How did farmers in Sumer use dikes?

Farmers in Sumer used dikes to control the flow of water from the Tigris and Euphrates rivers, protecting their fields from flooding during heavy rains and ensuring a stable water supply for irrigation. By building these earthen barriers, they could direct water to their crops, enhancing agricultural productivity in the arid Mesopotamian climate. This system of water management was crucial for supporting Sumer's growing population and complex society.