Modelling a Severe Transient Anoxia of Continental Freshwaters Due to a Scheldt Accidental Release (Sugar Industry)
Aline Grard,
Etienne Everbecq,
Pol Magermans,
Jean-François Deliège
Affiliations
Aline Grard
FOCUS Research Unit—Freshwater and OCeanic Sciences Unit of Research, PeGIRE Laboratory, Aquapôle Research Center, Department of Biology Ecology and Evolution, Faculty of Sciences, Campus Sart-Tilman, University of Liège, Allée de la Découverte 11, Building B53, Quartier Polytech 1, 4000 Liège, Belgium
Etienne Everbecq
FOCUS Research Unit—Freshwater and OCeanic Sciences Unit of Research, PeGIRE Laboratory, Aquapôle Research Center, Department of Biology Ecology and Evolution, Faculty of Sciences, Campus Sart-Tilman, University of Liège, Allée de la Découverte 11, Building B53, Quartier Polytech 1, 4000 Liège, Belgium
Pol Magermans
FOCUS Research Unit—Freshwater and OCeanic Sciences Unit of Research, PeGIRE Laboratory, Aquapôle Research Center, Department of Biology Ecology and Evolution, Faculty of Sciences, Campus Sart-Tilman, University of Liège, Allée de la Découverte 11, Building B53, Quartier Polytech 1, 4000 Liège, Belgium
Jean-François Deliège
FOCUS Research Unit—Freshwater and OCeanic Sciences Unit of Research, PeGIRE Laboratory, Aquapôle Research Center, Department of Biology Ecology and Evolution, Faculty of Sciences, Campus Sart-Tilman, University of Liège, Allée de la Découverte 11, Building B53, Quartier Polytech 1, 4000 Liège, Belgium
Most anthropogenic pollution can be controlled, such as domestic and industrial releases, loads from agriculture, etc. However, some of them, which are associated to illegal discharges, industrial accidents, etc., are more difficult to forecast. This study was performed on the Tereos sugar industry accident that occurred during the night of 9 April 2020, when 88,000 cubic meters of effluents loaded with organic matter discharged in the Scheldt River (a 350 km long transnational river that flows through Northern France and Western Belgium). The accident had dramatic consequences on the receiving watercourse, over 120 km downstream. Fish mortalities have been observed and severe deoxygenation, reaching zero concentration in dissolved oxygen, have impacted river chemical quality. The objective was to understand and describe the dynamics of the chemical pollution and its propagation along the transboundary hydrographic network of the Scheldt. A method based on the processes of organic matter degradation in the river ecosystem was enhanced. It is demonstrated that the accident is doubtless the cause of the water column deoxygenation. This paper shows how the water quality modelling can help to understand and therefore to prevent the consequences of accidental pollution on a river network.
