RECENT IMPROVEMENT OF GAO QIAO NEW CHANNEL ON HUANGPU RIVER

The Gao Qiao new channel is located at a crossing between two reversed curves of the Huangpu River. In the early 1950s, more than 400,000 m3 of sediment had to be dredged every year to maintain navigation. Desp ite recurrent dredging, the required navigable depth was difficult to maintain due to heavy siltation. Starting in 1955, studies were undert aken for improving the situation. Unfortunately, traditional rectifica tion work could not be effectively applied to that section of the rive r that actually had become part of the port area. Later, using experie nce gained from similar sections of the river where positive changes h ad taken place as a result of local normalization of shorelines, the c hannel was greatly improved with little investment. The right bank of the channel has been realigned by using the empirical relation between channel width and depth. Construction of a new bund of embankment has constricted the excess width of the straight portion of the crossover . The results were quite satisfactory. No dredging operations have bee n required to maintain a navigable depth in recent years.