Khuzestan province has fertile plains for agriculture. In recent years, the regular supply of water in Izeh plain and Bagh Malek has been a concern, especially for agricultural purposes. With the help of a pumping station, the water of these areas reaches the heights overlooking the area from the reservoir of the Karun 3 dam and moves by gravity towards the delivery points after passing through a tunnel. The normal level of the dam during operation is 840 meters, the maximum level of the reservoir is 845 and the top level is 850 meters from the level of the Azad sea, also the minimum and maximum level of water intake from the lake of Karun Dam 3 is equal to 800 and 845 meters, respectively. Basic studies and numerical methods to achieve the goal of the current research, which is to optimize the level to which water is pumped, it was done. According to the optimizations, the lowest cost will be at the level of 970 if the tunnel level of 1000 is considered in the initial plan.