| Title |
Hydrologic and Hydraulic Factors Affecting the Long-term Treatment Performance of an Urban Stormwater Tree Box Filter |
| Authors |
( Franz Kevin F. Geronimo ) ; 홍정선 ( Jungsun Hong ) ; 김이형 ( Lee-Hyung Kim ) |
| DOI |
https://doi.org/10.15681/KSWE.2017.33.6.715 |
| Keywords |
Bioretention; Hydrologic and hydraulic factors; Low Impact Development; Tree box filter |
| Abstract |
Tree box filters, an example of bioretention systems, were compacted and versatile urban stormwater low impact development technique which allowed volume and water quality treatment performance to be adjusted based on the hydrologic, runoff quality and catchment characteristics. In this study, the overall performance of a 6 year-old tree box filter receiving parking lot stormwater runoff was evaluated. Hydrologic and hydraulic factors affecting the treatment performance of the tree box filter were also identified and investigated. Based on the results, the increase in rainfall depth caused decrease in hydrologic and hydraulic performance of the tree box filter including volume, average flow, and peak flow reduction (r = -0.53 to -0.59; p <0.01). TSS, organics, nutrients, and total and soluble heavy metals constituents were significantly reduced by the system through media filtration, adsorption, infiltration, and evapotranspiration mechanisms employed in the tree box filter (p <0.001). This significant pollutant reduction by the tree box filter was also found to have been caused by hydrologic and hydraulic factors including volume, average flow, peak flow, hydraulic retention time (HRT) and runoff duration. These findings were especially useful in applying similar tree box filter which may be designed by considering tree box filter surface area to catchment area of less than 1%. |