Abstract:
Hydrodynamics and water renewal of intermittent coastal streams are highly variable, at
various time scales, due to the very active morphodynamic behavior of their inlets. Due
to this strong dynamics, the pathways of water-borne materials – and the consequences
of contaminated discharges – can depend strongly on the morphology and environmental
conditions. Predicting the fate of contaminants in these systems requires coupled
numerical models accounting for the major physical and water quality processes.
We aim at improving the understanding of the impact of inlet morphology and wave
action on the pollutant and sediment pathways of these small coastal systems, based on a
suite of calibrated and validated coupled models. Two analyses, based on particle
simulations, are presented to assess sediment dynamics and pollutant pathways for
several conditions. Results show that waves have a major effect on the fate of waterborne
materials in the estuary. Wave-induced currents sweep away materials coming out
of the estuary, while wave-induced setup has a profound effect on tidal propagation,
water levels and velocities in the estuary, promoting the upstream transport of pollutants
