Towards the production of guidelines to support the design of stormwater management practices for on- site pollution control ; Vers la production de recommandations pour le dimensionnement de techniques alternatives permettant une maîtrise à la source des flux de polluants

International audience ; This paper presents the application of a conceptual hydrological model (developed in previous studies) for the evaluation of different stormwater management strategies for on-site pollution control. A meta-modelling approach is first adopted to emulate the original model at a low computational cost and to investigate the influence of the design of stormwater source-control systems in terms of pollutant removal efficiency from a large number of simulations. The analysis is based the construction of " sizing diagrams " relating the performance of the facility to some design parameters and illustrates the applicability of the model for the production of simple design tools. A more detailed assessment of the behavior of the source control system is later conducted for a limited number of design scenarios, so as to better understand how stormwater management strategies affect the distribution of pollutant discharges and to verify that selected configurations result in a correct hydrological functioning of the facility. The analysis primarily indicates that noticeable load reductions may be achieved through the infiltration of a small fraction of runoff. The selection of configurations producing in satisfactory pollutant removal efficiencies may however result in a failure of the facility for low permeability soils, due to a limited drainage capacity. These results therefore indicate that the design of source control systems should not solely be based on pollution control criteria and that their hydrological functioning should also be investigated. ; L'objectif de cette étude est d'illustrer l'intérêt d'une chaine de modélisation, développée dans des travaux antérieurs, pour le dimensionnement des pratiques de gestion à la source des eaux pluviales urbaines. Une approximation de la chaine de modélisation par un méta-modèle est dans un premier temps utilisée afin d'évaluer l'incidence du dimensionnement des techniques alternatives pour la maîtrise des flux de polluants pour un grand nombre de ...