How did mesopotamian irrigation systems allow civilization to develop?

Irrigation systems gave them water and controlled the floods of the rivers. without the irrigation systems the floods would have been detrimental to their societies. they collected water which they could use for farming and for the first time, there was a surplus of crops. the crops gave them food and also things to trade which helped their economy.

More than 4 million enslaved hunan beings in the south and they touched every aspect of the regions social, political and economic life.