Mesopotamia, as in Antiquity, is an immense network of irrigation
canals fed by the Euphrates River.
the days of the Sumerians and Babylonians with the river's low
banks irrigation is easy. Rain was scarce, but the alluvial
soil, when watered by artificial means, proved enormously fertile.
Floods and Mongol invaders destroyed the ancient water systems,
Iraq now tries to restore them.
From the Larouse Encyclopedia of Archaeology