汉江杜家台分洪工程行洪道分流效果分析

Analysis of flood discharge effect of Dujiatai Flood Diversion Project on the Hanjiang River

杜家台分洪工程行洪道系与东荆河并列的原汉江天然分流故道,上接汉江进洪闸杜家台分洪闸,下通长江泄洪闸黄陵矶闸。2005年10月汉江大水,湖北省防指首次进行了行洪道分流尝试,直接分流汉江洪水约3.7亿m3到长江。2011年9月,汉江发生了秋季洪水,再次利用行洪道直接分流汉江洪水约2亿m3。两次开闸分流,蓄洪区都只有两处较小的蓄洪围垸漫溃,以最小代价换取了最大安全。建议完善杜家台分洪工程行洪道分流模式,使其成为安全的分流通道,实现适时适量灵活分洪运用的目标,满足汉江中小洪水的常规运用需要。

Dujiatai Flood Diversion Project refers to the old nature river course of Hanjiang that is parallel with the Dongjing River and connects with Dujiatai Gate at the upstream and Huanglingji Gate at the downstream.It has a possibility of flowing into the Yangtze River when extra floodwater is discharged from the downstream of the Hanjiang River.During the big flood in October 2005,370 million cubic meters of water was discharged from Hanjiang into the Yangtze according to the instruction of Flood Control Headquarters of Hubei Province.In September 2011 when Hanjiang experienced the biggest autumn flood since 1983,the project is employed to discharge 200 million cubic meters of floodwater.The opening of Dujiangtai Flood Diversion Gate in 2005 and 2011 only caused break of two small flood retention ponds and operated safely at minimum cost.It is suggested to improve the flood discharge model of the project and realize timely and flexible flood discharge so as to satisfy the needs of its normal operation in cases of small and medium floods of the Hanjiang River.