Which method is used to stabilize a slope affected by seepage water?

The correct method for stabilizing a slope affected by seepage water is sub-drainage. This approach involves the installation of drainage systems that manage and redirect groundwater flow, reducing pore water pressure within the slope. By effectively lowering the water levels, sub-drainage helps to enhance the stability of the soil mass, reducing the risk of landslides or slope failure.

The presence of seepage water can lead to increased soil moisture content, which negatively impacts the soil's shear strength and overall stability. Sub-drainage systems, such as perforated pipes or horizontal drains, are designed to mitigate these issues by allowing excess water to escape from the soil structure. This not only aids in lowering water levels but also helps to maintain optimal moisture conditions within the soil, promoting stability over time.

Other methods, while useful in different circumstances, do not specifically address the issues posed by seepage. Chemical stabilization typically involves adding binding agents to increase soil strength but may not effectively tackle the problems caused by water infiltration. Slope reduction or flattening modifies the geometry of the slope but often does not directly address the underlying hydrogeological issues. Structural solutions, such as retaining walls, can provide support but might not resolve the problem of excess water within the slope. In