Identification of groundwater quality trends in a chalk aquifer threatened by intensive agriculture in Belgium; Orban, Philippe ; Dassargues, Alain et alin Hydrogeology Journal (2007), 15(8), 1615-1627 The European Union (EU) has adopted directives requiring that Member States take measures to reach a "good" chemical status of water resources by the year 2015 (Water Framework Directive: WFD). In order ... [plus ▼] The European Union (EU) has adopted directives requiring that Member States take measures to reach a "good" chemical status of water resources by the year 2015 (Water Framework Directive: WFD). In order to achieve the environmental objectives for groundwater, the identification and reversal of significant upward trends in pollutant concentrations are required. A very detailed dataset available for the Hesbaye chalk aquifer in Belgium is used to evaluate tools and to propose efficient methodologies for identifying and quantifying nitrate trends in groundwater. Results indicate that the parametric linear regression and the non-parametric Mann-Kendall tests are robust; however, the latter test seems more adequate as it does not require verification of the normality of the dataset and it provides calculated nitrate trends very comparable to those obtained using linear regression. From a hydrogeological point of view, results highlight a general upward trend in the whole groundwater basin. The extrapolation of the trend analysis results indicates that measures have to be taken urgently in order to avoid further major degradation of groundwater quality within the next 10-70 years. However, a good groundwater quality status cannot be expected in the Hesbaye aquifer for the 2015 EU WFD deadline. [moins ▲] Visualisation de la référence détaillée: 85 (25 ULg) Groundwater - surface water interaction at the catchment scale - case studies in the Meuse basin; ; Orban, Philippe et alin Davis, G. B.; Johntson, C. D.; Trefry, M. G. (Eds.) Groundwater Quality 2007 Securing Groundwater Quality in Urban and Industrial Environments (2007) Visualisation de la référence détaillée: 13 (3 ULg) Large-scale groundwater modelling in the Walloon part of the Meuse basin: challenges and first stepsBrouyère, Serge ; Orban, Philippe ![]() Communication orale (2006, December 14) This presentation described the first steps in the development of large (groundwater body) scale groundwater flow and transport modelling in the Meuse district Visualisation de la référence détaillée: 4 (0 ULg) Etude exploratoire relative à la datation des eaux souterraines en Région wallonne à l’aide du Tritium. Application aux nappes de Hesbaye, du Pays de Herve, Hoyoux-Néblon et du TournaisisOrban, Philippe ; ; Dassargues, Alain et alReport (2006) Visualisation de la référence détaillée: 8 (1 ULg) Groundwater flow and transport delivered for groundwater quality trend forecasting by TREND T2Orban, Philippe ; Brouyère, Serge ![]() Report (2006) In the framework of Workpackage R3 Meuse, the Hydrogeology Group of the University of Liège (HGULg) develops a groundwater flow and transport model for the Geer sub-catchment (tributary of the Meuse ... [plus ▼] In the framework of Workpackage R3 Meuse, the Hydrogeology Group of the University of Liège (HGULg) develops a groundwater flow and transport model for the Geer sub-catchment (tributary of the Meuse) (Figure 1, Deliverable R3.16 (Orban et al 2006)). In the scope of TREND T2, the model will be used to develop trend forecasting tools. The objective of the deliverable is to describe new concepts for large-scale transport modelling, more particularly a modelling approach, the Hybrid Finite Element Mixing Cell (HFEMC) developed by HGULg and implemented in the 3D simulator SUFT3D. First steps for the application to the Geer basin are also presented. [moins ▲] Visualisation de la référence détaillée: 9 (1 ULg) Description of hydrogeological conditions in the Geer sub-catchment and synthesis of available data for groundwater modellingOrban, Philippe ; ; Goderniaux, Pascal et alReport (2006) In the framework of Workpackage R3 Meuse, the Hydrogeology Group of the University of Liège (HGULg) will develop a groundwater flow and transport model for the Geer sub-catchment (tributary of the Meuse ... [plus ▼] In the framework of Workpackage R3 Meuse, the Hydrogeology Group of the University of Liège (HGULg) will develop a groundwater flow and transport model for the Geer sub-catchment (tributary of the Meuse). This model will be used for collaborations HYDRO H1 and TREND T2. The deliverable describes the hydrogeological conditions prevailing in the sub-catchment and provides a synthesis of available data for groundwater and transport modelling. [moins ▲] Visualisation de la référence détaillée: 14 (0 ULg) Characterisation of fissured aquifers in the semi-arid region of the mid-Atlas plateau (Oulmès, Morocco)Orban, Philippe ; Ruthy, Ingrid ; et alin GIRE3D: International Congress on Integrated Water Resources management and Challenges of the Sustainable Development (2006) The Oulmès plateau (mid-Atlas in Morocco) is known for its groundwater resources in this semi-arid region. In the studied zone (approximately 80 km2), the mineral water of ‘Sidi Ali’ is exploited as well ... [plus ▼] The Oulmès plateau (mid-Atlas in Morocco) is known for its groundwater resources in this semi-arid region. In the studied zone (approximately 80 km2), the mineral water of ‘Sidi Ali’ is exploited as well as the naturally semi-sparkling ‘mineral water of Oulmès’ which are main mineral waters marketed in Morocco. Their sources are located at less than four kilometers from each other. In the same time, the drinking water supply to the local rural populations is far from being sufficient, and even in some places non-existent. In addition the plateau is also the place where many fruit-bearing cultures have been undertaken for a few years. Irrigation and the use of pesticide and herbicide compounds as well as fertilizers could constitute threats for the groundwater quantity and quality and unpleasant consequences are expected for all dependent groundwater end-users. Thus, in this semi-arid zone, an acute problem of sustainable development arises in terms of groundwater quantity and quality. An extended study has involved data collection, measurement campaigns (piezometric levels, sampling & analysis of groundwater), shallow geophysical prospecting, pumping tests, building of a data base, estimation of the recharge spatial distribution and hydrogeological mapping. On the basis of this study, a better understanding is possible about the state and the particular hydrodynamic behaviour of groundwater in the fissured hard-rocks of this plateau. Results are expressed in maps providing explicit and useful information allowing future decisions which can be taken for the welfare of everyone and particularly for the local populations. [moins ▲] Visualisation de la référence détaillée: 88 (15 ULg) Developing tools for managing hydrogeological data in a semi-arid region: the case study of Oulmès (Morocco)Ruthy, Ingrid ; Orban, Philippe ; et alin GIRE3D: International Congress on Integrated Water Resources management and Challenges of the Sustainable Development (2006) Data and information required by hydrogeological studies are various and complex such as geology, topography, climate, hydrological and hydrogeological raw or pre-processed data. All these data need to be ... [plus ▼] Data and information required by hydrogeological studies are various and complex such as geology, topography, climate, hydrological and hydrogeological raw or pre-processed data. All these data need to be managed, and this can be done in a structured database. A (GIS-managed) hydrogeological database has been developed previously by the Hydrogeology Group of the University of Liège (Gogu et al., 2001) in order to capture, store, edit, query, update and display geographically referenced hydrogeological data. The development of this geo-relational database was constrained by a maximum storage of data with a minimum data redundancy, reduction of storage memory capacity and optimum ‘retrievability’ of information for further analysis. In recent years, the use of Geographical Information System (GIS) has grown rapidly in groundwater management and research. GIS is now widely used to create digital geographic databases, to manipulate and prepare data as input for various model parameters, and to display model output. Coupling GIS with this hydrogeological database provides a powerful tool. This GIS-managed hydrogeological database has been also developed for vulnerability-assessment techniques and numerical modelling for groundwater flow and contaminant transport studies. As well as linking between database and GIS, the design of coupling database with process-based numerical models was also performed. This methodology has been applied, in a semi-arid region: the "Oulmès plateau" located in the Mid-Atlas (Morocco). This study has led to a detailed hydrogeological map at the scale of 1/25000. First, data were collected from existing databases, studies and maps as well as through new field measurements. These data came from numerous and various sources and in different formats (paper or digital diagrams, images, spreadsheets…). After validation, it has been encoded in the hydrogeological database. Because data are geo-referenced, it can be easily represented on the map within GIS-software. The hydrogeological map displays several layers of information as topography, hydrogeological units, hydrographic network, wells, piezometers, isoline of piezometric heads. [moins ▲] Visualisation de la référence détaillée: 105 (12 ULg) Large-scale groundwater flow and transport modelling : Methodology and application to the Geer basin, BelgiumOrban, Philippe ; Dassargues, Alain ; Brouyère, Serge ![]() in Stauffer, Fr.; Dassargues, Alain (Eds.) Quantitative Geology from Multiple Sources: S10 Use of multiple sources in conditioning/calibrating groundwater flow and transport models (2006) Efficient and sustainable management of water resources should be considered from an integrated way, at the basin scale. For that purpose, physically-based, spatially distributed modelling tools has ... [plus ▼] Efficient and sustainable management of water resources should be considered from an integrated way, at the basin scale. For that purpose, physically-based, spatially distributed modelling tools has turned to be very useful. If regional groundwater flow model have been developed for years now, large scale contaminant transport models are still almost inexistent. The objective of this extended abstract is to present briefly new concepts for large transport modelling, more particularly a modelling approach, the Hybrid Finite Element Mixing Cell (HFEMC) developed by the Hydrogeology Group of the University of Liège and implemented in the 3D simulator SUFT3D. First steps for the application to the Geer basin are also presented. [moins ▲] Visualisation de la référence détaillée: 30 (13 ULg) Identification of groundwater quality trends in a chalky aquifer threatened by intensive agriculture; Orban, Philippe ; Dassargues, Alain et alin Stauffer, Fr.; Dassargues, Alain (Eds.) Quantitative Geology from Multiple Sources: S10 Use of multiple sources in conditioning/calibrating groundwater flow and transport models (2006) Diffuse groundwater contamination related to agricultural practices is a worldwide environmental problem, particularly the continuous increase in nitrate concentrations. As a response to this threat, the ... [plus ▼] Diffuse groundwater contamination related to agricultural practices is a worldwide environmental problem, particularly the continuous increase in nitrate concentrations. As a response to this threat, the European Union has adopted directives requiring that Member States take measures to reduce agricultural nitrate sources and stating that a “good” status of groundwater is required for all EU members. In order to achieve the environmental objectives for groundwater, the identification and reversal of any significant upward trend in the pollutant concentrations are required. Conclusions are drawn about the evolution of groundwater contamination by nitrates in the following decades with respect to the EU Water directive prescriptions. Measures have to be urgently taken in order to avoid major degradation of groundwater in 10 to 70 years. However, a good groundwater quality status cannot be expected for the 2015 EU Water Framework Directive (WFD). [moins ▲] Visualisation de la référence détaillée: 44 (15 ULg) EIE renouvellement de l’usine de valorisation énergétique de déchets ménagers et assimilés à Herstal (partim eaux souterraines); Orban, Philippe ; Dassargues, Alain ![]() Report (2005) Visualisation de la référence détaillée: 11 (3 ULg) Schéma directeur intégré pour la préservation de la qualité de l’eau et la valorisation écologique des lacs de l’Eau d’Heure dans le cadre du développement touristique et économique du siteEverbecq, Etienne ; Deliège, Jean-François ; Bourouag, Mohamed et alReport (2005) Schéma directeur intégré pour la préservation de la qualité de l’eau et la valorisation écologique des lacs de l’Eau d’Heure dans le cadre du développement touristique et économique du site Les barrages ... [plus ▼] Schéma directeur intégré pour la préservation de la qualité de l’eau et la valorisation écologique des lacs de l’Eau d’Heure dans le cadre du développement touristique et économique du site Les barrages de l'Eau d'Heure (cinq plans d’eau, dont deux principaux liés à la construction des deux grands barrages de la Plate Taille et de l'Eau d'Heure) ont comme but principal de soutenir le débit d’étiage de la Sambre, tout en contribuant à réduire les effets des pollutions urbaines et industrielles résiduelles et à soutenir le débit du canal Charleroi-Bruxelles. Outre ces fonctions, le complexe "Eau d'Heure" représente un attrait touristique indéniable. Des infrastructures touristiques importantes ont été construites, elles constituent un risque pour la qualité de l'eau et de l'environnement. Le niveau de qualité de l'eau est préoccupant pour certains lacs ; aussi, dans l'esprit du « Phasing out » de l'objectif 1, il était urgent d'entreprendre des actions au niveau environnemental pour revaloriser le site des lacs de d'Eau d'Heure, aussi bien au niveau du potentiel touristique que de la qualité environnementale en tant que telle. Le "Schéma directeur intégré pour la préservation de la qualité de l'eau et la valorisation écologique des lacs de l'Eau d'Heure dans le cadre du développement touristique et économique du site" est un projet financé par la Région wallonne et par le fonds européen FEDER. Le programme s’est étalé sur trois ans de 2002 à 2004. Dans une première phase (2 ans), un bilan complet de la qualité des eaux a été dressé : niveau d’eutrophisation, bilan des apports d’eau par le bassin versant (ruissellement, écoulements souterrains ou nappes aquifères), bilan des apports de matières organiques et de nutriments en fonction des activités humaines (notamment agricoles). Le fonctionnement écologique de tout le système a aussi fait l’objet d’études détaillées. Le lien entre tous ces éléments, assuré par une modélisation mathématique, a permis de dégager des actions susceptibles de contrôler l’eutrophisation afin de restaurer les milieux naturels et les biocénoses. Durant la deuxième phase, des recommandations de gestion ont été formulées. Le projet était construit sur un partenariat entre IGRETEC et deux institutions universitaires (FUNDP-URBO/GIREA et ULg-Centre Environnement), en relation avec les communes, les administrations wallonnes (MET, DGRNE, DGATLP, Commissariat au Tourisme …) ainsi qu’avec les gestionnaires (MET, AGLEH). Une "Plaquette" est annexée à cette référence, cf. section 'Adjuvant". Elle a été réalisée par le GIREA (Verniers, G. et Leroy, P.) et le URBO (Sarmento, H.) de la FUNDP, et décrit en synthèse les tâches réalisées au cours de cette étude par l'ensemble des partenaires scientifiques. [moins ▲] Visualisation de la référence détaillée: 15 (2 ULg) Carte hydrogéologique du plateau d’Oulmès (Maroc); ; et al Report (2005) Visualisation de la référence détaillée: 105 (3 ULg) Large-scale groundwater flow and transport modeling: Methodology and application to the Meuse Basin – BelgiumOrban, Philippe ; Brouyère, Serge ; et alin Bringing Groundwater Quality Research to the Watershed Scale - Proceedings of GQ2004 (2005) To meet the requirements of the EU Water Framework Directive, an integrated water management project named PIRENE was initiated by the Walloon Region of Belgium. A partner of this project, the ... [plus ▼] To meet the requirements of the EU Water Framework Directive, an integrated water management project named PIRENE was initiated by the Walloon Region of Belgium. A partner of this project, the Hydrogeology Group of the University of Liège, is in charge of the development of a physically based transient groundwater flow and transport model for the Walloon part of the Meuse Basin (approximately 17 000 km2). To face the problems associated with this large-scale model, a general approach has been developed that combines a hydrogeological database and GIS systems to manage data. Techniques of spatial discretization have been applied that optimize the number of unknowns. For modelling groundwater flow and transport on a large scale, a new numerical approach called the Hybrid Finite Element Mixing Cell (HFEMC) has been implemented in the 3-D simulator SUFT3D. [moins ▲] Visualisation de la référence détaillée: 49 (12 ULg) Marché de services en vue de simuler l’impact, sur le régime hydrologique de l’Ourthe, de l’implantation de bassins écrêteurs dans les vallées de l’Ourthe et de l’Amblève (MOHICAN)Deliège, Jean-François ; Bourouag, Mohamed ; et alReport (2004) Le modèle MOHICAN (« Modèle hydrologique intégré pour le calcul des crues et l’amplitude des niveaux d’eau ») a été développé conjointement par l’Université de Liège (Laboratoire d’hydrodynamique ... [plus ▼] Le modèle MOHICAN (« Modèle hydrologique intégré pour le calcul des crues et l’amplitude des niveaux d’eau ») a été développé conjointement par l’Université de Liège (Laboratoire d’hydrodynamique appliquée, Laboratoire de Géologie de l’Ingénieur et d’Hydrogéologie, Centre d’Etude et de Modélisation de l’environnement) et la Faculté Universitaire des Sciences Agronomiques de Gembloux (Unité d’Hydraulique agricole) pour le compte et avec le support du Ministère de l’Equipement et des Transports, Service d’Etudes Hydrologiques (MET/SETHY) de la Région wallonne. En 2004, le SETHY a demandé aux développeurs du projet de simuler l’impact sur le régime hydrologique de l’Ourthe, de bassins écrêteurs dans les vallées de l’Ourthe et de l’Amblève. Plus spécifiquement, les objectifs de l’étude étaient d’estimer l’efficacité réelle de ces bassins écrêteurs (Les Combes, 16.3 Mm³, Ourthe ; Gran Han, 15.0 Mm³, Ourthe ; Stoumont, 5.7 Mm³, Amblève) pour la diminution des débits de pointe et des hauteurs d’eau, en particulier lors de très grandes crues. Dans le cas des grandes crues testée, les simulations montrent clairement la grande sensibilité des résultats aux différentes combinaisons possibles des bassins écrêteurs et surtout aux lois de gestion à utiliser pour ces bassins : il n’existe pas une loi générale qui donne un résultat maximal pour tous les types de grandes crues, et la gestion combinée des bassins est délicate. [moins ▲] Visualisation de la référence détaillée: 10 (2 ULg) Synthesis of data availability for the river Meuse and the aquifer located in the alluvial plain in the Walloon Meuse catchment region; ; Orban, Philippe et alReport (2004) During the three first months of the AQUATERRA project, the Group of Hydrogeology and Environmental Geology from the University of Liège (HGULg) has performed a general inventory of data sources and ... [plus ▼] During the three first months of the AQUATERRA project, the Group of Hydrogeology and Environmental Geology from the University of Liège (HGULg) has performed a general inventory of data sources and availability for the Walloon part of the Meuse basin in Belgium. This deliverable provides the information in the form of a summary table that gives a general description of data types, accessibility (public or confidential, free or charged…) and, if existing, a website with further useful information. In this synthesis, emphasis is put on hydrogeological information. However, general information on surface water is also provided when available. In the following months, needed data will be collected for the Meuse/Basin experimental sites in the Walloon region. Collected datasets will be introduced into the Hydrogeological Database HYGES developed by HGULg. This database is presently updated for the needs of the AQUATERRA Project. This synthesis will be further updated when new information and data sources are available. [moins ▲] Visualisation de la référence détaillée: 7 (2 ULg) Database and general modelling concepts for groundwater modelling in the SQUASH ProjectOrban, Philippe ; ; Ruthy, Ingrid et alin Hidrotehnica (2004), 49(9-10), 51-57 Visualisation de la référence détaillée: 18 (3 ULg) Etude hydrogéologique préliminaire des captages de Modave de la Compagnie Intercommunale Bruxelloise des eauxOrban, Philippe ; Brouyère, Serge ; Dassargues, Alain ![]() Report (2003) Visualisation de la référence détaillée: 15 (1 ULg) MANPORIVERS (Management policies for priority water pollutants and their effects on foods and human health: general methodology and application to Chinese river basins), Hydrogeology part, activity report year 2Dassargues, Alain ; ; Orban, Philippe et alReport (2003) Visualisation de la référence détaillée: 1 (0 ULg) Development of a database linked to a GIS for coupling with groundwater modelling toolsRuthy, Ingrid ; Orban, Philippe ; et alin Iu (Ed.) Computational Methods in Engineering and Science (2003) Groundwater analysis strongly depends on the availability of large volumes of high-quality data. Putting all data in a coherent and logical structure supported by a computing environment helps ensure ... [plus ▼] Groundwater analysis strongly depends on the availability of large volumes of high-quality data. Putting all data in a coherent and logical structure supported by a computing environment helps ensure validity and availability and provides a powerful tool for hydrogeological studies. A hydrogeological Geographical Information System (GIS) database that offers facilities for hydrogeological modeling has been designed in Belgium for the Walloon Region. Interest is growing in the potential for integrating GIS technology and groundwater simulation models. A “loose-coupling” tool was created between the spatial database scheme and the groundwater numerical model interface GMS© (Groundwater Modeling System). Following time and spatial queries, the hydrogeological data stored in the database can be easily used within different groundwater numerical models. [moins ▲] Visualisation de la référence détaillée: 45 (12 ULg) |
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