调汉江之汛水 冲黄河之泥沙

Flushinow River Sedimentg the Yell by Diverting Flood Water From the Han River

水少沙多是黄河下游灾害的根源。针对水少,将南水北调中线黄河以南总干渠引水流量扩大为1500m^3/s,在6月21日至9月30日的汛期100天中,从丹江口水库及唐白河调截汛水83亿m^3入黄河冲沙,每年可减少河道淤积1.0～1.5亿t,使下游河道的淤积得到一定的缓和。调汛水与淮、海平原供水区用水无争,对丹江口水库效益无大影响。遇黄河大洪水时,根据预报暂停调水,错开洪峰,不会给下游防洪添加威胁;遇中常洪水增加防汛负担和滩区淹没的机遇是暂时的、过渡性的。

The characteristic of less runoff with more sediment is the source of calamities in the lower YellowRiver.To counter the situation of less runoff,it plans to increase the diversion discharge of the general canalto the south of the Yellow River which is the middle route of water transfer project from south to north to1500m^3/s.During 100 days of flood season from June 21 to September 30,it plans to divert 8 billion m^3 offloodwater from the Danjiangkou Reservoir and the Tangbai River to the Yellow River for flushing the sedi-ment.By that way,100～150 million tons of sediment in the channel can be reduced annually and the prob-lem of sedimentation in the lower river can be solved to a certain degree.The floodwater diversion is no adispute with the water supply of the Huai Hai plain and no big influence to the benefits of the DanjiangkouReservoir.According to weather forecasting,if there is a big flood in the Yellow River,the diversion can bestopped for staggering the peak and the flood control of the lower reaches can not be threatened;if it is apermanent flood,the chances of increasing the burden of flood control and inundating floodplains are tempo-rary and transitional.