仰山三级水电站取水口的防沙措施

仰山三级水电站采取低坝取水发电。由于河道受上游一级龙头水库建设的影响,破坏了河道天然水沙条件的平衡。为了防止大量泥沙进入三级站,淤塞发电隧洞进口,在上游河道(库尾)设置拦沙堰、发电隧洞进口设置“导沙坎—沉沙池—排沙涵管”、坝前设置排沙底孔的综合防沙措施。经过近6年的运用,摸索出了一套完整的运用方式,水库淤积控制在死库容范围内,且逐步趋于稳定。

Measurements Before the Inlets of Yangshan Third Cascade Hydro-power Station with Respect to Sediment Prevention

At Yangshan third-cascade hydro-power station, a low dam is adopted and electricity is generated by use of channelling water from the reservoir. Because the river course of the upper reach of the reservoir is affected by the upstream cascade hydropower stations, the original adaptation of its flow and sediment must be destroyed. In order to prevent sediment from moving into the turbines and keep the inlet from being silted up, a multiple measure composed of sediment retaining weirs at the end of the reservoir, sediment barriers and silting basin or drainage trench before the inlets of turbines is adopted. Through its application history of about 6 years, a complete utilizing way has been found out, and the level of sediment deposition in the reservoir has been controlled below the dead level and steady.