The Saemangeum Basin has been subjected to water quality issues following the construction of a seawall downstream of the Mangyeong River and Dongjin River. Various structural measures have been discussed, but none have been effective so far. In this study, the change in management water level was proposed as a countermeasure, and Delft3D was used to investigate the change in water quality according to the management water levels. Future operations, including the interruption of seawater inflow, were considered. Based on three assumptions for simulating the operation of the drainage gate, the condition of Saemangeum in 2030 when the Master plan is completed was modeled. COD and T-N were selected as the pollutant indicators. The boundary conditions and numerical analysis input data were obtained by integrating actual field data and operation logs. The numerical analysis showed that the water level was more advantageous for water quality when the water level was increased by 0.10m from the current management level of EL.(-)1.5m. It was also confirmed that contaminant diffusion in Mangyung and Dongjin was not actively progressing through the new connecting canal.

No abstract