In this study various investigations were carried out to analyze the causes of leakage for 20 years on the slope of the downstream side of the dam during the ○○ dam precision safety diagnosis. Analysis showed that the possibility of underground water flowing through the valley section of the mountain area extremely low, and that direct leakage of the reservoir's freshwater was confirmed as the main leakage path.
This study compared the result applying two analysis methods based on Newmark Sliding Block theory to calculate permanent displacement that is an estimating factor for seismic safety of Fill Dam. It was analyzed FEM numerical coupled-analysis and Makdisi-Seed method. The permanent displacement for the body of dam during earthquake indicated similar displacements with each of them at the same seismic load.