Unexpected spatial impact of treatment plant discharges induced by episodic hydrodynamic events: Modelling Lagrangian transport of fine particles by Northern Current intrusions in the bays of Marseille (France)
|Author(s)||Millet Bertrand1, 2, Pinazo Christel1, 2, Banaru Daniela1, 2, Pages Remi1, 2, Guiart Pierre1, 2, Pairaud Ivane3, 4|
|Affiliation(s)||1 : Aix Marseille Univ, CNRS, Mediterranean Inst Oceanog UM 110, IRD, Campus Luminy, Marseille, France.
2 : Univ Toulon & Var, CNRS, Mediterranean Inst Oceanog UM 110, IRD, La Garde, France.
3 : Inst Francais Rech Exploitat Mer, Lab Environm Ressources Prov Azur Corse, La Seyne Sur Mer, France.
4 : Inst Francais Rech Exploitat Mer, Lab DYNECO DHYSED, Plouzane, France.
|Source||Plos One (1932-6203) (Public Library Science), 2018-04 , Vol. 13 , N. 4 , P. e0195257 (25p.)|
|WOS© Times Cited||17|
|Note||S1 Dataset. Source files of computed particle trajectories (ZIP file). S1A and S1B (netcdf) correspond to the ICHTHYOP computations of June 2008 and October 2011, respectively. https://doi.org/10.1371/journal.pone.0195257.s001|
Our study highlights the Lagrangian transport of solid particles discharged at the Marseille Wastewater Treatment Plant (WWTP), located at Cortiou on the southern coastline. We focused on episodic situations characterized by a coastal circulation pattern induced by intrusion events of the Northern Current (NC) on the continental shelf, associated with SE wind regimes. We computed, using MARS3D-RHOMA and ICHTHYOP models, the particle trajectories from a patch of 5.104 passive and conservative fine particles released at the WWTP outlet, during 2 chosen representative periods of intrusion of the NC in June 2008 and in October 2011, associated with S-SE and E-SE winds, respectively. Unexpected results highlighted that the amount of particles reaching the vulnerable shorelines of both northern and southern bays accounted for 21.2% and 46.3% of the WWTP initial patch, in June 2008 and October 2011, respectively. Finally, a conceptual diagram is proposed to highlight the mechanisms of dispersion within the bays of Marseille of the fine particles released at the WWTP outlet that have long been underestimated.