Estimated water balance for the proposed Haditha reservoir on the Euphrates River in Iraq

Abstract

The Iraqi Government is seriously considering the construction of a dam on the Euphrates River near the town of Haditha to better control water for irrigation on the Mesopotamian Plain, to generate hydropower and to alleviate flooding. The objective of the present study was to estimate the magnitude of possible losses from the reservoir due to seepage and evaporation. To estimate the water balance for the reservoir, all components must be estimated. Inflow was estimated based on the historical flow regime of the river but adjusted for the water requirements upstream in Syria and Turkey. Evaporation from the reservoir was estimated from pan evaporation data. Seepage losses were estimated by the Green and Ampt approach for infiltration. Complexity of the reservoir bed soil and limited data allowed only rough estimates of the water balance components. Annual expected evaporation losses from the reservoir was estimated to be 1.47 km³. The estimated seepage from the reservoir averages 0.47 km³/year for 11.5 years. Therefore, about 14% of inflow to the reservoir will be lost through seepage and evaporation for the first decade of operation. Further hydrological and geological studies are required before the feasibility of the project can be accurately assessed.