An Experimental Study of the Retention Effect of Urban Drainage Systems in Response to Grate Inlet Clogging

The rainfall drainage characteristics of urban areas result in more surface runoff compared to soil surfaces. Conventional Urban Drainage Systems, CUDs, have disadvantages when managing this surface runoff, leading to urban water circulation issues such as flooding and depletion of groundwater. The performance of CUDs varies significantly depending on the clogging of grate inlets with various debris and shapes. To address these disadvantages, Sustainable Urban Drainage Systems, SUDs, have been proposed. This study compares the drainage efficiency of the two systems; using a physical model with an artificial rainfall simulator, an experimental study was conducted with respect to clogging type, clogging ratio, and rainfall intensity. Comparative analysis of peak flow rates and the peak time demonstrates the advantages of IRDs. As a result, IRDs are applicable to the mitigation of urban water circulation problems such as inundation.