三峡水库运用20a后对草尾河航道的影响

Channel changes in Caowei Reach after 20 years operation of Three Gorges Reservoir

三峡水库运用后,从三口进入湖区的水沙将会在中枯水期发生一定的变化,对草尾河航道产生一定影响.利用三口分流以及城陵矶水位研究的最新成果,计算蓄水20 a后进入该河段水沙的变化,水库调蓄作用导致草尾河在10、11月份水位下降,河段比降、流速均增加,部分日期不能满足通航要求;12月至次年3月份枯水期水位略有增加,且低于设计水位的天数有一定减小,河段比降、流速减缓,因此通航条件将会有一定的改善;4月份水位下降,比降、流速略有增加,5、6月份水位增加,且河段比降、流速减缓,在该3个月期间均满足通航条件.

After the operation of the Three Gorges Reservoir, the flow and sediment characters about this river will change in the relatively low runoff periods, which will bring some impact on the channel in the Caowei Reach. Based on this, using the latest research achievements about the flow of the three diversions and Chenglingji water levels to calculate the changes in the flow and sediment characters about this river after the Three Gorges Reservoir being operation 20 years; the results show that, the more uniform discharge processes will lead to the water level dropping , slope and velocity increasing in October and November; sometime it can not meet the navigation requirements; from December to March next year, the water level has a slight increases, slope and velocity will slow; so the navigation requirements will have a certain improvement; the water level will drop, a slight increase in slope and velocity in April, but meeting the navigation requirements, the water level increase , a slow in slope and velocity in May and June, also meeting the navigation conditions.