Application Effect of Water Quality HSPE & EPDC Models Used to Improve Water Quality in G lake

In order to predict changes in water quality from pollutants and sewage treatment plants in Lake G located in Y-si, Gyeonggi-do, the water quality improvement project was carried out step by step using the HSPE model and EFDC (Environmental Fluid Dynamic) model. The data used in this study were carried out by correcting the model using water quality data from 2015 to 2017, and the impact was determined by investigating the sources of contamination flowing into Lake G, the subject of this study. Water quality improvement project items were applied to reduce discharge and concentration at G sewage treatment plant adjacent to G lake by 20 % compared to the current level, implement non-point pollution source reduction project, and implementation of G lake ecological river restoration project.According to the forecast, it is expected to have a great effect on the improvement of water quality by the expansion of facilities at sewage treatment plants into Lake G, maintenance of sewage pipes, non-point pollution sources, and restoration of ecological river restoration. It was set as COD and T-P as the representative items of water quality, and in case of irresponsibility, the water quality is continuously deteriorating every year. After implementing each step, the algae phenomenon of Lake G is expected to be reduced and the water quality improvement effect is expected.