Why did Sumerians build leevees?

Sumerians built levees to control the flooding of the Tigris and Euphrates rivers, which were prone to seasonal floods. These earthen barriers helped to protect their agricultural fields and settlements from water damage, ensuring a stable food supply. Additionally, levees allowed for better irrigation management, facilitating the cultivation of crops in the arid climate of Mesopotamia. Overall, levees were crucial for the Sumerians' agricultural success and urban development.