water of sediments). The results of the study validated the method formulated for the ecotoxicological characterization of urban sediments. They show that the ecotoxicological effect of the sediments over the Basin is heterogeneous and greater in areas often flooded. They also show the relationship between, on one hand, the physical and chemical characteris- tics of the sediments and, on the other hand, their ecotoxicity. Lastly, they contribute to a better understanding of the dynam- ics of the pollution close to the bottom of Detention Basins, which can be useful for improving their design. The results of this research raise particularly the issue of using oil separators on the surface of Detention Basins.
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accumulated sediments in a large dry stormwater retention Detention Basin physico chemical spatial characterization and evolution estimation of metals pesticides pahs and alkylphenols contents caracterisation spatiale et evolution physico chimique de
2013Co-Authors: C Sebastian, Sylvie Barraud, Celine Becouzelareure, Carolina Gonzalezmerchan, Gislain LipemekouyiAbstract:Physical and chemical characterization of sediments trapped in retention Basins is at stake because transport and treatment for valorization are expensive and depend on their contents. Six-year accumulated sediments in a large dry Detention Basin at the outlet of an industrial catchment were sampled. The characterization is related to physical parameters such as dry and volatile matter, particles size distribution (PSD), density, concentrations of metals, PAHs and in a more original way pesticides and Alkylphenols contents. Globally the sediments are highly polluted in terms of metals, PAHs and in a lesser extent in Alkylphenols, Diuron and Glyphosate/AMPA. A heterogeneous spatial distribution, however low, was noticed for PSD and a rather good spatial homogeneity found for chemical contents except for pesticides whose variability is high. Physical and chemical pollutants contents changed over time in relationship with catchment contributions and the hydrodynamism of the Basin. Inter-sediments layers variability was also highlighted but is unusable in practice.
C Sebastian - One of the best experts on this subject based on the ideXlab platform.
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event based quantification of emerging pollutant removal for an open stormwater retention Basin loads efficiency and importance of uncertainties
Water Research, 2015Co-Authors: C Sebastian, Celine Becouzelareure, Lipeme G Kouyi, Sylvie BarraudAbstract:Abstract Up to now, emerging contaminants have not been further-studied in in-situ stormwater best management practices and especially in Detention Basins. In this article, the efficiency of a dry stormwater Detention Basin was investigated regarding the removal of 7 alkylphenols and alkylphenol ethoxylates, 9 polybrominated diphenyl ethers, 45 pesticides and bisphenol A. Concentrations of contaminants were obtained by chemical analysis on dissolved and particulate phase distinctly. The removal efficiency was assessed on total, dissolved and particulate phase accounting for the global chain of uncertainty with a 95% confidence interval. Results showed that pesticides (rather hydrophilic) are not trapped in the Detention Basin but are released contrarily to B209 which is mostly in particulate phase. Alkylphenols and alkylphenol ethoxylates are present in both phases and the efficiency is storm event-dependent. Uncertainty consideration in efficiency determination revealed efficiency data, usually presented by raw values are not relevant to conclude on the performance of a Detention Basin. In this case study, efficiency data with a 95% confidence interval indicate that only 35%, 50% and 41% of campaigns showed an impact (in trapping or releasing) of the Detention Basin on alkylphenols and ethoxylates, polybrominated diphenyl ethers and pesticides respectively.
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Event-based quantification of emerging pollutant removal for an open stormwater retention Basin – Loads, efficiency and importance of uncertainties
Water Research, 2015Co-Authors: C Sebastian, G. Lipeme Kouyi, C. Becouze-lareure, Sylvie BarraudAbstract:Up to now, emerging contaminants have not been further-studied in in-situ stormwater best management practices and especially in Detention Basins. In this article, the efficiency of a dry stormwater Detention Basin was investigated regarding the removal of 7 alkylphenols and alkylphenol ethoxylates, 9 polybrominated diphenyl ethers, 45 pesticides and bisphenol A. Concentrations of contaminants were obtained by chemical analysis on dissolved and particulate phase distinctly. The removal efficiency was assessed on total, dissolved and particulate phase accounting for the global chain of uncertainty with a 95% confidence interval. Results showed that pesticides (rather hydrophilic) are not trapped in the Detention Basin but are released contrarily to B209 which is mostly in particulate phase. Alkylphenols and alkylphenol ethoxylates are present in both phases and the efficiency is storm event-dependent. Uncertainty consideration in efficiency determination revealed efficiency data, usually presented by raw values are not relevant to conclude on the performance of a Detention Basin. In this case study, efficiency data with a 95% confidence interval indicate that only 35%, 50% and 41% of campaigns showed an impact (in trapping or releasing) of the Detention Basin on alkylphenols and ethoxylates, polybrominated diphenyl ethers and pesticides respectively.
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Accumulated sediments in a Detention Basin: chemical and microbial hazard assessment linked to hydrological processes
Environmental Science and Pollution Research, 2013Co-Authors: C Sebastian, C. Becouze-lareure, S. Barraud, Sébastien Ribun, A. Zoropogui, Didier Blaha, G. Lipeme Kouyi, B. CournoyerAbstract:Accumulated sediments in a 32,000-m3 Detention Basin linked to a separate stormwater system were characterized in order to infer their health hazards. A sampling scheme of 15 points was defined according to the hydrological behaviour of the Basin. Physical parameters (particle size and volatile organic matter content) were in the range of those previously reported for stormwater sediments. Chemical analyses on hydrocarbons, PAHs, PCBs and heavy metals showed high pollutant concentrations. Microbiological analyses of these points highlighted the presence of faecal indicator bacteria (Escherichia coli and intestinal enterococci) and actinomycetes of the genus Nocardia. These are indicative of the presence of human pathogens. E. coli and enterococcal numbers in the sediments were higher at the proximity of the low-flow gutter receiving waters from the catchment. These bacteria appeared to persist over time among urban sediments. Samples highly contaminated by hydrocarbons were also shown to be heavily contaminated by these bacteria. These results demonstrated for the first time the presence of Nocardial actinomycetes in such an urban context with concentrations as high as 11,400 cfu g-1.
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accumulated sediments in a large dry stormwater retention Detention Basin physico chemical spatial characterization and evolution estimation of metals pesticides pahs and alkylphenols contents caracterisation spatiale et evolution physico chimique de
2013Co-Authors: C Sebastian, Sylvie Barraud, Celine Becouzelareure, Carolina Gonzalezmerchan, Gislain LipemekouyiAbstract:Physical and chemical characterization of sediments trapped in retention Basins is at stake because transport and treatment for valorization are expensive and depend on their contents. Six-year accumulated sediments in a large dry Detention Basin at the outlet of an industrial catchment were sampled. The characterization is related to physical parameters such as dry and volatile matter, particles size distribution (PSD), density, concentrations of metals, PAHs and in a more original way pesticides and Alkylphenols contents. Globally the sediments are highly polluted in terms of metals, PAHs and in a lesser extent in Alkylphenols, Diuron and Glyphosate/AMPA. A heterogeneous spatial distribution, however low, was noticed for PSD and a rather good spatial homogeneity found for chemical contents except for pesticides whose variability is high. Physical and chemical pollutants contents changed over time in relationship with catchment contributions and the hydrodynamism of the Basin. Inter-sediments layers variability was also highlighted but is unusable in practice.
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assessment of chemical and microbial hazards in a full scale stormwater Detention Basin their characterization toxicity and fate
2011Co-Authors: C Sebastian, S. Barraud, Christine Bazin, Sébastien Ribun, Didier Blaha, Y Perrodin, B Clozel, B. CournoyerAbstract:Accumulated sediments of a 32,000 m 3 Detention Basin linked to a separate stormwater system were characterized in order to infer their health hazards. A sampling scheme of 15 points was defined. Physical parameters (particles size and volatile organic matter content) were in the range of those previously reported for stormwater sediments. Chemical analyses on hydrocarbons, PAHs, PCBs and heavy metals showed high pollutant concentrations. Bacterial counts of fecal indicators, Escherichia coli and intestinal enterococci, and actinomycetal counts of the hydrophobic Nocardia genus, bacterial groups which all include pathogenic species, were performed on these points. These data indicated a bacterial contamination of the sediments by E. coli and enterococci, with concentrations increasing with their proximity to the low flow gutter receiving continuously water from the catchment and suggested their persistence in urban sediments. Samples highly contaminated by PAHs showed high concentrations of these bacteria. These results demonstrated for the first time the presence of Nocardial actinomycetes in such an urban context with concentrations as high as 11,400 cfu.g �1 . A preliminary analysis of the ecotoxicity of these sediments was performed and revealed a growth inhibition.
Xiaoxiao Zhu - One of the best experts on this subject based on the ideXlab platform.
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combination of lagrangian discrete phase model and sediment physico chemical characteristics for the prediction of the distribution of trace metal contamination in a stormwater Detention Basin
Science of The Total Environment, 2020Co-Authors: Xiaoxiao Zhu, Jean-baptiste Aubin, Vincent Chatain, Mathieu Gautier, Denise Blancbiscarat, Cecile Delolme, Nathalie Dumont, Gislain Lipeme KouyiAbstract:Elevated trace metal concentrations in sediments pose a major problem for the management of stormwater Detention Basins. These Basins provide a nature-based solution to remove particulate pollutants through settling, but the resuspension of these contaminated deposits may impact the quality of both surface and groundwater. A better understanding of trace metal distribution will help to improve Basin design and sediment management. This study aims to predict the distribution of trace metal contamination in a stormwater Detention Basin through (i) investigation of the correlation between metal content in sediments and their settling velocity, and (ii) the coupling of such correlation with a Lagrangian Discrete Phase Model (LDPM). The correlation between Fe, Cr, Cu, Ni, Pb contents and the settling velocity is firstly investigated, based on the sediments collected from 6 sites (inlet and 5 traps at the bottom of a Detention Basin situated in Chassieu, France) during 5 campaigns in 2017. Results show that Fe is strongly correlated to settling velocity and can be considered as a good indicator of trace metal contents. The derived correlation is then combined with a LDPM for the prediction of trace metal distribution, producing results consistent with in situ measurements. The proposed methodology can be applied for other stormwater Basins (dry or wet). As described in this article, the interactions between hydrodynamics and sediment physico-chemical characteristics is crucial for the design and management of stormwater Detention Basins, allowing managers to target the highest contaminated sediments.
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Influence of hydrodynamics and correlation of metal contents with settling velocities on contamination distribution in a stormwater Detention Basin
2019Co-Authors: Xiaoxiao ZhuAbstract:Stormwater Detention Basins have three main functions: storing rainwater to prevent flooding, promoting settling of particulate pollutants, avoiding resuspension and remobilization of settled pollutants to the downstream. The design and the management of such facilities requires the knowledge of hydrodynamic and sediment characteristics, as well as the ability to predict areas where deposits are highly contaminated.The main objective of this PhD work is to identify the areas where pollutant levels in sediments are high in Detention and settling Basin. The studied site is the stormwater Detention Basin (Django Reinhardt Basin or DRB), which is an extended and dry Basin at the outlet of an industrial watershed. This Basin has been the subject of numerous investigations within the framework of the Field Observatory for Urban Water Management (or observatoire de terrain en hydrologie urbaine - OTHU in French).First of all, the measurements of surface velocities by Large-Scale Particle Image Velocimetry (LSPIV) permits to better understand the hydrodynamic behaviour in the Basin. These measurements were used to evaluate CFD (Computational Fluid Dynamics) models. This is the first time this measurement technique has been applied in the case of stormwater management facilities. The results show that CFD models identify the main recirculation zone that promotes settling. These evaluated models were then used to simulate the transport of particulate pollutants, including sedimentation and resuspension. The exploitation of these simulations results enables to (i) identify the preferential areas where resuspended contaminated sediments may be conveyed to the downstream infiltration Basin and (ii) predict the accumulation zones of some metals. Results also demonstrate that iron contents in sediments are strongly correlated to settling velocities and can be considered as a good indicator of the level of heavy metals contamination of sediments. The results obtained in this thesis contribute to improve the design of stormwater Detention and settling Basins and the management of contaminated sediments.
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An Analysis of LSPIV-Based Surface Velocity Measurement Techniques for Stormwater Detention Basin Management
Water Resources Research, 2019Co-Authors: Xiaoxiao Zhu, Gislain Lipeme KouyiAbstract:Stormwater Detention Basins are significant components for the sustainable management of urban stormwater, aiming to control stormwater quantity (prevent from flooding) and quality (trap particulate pollutants by settling). The design and management of such facilities need knowledge of the hydrodynamic characteristics and the sedimentation zones for cleaning purposes. Large‐scale particle image velocimetry (LSPIV), mostly applied in riverine environments, has been proven as a low‐cost, highly efficient, and convenient image‐based methodology for surface velocity measurement. In this study, LSPIV technology is employed to investigate free surface velocity in a field stormwater Detention Basin. The method is first evaluated by comparing its results with those obtained by acoustic Doppler velocimeter at pilot scale. Then, the technique is applied to better understand the main flow field and to explain spatial sediment distribution within an extended stormwater Detention Basin. Results illustrate two main flow patterns, which are consistent with observations and preliminary simulated results. LSPIV‐based free surface velocity field measurements can be used to evaluate numerical models and as a support to predict sediment deposition zones in stormwater Detention Basins and to help for their retrofit and management.
Gislain Lipeme Kouyi - One of the best experts on this subject based on the ideXlab platform.
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An Analysis of LSPIV-Based Surface Velocity Measurement Techniques for Stormwater Detention Basin Management
Water Resources Research, 2019Co-Authors: Xiaoxiao Zhu, Gislain Lipeme KouyiAbstract:Stormwater Detention Basins are significant components for the sustainable management of urban stormwater, aiming to control stormwater quantity (prevent from flooding) and quality (trap particulate pollutants by settling). The design and management of such facilities need knowledge of the hydrodynamic characteristics and the sedimentation zones for cleaning purposes. Large‐scale particle image velocimetry (LSPIV), mostly applied in riverine environments, has been proven as a low‐cost, highly efficient, and convenient image‐based methodology for surface velocity measurement. In this study, LSPIV technology is employed to investigate free surface velocity in a field stormwater Detention Basin. The method is first evaluated by comparing its results with those obtained by acoustic Doppler velocimeter at pilot scale. Then, the technique is applied to better understand the main flow field and to explain spatial sediment distribution within an extended stormwater Detention Basin. Results illustrate two main flow patterns, which are consistent with observations and preliminary simulated results. LSPIV‐based free surface velocity field measurements can be used to evaluate numerical models and as a support to predict sediment deposition zones in stormwater Detention Basins and to help for their retrofit and management.
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Spatial variability of sediment ecotoxicity in a large storm water Detention Basin
Environmental Science and Pollution Research, 2014Co-Authors: Carolina Gonzalez Merchan, Sylvie Barraud, C. Becouze-lareure, Yves Perrodin, Christel Sébastian, Christine Bazin, Gislain Lipeme KouyiAbstract:Detention Basins are valuable facilities for urban storm water management, from both the standpoint of flood control and the trapping of pollutants. Studies performed on storm water have shown that suspended solids often constitute the main vector of pollutants (heavy metals, polycyclic aro- matic hydrocarbon (PAH), etc.). In order to characterise the ecotoxicity of urban sediments from storm water Detention Basins, the sediments accumulated over a 6-year period were sampled at five different points through the surface of a large Detention Basin localised in the east of Lyon, France. A spe- cific ecotoxicological test battery was implemented on the solid phase (raw sediment) and the liquid phase (interstitial water of sediments). The results of the study validated the method formulated for the ecotoxicological characterization of urban sediments. They show that the ecotoxicological effect of the sediments over the Basin is heterogeneous and greater in areas often flooded. They also show the relationship between, on one hand, the physical and chemical characteris- tics of the sediments and, on the other hand, their ecotoxicity. Lastly, they contribute to a better understanding of the dynam- ics of the pollution close to the bottom of Detention Basins, which can be useful for improving their design. The results of this research raise particularly the issue of using oil separators on the surface of Detention Basins.
C. Becouze-lareure - One of the best experts on this subject based on the ideXlab platform.
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Incidence of hydrological, chemical, and physical constraints on bacterial pathogens, Nocardia cells, and fecal indicator bacteria trapped in an urban stormwater Detention Basin in Chassieu, France
Environmental Science and Pollution Research, 2018Co-Authors: Claire Bernardin-souibgui, Sylvie Barraud, G. Lipeme Kouyi, C. Becouze-lareure, Emilie Bourgeois, Jean-baptiste Aubin, Laure Wiest, Laurence Marjolet, Céline Colinon, Benoit CournoyerAbstract:The nature and fate of urban contaminants washed by stormwater events and accumulating in a Detention Basin (DB) were investigated. Relations between bacterial and chemical contaminants of trapped urban sediments, and field parameters were analyzed. Fecal indicators and some pathogens known to be environmentally transmitted (Nocardia, Pseudomonas aeruginosa, and Aeromonas caviae) were tracked, and their persistence investigated. Six sampling campaigns were carried out over 3 years, using five sites including a settling chamber (SC). Aerosolized bacteria at these sites were also monitored. Deposits in the Basin were made of fine particles and their content in chemical pollutants was found highly variable. High polycyclic aromatic hydrocarbon (PAH) contents were measured but only three pesticides, over 22, were detected. Deposits were significantly contaminated by fecal indicator bacteria (FIB), P. aeruginosa, A. caviae, and by Nocardia. Only A. caviae showed significant numbers in aerosolized particles recovered over the Detention Basin. Nocardia spp. cells heavily contaminated the SC. The efficacy of the Detention Basin at reducing bacterial counts per rain event and over time were estimated. A slight drop in the counts was monitored for fecal indicators but not for the other bacterial groups. Hydrodynamic parameters had a strong impact on the distribution and features of the deposits. Multiple factors impacted the fate of FIB, P. aeruginosa, A. caviae, and Nocardia cells, but in a group dependent manner. Nocardia counts were found positively correlated with volatile organic matter. FIB appeared highly efficient colonizers of the DB.
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Event-based quantification of emerging pollutant removal for an open stormwater retention Basin – Loads, efficiency and importance of uncertainties
Water Research, 2015Co-Authors: C Sebastian, G. Lipeme Kouyi, C. Becouze-lareure, Sylvie BarraudAbstract:Up to now, emerging contaminants have not been further-studied in in-situ stormwater best management practices and especially in Detention Basins. In this article, the efficiency of a dry stormwater Detention Basin was investigated regarding the removal of 7 alkylphenols and alkylphenol ethoxylates, 9 polybrominated diphenyl ethers, 45 pesticides and bisphenol A. Concentrations of contaminants were obtained by chemical analysis on dissolved and particulate phase distinctly. The removal efficiency was assessed on total, dissolved and particulate phase accounting for the global chain of uncertainty with a 95% confidence interval. Results showed that pesticides (rather hydrophilic) are not trapped in the Detention Basin but are released contrarily to B209 which is mostly in particulate phase. Alkylphenols and alkylphenol ethoxylates are present in both phases and the efficiency is storm event-dependent. Uncertainty consideration in efficiency determination revealed efficiency data, usually presented by raw values are not relevant to conclude on the performance of a Detention Basin. In this case study, efficiency data with a 95% confidence interval indicate that only 35%, 50% and 41% of campaigns showed an impact (in trapping or releasing) of the Detention Basin on alkylphenols and ethoxylates, polybrominated diphenyl ethers and pesticides respectively.
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Spatial variability of sediment ecotoxicity in a large storm water Detention Basin
Environmental Science and Pollution Research, 2014Co-Authors: Carolina Gonzalez Merchan, Sylvie Barraud, C. Becouze-lareure, Yves Perrodin, Christel Sébastian, Christine Bazin, Gislain Lipeme KouyiAbstract:Detention Basins are valuable facilities for urban storm water management, from both the standpoint of flood control and the trapping of pollutants. Studies performed on storm water have shown that suspended solids often constitute the main vector of pollutants (heavy metals, polycyclic aro- matic hydrocarbon (PAH), etc.). In order to characterise the ecotoxicity of urban sediments from storm water Detention Basins, the sediments accumulated over a 6-year period were sampled at five different points through the surface of a large Detention Basin localised in the east of Lyon, France. A spe- cific ecotoxicological test battery was implemented on the solid phase (raw sediment) and the liquid phase (interstitial water of sediments). The results of the study validated the method formulated for the ecotoxicological characterization of urban sediments. They show that the ecotoxicological effect of the sediments over the Basin is heterogeneous and greater in areas often flooded. They also show the relationship between, on one hand, the physical and chemical characteris- tics of the sediments and, on the other hand, their ecotoxicity. Lastly, they contribute to a better understanding of the dynam- ics of the pollution close to the bottom of Detention Basins, which can be useful for improving their design. The results of this research raise particularly the issue of using oil separators on the surface of Detention Basins.
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Accumulated sediments in a Detention Basin: chemical and microbial hazard assessment linked to hydrological processes
Environmental Science and Pollution Research, 2013Co-Authors: C Sebastian, C. Becouze-lareure, S. Barraud, Sébastien Ribun, A. Zoropogui, Didier Blaha, G. Lipeme Kouyi, B. CournoyerAbstract:Accumulated sediments in a 32,000-m3 Detention Basin linked to a separate stormwater system were characterized in order to infer their health hazards. A sampling scheme of 15 points was defined according to the hydrological behaviour of the Basin. Physical parameters (particle size and volatile organic matter content) were in the range of those previously reported for stormwater sediments. Chemical analyses on hydrocarbons, PAHs, PCBs and heavy metals showed high pollutant concentrations. Microbiological analyses of these points highlighted the presence of faecal indicator bacteria (Escherichia coli and intestinal enterococci) and actinomycetes of the genus Nocardia. These are indicative of the presence of human pathogens. E. coli and enterococcal numbers in the sediments were higher at the proximity of the low-flow gutter receiving waters from the catchment. These bacteria appeared to persist over time among urban sediments. Samples highly contaminated by hydrocarbons were also shown to be heavily contaminated by these bacteria. These results demonstrated for the first time the presence of Nocardial actinomycetes in such an urban context with concentrations as high as 11,400 cfu g-1.