大潮州地下水補注湖防洪操作對沿海地區之淹水減災之效益評估

Evaluation of the Benefit of Flood Reduction by DaChaoZhou Groundwater Recharge Lake Operation in a Coastal Area

林家輝(Lin Jia-Hui)

指導教授 ： 陳金諾

國立屏東科技大學/國際學院/土壤與水工程國際碩士學位學程/碩士(2018年)

https://doi.org/10.6346/THE.NPUST.SWE.001.2018.E02

摘要

台灣在地表水供應不足或經濟成本考量下，部分地區民眾大量抽取地下水，造成地層下陷、海水入侵及土壤鹽化等問題，屏東縣政府於林邊溪上游設置大潮州地下水補注人工湖，引入林邊溪上游溪水補注地下水，洪水時期兼具分洪功能。
本研究以林邊溪上游所設置之大潮州地下水補注湖(DaChaoZhou groundwater recharge lake)為研究對象，並應用已建立之地文性淹排水模式(Physiographic Inundation-Drainage model)以各重現期距年(1.1年、2年、5年、10年、25、50年、100年及200年)之洪水事件進行模擬引水閘門不同開啟高度，配合湖區預留不同防洪蓄水容積之防洪操作，並分析各防洪操作下，對淹水深度、淹水面積、淹水體積、淹水延時之影響，並進一步分析林邊溪集水區下游各重現期距年防洪操作前後淹水風險減少百分比。由結果顯示，人工湖於各防洪操作下對於淹水深度、淹水體積及淹水風險有減少之效果，淹水風險減少最高可達8.18%。

關鍵字

防洪操作 ； 地文性淹排水模式 ； 人工湖 ； 淹水災害 ； 淹水風險

並列摘要

With insufficient surface water supply in Taiwan and consideration of economic costs, people in some area have been extracting a huge amount of groundwater thus causing various problems of land subsidence, seawater intrusion, and soil salinization. Pingtung County Government built the DaChaoZhou groundwater recharge lake in the upstream of Linbian River to introduce water from the upstream of Linbian River to recharge the groundwater, which can also provide flood diversion function.
The DaChaoZhou groundwater recharge lake in the upstream of Linbian River is the research object of this study, and the established Physiographic Inundation-Drainage model is utilized to simulate different opening heights of diversion gate based on flood events in each return periods (1.1-, 2-, 5-, 10-, 25 -, 50-, 100-, and 200- year) in coordination with the flood prevention operations based on different preserved flood storage capacities in the lake.
The impacts of various flood operations on inundation depth, inundation area, inundation volume, and inundation duration will also be analyzed. There will also be further analysis of percentage reduction of inundation risk before and after the flood prevention operation of each return periods in downstream of Linbian watershed. The results indicate that under various flood prevention operations, the artificial lake can lead to reduced inundation depth, inundation volume, and inundation risk, and the reduction of inundation risk can be as much as 8.18%.

並列關鍵字

flood prevention operation ； Physiographic Inundation-Drainage model ； artificial lake ； inundation disaster ； inundation risk

參考文獻

Alvaro, S. W., Luis, G., M. D. B. and Luis G. Catillo. 2013. Extreme flood abatement in large dams with gate-controlled spillways. Journal of Hydrology 498:113-123.

Chen, Y. W., Chu, H. J., Chang, L. C. and Fu, Y. C. 2009. Optimizing The Conjunctive Surface and Operations of a Multi-Lake System. Journal of the Chinese Institute of Civil and Hydraulic Engineering 21(3):295-305.

Chen C.N., Tsai C.H. & Tsai C.T. 2006. Simulation of sediment yield from watershed by physiographic soil erosion-deposition model. Journal of Hydrology 327(3-4):293-303.

Gong, C. H., Lu, Y. X. and Liao, Y. J. 2007. Case Study on Inundation Simulation Applied to Disaster Prevention. Sinotech Engineering 95:51-58.

Gain, A. K. and Hoque, M. M. 2013. Flood risk assessment and its application in the eastern part of Dhaka City, Bangladesh. 2013. Journal of Flood Risk Management 6(3):219-228.