Why did the farmers of Ancient Egypt dug canals and build dams?

Ancient Egypt was an agricultural country and yields depended on the amount of water in the Nile. This river flooded every year at about the same time, making the desert land fertile. To better distribute the waters of the Nile during the flood season, the Egyptians dug canals and built aqueducts. Thus, it was possible to divert water much further from the river itself, and irrigate more area, and lower the level of the river in case of flooding. The deep pools made it possible to better keep the water from evaporation.