It is disadvantaged for the excavated-in harbor basins water exchange flux which has large water area but only one mouth, and the linked river is a way to exchange the water from basin to the outside.
港池水域面积较大的单口门挖入式港池不利于港池水体与外界的交换，连通河涌是解决港池水体交换方式之一。
2
Sediment deposition exists in the lake mouth of Changdou Harbor for a long time and develops seriously. It exerts great influences on the discharge and irrigation capacity of the river.