淹水災害影響範圍劃設之研究

臺灣年平均雨量約2,500mm，平均每年約3~4個颱風侵襲臺灣，而臺灣地區以颱風災害造成的人員傷亡與災害損失為最多，颱風挾帶豪雨可能造成淹水災害，在臺灣淹水災害仍屬發生頻率較高且影響民眾生活最多的天然災害。本研究以高屏溪流域為例，應用地文性淹排水模式模擬演算，並依淹水深度、淹水時間配合土地利用及人口密度等淹水災害損失因子進行淹水災損度之分析，進一步應用淹水災損度及災損發生之次數計算淹水災害影響度。研究結果顯示，相近的累積雨量，降雨強度愈大、降雨延時愈短，則淹水面積愈大。嚴重淹水災損範圍大致分布於中汕里、西汕里、後村村、大洲里、前進里及檨腳村等河川下游沿岸村里。本研究成果可提供相關單位進行流域管理與洪氾災害防治及應變決策研擬之參考，提升政府未來對於洪氾災害之防救能力。

關鍵字

淹水災害；地文性淹排水模式；淹水災損度；淹水災害範圍劃設

並列摘要

Taiwan is characterized by having a mean precipitation of 2500 mm/year. Taiwan is hit by an average of 3 to 4 typhoons, occurring during summer-autumn season. During the typhoon period, a number of disasters of serious floods and even deaths have occurred and caused a lot loss in Taiwan. Flooding disasters occur frequently and have the greatest impact on people’s lives. Kaoping river basin is used as an illustrative example in this study. The Physiographic Drainage - Inundation model was applied and combined with a geographic information system (GIS), to simulate the potential inundation, inundated depth, inundated area, inundated volume, and inundation duration. Furthermore, the degree of flooding disaster loss and the disaster occurrences frequency were analyzed delineation for the ambit of flooding disasters. The results indicated that Under the similar accumulated rainfall, the greater the intensity and shorter the duration of rainfall resulted the larger the flooded area. The areas of severe flooding damages were distributed in the villages along the downstream such as Zhongshan village, Xishan village , Houcun Village, Dazhou village , Qianjinli and Mijiao Village. The research results from the study will provide a reference for the practicing units in flood disasters prevention and control, and watershed management. The database of delineation for the ambit of flooding disasters are established to improve the disaster prevention capacity of the flood disasters for government.