The objective of this paper is to link the second phase with the third phase of the man-made river project at the connecting point near the SEDADA area. The flow rate in the second phase of the project will increase from 1.666 million cubic meters of water per day to 2.646 million cubic meters of water per day, by increasing 0.98 million cubic meters of water from the first phase through the third phase. It was necessary to study the effect of this increase in the flow rate and how to obtain the optimum way to transfer this quantity of water in terms of hydraulic and specifically the effect of change in pressure and pipe diameters. Therefore, the options studied which were proposed, namely the construction of the ALKHOMS pumping station, the linear pipeline, and the independent pipe line. The analysis is carrying by applying COLEBROOK-WHITE equation with using excel program to evaluate the hydraulic gradient at each point of study along the pipe line. The Optimum flow rate and pipe diameters was found are 30.625 m3 / sec and (3.4m-3.8m) respectively, which allows the water flow from the point of connection to the TAMALLAH  (RS) with natural flow.