Etude des chlorations des circuits de refroidissement de la centrale de Tihange et leur impact sur l'écosystème Meuse

Etude subsidiée pour le compte du Ministère de la Région Wallonne, pour l'Eau, l'Environnement et la Vie Rurale. Rapport finalinfo:eu-repo/semantics/publishe

Phytoplankton biomass and production in the River Meuse (Belgium)

The biomass and production of the phytoplankton in a relatively unpolluted reach of the River Meuse were followed through 1983 and 1984. Chlorophyll a varied from 0.2 to about 120 mg/cu m, and production ranged between 0.05 and 5.78 g C/sq m/day. The mean photosynthetic quotient was 1.25. The parameters of the light-photosynthesis relationship (P sub opt = rate of light-saturated photosynthesis, and l sub k = onset of light saturation of photosynthesis) were calculated and related to the variations of temperature and light in the water column. A simple model allowed calculations of the annual production, which was estimated to be 494 g C/sq m/yr in 1983 and 547 g C/sq m/yr in 1984. A model was developed that explains the relationship between phytoplankton development and discharge: this model shows how the effect of discharge can be described by a ' dilution rate ' of the plankton growing in the river water.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Transnational modelling of the Meuse District with PegOpera simulation software

The environmental software PEGOPERA is a new tool resulting from the coupling of the PEGASE model (Planification Et Gestion de l’ASsainissement des Eaux, French acronym for planning and management of water purification) with a friendly Graphical User Interface. PEGASE is an integrated and physically based river/basin model and is devoted to the characterisation of the physico-chemical state of surface water, at the scale of a whole watershed or basin, including International River Basin District (IRBD). The aim of the model is to simulate non stationary scenarios at various scales (from a few km² to hundreds of thousands km²) while handling the entire river tree (hundreds to thousands of water bodies). The purpose of PEGOPERA is to provide the stakeholders - as regards to surface water management - with a tool dedicated to the deterministic calculation of water quality of the rivers taking into account pollutant loads and discharges. In the context of the Water Framework Directive 2000/60/EC, the international coordination between neighbouring states and regions is required. The PEGOPERA software is adapted to simulate the IRBD Meuse. Indeed: i. An integrated transnational database relevant to the entire district is available; ii. The software is operational: the Meuse application has been calibrated and validated independently on most of regional sub-basins of the district; iii. The software could be used to simulate historical and future scenarios to assess water quality improvement that may be expected after applying basic and supplementary measures. The results demonstrate the relevance of the use of this software in this kind of transnational modelling. Some regions of the International District of the Meuse are validated on historical situations. Other parts still need to be improved in terms of consolidating the input databases. Prospective scenarios implementing measures from the WFD are carried out at this District scale

Transfert du modèle mathématique PEGASE à la Direction Générale des Ressources Naturelles et de l'Environnement

Le modèle Pegase (Planification Et Gestion de l’ASsainissement des Eaux) est un modèle intégré bassins hydrographiques/rivières qui permet de calculer de façon déterministe et prévisionnelle la qualité des eaux des rivières en fonction des rejets et apports de pollution (relation pression-impact). Développé depuis la fin des années 1980 à l’université de Liège, il permet d'orienter les choix des opérateurs publics et privés en matière de gestion des eaux de surface à l'échelle des petits et grands bassins versants. La première version de Pegase a été développée à l'initiative de la Région Wallonne entre 1991 et 1993. (http://hdl.handle.net/2268/106010) En 1994, la région Wallone a confié aux développeurs une mission visant à transférer le modèle à l'administration. Outre la création d'une interface utilisateurs et le transfert du modèle proprement dit, la mission a permis de réaliser de nombreuse améliorations au modèle, principalement en ce qui concerne la représentation des rejets. Ce rapport reprend la description synthétique des tâches réalisées lors de la mission. Cinq rapports d'avancement décrivent ces tâches en détailPEGAS