This study aimed to identify the hydrologic characteristics and investigate the effect of hydrological flow changes for the Adhaim tributary by updating the information of watershed hydrology and examined the possibility of changing the spillway dam from being ungated to a controlled gated spillway to reduce the impact of water releases on the Tigris River and Baghdad City during the flood season. In addition, an attempt is made to store as much water as possible to benefit the summer growing season by supplying water to irrigation projects downstream of Adhaim Dam. The results indicated that if the gates were installed at the level of 135 m above sea level, flood waves with a probability of 1/100 can be controlled and safely flow to the Tigris River at ~200 m3/s. The gates would also increase the capacity of the Adhaim reservoir. Different options for controlling the gated spillway are suggested, and the designers can choose one of them.

The increasing of temperature with reduction of rainfall in dry season led to reduce water areas which cause reduce the cultivation areas in Iraq and other countries. Effecting of drought causing negative action on crop productivity. The irrigation water shortage will impact on crops by stress of water as well water decreasing will increase salt concentration that will increase the salt stress cause influence on yield of crops. This research will study of stress by decreasing of water (deficit irrigation) on production of okra crops with both use subsurface water retention techniques (SWRT) and without use SWRT, then estimation differences after that calculate affection of salt on crop. The research was done in Babylon governorate in Al-Hindiya Barrage. The treatments A1 used drip irrigation system with SWRT technique and used deficit irrigation in some times, while A2 used trickle irrigation without SWRT and use deficit irrigation in some times. The results of treatment A1 showed the amount of applying water reduced to 7% than A2. Whereas the number of irrigations of A1 equal to A2. The yield of crop of A1 was more than of A2 by 15 %. The actual yield of A1 was impacted by water stress and salt were 0.01 kg/m2 and 0.011 kg/m2 respectively. The actual yield of A2 which impacted by water stress and salt were 0.079 kg/m2 and 0.085 kg/m2, respectively. The yield in A1 with SWRT and without stress and the yield of A2 without SWRT and without stress showed percent of increasing of 2.3%. The SWRT technique helps to stress resistance and drought resistance by using okra of loam soil.