Based on hydraulic model tests of a reinforcement project, the water flow pattern, velocity distribution, maximum depth-averaged velocity of a typical section, and scouring characteristics downstream of the sluice were measured, and the cause of water flow pattern deterioration and scour severity under the design scheme were analyzed. The cause is considered to be the change of the flow boundary condition after reinforcement of the downstream wing wall, which concentrates the main flow downstream of the sluice, increases the velocity locally, and intensifies scouring. Through comparison of different energy dissipation and scour prevention schemes, the method of using partition piers to eliminate the flow accumulation is put forward. Partition piers can eliminate the main flow extrusion by the boundary, improve the flow pattern downstream of the sluice, homogenize the velocity distribution downstream of the sluice, reduce the maximum velocity of the river bed, and decrease scour downstream of the sluice. The partition piers have a simple structure and construction.