J Korean Soc Environ Eng. 2015; 37(10): 563-572.
Published online 2015 October 31.
Modeling the Flushing Effect of Multi-purpose Weir Operation on Algae Removal in Yeongsan River
1K-water Institute, K-water
2Water Resources Operations Center, K-water
Received 2015 September 25; Accepted 2015 October 28.
ABSTRACT
The purpose of this study was to model the effect of flushing discharge on algae removal by multi-purpose weir operation in Yeongsan River (Seungchon Weir) using a 3-dimensional (3D) model. The chlorophyceae Eudorina sp. formed bloom in May 2013. Flushing discharge was conducted in two different ways for algal bloom reduction. To elucidate the spatial variability, a high-resolution 3D model, ELCOM-CAEDYM, was used to simulate the spatial variations of water quality and chl-a over a month. The results showed that ELCOM-CAEDYM could reproduce highly spatially resolved field data at low cost, and showed very good performance in simulating the pattern of algal bloom occurrence. The effect of each flushing discharge operation was analyzed with the results of modeling. The results of case 1, flushing discharge using an open movable weir, showed that the algal bloom between the Seochang Bridge and the Hwangryong River junction is rapidly flushed after operating the movable weir, but the residual algae remained in the weir pool as the discharge decreased. However, the results of case 2, fixed weir overflow with a small hydropower stop, showed that most of the algae was removed after flushing discharge and the effect of algae removal was much bigger than that in case 1, as per modeling results and observed data.
Keywords :
Flushing Discharge, Multi-purpose Weir, Algae Removal, Eudorina sp., ELCOM-CAEDYM
