Physical Model of Hydrological Behavior of Permeable Pavements Using FlexPDE

Abstract

The increase of urbanization combined with the increase in impervious surfaces has led to an increasing frequency of flooding events in urban catchments. This context highlights the inadequacy of traditional urban drainage systems and the need for alternative solutions. Permeable pavements have proven to be a valuable low-impact development (LID) technique. They are able to retain surface runoff volumes by increasing the infiltration and evaporation processes. Even though their benefits are well known, the lack of adequate modeling tools limits their adoption. This paper presents the development of a physically based model to describe their hydrological behavior. The particularity of this partial differential equation (PDE) model is to base the parameter estimations on basic measurements. The model is calibrated and validated using measurements from a laboratory permeable pavement rig. Results demonstrate a high reliability of the model with a Nash—Sutcliffe model efficiency (NSE) value of 0.969 and 0.891, respectively, for calibration and validation. Finally, a sensitivity analysis was conducted and highlighted the influence of the hydraulic conductivity of the base layer on the performance of the structure.