수치모형에 의한 섬진강 하구 염수침입 평가

Abstract

Of the rivers in Korea, only Seomjin River and Han River maintain natural estuaries. However, the development of large-scale industrial complexes around the Seomjin River estuary and in the Gwangyang Bay area has resulted in many changes to the river bed and seabed topography in this area. In particular, the lowering of the riverbed, the raising of the sea level, and the reduction in the flow rate within the upstream basin of Seomjin River due to development projects have exposed the Seomjin River estuary to a saltwater environment. In this study, the tidal currents, river runoff, and riverbed topography were simulated in an EFDC model (Environmental Fluid Dynamics Code) in order to reproduce saltwater intrusion patterns, and the degree of saltwater intrusion was evaluated by analyzing its longitudinal distribution. It was found that the saltwater intrusion was more significantly affected by changes in the Songjeong flow than by changes in the Daap water intake. Based on changes in the Songjeong flow, the maximum and minimum saltwater intrusion was 24.1 km and 22.2 km, respectively. In addition, saltwater intrusion varied between4.6-7.0 km, increasing by 52.17% during the spring tide period compared with the neap tide period.