The operation of large hub groups in the main and tributaries of the upper reaches of the Yangtze River led to the great changes in water and sand conditions. In addition，man-made sand mining activities before 2017 led to the large-scale evolution of the channel in the Dongxikou group of shoals in the Yangtze River upstream.The changes of splitting ratio and sand ratio in left and right branches，which can make the left channel with relatively straight shape meet the possibility of navigation during the dry season. We adopt the physical model of Dulizi-Dongxikou waterway to study the channel maintenance measures of the left channel under the new conditions，take 8 groups of flow rates from the dry period to the flood period as the control conditions，measure and analyze the changes of the diversion ratio，water level，velocity，direction and flow pattern of the left and right channel before and after the scheme and simulate the process of the ship going up and down the shoal. The results show that the recommended maintenance scheme has little effect on the upstream Doulizi rapid. In each period，the flow direction in the channel is smooth，the flow velocity is stable within 3 m/s，the navigation condition of the ship is good，the navigable water level of the left channel can be reduced from 5 m above the current design water level to 2 m.