黄河第三次调水调沙试验

The Third Test of Water and Sediment Regulation Conducted on the Yellow River

黄河第三次调水调沙试验于2004年6月19日～7月13日进行。这次试验利用汛前的水库蓄水,并充分借助自然的力量,通过万家寨、三门峡、小浪底干流水库群的联合调度,辅以人工的泥沙扰动措施,在小浪底库区人工塑造了异重流,调整了其库尾段不利的淤积形态,加大了小浪底水库排沙量,减少了水库淤积;同时,利用进入下游河道水流富余的挟沙能力,在黄河下游"二级悬河"及主槽淤积最为严重的卡口河段实施了河床泥沙扰动,减轻了下游淤积并增强了下游河道的主槽过洪能力。试验取得了预期效果,小浪底库区淤积三角洲冲刷泥沙1.329亿m3,设计淤积平衡纵剖面以上淤积的0.385亿m3泥沙被全部冲走,小浪底库尾淤积形态得到了合理调整;下游卡口河段扰起泥沙164.13万m3,扰沙河段的平滩流量增加了510～640m3/s;下游河道利津以上各河段均发生冲刷,小浪底—利津共冲刷泥沙0.6422亿t。

The third test of water and sediment regulation of the Yellow River is conducted in the period from June 19 to July 13, 2004. The test has created artificial density current in the Xiaolangdi Reservoir area, regulated the sedimentation behavior which is unfavorable to the tail reach of the reservoir, increased sediment discharging capacity and decreased siltation of the reservoir through utilizing the reservoir storage before flood season, fully having the aid of natural power and reservoirs joint operation of Wanjiazhai, Sanmenxia and Xiaolangdi located on the main stream of the Yellow River and assisting with the measures of artificial sediment disturbance. At the same time, it has conducted sediment disturbance at 'the secondary suspended river' of the lower reaches and the natural channel-control section where sedimentation is the most serious, reducing sedimentation in the lower channel and increased the flood capability of the main channel in the lower river by utilizing the surplus capability of sediment carrying of the water flowing into the lower channel. It has achieved the expected effects as follows: 132.9 million m^3 sediment deposited in the Xiaolangdi Reservoir area has been washed out and all 38.5 million m^3 sediment deposited above longitudinal profile of designed sedimentation balance washed away, rationally regulating the sedimentation behavior of the tail reach of the reservoir; 1.641 3 million m^3 sediment at the natural channel-control section of the downstream disturbed and 510～640 m^3/s bankfull discharge at the disturbed section increased and; each section above Lijin on the lower reaches scoured and all together 64.22 million tons of sediment in Xiaolangdi-Lijin reach washed out.