资源环境科技发展态势分析平台

Stormwater detention basins are significant components for the sustainable management of urban stormwater, aiming to control stormwater quantity (prevent from flooding) and quality (trap particulate pollutants by settling). The design and management of such facilities need knowledge of the hydrodynamic characteristics and the sedimentation zones for cleaning purposes. Large-scale particle image velocimetry (LSPIV), mostly applied in riverine environments, has been proven as a low-cost, highly efficient, and convenient image-based methodology for surface velocity measurement. In this study, LSPIV technology is employed to investigate free surface velocity in a field stormwater detention basin. The method is first evaluated by comparing its results with those obtained by acoustic Doppler velocimeter at pilot scale. Then, the technique is applied to better understand the main flow field and to explain spatial sediment distribution within an extended stormwater detention basin. Results illustrate two main flow patterns, which are consistent with observations and preliminary simulated results. LSPIV-based free surface velocity field measurements can be used to evaluate numerical models and as a support to predict sediment deposition zones in stormwater detention basins and to help for their retrofit and management.