The Application of Decision Tree to the Optimal Operation Rules of Reservoir Flood Control and Sediment Sluicing– A case of Tseng Wen Reservoir

• Main Authors: Chang, Han-Wen, 張瀚文
• Other Authors: Chang, Liang-Cheng
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/7tcbdr

碩士 === 國立交通大學 === 土木工程系所 === 102 === Typhoon events are major sources of water in Taiwan. However, extreme storm events could cause floods and damages due to fragile geological conditions and mountainous area with steep slope of terrain. The storm events not only cause debris flow but also bring huge amount of sediment into reservoirs which would reduce the life of reservoirs. Therefore, how to operate a reservoir during storm events considering multiple objectives, flood control, water supply, and sediment sluicing, is a critical issue. This study develops an optimization planning model for reservoir operation during storm events considering flood control and sediment sluicing. In this optimization model, genetic algorithms, water and sediment simulation model, and reservoir operation rules are incorporated for realistic results. The result shows the optimal reservoir release hydrograph considering dam safety, operation rules, water supply, and sediment sluicing. In addition, decision tree is used to provide operation principals considering predefined scenarios which include various reservoir's initial storage, target storage, and synthesis storm events. Compare the optimization planning model (OPM) with the decision tree operation rules (DTOR), the DTOR model produces 1.4% more of the sediment removal but 6.40×106 m3 less of reservoir storage than the OM model output for the event of Krosa Typhoon in 2007. For the event of Jangmi Typhoon in 2008, the DTOR model produces 2.2% less of the sediment removal and 20.54×106 m3 less of reservoir storage than the OPM model output. Compare the DTOR model with the historical record, the DTOR model produces 15.4% more of the sediment removal but 8.38×106 m3 less of reservoir storage than the historical record of the Krosa Typhoon; and 24.4% more of the sediment removal but 7.58×106 m3 less of reservoir storage than the historical record of Jangmi Typhoon. The results show that the proposed DTOR model can increase the sediment sluicing and the life of the reservoir.