Xiazhi ferry wharf expansion project is located in the northwest of Xiazhi island.Two ferry berths of 1 000 GT with a floating structure are to be built.Using the data of environmental quality investigation of the coastal area near the engineering site,we analyze the impact on water quality,ecological environment and other sea use activities.The result indicates that the construction will have a slight influence on water quality and sea use activities,but will cause some losses of fishery resources.The artificial enhancement and release of fish is advised to reduce the damage to the ecological environment.In general,it is feasible to implement the sea use of the project.