Nandong Reservoir is located in the area of Ganlan Town, Dinghai District, Zhoushan City. Ganlan Town is surrounded by mountains on three sides. It is bordered by the sea in the west and Maqiu, the sea in the north, the dragon palace in the east, the white spring in the south, and the basin-like terrain in the middle. The Nandong Reservoir is located in Nandong Village, Ganlan Town, Dinghai District.