The magnitude and extent of damage caused by a dam break to the downstream area depends heavily on the dam breaking rate and degree,which determines the flow discharge through the breach and its spreading speed in the downstream valley.

• 大坝溃决的速度和程度很大程度上决定了溃坝洪水波的大小及其传播速度 ,继而对下游受灾程度和范围产生巨大影响。