Investigation of the evolution of the irrigation system in ancient Mesopotamia using a hydraulic model

Abstract

In this study a simplified model of the rivers Tigris and Euphrates during the Uruk period (3500-3100 B.C.) was created in order to define the hydraulic behaviour of the rivers in ancient Mesopotamia. The model was used to test the effect of a number of factors on the water-level of the river system. Especially, the role of the development of settlements in the Mesopotamian valley and the way the irrigation system was operated was examined. Also, physical processes such as the avulsion of the secondary branches of the two rivers was taken into account.
According to the results of the simulation Euphrates is much more sensitive to an increase in water demand than Tigris. However, when two branches in the upper part of the river are closed the problem of low water level in Euphrates is solved. Furthermore, the development of settlements and irrigation nodes in ancient Mesopotamia, at the lower part of the valley, has as a result a lack of sufficient water even at the early stages of societal development. On the other hand, Euphrates does not seem to be so sensitive to an increase in water demand in the upper part of the valley.