The groundwater level fluctuation was studied in a complex geological
setting region where a frequent landslide is observed in a rainy season. Steady
and transient states of flow are modeled with different hydrogeological parameters.
The models are calibrated to satisfy the observed field conditions and expected
results from thescientific point of view. The results reveal that the groundwater level
fluctuation and flow direction in the region are complex. In limited areas, the
fluctuation of groundwater is significant from season to season while in others
the level remains stable in all seasons of the year. Following that, the result
of groundwater flow model was exported to GeoStudio to simulate the slope
stability of selected slope. The factor of safety was calculated using Slope/W.
The effect of pore-water on thefactor
of safety was cross-checked by remodeling the slope without water. The results
and sensitivity analysis of slope stability confirm that the rise of
groundwater level decreases the factor of safety significantly only on critical
slope section.
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