圖書典藏及影音數位平台

鑒於以往水利建造物檢查僅單點式針對構造物本身是否受損，預防因建造物損壞所造成的災害，無法全面性的檢視潛在危險，加以防範避免災害的發生。因此導入風險管理之觀念，猶如全流域健檢，藉由流域水系之風險評估，以了解高風險河段之致災原因，並考量環境可用資源，擬定可行的對策及計畫，依計畫分年分期執行，並隨時檢討執行的成果作為後續精進的參考，以達減低災害發生的目標。

In the past, the examination of hydraulic structure safety is mostly done from site perspective. However, such approach cannot comprehensively investigate potential risks within watershed scope. This project applies the concept of risk management to assess PuZi watershed for understanding the potential risk and corresponding causes . The available resources for risk prevention are also considered to formulate feasible policies and plans preventing disasters. The goal of this project is to develop risk maps in each sections in PuZi watershed, and find strategies and solutions for risk prevention, according to different risk level. The low elevation of middle and down reach of the watershed lead to poor drainage capacity, hence the high-and-low diversion is suggested to be developed. Consider Runoff Distribution region due to National Spatial Planning, the water storage space increases. Flooding area and elevation can be considered with flood insurance to decrease the disaster damage for densely populated settlements. Moreover, PuZi river’s middle reach is meandering, and its thalweg is stable and obvious. To prevent loss of riverbank, the levee surface and foundation structures ought to be protected near the concave banks or levee that flows directly attack on. Furthermore, levee impacted by flows in meandering sections need groin works to divert water to the center of channel and to establish channel bank through channel arrangement. Focus on flood prevention, improving the exist structures and regularly monitoring channel bed evolution are necessary. Dredging is also an important strategy. It helps channel maintenance. In addition, opening channel spaces except the vulnerable regions and densely populated villages increase flood capacity and space for trapped sediment and decrease flooding risk. The sloping and flood prevention structure in the upper reach should be properly improved because of highly flow velocity and massive sediment, which can be further controlled and conserved to decrease among in down reach. Finally, enforcing warning systems and emergency planning for those who are closed to the levee are also in need. The monitoring system for the bank safety and community-based approach for high potential risk villages can be established.