| Title |
Influence of Water Supply Withdrawal on the River Flow and Water Quality |
| Keywords |
water supply withdrawal;flow analysis;river water quality;velocity distribution;RMA-2;RMA-4;하천취수;흐름해석;하천수질;유속분포 |
| Abstract |
The water quantity by intake station as well as the tributary flow discharge acting as sink or source were added to the main flow rate in the present study and RMA-2 and RMA-4 models were applied to the reach from Pal-dang dam to Jam-sil submerged weir to investigate the influence of water supply withdrawal on the river flow and water quality. The numerical results revealed that the water supply withdrawal from 5 intake stations located upstream of Jam-sil submerged weir changed the total flow rate and therby induced different hydraulic characteristics in terms of water surface elevation and velocity. The changed flow field by the inclusion of water intake quantity led to the variation of water quality. By the consideration of the water supply withdrawal, the velocity structure was significantly disturbed by the outflowing flow condition nearby Gu-ui, Ja-yang, and Pung-nap intake stations. Furthermore, the mean velocity was lowered by 25% and the stage upstream of Gu-ui station rose upto 1.5 ㎝ compared with the result by exclusion of water intake. In case of no water withdrawal, the distribution of BOD concentration was parallel throughout the domain. However, when the water withdrawal is considered, the distribution of BOD concentration nearby the Gu-ui, Am-sa, and Ja-yang station was signifiantly changed. In addition, the BOD concentration including the intake stations showed higher value at the downstream of the reach due to the loss of the discharge by water withdrawal effect. It is concluded that both the inflow and outflow discharges from tributaries and water intake stations should be included in the numerical simulation to analyze the hydrodynamic behaviors and mixing characteristics more accurately. |