Author(s): Fong-Zuo Lee; Tetsuya Sumi; Jihn-Sung Lai; Yih-Chi Tan; Cheng-Chia Huang
Linked Author(s): Tetsuya Sumi
Keywords: Sedimentation; Desiltation strategy; Frequency analysis; Flushing efficiency
Abstract: The annual mean loss of reservoir storage due to sedimentation is already higher than the increase of capacity by construction of new reservoirs for water supply, irrigation and hydropower. Thus, the sustainable use of the reservoir is more important and the storage is not guaranteed in the long term. Therefore, for prolonging the reservoir life, the desiltation strategy of the reservoir is always an important issue for reservoir long term operation. By dredging or excavation, deposited sediment may be mechanically removed from reservoirs because of valuable material for construction and connivance implementing. But, based on the characteristics of reservoir to classify suitable desiltation strategies is more efficient to deal with sedimentation problem. This study depended on frequency analysis method and venting efficiency of excited facilities for total inflow sediment volume and bypass with sediment replenishment strategies to planned valuable desiltation methods in wushe reservoir in taiwan. The characteristic of adopted reservoir in taiwan which have reliable and completed data in its historical records has been identified by the parameters of the turnover rate of water (cap/mar=total capacity/mean annual runoff) and sediment (cap/mas=total capacity/mean annual inflow sediment). Based on the frequency analysis, estimation of sediment transport capacity equation, experimental results with 3d numerical model and historical data, the inflow and outflow boundary condition of sediment were presented. In addition, using 1d numerical model, the flushing efficiency of bypass of objective case had been simulated to suggestion, using and planning to implement in wushe reservoir. In addition, the valuable historical excavation volume was also considered to implement sediment replenishment. Therefore, the results of desiltation strategies in this study are reasonable to maintain reservoir capacity as possible as we can and make sure the reservoir functions can prolong working.