The flood is uncontrolled and unthinking, and so can't be blamed for it's path of destruction. It is the fickle levee which Led Zeppelin chides and hates in "When the Levee Breaks". [Personifying] the levees as mean and vindictive, the song tells a sad story of love and livelihood lost to disaster... but a glimmer of hope for detachment and new life is allowed to shine through.