荆江三口洪道防洪治理措施探讨

荆江三口洪道目前存在逐年淤积、同流量水位抬高、分流能力逐年减弱的问题，对该地区防洪产生威胁，急待整治。探讨了在三口洪道部分河段采取控制支汊、强化主干并结合建设平原型水库的治理措施。 建立了宜昌至汉口河段，包括三口洪道和洞庭湖在内的一、二维嵌套数学模型，对治理措施的实施方式以及实施之后的防洪作用进行了分析。 结果表明，该措施可理顺水系、缩短防汛堤线、减轻防洪压力，还可以在枯水季节提供一定水资源，缓解该地区季节性缺水的问题。

Discussion on control measures for flood diversion channels of three outlets of Jingjiang River

There are problems in the flood diversion channels of three outlets of Jingjiang River,including deposition in long period,water level rise under the same discharge and gradual decrease in flood diversion,which threaten the flood control in the region and need to be harnessed.The harnessing measures are discussed,namely,controlling the branch channel in some of the flood diversion channels of Jingjiang River and strengthening the main channel,while combining with construction of plain reservoirs.The 1D and 2D coupled mathematical model for the reach form Yichang to Hankou,including the flood diversion channels of three outlets of Jingjiang River and Dongting Lake,is established.The implementation mode and the effect after implementation are analyzed.The results show that the measure implementation can straighten out the river system,shorten the flood control levee line and reduce flood control pressure.Furthermore,it can provide water resources in dry season so as to mitigate the seasonal water shortage in this area.