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International audience; The assessment of micropollutants in urban wet weather discharges is essential to improve the knowledge of the impact of such discharges on receiving waters. This study assessed the quality of combined sewer overflows (CSOs) in Ecully (residential catchment) and stormwater runoff in Chassieu (industrial catchment) during rain events by providing data on occurrence and total event mean concentrations (EMCt) of 34 priority substances (PS) (9metals, 13 pesticides, 6 PAHs, 4 alkylphenols and 2 chlorobenzenes) in dissolved and particulate fractions. Over 34 substances monitored, 3 were quantified in urban wet weather discharges of both catchments. For both catchments, 9 metals and 6 PAHs monitored were always quantified, reflecting their ubiquitous presence. For other organic pollutants, only 5 pesticides were quantified and only 2 alkyphenols were measured solely in dissolved fraction. A significant site-to-site difference was observed for metals, PAHs and alkylphenols. The highest concentrations were measured in stormwater runoff in Chassieu vs. Ecully. On the contrary, the diuron concentrations were highest in CSO discharges in Ecully. Distribution of the PS between particulate and dissolved fractions provides information for urban stormwater practitioners. Most PS in urban wet weather discharges were mainly linked to particles (PAHs, Pb, Ti for example). The comparison between daily flows of wastewater treatment plants during dry weather and CSOs daily flows in Ecully showed that stormwater was the most important source of contamination for fluoranthene, benzo(b)fluoranthene and benzo(k)fluoranthene and 7 metals (As, Cr, Co, Cu, Pb, Ti and Zn) in receiving water bodies, but not for pesticides and alkylphenols.

International audience; This paper reports two urban floods in France: the September 2000 flood at the city of Marseille caused by heavy rainfall, and the November 2008 flood in Oullins induced by the Yzeron River overflow. A two-dimensional (2D) depth-averaged model was used to simulate flood hazard and to investigate the uncertainty associated to the forcing inputs. Using a rainfall simulator, several distributions of rainfall inputs over the whole domain were produced for the event of September 2000 in Marseille. Results showed these latter distributions changed the average peak water depth more than other input parameters. The Yzeron River water elevation was the main source of uncertainty in the case of Oullins, but the flow pattern in the floodplain was also influenced by the method representing the urban areas. For both cases, average uncertainty remains high (up to 20% for peak water depth or velocity) and local uncertainty is almost much higher.; Cet article traite de crues urbaines en France: la crue de septembre 2000 à Marseille et la crue de novembre 2008 à Oullins. Un modèle 2D a permis de simuler l'aléa d'inondation et étudier l'incertitude associée aux variables d'entrée. En utilisant un simulateur de pluie pour Marseille, on a pu montrer que la répartition de la pluie influait plus que les autres paramètres. A Oullins, le niveau d'eau dans la rivière était le principal paramètre mais le parcours de l'eau dans la zone urbaine était aussi important. Dans les deux cas, l'incertitude restait en moyenne de l'ordre de 20% sur les hauteurs d'eau et les vitesses maximales mais pouvait localement être bien plus forte.

International audience; Are bioelectrochemical systems suitable to fight against the global warming provoked by the anthropogenic sources of CH4? None of the existing studies on this topic provide clear answers because the performance criteria of the electrochemical treatment and gas quantification methods used so far are questionable. This article redefines this performance criteria (carbon footprint - CF) and shows the importance of the materials and methods used to assess this criteria. Indeed, inappropriate gas quantification methods (pressure not taken into account, quantification only of CH4 and not of CO2) lead to errors on calculating the CF reduction rate from 22% to 68% in closed system. Moreover, this article demonstrates, based on suitable gas quantification methods and by means of triplicate MECs with the anode potential poised at +300 mV with respect to the Ag/AgCl reference, that it is possible to achieve a significant reduction in the CF of 22% of anaerobic biofilms producing CO2 and CH4.