Which risk increases when a river's flow encounters highly erodible alluvial sediments during seasonal floods?

💡 Explanation

When a river encounters erodible alluvium during flooding, enhanced lateral erosion via hydraulic action occurs because the saturated sediments offer minimal resistance, leading to accelerated bank erosion and channel migration. Therefore rapid channel migration results, rather than enhanced sedimentation, reduced recharge, or increased delta formation, which require specific sediment transport or base level conditions.

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