Abstract: This paper presents the slope stability analysis of Mugong landslide on the left bank of the reservoir area of Yaojiaping water control project in Hubei Province. The limit equilibrium method was used in the analysis of the reservoir under different rapid drawdown conditions after pooling. The results show that the potential landslide body is in the stable state in general. The proposed water pooling would not trigger the landslides at locations with elevation above 800.0m. In the direction of potential secondary landslide (M1) on the east side, the surficial soil layer is marginally stable under the condition that the elevation of 723.0m ~ 746.5m with a rapid drawdown from the normal pool level of 745.0m to the dead water level of 710.0m. For the surficial soil layer within this zone, it is recommended that the anti-slide caisson could be used as the mitigation method. For the potential secondary landslide of in the direction of Aimenlow (M3), the slopes within the zone between elevation 806.0m and 875.0m are basically stable. As this area in in the non-affected area of the project, the water storage of the project has no impact. The real-time slope deformation monitoring tools should be adopted. The potential sliding bodies below the elevation of 700.0m are below the dead water level, so it is considered that instability is not likely.

Key words: landslide, limit equilibrium method, engineering water reservation, mitigation