Abstract

The look for the new water resources and the optimal using of available water is very important because of high change in the climate of the earth, the dry wave in the region as well as the decreases of the water inflow to the Euphrates and the tigress river because of the building of the dams upstream the basin in Turkey and Syria.
In the present study, four biggest catchments area in the Iraqi western desert (wadi Horan, wadi AlGhadaf, wadi Ubayiad, wadi Tubul) were selected to study the hydrologic properties to determine the best region for the water harvesting because these areas include the most water harvesting project such as the small dams.
Present hydrologic study was depended on the available data to determine the amount of runoff that can be harvested according to measuring data of metrological station in the region with the method of hydrograph for analysis.
For the period (1971-1976) the study showed wadi Al-ghdaf is the best region for water harvesting according to the number of floods to the cathment area (44 floods) with water volume (1047*106m3), and the average water harvesting (7098.64 m3/km2). The second is wadi Horan the number of floods to the cathment area (33 floods) with water volume (2033.29*106m3), and the average water harvesting (6115.16 m3/km2). Then wadi al Ubyaid number of floods to the cathment area (21 floods) with water volume (405.197*106m3) and the average water harvesting (2493.52 m3/km2). The last one is wadi Tubul with number of floods to the cathment area (18 floods) with water volume (909.36 and the average water harvesting (2231.6 m3/km2)*106m3)