Numerical Modeling of Water Levels on Pavements under Extreme Rainfall

Abstract

This study presents an advanced model for calculating water levels on impervious areas. The approach combines information about rain intensity and flow condition to dynamically determine overland roughness values. When water levels on profiled surfaces of less than 500 m are calculated, the full dynamic wave approximation is necessary because the transition of flow differs compared to kinetic wave theory at the beginning of the runoff event. The application of the model to a civil airport demonstrates how the frequency of critical water levels changes when the cutting of grooves into the runways is considered. The local storm water characteristics are defined by heavy convective precipitation during summer. A critical event was presumed when the water level may cause aquaplaning. The results present a reduction of the number of critical events during a period of 10 years by 68%, even without recognizing the additional friction by the grooves. If increasing friction was included, the remaining frequency would be 0.2 times per year.