With the implementation of the Yangtze River 12.5 m deepwater channel first stage regulation project,the 12.5 m deepwater channel right boundary of Tongzhousha east waterway to Langshansha east waterway has become stable.But the left boundary of the deepwater channel,the Xinkaisha to Kuzigangsha branch is still in the natural evolution without regulation measures.We analyze the topographic changes since the project constructed.The results show that Xinkaishasand shoal is becoming narrow and long with the sand silted at the tail.The tail of Kuzigangsha sand shoal is moving southward and invaded into the deepwater channel.A new ditch between Xinkaisha and Kuzigangsha is in developing,and the 10 m fathom line linked up in December 2015.These changes will take the negative effects to the maintenance of deepwater channel,and it is suggested that the related research on the follow-up improvement project of deepwater channel should be carried out as soon as possible.