Physical Model Tests to investigate the Hydraulic Efficiency of Street Inlets

Abstract

According to current climate projections the number of heavy rainfall events causing flash floods will increase in the near future. The dimensioning of the canalization in accordance to these events is not reasonable. Therefore the accumulating storm water needs to be discharged at the ground surface. Recent developments in modelling consider the interaction between canalization- and surface-discharge, allowing the exchange of storm water at predefined spots. In reality these spots are the street inlets, which gather the storm water and convey it into the drainage system. In order to be able to depict street inlets in modelling precisely it is necessary to have profound knowledge about their performance dependent of the longitudinal and transversal slope of the street and the occurring surface flow. Physical model tests are run at the University of Wuppertal to investigate the performance of street inlets typically used in Germany. First results deliver efficiencies up to 70 % or less depending on the street geometry and surface flow.