Jean-François Deliège

PEGASE, an integrated river/basin model dedicated to surface water quality assessment: application to cocaine

Abstract The scientists of the Aquapôle of the University of Liège have been involved in environmental modeling for more than 20 years. Among other, its current R&D unit focuses on the compartment of surface water, and – for modeling processes – is specialized on the water quality. One of its environmental models, called PEGASE (Planification Et Gestion de l’ASsainissement des Eaux), French acronym for “Planning and management of water purification” is devoted to the modeling of the environmental state of surface water, at different scales from small watersheds (10 km2) and basins up to entire transnational Districts (more than 100.000 km2). The software is used operationally by several administrations (Agencies and Ministries) mainly through Europe (France and Benelux, Germany …), and several calculations have also been performed at international District levels for international commissions (Scheldt, Meuse, Moselle …). Recently, the PEGASE model has been adapted to describe the cocaine’s behavior (using a stable metabolite of the cocaine in the environment: the benzoylecgonine) in waste water, waste water treatment plants (WWTP) and surface water. The cocaine is newly described in the model as an additional micropollutant (Pegase already treats numerous heavy metals), thanks to the implementation of new state variable equations and their specific parameterizations. At a first stage, only the urban sources (releases associated to the consumption by inhabitants) were considered as the industrial releases and the soil loads are assumed to be negligible. Simulations of benzoylecgonine have been done in the Walloon and Flemish regions, where many measurements from the COWAT project were available. These first results are showing a good agreement between calculated and measured values. This ability of the model to simulate the fate of the cocaine derivatives in surface waters should be continued and extended to other metabolites.

Sea Air Land Modeling Operational Network

The purpose of the SALMON project is to develop a single model from three previously existing models (ocean, river and ground-water) for the description of environment quality in a whole system of regional scale including marine, river, groundwater and atmospheric inputs. The connection of the different models is done through a specific interface, a junction, designed to allow the data exchange between models based on different numerical methods. The software is developed on IBM RS/6000 computers (the SP2 parallel machine).