Modelling subsurface storm flow with the Representative Elementary Watershed (REW) approach: application to the Alzette River Basin

摘要

A new domain, the macropore domain describing subsurface storm flow, hasbeen introduced to the Representative Elementary Watershed (REW) approach.The mass balance equations have been reformulated and the closure relationsassociated with subsurface storm flow have been developed. The model code,REWASH, has been revised accordingly. With the revised REWASH, arainfall-runoff model has been built for the Hesperange catchment, asub-catchment of the Alzette River Basin. This meso-scale catchment ischaracterised by fast catchment response to precipitation, and subsurfacestorm flow is one of the dominant runoff generation processes. The model hasbeen evaluated by a multi-criteria approach using both discharge andgroundwater table data measured at various locations in the study site. Itis demonstrated that subsurface storm flow contributes considerably tostream flow in the study area. Simulation results show that dischargesmeasured along the main river course are well simulated and groundwaterdynamics is well captured, suggesting that the model is a useful tool forcatchment-scale hydrological analysis.