H2O will become the main strategic resource of this century In an era distant from us, five thousand years BC, when the Sumerian civilization was taking shape in the lower reaches of the Euphrates, life there depended primarily on the availability of water. The river was divided into channels, which often changed their course, and where water used to flow, swamps or lifeless clay soils appeared. Therefore, control over water sources, canals and dams was vital for the Sumerians.