What does the levee in Grapes of Wrath symbolize?

In "The Grapes of Wrath," the levee symbolizes both physical and social barriers. It represents the struggle against nature and the efforts to control the land, as well as the broader theme of human resilience in the face of adversity. Additionally, the levee serves as a metaphor for the societal divisions and inequalities that exist, highlighting the plight of the dispossessed and the challenges they face in seeking stability and safety.