The electric-hydraulic dredger is the major construction ship during the land reclamation project which has advantages of shallow draft, flexibility, lower cost and great adaptability. With the continuous expansion of the inning project, the sand-blowing distance required increases, but the blowing distance of the electric-hydraulic dredger itself cannot meet the construction needs. In order to solve the technical difficulty of the long-distance construction, we increase the relay pump along the pipeline. Meanwhile, according to the auxiliary loader project of the Fifth Commercial Aircraft Runways in Shanghai Pudong airport , we obtain the proportional relationship between the pump power and the long-distance pipeline under the condition of the fine sand. It can not only determine the reasonable position of the relay pumps to solve the technical difficulties of the long-distance construction, but also cut down the construction cost, and improve the efficiency of construction efficiency.