La Méditerranée au futur : des impacts du changement climatique aux enjeux de l'adaptation

Sommaire 1. Introduction 2. Ce que la science du climat nous dit... et ce qu'elle ne nous dit pas 3. Panorama des impacts attendus du changement climatique en Méditerranée 4. L'adaptation au changement climatique : éléments de cadrage 5. Éléments de bilan des efforts actuels en matière d'adaptation en Méditerranée 6. Conclusion. http://www.abhatoo.net.ma/content/download/13897/238639/version/1/file/mediterranee_futur_impacts_chang_clim_enjeux_adaptation.pd

Priority pollutants in wastewater and combined sewer overflow.

International audienceImplementation of the European Water Framework Directive and its affiliated directives requires Member States to improve their understanding of priority pollutants (PPs) in urban areas and obviously within wastewater systems. As a direct consequence, this study is intended to furnish data on both PP occurrence and the significance of concentrations in wastewater during dry and wet periods within combined sewers. Various sampling sites within the Paris combined sewer network were selected; for each sample, a total of 66 determinants, including metals, polycyclic aromatic hydrocarbons (PAHs), pesticides, organotins, volatile organic compounds, chlorobenzenes, phthalates and alkylphenols, were analysed. A broad range of PPs was observed in wastewater during dry as well as wet weather periods. Of the 66 elements investigated, 33 and 40 priority substances could be observed in raw sewage and wet weather effluent, respectively. As expected, a majority of metals were present in all samples, reflecting their ubiquitous nature. For both periods, chlorobenzenes and most of the pesticides always remained below the limit of quantification, while the majority of other organic pollutants assessed were identified within the microg l(-1) range. As highlighted by the larger number of substances detected in wet weather samples and the significance of their concentrations, runoff via atmospheric inputs and/or surface leaching was found to induce a wider range of PPs (n=40) and lead to higher concentrations of certain metals, PAHs, pesticides and other individual compounds. The data generated during this survey, which constitutes one of the first studies conducted in Europe to report concentrations for a variety of priority substances in wastewater within combined sewers, may be used in the future to identify PPs of potential significance for dry and wet weather periods and targeted for further investigation

Polluants prioritaires dans les rejets urbains de temps de pluie : cas de la ville de Paris

International audienceAbstrat This study was launched to furnish data on both priority pollutant (PP) occurrence and concentrations in combined sewer overflows (CSOs). Hence, one rain event was studied on 13 sites within the Paris sewer network. For each sample, a total of 66 substances, including metals, polycyclic aromatic hydrocarbons (PAHs), pesticides, organotins, volatile organic compounds, chlorobenzenes, phthalates and alkylphenols were analysed. Of the 66 analyzed compounds, 40 PPs including 12 priority hazardous substances were detected in CSOs. Most metals were present in all samples. Chlorobenzenes and most pesticides were never quantified above the limit of quantification while most of the other organic pollutants but DEHP (median concentration 22 μg.l -1) were found in the μg.l -1 range. For the rain event studied, the pollutant loads discharged by CSOs were evaluated and then compared to the pollutant loads conveyed by the Seine River. Under the hydraulic conditions considered and according to the estimations done, this comparison highlights that CSOs are potentially a significant local source of metals, PAHs and DEHP.Résumé Ce travail porte sur les campagnes de mesure initiées par la Ville de Paris et l'Agence de l'Eau Seine -Normandie sur les rejets urbains de temps de pluie (RUTP) au sein du réseau unitaire parisien. Parmi les 66 substances recherchées dans les RUTP, 40 composés dont 12 dangereux prioritaires ont été observés. La plupart des métaux a été très souvent quantifiée. Pour les chlorobenzènes et la plupart des produits phytosanitaires, les concentrations sont inférieures aux limites de quantification, tandis que la majorité des autres polluants organiques (hydrocarbures aromatiques polycycliques (HAP), organoétains, composés organiques volatils, phtalates et alkylphénols), à l'exception du diéthylhexylphthalate (DEHP), présentent globalement des concentrations de l'ordre du µg.l -1 . La comparaison entre les flux de polluants déversés en Seine au cours de l'événement pluvieux étudié et les flux de polluants véhiculés par le fleuve sur une même période de temps sec souligne un impact important des RUTP pour les métaux, les HAP et le DEHP

Priority pollutants in surface waters and settleable particles within a densely urbanized area: case study of Paris (France).

International audienceImplementation of the European Water Framework Directive 2000/60/EC (WFD) requires Member States to expand their collective knowledge of priority pollutants (PPs) within receiving waters. To achieve this objective, information on the occurrence of PPs in surface waters and, more specifically, within densely urbanized areas needs to be collected. This study has therefore been designed to provide information on both PP occurrence and concentration build-up along a heavily urbanized transect of the Seine River in the Paris region (France). A large range of PPs were observed in settleable particles and, to a lesser extent, in the waters surveyed. In surface waters, a total of 18 PPs, including 15 priority hazardous substances, were indeed detected, yet concentrations rarely exceeded the limit of quantification. In fact, only diuron, DEHP, fluoranthene and para-tert-octylphenol are observed on a frequent basis, with concentrations ranging from <0.01 to 1.0 microg l(-1). As regards the Environmental Quality Standards (EQS), 10 substances or groups of substances were found in surface waters to exhibit concentrations above the annual average value, while only the benzo(a)pyrene concentration exceed the maximum allowable level. As for the Canadian Sediment Quality Guidelines, settleable particles collected in the Seine River appear to be heavily contaminated since most samples contain PP levels above the guideline values (18 PPs) and, in many cases, above the probable effect levels (15 PPs), which underscores that the levels of metals, PAHs and PCBs in settleable particles constitute a potential risk to freshwater organisms

Priority substances in combined sewer overflows: Case study of the Paris sewer network

Artcile publié. Water Science and Technology Volume 63, Issue 5, 2011, Pages 853-858International audienceThis study was undertaken to supply data on both priority pollutant (PP) occurrence and concentrations in combined sewer overflows (CSOs). A single rain event was studied on 13 sites within the Paris sewer network. For each sample, a total of 66 substances, including metals, polycyclic aromatic hydrocarbons (PAHs), pesticides, organotins, volatile organic compounds, chlorobenzenes, phthalates and alkylphenols were analyzed. Of the 66 compounds analyzed in all, 40 PPs including 12 priority hazardous substances were detected in CSOs. As expected, most metals were present in all samples, reflecting their ubiquitous nature. Chlorobenzenes and most pesticides were never quantified above the limit of quantification, while the majority of the other organic pollutants, except DEHP (median concentration: 22 μg.l-1), were found to lie in the μg.l-1 range. For the particular rain event studied, the pollutant loads discharged by CSOs were evaluated and then compared to pollutant loads conveyed by the Seine River. Under the hydraulic conditions considered and according to the estimations performed, this comparison suggests that CSOs are potentially significant local source of metals, PAHs and DEHP. Depending on the substance, the ratio between the CSO and Seine River loads varied from 0.5 to 26, underscoring the important local impact of CSOs at the scale of this storm for most pollutants. © IWA Publishing 2011

The Future of the Mediterranean: From Impacts of Climate Change to Adaptation Issues

This summary report has been produced at the request of the Sustainable Development General Commission (CGDD) of the French Ministry of Ecology, Energy, Sustainable Development and Territorial Development (MEEDDAT). It also received the support of the European Commission (DG Research, Circe project - "Climate change and impact research: the Mediterranean environment", FP 6) and the Région Ile de France (R2DS project). Drafted by IDDRI, in collaboration with CIRED, this document provides up-to-date information on conceivable climate trends and on their potential impact on natural resources and the different major sectors of activity for the Mediterranean. Principles and recommendations are also put forward to guide the design and implementation of adaptation strategies, at different levels and in different fields

SOURCES DE MICROPOLLUANTS DANS LES EAUX URBAINES

9 p. (version du 5 septembre 2006, mise en forme)National audienceLes eaux du réseau d'assainissement unitaire de Paris sont chargées en micropolluants et plus particulièrement en Eléments Trace Métalliques (ETM). Lors d'évènements pluvieux particulièrement intenses, ces ETM contenus dans les Rejets Urbains de Temps de Pluie (RUTP) et véhiculés par différentes Voies d'Introduction dans le Réseau d'Assainissement (VIRA), peuvent ne pas être traités en station d'épuration. Ils se retrouvent alors dans le milieu naturel, où ils exercent leurs effets toxiques sur les organismes vivants. Afin de répondre à la directive cadre européenne (2000/60/EU) qui prévoit un bon état écologique du milieu naturel d'ici 2015, il est nécessaire de réduire leurs rejets, ce qui implique de connaître précisément leurs sources. L'objectif de ce travail a donc été de caractériser les différentes VIRA dans l'optique future de déterminer précisément chacune des sources primaires d'ETM. La caractérisation des différentes VIRA a été réalisée par la recherche de signatures spécifiques ou traceurs métalliques. Les VIRA suivantes ont été échantillonnées : ruissellements de toitures, ruissellements de chaussées, eaux usées de temps sec et dépôts du réseau remis en suspension lors des évènements pluvieux. La recherche de ces traceurs a été rendue possible par l'analyse simultanée de 50 éléments métalliques par spectrométrie d'émission atomique (ICP-AES). Il en résulte que toutes les VIRA peuvent être discriminées qualitativement par un ou plusieurs éléments. Néanmoins, il semble difficile, compte-tenus des premiers résultats de considérer l'aspect quantitatif dû à la variabilité spatio-temporelle insuffisamment prise en compte. Aussi est-il nécessaire de continuer à échantillonner et caractériser ces différentes VIRA avant de pouvoir caractériser et quantifier précisément les sources primaires d'ETM

SIGNIFICANCE OF DISSOLVED AND PARTICULATE METAL AND HYDROCARBON DETERMINATIONS IN URBAN RUNOFF SAMPLES

International audienceThe objectives of this paper are (i) to present reliable methods of quantification of both hydrocarbons and metals in dissolved and particulate urban runoff samples as well as atmospheric deposits, (ii) to emphasise on the validation procedure of these methods by using replicates, available certified samples or standard mixtures. NIST 1648 (urban particulate matter), BCR 144 R and 146 R (trace elements in sewage sludge from domestic and industrial origin, respectively), NIST 1643c (trace elements in water), SPS-WW1 and SPS-SW2 (waste and surface waters, respectively), were used with success for validating metal extraction and analysis procedures. In the absence of certified urban runoff sample for particulate or dissolved aliphatic hydrocarbons, NIST SRM 1941a was used as noncertified particulate sample (marine sediment certified only for aromatic hydrocarbons) and Florida TPH mix (NSI Environmental Solutions) as a mixture of 17 dissolved aliphatic hydrocarbons from C 10 to C 40. Such validation procedures enable a better discrimination between sample heterogeneity and determination precision