Research on sediment problem solutions for the Three Gorges Project and it operational effects
The sediment problem is one of the key technical problems of the Three Gorges Project (TGP).Systematic and continuous studies on major engineering sediment problems have been carried out during various stages of the feasibility study,design,construction and operation of the TGP,and the corresponding solutions have been put forward.In this paper,the sediment problem solutions for the TGP are analyzed and summarized including:the operation mode of"storing clear and releasing muddy" to mitigate reservoir sedimentation and maintain long-term effective capacity;measures to control sediment problems in the port and navigation channel in the reservoir backwater area;the sediment control layout plan of the navigation approaching channel and the water diversion for the power station;the prediction of long-distance scour and the changes in river regime for the downstream channel of the dam;and the impacts of the TGP to the navigation channel and the countermeasures.It shows by analyzing the field measured reservoir sedimentation and downstream channel erosion since the TGP impoundment in 2003 that:the sediment has been mainly deposited in the dead storage,the loss of effective storage capacity is minor and the navigation conditions has been significantly improved;the river regime downstream of the TGP has been quite stable in general,with long-distance channel erosion and the erosion continue propagating downstream;and the navigation channel depth has been maintained after river management in the middle and lower reaches of the Yangtze River.The TGP sediment problem solutions have been preliminarily examined,and it shows that the sediment problems and their impacts have been within the predictions of the feasibility study and preliminary design.Due to the long-term and contingency of sediment problems,the hydrology and sediment monitoring should be continued for a considerable period of time,and the studies on reservoirs optimal operation,downstream channel erosion,management of river-lake relation,and the evolution of the Yangtze River estuary and other problems should be strengthened.
Three Gorges Projectstoring clear and releasing muddyreservoir sedimentationchannel erosionsediment problem in navigation channel
NETL
NSTL
万方数据
维普
