Which risk increases when rapid subsidence occurs in a protected floodplain behind engineered levees?

💡 Explanation

When rapid subsidence occurs, the floodplain elevation decreases relative to the river constrained by the levees, increasing the possibility the flood waters will exceed the levee crest causing the flood. Therefore localized levee overtopping results, rather than reduced sedimentation, enhanced biodiversity, or enhanced recharge rates which require different conditions.

• Which outcome occurs when increased rainfall accelerates pedogenesis?
• Which consequence results when excessive floodplain construction reduces alluvial storage?
• Which mechanism causes relatively shallow sill depths at the mouth of many fjords?
• Which process is initiated at high elevations following glacial retreat from a cirque basin that exposes fractured bedrock?
• Which outcome results when levee erosion in an alluvial plain?
• Which mechanical process causes frequent shallow earthquakes along a transform plate boundary?