一、概况长江口徐六泾河段上起左岸南通市狼山,下至右岸常熟市徐六泾河口,全长约25公里,河道走向南偏东,平面形态呈藕节状,属暗沙型多分汊河道。主要沙洲有通洲沙、常阴沙、狼山沙、铁黄沙及近年在狼山沙头部左侧形成的新开沙。本河段目前的河势是:上游长江主流紧贴右岸老海坝微弯河岸下泄入通洲沙东水道,1982年8月水文测验实测东水道分流量为94%。通洲沙西水道分流量仅为6%。通洲沙东水道在营船港以下又被狼山沙分割为狼山沙东、西两股水道,其主支汊经历了一个调整过程后,目前狼山沙东水道为主汊,西水道为支汊。狼山沙东、西水道及通洲沙西水道三汊水流在徐六 I. Overview Xu River from the upper reaches of the Yangtze River estuary on the left bank of Nantong Langshan, down to the right Changshu City, Xu Liujing River estuary, a total length of about 25 km, the river goes to the east and south, the shape of a lotus root joints, Sub-divided 汊 river. The main sandbar Tong Chau, Chang Yin Sha, Langsha sand, iron yellow sand and sand in recent years, the head of the Shashan formed a new open sand. The current river in this reach is as follows: The mainstream of the upper reaches of the Yangtze River flows into the Tongzhou Shadong Waterway along the slightly curved river bank of the old dam on the right bank. In August 1982, the measured diversion of the East Waterway was 94% in the hydrological test. Tong Chau Shaxi channel diverted only 6%. Tung Chau Cha East waterway in the camp ship port following the Wolf Sands is divided into Langshan Sha East, West two shares of the watercourse, the main branch has undergone an adjustment process, the current Langsha Shadong waterway is mainly 汊 West Waterway For the branch. Langshan Sha East, Western Waterways and Tong Chau Shaxi waterway Sanliu water flow in Xu six