Experimental investigation of rainfall-watershed-bioretention system


Urban Transitions Global Summit 2016, Shanghai, China, 5 - 09 September 2016, pp.44

  • Publication Type: Conference Paper / Summary Text
  • City: Shanghai
  • Country: China
  • Page Numbers: pp.44
  • Istanbul University Affiliated: Yes


The land development and increase in urbanization in a watershed affect both surface water and groundwater resources. Urbanization results in an increase in surface runoff and volume of water collected downstream of the watershed. Furthermore, excess runoff accelerates pollutant transport and causes water pollution in water resources. Preserving and recreating natural landscape features and minimizing effective imperviousness to create functional and appealing site drainage, which treats storm water as a resource rather than as a waste product, are intended by implementing Low Impact Development (LID). There are several LID storm water BMPs such as bioretention facilities, rain gardens, storm water wetlands, vegetated rooftops, rain barrels, vegetative swales, and permeable pavements. Bioretention type of Low Impact Developments (LIDs) have been implemented to diminish adverse effects of urbanization such as flood by reducing peak flows on surface and thus managing storm water runoff. The objective of this study is to investigate the hydrological performance of bioretentions, which may also be considered as a small size local constructed wetland, by conducting experimental analyses under various rainfall intensities and durations. For this purpose, an experimental setup called Rainfall-Watershed-Bioretention (RWB) System is constructed which involves an artificial rainfall system, drainage area, and four bioretention columns with different soil textures and organic content. Inflow rate at the entrance of bioretentions and ponding depth on bioretention columns are measured during selected artificial rainfall events and durations. In addition, the outflow rate at the exit of bioretention columns is measured to understand the role of soil types in hydrological behavior of bioretention columns. Experimental results show that different soil types and organic content under various rainfall intensities and durations affect hydrological performance of bioretentions considerably.