Hydrologic and water quality performance of a laboratory scale bioretention unit  

作　　者：Jun Xia Hongping Wang Richard L. Stanford Guoyan Pant Shaw L. Yus 

机构地区：[1]State Key Laboratory of Water Resources ＆ Hydropower Engineering Sciences, Wuhan University, Wuhan 430072, China [2]Key Laboratory of Water Cycle ＆ Related Land Surface Processes, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China [3]Department of Environmental Engineering, School of Resources and Environmental Science, Wuhan University, Wuhan 430079, China [4]ATR Associates, Inc., Strasburg, VA 22657, USA [5]Department of Civil and Environmental Engineering, University of Virginia, Charlottesville, VA 22903, USA

出　　处：《Frontiers of Environmental Science & Engineering》2018年第1期159-167,共9页环境科学与工程前沿（英文）

摘　　要：A bioretention unit （BRU） or cell is a green infrastructure practice that is widely used as a low impact development （LID） technique for urban stormwater management. Bioretention is considered a good fit for use in China＇s sponge cit.y construction,projects. However, studies on biooretention design, whichincorporates site-specific environmental and social-economic conditions in China are still very much needed. In this study, an experimental BRU, consisted of two cells planted with Turf grass and Buxus shfica,was tested with eighteen synthesized storm events. Three levels （high, median, low） of flows and concentrations of pollutants （TN, TP and COD） were fed to the BRU and the performance of which was examined. The results showed that the BRU not only delayed and lowered the peak flowsbut also removed TN, TP and COD in various ways and to different extents. Under the high, medium and low inflow rate conditions, the outflow peaks were delayed for at least 13 minutes and lowered at least 52%. The two cells stored a maximum of 231 mm and 265 mm for turf grass and Buxus sinica, respectively. For both cells the total depth available for storage was 1,220 mm, including a maximum 110 mm deep ponding area. The largest infiltrate rate was 206 mrn/h for both cells with different plants. For the eighteen events, TP and COD were removed at least 60% and 42% by mean concentration, and 65% and 49% by total load, respectively. In the reservoir layer, the efficiency ratio of removal of TN, TP and COD were 52%, 8% and 38%, respectively, within 5 days after runoff events stopped. Furthermore, the engineering implication of the hydrological and water quality performances in sponge city construction projects is discussed.A bioretention unit （BRU） or cell is a green infrastructure practice that is widely used as a low impact development （LID） technique for urban stormwater management. Bioretention is considered a good fit for use in China＇s sponge cit.y construction,projects. However, studies on biooretention design, whichincorporates site-specific environmental and social-economic conditions in China are still very much needed. In this study, an experimental BRU, consisted of two cells planted with Turf grass and Buxus shfica,was tested with eighteen synthesized storm events. Three levels （high, median, low） of flows and concentrations of pollutants （TN, TP and COD） were fed to the BRU and the performance of which was examined. The results showed that the BRU not only delayed and lowered the peak flowsbut also removed TN, TP and COD in various ways and to different extents. Under the high, medium and low inflow rate conditions, the outflow peaks were delayed for at least 13 minutes and lowered at least 52%. The two cells stored a maximum of 231 mm and 265 mm for turf grass and Buxus sinica, respectively. For both cells the total depth available for storage was 1,220 mm, including a maximum 110 mm deep ponding area. The largest infiltrate rate was 206 mrn/h for both cells with different plants. For the eighteen events, TP and COD were removed at least 60% and 42% by mean concentration, and 65% and 49% by total load, respectively. In the reservoir layer, the efficiency ratio of removal of TN, TP and COD were 52%, 8% and 38%, respectively, within 5 days after runoff events stopped. Furthermore, the engineering implication of the hydrological and water quality performances in sponge city construction projects is discussed.

关 键 词：Bioretention unitSponge cityStormwater runoffPeak reductionPollutant removal 

分 类 号：TU984.313[建筑科学—城市规划与设计] TE626.3[石油与天然气工程—油气加工工程]