| Title |
Detention Orifice Design for Non-point Source Management Using SWMM |
| Authors |
조선주 ( Seon Ju Cho ) ; 김상단 ( Sang Dan Kim ) |
| Keywords |
Detention; Non-point sources; Orifice; SWMM; Urban hydrology |
| Abstract |
This study illustrates how to design and evaluate a non-point sources management detention pond using SWMM. In particular, special attention is given to the orifice design. In SWMM, orifice properties that need to be defined include its height above the bottom of the storage unit, its type, its geometry and its hydraulic properties. Among the various characteristics of orifice, the orifice hole size which is closely related to hydraulic retention time is focused in this study. Sensitivity analysis of orifice size in annual non-point sources reduction efficiency is carried out. In addition, a methodology which can be used to design a virtual junction in SWMM has been proposed to quantify water quality improvement triggered by the detention pond installation. As a result, it is recommended that a detention outlet should be designed to be about 2 to 3 days of hydraulic retention time. |