A hydrological model to study the performance and irrigation of stormwater facilities Un modèle hydrologique pour étudier la performance et l’irrigation des installations d'eaux pluviales

Urban development can produce great impacts on local hydrology reducing infiltration and evapotranspiration, and increasing direct runoff volumes. Runoff control practices are implemented at local scales to control flow discharges and preserve the hydrological cycle. These techniques usually have green infrastructure therefore the application in semiarid and Mediterranean regions requires accounting for aspects related to maintenance of green areas, such as the irrigation needs and the selection of the vegetation. This study develops the Integrated Hydrological Model at Residential Scale, which allows evaluating in a continuous manner the rainfall-runoff processes and stormwater control at residential scales, together with the irrigation of green areas and the vegetated LID’s involved. The model simulates surface and subsurface hydrological processes and accounts for the soil water content’s dynamics. Different components of the model were tested using laboratory and numerical experiments, and then an application to a case study was carried out. The model identifies significant differences in the performance of a rain garden with different vegetation, climate and irrigation practices, and provides a good insight for the maintenance needs of green infrastructure for runoff control.