Alternative Approach to Evaluate Sedimentation Performance of Stormwater Detention Basins Using a Nondimensionalized Time Scale

Abstract

To evaluate sediment removal in dry detention basins, one of the most frequently used Best Management Practices (BMPs), a particle pathline model using plug flow assumption was proposed in a previous study. The model requires numerical integration, thus it may not be convenient for quick evaluation and design of detention basins. To overcome the difficulty a simpler continuous stirring tank reactor (CSTR) model is proposed and used to compare outflow Suspended Sediment Concentrations (SSCs) from different size storms using a nondimensionalized time scale. The CSTR model satisfactorily predicts sediment removal and outflow SSC measured using a physical model. The paper presents the time nondimensionalization and CSTR model application processes and discusses the critical characteristics of the proposed models.