Which hazard increases significantly after rapid drawdown from a dam reservoir situated on karst bedrock?

💡 Explanation

A rapid water level decrease destabilizes soil structures overlaying soluble rock due to decreased pore pressure support; this triggers a process called suffosion. Because of suffosion, finer soil particles migrate into bedrock fissures, therefore undermining surface stability leading to sinkhole collapses rather than other issues.

• Which outcome occurs when sediment supply decreases significantly in a coastal area with a longshore current?
• Which consequence occurs when prolonged river sedimentation exceeds levee subsidence in a delta?
• Which mechanism causes increased flood risk when building impermeable surfaces on an alluvial fan?
• Which mechanism prevents constant seismic activity along a transform fault like the San Andreas?
• Which slope failure accelerates when freeze-thaw cycles increase water content in permafrost-affected soils?
• Which mechanism initiates alluvial fan formation when a mountain stream reaches a broad valley?