随着黄河中上游水利工程的大量兴建,以及水土保持与灌溉的发展,洪水发生的机会与洪峰流量大幅度减小,不再需要下游宽河漫滩削峰。近年来对黄河窄深河槽泄洪输沙机理、河道输沙能力有了新认识,认为下游河道具有极强的泄洪和输沙能力,可为黄河下游河道的治理指明方向。三门峡水库改建后“蓄清排浑”运用的减淤作用已经使花园口以上河道基本不淤。小浪底水库投入运用13 a,下游河道均发生巨大变化,下游河道水位全程降低1.0~2.2 m,平滩流量迅速增大,但是游荡性河道依然宽浅散乱,急需进行双岸整治,形成窄深、稳定河槽；通过小浪底峡谷水库的泥沙多年调节,优化进入下游的水沙组合,并长期发挥作用。将小浪底水库泥沙调节到流量大于3000 m3/s时宣泄,利用改造后新河槽输沙入海,可以控制河槽不抬高,并大幅度增加水库兴利库容。%With the construction of large hydropower projects on the upper and middle reaches, the development of soil-water conservation and irrigation projects, the probability that a big flood event will occur and flood peak discharges have been greatly reduced. It is unnecessary to widen the lower-reach river to allow floodplain inundation for flood peaks reduction. In recent years, there is a major breakthrough in the understandings of the mechanism and capacity of the sediment transport in the narrow and deep channel of the Yellow River. Lower-reach channel has huge flood discharge and sediment transport capacity, which points out the future direction of harnessing the river. After the reconstruction of Sanmenxia Reservoir and the operational mode of “storing clear water and releasing muddy water” to reduce deposition, non-siltation has already been achieved for the channel upstream of Huayuankou. After the operation of Xiaolangdi Reservoir for 13 years, great changes have taken place in the lower-reach channel with maximum longitudinal water surface elevation reduction of 1.0-2.2 meters, and the bankfull discharge has been increased dramatically. But the wandering reaches are still wide, shallow, scatter and ill-conditioned, and they need to be regulated at both banks to form a stable, deep and narrow channel. Through multi-year sediment regulation of valley type of reservoirs like Xiaolangdi, the combinations of flow and sediment entering the lower-reach can be optimized, and the reservoir can be used for a long time. Sediment should be managed to be released when discharge is greater than 3000 m3/s, and it should be transported through the regulated new channel to sea. By using this approach, the river bed will not be elevated by deposition, and the beneficial use of the reservoir will be significantly increased too.
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