Promouvoir des approches innovantes de recherche-développement en matière de GIRE au Burkina Faso

peer reviewe

Renforcement structurel de la capacité de gestion des ressources en eau pour l'agriculture dans le bassin du Kou (Burkina Faso): Rapport Technique 2 (2005-2006)

Le bassin du Kou, situé dans le sud-ouest du Burkina Faso, est depuis quelques décennies le théâtre de différentes formes de conflits liés à toute une série de problèmes que l’on rencontre généralement dans des zones irriguées. Dans le bassin du Kou, les aménagements hydroagricoles recensés couvrent une superficie totale de près de 3.200 ha. Il s’agit pour l’essentiel de périmètres privés formant la ceinture maraîchère, horticole et fruitière de Bobo-Dioulasso et d’un grand périmètre de 1.200 ha réalisé par l’Etat à Bama et spécialisé dans la production du riz. Outre l’abondance en eau liée à la présence de sources importantes, d’une nappe phréatique facilement exploitable, d’un cours d’eau pérenne et un hivernage à caractère sub-humide, la plupart des utilisateurs d’eau se retrouvent régulièrement en pénurie d’eau à cause d’une augmentation de la population et d’une intensification de l’agriculture irriguée. Ceci conduit les gestionnaires du bassin à rechercher des outils de contrôle et de suivi

HydroCube: a new entity-relationship hydrogeological data model

Managing, handling, and accessing hydrogeological information depend mainly on the applied hydrogeological data models, which differ between institutions and across countries. Growing interest in hydrogeological information diffusion, combined with a need for information availability, require the convergence of hydrogeological data models to make hydrogeological information accessible to multiple users such as universities, administrations, water suppliers, and research organisations. Furthermore, because hydrogeological studies are complex, they require a large variety of high-quality hydrogeological data with appropriate metadata in clearly designed and coherent structures. A need therefore exist to develop and implement hydrogeological data models that cover, as much as possible, the full hydrogeological domain. To respond to these requirements, a new data model, called HydroCube, has been developed for the Walloon Region in Belgium. The HydroCube model presents an innovative holistic “project-based” approach, which covers a full set of hydrogeological concepts and features, allowing for effective hydrogeological project management. This approach enables to store data about the project localisation, hydrogeological equipment, related observations and measurements. In particular, the model focuses on specialized hydrogeological field experiments, such as pumping and tracer tests. This logical data model uses entity-relationship diagrams and it has been implemented in the MS Access environment as the HydroCube database. It has been additionally enriched with a fully functional user-interface

Modélisation mathématique appliquée à la délimitation des zones de protection: cas du site de captage de Vivegnis (plaine alluviale de la Meuse, Belgique)

peer reviewe

Physically-based groundwater vulnerability assessment for groundwater protection and land-use management

Numerous groundwater vulnerability and risk mapping techniques have been developed taking into consideration a variable number of factors. Most common techniques produce maps of indexes based on a relatively empirical combination of weighted factors reflecting the protective effect of underground formations overlying the groundwater resource. The limitation of such methods is related to their use of a qualitative definition of groundwater vulnerability, as opposed to a definition based on a quantitative description of contaminant migration. A physically-based point of view and definition of the vulnerability is proposed and based on three factors describing a pollution event, which are the contaminant transfer time from the hazard location to the 'target', the contamination duration at the 'target' and the level of contaminant concentration reached at the 'target'. This concept allows a clear distinction between conventional aspects and physically-based results in the building of a final vulnerability indicator. This methodology has the further advantage to consider the possible impact of runoff conditions occurring at the land surface and possibly leading to lateral contamination of groundwater through downstream preferential infiltration features, such as karstic features. Practically, this method needs to describe and simulate the pollutant migration in the unsaturated zone and possibly in the saturated zone in order to assess the breakthrough curve at the 'target'. Preliminary application is illustrated on a case-study located in a Néblon limestone basin in Belgium, one of the main groundwater resources for the city of Liège in the Meuse basin. Perspectives are proposed towards a generalisation of the vulnerability concept for risk assessment within a pressure - state - impact framework.Cartographie de la vulnérabilité des eaux souterraines - Application au bassin du Hoyoux - Néblo

Delineation of groundwater protection zones based on tracer tests and transport modelling in alluvial sediments

Regulations aiming to protect exploitable groundwater resources were edicted in Belgium a few years ago. Therefore, prevention and protection zones are defined by law and must be determined practically around each pumping well or spring, based on local hydrogeological conditions. The determination of hydrodynamic and hydrodispersive parameters, characterizing the local flow and transport properties of the aquifer, requires pumping and tracing tests. The interpretation of these field experiments, considering the heterogeneity of the geological layers, is performed through the use of numerical FEM simulations of the groundwater flow and pollutant transport conditions in a deterministic framework. After calibration of the model on experimental measurements, multiple simulations with contaminant injections at various points of the modeled domain allow the determination of the transfer time of the pollutant in the studied aquifer whilst taking the updated heterogeneity into account. On the basis of the computed transfer times in the saturated zone, the various prevention and protection areas can be assessed based on provisions of the law

Appui à la gestion et à la protection des ressources en eau souterraines exploitées dans la région de Bobo Dioulasso (Burkina Faso) - Rapport d'activité N°6 rélatif aux subventions 2010-2011

L’année 2011 correspond à la troisième année de la deuxième phase d’exécution du projet de coopération bilatérale entre le Burkina Faso et Wallonie-Bruxelles International intitulé « Appui à la gestion et à la protection des ressources en eaux souterraines exploitées dans la région de Bobo-Dioulasso ». L’exécution des activités de cette troisième année s’est étalée du 01 octobre 2010 au 31 octobre 2011. L’ensemble des activités réalisées et les résultats obtenus sont repris dans ce document de synthèse.Projet Eaux Souterraine